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Sample records for angioplastia con stent

  1. ANGIOPLASTIA PERCUTÁNEA CON STENT EN EL TRONCO PRINCIPAL DE LA ARTERIA CORONARIA IZQUIERDA / Percutaneous angioplasty with stent in the left main coronary artery

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    Javier Almeida Gómez

    2012-10-01

    Full Text Available ResumenIntroducción y objetivos: La afectación significativa del tronco común izquierdo, es la más letal de las presentaciones de la enfermedad arterial coronaria. El tratamiento de elección, es la cirugía de derivación aorto-coronaria. En varios estudios multicéntricos, se sugiere la posibilidad de tratar la enfermedad de tronco mediante el intervencionismo coronario percutáneo con implantación de prótesis endoluminal o stent. El objetivo de esta investigación fue caracterizar la angioplastia percutánea con stent en el tronco principal de la arteria coronaria izquierda. Método: Se realizó un estudio observacional, descriptivo y transversal en 21 pacientes con angioplastia percutánea con stent en el tronco principal de la arteria coronaria izquierda, realizadas en el laboratorio de Hemodinámica y Cardiología Intervencionista del Hospital "Hermanos Ameijeiras", entre enero 2010 y julio 2011. Resultados: No existió diferencia significativa en el sexo. Predominó el grupo de edad entre 50-64 años (47,6 % y el color de la piel blanca (76,19 %. El factor de riesgo cardiovascular más encontrado fue la HTA (85,71 %, seguido de dislipidemia (47,61 %. El diagnóstico más observado fue la angina de esfuerzo estable, 14 casos (66,66 %. La lesión en el cuerpo del tronco (12 pacientes, 57,1 %, fue la más encontrada, seguida de la ostial (8 casos. El tipo de stent más utilizado fue el liberador de fármacos (61,9 %, y solamente 4 pacientes presentaban troncos protegidos quirúrgicamente. Conclusiones: La mayor cantidad de casos fueron electivos, con predominio de los troncos no protegidos. El factor de riesgo coronario más encontrado fue la HTA. Se encontró asociación significativa entre la diabetes mellitus y la localización ostial de la lesión tratada. / AbstractIntroduction and Objectives: Significant impairment of the left main coronary artery is the most lethal presentation of coronary artery disease. The treatment of choice

  2. Angioplastia con stent vs. cirugía de revascularización coronaria en enfermedad multivaso (ACIRE Coronary angioplasty with stenting vs. coronary bypass revascularization surgery in multivessel disease

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    Andrés Fernández

    2009-04-01

    Full Text Available La enfermedad coronaria de múltiples vasos, es causa frecuente de procedimientos de revascularización percutánea o quirúrgica. La evolución de los pacientes sometidos a cualquier tipo de intervención, ha sido objeto de variados estudios clínicos aleatorizados y sus resultados han sido diversos a favor de uno u otro procedimiento. En este estudio prospectivo de cohorte, se analiza el desenlace clínico de 400 pacientes con enfermedad coronaria de dos o más vasos y se comparan resultados entre cirugía de revascularización y angioplastia con stent. Las poblaciones fueron comparables en sus características basales. Resultados: la tasa de mortalidad hospitalaria, al mes, seis y doce meses es similar en ambos procedimientos de revascularización. Sin embargo, la morbilidad intra-hospitalaria es mayor en el grupo de bypass con una tasa de infarto inmediato post-procedimiento mayor en dicho grupo cuando se compara con el percutáneo: 4,5% vs. 0% (p=0,005, una tasa de infecciones superior: 15,8% vs. 1,6% (p=0,001 y una estancia hospitalaria en unidad de cuidado intensivo más prolongada: 21,8% vs. 1,1% (p=0,001. La tasa de MACE (muerte, infarto, necesidad de revascularización del vaso previamente tratado intra-hospitalaria asociada a la cirugía de revascularización, es significativamente mayor que la encontrada en el grupo de estrategia percutánea 8,4% vs. 1,6% (p=0,002 a expensas de una mayor tasa de infartos en el grupo quirúrgico. Los MACE a un mes y seis meses son similares en ambos grupos (tasa de 8,9% y 10,4% respectivamente para el grupo quirúrgico y del 5,7% y 15,5% para el grupo percutáneo (p=NS. A 12 meses la tasa de MACE fue menor en el grupo quirúrgico (11,9% cuando se comparó con el grupo percutáneo (19,2% (p=0,045. Dicha diferencia se explica por una mayor necesidad de procedimientos de revascularización por falla del vaso tratado en el grupo de intervencionismo coronario percutáneo. Conclusiones: en la poblaci

  3. Análise morfométrica da carótida de suínos submetidos a angioplastia com ou sem implante de stent de cromo-cobalto Morphometric analysis of swine carotid artery angioplasty with or without cobalt-chromium stent implantation

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    João Luiz de Lara Elesbão

    2010-06-01

    Full Text Available Contexto: A hiperplasia intimal é a reação tardia mais comum decorrente da angioplastia. O uso de stents de cromo-cobalto é bem estudado na circulação coronariana, porém não há muitos estudos que abordem o uso desses stents nas circulações carotídea e periférica. Objetivo: Analisar mediante morfometria a reação intimal presente na artéria carótida de suínos submetidos a angioplastia isoladamente e a angioplastia seguida de implante de stent de cromo-cobalto. Materiais e métodos: Em oito suínos, foi realizada angioplastia da artéria carótida comum direita e angioplastia seguida de implante de um stent de cromo-cobalto na artéria carótida comum esquerda. Após 4 semanas, os animais foram submetidos a eutanásia para a retirada de amostras de tecido arterial e preparo de lâminas histológicas. As imagens das lâminas foram digitalizadas e analisadas por programa de morfometria digital. A análise estatística foi realizada através da média e desvio padrão das áreas em cada grupo, utilizando-se o Teste t de Student. O valor de p Background: Intimal hyperplasia is the most common delayed response to angioplasty. The use of cobalt-chromium stents is well studied in the coronary circulation; however, there are few studies on their use in the carotid and peripheral circulation. Objective: To analyze the intimal reaction in a swine carotid artery undergoing simple angioplasty and angioplasty followed by implantation of cobalt-chromium stent. Materials and methods: We carried out angioplasty in the right common carotid artery and angioplasty with cobalt-chromium stent in the left common carotid artery in eight swine. Four weeks later, all animals were sacrificed for arterial tissue sampling and preparation of histological slides. Slide images were scanned and analyzed using a digital morphometry program. Statistical analysis was performed by mean values and standard deviations of the areas in each group, using the Student's t

  4. Morphometric analysis of the intimal reaction after stent implantation in iliac arteries submitted to angioplasty in pigs Análise morfométrica da reação intimal secundária ao implante de stent em artérias ilíacas submetidas à angioplastia em suínos

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    Cyro Castro Júnior

    2006-06-01

    Full Text Available PURPOSE: To compare through digital morphometry, the intimal thickening of the common ilíac arteries (CIA in pigs, submitted to angioplasty and angioplasty followed by stent implantation. METHODS: Angioplasty was performed in 10 pigs in both CIA, followed by a stent implantation in the left CIA. After four weeks, the aorto-iliac segment was dissected. Histologic slices where divided in three groups: left CIA in the area of the proximal (group 1 and distal (group 2 implantation site of the stent and the region of angioplasty in the right CIA (group 3. The histological slices were digitalized to be analyzed by morphometry with calculation of the luminal, intimal and media layers areas. Descriptive statistics analysis was performed through average and standard deviation of areas on each group, using ANOVA, with LSD Post-Hoc test (pOBJETIVO: Analisar, por meio da morfometria digital, o espessamento intimal das artérias ilíacas comuns (AIC de suínos, submetidas à angioplastia e à angioplastia seguida do implante de stent. MÉTODOS: Em dez suínos, foi realizada a angioplastia da AIC bilateral, seguida do implante do stent na AIC esquerda. Após quatro semanas, o segmento aorto-ilíaco foi retirado. As lâminas histológicas foram divididas em três grupos: segmento proximal (grupo 1 e distal (grupo 2 do local de implante do stent na AIC esquerda e a área da angioplastia da AIC direita (grupo 3. As imagens das lâminas foram digitalizadas e analisadas por programa de morfometria com cálculo das áreas luminal, da camada íntima e da camada média dos cortes histológicos. A análise estatística foi realizada através de média e desvio padrão das áreas em cada grupo, utilizando ANOVA, com teste Post-Hoc LSD (p<0,05. RESULTADOS: Na análise das médias das áreas obtidas, foi encontrada diferença estatisticamente significativa quanto à camada íntima dos grupos 1 e 2, quando comparados ao grupo 3 e em relação à camada média dos grupos

  5. Aterectomía rotacional para manejo de expansión inadecuada de stent (stentablacion

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    Juan M. Sénior

    2017-11-01

    Full Text Available Resumen: El uso de la aterectomía rotacional para la ablación de parte de un stent metálico ha sido muy limitado. Se reporta el caso de una paciente de 40 años de edad, con inadecuada expansión del stent a pesar de la dilatación con balón de alta presión, debido a una placa severamente calcificada. La paciente es tratada con éxito con ablación del stent. Abstract: The use of rotational atherectomy for the ablation of part of a metallic stent has been very limited. We report the case of a 40 year-old female patient with an inadequate expansion of the stent despite the dilation with a high-pressure balloon, due to severely calcified plaque. Patient is successfully treated with stent ablation. Palabras clave: Stent, Ablación, Angioplastia coronaria, Keywords: Stent, Ablation, Coronary angioplasty

  6. Angioplastia del tronco de la arteria coronaria izquierda no protegido en pacientes con alto riesgo quirúrgico

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    Victor Mauro

    2008-01-01

    Full Text Available IntroducciónEl tratamiento de elección de la enfermedad del tronco de la coronaria izquierda (TCI es la cirugía de revascularización miocárdica (CRM. Un número creciente de pacientes presenta comorbilidades y/o inestabilidad clínica que condicionan un alto riesgo quirúrgico.ObjetivosEvaluar los resultados de la angioplastia (ATC del TCI no protegido en pacientes con alto riesgo para CRM (EUROSCORE = 6.Material y métodosDe 59 pacientes con ATC de TCI no protegido se excluyeron 8 con infarto agudo de miocardio (IAM en shock cardiogénico y 12 sin características de alto riesgo; de los restantes pacientes de alto riesgo fueron objeto de este estudio los 32 tratados con stents convencionales.Se comparó la mortalidad hospitalaria predicha por EUROSCORE logístico con la observada, así como la incidencia de complicaciones mayores y su evolución alejada.ResultadosLa mediana de edad fue de 76,5 años, el 41% tenía 80 años o más, el 22% eran mujeres, el 28% diabéticos, el 56% tenía disfunción ventricular moderada a grave, el 31% insuficiencia renal crónica, el 50% vasculopatía periférica, el 53% angina refractaria, el 22% IAM reciente, el 28% procedimientos de emergencia y la mediana de EUROSCORE fue de 10,5 puntos.El 41% de los pacientes presentaban compromiso del TCI distal. El éxito angiográfico fue del 94%. Se utilizaron inhibidores IIb/IIIa en el 47%, cutting balloon en el 28%, Rotablator® en el 3% y balón de contrapulsación en el 31%. En todos se implantó un stent y en el 50% se trataron otras obstrucciones.La mortalidad hospitalaria fue del 3,1% (intervalo de confianza del 95% 0,2%-14,5%, p = 0,003, en tanto que la predicha era del 23,8%. Ningún paciente presentó déficit neurológico, IAM transmural ni requirió diálisis. Un paciente debió ser sometido a CRM electiva por fracaso del procedimiento.La mediana de seguimiento fue de 15,5 meses, período en el que se registraron 6 muertes (2 cardiovasculares y 4

  7. Angioplastia coronaria en centros con residencia de cardiología en la Argentina. Estudio CONAREC XIV - Área de Investigación de la SAC

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    Bruno Linetzky

    2007-01-01

    Full Text Available IntroducciónLos nuevos tratamientos médicos y los avances técnicos, junto con la mayor experiencia adquirida en cardiología intervencionista, hicieron necesaria la realización de este nuevo registro, el protocolo CONAREC XIV, sobre empleo de angioplastia coronaria (ATC, un procedimiento que es seguro y eficaz para el tratamiento de la enfermedad coronaria.ObjetivoEvaluar las características de los pacientes, las indicaciones y los resultados de la ATC en nuestro país.Material y métodosSe realizó un registro prospectivo y consecutivo durante 6 meses de pacientes tratados con ATC en centros con residencia de cardiología. Se determinaron antecedentes, cuadro clínico de ingreso, tratamiento, resultados y complicaciones intrahospitalarias.ResultadosSe registraron 1.500 pacientes. La edad promedio fue de 62,8 ± 10,8 años y el 78,3% eran hombres. Antecedentes: 72% hipertensión arterial, 56,6% dislipidemia, 19,2% diabetes y 22,4% tabaquismo. Los cuadros clínicos de presentación fueron: 20% asintomáticos, 16,2% angina crónica estable, 45% síndrome coronario agudo sin supradesnivel del ST (SCA-SST, 19% síndrome coronario agudo con supradesnivel del ST (IAM-ST. En el 74,7% de los casos se realizó ATC de un vaso. Se utilizaron stents en el 94,5% de los casos y en el 18,7%, stents liberadores de drogas. El uso de pruebas funcionales previas a la ATC en cuadros estables fue del 53,9%, mientras que en el SCA-SST fue del 31,6%. La mediana de tiempo de evolución hasta la ATC en el SCA-SST fue de 1 día con un rango intercuartil 25-75% (RIC de 0 a 3. En el IAM-ST, el tiempo puerta-balón fue de 60 minutos (RIC 40-105 y la mortalidad fue del 8%.ConclusionesLa ATC se utiliza principalmente para el tratamiento de síndromes coronarios agudos. Se evidenció una tasa alta de uso de stents y de stents liberadores de drogas. El empleo de pruebas funcionales fue bajo. La tasa de complicaciones fue similar a la de los registros internacionales.

  8. Monitorización ultrasonográfica de endarterectomía carotídea y angioplastia transluminal percutánea como procedimientos de revascularización carotídea en estenosis de alto grado de la arteria carótida interna extracraneal

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    Benavente Fernández, Lorena

    2014-01-01

    INTRODUCCIÓN El ictus aterotrombótico por ateromatosis carotídea, es el responsable del 15-20% de todos los ictus. Siendo la arteria carótida interna (ACI) un vaso principal para la irrigación del parénquima cerebral, cuando dicha ateromatosis condiciona una estenosis significativa con alto riesgo tromboembólico se plantea la necesidad de un tratamiento revascularizador. La endarterectomía carotídea (EAC) y la angioplastia endoluminal (ASC) con o sin implante de stent son las dos opciones ...

  9. Estudio comparativo en pacientes con implante de stent liberador de droga y stent convencional. Resultados clínicos e indicaciones

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    Mariano Albertal

    2006-01-01

    Full Text Available Antecedentes Estudios aleatorizados demostraron la superioridad del uso de stents liberadores de droga (SL sobre el stent convencional (SC. La información en nuestro medio sobre el implante de SL es escasa. Objetivo Comparar los resultados clínicos obtenidos en pacientes sometidos a implante de SL versus SC en un centro terciario de la Argentina. Material y métodos Se incluyeron todos los pacientes sometidos a angioplastia electiva desde abril de 2003 hasta junio de 2005 y se dividieron en dos grupos: los pacientes sometidos a implante de uno o más SL (grupo SL, n = 373 y los sometidos solamente a implante de SC (grupo SC, n = 857. Resultados Las características basales fueron similares entre los dos grupos. En el grupo SL se observó un porcentaje mayor de lesiones en la arteria descendente anterior (50,6 versus 40,6%; p 0,001, gracias a una reducción de la tasa de cirugía coronaria (1,4% versus 5,8%; p = 0,045. Conclusión El uso de SL en un centro terciario de la Argentina demostró que es seguro y, en comparación con el implante de sólo SC, dio por resultado una tasa menor de reintervención, primariamente por haber reducido la tasa de cirugía de revascularización miocárdica

  10. Demoras en la realización de la angioplastia primaria en los pacientes trasladados con infarto agudo de miocardio: un problema médico-asistencial

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    Rodrigo Blanco

    2009-01-01

    Full Text Available IntroducciónEn el infarto agudo de miocardio (IAM está comprobado que cuanto más tempranamente se realice la reperfusión, mejores serán sus resultados a corto y a largo plazos, por lo que el tiempo entre el inicio de los síntomas y la reperfusión coronaria es un elemento de gran importancia en la estrategia de su tratamiento. Este lapso se encuentra conformado por dos períodos: “tiempo paciente” y “tiempo médico-asistencial”. En la angioplastia primaria, el análisis de estos tiempos y sus intervalos es el paso obligado para lograr una reducción de la demora a la reperfusión.ObjetivosAnalizar los tiempos en cada etapa del proceso traslado-realización de una angioplastia, ya sea primaria o de rescate, en pacientes con infarto agudo de miocardio con elevación del segmento ST (IAMEST que debieron ser trasladados desde un hospital derivador a un centro de referencia en el ámbito de la ciudad de Buenos Aires para someterse al procedimiento, como primer paso para un programa de optimización de los tiempos.Material y métodosEstudio prospectivo, observacional, de pacientes derivados al Hospital General de Agudos “Dr. Cosme Argerich” con diagnóstico de IAMEST e indicación de ATC. Se analizaron los tiempos parciales desde el inicio de los síntomas hasta la reperfusión coronaria, para lo cual se consideró “tiempo paciente” desde el inicio de los síntomas hasta la llegada al hospital derivador y “tiempo médico-asistencial” al comprendido entre la llegada al hospital derivador y la insuflación del balón.ResultadosSe incluyeron 313 pacientes, 225 (72% con angioplastia primaria (ATCP y 88 (28% con angioplastia de rescate (ATCR. Las medianas (cuartiles de tiempo en ATCP fueron: tiempo paciente: 90’ (40-240, llegada al hospital derivador-llamada al Equipo de Hemodinamia Cardiovascular de Urgencia (EHCU: 80’ (35-150, llamada EHCU-ingreso hemodinamia: 75’ (55-100, ingreso hemodinamia-balón: 35’ (23-52, tiempo m

  11. Alterações de difusão e perfusão cerebral por RM em angioplastia carotídea com \\"stent\\" sob proteção cerebral por filtros

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    Antenor Tavares de Sá Júnior

    2009-01-01

    INTRODUÇÃO: A angioplastia carotídea com stent (ACS) sob proteção cerebral é opção terapêutica em pacientes com estenose carotídea. Existe o risco de embolia apesar da utilização do filtro e as modificações na perfusão cerebral após tratamento da estenose carotídea não são claras. O propósito deste estudo é avaliar, após ACS sob proteção cerebral por filtros, modificações nas seqüências de RM de difusão (DWI) e perfusão (PWI), correlacionando-as com os aspectos técnicos da ACS, com as caracte...

  12. Evaluación económica del stent medicado vs. convencional para pacientes con infarto agudo de miocardio con elevación del ST en Colombia

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    Mateo Ceballos

    2014-11-01

    Conclusiones: El stent medicado con sirolimus no es costo-efectivo para pacientes con infarto agudo de miocardio con elevación del ST en Colombia. Se recomienda mayor investigación futura sobre la probabilidad de muerte y trombosis muy tardía del stent, así como en subgrupos específicos de pacientes y stents medicados de segunda generación.

  13. Controversias en el manejo actual de la coartación de la aorta

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    Edgardo Vanegas

    2013-09-01

    Full Text Available La coartación de la aorta fue descrita clásicamente como una simple estrechez del istmo aórtico que podría ser "curada" por medio de cirugía. En la actualidad se sabe que es la manifestación clínica de una vasculopatía arterial más amplia, en donde la afección del arco aórtico puede ser variable. La corrección quirúrgica ha demostrado ser un tratamiento efectivo para el manejo de la coartación aórtica nativa y permanece como el de elección en neonatos. De otra parte, la angioplastia con balón es el tratamiento de elección en niños con recoartación, cuyos resultados en la reducción aguda del gradiente aórtico posterior al manejo de la coartación nativa, son similares a los obtenidos con cirugía. La implantación de prótesis endovasculares (stents ha mostrado excelentes resultados a corto plazo tanto en niños mayores como en adultos con coartación nativa. En pacientes con coartación recurrente considerados de alto riesgo quirúrgico, la angioplastia con balón y la implantación de stent ofrecen una estrategia de manejo menos invasiva e igual de efectiva. Se prefiere el uso de stents sobre la angioplastia con balón en adultos y niños mayores con coartación recurrente, ya que el riesgo de recoartación y formación de aneurismas parece ser menor. No se cuenta con suficiente información acerca de los desenlaces a largo plazo posteriores al tratamiento percutáneo de la coartación aórtica. Este artículo revisa las controversias existentes en cuanto al manejo actual de esta condición.

  14. Controversias en el manejo actual de la coartación de la aorta

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    Edgardo Vanegas, MD

    2013-09-01

    Full Text Available La coartación de la aorta fue descrita clásicamente como una simple estrechez del istmo aórtico que podría ser “curada” por medio de cirugía. En la actualidad se sabe que es la manifestación clínica de una vasculopatía arterial más amplia, en donde la afección del arco aórtico puede ser variable. La corrección quirúrgica ha demostrado ser un tratamiento efectivo para el manejo de la coartación aórtica nativa y permanece como el de elección en neonatos. De otra parte, la angioplastia con balón es el tratamiento de elección en niños con recoartación, cuyos resultados en la reducción aguda del gradiente aórtico posterior al manejo de la coartación nativa, son similares a los obtenidos con cirugía. La implantación de prótesis endovasculares (stents ha mostrado excelentes resultados a corto plazo tanto en niños mayores como en adultos con coartación nativa. En pacientes con coartación recurrente considerados de alto riesgo quirúrgico, la angioplastia con balón y la implantación de stent ofrecen una estrategia de manejo menos invasiva e igual de efectiva. Se prefiere el uso de stents sobre la angioplastia con balón en adultos y niños mayores con coartación recurrente, ya que el riesgo de recoartación y formación de aneurismas parece ser menor. No se cuenta con suficiente información acerca de los desenlaces a largo plazo posteriores al tratamiento percutáneo de la coartación aórtica. Este artículo revisa las controversias existentes en cuanto al manejo actual de esta condición.

  15. Angioplastia coronaria en la República Argentina. Comparación de los resultados en la fase hospitalaria de los estudios CONAREC V y CONAREC XIV

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    Sergio Baratta

    2007-01-01

    Full Text Available La angioplastia coronaria (ATC es una técnica para el tratamiento de la enfermedad coronaria que se encuentra en constante evolución. El registro CONAREC V relevó características de pacientes sometidos a angioplastia durante el año 1996. Diez años después publicamos los resultados del estudio CONAREC XIV. ObjetivoComparar las características demográficas y clínicas, la utilización de dispositivos y de pruebas funcionales, los resultados y las complicaciones de la ATC en el estudio CONAREC V con el estudio CONAREC XIV. Material y métodosSe unificaron las bases de datos de ambos protocolos. Se compararon las variables continuas por medio de la prueba de la t y las categóricas con la prueba de chi cuadrado. Se construyó un modelo de regresión logística para determinar si disminuyó la tasa de complicaciones en el año 2005, ajustando por confundidores.ResultadosLos pacientes del CONAREC XIV fueron más añosos (62,8 ± 10,8 versus 60,6 ± 10,9 años, con mayor prevalencia de hipertensión arterial (72,4% versus 61,3%; p < 0,001 y diabetes (19,2% versus 16,9%; p = 0,017 y menor de tabaquismo (22% versus 38%; p < 0,001; presentaron enfermedad de tres vasos (20,2% versus 14,8%; p < 0,001 y ATC de más de un vaso con mayor frecuencia (25,3% versus 11,8%; p < 0,001; se incrementaron el uso de stents (94,5% versus 48%; p < 0,001 y la indicación por cuadros estables (36,3% versus 18,2%; p < 0,001. El uso de pruebas funcionales en este contexto fue menor en el año 2005 (54% versus 65%; p < 0,001.En pacientes con infarto agudo de miocardio, en el CONAREC XIV se observó una prevalencia menor de infarto anterior (46% versus 57,8%; p < 0,005 y de shock cardiogénico (7,3% versus 13,5%; p = 0,017. La tasa de complicaciones mayores fue menor en el último protocolo, CONAREC XIV (3,1% versus 8,9%; p < 0,001. En el modelo multivariado, pertenecer al último estudio disminuyó el riesgo de padecer eventos (OR 0,41, IC 95% 0,26-0,64; p < 0

  16. Current status of infrapopliteal artery stenting in patients with critical limb ischemia Estado atual do uso de stents na artéria infrapolítea em pacientes com isquemia crítica do membro

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    Marc Bosiers

    2008-09-01

    Full Text Available Due to the fear that early thrombosis and late luminal loss resulting from intimal hyperplasia might impede sustained patency of small-caliber arteries, such as those of the infrapopliteal bed, stent implantation in below-knee vessels remains controversial and is generally reserved for cases with a suboptimal outcome after percutaneous transluminal angioplasty (i.e. > 50% residual stenosis, flow-limiting dissection. Although evidence starts to build, favoring the use of stenting in the tibial area, results of well-conducted randomized controlled trials have to be awaited to change this strategy. Because of diameter similarities with coronary arteries, the first stents applied in the infrapopliteal vessels were all coronary devices. Once the feasibility of the stenting approach with these coronary products was shown, device manufacturers started to develop a dedicated infrapopliteal product range. To date, a broad spectrum of stent types has been used and investigated for the given indication. This article overviews the available literature and results of different balloon-expandable (bare metal, passive coated, drug eluting, self-expanding and absorbable stent types available for below-the-knee application and gives recommendations for future device technology advancements.Devido ao receio de que a trombose precoce ou a estenose tardia por hiperplasia intimal possam impedir a manutenção da perviedade em vasos de pequeno calibre, o uso de stents pós-angioplastia no leito arterial infrapoplíteo permanece controverso e geralmente é reservado aos casos de resultado subótimo após angioplastia transluminal percutânea (isto é, estenose residual > 50% ou dissecção com limitação do fluxo. Apesar de evidências começarem a favorecer o uso de stents no segmento tibial, é necessário aguardar o resultado de ensaios controlados, randomizados e bem conduzidos para mudar esta estratégia. Sendo estes vasos infrapoplíteos de diâmetro similar

  17. Angioplastia primaria optimizada: comparación de tres estrategias de administración de ABCIXIMAB intracoronario y sus efectos sobre el tamaño del infarto valorado mediante resonancia magnética cardíaca

    OpenAIRE

    Santos González, Belén

    2016-01-01

    Se ha demostrado ampliamente que el intervencionismo coronario percutáneo (ICP), cuando está disponible de forma inmediata, es el tratamiento de elección del Síndrome Coronario Agudo con elevación del segmento ST (SCACEST). Existe suficiente evidencia para afirmar que la angioplastia primaria es superior a la trombolisis intravenosa consiguiendo un mayor grado de permeabilidad de la arteria, reduciendo el riesgo de reoclusión y de reinfarto. Todos estos efectos se traducen en mejora de la sup...

  18. Angioplastia del seno coronario en el implante de electrodo del ventrículo izquierdo Angioplasty of coronary sinus in left ventricle electrode implant

    Directory of Open Access Journals (Sweden)

    Alejandro Orjuela

    2011-07-01

    Full Text Available Con el incremento de implantes de dispositivos de estimulación cardíaca en pacientes con miocardiopatía dilatada, el diseno día a día más sofisticado de los mismos para satisfacer los requerimientos de los pacientes con cambios anatómicos que surgen como consecuencia de la misma dilatación cardíaca, tales como modificaciones en el calibre, curso, longitud y número de venas coronarias, cada vez se encuentran mayores dificultades para lograr los objetivos anatómicos, en particular el sitio ideal de posicionamiento del electrodo de estimulación ventricular izquierda en el seno coronario. Esta situación limita, en algunos casos, el beneficio terapéutico de esta técnica, viéndose, en ocasiones, en la necesidad de someter al paciente a toracotomía para posicionar el electrodo en el epicardio posterolateral del ventrículo izquierdo. Es así como, con el objetivo de abreviar los tiempos y la morbimortalidad e incrementar el éxito del implante, se disenó una estrategia basada en la técnica de hemodinámica para vencer las obstrucciones de las arterias coronarias y lograr, mediante angioplastia de las estrecheces del seno coronario, un abordaje más preciso a un determinado vaso epicárdico preseleccionado. Se describe la técnica usada en la angioplastia del seno coronario para este propósito.The design of devices of cardiac stimulation in patients with dilated cardiomyopathy has become more sophisticated due to the increment of its implantation, devices that must satisfy the requirements for patients with anatomical changes that appear as a consequence of the cardiac dilation such as caliber modifications, course, length and number of coronary veins. Every time is more difficult to achieve the anatomical objectives, particularly the ideal place for the left ventricular stimulation electrode position in the coronary sinus. This situation limits in some cases the therapeutical benefit of this technique, occasionally facing to the

  19. Estudo prospectivo comparativo entre a endarterectomia e a angioplastia com stent e proteção cerebral no tratamento das lesões ateroscleróticas carotídeas: resultados em 30 dias Prospective and comparative study between endarterectomy and stent angioplasty with cerebral protection in carotid atherosclerotic lesions: 30-day results

    Directory of Open Access Journals (Sweden)

    Eugênio Carlos de Almeida Tinoco

    2006-12-01

    Full Text Available OBJETIVO: Analisar comparativamente os resultados, em 30 dias, entre a endarterectomia e a angioplastia com stent auto-expansível e filtro de proteção cerebral, avaliando a incidência de acidente vascular cerebral e óbito, bem como o tempo de permanência hospitalar no tratamento das lesões ateroscleróticas da bifurcação carotídea. MÉTODO: Estudo prospectivo, em que foram tratados 80 pacientes, sintomáticos e assintomáticos, com lesões estenóticas maiores que 60 e 70%, respectivamente, da bifurcação carotídea. Os pacientes foram divididos em dois grupos de 40 pacientes, que foram avaliados quanto a sexo, idade, comorbidades associadas e tabagismo. RESULTADOS: A taxa de acidente vascular cerebral e óbito foi de 5,0% em ambas as técnicas. Ocorreu um caso (2,5% de ataque isquêmico transitório no grupo endovascular e nenhum na endarterectomia. No que se refere ao tempo de internação, o tratamento endovascular apresentou menor tempo em relação à endarterectomia, sendo estatisticamente significativo (P OBJECTIVE: To comparatively analyze the 30-day results between endarterectomy and angioplasty using self-expandable stent and filter protection in the treatment of carotid bifurcation atherosclerotic lesions. The primary endpoint was to analyze stroke and death rate, as well hospitalization time. METHODS: Comparative and prospective study in 80 symptomatic and asymptomatic patients, with carotid bifurcation stenotic lesions greater than 60 and 70%, respectively. The patients were divided into two groups of 40 and assessed according to gender, age, associated comorbid conditions and smoking. RESULTS: The stroke and death rate was 5.0% for both techniques. There was only one case of transient ischemic attack (2.5% in the endovascular group. Regarding hospitalization time, it was significantly lower in favor of the endovascular technique, with statistical significance (P < 0.002. CONCLUSIONS: This study demonstrated a 5

  20. Quantificação volumétrica da hiperplasia neointimal em artérias ilíacas após implante de suporte intravascular metálico Volumetric assessment of neointimal hyperplasia in iliac arteries after metal stent implantation

    Directory of Open Access Journals (Sweden)

    Samuel Martins Moreira

    2009-08-01

    Full Text Available OBJETIVO: Quantificar a hiperplasia neointimal em artérias ilíacas após stent, correlacionando fatores clínicos, arteriais e materiais dos stents. MATERIAIS E MÉTODOS: De junho de 2003 a agosto de 2005, 60 pacientes realizaram angioplastia transluminal percutânea e stent. Desses, 30 foram reestudados com ultrassonografia intravascular. Os dados foram analisados no laboratório de análise quantitativa. RESULTA-DOS: Dezesseis pacientes eram do sexo masculino (53,3% e 14 (46,7%, do sexo feminino. A média de idade foi de 60,3 anos. Apresentaram hipertensão arterial 22 pacientes (73,3%, tabagismo, 18 (62,1%, hiperlipidemia, 20 (66,7%, e diabetes, 9 (30%. Foram implantados 20 stents de nitinol (66,7% e 10 de aço inoxidável (33,3%. Quatro pacientes eram TASC A (13,3%, 15 eram TASC B (50% e 11, TASC C (36,7%. O volume da hiperplasia variou de 49,02 mm³ a 112,87 mm³ (média de 80,33 mm³. O percentual de obstrução intra-stent variou de 18% a 47% (média de 27,4%. Os resultados clínicos obtidos com stent se mantiveram até o reestudo. CONCLUSÃO: A hiperplasia neointimal sempre ocorre após a angioplastia transluminal percutânea e stent, porém os percentuais de obstrução não foram superiores a 50% em nenhum caso. Não houve diferença estatisticamente significante dos percentuais de obstrução intra-stent quanto aos materiais dos stents, aos fatores clínicos e aos fatores arteriais.OBJECTIVE: To quantify neointimal hyperplasia in iliac arteries after stent implantation, correlating clinical, arterial factors and stent material. MATERIALS AND METHODS: In the period from June/2003 to August/ 2005, 60 patients were submitted to percutaneous transluminal angioplasty and stenting. Among these patients, 30 were followed-up with intravascular ultrasonography. Data were analyzed in a laboratory of quantitative analysis by means of a specific software. RESULTS: Sixteen (53.3% patients were men, and 14 (46.7%, women, and the mean age was 60

  1. Cirugía de revascularización miocárdica versus stent farmacoactivos en pacientes con enfermedad de tronco común izquierdo: una revisión sistemática de ensayos clínicos aleatorizados y de metaanálisis de ensayos clínicos aleatorizados

    Directory of Open Access Journals (Sweden)

    Stefano Urso

    2018-03-01

    Full Text Available Resumen: Objetivo: El objetivo de la presente revisión sistemática es analizar en la literatura los resultados clínicos de cirugía de revascularización coronaria versus la intervención coronaria percutánea con stent farmacoactivos en el tratamiento de la enfermedad del tronco común izquierdo. Métodos: Se realizó una búsqueda bibliográfica mediante las bases de datos de Pubmed, Google Scholar, Medline, Embase y Cochrane, restringiendo dicha búsqueda a ensayos clínicos aleatorizados o metaanálisis realizados sobre ensayos clínicos aleatorizados, sin restricción de año de publicación ni de idioma. Resultados: Ochenta y dos artículos fueron encontrados usando la metodología de búsqueda descrita. De estos, fueron seleccionados 7 artículos procedentes de 5 ensayos de no inferioridad (SYNTAX, PRECOMBAT, estudio de Boudriot et al., NOBLE y EXCEL y 7 metaanálisis. Los presentes ensayos han comparado stent farmacoactivos de primera generación (SYNTAX: stent con paclitaxel; ensayo de Boudriot et al. y PRECOMBAT: stent con sirolimus y stents farmacoactivos de segunda generación (NOBLE: stent con biolimus; EXCEL: stent con everolimus con cirugía.Con referencia al procedimiento de revascularización coronaria, la utilización de la doble arteria mamaria interna osciló entre el 7,4 y el 54,4%. Todos los ensayos clínicos incluidos en esta revisión reportaron una tasa estadísticamente menor de revascularización repetida en la población quirúrgica. De acuerdo con la revisión de metaanálisis, el riesgo, expresado como razón de probabilidades, de requerir un nuevo procedimiento de revascularización miocárdica por la población percutánea en comparación con el de la población quirúrgica osciló entre 1,68 y 2,21. Conclusiones: Independientemente del tipo de stent farmacoactivo utilizado en los procedimientos percutáneos y a pesar de la baja tasa de utilización de la doble arteria mamaria interna en el grupo quir

  2. Esophagoenteral stents in patients with recurrent gastric adenocarcinoma Prótesis esofagoenterales en pacientes con recidiva de adenocarcinoma gástrico

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    F. Pérez-Roldán

    2006-05-01

    Full Text Available One of the problems that can appear in patients with total gastrectomy for adenocarcinoma with esophagoenteral anastomosis is the appearance of a stenosis of the anastomosis. These stenosis are frequently malignant due to relapse of neoplasia. The therapeutic possibilities available are the surgical bypass or palliative treatment. There is very little experience described in the literature (21 cases on the placing of self-expandable metal stents as a palliative treatment for the symptoms of stenosis. We present our experience of 3 patients, in whom 4 esophageal stents were fitted (1 covered and 3 uncovered with good results. The dysphagia disappeared or improved, it allowed the ingestion of a soft diet and meant an improvement in the quality of life and at the same time stopped the weight loss. It seems an effective palliative treatment as a treatment for dysphagia in patients with tumoral relapse in the anastomosis of total gastrectomies.Uno de los problemas que puede aparecer en los pacientes con gastrectomía total por adenocarcinoma con anastomosis esofagoenteral es la aparición de estenosis de la anastomosis o próxima a ella. Estas estenosis con frecuencia son malignas debido a la aparición de recidiva en la neoplasia. Las posibilidades terapéuticas de las que disponemos son el bypass quirúrgico o bien el tratamiento paliativo. Existe muy poca experiencia descrita en la literatura (21 casos sobre la colocación de prótesis metálicas autoexpandibles como tratamiento paliativo de los síntomas de la estenosis. Presentamos nuestra experiencia en 3 pacientes, en los que se colocaron 4 prótesis esofágicas (1 recubierta y 3 no recubiertas con buenos resultados. Desapareció o mejoró la disfagia, permitió la ingesta de dieta blanda y supuso una mejora en la calidad de vida a la vez que impide la pérdida ponderal. Parece un tratamiento paliativo eficaz como tratamiento de la disfagia en pacientes con recidiva tumoral en la anastomosis

  3. Experiencia con hipotermia terapéutica en el paro cardíaco extrahospitalario

    Directory of Open Access Journals (Sweden)

    Ricardo Levin

    2016-01-01

    Full Text Available Introducción: El paro cardíaco extrahospitalario (PCEH, una de las principales causas de mortalidad en el mundo occidental, se asocia con una muy baja sobrevida hospitalaria y con un número elevado de secuelas neurológicas entre los sobrevivientes, sin modificaciones significativas en el pronóstico en las últimas tres décadas. Estudios clínicos más recientes plantearon la utilidad de la hipotermia terapéutica en la reducción de la mortalidad y el grado de deterioro neurológico en sobrevivientes de un PCEH. Objetivos: Evaluar la mortalidad y el resultado neurológico de pacientes comatosos resucitados de un PCEH tratados con hipotermia terapéutica. Considerar las indicaciones y los hallazgos de la cinecoronariografía y detectar complicaciones asociadas con la hipotermia. Material y métodos: Se incluyeron pacientes resucitados de un PCEH tratados bajo hipotermia terapéutica, que consistió en una fase de enfriamiento a 33 °C, un mantenimiento durante 24 horas y recalentamiento a 0,25 °C/hora. Se analizaron las indicaciones y los hallazgos de la cinecoronariografía. Se evaluaron complicaciones metabólicas, arrítmicas, infecciosas y hemorrágicas. Se consideró significativo valor de p menor de 0,05. Resultados: De los 213 pacientes incluidos, la sobrevida hospitalaria fue de 109 pacientes (51,2%, de los que 96 (46,1% presentaron al egreso buena recuperación neurológica. Se observó mayor sobrevida en pacientes con ritmos pasibles de desfibrilación respecto de aquellos con ritmos no pasibles de desfibrilación (58,2% vs. 37,7%; p = 0,007. Se derivaron (3,5 horas en promedio a cinecoronariografía 147 (69% pacientes, de los cuales 121 (82,3% mostraron enfermedad significativa, observándose en 69 (57% oclusión coronaria completa. Ciento siete pacientes fueron sometidos a angioplastia; 43 (40,2% de ellos fallecieron durante la internación frente a 61 (58,6% óbitos entre los no intervenidos o no estudiados (p = 0,005. Entre

  4. Drug eluting stents and modern stent technologies for in-stent restenosis.

    Science.gov (United States)

    Werner, Martin

    2017-08-01

    The implantation of metallic stents has become a standard procedure to improve the outcome after angioplasty of peripheral vessels. However, the occurrence of in-stent restenosis is hampering the long-term efficacy of these procedures and is associated with re-occurrence of symptoms. The optimal treatment modality for in-stent-restenosis in the peripheral vasculature is not well examined. This review discusses the existing evidence for the treatment of in-stent restenosis with drug eluting stents and modern stent technologies.

  5. Accidente cerebrovascular isquémico asociado con ablación por radiofrecuencia de reentrada nodal Ischemic stroke associated with radio frequency ablation for nodal reentry

    Directory of Open Access Journals (Sweden)

    Juan C Díaz Martínez

    2010-04-01

    Full Text Available La taquicardia por reentrada nodal es la causa más común de taquicardia supraventricular paroxística; en aquellos pacientes en quienes el manejo farmacológico no es efectivo o deseado la ablación por radiofrecuencia es un excelente método terapéutico dada su alta tasa de curación. Aunque en términos generales dichos procedimientos son rápidos y seguros, se han descrito varias complicaciones entre las que sobresale el accidente cerebrovascular isquémico. Se presenta el caso de una paciente de 41 años con episodios de taquicardia por reentrada nodal a repetición, que fue llevada a ablación por radiofrecuencia. En el post-operatorio inmediato se evidenció déficit neurológico focal con isquemia en el territorio de la arteria cerebral media derecha, tras lo cual se realizó angiografía con intento de angioplastia y abxicimab y posteriormente infusión local de activador de plasminógeno tisular (rtPA con adecuado resultado clínico y angiográfico.Atrioventricular nodal reentry tachycardia is the most common type of paroxismal supraventricular tachycardia. In those patients in whom drug therapy is not effective or not desired, radio frequency ablation is an excellent therapeutic method. Although overall these procedures are fast and safe, several complications among which ischemic stroke stands out, have been reported. We present the case of a 41 year old female patient with repetitive episodes of tachycardia due to nodal reentry who was treated with radiofrequency ablation. Immediately after the procedure she presented focal neurologic deficit consistent with ischemic stroke in the right medial cerebral artery territory. Angiography with angioplastia and abxicimab was performed and then tissue plasminogen activator (rtPA was locally infused, with appropriate clinical and angiographic outcome.

  6. Spectral Imaging for Intracranial Stents and Stent Lumen.

    Science.gov (United States)

    Weng, Chi-Lun; Tseng, Ying-Chi; Chen, David Yen-Ting; Chen, Chi-Jen; Hsu, Hui-Ling

    2016-01-01

    Application of computed tomography for monitoring intracranial stents is limited because of stent-related artifacts. Our purpose was to evaluate the effect of gemstone spectral imaging on the intracranial stent and stent lumen. In vitro, we scanned Enterprise stent phantom and a stent-cheese complex using the gemstone spectral imaging protocol. Follow-up gemstone spectral images of 15 consecutive patients with placement of Enterprise from January 2013 to September 2014 were also retrospectively reviewed. We used 70-keV, 140-keV, iodine (water), iodine (calcium), and iodine (hydroxyapatite) images to evaluate their effect on the intracranial stent and stent lumen. Two regions of interest were individually placed in stent lumen and adjacent brain tissue. Contrast-to-noise ratio was measured to determine image quality. The maximal diameter of stent markers was also measured to evaluate stent-related artifact. Two radiologists independently graded the visibility of the lumen at the maker location by using a 4-point scale. The mean of grading score, contrast/noise ratio and maximal diameter of stent markers were compared among all modes. All results were analyzed by SPSS version 20. In vitro, iodine (water) images decreased metallic artifact of stent makers to the greatest degree. The most areas of cheese were observed on iodine (water) images. In vivo, iodine (water) images had the smallest average diameter of stent markers (0.33 ± 0.17mm; P stent lumen (160.03 ±37.79; P stent-related artifacts of Enterprise and enhance contrast of in-stent lumen. Spectral imaging may be considered a noninvasive modality for following-up patients with in-stent stenosis.

  7. 'Stent in a stent'--an alternative technique for removing partially covered stents following sleeve gastrectomy complications.

    Science.gov (United States)

    Vasilikostas, Georgios; Sanmugalingam, Nimalan; Khan, Omar; Reddy, Marcus; Groves, Chris; Wan, Andrew

    2014-03-01

    Endoscopic stenting is a relatively new technique for the treatment of post sleeve gastrectomy complications. Partially covered stents are used in this method to minimise the risk of migration but they are associated with difficulties with removal. Patients requiring emergency stenting following sleeve gastrectomy underwent insertion of a partially covered metallic stent. One month later, if the stent was not easily removable, a fully covered overlapping stent was inserted and the patient was readmitted 2 weeks later for removal of both stents. Four patients required stenting following sleeve gastrectomy leaks, and one patient required stenting for a stricture. In these cases, a 'stent in a stent' technique was used for removal. This technique allows the safe removal of partially covered stents inserted following sleeve gastrectomy complications.

  8. Predictors of early stent occlusion among plastic biliary stents.

    Science.gov (United States)

    Khashab, Mouen A; Kim, Katherine; Hutfless, Susan; Lennon, Anne Marie; Kalloo, Anthony N; Singh, Vikesh K

    2012-09-01

    A major disadvantage of plastic biliary stents is their short patency rates. The aim of this study was to identify predictors of early stent occlusion among patients receiving conventional plastic biliary stents. Early stent occlusion was defined as worsening cholestatic liver test results of a severity sufficiently significant to warrant ERCP with stent exchange prior to the planned stent exchange, or as symptoms of cholangitis. The association of cumulative stent diameter, demographics, stricture location, procedure indication, Charlson comorbidity index, history of prior early stent occlusion, presence of gallbladder, and performance of sphincteromy with the occurrence of early stent occlusion was studied using logistic regression and multivariate analysis. Our patient cohort comprised 343 patients (mean age 59.3 years) who underwent 561 ERCP procedures with the placement of one or more plastic biliary stents (mean number of stents per procedure 1.2, mean total diameter of stents per procedure 12 Fr). Early stent occlusion occurred in 73 (13 %) procedures. Female gender was protective against early stent occlusion (adjusted OR 0.54, 95 % CI 0.32-0.90, p = 0.02), while hilar stricture location was independently associated with a significantly increased risk of early stent occlusion (adjusted OR 3.41, 95 % CI 1.68-6.90, p = 0.0007). Early occlusion of conventional biliary stents occurred in 13 % of cases. While female gender decreased the risk of early stent occlusion, hilar stricture location was a significant predictor of early stent occlusion. Our results suggest that physicians should consider early elective stent exchange in patients with hilar strictures.

  9. Delayed complications after flow-diverter stenting: reactive in-stent stenosis and creeping stents.

    Science.gov (United States)

    Cohen, José E; Gomori, John Moshe; Moscovici, Samuel; Leker, Ronen R; Itshayek, Eyal

    2014-07-01

    We assessed the frequency and severity of changes in stent configuration and location after the treatment of intracranial aneurysms, and patterns of in-stent stenosis. We retrospectively reviewed data for consecutive aneurysm patients managed with endovascular implantation of flow-diverter stents (Silk Flow Diverter [Balt Extrusion, Montmorency, France] and Pipeline Embolization Device [ev3/Coviden, Minneapolis, MN, USA]) from October 2011 to July 2012. Routine 2, 6, 9-12, and 16-20 month follow-up angiograms were compared, with a focus on changes in stent configuration and location from immediately after deployment to angiographic follow-up, and the incidence and development of in-stent stenosis. Thirty-four patients with 42 aneurysms met inclusion criteria. The Silk device was implanted in 16 patients (47%, single device in 15), the Pipeline device in 18 (53%, single device in 16). On first follow-up angiography, in-stent stenosis was observed in 38% of Silk devices and 39% of Pipeline devices. In-stent stenosis was asymptomatic in 12 of 13 patients. One woman presented with transient ischemic attacks and required stent angioplasty due to end tapering and mild, diffuse in-stent stenosis. Configuration and location changes, including stent creeping and end tapering were seen in 2/16 patients (13%) with Silk devices, and 0/18 patients with Pipeline devices. We describe stent creeping and end tapering as unusual findings with the potential for delayed clinical complications. In-stent stenosis, with a unique behavior, is a frequent angiographic finding observed after flow-diverter stent implant. The stenosis is usually asymptomatic; however, close clinical and angiographic monitoring is mandatory for individualized management. Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. The risk and prognostic impact of definite stent thrombosis or in-stent restenosis after coronary stent implantation

    DEFF Research Database (Denmark)

    Thayssen, Per; Jensen, Lisette Okkels; Lassen, Jens Flensted

    2012-01-01

    Aims: Data are limited on the prognostic impact of stent thrombosis and in-stent restenosis in patients treated with coronary stents. We examined the prognostic impact of stent thrombosis and in-stent restenosis in patients treated with percutaneous coronary intervention (PCI). Methods and results......: All patients who underwent stent implantation from 2002 to 2005 were identified in the Western Denmark Heart Registry. The hazard ratio (HR) for death associated with stent thrombosis or in-stent restenosis was estimated with a Cox regression analysis with stent thrombosis or in-stent restenosis...... as time-dependent variables. A total of 12,277 patients were treated with stent implantation. Stent thrombosis was observed in 111 (0.9%) patients and in-stent restenosis in 503 (4.1%) patients within 12 months after the index PCI. Occurrence of stent thrombosis was associated with an increased risk...

  11. Expandable stents.

    Science.gov (United States)

    Nesbitt, J C; Carrasco, H

    1996-05-01

    Expandable metallic stents are effective in selected patients with malignant or benign airway stenoses. When used for malignant lesions, the primary purpose of the stent is to improve the quality of life; stents are usually chosen for palliation of symptoms in recognition of the low likelihood of success for other therapy. For patients with benign stenoses, the stents provide a permanent source of structural support to alleviate the narrowed segment. The advantages of the expandable metallic stents are as follows: (1) they can be inserted through an endotracheal tube or under local anesthesia with relative simplicity under fluoroscopic guidance; (2) they do not impair the drainage of sputum because ciliary movement is not interrupted; (3) over a period of a few weeks, the meshwork is gradually covered with mucosa as the stent becomes incorporated into the airway wall; (4) ventilation usually is not impaired if the metallic mesh stent covers another nonstenosed bronchus, because the interstices of the stent are nonobstructive; and (5) they are dynamic and continue to expand over time, particularly if concurrent treatment achieves an effect on the lesion that caused stenosis. Disadvantages of the expandable stent include (1) they often are only temporarily effective for tracheobronchial stenosis due to intraluminal tumor or granulation tissue, both of which can grow between the wires; (2) they are considered permanent stents because removal is difficult; and (3) they can be poorly positioned during placement or can become displaced by progressive migration after placement, and they cannot be repositioned. A relative contraindication to insertion is an inflammatory process or infection that can predispose to granulation formation, particularly at the points of maximal contact pressure of the stent to the airway mucosa. In the presence of inflammation, it may be better to use a silicone prosthesis until the inflammatory process subsides and fibrosis occurs. Granulation

  12. Fractura de stent sirolimus: una causa de restenosis tardía

    Directory of Open Access Journals (Sweden)

    William Amaya

    2013-12-01

    Full Text Available El primer caso de fractura de stent farmacológico en arterias coronarias fue publicado en 2004, y aunque es un evento infrecuente, las implicaciones diagnósticas y terapéuticas siguen siendo un reto. Se presenta el caso de un paciente de género masculino, de 49 años de edad, portador de dos stents medicados, con antedecedente de nuevo evento coronario y diagnóstico de fractura de dichos dispositivos a través de cateterismo.

  13. Long-term results after carotid artery stenting. Restenosis after carotid artery stenting using self-expandable stent

    International Nuclear Information System (INIS)

    Matsumoto, Yasushi; Furui, Eisuke; Tsuboi, Ken; Takahashi, Akira; Ezura, Masayuki

    2008-01-01

    Carotid artery stenting has emerged as an acceptable treatment alternative in patients with carotid artery stenosis. Although early clinical results of carotid artery stenting have shown promise, long, term clinical results remain less certain. We report the frequency, management, and clinical results of in-stent restenosis after carotid artery stenting using a self-expandable stent. Between August 1998 and September 2004, 80 carotid artery stenting procedures in 78 patients were performed. We evaluated 76 of the 80 procedures in 75 of the 78 patients treated during this period who had a minimum 6-month clinical and imaging (ultrasound and/or magnetic resonance angiography) follow-up. Recurrent stenosis (≥50%) after carotid artery stenting occurred in 3 (3.9%) patients. The recurrent stenosis occurred within one year after the procedure in all cases. The low rate of in-stent restenosis using self-expandable stent suggested that carotid artery stenting may be an effective alternative treatment for carotid artery stenosis, but more data of long-term follow-up are required. (author)

  14. Stent fabric fatigue of grafts supported by Z-stents versus ringed stents: an in vitro buckling test.

    Science.gov (United States)

    Lin, Jing; Wang, Lu; Guidoin, Robert; Nutley, Mark; Song, Ge; Zhang, Ze; Du, Jia; Douville, Yvan

    2014-03-01

    Stent-grafts externally fitted with a Z-shaped stents were compared to devices fitted with ringed stents in an in vitro oscillating fatigue machine at 200 cycles per minute and a pressure of 360 mmHg for scheduled durations of up to 1 week. The devices fitted with Z-stents showed a considerably lower endurance limit to buckling compared to the controls. The contact between the apexes of adjacent Z-stents resulted in significant damage to the textile scaffolds and polyester fibers due to the sharp angle of the Z-stents. The ringed stents did not cause any fraying in the textile scaffolds.

  15. The effect of stent coating on stent deliverability: direct randomised comparison of drug eluting and bare metal stents using the same stent platform.

    Science.gov (United States)

    Siminiak, Tomasz; Link, Rafał; Wołoszyn, Maciej; Kałmucki, Piotr; Baszko, Artur

    2012-01-01

    There is certain experimental and clinical evidence indicating that the covering of bare metal stents (BMS) with drug eluting polymers to produce drug eluting stents (DES) results in increased stent stiffness and modifies the mechanical properties of the stent platform. In addition, it has been speculated that the mechanical performance of DES, compared to BMS, may be related to the type of polymer used to cover stents. We aimed at evaluating the deliverability of DES with a lactate based biodegradable polymer and BMS in patients with stable coronary artery disease in a prospective randomised study. One hundred eleven consecutive patients (age: 36-77, mean 58.8 years) scheduled for routine angioplasty due to stable coronary disease were randomised to receive BMS (Chopin II(TM), Balton, Poland) or paclitaxel eluting stent (Chopin Luc(TM), Balton, Poland) using the same metal platform. Only patients scheduled for angioplasty using the direct implantation technique of a single stent were randomised. The exclusion criteria included patients 〉 80 years, multivessel disease and reference diameter of the target vessel 〉 3.5 mm. In the BMS group (n = 55; 35 males and 20 females), the mean diameter of implanted stents was 3.09 ± 0.40 and the mean length was 11.37 ± 2.80, whereas in the DES group (n = 56; 34 males and 22 females) the mean stent sizes were 3.02 ± 0.34 and 17.90 ± 7.38 mm, respectively (p 〉 0.05 for length). The groups did not significantly differ regarding the frequency of stent implantation to particular coronary vessels. The direct stenting technique was attempted and failed, leading to the stents' implantation after predilatation in five patients in the BMS group and six patients in the DES group. Failure of stent implantation and subsequent implantation of another stent type was observed in no BMS patients and in one DES patient (NS). Although stent covering with lactate based drug eluting polymer may increase its stiffness, it does not affect

  16. Drug-eluting stents to prevent stent thrombosis and restenosis.

    Science.gov (United States)

    Im, Eui; Hong, Myeong-Ki

    2016-01-01

    Although first-generation drug-eluting stents (DES) have significantly reduced the risk of in-stent restenosis, they have also increased the long-term risk of stent thrombosis. This safety concern directly triggered the development of new generation DES, with innovations in stent platforms, polymers, and anti-proliferative drugs. Stent platform materials have evolved from stainless steel to cobalt or platinum-chromium alloys with an improved strut design. Drug-carrying polymers have become biocompatible or biodegradable and even polymer-free DES were introduced. New limus-family drugs (such as everolimus, zotarolimus or biolimus) were adopted to enhance stent performances. As a result, these new DES demonstrated superior vascular healing responses on intracoronary imaging studies and lower stent thrombotic events in actual patients. Recently, fully-bioresorbable stents (scaffolds) have been introduced, and expanding their applications. In this article, the important concepts and clinical results of new generation DES and bioresorbable scaffolds are described.

  17. Intravascular ultrasound assessed incomplete stent apposition and stent fracture in stent thrombosis after bare metal versus drug-eluting stent treatment the Nordic Intravascular Ultrasound Study (NIVUS)

    DEFF Research Database (Denmark)

    Kosonen, Petteri; Vikman, Saila; Jensen, Lisette Okkels

    2012-01-01

    This prospective multicenter registry used intravascular ultrasound (IVUS) in patients with definite stent thrombosis (ST) to compare rates of incomplete stent apposition (ISA), stent fracture and stent expansion in patients treated with drug-eluting (DES) versus bare metal (BMS) stents. ST...... is a rare, but potential life threatening event after coronary stent implantation. The etiology seems to be multifactorial....

  18. An in Vitro Twist Fatigue Test of Fabric Stent-Grafts Supported by Z-Stents vs. Ringed Stents

    Directory of Open Access Journals (Sweden)

    Jing Lin

    2016-02-01

    Full Text Available Whereas buckling can cause type III endoleaks, long-term twisting of a stent-graft was investigated here as a mechanism leading to type V endoleak or endotension. Two experimental device designs supported with Z-stents having strut angles of 35° or 45° were compared to a ringed control under accelerated twisting. Damage to each device was assessed and compared after different durations of twisting, with focus on damage that may allow leakage. Stent-grafts with 35° Z-stents had the most severe distortion and damage to the graft fabric. The 45° Z-stents caused less fabric damage. However, consistent stretching was still seen around the holes for sutures, which attach the stents to the graft fabric. Larger holes may become channels for fluid percolation through the wall. The ringed stent-graft had the least damage observed. Stent apexes with sharp angles appear to be responsible for major damage to the fabrics. Device manufacturers should consider stent apex angle when designing stent-grafts, and ensure their devices are resistant to twisting.

  19. An in Vitro Twist Fatigue Test of Fabric Stent-Grafts Supported by Z-Stents vs. Ringed Stents.

    Science.gov (United States)

    Lin, Jing; Guidoin, Robert; Du, Jia; Wang, Lu; Douglas, Graeham; Zhu, Danjie; Nutley, Mark; Perron, Lygia; Zhang, Ze; Douville, Yvan

    2016-02-16

    Whereas buckling can cause type III endoleaks, long-term twisting of a stent-graft was investigated here as a mechanism leading to type V endoleak or endotension. Two experimental device designs supported with Z-stents having strut angles of 35° or 45° were compared to a ringed control under accelerated twisting. Damage to each device was assessed and compared after different durations of twisting, with focus on damage that may allow leakage. Stent-grafts with 35° Z-stents had the most severe distortion and damage to the graft fabric. The 45° Z-stents caused less fabric damage. However, consistent stretching was still seen around the holes for sutures, which attach the stents to the graft fabric. Larger holes may become channels for fluid percolation through the wall. The ringed stent-graft had the least damage observed. Stent apexes with sharp angles appear to be responsible for major damage to the fabrics. Device manufacturers should consider stent apex angle when designing stent-grafts, and ensure their devices are resistant to twisting.

  20. Stent

    Science.gov (United States)

    ... Drugs & Supplements Videos & Tools Español You Are Here: Home → Medical Encyclopedia → Stent URL of this page: //medlineplus.gov/ency/article/002303.htm Stent To use the sharing features on this page, please enable JavaScript. A stent is a tiny tube placed into a hollow structure in your ...

  1. Symptomatic stent cast.

    LENUS (Irish Health Repository)

    Keohane, John

    2012-02-03

    Biliary stent occlusion is a major complication of endoscopic stent insertion and results in repeat procedures. Various theories as to the etiology have been proposed, the most frequently studied is the attachment of gram negative bacteria within the stent. Several studies have shown prolongation of stent patency with antibiotic prophylaxis. We report the case of stent occlusion from a cast of a previously inserted straight biliary stent; a "stent cast" in an 86-year-old woman with obstructive jaundice. This was retrieved with the lithotrypter and she made an uneventful recovery. This is the first reported case of a biliary stent cast.

  2. Primary and revision efficacy of cross-wired metallic stents for endoscopic bilateral stent-in-stent placement in malignant hilar biliary strictures.

    Science.gov (United States)

    Lee, T H; Moon, J H; Kim, J H; Park, D H; Lee, S S; Choi, H J; Cho, Y D; Park, S H; Kim, S J

    2013-01-01

    Endoscopic bilateral drainage for inoperable malignant hilar biliary strictures (HBS) using metal stents is considered to be technically difficult. Furthermore, endoscopic revision of bilateral stenting after occlusion can be challenging. This study was performed to evaluate the long-term efficacy of endoscopic bilateral stent-in-stent placement of cross-wired metallic stents in high-grade malignant HBS and planned endoscopic bilateral revision. A total of 84 patients with inoperable high-grade malignant HBS were enrolled from three academic tertiary referral centers. Two cross-wired metal stents were inserted using a bilateral stent-in-stent placement method. Bilateral endoscopic revision was also performed during follow-up using either identical metal stents or plastic stents. The main outcome measurements were technical and functional success, complications, stent patency, and endoscopic revision efficacy. The technical and clinical success rates of endoscopic bilateral stent-in-stent placement of cross-wired metallic stents were 95.2% (80/84) and 92.9% (78/84), respectively. Median patency (range) and survival were 238 days (10-429) and 256 days (10-1130), respectively. Obstruction of primary bilateral stents occurred in 30.8% (24/78) of patients with functionally successful stent placement. The technical and clinical success rates of planned bilateral endoscopic revision for occluded stents were 83.3% (20/24) and 79.2% (19/24), respectively. For revision, bilateral metallic stents were placed in 11 patients (55.0%); the remaining patients received plastic stents. Palliative endoscopic bilateral stent-in-stent placement of cross-wired metallic stents was effective in patients with inoperable HBS. Revision endoscopic bilateral stenting may be feasible and successful in cases where the primary deployed metal stents are occluded. © Georg Thieme Verlag KG Stuttgart · New York.

  3. Circumferential Stent Fracture: Novel Detection and Treatment with the Use of StentBoost

    OpenAIRE

    Ramegowda, Raghu T.; Chikkaswamy, Srinivas B.; Bharatha, Ashalatha; Radhakrishna, Jayashree; Krishnanaik, Geetha B.; Nanjappa, Manjunath C.; Panneerselvam, Arunkumar

    2012-01-01

    Circumferential stent fracture is extremely uncommon, and in rare cases, it can cause stent thrombosis. Recognizing stent fracture can be difficult on conventional fluoroscopy because of poor stent radiopacity. We found that StentBoost image acquisition yields improved visibility of stent struts, enabling the identification of stent fracture and the precise positioning of new stents over previously stented segments.

  4. Metallic ureteral stents in malignant ureteral obstruction: clinical factors predicting stent failure.

    Science.gov (United States)

    Chow, Po-Ming; Hsu, Jui-Shan; Huang, Chao-Yuan; Wang, Shuo-Meng; Lee, Yuan-Ju; Huang, Kuo-How; Yu, Hong-Jheng; Pu, Yeong-Shiau; Liang, Po-Chin

    2014-06-01

    To provide clinical outcomes of the Resonance metallic ureteral stent in patients with malignant ureteral obstruction, as well as clinical factors predicting stent failure. Cancer patients who have received Resonance stents from July 2009 to March 2012 for ureteral obstruction were included for chart review. Stent failure was detected by clinical symptoms, image studies, and renal function tests. Survival analysis for stent duration was used to estimate patency rate and factors predicting stent failure. A total of 117 stents were inserted successfully into 94 ureteral units in 79 patients. There were no major complications. These stents underwent survival analysis and proportional hazard regression. The median duration for the stents was 5.77 months. In multivariate analysis, age (P=0.043), preoperative serum creatinine level (P=0.0174), and cancer type (P=0.0494) were significant factors associated with stent failure. Cancer treatment before and after stent insertion had no effect on stent duration. Resonance stents are effective and safe in relieving malignant ureteral obstructions. Old age and high serum creatinine level are predictors for stent failure. Stents in patients with lower gastrointestinal cancers have longer functional duration.

  5. The Effect of Stent Cell Geometry on Carotid Stenting Outcomes

    Energy Technology Data Exchange (ETDEWEB)

    Alparslan, Burcu, E-mail: burcu.alparslan@gmail.com [Yozgat State Hospital, Radiology Clinic (Turkey); Nas, Omer Fatih, E-mail: omerfatihnas@gmail.com [Uludag University Faculty of Medicine, Department of Radiology (Turkey); Eritmen, Ulku Turpcu, E-mail: drulkutur@hotmail.com.tr [Special Eregli Anatolia Hospital, Radiology Clinic (Turkey); Duran, Selcen, E-mail: selcenduran16@hotmail.com [Yerkoy State Hospital, Neurology Clinic (Turkey); Ozkaya, Guven, E-mail: ozkaya@uludag.edu.tr [Uludag University Faculty of Medicine, Department of Biostatistics (Turkey); Hakyemez, Bahattin, E-mail: bhakyemez@uludag.edu.tr [Uludag University Faculty of Medicine, Department of Radiology (Turkey)

    2016-04-15

    PurposeThe aim of this study was to investigate the effect of stent cell geometry on midterm results of carotid artery stenting (CAS).Materials and MethodOne hundred fifty-five patients underwent CAS between February 2010 and December 2012. Ninety-one open- and 84 closed-cell stents were used in this non-randomized, retrospective study. Periprocedural complications were defined as the ones happened during the procedure or within 30 days afterwards. Starting from the 6th month after the procedure, in-stent restenosis was detected with multidetector computed tomography angiography and classified into four groups from focal restenosis to occlusion.ResultsEleven complications were encountered in the periprocedural period (four on the open- and seven on the closed-cell group). Total complication rate was 6.3 % (11/175). No significant difference was detected in terms of periprocedural complications between two groups (p = 0.643). There was statistically significant difference between stent design groups in regard to radiological findings (p = 0.002). Sixteen of open-cell stents and three of closed-cell stents had focal restenosis. One closed-cell stent had diffuse proliferative restenosis and one open-cell stent had total occlusion.ConclusionIn-stent restenosis was more common in open-cell stent group, which have larger free cell area than closed-cell stents. Although our radiologic findings promote us to use closed-cell design if ‘possible’, no difference was detected in terms of clinical outcomes.

  6. Radial force measurement of endovascular stents: Influence of stent design and diameter.

    Science.gov (United States)

    Matsumoto, Takuya; Matsubara, Yutaka; Aoyagi, Yukihiko; Matsuda, Daisuke; Okadome, Jun; Morisaki, Koichi; Inoue, Kentarou; Tanaka, Shinichi; Ohkusa, Tomoko; Maehara, Yoshihiko

    2016-04-01

    Angioplasty and endovascular stent placement is used in case to rescue the coverage of main branches to supply blood to brain from aortic arch in thoracic endovascular aortic repair. This study assessed mechanical properties, especially differences in radial force, of different endovascular and thoracic stents. We analyzed the radial force of three stent models (Epic, E-Luminexx and SMART) stents using radial force-tester method in single or overlapping conditions. We also analyzed radial force in three thoracic stents using Mylar film testing method: conformable Gore-TAG, Relay, and Valiant Thoracic Stent Graft. Overlapping SMART stents had greater radial force than overlapping Epic or Luminexx stents (P stents was greater than that of all three endovascular stents (P stents, site of deployment, and layer characteristics. In clinical settings, an understanding of the mechanical characteristics, including radial force, is important in choosing a stent for each patient. © The Author(s) 2015.

  7. Predictors of stent dysfunction after self-expandable metal stent placement for malignant gastric outlet obstruction: tumor ingrowth in uncovered stents and migration of covered stents.

    Science.gov (United States)

    Hori, Yasuki; Naitoh, Itaru; Hayashi, Kazuki; Ban, Tesshin; Natsume, Makoto; Okumura, Fumihiro; Nakazawa, Takahiro; Takada, Hiroki; Hirano, Atsuyuki; Jinno, Naruomi; Togawa, Shozo; Ando, Tomoaki; Kataoka, Hiromi; Joh, Takashi

    2017-10-01

    Endoscopic metallic stenting is widely accepted as a palliation therapy for malignant gastric outlet obstruction (GOO). However, the predictors of stent dysfunction have not been clarified. We aimed to evaluate the predictors, especially tumor ingrowth in uncovered self-expandable metallic stents (U-SEMS) and migration of covered self-expandable metallic stents (C-SEMS), which are the main causes related to the stent characteristics. In this multicenter retrospective study, we compared patients with U-SEMS and C-SEMS in terms of clinical outcomes, and predictors of stent dysfunction. In total, 252 patients (126 with U-SEMS and 126 with C-SEMS) were enrolled. There were no significant differences in technical success, clinical success, GOO score, or time to stent dysfunction. Tumor ingrowth was significantly more frequent in U-SEMS (U-SEMS, 11.90% vs. C-SEMS, 0.79%; p = 0.002), and stent migration was significantly more frequent for C-SEMS (C-SEMS, 8.73% vs. U-SEMS, 0.79%; p = 0.005). Karnofsky performance status (p = 0.04), no presence of ascites (p = 0.02), and insufficient (stent expansion (p = 0.003) were significantly associated with tumor ingrowth in U-SEMS. Meanwhile, a shorter stent length (p = 0.05) and chemotherapy (p = 0.03) were predictors of C-SEMS migration. Both U-SEMS and C-SEMS are effective with comparable patencies. Tumor ingrowth and stent migration are the main causes of stent dysfunction for U-SEMS and C-SEMS, respectively. With regard to stent dysfunction, U-SEMS might be a good option for patients receiving chemotherapy, while C-SEMS with longer stents for patients in good condition. (Clinical trial registration number: UMIN000024059).

  8. Airway stents

    Science.gov (United States)

    Keyes, Colleen

    2018-01-01

    Stents and tubes to maintain the patency of the airways are commonly used for malignant obstruction and are occasionally employed in benign disease. Malignant airway obstruction usually results from direct involvement of bronchogenic carcinoma, or by extension of carcinomas occurring in the esophagus or the thyroid. External compression from lymph nodes or metastatic disease from other organs can also cause central airway obstruction. Most malignant airway lesions are surgically inoperable due to advanced disease stage and require multimodality palliation, including stent placement. As with any other medical device, stents have significantly evolved over the last 50 years and deserve an in-depth understanding of their true capabilities and complications. Not every silicone stent is created equal and the same holds for metallic stents. Herein, we present an overview of the topic as well as some of the more practical and controversial issues surrounding airway stents. We also try to dispel the myths surrounding stent removal and their supposed use only in central airways. At the end, we come to the long-held conclusion that stents should not be used as first line treatment of choice, but after ruling out the possibility of curative surgical resection or repair. PMID:29707506

  9. Recurrence of Subacute Stent Thrombosis and In-Stent Restenosis during Five Months after Stent Implantation in the LAD. A Case Report.

    OpenAIRE

    島田, 弘英; 大和, 眞史; 櫻井, 俊平; 疋田, 博之; 池田, 修一

    2001-01-01

    A coronary stent was deployed in the left anterior descending artery of an 82-year-old woman with unstable angina.Recurrence of subacute stent thrombosis and in-stent restenosis occurred frequently during the five months after initial stent implantation.Balloon angioplasty and cutting balloon angioplasty failed to prevent these complications,but they ceased after re-stenting in the initial stent.In this case,tissue protrusion through the stent strut, deformation of the coil stent and inadequa...

  10. StentBoost Visualization for the Evaluation of Coronary Stent Expansion During Percutaneous Coronary Interventions

    OpenAIRE

    Cura, Fernando; Albertal, Mariano; Candiello, Alfonsina; Nau, Gerardo; Bonvini, Victor; Tricherri, Hernan; Padilla, Lucio T.; Belardi, Jorge A.

    2013-01-01

    Introduction Inadequate stent implantation is associated with stent thrombosis and restenosis. StentBoost can enhance stent visualization and evaluate stent expansion. Currently, there are limited comparison studies between StentBoost and intravascular ultrasound (IVUS). We aimed to test the correlation and agreement between IVUS and StentBoost measurements. Methods From December 2010 to December 2011, 38 patients (54 stents) were analyzed using IVUS and StentBoost. Minimal stent diameter and...

  11. Stent malapposition, as a potential mechanism of very late stent thrombosis after bare-metal stent implantation: A case report

    Energy Technology Data Exchange (ETDEWEB)

    Higuma, Takumi, E-mail: higuma@cc.hirosaki-u.ac.jp; Abe, Naoki; Hanada, Kenji; Yokoyama, Hiroaki; Tomita, Hirofumi; Okumura, Ken

    2014-04-15

    A 90-year-old man was admitted to our hospital with acute ST-segment elevation myocardial infarction. He had a history of post-infarction angina pectoris 79 months ago and had a bare-metal stent (BMS) implanted in the proximal left anterior descending artery at our hospital. Emergent coronary angiography demonstrated thrombotic occlusion in the previously stented segment. After catheter thrombectomy, antegrade flow was restored, but 90% stenosis with haziness persisted in the proximal and distal portions of the previously stented segment. Intravascular ultrasound imaging showed interstrut cavities or stent malapposition at the proximal and distal sites of stented segment. In close proximity to the sites, residual thrombi were also observed. Optical coherence tomography (OCT) demonstrated neither lipid-laden neointimal tissue nor rupture but clearly demonstrated residual thrombus adjacent to the malapposed region in addition to the stent malapposition. PCI with balloon was successfully performed and stent apposition was confirmed by OCT. Stent malapposition is an unusual mechanism of very late stent thrombosis after BMS implantation. OCT can clearly reveal the etiology of stent thrombosis.

  12. Incidence of definite stent thrombosis or in-stent restenosis after drug-eluting stent implantation for treatment of coronary in-stent restenosis. From western denmark heart registry

    DEFF Research Database (Denmark)

    Jensen, Jesper; Jensen, Lisette Okkels; Terkelsen, Christian Juhl

    2012-01-01

    There are limited data on the optimal management of in-stent restenosis after percutaneous coronary intervention (PCI) with bare metal stent (BMS) or drug-eluting stent (DES) implantations. We assessed the clinical presentation, the incidence, and prognosis of definite stent thrombosis...

  13. Terapia de restauración vascular con plataformas biorreabsorbibles. La cuarta revolución

    Directory of Open Access Journals (Sweden)

    Darío Echeverri

    2014-07-01

    Full Text Available Con la aprobación y concesión del Registro Sanitario 201300 4713 del 25 de febrero de 2013, con vigencia hasta el año 2023, por parte del Instituto Nacional de Vigilancia de Medicamentos y Alimentos como órgano oficial del Ministerio de Salud y Protección Social de Colombia, a la plataforma biorreabsorbible Absorb BVS®, con el nombre de stent medicado biorreabsorbible, la introducción de estas plataformas al portafolio terapéutico del cardiólogo intervencionista para el tratamiento de pacientes seleccionados con enfermedad coronaria, ha generado gran expectativa gracias a la seguridad y eficacia que han demostrado en comparación con los stents liberadores de medicamento, con resultados de no inferioridad y con el ofrecimiento de una serie de ventajas por las cuales ha sido considerado la «cuarta revolución». En este artículo se hace una revisión acerca de las plataformas existentes, de su mecanismo de acción, así como de sus potenciales ventajas y limitaciones.

  14. Risk of stent thrombosis among bare-metal stents, first-generation drug-eluting stents, and second-generation drug-eluting stents: results from a registry of 18,334 patients.

    Science.gov (United States)

    Tada, Tomohisa; Byrne, Robert A; Simunovic, Iva; King, Lamin A; Cassese, Salvatore; Joner, Michael; Fusaro, Massimiliano; Schneider, Simon; Schulz, Stefanie; Ibrahim, Tareq; Ott, Ilka; Massberg, Steffen; Laugwitz, Karl-Ludwig; Kastrati, Adnan

    2013-12-01

    This study sought to compare the risk of stent thrombosis among patients treated with bare-metal stents (BMS), first-generation drug-eluting stents (G1-DES), and second-generation drug-eluting stents (G2-DES) for a period of 3 years. In patients undergoing coronary stenting, there is a scarcity of long-term follow-up data on cohorts large enough to compare rates of stent thrombosis across the stent generations. A total of 18,334 patients undergoing successful coronary stent implantation from 1998 to 2011 at 2 centers in Munich, Germany, were included in this study. Patients were stratified into 3 groups according to treatment with BMS, G1-DES, and G2-DES. The cumulative incidence of definite stent thrombosis at 3 years was 1.5% with BMS, 2.2% with G1-DES, and 1.0% with G2-DES. On multivariate analysis, G1-DES compared with BMS showed a significantly higher risk of stent thrombosis (odds ratio [OR]: 2.05; 95% confidence interval [CI]: 1.47 to 2.86; p stent thrombosis compared with BMS (OR: 0.82; 95% CI: 0.56 to 1.19; p = 0.30). Beyond 1 year, the risk of stent thrombosis was significantly increased with G1-DES compared with BMS (OR: 4.72; 95% CI: 2.01 to 11.1; p stenting, compared with BMS, there was a significant excess risk of stent thrombosis at 3 years with G1-DES, driven by an increased risk of stent thrombosis events beyond 1 year. G2-DES were associated with a similar risk of stent thrombosis compared with BMS. Copyright © 2013 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  15. El infarto agudo de miocardio, un problema de salud pública

    OpenAIRE

    Caccavo, Alberto

    2010-01-01

    El infarto agudo de miocardio (IAM) es una causa importante de muerte en la Argentina. La mortalidad intrahospitalaria del IAM en la actualidad es de aproximadamente el 10%, al menos en los centros que participan en registros. Su tratamiento está orientado a la reperfusión de la arteria ocluida con angioplastia primaria o trombolíticos. Sin embargo, sólo un pequeño número de hospitales disponen de angioplastia primaria y reciben trombolíticos muchos menos pacientes que los que los requieren. ...

  16. Removal of retrievable self-expandable urethral stents: experience in 58 stents

    International Nuclear Information System (INIS)

    Shin, Ji Hoon; Song, Ho-Young; Kim, Jin Hyoung; Ko, Heung-Kyu; Kim, Yong Jae; Woo, Chul-Woong; Kim, Tae-Hyung; Ko, Gi-Young; Yoon, Hyun-Ki; Sung, Kyu-Bo; Park, Hyungkeun

    2006-01-01

    The purpose of this study was to retrospectively evaluate the safety and efficacy of removing retrievable self-expandable urethral stents using a retrieval hook wire. Under fluoroscopic guidance, the removal of 58 polyurethane or PTFE (polytetrafluoroethylene)-covered stents was attempted in 33 patients using a retrieval hook wire. Indications for removal were elective removal (n=21), stent migration (n=19), formation of tissue hyperplasia around or inside of the stent (n=14), stent deformity (n=3), and severe pain (n=1). The mean time the stents remained in place was 64.8±42.9 days (range, 1-177 days). Fifty-six (97%) of the 58 stents were successfully removed using the retrieval hook wire despite the following difficulties; hook wire disconnection (n=2), untied drawstrings (n=3), and polyurethane membrane disruption/separation (n=4). The removal procedure using a retrieval hook wire failed in two stents (3%) which had migrated into the urinary bladder. One of the two stents with migration into the urinary bladder was removed using a snare through the cystostomy route. The overall complication rate was 14% (seven hematuria cases and one urethral tear case), and all were minor and spontaneously resolved without further treatment. In conclusion, removal of retrievable urethral stents using a retrieval hook wire was safe and effective despite some technical difficulties. It is a useful method for allowing temporary stent placement and solving various complications of stent use. (orig.)

  17. Removal of retrievable self-expandable urethral stents: experience in 58 stents

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Ji Hoon; Song, Ho-Young; Kim, Jin Hyoung; Ko, Heung-Kyu; Kim, Yong Jae; Woo, Chul-Woong; Kim, Tae-Hyung; Ko, Gi-Young; Yoon, Hyun-Ki; Sung, Kyu-Bo [Asan Medical Center, Department of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Seoul (Korea); Park, Hyungkeun [Asan Medical Center, Department of Urology, University of Ulsan College of Medicine, Seoul (Korea)

    2006-09-15

    The purpose of this study was to retrospectively evaluate the safety and efficacy of removing retrievable self-expandable urethral stents using a retrieval hook wire. Under fluoroscopic guidance, the removal of 58 polyurethane or PTFE (polytetrafluoroethylene)-covered stents was attempted in 33 patients using a retrieval hook wire. Indications for removal were elective removal (n=21), stent migration (n=19), formation of tissue hyperplasia around or inside of the stent (n=14), stent deformity (n=3), and severe pain (n=1). The mean time the stents remained in place was 64.8{+-}42.9 days (range, 1-177 days). Fifty-six (97%) of the 58 stents were successfully removed using the retrieval hook wire despite the following difficulties; hook wire disconnection (n=2), untied drawstrings (n=3), and polyurethane membrane disruption/separation (n=4). The removal procedure using a retrieval hook wire failed in two stents (3%) which had migrated into the urinary bladder. One of the two stents with migration into the urinary bladder was removed using a snare through the cystostomy route. The overall complication rate was 14% (seven hematuria cases and one urethral tear case), and all were minor and spontaneously resolved without further treatment. In conclusion, removal of retrievable urethral stents using a retrieval hook wire was safe and effective despite some technical difficulties. It is a useful method for allowing temporary stent placement and solving various complications of stent use. (orig.)

  18. Endoscopic bilateral stent-in-stent placement for malignant hilar obstruction using a large cell type stent.

    Science.gov (United States)

    Park, Jin Myung; Lee, Sang Hyub; Chung, Kwang Hyun; Jang, Dong Kee; Ryu, Ji Kon; Kim, Yong-Tae; Lee, Jae Min; Paik, Woo Hyun

    2016-12-01

    Bilateral stent-in-stent (SIS) self-expandable metal stent placement is technically challenging for palliation of unresectable malignant hilar obstruction. In the SIS technique, the uniform large cell type biliary stent facilitates contralateral stent deployment through the mesh of the first metallic stent. This study aimed to assess the technical success and clinical effectiveness of this technique with a uniform large cell type biliary stent. Thirty-one patients who underwent bilateral SIS placement using a large cell type stent were reviewed retrospectively. All patients showed malignant hilar obstruction (Bismuth types II, III, IV) with different etiologies. Sixteen (51.6%) patients were male. The mean age of the patients was 67.0+/-14.0 years. Most patients were diagnosed as having hilar cholangiocarcinoma (58.1%) and gallbladder cancer (29.0%). Technical success rate was 83.9%. Success was achieved more frequently in patients without masses obstructing the biliary confluence (MOC) than those with MOC (95.2% vs 60.0%, P=0.03). Functional success rate was 77.4%. Complications occurred in 29.0% of the patients. These tended to occur more frequently in patients with MOC (50.0% vs 19.0%, P=0.11). Median time to recurrent biliary obstruction was 188 days and median survival was 175 days. The large cell type stent can be used efficiently for bilateral SIS placement in malignant hilar obstruction. However, the risk of technical failure increases in patients with MOC, and caution is needed to prevent complications for these patients.

  19. Self-Expandable Metal Stents and Trans-stent Light Delivery: Are Metal Stents and Photodynamic Therapy Compatible?

    Science.gov (United States)

    Wang, Luo-Wei; Li, Li-Bo; Li, Zhao-Shen; Chen, Yang K; Hetzel, Fred W.; Huang, Zheng

    2008-01-01

    Background and Objectives: Obstructive non-small cell lung cancer and obstructive esophageal cancer are US FDA approved indications of photodynamic therapy (PDT). The usefulness of PDT for the treatment of cholangiocarcinoma is currently under clinical investigation. Endoscopic stenting for lumen restoration is a common palliative intervention for those indications. It is important to assess whether self-expandable metal stents are compatible with trans-stent PDT light delivery. Study Design/Materials and Methods: Direct effects of various components of metal biliary (n = 2), esophageal (n = 2), and bronchial (n = 1) stents on PDT light transmittance and distribution were examined using a point or linear light source (630 or 652 nm diode laser). Resected pig biliary duct and esophageal wall tissues were used to examine the feasibility of PDT light delivery through the fully expanded metal stents. Results: While using a point light source, the metal components (thread and joint) of the stent could cause a significant shadow effect. The liner material (polytetrafluoroethylene or polyurethane) could cause various degrees of light absorption. When the stent was covered with a thin layer of biliary duct and esophageal tissues containing all wall layers, the shadow effect could be mitigated due to tissue scattering. Conclusions: This study clearly demonstrates that it is feasible to combine stenting and PDT for the treatment of luminal lesions. PDT light dose should be adjusted to counteract the reduction of light transmittance caused by the metal and liner materials of stent. PMID:18951422

  20. Effects of 32P radioactive stents on in-stent restenosis in a double stent injury model of the porcine coronary arteries

    International Nuclear Information System (INIS)

    Kim, Han-Soo; Chan, Rosanna C.; Kollum, Marc; Au, Arthur; Tio, Fermin O.; Yazdi, Hamid A.; Ajani, Andrew E.; Waksman, Ron

    2001-01-01

    Background: The major limitation of coronary stenting remains in-stent restenosis, due to the development of neointimal proliferation. Radioactive stents have demonstrated the ability to reduce this proliferation in the healthy nonatherosclerotic porcine animal model. However, inhibition of tissue proliferation in the in-stent restenotic lesion in a porcine model is not well characterized. The objective of this study was to examine the efficacy and safety of the 32 P radioactive stent for the treatment of in-stent restenosis in a double stent injury model of the porcine coronaries. Methods and Materials: Eighteen coronary arteries in 9 pigs underwent nonradioactive stent (8 mm in length) implantation. Thirty days after the initial stent implantation, a 32 P radioactive stent (18 mm in length) with an activity of 0 and 18 μCi was implanted to cover the initial stent. The swine were killed 30 days after the second stent implantation. Histomorphometric analysis was performed for vessel area (VA), stent strut area (SSA), intimal area (IA), and lumen area (LA). Results: Injury scores, VA, SSA, and LA were similar among the control and radiated groups. Neointimal formation was significantly reduced after placement of radioactive stents as compared to control in both the overlapped (0.93±0.12 vs. 1.31±0.51 mm 2 , p 2 , p 32 P radioactive stents may be safe and effective in reducing neointimal formation leading to in-stent restenosis. Longer follow-up will be required to examine whether these positive findings can be maintained

  1. Desfechos clínicos por região geográfica em pacientes com implante de stent eluidor de Zotarolimus Desenlaces clínicos por región geográfica en pacientes con implante de Stent liberador de Zotarolimus Clinical outcomes by geographic region for patients implanted with the zotarolimus-eluting stent

    Directory of Open Access Journals (Sweden)

    Chaim Lotan

    2011-05-01

    Full Text Available FUNDAMENTO: Diferenças entre regiões geográficas em relação à características de pacientes e desfechos, particularmente em síndromes coronarianas agudas, tem sido demonstradas em testes clínicos. Os desfechos clínicos após intervenções coronarianas percutâneas com o stent eluidor de Zotarolimus em uma população real foram analisados com o tempo. OBJETIVO: A influência da localização geográfica sobre os desfechos clínicos com o stent eluidor de Zotarolimus foi avaliada em três regiões: Pacífico Asiático, Europa e América Latina. MÉTODOS: Um total de 8.314 pacientes (6.572 da Europa, 1.522 do Pacífico Asiático e 220 da América Latina foram acompanhados por 1 ano; 2.116 desses (1.613, 316, e 187, respectivamente foram acompanhados por 2 anos. Características dos pacientes e lesões, terapia antiplaquetária dupla e desfechos clínicos foram comparados entre a América Latina e as outras duas regiões. RESULTADOS: Os pacientes da América Latina apresentavam a maior proporção de fatores de risco e infarto do miocárdio prévio. O uso da terapia antiplaquetária dupla declinou rapidamente na América Latina, de 44,9% em 6 meses para 22,5% em 1 ano e 7,8% em 2 anos (Europa: 87,4%, 61,5%, 19,7%; Pacífico Asiático: 82,4%, 67,0%, 45,7%, respectivamente. Não houve diferenças significantes entre a América Latina e a Europa ou Pacífico Asiático para qualquer desfecho em qualquer ponto do tempo. A incidência de trombose de stent provável e definitiva pelo Academic Research Consortium foi baixa (FUNDAMENTO: Las diferencias entre las regiones geográficas en relación con las características de pacientes y desenlaces, sobre todo en los síndromes coronarios agudos se ha demostrado en ensayos clínicos. Los desenlaces clínicos después de las intervenciones coronarias percutáneas con stent liberador de zotarolimus en una población real se analizaron a través del tiempo. Objetivos: La influencia de la ubicaci

  2. Angulated Stents-A Novel Stent Improvisation to Manage Difficult Post-tuberculosis Bronchial Stenosis.

    Science.gov (United States)

    Tay, Chee Kiang; Jeong, Byeong-Ho; Kim, Hojoong

    2017-10-18

    Post-tuberculosis bronchostenosis (PTBS), a complication of endobronchial tuberculosis is currently treated by bronchial stenting. However, in cases of angulated bronchial stenoses, difficulty is often encountered in stent insertion and maintenance, resulting in stent migration, granulation tissue overgrowth, and restenosis. To accommodate the angulated alignment of the stenosis, we devised an "angulated stent"-a novel improvisation of the conventional stent via splicing and suturing to achieve a resultant angulated shape. A retrospective review was undertaken to evaluate the performance of this stent. Among 283 PTBS patients who underwent interventional bronchoscopy at our center from 2004 to 2014, 21 were treated with at least one angulated stent. Clinical outcomes, including the stenting duration were investigated. After a median follow-up of 26 months, stent removal was successful in 7 (33.3%) out of 21 patients. In patients managed with angulated stents, the median duration to stent change or eventual removal was longer than those treated with straight tube stents (392 days vs. 86 days; p < 0.05). Angulated stents are a feasible treatment option in patients with angulated PTBS by reducing complications and prolonging the stent-changing interval.

  3. A comparative evaluation of early stent occlusion among biliary conventional versus wing stents.

    Science.gov (United States)

    Khashab, Mouen A; Hutfless, Susan; Kim, Katherine; Lennon, Anne Marie; Canto, Marcia I; Jagannath, Sanjay B; Okolo, Patrick I; Shin, Eun Ji; Singh, Vikesh K

    2012-06-01

    Conventional plastic stents with a lumen typically have limited patency. The lumenless wing stent was engineered to overcome this problem. The objective of this study was to compare the incidence of early stent occlusion (symptomatic occlusion/cholangitis necessitating re-insertion within 90 days) for wing stents and conventional plastic stents. Patients with biliary pathology treated with plastic biliary stenting during the period 2003-2009 comprised the study cohort. Patients who had at least one biliary wing stent placed comprised the wing stent group, whereas patients who underwent only conventional stent plastic placement comprised the conventional stent group. Patients were stratified by indication: benign biliary strictures (group 1), malignant biliary strictures (group 2), or benign biliary non-stricture pathology (group 3). The association of stent type with the occurrence of primary outcome by indication was analyzed by use of multivariable logistic regression. Three-hundred and forty-six patients underwent 612 ERCP procedures with placement of plastic biliary stent(s). On multivariate analysis, early stent occlusion did not differ between the wing and conventional groups in groups 1, 2, and 3. Among patients who achieved primary outcome in group 2, significantly fewer patients in the wing group had cholangitis (6.7% vs. 39.1%, P = 0.03). Among patients who achieved primary outcome in group 3, significantly fewer patients in the wing group had cholangitis (10% vs. 50%, P = 0.03). Early stent occlusion was similar for wing stents and conventional plastic stents. Wing stents, however, were associated with a lower incidence of cholangitis in patients with malignant biliary obstruction and benign non-stricturing biliary pathology.

  4. Mechanical behavior of peripheral stents and stent-vessel interaction: A computational study

    Science.gov (United States)

    Dottori, Serena; Flamini, Vittoria; Vairo, Giuseppe

    2016-05-01

    In this paper stents employed to treat peripheral artery disease are analyzed through a three-dimensional finite-element approach, based on a large-strain and large-displacement formulation. Aiming to evaluate the influence of some stent design parameters on stent mechanics and on the biomechanical interaction between stent and arterial wall, quasi-static and dynamic numerical analyses are carried out by referring to computational models of commercially and noncommercially available versions of both braided self-expandable stents and balloon-expandable stents. Addressing isolated device models, opening mechanisms and flexibility of both opened and closed stent configurations are numerically experienced. Moreover, stent deployment into a stenotic peripheral artery and possible postdilatation angioplasty (the latter for the self-expandable device only) are simulated by considering different idealized vessel geometries and accounting for the presence of a stenotic plaque. Proposed results highlight important differences in the mechanical response of the two types of stents, as well as a significant influence of the vessel shape on the stress distributions arising upon the artery-plaque system. Finally, computational results are used to assess both the stent mechanical performance and the effectiveness of the stenting treatment, allowing also to identify possible critical conditions affecting the risk of stent fracture, tissue damage, and/or pathological tissue response.

  5. Angiographic CT: in vitro comparison of different carotid artery stents-does stent orientation matter?

    Science.gov (United States)

    Lettau, Michael; Bendszus, Martin; Hähnel, Stefan

    2013-06-01

    Our aim was to evaluate the in vitro visualization of different carotid artery stents on angiographic CT (ACT). Of particular interest was the influence of stent orientation to the angiography system by measurement of artificial lumen narrowing (ALN) caused by the stent material within the stented vessel segment to determine whether ACT can be used to detect restenosis within the stent. ACT appearances of 17 carotid artery stents of different designs and sizes (4.0 to 11.0 mm) were investigated in vitro. Stents were placed in different orientations to the angiography system. Standard algorithm image reconstruction and stent-optimized algorithm image reconstruction was performed. For each stent, ALN was calculated. With standard algorithm image reconstruction, ALN ranged from 19.0 to 43.6 %. With stent-optimized algorithm image reconstruction, ALN was significantly lower and ranged from 8.2 to 18.7 %. Stent struts could be visualized in all stents. Differences in ALN between the different stent orientations to the angiography system were not significant. ACT evaluation of vessel patency after stent placement is possible but is impaired by ALN. Stent orientation of the stents to the angiography system did not significantly influence ALN. Stent-optimized algorithm image reconstruction decreases ALN but further research is required to define the visibility of in-stent stenosis depending on image reconstruction.

  6. Coronary and peripheral stenting in aorto-ostial protruding stents: The balloon assisted access to protruding stent technique.

    Science.gov (United States)

    Helmy, Tarek A; Sanchez, Carlos E; Bailey, Steven R

    2016-03-01

    Treatment of aorto-ostial in-stent restenosis lesions represents a challenge for interventional cardiologists. Excessive protrusion of the stent into the aorta may lead to multiple technical problems, such as difficult catheter reengagement of the vessel ostium or inability to re-wire through the stent lumen in repeat interventions. We describe a balloon assisted access to protruding stent technique in cases where conventional coaxial engagement of an aorto-ostial protruding stent with the guide catheter or passage of the guide wire through the true lumen is not feasible. This technique is applicable both in coronary and peripheral arteries. © 2015 Wiley Periodicals, Inc.

  7. Microvascular stent anastomosis using N-fibroin stents: feasibility, ischemia time, and complications.

    Science.gov (United States)

    Smeets, Ralf; Vorwig, Oliver; Wöltje, Michael; Gaudin, Robert; Luebke, Andreas M; Beck-Broichsitter, Benedicta; Rheinnecker, Michael; Heiland, Max; Grupp, Katharina; Gröbe, Alexander; Hanken, Henning

    2016-05-01

    To evaluate a novel microvascular anastomosis technique using N-fibroin stents. Cylinder stents of 1 mm diameter and 5 mm length were fabricated using N-fibroin from silkworms. In 22 rats, aortas were dissected, and the stent was inserted into the two ends of the aorta and fixed using methylmethacrylate. Stent anastomosis was successful in 21 (96%) rats. The mean ischemia time was 7.4 minutes, significantly shorter than the 15.9 minutes in the control group with conventional sutures (P stent anastomosis cases, and marked host rejection was evident at the stent anastomosis sites. Around the stents, thrombi were frequent (52%). Our study demonstrated the basic feasibility of stent anastomosis using N-fibroin stents and reduced ischemia time. However, thrombus formation, frequent and severe abdominal infections, and heavy host rejection remain critical issues. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. The stenting strategy of drug-eluting stents for coronary artery disease in patients on dialysis

    Directory of Open Access Journals (Sweden)

    Hiroshi Fujita

    2014-12-01

    Full Text Available Background: Reports regarding the relationship between the length and diameter of implanted drug-eluting stents and clinical and angiographic outcomes in dialysis patients are limited. Aim: We investigated the efficiency of drug-eluting stents for coronary artery disease in patients on dialysis from the viewpoint of stent sizing. Methods: Sirolimus-eluting stents were implanted in 88 lesions and bare metal stents were implanted in 43 lesions. We compared stenting strategy, major adverse cardiac events, and angiographic results between sirolimus-eluting stent and bare metal stent groups. Results: Stent diameter was smaller and stent length was longer in the sirolimus-eluting stent group than in the bare metal stent group in our routine practices. There was no significant between-group difference in late diameter loss. Rates of angiographic restenosis and target lesion revascularization were significantly higher in the sirolimus-eluting stent group than in the bare metal stent group. Although stent length was significantly longer and stent diameter was smaller in the sirolimus-eluting stent group, sirolimus-eluting stents did not improve the subsequent clinical and angiographic results compared with bare metal stents in dialysis patients. Conclusion: In dialysis patients, a longer length and/or smaller diameter sirolimus-eluting stent implantation was associated with high rates of restenosis and target lesion revascularization compared with bare metal stents.

  9. Stent-in-Stent Technique for the Treatment of Proximal Bronchial Restenosis after Insertion of Metallic Stents: A Report of Two Cases

    Directory of Open Access Journals (Sweden)

    Benjamin Bondue

    2016-01-01

    Full Text Available Endoscopic treatment of a bronchial restenosis previously treated by insertion of a partially covered self-expandable metallic stent (SEMS can be difficult. Classically, after recanalization of the bronchus, the stent is removed and replaced by a more adapted one. We report on two cases of proximal bronchial restenosis treated by insertion of an additional stent inside the lumen of the previously inserted stent using the stent-in-stent (SIS technique. The indications for the initial stent were malignancy in Patient 1 and posttransplant bronchial stenosis in Patient 2. Restenosis occurred at the proximal end of the stent within months in both cases. Stent removal and insertion of a new stent were considered, but this option was discarded because of an excessive risk of bronchial perforation and preference towards an alternative approach. In both cases, a second customized SEMS was placed using the SIS technique after ablation of the proximal end stenosis of the stent by argon plasma coagulation and/or dilation with a balloon. Recanalization of the bronchus was achieved in both cases without complications. The SIS technique is a valuable alternative to removal of SEMS in case of proximal bronchial restenosis.

  10. Endovascular AAA exclusion: will stents with hooks and barbs prevent stent-graft migration?

    Science.gov (United States)

    Malina, M; Lindblad, B; Ivancev, K; Lindh, M; Malina, J; Brunkwall, J

    1998-11-01

    To investigate if stents with hooks and barbs will improve stent-graft fixation in the abdominal aorta. Sixteen- to 24-mm-diameter Dacron grafts were deployed inside cadaveric aortas. The grafts were anchored by stents as in endovascular abdominal aortic aneurysm repair. One hundred thirty-seven stent-graft deployments were carried out with modified self-expanding Z-stents with (A) no hooks and barbs (n = 75), (B) 4 5-mm-long hooks and barbs (n = 39), (C) 8 10-mm-long, strengthened hooks and barbs (n = 19), or (D) hooks only (n = 4). Increasing longitudinal traction was applied to determine the displacement force needed to extract the stent-grafts. The radial force of the stents was measured and correlated to the displacement force. The median (interquartile range) displacement force needed to extract grafts anchored by stent A was 2.5 N (2.0 to 3.4), stent B 7.8 N (7.4 to 10.8), and stent C 22.5 N (17.1 to 27.9), p barbs added anchoring strength. During traction, the weaker barbs were distorted or caused intimal tears. The stronger barbs engaged the entire aortic wall. The radial force of the stents had no impact on fixation, while aortic calcification and graft oversizing had marginal effects. Stent barbs and hooks increased the fixation of stent-grafts tenfold, while the radial force of stents had no impact. These data may prove important in future endograft development to prevent stent-graft migration after aneurysm exclusion.

  11. Preliminary Report of Carotid Artery Stenting Using a Tapered Stent

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Chang Woo; Kim, Dong Hyun; Hong, Seung; Jeong; Kim, Young Suk; Byun, Joo Nam; Oh, Jae Hee [Dept. of Radiology, Chosun University College of Medicine, Gwangju (Korea, Republic of); Ahn, Seong Hwan [Dept. of Neurology, Chosun University College of Medicine, Gwangju (Korea, Republic of)

    2011-10-15

    To analyze the results of carotid artery stenting using a tapered stent and to evaluate the effectiveness of the tapered stent compared to previously reported studies using non-tapered stents. From October 2008 to August 2010, elective carotid artery stenting using a tapered stent was attempted in 39 lesions from 36 consecutive patients. Post-procedural complications were evaluated by neurologic symptoms and magnetic resonance imaging. Restenosis or occlusion was evaluated by carotid Doppler ultrasound and computerized tomography with angiography. Newly developed neurologic symptoms were evaluated clinically. The self-expandable tapered stent was placed across the carotid artery stenosis. A total stroke was noted in 3 patients, while a major stroke was noted in 1 patient. On diffusion weighted imaging, new lesions were observed in 15 patients, but 13 patients were clinically silent. Follow-up imaging studies were performed in the 13 clinically silent lesions, and no evidence of restenosis or occlusion was found any of the 13 lesions. During clinical follow-up in 34 lesions from 31 patients, there were newly developed neurological symptoms in only 1 patient.

  12. Predictive Factors of In-Stent Restenosis in Renal Artery Stenting: A Retrospective Analysis

    International Nuclear Information System (INIS)

    Vignali, Claudio; Bargellini, Irene; Lazzereschi, Michele; Cioni, Roberto; Petruzzi, Pasquale; Caramella, Davide; Pinto, Stefania; Napoli, Vinicio; Zampa, Virna; Bartolozzi, Carlo

    2005-01-01

    Purpose. To retrospectively evaluate the role of clinical and procedural factors in predicting in-stent restenosis in patients with renovascular disease treated by renal artery stenting. Methods. From 1995 to 2002, 147 patients underwent renal artery stenting for the treatment of significant ostial atherosclerotic stenosis. Patients underwent strict clinical and color-coded duplex ultrasound follow-up. Ninety-nine patients (111 stents), with over 6 months of continuous follow-up (mean 22±12 months, range 6-60 months), were selected and classified according to the presence (group A, 30 patients, 32 lesions) or absence (group B, 69 patients, 79 lesions) of significant in-stent restenosis. A statistical analysis was performed to identify possible preprocedural and procedural predictors of restenosis considering the following data: sex, age, smoking habit, diabetes mellitus, hypertension, serum creatinine, cholesterol and triglyceride levels, renal artery stenosis grade, and stent type, length and diameter. Results. Comparing group A and B patients (χ 2 test), a statistically significant relation was demonstrated between stent diameter and length and restenosis: the risk of in-stent restenosis decreased when the stent was ≥6 mm in diameter and between 15 and 20 mm in length. This finding was confirmed by multiple logistic regression analysis. Stent diameter and length were proved to be significantly related to in-stent restenosis also when evaluating only patients treated by Palmaz stent (71 stents). Conclusion. Although it is based on a retrospective analysis, the present study confirms the importance of correct stent selection in increasing long-term patency, using stents of at least 6 mm in diameter and with a length of approximately 15-20 mm

  13. Tratamento de uma coorte de pacientes com infarto agudo do miocárdio com supradesnivelamento do segmento ST Tratamiento de una cohorte de pacientes con infarto agudo de miocardio con supradesnivel del segmento ST Treatment of a cohort of patients with acute myocardial infarction and ST-segment elevation

    Directory of Open Access Journals (Sweden)

    Jamil da Silva Soares

    2009-06-01

    Full Text Available FUNDAMENTO: Trombólise e angioplastia transluminal coronariana (ATC primária são técnicas bem estabelecidas, mas grande parte dos pacientes com infarto agudo do miocárdio com supradesnivelamento do segmento ST (IAM com SST não as recebem quando do atendimento hospitalar. OBJETIVO: Descrever tratamentos inicial e final e desfechos de uma coorte com IAM com SST. MÉTODOS: Analisados, da internação até a alta, 158 pacientes com IAM com SST, de uma população total de 351 pacientes internados com (SCA nos hospitais de Campos dos Goytacazes, entre 2004 e 2006. RESULTADOS: Dos 158 pacientes com IAM com SST, 67,7% chegaram ao hospital nos primeiros 180 minutos, 81,3% em 360 minutos e 8,4% após doze horas. Realizados 148 estudos cinecoronariográficos (93,7%. Observadas lesões de mais de 70% em 266 territórios arteriais. Tratamento inicial foi ATC em 41(26%, trombolíticos em 50 (32%, com 80% de sucesso. Tratamento clínico em 67 (42%. Cerca de 35% dos pacientes deveriam ser trombolizados mas não o foram. No tratamento final foram 93 ATCs, 89 delas com sucesso angiográfico (95,7, sangramento 2 (2,2, oclusão subaguda 2 (2,2%, dissecção tronco 1 (1,1, pseudo aneurisma 1 (1,1. Nenhum óbito durante angioplastia; na evolução, houve dois óbitos (2,1%. Doze pacientes submetidos a cirurgia de revascularização miocárdica (CRM. Tratamento clínico 53 (33%, com 11 óbitos (20,7%. Letalidade global 9,5%, consideradas as três formas de tratamento. CONCLUSÃO: Pacientes atendidos em tempo adequado para reperfusão, porém 1/3 deles não recebeu o procedimento. Tratamento predominante foi ATC, com baixa morbidade. Dois óbitos na evolução. Baixa letalidade global.FUNDAMENTO: La trombólisis y la angioplastia transluminal coronaria (ATC primaria son técnicas bien establecidas, sin embargo gran parte de los pacientes con infarto agudo de miocardio con supradesnivel del segmento ST (IAM con SST no las reciben cuando de la atenci

  14. Intravascular stent graft with polyurethane and metallic stent: experimental study

    International Nuclear Information System (INIS)

    Do, Young Soo; Lee, Won Jae; Kim, Boo Kyung Han; Park, Jae Hyung; Lee, Hak Jong; Lee, Sang Hyun; Kim, Sung Hyun; Kim, Jong Won; Ha, Jongwon

    1997-01-01

    To evaluate the usefulness of a new model of the stent graft, and of tissue response related to placement of the stent graft. The stent graft was constructed from polyurethane (Pellethane) graft and Hanaro stent(12mm in diameter, 45mm in length, 10 bends). A stent grafts was inserted into the lower thoracic aorta in each of six adult mongrel dogs(body weight, 12-16kg). At one, two, four, and six months, follow-up studies of angiography and spiral CT angiography were preformed to evaluate wascular patency, vascular stenosis, and thrombus formation. Two dogs were sacrificed at 1month, 2months, and 6months after insertion of the stent graft and macroscopic, light microscopic, and scanning electron microscopic examinations of the aortic segment including the stent graft were performed to evaluate intimal hyperplasia, endothelial growth to the graft, and thrombus formation. During follow-up at one, two, four, and six months, angiography or spiral CT angiography showed 20-100% luminal stenosis or occlusion of the lower thoracic aorta by the thrombus and perigraft leaks in three dogs(50%), and collateral vessels caused by occlusion of the aorta in two (33.3%). On gross examination, there were thrombi of 1-5mm thickness at the graft portions in all dogs, and this thickness gradually increased. The mean thickness of intimal hyperplasia at the stent portion gradually increased from 120μm to 227μm and the mean thickness of intimal hyperplasia at the graft portion from 93μm to 914μm. This thickness was greater at the graft portion than at the stent portion. Scanning electron microscopy showed elliptical endothelial lining on the neointimal surfaces at each end of the graft. Thrombi caused stenosis or occlusion of the stent graft. In order for such a graft to be ideal, further study is needed

  15. Stent Coating Integrity of Durable and Biodegradable Coated Drug Eluting Stents.

    Science.gov (United States)

    Yazdani, Saami K; Sheehy, Alexander; Pacetti, Stephen; Rittlemeyer, Brandon; Kolodgie, Frank D; Virmani, Renu

    2016-10-01

    Coatings consisting of a polymer and drug are widely used in drug-eluting stents (DES) and are essential in providing programmable drug release kinetics. Among other factors, stent coating technologies can influence blood compatibility, affect acute and sub-acute healing, and potentially trigger a chronic inflammatory response. The aim of this study was to investigate the short-term (7 and 28 days) and long-term (90 and 180 days) coating integrity of the Xience Prime Everolimus-Eluting Stent (EES), Resolute Zotarolimus-Eluting Stent (ZES), Taxus Paclitaxel-Eluting Stent (PES), and Nobori Biolimus A9-Eluting Stent (BES) in a rabbit ilio-femoral stent model. Stented arteries (n = 48) were harvested and the tissue surrounding the implanted stents digested away with an enzymatic solution. Results demonstrated that the majority of struts of EES were without any coating defects with a few struts showing minor defects. Similarly, for the ZES, most of the struts were without coating defects at all time points except at 180 days. The majority of PES demonstrated mostly webbing and uneven coating. In the BES group, the majority of strut coating showed polymer cracking. Overall, the EES and ZES had fewer coating defects than the PES and BES. Coating defects, however increase over time for the ZES, whereas the percent of coating irregularities remained constant for the EES. These results provide, for the first time, a comparison of the long-term durability of these drug-eluting stent coatings in vivo. © 2016, Wiley Periodicals, Inc.

  16. Mechanisms and Patterns of Intravascular Ultrasound In-Stent Restenosis Among Bare Metal Stents and First- and Second-Generation Drug-Eluting Stents.

    Science.gov (United States)

    Goto, Kosaku; Zhao, Zhijing; Matsumura, Mitsuaki; Dohi, Tomotaka; Kobayashi, Nobuaki; Kirtane, Ajay J; Rabbani, LeRoy E; Collins, Michael B; Parikh, Manish A; Kodali, Susheel K; Leon, Martin B; Moses, Jeffrey W; Mintz, Gary S; Maehara, Akiko

    2015-11-01

    The most common causes of in-stent restenosis (ISR) are intimal hyperplasia and stent under expansion. The purpose of this study was to use intravascular ultrasound (IVUS) to compare the ISR mechanisms of bare metal stents (BMS), first-generation drug-eluting stents (DES), and second-generation DES. There were 298 ISR lesions including 52 BMS, 73 sirolimus-eluting stents, 52 paclitaxel-eluting stents, 16 zotarolimus-eluting stents, and 105 everolimus-eluting stent. Mean patient age was 66.6 ± 1.1 years, 74.2% were men, and 48.3% had diabetes mellitus. BMS restenosis presented later (70.0 ± 66.7 months) with more intimal hyperplasia compared with DES (BMS 58.6 ± 15.5%, first-generation DES 52.6 ± 20.9%, second-generation DES 48.2 ± 22.2%, p = 0.02). Although reference lumen areas were similar in BMS and first- and second-generation DES, restenotic DES were longer (BMS 21.8 ± 13.5 mm, first-generation DES 29.4 ± 16.1 mm, second-generation DES 32.1 ± 18.7 mm, p = 0.003), and stent areas were smaller (BMS 7.2 ± 2.4 mm(2), first-generation DES 6.1 ± 2.1 mm(2), second-generation DES 5.7 ± 2.0 mm(2), p Stent fracture was seen only in DES (first-generation DES 7 [5.0%], second-generation DES 8 [7.4%], p = 0.13). In conclusion, restenotic first- and second-generation DES were characterized by less neointimal hyperplasia, smaller stent areas, longer stent lengths, and more stent fractures than restenotic BMS. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. 4D phase contrast flow imaging for in-stent flow visualization and assessment of stent patency in peripheral vascular stents--a phantom study.

    Science.gov (United States)

    Bunck, Alexander C; Jüttner, Alena; Kröger, Jan Robert; Burg, Matthias C; Kugel, Harald; Niederstadt, Thomas; Tiemann, Klaus; Schnackenburg, Bernhard; Crelier, Gerard R; Heindel, Walter; Maintz, David

    2012-09-01

    4D phase contrast flow imaging is increasingly used to study the hemodynamics in various vascular territories and pathologies. The aim of this study was to assess the feasibility and validity of MRI based 4D phase contrast flow imaging for the evaluation of in-stent blood flow in 17 commonly used peripheral stents. 17 different peripheral stents were implanted into a MR compatible flow phantom. In-stent visibility, maximal velocity and flow visualization were assessed and estimates of in-stent patency obtained from 4D phase contrast flow data sets were compared to a conventional 3D contrast-enhanced magnetic resonance angiography (CE-MRA) as well as 2D PC flow measurements. In all but 3 of the tested stents time-resolved 3D particle traces could be visualized inside the stent lumen. Quality of 4D flow visualization and CE-MRA images depended on stent type and stent orientation relative to the magnetic field. Compared to the visible lumen area determined by 3D CE-MRA, estimates of lumen patency derived from 4D flow measurements were significantly higher and less dependent on stent type. A higher number of stents could be assessed for in-stent patency by 4D phase contrast flow imaging (n=14) than by 2D phase contrast flow imaging (n=10). 4D phase contrast flow imaging in peripheral vascular stents is feasible and appears advantageous over conventional 3D contrast-enhanced MR angiography and 2D phase contrast flow imaging. It allows for in-stent flow visualization and flow quantification with varying quality depending on stent type. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  18. Causes and prevention of in-stent restenosis of vertebral artery origin after stenting

    International Nuclear Information System (INIS)

    Zhao Huipin; Li Shenmao; Zhang Guangping

    2010-01-01

    Vertebral artery stenosis is an important cause of posterior circulation stroke. Vertebral artery stenosis most commonly occurs at its origin site. In recent years, balloon angioplasty and stent implantation have been widely employed in the treatment of vertebral artery origin stenosis. However, the long term outcome of stent implantation is affected by in-stent restenosis. Multiple contributory factors have been identified, but clear understanding of the overall underlying mechanism remains an enigma. With the development of pathophysiology, prevention and treatment methods of in-stent restenosis have been improved. In recent years, drug-eluting stents, radioactive stents and magnetic stents have been widely applied. To some extent, these stents and drug therapy can solve the problem of restenosis. This article aims to review the clinical application and the up-to-date research progresses in preventing and managing vertebral artery origin restenosis. (authors)

  19. Outcomes of the single-stent versus kissing-stents technique in asymmetric complex aortoiliac bifurcation lesions.

    Science.gov (United States)

    Suh, Yongsung; Ko, Young-Guk; Shin, Dong-Ho; Kim, Jung-Sun; Kim, Byeong-Keuk; Choi, Donghoon; Hong, Myeong-Ki; Jang, Yangsoo

    2015-07-01

    This study investigated the outcomes of single-stent vs kissing-stents techniques in asymmetric complex aortoiliac bifurcation (ACAB) lesions. We retrospectively investigated 80 consecutive patients (69 males, 66.6 ± 8.7 years) treated with a single stent and 30 patients (26 males, 67.1 ± 7.7 years) treated with kissing stents for ACAB between January 2005 and December 2012 from a single-center cohort. A ACAB lesion was defined as a symptomatic unilateral common iliac artery stenosis (>50%) combined with intermediate stenosis (30%-50%) in the contralateral common iliac artery ostium. The primary end point was the primary patency of the ACAB. The baseline clinical characteristics did not differ significantly between the single-stent and the kissing-stents group. Technical success was achieved in all patients. The single-stent group required fewer stents (1.3 ± 0.5 vs 2.3 ± 0.8; P stent group (3%) required bailout kissing stents because of plaque shift to the contralateral side. The major complication rates were 8% in single-stent vs 13% in the kissing-stent group, which was similar (P = .399). At 3 years, the single-stent and kissing-stents group had similar rates of primary patency (89% vs 87%; P = .916) and target lesion revascularization-free survival (93% vs 87%; P = .462). The single-stent technique in ACAB was safe and showed midterm outcomes comparable with those of kissing stents. Considering the benefits, such as fewer stents, less bilateral femoral access, and the availability of contralateral access for future intervention, the single-stent technique may be an advantageous treatment option in ACAB. Copyright © 2015 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

  20. Plastic Biliary Stent Migration During Multiple Stents Placement and Successful Endoscopic Removal Using Intra-Stent Balloon Inflation Technique: A Case Report and Literature Review.

    Science.gov (United States)

    Calcara, Calcedonio; Broglia, Laura; Comi, Giovanni; Balzarini, Marco

    2016-02-05

    Late migration of a plastic biliary stent after endoscopic placement is a well known complication, but there is little information regarding migration of a plastic stent during multiple stents placement. A white man was hospitalized for severe jaundice due to neoplastic hilar stenosis. Surgical eligibility appeared unclear on admission and endoscopy was carried out, but the first stent migrated proximally at the time of second stent insertion. After failed attempts with various devices, the migrated stent was removed successfully through cannulation with a dilation balloon. The migration of a plastic biliary stent during multiple stents placement is a possible complication. In this context, extraction can be very complicated. In our patient, cannulation of a stent with a dilation balloon was the only effective method.

  1. Genous endothelial progenitor cell-capturing stent system: a novel stent technology

    NARCIS (Netherlands)

    Klomp, Margo; Beijk, Marcel A. M.; de Winter, Robbert J.

    2009-01-01

    Drug-eluting stents have been demonstrated to significantly reduce clinical and angiographic restenosis in patients with coronary artery disease compared with bare-metal stents. Intuitively, however, a prohealing approach for the prevention of in-stent restenosis by promoting accelerated

  2. Prospective Multicenter Study on the Challenges Inherent to Using Large Cell-Type Stents for Bilateral Stent-in-Stent Placement in Patients with Inoperable Malignant Hilar Biliary Obstruction.

    Science.gov (United States)

    Yang, Min Jae; Kim, Jin Hong; Hwang, Jae Chul; Yoo, Byung Moo; Lee, Sang Hyub; Ryu, Ji Kon; Kim, Yong-Tae; Woo, Sang Myung; Lee, Woo Jin; Jeong, Seok; Lee, Don Haeng

    2018-06-22

    Although endoscopic bilateral stent-in-stent placement is challenging, many recent studies have reported promising outcomes regarding technical success and endoscopic reintervention. This study aimed to evaluate the technical feasibility of stent-in-stent placement using large cell-type stents in patients with inoperable malignant hilar biliary obstruction. Forty-three patients with inoperable malignant hilar biliary obstruction from four academic centers were prospectively enrolled from March 2013 to June 2015. Bilateral stent-in-stent placement using two large cell-type stents was successfully performed in 88.4% of the patients (38/43). In four of the five cases with technical failure, the delivery sheath of the second stent became caught in the hook-cross-type vertex of the large cell of the first stent, and subsequent attempts to pass a guidewire and stent assembly through the mesh failed. Functional success was achieved in all cases with technical success. Stent occlusion occurred in 63.2% of patients (24/38), with a median patient survival of 300 days. The median stent patency was 198 days. The stent patency rate was 82.9%, 63.1%, and 32.1% at 3, 6, and 12 months, respectively. Endoscopic re-intervention was performed in 14 patients, whereas 10 underwent percutaneous drainage. Large cell-type stents for endoscopic bilateral stent-in-stent placement showed acceptable functional success and stent patency when technically successful. However, the technical difficulty associated with the entanglement of the second stent delivery sheath in the hook-cross-type vertex of the first stent may preclude large cell-type stents from being considered as a dedicated standard tool for stent-in-stent placement.

  3. Delayed cerebral infarction due to stent folding deformation following carotid artery stenting

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Kwon Duk; Lee, Kyung Yul; Suh, Sang Hyun [Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul (Korea, Republic of); Kim, Byung Moon [Dept. of Radiology, Severance Hospital, Yonsei University College of Medicine, Seoul (Korea, Republic of)

    2014-12-15

    We report a case of delayed cerebral infarction due to stent longitudinal folding deformation following carotid artery stenting using a self-expandable stent with an open-cell design. The stented segment of the left common carotid artery was divided into two different lumens by this folding deformation, and the separated lumens became restricted with in-stent thrombosis. Although no established method of managing this rare complication exists, a conservative approach was taken with administration of anticoagulant and dual antiplatelet therapy. No neurological symptoms were observed during several months of clinical follow-up after discharge.

  4. MR Angiography of Peripheral Arterial Stents: In Vitro Evaluation of 22 Different Stent Types

    Directory of Open Access Journals (Sweden)

    Matthias C. Burg

    2011-01-01

    Full Text Available Purpose. To evaluate stent lumen visibility of a large sample of different peripheral arterial (iliac, renal, carotid stents using magnetic resonance angiography in vitro. Materials and Methods. 21 different stents and one stentgraft (10 nitinol, 7 316L, 2 tantalum, 1 cobalt superalloy, 1 PET + cobalt superalloy, and 1 platinum alloy were examined in a vessel phantom (vessel diameters ranging from 5 to 13 mm filled with a solution of Gd-DTPA. Stents were imaged at 1.5 Tesla using a T1-weighted 3D spoiled gradient-echo sequence. Image analysis was performed measuring three categories: Signal intensity in the stent lumen, lumen visibility of the stented lumen, and homogeneity of the stented lumen. The results were classified using a 3-point scale (good, intermediate, and poor results. Results. 7 stents showed good MR lumen visibility (4x nitinol, 2x tantalum, and 1x cobalt superalloy. 9 stents showed intermediate results (5x nitinol, 2x 316L, 1x PET + cobalt superalloy, and 1x platinum alloy and 6 stents showed poor results (1x nitinol, and 5x 316L. Conclusion. Stent lumen visibility varies depending on the stent material and type. Some products show good lumen visibility which may allow the detection of stenoses inside the lumen, while other products cause artifacts which prevent reliable evaluation of the stent lumen with this technique.

  5. Stent insertion in patients with malignant biliary obstruction: problems of the Hanaro stent

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Jae Hyun; Seong, Chang Kyu; Shin, Tae Beom; Kim, Yong Joo [School of Medicine, Kyungpook National Univ., Daegu (Korea, Republic of); Jung, Gyoo Sik [School of Medicine, Kosin National Univ., Pusan (Korea, Republic of); Park, Byeung Ho [School of Medicine, Donga National Univ., Pusan (Korea, Republic of)

    2002-07-01

    To investigate the problems of the Hanaro stent (Solco Intermed, Seoul, Korea) when used in the palliative treatment of patients with inoperable malignant biliary obstruction. Between January 2000 and May 2001, the treatment of 46 patients with malignant biliary obstruction involved percutaneous placement of the Hanaro stent. Five patients encountered problems during removal of the stent's introduction system. The causes of obstruction were pancreatic carcinoma (n=2), cholangiocarcinoma (n=2), and gastric carcinoma with biliary invasion (n=1). In one patient, percutaneous transhepatic cholangiography and stent insertion were performed as a one-step procedure, while the others underwent conventional percutaneous transhepatic biliary drainage for at least two days prior to stent insertion. A self-expandable Hanaro stent, 8-10 mm in deameter and 50-100 mm in lengh, and made from a strand of nitinol wire, was used in all cases. Among the five patients who encountered problems, breakage of the olive tip occourred in three, upward displacement of the stent in two, and improper expansion of the distal portion of the stent, unrelated with the obstruction site, in one. The broken olive tip was pushed to the duodenum in two cases and to the peripheral intrahepatic duct in one. Where the stent migrated during withdrawal of its introduction system, an additional stent was inserted. In one case, the migrated stent was positioned near the liver capsule and the drainage catheter could not be removed. Although the number of patients in this study was limited, some difficulties were encountered in withdrawing the stent's introduction system. To prevent the occurrence of this unusual complication, the stent should be appropriately expansile, and shape in the olive tip should be considered.

  6. Risk Factors and Clinical Evaluation of Superficial Femoral Artery Stent Fracture: Prote'ge'GPS Stent

    International Nuclear Information System (INIS)

    Lee, Da Un; Kim, Jae Kyu; Jung, Hye Doo; Huh, Tae Wook; Yim, Nam Yeol; Oh, Hyun jun; Choi, Soo Jin Na; Chang, Nam Kyu

    2010-01-01

    To evaluate the occurrence of superficial femoral artery stent fractures, the risk factors of stent fracture, and the relationship between fractures and clinical findings. Of the 38 patients who underwent treatment with Prote'ge'GPS stenting due to arterial occlusions on the superficial femoral artery, 17 also underwent a clinical analysis. Forty-three stents were inserted in the 17 superficial femoral arteries, ranging between 15 and 50 cm in length, with a mean treated length of 26.4 cm (15-50 cm). A fracture was evaluated by taking a PA and lateral simple radiography, as well as a follow-up evaluation accompanied with a CT angiography, DSA, and a color Doppler sonography. The examination involved the assessment of the difference between bone fractures due to length, placement, and frequency. Fractures occurred in 13 of 43 stents (30.2%). A total of 10 (71.4%) occurred in the upper third, compared to 4 (28.6%) in the lower third of the superficial femoral artery. In addition, 10 stents (71.4%) had a single strut fracture, whereas 4 (28.6%) had multiple strut fractures. A stent fracture occurred more frequently when the stents and lesions were longer (p=0.021, 0.012) and the stents were inserted near the joint. However, there was no significant relationship between stent numbers and the fractures (p=0.126). When the stents were inserted along the popliteal artery, a stent fracture occurred more frequently in the lower third of the artery. The stent fractures did not significantly influence the patency rate of the stented artery (p=0.44) Prote'ge'GPS stents in the superficial femoral artery revealed a considerable number of fractures and the fracture frequency showed a significant relationship with the length of stents and lesions. The closer stent insertion was to the joints, the more frequently fractures occurred. There were no evident significant relationships between the presence of stent fractures and the patency of the stented arteries

  7. 4D phase contrast flow imaging for in-stent flow visualization and assessment of stent patency in peripheral vascular stents – A phantom study

    International Nuclear Information System (INIS)

    Bunck, Alexander C.; Jüttner, Alena; Kröger, Jan Robert; Burg, Matthias C.; Kugel, Harald; Niederstadt, Thomas; Tiemann, Klaus; Schnackenburg, Bernhard; Crelier, Gerard R.

    2012-01-01

    Purpose: 4D phase contrast flow imaging is increasingly used to study the hemodynamics in various vascular territories and pathologies. The aim of this study was to assess the feasibility and validity of MRI based 4D phase contrast flow imaging for the evaluation of in-stent blood flow in 17 commonly used peripheral stents. Materials and methods: 17 different peripheral stents were implanted into a MR compatible flow phantom. In-stent visibility, maximal velocity and flow visualization were assessed and estimates of in-stent patency obtained from 4D phase contrast flow data sets were compared to a conventional 3D contrast-enhanced magnetic resonance angiography (CE-MRA) as well as 2D PC flow measurements. Results: In all but 3 of the tested stents time-resolved 3D particle traces could be visualized inside the stent lumen. Quality of 4D flow visualization and CE-MRA images depended on stent type and stent orientation relative to the magnetic field. Compared to the visible lumen area determined by 3D CE-MRA, estimates of lumen patency derived from 4D flow measurements were significantly higher and less dependent on stent type. A higher number of stents could be assessed for in-stent patency by 4D phase contrast flow imaging (n = 14) than by 2D phase contrast flow imaging (n = 10). Conclusions: 4D phase contrast flow imaging in peripheral vascular stents is feasible and appears advantageous over conventional 3D contrast-enhanced MR angiography and 2D phase contrast flow imaging. It allows for in-stent flow visualization and flow quantification with varying quality depending on stent type

  8. Partially Covered Metal Stents May Not Prolong Stent Patency Compared to Uncovered Stents in Unresectable Malignant Distal Biliary Obstruction

    Science.gov (United States)

    Kim, Jae Yun; Ko, Gyu Bong; Lee, Tae Hoon; Park, Sang-Heum; Lee, Yun Nah; Cho, Young Sin; Jung, Yunho; Chung, Il-Kwun; Choi, Hyun Jong; Cha, Sang-Woo; Moon, Jong Ho; Cho, Young Deok; Kim, Sun-Joo

    2017-01-01

    Background/Aims Controversy still exists regarding the benefits of covered self-expandable metal stents (SEMSs) compared to uncovered SEMSs. We aimed to compare the patency and stent-related adverse events of partially covered SEMSs (PC-SEMSs) and uncovered SEMSs in unresectable malignant distal biliary obstruction. Methods A total of 134 patients who received a PC-SEMS or uncovered SEMS for palliation of unresectable malignant distal biliary obstruction were reviewed retrospectively. The main outcome measures were stent patency, stent-related adverse events, and overall survival. Results The median stent patency was 118 days (range, 3 to 802 days) with PC-SEMSs and 105 days (range, 2 to 485 days) with uncovered SEMSs (p=0.718). The overall endoscopic revision rate due to stent dysfunction was 36.6% (26/71) with PC-SEMSs and 36.5% (23/63) with uncovered SEMSs (p=0.589). Tumor ingrowth was more frequent with uncovered SEMSs (4.2% vs 19.1%, p=0.013), but migration was more frequent with PC-SEMSs (11.2% vs 1.5%, p=0.04). The incidence of stent-related adverse events was 2.8% (2/71) with PC-SEMSs and 9.5% (6/63) with uncovered SEMSs (p=0.224). The median overall survival was 166 days with PC-SEMSs and 168 days with uncovered SEMSs (p=0.189). Conclusions Compared to uncovered SEMSs, PC-SEMSs did not prolong stent patency in unresectable malignant distal biliary obstruction. Stent migration was more frequent with PC-SEMSs. However, tumor ingrowth was less frequent with PC-SEMSs compared to uncovered SEMSs. PMID:28208003

  9. Efetividade de um protocolo assistencial para redução do tempo porta-balão da angioplastia primária

    Directory of Open Access Journals (Sweden)

    Luis Cláudio Lemos Correia

    2013-07-01

    Full Text Available FUNDAMENTO: Tempo porta-balão adequado (< 120 minutos é a condição necessária para que a eficácia da angioplastia primária no infarto se traduza em efetividade. OBJETIVO: Descrever a efetividade de um protocolo de qualidade assistencial para redução do tempo porta-balão. MÉTODOS: Entre maio de 2010 e agosto de 2012, foram analisados todos os indivíduos que realizaram angioplastia primária em nosso hospital. O momento porta foi registrado eletronicamente, pela retirada de senha para atendimento na emergência, o que antecede o preenchimento da ficha e a triagem. O momento balão foi definido como o início da abertura da artéria (passagem do primeiro dispositivo. Os primeiros 5 meses de monitoramento corresponderam ao período pré-implementação do protocolo. O protocolo se constituiu de definição do fluxo de ações, desde a chegada do paciente ao hospital, a sensibilização da equipe quanto à priorização do tempo e a apresentação periódica de parecer dos resultados e de possíveis inadequações. RESULTADOS: Foram avaliados 50 indivíduos, divididos em cinco grupos de 10 pacientes sequenciais (um grupo pré e quatro grupos pós-protocolo. O tempo porta-balão referente aos 10 casos registrados antes da implementação do protocolo foi de 200 ± 77 minutos. Após a implementação do protocolo, houve progressiva melhora do tempo porta-balão, para 142 ± 78 minutos nos 10 primeiros pacientes, seguida de 150±50 minutos, 131±37 minutos e, finalmente, 116 ± 29 minutos no três grupos sequenciais de 10 pacientes, respectivamente. Regressão linear entre pacientes sequenciais e tempo porta-balão (r = - 0,41 evidenciou coeficiente de regressão de - 1,74 minutos. CONCLUSÃO: A implementação do protocolo se mostrou efetiva na redução do tempo porta-balão.

  10. Comparison of self-expandable and balloon-expanding stents for hybrid ductal stenting in hypoplastic left heart complex.

    Science.gov (United States)

    Goreczny, Sebastian; Qureshi, Shakeel A; Rosenthal, Eric; Krasemann, Thomas; Nassar, Mohamed S; Anderson, David R; Morgan, Gareth J

    2017-07-01

    We aimed to compare the procedural and mid-term performance of a specifically designed self-expanding stent with balloon-expandable stents in patients undergoing hybrid palliation for hypoplastic left heart syndrome and its variants. The lack of specifically designed stents has led to off-label use of coronary, biliary, or peripheral stents in the neonatal ductus arteriosus. Recently, a self-expanding stent, specifically designed for use in hypoplastic left heart syndrome, has become available. We carried out a retrospective cohort comparison of 69 neonates who underwent hybrid ductal stenting with balloon-expandable and self-expanding stents from December, 2005 to July, 2014. In total, 43 balloon-expandable stents were implanted in 41 neonates and more recently 47 self-expanding stents in 28 neonates. In the balloon-expandable stents group, stent-related complications occurred in nine patients (22%), compared with one patient in the self-expanding stent group (4%). During follow-up, percutaneous re-intervention related to the ductal stent was performed in five patients (17%) in the balloon-expandable stent group and seven patients (28%) in self-expanding stents group. Hybrid ductal stenting with self-expanding stents produced favourable results when compared with the results obtained with balloon-expandable stents. Immediate additional interventions and follow-up re-interventions were similar in both groups with complications more common in those with balloon-expandable stents.

  11. Future developments in biliary stenting

    Directory of Open Access Journals (Sweden)

    Hair CD

    2013-06-01

    Full Text Available Clark D Hair,1 Divyesh V Sejpal21Department of Medicine, Section of Gastroenterology and Hepatology, Baylor College of Medicine, Houston, TX, USA; 2Department of Medicine, Section of Gastroenterology, Hofstra North Shore-LIJ School of Medicine, North Shore University Hospital, Manhasset, NY, USAAbstract: Biliary stenting has evolved dramatically over the past 30 years. Advancements in stent design have led to prolonged patency and improved efficacy. However, biliary stenting is still affected by occlusion, migration, anatomical difficulties, and the need for repeat procedures. Multiple novel plastic biliary stent designs have recently been introduced with the primary goals of reduced migration and improved ease of placement. Self-expandable bioabsorbable stents are currently being investigated in animal models. Although not US Food and Drug Administration approved for benign disease, fully covered self-expandable metal stents are increasingly being used in a variety of benign biliary conditions. In malignant disease, developments are being made to improve ease of placement and stent patency for both hilar and distal biliary strictures. The purpose of this review is to describe recent developments and future directions of biliary stenting.Keywords: plastic stents, self-expandable metal stents, drug eluting stents, bioabsorbable stents, malignant biliary strictures, benign biliary strictures

  12. Targeting In-Stent-Stenosis with RGD- and CXCL1-Coated Mini-Stents in Mice.

    Science.gov (United States)

    Simsekyilmaz, Sakine; Liehn, Elisa A; Weinandy, Stefan; Schreiber, Fabian; Megens, Remco T A; Theelen, Wendy; Smeets, Ralf; Jockenhövel, Stefan; Gries, Thomas; Möller, Martin; Klee, Doris; Weber, Christian; Zernecke, Alma

    2016-01-01

    Atherosclerotic lesions that critically narrow the artery can necessitate an angioplasty and stent implantation. Long-term therapeutic effects, however, are limited by excessive arterial remodeling. We here employed a miniaturized nitinol-stent coated with star-shaped polyethylenglycole (star-PEG), and evaluated its bio-functionalization with RGD and CXCL1 for improving in-stent stenosis after implantation into carotid arteries of mice. Nitinol foils or stents (bare metal) were coated with star-PEG, and bio-functionalized with RGD, or RGD/CXCL1. Cell adhesion to star-PEG-coated nitinol foils was unaltered or reduced, whereas bio-functionalization with RGD but foremost RGD/CXCL1 increased adhesion of early angiogenic outgrowth cells (EOCs) and endothelial cells but not smooth muscle cells when compared with bare metal foils. Stimulation of cells with RGD/CXCL1 furthermore increased the proliferation of EOCs. In vivo, bio-functionalization with RGD/CXCL1 significantly reduced neointima formation and thrombus formation, and increased re-endothelialization in apoE-/- carotid arteries compared with bare-metal nitinol stents, star-PEG-coated stents, and stents bio-functionalized with RGD only. Bio-functionalization of star-PEG-coated nitinol-stents with RGD/CXCL1 reduced in-stent neointima formation. By supporting the adhesion and proliferation of endothelial progenitor cells, RGD/CXCL1 coating of stents may help to accelerate endothelial repair after stent implantation, and thus may harbor the potential to limit the complication of in-stent restenosis in clinical approaches.

  13. Self-expandable metallic stents vs. plastic stents for endoscopic biliary drainage in hepatocellular carcinoma.

    Science.gov (United States)

    Chung, Kwang Hyun; Lee, Sang Hyub; Park, Jin Myung; Lee, Jae Min; Ahn, Dong-Won; Ryu, Ji Kon; Kim, Yong-Tae

    2015-06-01

    The patency of self-expandable metallic stents (SEMS) is known to be better than plastic stents in the palliation of malignant biliary obstruction. However, data are scarce for obstructive jaundice caused by hepatocellular carcinoma (HCC). This study aimed to compare SEMSs and plastic stents for the palliation of obstructive jaundice in unresectable HCC. A total of 96 patients who underwent endoscopic retrograde biliary drainage with SEMSs or plastic stents were included in this retrospective analysis. The rate of successful biliary drainage, adverse events, stent patency duration, and patient survival were compared between the SEMS (n = 36) and plastic stent (n = 60) groups. The rate of successful biliary drainage was similar between the SEMS and plastic stent groups (25/36 [69.4 %] vs. 39/60 [65.0 %]; P = 0.655). Adverse events occurred in 6 patients (16.7 %) in the SEMS group and 13 patients (21.7 %) in the plastic stent group (P = 0.552). The median patency duration was also similar between the two groups (60 vs. 68 days; P = 0.396). The median patient survival was longer in the plastic stent group than in the SEMS group (123 vs. 48 days; P = 0.005). SEMSs were not superior to plastic stents for the palliation of malignant biliary obstruction in HCC with regard to successful drainage, stent patency, and adverse events. Patient survival was better in the plastic stent group. Given the lower cost, plastic stents could be a favorable option for malignant biliary obstruction caused by HCC. © Georg Thieme Verlag KG Stuttgart · New York.

  14. Mechanical properties of various z-stent designs: an endovascular stent-grafting perspective.

    Science.gov (United States)

    Bashar, Abul Hasan Muhammad; Kazui, Teruhisa; Washiyama, Naoki; Terada, Hitoshi; Yamashita, Katsushi; Haque, Mohammad E

    2003-08-01

    To comparatively assess the mechani-cal behavior of various clinically relevant Z-stent designs. A total of 16 Z-stents of original, biliary, spiral, and double-skirted designs (n=4 for each) were constructed using similar specifications for all. Stents were then evaluated for stiffness, snap opening force (SOF), flexibility, and displacement force using a novel tensiometer. Differences among the stents were determined using statistical methods. Stents explanted from dog aorta after a mean follow-up of 13 months were examined under a scanning electron microscope for surface defects. Forces required for about 50% reduction in diameter were 1.88 +/- 0.16 N, 3.81 +/- 0.21 N, 2.76 +/- 0.22 N, and 3.35 +/- 0.19 N for original, biliary, spiral, and skirted designs, respectively. Differences among the four designs were statistically significant at almost all points of measurement (P designs showed higher SOF values in the early measurements. Stents explanted from dog aorta after a mean duration of 13 months showed no obvious corrosion or breakage in the wire struts. Significant differences exist among the various Z-stent designs in terms of their mechanical properties. Understanding them should help to select the appropriate stent for a given lesion. 316L stainless steel shows a favorable long-term tissue interaction.

  15. Nasolacrimal Stenting: Toward Improving Outcomes with a Simple Modification of the Song Stent

    International Nuclear Information System (INIS)

    Lanciego, Carlos; Miguel, Silvia De; Padilla, Manuel; Perea, Miguel; Rodriguez-Merlo, Rufo; Garcia-Garcia, Lorenzo

    2006-01-01

    The purpose of this study was to evaluate, in a prospective, single-center study, the effectiveness of Song's polyurethane stents, modified 'in-house,' in the percutaneous management of epiphora. Patients (n = 170; age range 18-83, mean = 64; 50 male, 120 female) with severe epiphora had the modified stents inserted (183 eyes/195 stents) to treat unilateral/bilateral and complete/partial obstruction of the nasolacrimal system. The etiology of the obstruction was idiopathic in 119 cases (61%) and chronic dacryocystitis in 76 (39%). The set designed by Song was used in all patients but modified by us such that the extreme end is cone-shaped. The original technique was slightly modified by us and the procedure was conducted on an outpatient basis. The initial technical success rate of stent placement was 97%. Resolution of epiphora was complete in 180 eyes and partial in 3. On follow-up (mean = 18 months; range: 2 days to 24 months), 165 of 195 stents (85%) remained patent. Primary patency rates at follow-up were 86%, 84%, 84%, and 79% in the first 6 months, second and third 6 months, and the present (24 months), respectively. Stents became obstructed in 30 patients, but all but 2 were easily withdrawn and 20 of these patients remained asymptomatic for a mean of 14 months (secondary patency of 67%). Following stent removal, the withdrawn stent was replaced with a new stent in the same intervention on 14 occasions. In another six cases, patency was re-established without the need of a second stent. The procedure is simple and safe, both in stent insertion as well as in mechanical de-blocking and withdrawal when occluded. Success was >80 % in the short term (1-year follow-up). Stenting failure does not preclude other treatment because with the modification that we had introduced, the extreme end of the stent becomes more accessible to mechanical de-blocking, withdrawal, and relocation. The levels of primary and secondary patencies are promising and warrant more

  16. Stent thrombosis with drug-eluting and bare-metal stents: evidence from a comprehensive network meta-analysis.

    Science.gov (United States)

    Palmerini, Tullio; Biondi-Zoccai, Giuseppe; Della Riva, Diego; Stettler, Christoph; Sangiorgi, Diego; D'Ascenzo, Fabrizio; Kimura, Takeshi; Briguori, Carlo; Sabatè, Manel; Kim, Hyo-Soo; De Waha, Antoinette; Kedhi, Elvin; Smits, Pieter C; Kaiser, Christoph; Sardella, Gennaro; Marullo, Antonino; Kirtane, Ajay J; Leon, Martin B; Stone, Gregg W

    2012-04-14

    The relative safety of drug-eluting stents and bare-metal stents, especially with respect to stent thrombosis, continues to be debated. In view of the overall low frequency of stent thrombosis, large sample sizes are needed to accurately estimate treatment differences between stents. We compared the risk of thrombosis between bare-metal and drug-eluting stents. For this network meta-analysis, randomised controlled trials comparing different drug-eluting stents or drug-eluting with bare-metal stents currently approved in the USA were identified through Medline, Embase, Cochrane databases, and proceedings of international meetings. Information about study design, inclusion and exclusion criteria, sample characteristics, and clinical outcomes was extracted. 49 trials including 50,844 patients randomly assigned to treatment groups were analysed. 1-year definite stent thrombosis was significantly lower with cobalt-chromium everolimus eluting stents (CoCr-EES) than with bare-metal stents (odds ratio [OR] 0·23, 95% CI 0·13-0·41). The significant difference in stent thrombosis between CoCr-EES and bare-metal stents was evident as early as 30 days (OR 0·21, 95% CI 0·11-0·42) and was also significant between 31 days and 1 year (OR 0·27, 95% CI 0·08-0·74). CoCr-EES were also associated with significantly lower rates of 1-year definite stent thrombosis compared with paclitaxel-eluting stents (OR 0·28, 95% CI 0·16-0·48), permanent polymer-based sirolimus-eluting stents (OR 0·41, 95% CI 0·24-0·70), phosphorylcholine-based zotarolimus-eluting stents (OR 0·21, 95% CI 0·10-0·44), and Resolute zotarolimus-eluting stents (OR 0·14, 95% CI 0·03-0·47). At 2-year follow-up, CoCr-EES were still associated with significantly lower rates of definite stent thrombosis than were bare-metal (OR 0·35, 95% CI 0·17-0·69) and paclitaxel-eluting stents (OR 0·34, 95% CI 0·19-0·62). No other drug-eluting stent had lower definite thrombosis rates compared with bare

  17. Comparison of a New Polytetrafluoroethylene-Covered Metallic Stent to a Noncovered Stent in Canine Ureters

    International Nuclear Information System (INIS)

    Chung, Hwan-Hoon; Lee, Seung Hwa; Cho, Sung Bum; Park, Hong Suk; Kim, Young Sik; Kang, Byung Chul; Frisoli, Joan K.; Razavi, Mahmood K.

    2008-01-01

    The aim of this study was to determine the feasibility of using a newly designed polytetrafluoroethylene (PTFE)-covered metallic stent in the ureter by comparing its effectiveness with that of the noncovered stent in a canine model. We placed 14 stents in the ureters of seven mongrel dogs that weighed 30-40 kg each. The covered and noncovered stents were deployed in the right and left ureters, respectively, of six dogs. In the seventh dog, a covered stent and a double-J catheter were inserted in the right ureter, and a covered stent only was inserted in the left ureter. The first six dogs were sacrificed at 5, 10, and 15 weeks after deployment of the stents (two for each follow-up period), and the seventh dog was sacrificed at 30 weeks. There was no migration or poor expansion of any of the stents observed on plain radiography. On intravenous pyelogram and retrograde pyelogram, all of the covered stents at each follow-up period had patent lumens at the stented segments without hydronephrosis, and the passage of contrast material through it was well preserved. The noncovered stents in the dogs sacrificed at 5 and 10 weeks and one of the two dogs sacrificed at 15 weeks showed near-complete occlusion of the stent lumen due to ingrowth of the soft tissue, and severe hydronephrosis was also noted. The noncovered stent in the other dog sacrificed at 15 weeks showed the passage of contrast material without hydronephrosis, but the lumen of the stent was still nearly occluded by the soft tissue. There was no evidence of hydronephrosis or passage disturbance of the contrast material in both ureters of the dog sacrificed at 30 weeks. We conclude that the newly designed PTFE-covered stent effectively prevented the luminal occlusion caused by urothelial hyperplasia compared to the near-total occlusion of the noncovered stents, and no migration of the covered stents was noted

  18. Treatment of Post-Stent Gastroesophageal Reflux by Anti-Reflux Z-Stent

    International Nuclear Information System (INIS)

    Davies, Roger Philip; Kew, Jacqueline; Byrne, Peter D.

    2000-01-01

    Severe symptoms of heartburn and retrosternal pain consistent with gastro-esophageal reflux (GER) developed in a patient following placement of a conventional self-expanding 16-24-mm-diameter x 12-cm-long esophageal stent across the gastroesophageal junction to treat an obstructing esophageal carcinoma. A second 18-mm-diameter x 10-cm-long esophageal stent with anti-reflux valve was deployed coaxially and reduced symptomatic GER immediately. Improvement was sustained at 4-month follow-up. An anti-reflux stent can be successfully used to treat significant symptomatic GER after conventional stenting

  19. Impact of stent strut design in metallic stents and biodegradable scaffolds.

    Science.gov (United States)

    Foin, Nicolas; Lee, Renick D; Torii, Ryo; Guitierrez-Chico, Juan Luis; Mattesini, Alessio; Nijjer, Sukhjinder; Sen, Sayan; Petraco, Ricardo; Davies, Justin E; Di Mario, Carlo; Joner, Michael; Virmani, Renu; Wong, Philip

    2014-12-20

    Advances in the understanding of healing mechanisms after stent implantation have led to the recognition of stent strut thickness as an essential factor affecting re-endothelialization and overall long term vessel healing response after Percutaneous Coronary Interventions (PCI). Emergence of Drug-eluting stents (DESs) with anti-proliferative coating has contributed to reducing the incidence of restenosis and Target Lesion Revascularization (TVR), while progress and innovations in stent materials have in the meantime facilitated the design of newer platforms with more conformability and thinner struts, producing lesser injury and improving integration into the vessel wall. Recent advances in biodegradable metal and polymer materials now also allow for the design of fully biodegradable platforms, which are aimed at scaffolding the vessel only temporarily to prevent recoil and constrictive remodeling of the vessel during the initial period required, and are then progressively resorbed thereby avoiding the drawback of leaving an unnecessary implant permanently in the vessel. The aim of this article is to review recent evolution in stent material and stent strut design while understanding their impact on PCI outcomes. The article describes the different metallic alloys and biodegradable material properties and how these have impacted the evolution of stent strut thickness and ultimately outcomes in patients. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  20. Self-expandable metalic endotracheal stent

    International Nuclear Information System (INIS)

    Do, Young Soo; Cho, Dae Soon; Cho, Kyung Ja; Lee, Young Soo; Lee, Mi Jae

    1993-01-01

    Six bare stents and six covered stents were inserted in the trachea of 12 dogs under general anesthesia. After 1-10 weeks of observation, the dogs were killed, and the trachea and lung were examined grossly and histologically. Pneumonia and stent migration were observed more frequently at covered stent group. Inflammatory change of the trachea was more severe at covered stent group. In conclusion, we believe that it is inadequate to insert silicone covered stent in the tracheobronchial tree. (Author)

  1. Self-expandable metalic endotracheal stent

    Energy Technology Data Exchange (ETDEWEB)

    Do, Young Soo; Cho, Dae Soon; Cho, Kyung Ja; Lee, Young Soo; Lee, Mi Jae [Korea Cancer Center Hospital, Seoul (Korea, Republic of)

    1993-01-01

    Six bare stents and six covered stents were inserted in the trachea of 12 dogs under general anesthesia. After 1-10 weeks of observation, the dogs were killed, and the trachea and lung were examined grossly and histologically. Pneumonia and stent migration were observed more frequently at covered stent group. Inflammatory change of the trachea was more severe at covered stent group. In conclusion, we believe that it is inadequate to insert silicone covered stent in the tracheobronchial tree. (Author).

  2. Predictive factors for the failure of endoscopic stent-in-stent self-expandable metallic stent placement to treat malignant hilar biliary obstruction.

    Science.gov (United States)

    Sugimoto, Mitsuru; Takagi, Tadayuki; Suzuki, Rei; Konno, Naoki; Asama, Hiroyuki; Watanabe, Ko; Nakamura, Jun; Kikuchi, Hitomi; Waragai, Yuichi; Takasumi, Mika; Sato, Yuki; Hikichi, Takuto; Ohira, Hiromasa

    2017-09-14

    To investigate the factors predictive of failure when placing a second biliary self-expandable metallic stents (SEMSs). This study evaluated 65 patients with an unresectable malignant hilar biliary obstruction who were examined in our hospital. Sixty-two of these patients were recruited to the study and divided into two groups: the success group, which consisted of patients in whom a stent-in-stent SEMS had been placed successfully, and the failure group, which consisted of patients in whom the stent-in-stent SEMS had not been placed successfully. We compared the characteristics of the patients, the stricture state of their biliary ducts, and the implemented endoscopic retrograde cholangiopancreatography (ERCP) procedures between the two groups. The angle between the target biliary duct stricture and the first implanted SEMS was significantly larger in the failure group than in the success group. There were significantly fewer wire or dilation devices (ERCP catheter, dilator, or balloon catheter) passing the first SEMS cell in the failure group than in the success group. The cut-off value of the angle predicting stent-in-stent SEMS placement failure was 49.7 degrees according to the ROC curve (sensitivity 91.7%, specificity 61.2%). Furthermore, the angle was significantly smaller in patients with wire or dilation devices passing the first SEMS cell than in patients without wire or dilation devices passing the first SEMS cell. A large angle was identified as a predictive factor for failure of stent-in-stent SEMS placement.

  3. Auxetic coronary stent endoprosthesis

    DEFF Research Database (Denmark)

    Amin, Faisal; Ali, Murtaza Najabat; Ansari, Umar

    2014-01-01

    BACKGROUND: Cardiovascular heart disease is one of the leading health issues in the present era and requires considerable health care resources to prevent it. The present study was focused on the development of a new coronary stent based on novel auxetic geometry which enables the stent to exhibit...... a negative Poisson's ratio. Commercially available coronary stents have isotropic properties, whereas the vascular system of the body shows anisotropic characteristics. This results in a mismatch between anisotropic-isotropic properties of the stent and arterial wall, and this in turn is not favorable...... for mechanical adhesion of the commercially available coronary stents with the arterial wall. It is believed that an auxetic coronary stent with inherent anisotropic mechanical properties and negative Poisson's ratio will have good mechanical adhesion with the arterial wall. METHODS: The auxetic design...

  4. A method to determine the kink resistance of stents and stent delivery systems according to international standards

    Directory of Open Access Journals (Sweden)

    Brandt-Wunderlich Christoph

    2016-09-01

    Full Text Available The kink behavior of vascular stents is of particular interest for clinicians, stent manufacturers and regulatory as a kinked stent generates a lumen loss in the stented vessel and can lead to in-stent restenosis. In this study methods to determine the kink resistance of stents and stent delivery systems according to the ISO 25539-2 and FDA guidance no. 1545 were presented. The methods are applicable for balloon expandable stents as well as for self-expanding stents and determine the lumen loss and residual diameter change dependent on the specific bending radius.

  5. Future developments in biliary stenting

    Science.gov (United States)

    Hair, Clark D; Sejpal, Divyesh V

    2013-01-01

    Biliary stenting has evolved dramatically over the past 30 years. Advancements in stent design have led to prolonged patency and improved efficacy. However, biliary stenting is still affected by occlusion, migration, anatomical difficulties, and the need for repeat procedures. Multiple novel plastic biliary stent designs have recently been introduced with the primary goals of reduced migration and improved ease of placement. Self-expandable bioabsorbable stents are currently being investigated in animal models. Although not US Food and Drug Administration approved for benign disease, fully covered self-expandable metal stents are increasingly being used in a variety of benign biliary conditions. In malignant disease, developments are being made to improve ease of placement and stent patency for both hilar and distal biliary strictures. The purpose of this review is to describe recent developments and future directions of biliary stenting. PMID:23837001

  6. Endothelial cell repopulation after stenting determines in-stent neointima formation: effects of bare-metal vs. drug-eluting stents and genetic endothelial cell modification.

    Science.gov (United States)

    Douglas, Gillian; Van Kampen, Erik; Hale, Ashley B; McNeill, Eileen; Patel, Jyoti; Crabtree, Mark J; Ali, Ziad; Hoerr, Robert A; Alp, Nicholas J; Channon, Keith M

    2013-11-01

    Understanding endothelial cell repopulation post-stenting and how this modulates in-stent restenosis is critical to improving arterial healing post-stenting. We used a novel murine stent model to investigate endothelial cell repopulation post-stenting, comparing the response of drug-eluting stents with a primary genetic modification to improve endothelial cell function. Endothelial cell repopulation was assessed en face in stented arteries in ApoE(-/-) mice with endothelial-specific LacZ expression. Stent deployment resulted in near-complete denudation of endothelium, but was followed by endothelial cell repopulation, by cells originating from both bone marrow-derived endothelial progenitor cells and from the adjacent vasculature. Paclitaxel-eluting stents reduced neointima formation (0.423 ± 0.065 vs. 0.240 ± 0.040 mm(2), P = 0.038), but decreased endothelial cell repopulation (238 ± 17 vs. 154 ± 22 nuclei/mm(2), P = 0.018), despite complete strut coverage. To test the effects of selectively improving endothelial cell function, we used transgenic mice with endothelial-specific overexpression of GTP-cyclohydrolase 1 (GCH-Tg) as a model of enhanced endothelial cell function and increased NO production. GCH-Tg ApoE(-/-) mice had less neointima formation compared with ApoE(-/-) littermates (0.52 ± 0.08 vs. 0.26 ± 0.09 mm(2), P = 0.039). In contrast to paclitaxel-eluting stents, reduced neointima formation in GCH-Tg mice was accompanied by increased endothelial cell coverage (156 ± 17 vs. 209 ± 23 nuclei/mm(2), P = 0.043). Drug-eluting stents reduce not only neointima formation but also endothelial cell repopulation, independent of strut coverage. In contrast, selective targeting of endothelial cell function is sufficient to improve endothelial cell repopulation and reduce neointima formation. Targeting endothelial cell function is a rational therapeutic strategy to improve vascular healing and decrease neointima formation after stenting.

  7. Endoscopic stent suture fixation for prevention of esophageal stent migration during prolonged dilatation for achalasia treatment.

    Science.gov (United States)

    Rieder, E; Asari, R; Paireder, M; Lenglinger, J; Schoppmann, S F

    2017-04-01

    The aim of this study is to compare endoscopic stent suture fixation with endoscopic clip attachment or the use of partially covered stents (PCS) regarding their capability to prevent stent migration during prolonged dilatation in achalasia. Large-diameter self-expanding metal stents (30 mm × 80 mm) were placed across the gastroesophageal junction in 11 patients with achalasia. Stent removal was scheduled after 4 to 7 days. To prevent stent dislocation, endoscopic clip attachment, endoscopic stent suture fixation, or PCS were used. The Eckardt score was evaluated before and 6 months after prolonged dilatation. After endoscopic stent suture fixation, no (0/4) sutured stent migrated. When endoscopic clips were used, 80% (4/5) clipped stents migrated (p = 0.02). Of two PCS (n = 2), one migrated and one became embedded leading to difficult stent removal. Technical adverse events were not seen in endoscopic stent suture fixation but were significantly correlated with the use of clips or PCS (r = 0.828, p = 0.02). Overall, 72% of patients were in remission regarding their achalasia symptoms 6 months after prolonged dilatation. Endoscopic suture fixation of esophageal stents but not clip attachment appears to be the best method of preventing early migration of esophageal stents placed at difficult locations such as at the naive gastroesophageal junction. © The Authors 2017. Published by Oxford University Press on behalf of International Society for Diseases of the Esophagus. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  8. Percutaneous biliary drainage and stenting

    International Nuclear Information System (INIS)

    Totev, M.

    2012-01-01

    Full text: Percutaneous transhepatic cholangiography (PTC) is an X-ray or US guided procedure that involves the injection of a contrast material directly into the bile ducts inside the liver to produce pictures of them. If a blockage or narrowing is found, additional procedures may be performed: 1. insertion of a catheter to drain excess bile out of the body or both - internal and external; 2. plastic endoprothesis placement; 3. self-expandable metal stents placement to help open bile ducts or to bypass an obstruction and allow fluids to drain. Current percutaneous biliary interventions include percutaneous transhepatic cholangiography (PTC) and biliary drainage to manage benign and malignant obstructions. Internal biliary stents are either plastic or metallic, and various types of each kind are available. Internal biliary stents have several advantages. An external tube can be uncomfortable and have a psychological disadvantage. An internal stent prevents the problems related to external catheters, for example, pericatheter leakage of bile and the need for daily flushing. The disadvantages include having to perform endoscopic retrograde cholangiopancreatography (ERCP) or new PTC procedures to obtain access in case of stent obstruction. Better patency rates are reported with metallic than with plastic stents in cases of malignant obstruction, though no effect on survival is noted. Plastic internal stents are the cheapest but reportedly prone to migration. Metallic stents are generally not used in the treatment of benign disease because studies have shown poor long-term patency rates. Limited applications may include the treatment of patients who are poor surgical candidates or of those in whom surgical treatment fails. Most postoperative strictures are treated surgically, though endoscopic and (less commonly) percutaneous placement of nonmetallic stents has increasingly been used in the past few years. Now there are some reports about use of biodegradable biliary

  9. Tratamiento paliativo de la obstrucción tumoral del vaciamiento gástrico con prótesis metálicas autoexpandibles insertadas endoscópicamente Palliative management of malignant gastric outlet obstruction with endoscopically inserted self-expanding metal stents

    Directory of Open Access Journals (Sweden)

    J. García-Cano

    2008-06-01

    Full Text Available Antecedentes y objetivo: la inserción de prótesis metálicas autoexpandibles para paliar la obstrucción tumoral del vaciamiento gástrico es un procedimiento mínimamente invasivo, que cada vez se utiliza con más frecuencia. Presentamos la experiencia de esta técnica en un hospital de nivel II del Sistema Nacional de Salud. Pacientes y métodos: estudio retrospectivo de un periodo de cinco años (2003-2007, en los que se trató de resolver la obstrucción tumoral del vaciamiento gástrico en 27 ocasiones a 23 pacientes (media de 0,45 procedimientos por mes, mediante la inserción endoscópica de prótesis no recubiertas (Wallstent® y Wallflex®. Resultados: la inserción fue técnicamente posible en el 100% de los 27 intentos. Se obtuvo un buen resultado clínico en 25 ocasiones (92,5%. Se utilizó sólo endoscopia 10 (37% veces y en las otras 17 (63% también fluoroscopia. Tras la inserción de la prótesis se intervino a un paciente con intención curativa y a otro, en el que la prótesis no funcionó, para realizar una derivación paliativa. Cuatro prótesis se obstruyeron por crecimiento tumoral, recanalizándose mediante la inserción de nuevas prótesis. En tres ocasiones se produjo ictericia obstructiva en prótesis que cubrían la papila de Vater. No hubo otras complicaciones. Tampoco mortalidad derivada del procedimiento. La media de supervivencia fue de 104 días (rango 28-400, DE ± 94. Conclusiones: en nuestra experiencia, la inserción endoscópica de prótesis metálicas autoexpandibles parece un método seguro y eficaz en el tratamiento paliativo de la obstrucción tumoral del vaciamiento gástrico y puede llevarse a cabo con éxito en un centro de nuestras características.Aim and background: the insertion of self-expanding metal stents to palliate malignant gastric outlet obstruction is a minimally invasive procedure that is being increasingly used. We discuss experience with this technique in a level-II hospital in the

  10. [Absorbable coronary stents. New promising technology].

    Science.gov (United States)

    Erbel, Raimund; Böse, Dirk; Haude, Michael; Kordish, Igor; Churzidze, Sofia; Malyar, Nasser; Konorza, Thomas; Sack, Stefan

    2007-06-01

    Coronary stent implantation started in Germany 20 years ago. In the beginning, the progress was very slow and accelerated 10 years later. Meanwhile, coronary stent implantation is a standard procedure in interventional cardiology. From the beginning of permanent stent implantation, research started to provide temporary stenting of coronary arteries, first with catheter-based systems, later with stent-alone technology. Stents were produced from polymers or metal. The first polymer stent implantation failed except the Igaki-Tamai stent in Japan. Newly developed absorbable polymer stents seem to be very promising, as intravascular ultrasound (IVUS) and optical coherence tomography have demonstrated. Temporary metal stents were developed based on iron and magnesium. Currently, the iron stent is tested in peripheral arteries. The absorbable magnesium stent (Biotronik, Berlin, Germany) was tested in peripheral arteries below the knee and meanwhile in the multicenter international PROGRESS-AMS (Clinical Performance and Angiographic Results of Coronary Stenting with Absorbable Metal Stents) study. The first magnesium stent implantation was performed on July 30, 2004 after extended experimental testing in Essen. The magnesium stent behaved like a bare-metal stent with low recoil of 5-7%. The stent struts were absorbed when tested with IVUS. Stent struts were not visible by fluoroscopy or computed tomography (CT) as well as magnetic resonance imaging (MRI). That means, that the magnesium stent is invisible and therefore CT and MRI can be used for imaging of interventions. Only using micro-CT the stent struts were visible. The absorption process could be demonstrated in a patient 18 days after implantation due to suspected acute coronary syndrome, which was excluded. IVUS showed a nice open lumen. Stent struts were no longer visible, but replaced by tissue indicating the previous stent location. Coronary angiography after 4 months showed an ischemia-driven target lesion

  11. Drug-eluting stents and bare metal stents in patients with NSTE-ACS

    DEFF Research Database (Denmark)

    Pedersen, Sune Haahr; Pfisterer, Matthias; Kaiser, Christoph

    2014-01-01

    the randomised BASKET-PROVE trial (sirolimus-eluting stent vs. everolimus-eluting stent vs. bare metal stent in large-vessel stenting). The primary endpoint was the combined two-year rate of cardiovascular death or non-fatal myocardial infarction (MI). Secondary endpoints were each component of the primary...... implantation in large vessels was associated with a reduction in both TVR and the combined endpoint consisting of cardiovascular death/MI. Thus, DES use improves both efficacy and safety. These findings support the use of DES in NSTE-ACS patients....

  12. Percutaneous placement of ureteral stent

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Seung Hyup; Park, Jae Hyung; Han, Joon Koo; Han, Man Chung [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    1990-12-15

    Antegrade placement of ureteral stents has successfully achieved in 41 of 46 ureters. When it was difficult to advance ureteral stents through the lesion, it was facilitated by retrograde guide-wire snare technique through urethra. Complications associated with the procedure were non-function of ureteral stent by occlusion, upward migration,and spontaneous fracture of ureteral stent. These complications were managed by percutaneous nephrostomy and removal of ureteral stents by guide-wire snare technique and insertion of a new ureteral stent. While blood cell in urine was markedly increased in about 50% of patients following the procedure.

  13. Covered duodenal self-expandable metal stents prolong biliary stent patency in double stenting: The largest series of bilioduodenal obstruction.

    Science.gov (United States)

    Hori, Yasuki; Naitoh, Itaru; Hayashi, Kazuki; Kondo, Hiromu; Yoshida, Michihiro; Shimizu, Shuya; Hirano, Atsuyuki; Okumura, Fumihiro; Ando, Tomoaki; Jinno, Naruomi; Takada, Hiroki; Togawa, Shozo; Joh, Takashi

    2018-03-01

    Endoscopic biliary and duodenal stenting (DS; double stenting) is widely accepted as a palliation therapy for malignant bilioduodenal obstruction. The aim of the current study was to investigate the patency and adverse events of duodenal and biliary stents in patients with DS. Patients who underwent DS from April 2004 to March 2017 were analyzed retrospectively with regard to clinical outcomes and predictive factors of recurrent biliary and duodenal obstruction (recurrent biliary obstruction [RBO] and recurrent duodenal obstruction [RDO]). A total of 109 consecutive patients was enrolled. Technical success of DS was achieved in 108 patients (99.1%). Symptoms due to biliary and duodenal obstruction were improved in 89 patients (81.7%). RBO occurred in 25 patients (22.9%) and RDO in 13 (11.9%). The median times to RBO and RDO from DS were 87 and 76 days, respectively. Placement of a duodenal uncovered self-expandable metal stent (U-SEMS) was significantly associated with RBO in the multivariable analysis (P = 0.007). Time to RBO was significantly longer in the duodenal covered self-expandable metal stent group than in the U-SEMS group (P = 0.003). No predictive factors of RDO were detected, and duodenal stent type was not associated with the time to RDO (P = 0.724). Double stenting was safe and effective for malignant bilioduodenal obstruction. Duodenal U-SEMS is a risk factor for RBO. The covered self-expandable metal stent is the preferred type of duodenal SEMS in patients with DS (Clinical trial registration number: UMIN000027606). © 2017 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.

  14. Implante de stent dentro de stent recém-implantado em ponte de veia safena para otimização do resultado angiográfico Stenting a stent in saphenous vein graft to optimize the angiographic result

    Directory of Open Access Journals (Sweden)

    Antonio Esteves Fº

    1998-03-01

    Full Text Available Mulher de 60 anos, com angina progressiva e revascularização do miocárdio, há oito anos, com ponte de veia safena para coronária direita e anastomose de artéria mamaria esquerda para artéria descendente anterior. Submetida a implante de stent Gianturco-Roubin II em terço proximal da ponte de veia safena para artéria coronária direita, com resultado insatisfatório pela persistência de lesão residual, provavelmente, decorrente de prolapso para dentro da luz de material aterosclerótico através dos coils. Foi implantado outro stent (Palmaz-Schatz biliar dentro do stent GRII com sucesso e ótimo resultado angiográfico. Um 2º stent Palmaz-Schatz biliar foi implantado em lesão distal no corpo da ponte, ultrapassando os dois stents, anteriormente implantados, com sucesso. Em algumas situações, implante de stent dentro de outro stent é recurso útil para otimização de resultado angiográfico do implante de um stent.A 60 year-old woman with progressive angina who had been submitted to saphenous bypass-graft to right coronary artery and a left mammary artery graft to anterior descending artery eight years previously, underwent implantation of a Gianturco Roubin II stent in the proximal third of the saphenous vein graft. The result was suboptimal by persistence of a residual stenosis probably due to prolapse of atherosclerotic material through the coil spaces. Another stent (Palmaz-Schatz biliar stent was implanted at the previously stented site with no residual stenosis. Another Palmaz-Schatz biliar stent was successfully implanted in the distal body of the graft to treat another lesion (passing through the previously stents without difficulty. Stenting a stent, in selected situations, is a useful tool to optimize the angiographic result of stent implantation.

  15. [Cost-effectiveness trial of self-expandable metal stents and plastic biliary stents in malignant biliary obstruction].

    Science.gov (United States)

    Daróczi, Tímea; Bor, Renáta; Fábián, Anna; Szabó, Ella; Farkas, Klaudia; Bálint, Anita; Czakó, László; Rutka, Mariann; Szűcs, Mónika; Milassin, Ágnes; Molnár, Tamás; Szepes, Zoltán

    2016-02-14

    Self-expandable metal and plastic stents can be applied in the palliative endoscopic treatment of patients with unresectable malignant biliary obstruction. The use of metal stentsis recommended if the patient's life expectancy is more than four months. To compare the therapeutic efficacy and cost-effectiveness of metal and plastic stents in the treatment of malignant biliary obstruction. The authors retrospectively enrolled patients who received metal (37 patients) or plastic stent (37 patients). The complication rate, stent patency and cumulative cost of treatment were assessed in the two groups. The complication rate of metal stents was lower (37.84% vs. 56.76%), but the stent patency was higher compared with plastic stents (19.11 vs. 8.29 weeks; p = 0.0041). In the plastic stent group the frequency of hospitalization of patients in context with stent complications (1.18 vs. 2.32; p = 0.05) and the necessity of reintervention for stent dysfunction (17 vs. 27; p = 0.033) were substantially higher. In this group multiple stent implantation raised the stent patency from 7.68 to 10.75 weeks. There was no difference in the total cost of treatment of malignant biliary obstruction between the two groups (p = 0.848). Considering the cost of treatment and the burden of patients the authors recommend self-expandable metal sten timplantation if the life expectancy of patients is more than two months. In short survival cases multiple plastic stent implantation is recommended.

  16. Experimental absorbable stent permits airway remodeling.

    Science.gov (United States)

    Liu, Kuo-Sheng; Liu, Yun-Hen; Peng, Yi-Jie; Liu, Shih-Jung

    2011-02-01

    Despite metallic and silicone stents being effective in treating various airway lesions, many concerns still remain. A bioresorbable stent that scaffolds the airway lumen and dissolves after the remodeling process is completed has advantages over metallic and silicone stents. We designed and fabricated a new mesh-type bioresorbable stent with a backbone of polycaprolactone (PCL), and evaluated its safety and biocompatibility in a rabbit trachea model. The PCL stent was fabricated by a laboratory-made microinjection molding machine. In vitro mechanical strength of the PCL stents was tested and compared to that of commercial silicone stents. The bioresorbable stents were surgically implanted into the cervical trachea of New Zealand white rabbits (n=6). Animals received bronchoscopic examination at 1, 2, 4, 8, and 12 weeks after surgery. Histological examination was completed to evaluate the biocompatibility of the stents. No animals died during the period of study. Distal stent migration was noted in 1 rabbit. In-stent secretion accumulation was found in 2 rabbits. Histological examination showed intact ciliated epithelium and marked leukocyte infiltration in the submucosa of the stented area at 10 and 28 weeks. Stent degradation was minimal, and the mechanical strength was well preserved at the end of 33 weeks. These preliminary findings showed good safety and biocompatibility of the new PCL stent when used in the airway remodeling. PCL could be a promising bioresorbable material for stent design if prolonged degradation time is required. Copyright © 2011 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.

  17. Management of stent dislodgment in coarctoplasty of aorta with three overlapping self-expandable nitinol stents.

    Science.gov (United States)

    Ghazi, Payam; Haji-Zeinali, Ali-Mohammad

    2010-01-01

    We describe a case of native coarctation of aorta managed with three self-expandable nitinol stents. After balloon pre-dilation, the first and second stents were dislodged. The coarcted area was successfully treated with the third stent overlapped with the previous stents. During follow up (30 months), the patient was free of complications. It seems that implantation of multiple overlapping self-expandable stents in aortic coarctation patients, if needed, is safe and possible.

  18. MRT of carotid stents: influence of stent properties and sequence parameters on visualization of the carotid artery lumen

    International Nuclear Information System (INIS)

    Straube, T.; Wolf, S.; Alfke, K.; Jansen, O.; Flesser, A.; Deli, M.; Nabavi, A.

    2005-01-01

    Purpose: To evaluate MR artifacts of carotid artery stents and to optimize stent properties and sequence parameters. Material and Methods: Four carotid artery stents - Wallstent (mediloy), Precise (nitinol), ACCULINK (nitinol) and a stent prototype (nitinol) - were investigated in a flow model of the cervical vessels. The model was made of silicon tubing and a flow pump that produces realistic flow curves of the carotid artery. To investigate the effects of magnetic susceptibility and radiofrequency induced shielding artifacts, turbo spin echo and gradient echo sequences as well as CE-MRAs were measured. To improve the visualization of the stent lumen in a CE-MRA, flip angle as well as geometry and covering of the stent prototype were altered. Results: Susceptibility artifacts in stents of the carotid artery only influence the lumen visualization at the proximal and distal end of the braided mediloy stent. A change of stent coverings has no significant influence on radiofrequency artifacts, whereas a reduction in linking elements between stent segments and a change in diameter of stent struts improves visualization of the stent lumen. By increasing the flip angle in a CE-MRA, visualization of the stent lumen is possible in both mediloy and nitinol stents. Conclusion: The choice of stent material and changes in stent geometry as well as the optimization of the flip angle of the CE-MRA may reduce susceptibility and radiofrequency artifacts, rendering feasible the CE-MRA of a stented carotid artery. (orig.)

  19. Impacto da insuficiência renal crônica na eficácia de stents farmacológicos: estudo de seguimento de longo prazo

    Directory of Open Access Journals (Sweden)

    Vitor Osório Gomes

    2011-05-01

    Full Text Available FUNDAMENTO: Pacientes com Insuficiência Renal Crônica (IRC submetidos à angioplastia coronária apresentam maiores taxas de revascularização da lesão alvo (RLA e mortalidade. Os stents farmacológicos (SF estão associados com taxas menores de reestenose, quando comparados aos stents não farmacológicos (SNF, embora em pacientes com IRC os dados da eficácia e segurança do SF sejam limitados. OBJETIVO: Buscamos avaliar a segurança e eficácia dos SF em pacientes com IRC significante, quando comparados a pacientes com função renal normal em um registro da "vida real". MÉTODOS: 504 pacientes submetidos à intervenção coronariana percutânea com SF em dois centros foram incluídos. Os desfechos foram estratificados baseados na presença de IRC, definida como taxa de filtração glomerular basal < 60 ml/min/1,73 m². RESULTADOS: O acompanhamento médio foi de 22,7 meses. A IRC estava presente em 165 pacientes (32,7%. Pacientes com IRC eram mais velhos, tinham mais hipertensão e diabete. Pacientes com IRC apresentaram maior incidência de morte (12,3% vs 2,4%, p < 0,001 e infarto do miocárdio (IM (7,4% vs 3,3%, p = 0,04, quando comparados aos pacientes sem IRC. Taxas de RLA foram similares entre os grupos (4.8% vs 5.6%, p = 0,7, pacientes com e sem IRC, respectivamente. Preditores independentes de morte foram a IRC (HR 6,93; 2,4 - 19,5, p < 0,001, tabagismo atual (HR 3,66; 1,20 - 11,10, p = 0,02 e diabete (HR 2,66; 1,3 - 6,60, p = 0,045. CONCLUSÃO: Neste registro, a intervenção coronariana com SF em pacientes com IRC foi associada com RLA similar comparada aos pacientes sem IRC, demonstrando a eficácia dos FS na prevenção da reestenose intra-stent nessa população de pacientes. A IRC foi relacionada a um aumento significativo das taxas de IM e mortalidade.

  20. Modified nasolacrimal duct stenting

    International Nuclear Information System (INIS)

    Tian Min; Jin Mei; Chen Huanjun; Li Yi

    2008-01-01

    Objective: Traditional nasolacrimal duct stenting possesses some shortcoming including difficulty of pulling ball head guide wire from the nasal cavity with turbinate hypertrophy and nasal septal deviation. The new method of nose-oral tube track establishment can overcome the forementioned and increase the successful rate. Methods: 5 F catheter and arterial sheath were modified to be nasolacrimal duct stent delivery device respectively. Antegrade dacryocystography was taken firstly to display the obstructed site and followed by the modified protocol of inserting the guide wire through nasolacrimal duct and nasal cavity, and establishing the stent delivery track for retrograde stent placement. Results: 5 epiphora patients with failure implantation by traditional method were all succeeded through the modified stenting (100%). During 6-mouth follow-up, no serious complications and reocclusion occurred. Conclusion: The establishment of eye-nose-mouth-nose of external nasal guide wire track can improve the successful rate of nasolacrimal duct stenting. (authors)

  1. Compliance Study of Endovascular Stent Grafts Incorporated with Polyester and Polyurethane Graft Materials in both Stented and Unstented Zones

    Directory of Open Access Journals (Sweden)

    Ying Guan

    2016-08-01

    Full Text Available Compliance mismatch between stent graft and host artery may induce complications and blood flow disorders. However, few studies have been reported on stent graft compliance. This study aims to explore the deformation and compliance of stent graft in stented and unstented zones under three pressure ranges. Compliance of two stent grafts incorporated with polyurethane graft (nitinol-PU and polyester graft (nitinol-PET materials respectively were tested; the stents used in the two stent grafts were identical. For the circumferential deformation of the stent grafts under each pressure range, the nitinol-PET stent graft was uniform in both zones. The nitinol-PU stent graft was circumferentially uniform in the stented zone, however, it was nonuniform in the unstented zone. The compliance of the PU graft material was 15 times higher than that of the PET graft. No significant difference in compliance was observed between stented and unstented zones of the nitinol-PET stent graft regardless of the applied pressure range. However, for the nitinol-PU stent graft, compliance of the unstented PU region was approximately twice that of the stented region; thus, compliance along the length of the nitinol-PU stent graft was not constant and different from that of the nitinol-PET stent graft.

  2. Therapies targeting inflammation after stent implantation.

    Science.gov (United States)

    Okura, Hiroyuki; Takagi, Tsutomu; Yoshida, Kiyoshi

    2013-07-01

    Since the introduction of coronary vessel scaffold by metallic stent, percutaneous coronary intervention has become widely performed all over the world. Although drug-eluting stent technology has further decrease the incidence of in-stent restenosis, there still remaining issues related to stent implantation. Vessel inflammation is one of the causes that may be related to stent restenosis as well as stent thrombosis. Therefore, systemic therapies targeting inflammation emerged as adjunctive pharmacological intervention to improve outcome. Statins, corticosteroids, antiplatelets, and immunosuppresive or anti-cancer drugs are reported to favorably impact outcome after bare-metal stent implantation. In type 2 diabetic patients, pioglitazone may be the most promising drug that can lower neointimal proliferation and, as a result, lower incidence of restenosis and target lesion revascularization. On the other hand, several new stent platforms that might decrease inflammatory response after drug-eluting stent implantation have been introduced. Because durable polymer used in the first generation drug-eluting stents are recognized to be responsible for unfavorable vessel response, biocompatible or bioabsorbable polymer has been introduce and already used clinically. Furthermore, polymer-free drug-eluting stent and bioresorbable scaffold are under investigation. Although vessel inflammation may be reduced by using these new drug-eluting stents or scaffold, long-term impact needs to be investigated further.

  3. Transient coronary aneurysm formation after Nevo™ stent implantation versus persistent coronary aneurysm after Cypher Select™ stent implantation

    DEFF Research Database (Denmark)

    Christiansen, Evald Høj; Lassen, Jens Flensted; Jensen, Lisette Okkels

    2011-01-01

    We implanted a Cypher Select™ coronary stent and two months later a Nevo™ sirolimus-eluting coronary stent in another vessel. At a prescheduled angiographic follow-up, coronary aneurysms were seen in the two stented segments, 6 and 8 months after stent implantation, respectively. Six months later......, the aneurysm had healed in the Nevo, but was still present in the Cypher stented segment. We hypothesize that aneurysm formation was induced by sirolimus and the polymer of the implanted stents, and that subsequent healing was possible in the Nevo stent after degradation of the polymer....

  4. Forgotten Ureteral Stents: An Avoidable Morbidity

    International Nuclear Information System (INIS)

    Murtaza, B.; Alvi, S.

    2016-01-01

    Objective: To assess the clinical presentation of forgotten ureteral stents and highlight the etiological factors resulting in the retention of these stents. Study Design: Observational study. Place and Duration of Study: Department of Urology, Armed Forces Institute of Urology, Rawalpindi, from January 2010 to Jun 2011. Methodology: Thirty-eight patients, with forgotten ureteral stents, retained for more than 6 months duration, were enrolled. A detailed evaluation was performed, along with the questions regarding the patients' opinion about the ureteral stents. They were specially asked whether they knew about the stents or were they formally informed regarding the stents. Subsequently, the patients were managed according to their clinical condition. Results: The male to female ratio was 2.1:1 aged 23 - 69 years, mean being 40.24 ± 12.59 years. The time of presentation after the ureteral stenting was 7 - 180 months (mean = 28.89 ± 33.435 years). Seven patients (18.4 percentage) reported with chronic kidney disease, including ESRD in two cases. Recurrent UTI was seen in 28 cases (73.6 percentage), calculus formed over the stents in 20 cases (52.6 percentage), and stent fragmented in 5 patients (13.1 percentage). Majority of patients, (n = 23, 60.5 percentage), were not even aware of the placement of these stents while 8 (21.0 percentage) knew but were reluctant about its removal. In 3 cases (7.8 percentage), the relatives knew about the stent but never informed the patients. The stent had been removed in 2 cases (5.2 percentage), but the other broken fragment was missed. One case (2.6 percentage) each had a misconception about the permanent placement of the stents like cardiac stents and regarding degradation of the stents in situ. Conclusion: Forgotten ureteral stents produce clinical features ranging from recurrent UTI to ESRD. This preventable urological complication is primarily due to the unawareness or ignorance of the patients and their relatives

  5. Stent underexpansion in angiographic guided percutaneous coronary intervention, despite adjunctive balloon post-dilatation, in drug eluting stent era

    Directory of Open Access Journals (Sweden)

    Mehrdad Taherioun

    2014-01-01

    Full Text Available BACKGROUND: Stent underexpansion is the most powerful predictor of long-term stent patency and clinical outcome. The purpose of this study was to evaluate the incidence and predictors of stent underexpansion despite adjunctive post-dilatation with non-compliant balloon. METHODS: After elective coronary stent implantation and adjunctive post-dilatation with non-compliant balloon and optimal angiographic result confirmed by the operator, intravascular ultrasound (IVUS was performed for all the treated lesions. If the treated lesions fulfilled the IVUS criteria, they are considered as the optimal stent group; if not, they are considered as the suboptimal group. RESULTS: From 50 patients enrolled in this study 39 (78% had optimal stent deployment and 11 (22% had suboptimal stent deployment. In the suboptimal group 7 (14% had underexpansion, 2 (4% malposition, and 2 (4% had asymmetry. There were no stent edge dissections detected by IVUS. We did not find any correlation between lesion calcification, ostial lesions, stent length, and stent underexpansion. Stent diameter ≤ 2.75 mm had a strong correlation with stent underexpansion. CONCLUSION: Despite adjunctive post-dilatation with noncompliant balloon, using a relatively small stent diameter was a strong predictor for underexpansion. IVUS guided percutaneous coronary intervention (PCI may be considered for drug eluting stent (DES implantation in relatively small vessels.   Keywords: Stent, Percutaneous Coronary Intervention, Ultrasound, Post-dilatation 

  6. Metallic Limus-Eluting Stents Abluminally Coated with Biodegradable Polymers: Angiographic and Clinical Comparison of a Novel Ultra-Thin Sirolimus Stent Versus Biolimus Stent in the DESTINY Randomized Trial.

    Science.gov (United States)

    Lemos, Pedro A; Abizaid, Alexandre A C; Meireles, George C; Sarmento-Leite, Rogério; Prudente, Mauricio; Cantarelli, Marcelo; Dourado, Adriano D; Mariani, Jose; Perin, Marco A; Costantini, Costantino; Costa, Ricardo A; Costa, José Ribamar; Chamie, Daniel; Campos, Carlos A; Ribeiro, Expedito

    2015-12-01

    To evaluate the outcomes of patients treated with a new drug-eluting stent formulation with low doses of sirolimus, built in an ultra-thin-strut platform coated with biodegradable abluminal coating. This study is a randomized trial that tested the main hypothesis that the angiographic late lumen loss of the novel sirolimus-eluting stent is noninferior compared with commercially available biolimus-eluting stent. A final study population comprising 170 patients with one or two de novo lesions was randomized in the ratio 2:1 for sirolimus-eluting stent or biolimus-eluting stent, respectively. The primary endpoint was 9-month angiographic in-stent late lumen loss. Adverse clinical events were prospectively collected for 1 year. After 9 months, the novel sirolimus-eluting stent was shown noninferior compared with the biolimus stent for the primary endpoint (angiographic in-stent late lumen loss: 0.20 ± 0.29 mm vs. 0.15 ± 0.20 mm, respectively; P value for noninferiority <0.001). The 1-year incidence of death, myocardial infarction, repeat revascularization, and stent thrombosis remained low and not significantly different between the groups. The present randomized trial demonstrates that the tested novel sirolimus-eluting stent was angiographically noninferior in comparison with a last-generation biolimus-eluting stent. © 2015 John Wiley & Sons Ltd.

  7. [The Predictive Factors of Stent Failure in the Treatment of Malignant Extrinsc Ureteral Obstruction Using Internal Ureteral Stents].

    Science.gov (United States)

    Matsuura, Hiroshi; Arase, Shigeki; Hori, Yasuhide; Tochigi, Hiromi

    2017-12-01

    In this study, we retrospectively reviewed the experiences at our single institute in the treatment of malignant extrinsic ureteral obstruction (MUO) using ureteral stents to investigate the clinical outcomes and the predictive factors of stent failure. In 52 ureters of 38 patients who had radiologically significant hydronephrosis due to MUO, internal ureteral stents (The BARD(R) INLAY(TM) ureteral stent set) were inserted. The median follow-up interval after the initial stent insertion was 124.5 days (4-1,120). Stent failure occurred in 8 ureters (15.4%) of the 7 patients. The median interval from the first stent insertion to stent failure was 88 days (1-468). A Cox regression multivariate analysis showed that the significant predictors of stent failure were bladder invasion. Based on the possibility of stent failure, the adaptation of the internal ureteral stent placement should be considered especially in a patient with MUO combined with bladder invasion.

  8. A novel balloon assisted two-stents telescoping technique for repositioning an embolized stent in the pulmonary conduit.

    Science.gov (United States)

    Kobayashi, Daisuke; Gowda, Srinath T; Forbes, Thomas J

    2014-08-01

    A 9-year-old male, with history of pulmonary atresia and ventricular septal defect, status post complete repair with a 16 mm pulmonary homograft in the right ventricular outflow tract (RVOT) underwent 3110 Palmaz stent placement for conduit stenosis. Following deployment the stent embolized proximally into the right ventricle (RV). We undertook the choice of repositioning the embolized stent into the conduit with a transcatheter approach. Using a second venous access, the embolized stent was carefully maneuvered into the proximal part of conduit with an inflated Tyshak balloon catheter. A second Palmaz 4010 stent was deployed in the distal conduit telescoping through the embolized stent. The Tyshak balloon catheter was kept inflated in the RV to stabilize the embolized stent in the proximal conduit until it was successfully latched up against the conduit with the deployment of the overlapping second stent. One year later, he underwent Melody valve implantation in the pre-stented conduit relieving conduit insufficiency. This novel balloon assisted two-stents telescoping technique is a feasible transcatheter option to secure an embolized stent from the RV to the RVOT. © 2014 Wiley Periodicals, Inc.

  9. Air cholangiography in endoscopic bilateral stent-in-stent placement of metallic stents for malignant hilar biliary obstruction.

    Science.gov (United States)

    Lee, Jae Min; Lee, Sang Hyub; Jang, Dong Kee; Chung, Kwang Hyun; Park, Jin Myung; Paik, Woo Hyun; Lee, Jun Kyu; Ryu, Ji Kon; Kim, Yong-Tae

    2016-03-01

    Although endoscopic bilateral stent-in-stent (SIS) placement of self-expandable metallic stents (SEMS) is one of the major palliative treatments for unresectable malignant hilar biliary obstruction, post-endoscopic retrograde cholangiopancreatography (ERCP) cholangitis can occur frequently due to inadequate drainage, especially after contrast injection into the biliary tree. The aim of this study is to evaluate the efficacy and safety of air cholangiography-assisted stenting. This study included 47 patients with malignant hilar biliary obstruction who underwent endoscopic bilateral SEMS placement using the SIS technique. They were divided into two groups, air (n = 23) or iodine contrast (n = 24) cholangiography. We retrospectively compared comprehensive clinical and laboratory data of both groups. There were no significant differences found between the two groups with respect to technical success (87% versus 87.5%, air versus contrast group, respectively), functional success (95% versus 95.2%), 30-day mortality (8.3% versus 8.7%) and stent patency. Post-ERCP adverse events occurred in 5 (21.7%) of the patients in the air group and 8 (33.3%) of the patients in the contrast group. Among these, the rate of cholangitis was significantly lower in the air group (4.8% versus 29.2%, p = 0.048). In multivariate analysis, air cholangiography, technical success and a shorter procedure time were significantly associated with a lower incidence of post-ERCP cholangitis. Air cholangiography-assisted stenting can be a safe and effective method for endoscopic bilateral SIS placement of SEMS in patients with malignant hilar biliary obstruction.

  10. Stent Design Affects Femoropopliteal Artery Deformation.

    Science.gov (United States)

    MacTaggart, Jason; Poulson, William; Seas, Andreas; Deegan, Paul; Lomneth, Carol; Desyatova, Anastasia; Maleckis, Kaspars; Kamenskiy, Alexey

    2018-03-23

    Poor durability of femoropopliteal artery (FPA) stenting is multifactorial, and severe FPA deformations occurring with limb flexion are likely involved. Different stent designs result in dissimilar stent-artery interactions, but the degree of these effects in the FPA is insufficiently understood. To determine how different stent designs affect limb flexion-induced FPA deformations. Retrievable markers were deployed into n = 28 FPAs of lightly embalmed human cadavers. Bodies were perfused and CT images were acquired with limbs in the standing, walking, sitting, and gardening postures. Image analysis allowed measurement of baseline FPA foreshortening, bending, and twisting associated with each posture. Markers were retrieved and 7 different stents were deployed across the adductor hiatus in the same limbs. Markers were then redeployed in the stented FPAs, and limbs were reimaged. Baseline and stented FPA deformations were compared to determine the influence of each stent design. Proximal to the stent, Innova, Supera, and SmartFlex exacerbated foreshortening, SmartFlex exacerbated twisting, and SmartControl restricted bending of the FPA. Within the stent, all devices except Viabahn restricted foreshortening; Supera, SmartControl, and AbsolutePro restricted twisting; SmartFlex and Innova exacerbated twisting; and Supera and Viabahn restricted bending. Distal to the stents, all devices except AbsolutePro and Innova exacerbated foreshortening, and Viabahn, Supera, Zilver, and SmartControl exacerbated twisting. All stents except Supera were pinched in flexed limb postures. Peripheral self-expanding stents significantly affect limb flexion-induced FPA deformations, but in different ways. Although certain designs seem to accommodate some deformation modes, no device was able to match all FPA deformations.

  11. Heterogeneous Intravascular Ultrasound Findings of Stent Thrombosis

    OpenAIRE

    Morofuji, Toru; Inaba, Shinji; Aisu, Hiroe; Takahashi, Kayo; Saito, Makoto; Higashi, Haruhiko; Yoshii, Toyofumi; Sumimoto, Takumi

    2017-01-01

    Objective The underlying mechanisms of stent thrombosis are not completely understood. Methods We experienced 12 definite stent thrombosis cases (1 early, 1 late, and 10 very late) at our hospital from July 2011 to April 2016 and evaluated the possible causes of stent thrombosis by intravascular ultrasound (IVUS). Results Five different potential morphological causes of stent thrombosis (neoatherosclerosis, stent malapposition, stent fracture, edge dissection, and stent underexpansion) were d...

  12. Coronary In-Stent Restenosis: Assessment with Corrected Coronary Opacification Difference across Coronary Stents Measured with CT Angiography.

    Science.gov (United States)

    Gao, Yang; Lu, Bin; Hou, Zhi Hui; Yu, Fang Fang; Yin, Wei Hua; Wang, Zhi Qiang; Wu, Yong Jian; Mu, Chao Wei; Meinel, Felix G; McQuiston, Andrew D; Schoepf, U Joseph

    2015-05-01

    To determine whether changes in coronary opacification normalized to the aorta (corrected coronary opacification [CCO]) across stents can help identify in-stent restenosis (ISR) severity with use of invasive coronary angiography as the standard of reference. This study was approved by the institutional review board, and the requirement to obtain informed consent was waived. The authors retrospectively analyzed 106 patients (88 men, 18 women; mean age, 59.6 years ± 10.4; age range, 36-84 years) who had previously undergone stent implantation within 3 months of coronary computed tomographic (CT) angiography. Attenuation values in the coronary lumen were measured proximal and distal to the stents and normalized to the descending aorta. The CCO difference across the stent was compared with the severity of ISR. One-way analysis of variance least significant difference was used for comparison. A total of 141 stents were assessed. Seventy-six stents were normally patent, 18 had ISR of less than 50%, 28 had ISR of 50%-99%, and 19 were fully occluded. The median CCO differences in the four groups were 0.078, 0.163, 0.346, and 0.606, respectively. There was no significant difference between stents with an ISR of at least 50% and those with total occlusion (P = .056), although the other groups had significant differences at pairwise comparison (P stents smaller than 3 mm in diameter, the median CCO differences in the four groups were 0.086, 0.136, 0.390, and 0.471, respectively. The CCO differences across normal stents and stents with ISR of less than 50% were significantly less than those across stents with an ISR of at least 50% and those with total occlusion (P stents with no ISR and those with an ISR of less than 50% (P = .821) and between stents with an ISR of at least 50% and those with an ISR of 100% (P = .836). The CCO difference across coronary stents is related to ISR severity in obstructive ISR in stents smaller than 3 mm in diameter. © RSNA, 2014.

  13. Mechanical Properties of Metallic Stents: How Do These Properties Influence the Choice of Stent for Specific Lesions?

    International Nuclear Information System (INIS)

    Dyet, John F.; Watts, William G.; Ettles, Duncan F.; Nicholson, Anthony A.

    2000-01-01

    Purpose: To assess selected balloon-expandable and self-expanding stents for radial force, flexibility, radio-opacity, and trackability, and to relate these physical characteristics to potential indications for placement.Methods: Force-strain curves were plotted for each stent and the force required to produce 50% luminal narrowing was recorded. The ability of the stent to show elastic recoil following deformation was also noted. Flexibility was measured by bending the stents against a force transducer and recording the force required per degree of flexion. Radio-opacity was measured by comparing each stent against a standard aluminum step wedge. Trackability was measured by testing the ability of the stent on its delivery system to track over angles of 90 deg. and 60 deg. Results: The balloon-expandable stents showed greater radial strength and radio-opacity but, apart from the AVE Iliac Bridge stent, showed poorer flexibility and trackability. The self-expanding stents showed less radial force but were able to re-expand following deformity. They were generally more flexible and had better trackability but lower radio-opacity.Conclusion: There is no stent which exhibits all the ideal properties required and therefore the interventionist will need to keep a range of stents available if all lesions are to be addressed

  14. PulmoStent : In Vitro to In Vivo Evaluation of a Tissue Engineered Endobronchial Stent

    NARCIS (Netherlands)

    Thiebes, Anja Lena; Kelly, Nicola; Sweeney, Caoimhe A.; McGrath, Donnacha J.; Clauser, Johanna; Kurtenbach, Kathrin; Gesche, Valentine N.; Chen, Weiluan; Kok, Robbert Jan; Steinseifer, Ulrich; Bruzzi, Mark; O’Brien, Barry J.; McHugh, Peter E.; Jockenhoevel, Stefan; Cornelissen, Christian G.

    Currently, there is no optimal treatment available for end stage tumour patients with airway stenosis. The PulmoStent concept aims on overcoming current hurdles in airway stenting by combining a nitinol stent with a nutrient-permeable membrane, which prevents tumour ingrowth. Respiratory epithelial

  15. Stent migration after right ventricular outflow tract stenting in the severe cyanotic Tetralogy of Fallot case

    Directory of Open Access Journals (Sweden)

    Tamaki Hayashi

    2017-01-01

    Full Text Available We report our experience with a stent migration after right ventricle outflow tract stenting and converted to patent ductus arteriosus stenting in Tetralogy of Fallot (TOF with severe infundibular stenosis. Finally, the patient achieved to TOF repair, and the migrated stent was removed without any complication.

  16. Creation of individual ideally shaped stents using multi-slice CT: in vitro results from the semi-automatic virtual stent (SAVS) designer

    International Nuclear Information System (INIS)

    Hyodoh, Hideki; Katagiri, Yoshimi; Hyodoh, Kazusa; Akiba, Hidenari; Hareyama, Masato; Sakai, Toyohiko

    2005-01-01

    To plan stent-grafting for thoracic aortic aneurysm with complicated morphology, we created a virtual stent-grafting program [Semi Automatic Virtual Stent (SAVS) designer] using three-dimensional CT data. The usefulness of the SAVS designer was evaluated by measurement of transformed anatomical and straight stents. Curved model images (source, multi-planer reconstruction and volume rendering) were created, and a hollow virtual stent was produced by the SAVS designer. A straight Nitinol stent was transformed to match the curved configuration of the virtual stent. The accuracy of the anatomical stent was evaluated by experimental strain phantom studies in comparison with the straight stent. Mean separation length was 0 mm in the anatomical stent [22 mm outer diameter (OD)] and 5 mm in the straight stent (22 mm OD). The straight stent strain voltage was four times that of the anatomical stent at the stent end. The anatomical stent is useful because it fits the curved structure of the aorta and reduces the strain force compared to the straight stent. The SAVS designer can help to design and produce the anatomical stent. (orig.)

  17. Configuration affects parallel stent grafting results.

    Science.gov (United States)

    Tanious, Adam; Wooster, Mathew; Armstrong, Paul A; Zwiebel, Bruce; Grundy, Shane; Back, Martin R; Shames, Murray L

    2018-05-01

    A number of adjunctive "off-the-shelf" procedures have been described to treat complex aortic diseases. Our goal was to evaluate parallel stent graft configurations and to determine an optimal formula for these procedures. This is a retrospective review of all patients at a single medical center treated with parallel stent grafts from January 2010 to September 2015. Outcomes were evaluated on the basis of parallel graft orientation, type, and main body device. Primary end points included parallel stent graft compromise and overall endovascular aneurysm repair (EVAR) compromise. There were 78 patients treated with a total of 144 parallel stents for a variety of pathologic processes. There was a significant correlation between main body oversizing and snorkel compromise (P = .0195) and overall procedural complication (P = .0019) but not with endoleak rates. Patients were organized into the following oversizing groups for further analysis: 0% to 10%, 10% to 20%, and >20%. Those oversized into the 0% to 10% group had the highest rate of overall EVAR complication (73%; P = .0003). There were no significant correlations between any one particular configuration and overall procedural complication. There was also no significant correlation between total number of parallel stents employed and overall complication. Composite EVAR configuration had no significant correlation with individual snorkel compromise, endoleak, or overall EVAR or procedural complication. The configuration most prone to individual snorkel compromise and overall EVAR complication was a four-stent configuration with two stents in an antegrade position and two stents in a retrograde position (60% complication rate). The configuration most prone to endoleak was one or two stents in retrograde position (33% endoleak rate), followed by three stents in an all-antegrade position (25%). There was a significant correlation between individual stent configuration and stent compromise (P = .0385), with 31

  18. A novel self-expanding fully retrievable intracranial stent (SOLO): experience in nine procedures of stent-assisted aneurysm coil occlusion

    International Nuclear Information System (INIS)

    Liebig, Thomas; Henkes, Hans; Reinartz, Joerg; Miloslavski, Elina; Kuehne, Dietmar

    2006-01-01

    The endovascular treatment of large and broad-necked aneurysms may require the use of a remodelling balloon or a stent system to achieve proper occlusion while maintaining the patency of the parent vessel. With the advent of self-expanding stents that can be delivered through a microcatheter, this kind of treatment has improved and problems with the previously used balloon expandable stents have largely been overcome. However, rigidity, insufficient trackability, and limited or non-existent retrievability may still restrict the application of self-expanding stents in some situations. Recently, a stent system with a new and different design has been introduced. This stent is highly flexible, fully retrievable, and can be delivered through a standard 0.021-inch microcatheter without a wire. We describe the first nine cases of stent-assisted coil occlusion of intracranial aneurysms with the use of this stent system. Between May and June of 2004, nine patients with large or broad-necked aneurysms were treated in two endovascular centres. The anatomy of the aneurysms and parent vessels, technical details of the procedure, performance of the stent system, and follow-up results were evaluated. In all procedures, the SOLO stent could be introduced without difficulty, in one procedure after positioning of a different self-expanding stent system had failed due to vessel tortuosity. Overlapping stents were placed in one patient and stent retrieval or repositioning was successfully performed in two procedures. There was no interference or limitation of subsequent coil occlusion after stenting. With regard to the stent, immediate postprocedure and follow-up angiograms were unremarkable in terms of thromboembolic events and signs of intimal hyperplasia. From our experience, we conclude that the SOLO stent shows satisfactory performance overall. Its unique design gives the stent properties that may help overcome some of the difficulties experienced with other self

  19. Reintervention for stent occlusion after bilateral self-expandable metallic stent placement for malignant hilar biliary obstruction.

    Science.gov (United States)

    Inoue, Tadahisa; Naitoh, Itaru; Okumura, Fumihiro; Ozeki, Takanori; Anbe, Kaiki; Iwasaki, Hiroyasu; Nishie, Hirotada; Mizushima, Takashi; Sano, Hitoshi; Nakazawa, Takahiro; Yoneda, Masashi; Joh, Takashi

    2016-11-01

    Endoscopic reintervention for stent occlusions following bilateral self-expandable metallic stent (SEMS) placement for malignant hilar biliary obstruction (MHBO) is challenging, and time to recurrent biliary obstruction (RBO) of the revisionary stent remains unclear. We aimed to clarify a suitable reintervention method for stent occlusions following bilateral SEMS placement for MHBO. Between 2002 and 2014, 52 consecutive patients with MHBO who underwent endoscopic reintervention for stent occlusion after bilateral SEMS placement were enrolled at two university hospitals and one tertiary care referral center. We retrospectively evaluated the technical and functional success rates of the reinterventions, and the time to RBO of the revisionary stents. Technical and functional success rates of the reinterventions were 92% (48/52) and 90% (43/48), respectively. Univariate analysis did not determine any significant predictive factors for technical and functional failures. Median time to RBO of the revisionary stents was 68 days. Median time to RBO was significantly longer for revisionary SEMS placement than for plastic stent placement (131 days vs 47 days, respectively; log-rank test, P = 0.005). Revisionary SEMS placement was the only independent factor that was significantly associated with a longer time to RBO of the revisionary stent in the multivariate Cox proportional hazards analysis (hazard ratio 0.37; 95% confidence interval 0.14-0.95; P = 0.039). Revisionary SEMS placement is a suitable endoscopic reintervention method for stent occlusion following bilateral SEMS placement from the perspective of time to RBO of the revisionary stent. © 2016 Japan Gastroenterological Endoscopy Society.

  20. A comparison of clinical efficacy between covered stent-grafts and bare stents in transjuglar in-trahepatic portosystemic shunt

    International Nuclear Information System (INIS)

    Jiang Yongbin; Zhang Xitong; Zhang Wei; Xia Yonghui; Liang Songnian; Xu Ke

    2010-01-01

    Objective: To compare the clinical efficacy between covered stent and uncovered stent in transjuglar in-trahepatic portosystemic shunt (TIPS). Methods: Thirty patients with liver cirrhosis (portal hypertension), who received TIPS, were retrospectively studied. All patients were divided into two groups covered-stent group (n=20) and uncovered-stent group (n=10). For each patient, portal pressure was measured before and after operation, and the patency of shunt was evaluated by color Doppler ultrasound after operation. The mortality, recurrent bleeding rate and incidence of hepatic encephalopathy were analyzed by Fisher exact probability test. Results: The TIPS treatment was successful in all patients, the portal pressure in the covered-stent group reduced from (3.78 ± 0.50)kPa to (2.13 ± 0.44) kPa and that of the uncovered-stent group reduced from (3.67 ± 0.48)kPA TO (2.13 ± 0.35)kPa. Twenty-six cases were postoperatively followed-up (17 cases in covered-stent group, 9 cases in uncovered-stent group). the follow-up period varied from 7 days to 62 months (median follow-up period was 23 months). Thirteen patients died of upper gastrointestinal bleeding and hepatic failure. The difference of mortality between covered-stent group (8/17) and uncovered-stent group (5/17) and the uncovered-stent group (3/9) was not different too (P>0.05). The incidence of hepatic encephalopathy in the covered-stent group (4/17) was not different from that of the uncovered-stent group (2/9) (P>0.05). The patency rates of 6 months and 12 months reached 100% in the covered-stent group, which were higher than those in the uncovered-stent group 77.8% (7/9) and 55.6%(5/9) (P<0.05). Conclusions: The patency rate of shunt at 12 months after TIPS was higher in the covered-stent group than the uncovered-stent group, while the mortality, recurrent bleeding rate and incidence of hepatic encephalopathy were not significantly different between the two groups. (authors)

  1. Comparison of closed-cell and hybrid-cell stent designs in carotid artery stenting: clinical and procedural outcomes

    Directory of Open Access Journals (Sweden)

    Ersan TatlI

    2017-05-01

    Full Text Available Introduction: Carotid artery stenting (CAS is a promising alternative to surgery in high-risk patients. However, the impact of stent cell design on outcomes in CAS is a matter of continued debate. Aim : To compare the periprocedural and clinical outcomes of different stent designs for CAS with distal protection devices. Material and methods : All CAS procedures with both closed- and hybrid-cell stents performed at our institution between February 2010 and December 2015 were analyzed retrospectively. Adverse events were defined as death, major stroke, minor stroke, transient ischemic attack and myocardial infarction. Periprocedural and 30-day adverse events and internal carotid artery (ICA vasospasm rates were compared between the closed-cell and hybrid-cell stent groups. Results : The study included 234 patients comprising 146 patients with a closed-cell stent (Xact stent, Abbott Vascular (mean age: 68.5 ±8.6; 67.1% male and 88 patients with a hybrid-cell stent (Cristallo Ideale, Medtronic (mean age: 67.2 ±12.8; 68.2% male. There was no significant difference between the groups with respect to periprocedural or 30-day adverse event rates. While there was no difference in terms of tortuosity index between the groups, there was a higher procedural ICA vasospasm rate in the closed-cell stent group (35 patients, 23% compared with the hybrid-cell stent group (10 patients, 11% (p = 0.017. Conclusions : The results of this study showed no significant difference in the clinical adverse event rates after CAS between the closed-cell stent group and the hybrid-cell stent group. However, procedural ICA vasospasm was more common in the closed-cell stent group.

  2. The forgotten ureteric JJ stent and its prevention: a prospective audit of the value of a ureteric stent logbook.

    Science.gov (United States)

    Thomas, A Z; Casey, R G; Grainger, R; McDermott, T; Flynn, R; Thornhill, J A

    2007-01-01

    Temporary ureteric stent insertion is an integral part of modern endo-urological practice. Delayed stent removal or forgotten stents are associated with increased patient morbidity and complications which are often difficult to manage. We prospectively audited our ureteric stent insertion and removal logbook system to determine the value and effectiveness of our stent follow-up. Over a 1-year period, 210 ureteric stents were inserted in our urological unit. Of these, 47 (22.4%) patients were unaccounted as having their stents removed within the stent logbooks. One patient was lost to follow-up and re-presented with stent encrustation 10 months later. Our results in this audit suggest that our system of ureteric stent follow-up is not effective. We have now introduced a new system that we feel is a safer and a satisfactory alternative to the stent logbooks. This includes a patient education leaflet and removal date scheduling prior to discharge from hospital.

  3. ¿Trombosis muy tardía de stent coronario? Más allá de la angiografía

    Directory of Open Access Journals (Sweden)

    Teresa Alvarado

    2016-03-01

    Full Text Available Varón de 60 años con antecedentes de hipertensión arterial, dislipemia y cardiopatía isquémica, esta última con debut 8 años antes por angina inestable; en ese momento se realizó coronariografía que mostró enfermedad de la coronaria derecha (CD: un vaso ectásico, con importante remodelado positivo y lesiones graves en su segmento distal, y en el proximal de la rama posterolateral. Se trató mediante implante de dos stents no farmacoactivos. Desde entonces el paciente permaneció asintomático, con buen control de los factores de riesgo cardiovascular.

  4. Metallic stents provide better QOL than plastic stents in patients with stricture of unresectable advanced esophageal cancer

    International Nuclear Information System (INIS)

    Ohta, Kazuki; Nagahara, Akihito; Iijima, Katsuyori

    2006-01-01

    The aim of this study was to elucidate the utility and safety of treatment with esophageal stents (plastic and metallic stents) for unresectable advanced esophageal cancer. Between 1992 and 2002, 14 cases of unresectable advanced esophageal cancer were treated with esophageal stents (the plastic stent group, 7 cases; and the metallic stent group, 7 cases). Of these, 10 cases had a history of chemotherapy and or radiotherapy. An improvement in oral intake and performance status (PS), survival time, periods at home, and adverse events were compared between the two groups. After stenting, oral intake and PS were significantly improved in the metallic stent group. Follow-up at home was possible in 71.4%. There was no significant difference in survival or duration of time at home between the two groups. All adverse events were controllable and there was no difference between the two groups. Stenting not only improved oral intake and PS but also allowed a stay at home, resulting in a marked improvement in patients' quality of life (QOL). Stenting was performed safely even in cases with a history of radiotherapy. There was no difference in survival, ratios of staying at home, and safety between the two groups, but QOL was significantly improved in the metallic stent group. These outcomes indicate that placement of metallic stents should be actively considered to treat stricture due to advanced esophageal cancer. (author)

  5. Clinical experience in coronary stenting with the Vivant Z Stent.

    Science.gov (United States)

    Chee, K H; Siaw, F S; Chan, C G; Chong, W P; Imran, Z A; Haizal, H K; Azman, W; Tan, K H

    2005-06-01

    This single centre study was designed to demonstrate feasibility, safety and efficacy of the Vivant Z stent (PFM AG, Cologne, Germany). Patients with de novo lesion were recruited. Coronary angioplasty was performed with either direct stenting or after balloon predilatation. Repeated angiogram was performed 6 months later or earlier if clinically indicated. Between January to June 2003, a total of 50 patients were recruited (mean age 55.8 +/- 9 years). A total of 52 lesions were stented successfully. Mean reference diameter was 2.77 mm (+/-0.59 SD, range 2.05-4.39 mm) with mean target lesion stenosis of 65.5% (+/-11.6 SD, range 50.1-93.3%). Forty-six lesions (88.5%) were American College of Cardiologist/American Heart Association class B/C types. Direct stenting was performed in 18 (34.6%) lesions. Mean stent diameter was 3.18 mm (+/-0.41 SD, range 2.5-4 mm), and mean stent length was 14.86 mm (+/-2.72 SD, range 9-18 mm). The procedure was complicated in only one case which involved the loss of side branch with no clinical sequelae. All treated lesions achieved Thrombolysis In Myocardial Infarction 3 flow. Mean residual diameter stenosis was 12.2% (+/-7.55 SD, range 0-22.6%) with acute gain of 1.72 mm (+/-0.50 SD, range 0.5-2.8). At 6 months, there was no major adverse cardiovascular event. Repeated angiography after 6 months showed a restenosis rate of 17% (defined as >50% diameter restenosis). Mean late loss was 0.96 mm (+/-0.48 SD) with loss index of 0.61 (+/-0.38 SD). The restenosis rate of those lesions less than 3.0 mm in diameter was 22.2% compared with 6.25% in those lesions more than 3.0 mm in diameter. The Vivant Z stent was shown to be safe and efficacious with low restenosis rate in de novo coronary artery lesion.

  6. Comparison of Recanalization and In-Stent Stenosis Between the Low-Profile Visualized Intraluminal Support Stent and Enterprise Stent-Assisted Coiling for 254 Intracranial Aneurysms.

    Science.gov (United States)

    Feng, Xin; Qian, Zenghui; Liu, Peng; Zhang, Baorui; Wang, Luyao; Guo, Erkang; Wen, Xiaolong; Xu, Wenjuan; Jiang, Chuhan; Wu, Zhongxue; Li, Youxiang; Liu, Aihua

    2018-01-01

    To compare the rates of recanalization and in-stent stenosis between the Enterprise (EP) and low-profile visualized intraluminal support (LVIS) stent deployments for intracranial aneurysms (IAs), and the factors associated therein. Between June 2014 and July 2016, 142 patients with a total of 161 IAs were treated by LVIS stent-assisted coiling and 111 patients with a total of 142 IAs were treated by EP stent-assisted coiling at our institution. Procedure-related complications, angiographic follow-up results, and clinical outcomes were analyzed statistically. The rates of initially complete and near-complete IA occlusion immediately after the procedure were similar in the LVIS and EP groups (94.3% vs. 89.9%; P = 0.275). On follow-up, complete and near-complete occlusion rates and recanalization rates were also similar in the 2 groups (96.6% vs. 92.1%; P =0.330 and 8.0% vs. 13.5%; P = 0.245, respectively). On logistic regression analysis, a higher size ratio (SR) was significantly associated with the recanalization of aneurysms in the EP group, but not in the LVIS group. The rate of moderate to severe in-stent stenosis was lower in the LVIS group (10.2%) than in the EP group (16.8%), but the difference was not statistically significant (P = 0.198). Our data show acceptable rates of complete and near-complete occlusion with both the LVIS and EP stents. LVIS stents were associated with lower rates of recanalization and in-stent stenosis, but the difference was not significant. Higher SR (≥2) was a significant predictor of recanalization in IAs treated with EP stents, but not in those treated with LVIS stents. Copyright © 2017. Published by Elsevier Inc.

  7. Influence of a pressure gradient distal to implanted bare-metal stent on in-stent restenosis after percutaneous coronary intervention

    DEFF Research Database (Denmark)

    Jensen, Lisette Okkels; Thayssen, Per; Thuesen, Leif

    2007-01-01

    pullback recording in the entire length of the artery. METHODS AND RESULTS: In 98 patients with angina pectoris, 1 de novo coronary lesion was treated with a bare-metal stent. After stent implantation, pressure wire measurements (P(d)=mean hyperemic coronary pressure and P(a)=mean aortic pressure) were......-stent restenosis after 9 months. CONCLUSIONS: A residual abnormal P(d)/P(a) distal to a bare-metal stent was an independent predictor of in-stent restenosis after implantation of a coronary bare-metal stent. Udgivelsesdato: 2007-Dec-11......BACKGROUND: Fractional flow reserve predicts cardiac events after coronary stent implantation. The aim of the present study was to assess the 9-month angiographic in-stent restenosis rate in the setting of optimal stenting and a persisting gradient distal to the stent as assessed by a pressure wire...

  8. Study on the application of big cup membranate stent on restenosis after stenting for carcinoma of esophago cardia

    International Nuclear Information System (INIS)

    Wang Xiuping; Yao Zhongqiang; Liu Jian; Zhang Yan

    2007-01-01

    Objective: To evaluate the clinical value of self-designed big cup membranate stent on restenosis after stenting for carcinoma of esophago-cardia. Methods: 12 cases of restenosis after stenting for carcinoma of esophago-cardia were involved in the study. Self-designed big cup membranate stent made by Nanjing Weichuang Company (the length of the cup was 3.5 cm)was placed into the constricted stent under guidance of fluoroscopy. Clinical effect, restenosis, and complications were observed during followed up. Results: All the 12 cases of big cup membranat stent placement went along smoothly without indigitation of the cup of the stent. Follow-up of 1.5-8 months showed that 2 cases developed severe restenosis on the big cup of the stem, resulting in third grade difficult deglutition. Among them, one occurred 1 month after stenting, caused by hyperplasia of large amount of granulation tissue; another occurred 6 months after stenting, caused by growth of tumor tissue. 3 cases developed mild to moderate restenosis, 2.3-7 months (mean: 4.6 months) after stenting, with result of first grade difficult deglutition. The remaining 7 cases (mean 5.6 months follow-up) did not have difficulty during deglutition. Conclusions: Application of big cup membranate stent on restenosis after stenting for carcinoma of esophago-cardia can effectively prevent the stent from moving downwards and thus lower down the rate of restenosis, and postpone the occurrence of restenosis. (authors)

  9. Plastic strains during stent deployment have a critical influence on the rate of corrosion in absorbable magnesium stents.

    Science.gov (United States)

    Galvin, Emmet; Cummins, Christy; Yoshihara, Shoichiro; Mac Donald, Bryan J; Lally, Caitríona

    2017-08-01

    Magnesium stents are a promising candidate in the emerging field of absorbable metallic stents (AMSs). In this study, the mechanical and corrosion performance of dog-bone specimens and a specific stent design of a magnesium alloy, WE43, are assessed experimentally in terms of their corrosion behaviour and mechanical integrity. It is shown that plastic strains that are induced in the struts of the stent during stent deployment have a critical influence in directing subsequent corrosion behaviour within the material. In addition, the deployment and scaffolding characteristics of the magnesium stent are elucidated and contrasted with those of a commercial stainless steel stent. The magnesium stent is found to support higher levels of cyclic strain amplitude than the stainless steel stent, even prior to degradation, and this may play a role in reducing in-stent restenosis. This study provides new insights into the experimental performance of a current AMS design and material whilst demonstrating the critical influence of plastic strain on the corrosion performance and scaffolding ability of an AMS.

  10. Experimental study of the preventive effect of 1'03Pd stent on in-stent restenosis in rabbit iliac artery

    International Nuclear Information System (INIS)

    Luo Quanyong; Chen Libo; Yuan Zhibin; Lu Hankui; Zhu Ruisen

    2003-01-01

    Objective: To investigate the ability of γ-emitting 103 Pd radioactive stent implantation for preventing in-stent restenosis in iliac artery of rabbits. Methods: Twenty New Zealand white rabbits were divided into six groups on the basis of radioactivity loading [2.22 (n=3), 5.55 (n=4), 9.25 (n=4), 14.8 (n=3), 22.2 (n=3), 33.3 MBq (n=3)]. 103 Pd stent was implanted in one of the two iliac arteries of each rabbit and nonradioactive stent in the contralateral artery. The rabbits were fed with high fat diet. Treatment efficiency was assessed by angiography and quantitative histomorphometry of the stented iliac segments 28 d after the implantation. Results: Quantitative histomorphometry analysis indicated that 103 Pd stents induced a significant reduction in neointimal area and the percentage of stenosis within radioactive stents was lower compared with that in the control stents. Nevertheless, the suppression of neointima formation by 103 Pd stent implantation was not in a dose-dependent manner. Conclusions: Low-dose intravascular brachytherapy via a γ-particle-emitting 103 Pd radioactive stent potently inhibits neointimal hyperplasia and prevents the in-stent restenosis in rabbit iliac artery. 103 Pd stent implantation probably can be employed as a novel means to prevent in-stent restenosis

  11. Stent Thrombosis is the Primary Cause of ST-Segment Elevation Myocardial Infarction following Coronary Stent Implantation

    DEFF Research Database (Denmark)

    Kristensen, Søren Lund; Galløe, Anders M; Thuesen, Leif

    2014-01-01

    Background: The widespread use of coronary stents has exposed a growing population to the risk of stent thrombosis, but the importance in terms of risk of ST-segment elevation myocardial infarctions (STEMIs) remains unclear. Methods: We studied five years follow-up data for 2,098 all-comer patients...... treated with coronary stents in the randomized SORT OUT II trial (mean age 63.6 yrs. 74.8% men). Patients who following stent implantation were readmitted with STEMI were included and each patient was categorized ranging from definite-to ruled-out stent thrombosis according to the Academic Research...... Consortium definitions. Multivariate logistic regression was performed on selected covariates to assess odds ratios (ORs) for definite stent thrombosis. Results: 85 patients (4.1%), mean age 62.7 years, 77.1% men, were admitted with a total of 96 STEMIs, of whom 60 (62.5%) had definite stent thrombosis...

  12. Impact of stent length on clinical outcomes of first-generation and new-generation drug-eluting stents.

    Science.gov (United States)

    Konishi, Hirokazu; Miyauchi, Katsumi; Dohi, Tomotaka; Tsuboi, Shuta; Ogita, Manabu; Naito, Ryo; Kasai, Takatoshi; Tamura, Hiroshi; Okazaki, Shinya; Isoda, Kikuo; Daida, Hiroyuki

    2016-04-01

    The aim of this study is to compare first- and new-generation drug-eluting stents (DESs) which are implanted in long lesion. Stent length is known to be a predictor of adverse events after percutaneous coronary intervention (PCI), even with the first-generation DESs. The introduction of new-generation DESs has reduced the rates of adverse clinical events. However, the impact of stent length on long-term clinical outcomes is not well known. A total of 1181 consecutive patients who underwent PCI using either a first-generation DES (n = 885) or a new-generation DES (n = 296) between 2004 and 2011 were investigated. In each of the stent groups, the patients were divided into two groups by stent length (>32 and ≤32 mm) and compared. During the follow-up period, the incidence of major adverse cardiac events (MACEs) was significantly higher for patients with long stents implanted than with short stents (P stent groups in the new-generation DES group (P = 0.24; log-rank test). On multivariate Cox regression analysis, stent length was not associated with adverse events in the new-generation DES groups [hazard ratio (HR) 0.87; 95 % confidence interval (95 % CI) 0.71-1.04; P = 0.14]. Implanted stent length was significantly associated with a higher risk of MACEs in patients who received first-generation DESs, but not in patients who received the new-generation DESs.

  13. Evaluation of a novel stent technology: the Genous EPC capturing stent

    NARCIS (Netherlands)

    Klomp, M.

    2012-01-01

    Tegenwoordig gebruiken ziekenhuizen een nieuwe stent bij dotterbehandelingen van kransslagadervernauwingen. Deze Genous-stent heeft een laag met antistoffen waardoor het behandelde bloedvat snel bedekt raakt met lichaamseigen cellen. Zo wordt tegengegaan dat er opnieuw een vernauwing optreedt of dat

  14. Effect of Covered Metallic Stents Compared With Plastic Stents on Benign Biliary Stricture Resolution

    Science.gov (United States)

    Coté, Gregory A.; Slivka, Adam; Tarnasky, Paul; Mullady, Daniel K.; Elmunzer, B. Joseph; Elta, Grace; Fogel, Evan; Lehman, Glen; McHenry, Lee; Romagnuolo, Joseph; Menon, Shyam; Siddiqui, Uzma D.; Watkins, James; Lynch, Sheryl; Denski, Cheryl; Xu, Huiping; Sherman, Stuart

    2017-01-01

    IMPORTANCE Endoscopic placement of multiple plastic stents in parallel is the first-line treatment for most benign biliary strictures; it is possible that fully covered, self-expandable metallic stents (cSEMS) may require fewer endoscopic retrograde cholangiopancreatography procedures (ERCPs) to achieve resolution. OBJECTIVE To assess whether use of cSEMS is noninferior to plastic stents with respect to stricture resolution. DESIGN, SETTING, AND PARTICIPANTS Multicenter (8 endoscopic referral centers), open-label, parallel, randomized clinical trial involving patients with treatment-naive, benign biliary strictures (N = 112) due to orthotopic liver transplant (n = 73), chronic pancreatitis (n = 35), or postoperative injury (n = 4), who were enrolled between April 2011 and September 2014 (with follow-up ending October 2015). Patients with a bile duct diameter less than 6 mm and those with an intact gallbladder in whom the cystic duct would be overlapped by a cSEMS were excluded. INTERVENTIONS Patients (N = 112) were randomized to receive multiple plastic stents or a single cSEMS, stratified by stricture etiology and with endoscopic reassessment for resolution every 3 months (plastic stents) or every 6 months (cSEMS). Patients were followed up for 12 months after stricture resolution to assess for recurrence. MAIN OUTCOMES AND MEASURES Primary outcome was stricture resolution after no more than 12 months of endoscopic therapy. The sample size was estimated based on the noninferiority of cSEMS to plastic stents, with a noninferiority margin of −15%. RESULTS There were 55 patients in the plastic stent group (mean [SD] age, 57 [11] years; 17 women [31%]) and 57 patients in the cSEMS group (mean [SD] age, 55 [10] years; 19 women [33%]). Compared with plastic stents (41/48, 85.4%), the cSEMS resolution rate was 50 of 54 patients (92.6%), with a rate difference of 7.2% (1-sided 95% CI, −3.0% to ∞; P stents was rejected. The mean number of ERCPs to achieve resolution

  15. Stent thrombosis, myocardial infarction, and death after drug-eluting and bare-metal stent coronary interventions

    DEFF Research Database (Denmark)

    Jensen, Lisette Okkels; Maeng, Michael; Kaltoft, Anne

    2007-01-01

    OBJECTIVES: The aim of the study was to examine outcomes subsequent to implantation of drug-eluting stents (DES) and bare-metal stents (BMS). BACKGROUND: Use of DES might be associated with increased risk of stent thrombosis (ST), myocardial infarction (MI), and death. METHODS: From January 2002...... through June 2005, data from all percutaneous coronary interventions in western Denmark were prospectively recorded in the Western Denmark Heart Registry; 12,395 consecutive patients (17,152 lesions) treated with stent implantation were followed for 15 months. Data on death and MI were ascertained from...... within 15 months after implantation of DES seems unlikely to outweigh the benefit of these stents. Udgivelsesdato: 2007-Jul-31...

  16. Stent implantation into the tracheo-bronchial system in rabbits: histopathologic sequelae in bare metal vs. drug-eluting stents.

    Science.gov (United States)

    Sigler, Matthias; Klötzer, Julia; Quentin, Thomas; Paul, Thomas; Möller, Oliver

    2015-12-01

    Stent implantation into the tracheo-bronchial system may be life-saving in selected pediatric patients with otherwise intractable stenosis of the upper airways. Following implantation, significant tissue proliferation may occur, requiring re-interventions. We sought to evaluate the effect of immunosuppressive coating of the stents on the extent of tissue proliferation in an animal model. Bare metal and sirolimus-coated stents (Bx Sonic and Cypher Select, Johnson & Johnson, Cordis) were implanted into non-stenotic lower airways of New Zealand white rabbits (weight 3.1 to 4.8 kg). Three stents with sirolimus coating and six bare metal stents could be analyzed by means of histology and immunohistochemistry 12 months after implantation. On a macroscopic evaluation, all stents were partially covered with a considerable amount of whitish tissue. Histologically, these proliferations contained fiber-rich connective tissue and some fibromuscular cells without significant differences between both stent types. The superficial tissue layer was formed by typical respiratory epithelium and polygonal cells. Abundant lymphocyte infiltrations and moderate granulocyte infiltrations were found in both groups correspondingly, whereas foreign-body reaction was more pronounced around sirolimus-eluting stents. After stent implantation in the tracheo-bronchial system of rabbits, we found tissue reactions comparable to those seen after stent implantation into the vascular system. There was no difference between coated and uncoated stents with regard to quality and quantity of tissue proliferation. We found, however, a significantly different inflammatory reaction with a more pronounced foreign-body reaction in sirolimus-coated stents. In our small series, drug-eluting stents did not exhibit any benefit over bare metal stents in an experimental setting.

  17. One Year Outcomes of 101 BeGraft Stent Grafts used as Bridging Stents in Fenestrated Endovascular Repairs.

    Science.gov (United States)

    Spear, Rafaelle; Sobocinski, Jonathan; Hertault, Adrien; Delloye, Matthieu; Azzauiu, Richard; Fabre, Dominique; Haulon, Stéphan

    2018-04-01

    To evaluate the outcomes of the second generation BeGraft balloon expandable covered stent Graft System (Bentley InnoMed, Hechingen, Germany) implanted as bridging stent grafts during fenestrated endovascular aortic repair (FEVAR) of complex aneurysms. This was a single centre prospective study including all consecutive patients treated by FEVAR performed with second generation BeGraft stent grafts as bridging stents. Demographics of patients, diameter and length of the bridging stent grafts, technical success, re-interventions, occlusions, post-operative events, and imaging (Cone Beam CT and/or CT scan, and contrast enhanced ultrasound) were prospectively collected in an electronic database. Duplex ultrasound was performed before discharge and at 6 month follow-up. At 1 year, patients were evaluated clinically and by imaging (CT and ultrasound). Between November 2015 and September 2016, 39 consecutive patients (one woman) were treated with custom made fenestrated endografts (2-5 fenestrations) for complex aneurysms or type 1 endoleak after EVAR, using a variety of bridging stents including the BeGraft. All 101 BeGraft stent grafts were successfully delivered and deployed. There was no in hospital mortality. Early fenestration patency rate was 99% (96/97); the sole target vessel post-operative occlusion was secondary to a dissection of the renal artery distal to the stent. Complementary stenting was unsuccessful in recovering renal artery patency; bilateral renal stent occlusion was observed in the same patient on a CT scan performed 2 months after the procedure. He required post-operative dialysis. No additional renal impairment was observed. During follow-up (median 13 months [11-15]), all fenestrations stented with BeGraft stent grafts remained patent (95/97, 98%). One type 1b endoleak was detected and treated (2.6%). BeGraft stent grafts used as bridging stents during FEVAR are associated with favourable outcomes at 1 year follow-up. Long-term follow-up is

  18. Tracheal obstruction caused by an expandable metallic stent: a case of successful removal of the stent.

    Science.gov (United States)

    Okuyama, Hiroomi; Kubota, Akio; Kawahara, Hisayoshi; Oue, Takaharu; Nose, Satoko; Ihara, Toshiyuki

    2005-07-01

    We report a case of tracheal obstruction caused by an expandable metallic stent. A 3-month-old girl with severe tracheomalacia had a placement of a Palmaz stent. At 3 years of age, she developed progressive dyspnea. The CT scan showed tracheal obstruction caused by granulation tissue over the stent. At operation, the stent was found to have penetrated the posterior tracheal wall. Under partial cardiopulmonary bypass, the stent was removed along with the membranous wall of the trachea, and the trachea was reconstructed using slide tracheoplasty. Tracheal obstruction is one of the serious complications caused by an expandable metallic stent. Direct open approach to the trachea under cardiopulmonary bypass is thought to be a safe way to manage this problem.

  19. Prospective Evaluation of Two iStent® Trabecular Stents, One iStent Supra® Suprachoroidal Stent, and Postoperative Prostaglandin in Refractory Glaucoma: 4-year Outcomes.

    Science.gov (United States)

    Myers, Jonathan S; Masood, Imran; Hornbeak, Dana M; Belda, Jose I; Auffarth, Gerd; Jünemann, Anselm; Giamporcaro, Jane Ellen; Martinez-de-la-Casa, Jose M; Ahmed, Iqbal Ike K; Voskanyan, Lilit; Katz, L Jay

    2018-03-01

    This study evaluates long-term outcomes of two trabecular micro-bypass stents, one suprachoroidal stent, and postoperative prostaglandin in eyes with refractory open angle glaucoma (OAG). Prospective ongoing 5-year study of 80 eligible subjects (70 with 4-year follow-up) with OAG and IOP ≥ 18 mmHg after prior trabeculectomy and while taking 1-3 glaucoma medications. Subjects received two iStent ® trabecular micro-bypass stents, one iStent Supra ® suprachoroidal stent, and postoperative travoprost. Postoperative IOP was measured with medication and annually following medication washouts. Performance was measured by the proportion of eyes with ≥ 20% IOP reduction on one medication (the protocol-specified prostaglandin) versus preoperative medicated IOP (primary outcome); and the proportion of eyes with postoperative IOP ≤ 15 and ≤ 18 mmHg on one medication (secondary outcome). Additional clinical and safety data included medications, visual field, pachymetry, gonioscopy, adverse events, visual acuity, and slit-lamp and fundus examinations. Preoperatively, mean medicated IOP was 22.0 ± 3.1 mmHg on 1.2 ± 0.4 medications, and mean unmedicated IOP was 26.4 ± 2.4 mmHg. Postoperatively, among eyes without later cataract surgery, mean medicated IOP at all visits through 48 months was ≤ 13.7 mmHg (≥ 37% reduction), and annual unmedicated IOP was ≤ 18.4 mmHg (reductions of ≥ 30% vs. preoperative unmedicated IOP and ≥ 16% vs. preoperative medicated IOP). At all postoperative visits among eyes without additional surgery or medication, ≥ 91% of eyes had ≥ 20% IOP reduction on one medication versus preoperative medicated IOP. At month 48, 97 and 98% of eyes achieved IOP ≤ 15 and ≤ 18 mmHg, respectively, on one medication. Six eyes required additional medication, no eyes required additional glaucoma surgery, and safety measurements were favorable throughout follow-up. IOP control was achieved safely with two

  20. [Coronary stents: 30 years of medical progress].

    Science.gov (United States)

    Silvain, Johanne; Cayla, Guillaume; Collet, Jean-Philippe; Fargeot, Catherine; Montalescot, Gilles

    2014-03-01

    The history of interventional cardiology has been marked by several technologic revolutions since the late 1970s. The first key step was the use of inflatable balloon angioplasty as an alternative to CABG surgery for coronary revascularization, followed by intracoronary delivery of bare metal stent (BMS) and drug eluting stents (DES) to drastically reduce intracoronary restenosis observed with BMS. Improved stents platforms and polymers (absorbable or biocompatible) led to a dramatic reduction in the rate of late stent thrombosis. Self-expanding stents are now available to improve stent a position especially in acute myocardial infarction. The emergence of new fully bioabsorbable stents that can be combined with antiproliferative drugs is the ongoing revolution. A new generation of stents is continuously improving and likely to become the ideal stent for coronary revascularization in the near future. © 2014 médecine/sciences – Inserm.

  1. Safety and efficacy of everolimus-eluting stents for bare-metal in-stent restenosis

    Energy Technology Data Exchange (ETDEWEB)

    Ota, Hideaki [Division of Interventional Cardiology, MedStar Washington Hospital Center, Washington, DC 20010 (United States); Mahmoudi, Michael [University of Surrey, Guildford Road, Surrey, GU2-7XH (United Kingdom); Torguson, Rebecca; Satler, Lowell F.; Suddath, William O.; Pichard, Augusto D. [Division of Interventional Cardiology, MedStar Washington Hospital Center, Washington, DC 20010 (United States); Waksman, Ron, E-mail: ron.waksman@medstar.net [Division of Interventional Cardiology, MedStar Washington Hospital Center, Washington, DC 20010 (United States)

    2015-04-15

    Objective: The aim of this study was to compare the safety and efficacy of the everolimus-eluting stents (EES) with the paclitaxel-eluting stent (PES) and sirolimus-eluting stent (SES) for the treatment of bare-metal in-stent restenosis. Background: The optimal treatment for bare-metal in-stent restenosis remains controversial. Methods: The study cohort comprised 322 consecutive patients (543 lesions) who presented with bare-metal in-stent restenosis to our institution and underwent coronary artery stent implantation with EES (114 patients; 181 lesions), PES (65 patients; 116 lesions) and SES (143 patients; 246 lesions). The analyzed clinical parameters were the 1-year rates of death, Q-wave myocardial infarction (MI), target lesion revascularization (TLR), target vessel revascularization (TVR), definite stent thrombosis (ST) and major adverse cardiac events (MACE) defined as the composite of death, MI, or TLR at 1-year. Results: The three groups were well matched for the conventional risk factors except for age and chronic kidney disease. The 1-year analyzed clinical parameters were similar in the three groups: death (EES = 3.5%, PES = 4.6%, SES = 4.2%; p = 0.94), MI (EES = 3.5%, PES = 6.3%, SES = 2.1%; p = 0.31), TLR (EES = 9.8%, PES = 9.5%, SES = 5.7%; p = 0.42), TVR (EES = 14.3%, PES = 11.1%, SES = 11.3%; p = 0.74), definite ST (EES = 0.9%, PES = 3.1%, SES = 3.5%; p = 0.38) and MACE (EES = 14.0%, PES = 15.4%, SES = 10.5%; p = 0.54). Male gender (hazard ratio = 0.47; 95% confidence interval = 0.25–0.88) and number of treated lesions (hazard ratio = 1.47; 95% confidence interval = 1.06–2.05) were found to be independent predictors of MACE. Conclusion: The results of the present study indicate that EES may provide similar safety and efficacy as first generation DES for the treatment of patients presenting with bare-metal in-stent restenosis.

  2. Introduction of a high-throughput double-stent animal model for the evaluation of biodegradable vascular stents.

    Science.gov (United States)

    Borinski, Mauricio; Flege, Christian; Schreiber, Fabian; Krott, Nicole; Gries, Thomas; Liehn, Elisa; Blindt, Rüdiger; Marx, Nikolaus; Vogt, Felix

    2012-11-01

    Current stent system efficacy for the treatment of coronary artery disease is hampered by in-stent restenosis (ISR) rates of up to 20% in certain high-risk settings and by the risk of stent thrombosis, which is characterized by a high mortality rate. In theory, biodegradable vascular devices exhibit crucial advantages. Most absorbable implant materials are based on poly-L-lactic acid (PLLA) owing to its mechanical properties; however, PLLA might induce an inflammatory reaction in the vessel wall. Evaluation of biodegradable implant efficacy includes a long-term examination of tissue response; therefore, a simple in vivo tool for thorough biocompatibility and biodegradation evaluation would facilitate future stent system development. Rats have been used for the study of in vivo degradation processes, and stent implantation into the abdominal aorta of rats is a proven model for stent evaluation. Here, we report the transformation of the porcine double-stent animal model into the high-throughput rat abdominal aorta model. As genetic manipulation of rats was introduced recently, this novel method presents a powerful tool for future in vivo biodegradable candidate stent biocompatibility and biodegradation characterization in a reliable simple model of coronary ISR. Copyright © 2012 Wiley Periodicals, Inc.

  3. Initial experience with a new biodegradable airway stent in children: Is this the stent we were waiting for?

    Science.gov (United States)

    Antón-Pacheco, Juan L; Luna, Carmen; García, Enrique; López, María; Morante, Rocío; Tordable, Cristina; Palacios, Alba; de Miguel, Mónica; Benavent, Isabel; Gómez, Andrés

    2016-06-01

    To report our experience with a new type of biodegradable airway stent in the setting of severe tracheobronchial obstruction in children. We conducted a retrospective and prospective (since June 2014) study of pediatric patients with severe airway obstruction treated with biodegradable stents in our institution between 2012 and 2015. The following data were collected: demographics, indication for stenting, bronchoscopic findings, insertion technique complications, clinical outcome, stent related complications, re-stenting, and time of follow-up. Thirteen custom-made polydioxanone stents were placed in four infants (mean age, 4 months) with severe tracheobronchial obstruction: tracheomalacia (two patients), bronchomalacia (1), and diffuse tracheal stenosis (1). All the stents were bronchoscopically inserted uneventfully. Immediate and maintained clinical improvement was observed in every case. No major stent related complications have occurred and only mild or moderate granulation tissue was observed during surveillance bronchoscopy. Two patients required repeated stenting as expected. All the patients are alive and in a good respiratory condition with a follow-up ranging from 5 to 40 months. Biodegradable airway stents seem to be safe, effective, and cause fewer complications than other types of stents. They can be an alternative to the classic metallic or plastic stents for severe tracheal stenosis or malacia in small children. More experience is needed in order to establish the definite clinical criteria for their use in pediatric patients. Pediatr Pulmonol. 2016;51:607-612. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.

  4. Stent Fracture and Reocclusion After Placement of a Single Self-Expanding Stent in the Common Iliac Artery and Endovascular Treatment

    International Nuclear Information System (INIS)

    Higashiura, Wataru; Sakaguchi, Shoji; Morimoto, Kengo; Kichikawa, Kimihiko

    2008-01-01

    We present a case of fracture of a single self-expanding stent placed in the common iliac artery (CIA). An 80-year-old woman underwent placement of a self-expanding stent for CIA occlusion. Stent fracture and reocclusion were detected after 18 months. Successful revascularization was achieved using a stent-in-stent maneuver. The possibility of stent fracture with reocclusion should be considered following treatment with a single self-expanding stent for CIA occlusion.

  5. Intraluminal Radioactive Stent Compared with Covered Stent Alone for the Treatment of Malignant Esophageal Stricture

    International Nuclear Information System (INIS)

    Wang Zhongmin; Huang Xunbo; Cao Jun; Huang Gang; Chen Kemin; LIu Yu; Liu Fenju

    2012-01-01

    Objective: This study was designed to compare the clinical effectiveness of intraluminal radioactive stent loaded with iodine-125 seeds implantation versus covered stent alone insertion in patients with malignant esophageal stricture. Methods: We studied two groups of patients with malignant esophageal stricture. Group A comprised 28 patients (19 men and 9 women) who underwent intraluminal radioactive stent loaded with iodine-125 seeds implantation and were followed prospectively. Group B comprised 30 patients (18 men and 12 women) who had previously received covered stent alone insertion; these patients were evaluated retrospectively. There was no crossover between the two groups during follow-up. Informed consent was obtained from each patient, and our institutional review board approved the study. The dysphagia score, overall survival rates, complication rates, and reintervention rates were compared in the two groups. Results: There were no significant differences between the two groups in terms of baseline characteristics. Stent placement was technically successful and well tolerated in all patients. The dysphagia score was improved in both groups after stent placement. The median survival was significantly longer in group A than in group B: 11 versus 4.9 months, respectively (P < 0.001). The complications of chest pain, esophageal reflux, and stent migration was more frequent in group B, but this difference did not reach statistical significance. There was no statistical difference in reintervention between two groups. Conclusions: Intraluminal radioactive stent loaded with iodine-125 seeds implantation was a feasible and practical management in treating malignant esophageal stricture and was superior to covered stent alone insertion, as measured by survival.

  6. The Incidence and Risk Factors of In-Stent Restenosis for Vertebrobasilar Artery Stenting.

    Science.gov (United States)

    Zheng, Dai; Mingyue, Zhu; Wei, Shi; Min, Li; Wanhong, Chen; Qiliang, Dai; Yongjun, Jiang; Xinfeng, Liu

    2018-02-01

    In-stent restenosis (ISR) remains a challenge for vertebrobasilar artery stenting (VBAS). We aimed to investigate the incidence and risk factors of ISR. This was a retrospective study. From July 28, 2005, to July 30, 2015, patients who received VBAS with an angiographic follow-up time of 6 to 12 months after surgery were enrolled. The clinical and angiographic issues were recorded and analyzed. In total, 283 patients with 335 stents were incorporated into the study. Vertebral ostial lesions accounted for 73.4% (246/335) of the lesions. During the follow-up period, 58 patients with 60 stents experienced ISR (>50%). Stepwise logistic regression analysis showed that the degree of residual stenosis, stent diameter, and alcohol consumption were independent predictors of ISR. Our study demonstrated the incidence and risk factors of ISR after VBAS. This retrospective study with the largest cohort to date provided insight into the occurrence of ISR after VBAS. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Magnetizable stent-grafts enable endothelial cell capture

    Energy Technology Data Exchange (ETDEWEB)

    Tefft, Brandon J. [Department of Cardiovascular Diseases, Mayo Clinic, Rochester, MN (United States); Uthamaraj, Susheil [Division of Engineering, Mayo Clinic, Rochester, MN (United States); Harburn, J. Jonathan [School of Medicine, Pharmacy and Health, Durham University, Stockton-on-Tees (United Kingdom); Hlinomaz, Ota [Department of Cardioangiology, St. Anne' s University Hospital, Brno (Czech Republic); Lerman, Amir [Department of Cardiovascular Diseases, Mayo Clinic, Rochester, MN (United States); Dragomir-Daescu, Dan [Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN (United States); Sandhu, Gurpreet S., E-mail: sandhu.gurpreet@mayo.edu [Department of Cardiovascular Diseases, Mayo Clinic, Rochester, MN (United States)

    2017-04-01

    Emerging nanotechnologies have enabled the use of magnetic forces to guide the movement of magnetically-labeled cells, drugs, and other therapeutic agents. Endothelial cells labeled with superparamagnetic iron oxide nanoparticles (SPION) have previously been captured on the surface of magnetizable 2205 duplex stainless steel stents in a porcine coronary implantation model. Recently, we have coated these stents with electrospun polyurethane nanofibers to fabricate prototype stent-grafts. Facilitated endothelialization may help improve the healing of arteries treated with stent-grafts, reduce the risk of thrombosis and restenosis, and enable small-caliber applications. When placed in a SPION-labeled endothelial cell suspension in the presence of an external magnetic field, magnetized stent-grafts successfully captured cells to the surface regions adjacent to the stent struts. Implantation within the coronary circulation of pigs (n=13) followed immediately by SPION-labeled autologous endothelial cell delivery resulted in widely patent devices with a thin, uniform neointima and no signs of thrombosis or inflammation at 7 days. Furthermore, the magnetized stent-grafts successfully captured and retained SPION-labeled endothelial cells to select regions adjacent to stent struts and between stent struts, whereas the non-magnetized control stent-grafts did not. Early results with these prototype devices are encouraging and further refinements will be necessary in order to achieve more uniform cell capture and complete endothelialization. Once optimized, this approach may lead to more rapid and complete healing of vascular stent-grafts with a concomitant improvement in long-term device performance. - Highlights: • Magnetic stent-grafts were made from 2205 steel stents and polyurethane nanofibers. • Stent-grafts remained patent and formed a thin and uniform neointima when implanted. • Stent-grafts captured endothelial cells labeled with magnetic nanoparticles.

  8. Covered stent placement for the treatment of malignant superior vena cava syndrome: Is unilateral covered stenting and effective?

    International Nuclear Information System (INIS)

    Cho, Young Hoon; Gwon, Dong Il; Ko, Gi Young; Ko, Heung Kyu; Kim, Jin Hyoung; Shin, Ji Hoon; Yoon, Hyun Ki; Sung, Kyu Bo

    2014-01-01

    To evaluate the safety and efficacy of unilateral covered stent placement in patients with malignant superior vena cava (SVC) syndrome. Between October 2008 and November 2012, expanded polytetrafluoroethylene-covered stent placement for malignant SVC syndrome was performed in 40 consecutive patients (35 men and five women; mean age, 61.4 years; range, 35-81 years). All covered stents were unilaterally placed within the SVC or across the venous confluence when needed to relieve venous obstruction and prevent tumor overgrowth, regardless of patency of contralateral brachiocephalic veins. Stent placement was technically successful in all patients. There were no major complications. Of the 37 patients symptomatic prior to stent placement, 34 (92%) experienced complete symptomatic relief 1-8 days after stent placement. Of the 29 patients who underwent covered stent placement across the venous confluence, nine patients had patent contralateral brachiocephalic veins prior to stent placement. However, no sign of SVC obstruction or contralateral upper extremity venous thrombosis was observed during the follow-up period. Kaplan-Meier analysis revealed median patient survival of 163 days. Stent occlusion occurred in four (10%) of 40 patents. Cumulative stent patency rates at 1, 3, 6, and 12 months were 95%, 92%, 86%, and 86%, respectively. Unilateral covered stent placement appears to be a safe and effective method for treating malignant SVC syndrome, despite the location of SVC occlusion.

  9. Covered stent placement for the treatment of malignant superior vena cava syndrome: Is unilateral covered stenting and effective?

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Young Hoon; Gwon, Dong Il; Ko, Gi Young; Ko, Heung Kyu; Kim, Jin Hyoung; Shin, Ji Hoon; Yoon, Hyun Ki; Sung, Kyu Bo [Dept. of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul (Korea, Republic of)

    2014-02-15

    To evaluate the safety and efficacy of unilateral covered stent placement in patients with malignant superior vena cava (SVC) syndrome. Between October 2008 and November 2012, expanded polytetrafluoroethylene-covered stent placement for malignant SVC syndrome was performed in 40 consecutive patients (35 men and five women; mean age, 61.4 years; range, 35-81 years). All covered stents were unilaterally placed within the SVC or across the venous confluence when needed to relieve venous obstruction and prevent tumor overgrowth, regardless of patency of contralateral brachiocephalic veins. Stent placement was technically successful in all patients. There were no major complications. Of the 37 patients symptomatic prior to stent placement, 34 (92%) experienced complete symptomatic relief 1-8 days after stent placement. Of the 29 patients who underwent covered stent placement across the venous confluence, nine patients had patent contralateral brachiocephalic veins prior to stent placement. However, no sign of SVC obstruction or contralateral upper extremity venous thrombosis was observed during the follow-up period. Kaplan-Meier analysis revealed median patient survival of 163 days. Stent occlusion occurred in four (10%) of 40 patents. Cumulative stent patency rates at 1, 3, 6, and 12 months were 95%, 92%, 86%, and 86%, respectively. Unilateral covered stent placement appears to be a safe and effective method for treating malignant SVC syndrome, despite the location of SVC occlusion.

  10. Renal PTA stenting

    International Nuclear Information System (INIS)

    Tsetis, D.

    2012-01-01

    Full text: Renal artery stenosis (RAS) is a common condition that may lead to hypertension, progressive renal dysfunction and cardiovascular morbidity. Catheter-based therapy for symptomatic, haemodynamically significant, RAS has become the preferred method of revascularization. Balloon angioplasty has been the traditional treatment of choice for fibromuscular dysplasia, however stents are increasingly used for the treatment of atheromatous lesions; in many cases-such as in ostial lesions-, direct stenting is strongly indicated. Despite the increased use of endovascular therapy for renal artery stenosis, there is still controversy regarding the optimal management and the net benefit of this treatment. Several randomized trials of balloon angioplasty or stenting for renal artery stenosis compared with medical therapy alone have been conducted, however these could not show definite advantage of endovascular therapy. Problems encountered with those trials include enrollment of small number of patients, frequent crossover from medical to interventional therapy compromising the intention-to-treat results, or selection of patients that are not expected to show clear benefit. The Angioplasty and Stenting for Renal Artery Lesions (ASTRAL) is the most important of these trials; however, it,s study design was faulty and therefore did not provide conclusive evidence to answer the question of whether angioplasty and stenting or medical therapy is the best treatment for haemodynamically significant RAS. All expectations are now focused on the Cardiovascular Outcomes in Renal Atherosclerotic Lesions (CORAL) trial which was designed to answer the same question, and its methodologies took into consideration the weaknesses of the ASTRAL trial. Regarding stent device itself, it seems that the optimal design is probably a stainless steel, laser cut, open-cells stent mounted on a rapid exchange delivery balloon catheter compatible with 0.014-in and 0.018-in guidewire. As a future

  11. Influence of covered stent versus bare stent on long-term efficacy of transjugular intrahepatic portosystemic shunt: a meta-analysis

    Directory of Open Access Journals (Sweden)

    XU Lu

    2016-10-01

    Full Text Available Objective To investigate the long-term postoperative efficacy of transjugular intrahepatic portosystemic shunt (TIPS using polytetrafluoroethylene (PTFE-covered stent or bare stent, and to provide a basis of evidence-based medicine for the selection of stent in TIPS. Methods CBM, Wanfang Data, CNKI, VIP, MEDLINE, and PubMed were searched for controlled trials on TIPS in the treatment of cirrhotic portal hypertension published form 1989 to 2015; the studies which met the inclusion criteria were selected, and quality assessment was performed for these articles. RevMan 5.3 software was used to analyze the incidence rates of stent dysfunction and hepatic encephalopathy and 1-year survival rate after TIPS, and funnel plots were used to analyze publication bias. Results A total of 11 studies were included, consisting of 698 patients in PTFE-covered stent group and 1283 patients in bare stent group. The results of the meta-analysis showed that the PTFE-covered stent group showed a significantly lower incidence rate of stent dysfunction than the bare stent group (14.8% vs 47.0%, OR=0.18, 95% CI: 0.13-0.24, P<0.001. There was no significant difference in the incidence rate of hepatic encephalopathy between the two groups (23.5% vs 25.7%, OR=0.88, 95% CI: 0.66-1.17, P=0.37. The PTFE-covered stent group had a significantly higher 1-year survival rate than the bare stent group (76.9% vs 62.7%, OR=2.10, 95% CI: 1.54-2.85, P<0.001. The funnel plots which were plotted based on the incidence rates of stent dysfunction and hepatic encephalopathy and 1-year survival rate lacked symmetry, which suggested that a certain degree of publication bias might exist. Conclusion Compared with the bare stent, the PTFE-covered stent can improve stent dysfunction and 1-year survival rate after TIPS, while there is no significant change in the incidence rate of hepatic encephalopathy. Therefore, the PTFE-covered stent has certain advantages over the bare stent in TIPS. In

  12. Long-Term Type 1 Diabetes Enhances In-Stent Restenosis after Aortic Stenting in Diabetes-Prone BB Rats

    Directory of Open Access Journals (Sweden)

    Geanina Onuta

    2011-01-01

    Full Text Available Type 1 diabetic patients have increased risk of developing in-stent restenosis following endovascular stenting. Underlying pathogenetic mechanisms are not fully understood partly due to the lack of a relevant animal model to study the effect(s of long-term autoimmune diabetes on development of in-stent restenosis. We here describe the development of in-stent restenosis in long-term (~7 months spontaneously diabetic and age-matched, thymectomized, nondiabetic Diabetes Prone BioBreeding (BBDP rats (n=6-7 in each group. Diabetes was suboptimally treated with insulin and was characterized by significant hyperglycaemia, polyuria, proteinuria, and increased HbA1c levels. Stented abdominal aortas were harvested 28 days after stenting. Computerized morphometric analysis revealed significantly increased neointima formation in long-term diabetic rats compared with nondiabetic controls. In conclusion, long-term autoimmune diabetes in BBDP rats enhances in-stent restenosis. This model can be used to study the underlying pathogenetic mechanisms of diabetes-enhanced in-stent restenosis as well as to test new therapeutic modalities.

  13. Endotracheal expandable metallic stent placement in dogs

    Energy Technology Data Exchange (ETDEWEB)

    Sawada, S; Tanabe, Y; Fujiwara, Y; Koyama, T; Tanigawa, N; Kobayashi, M; Katsube, Y; Nakamura, H [Tottori Univ. School of Medicine, Yonago (Japan). Dept. of Radiology Research Inst. for Microbial Diseases, Osaka (Japan). Dept. of Radiology

    1991-01-01

    Various types of Gianturco zig-zag wire stent were implanted into the tracheas of 4 dogs to define the suitable characteristics of the endotracheal wire stent in these animals. These stents were constructed of 0.45, and 0.33 mm stainless steel wire. The diameter of the fully expanded stents was 3 cm and their lengths were 2, 3, and 4 cm. The 2 cm stent constructed of 0.33 mm wire showed minimum pathologic changes of the trachea of the dog compared to the other stents, and at the same time had a complete covering of ciliated columnar epithelium over the stent surface. (orig.).

  14. Covered metal stent or multiple plastic stents for refractory pancreatic ductal strictures in chronic pancreatitis: a systematic review.

    Science.gov (United States)

    Shen, Yonghua; Liu, Mingdong; Chen, Min; Li, Yunhong; Lu, Ying; Zou, Xiaoping

    2014-01-01

    Refractory chronic pancreatitis has been proposed as a challenge for endoscopists following routine single plastic stenting. However, data on the efficacy and safety of further endoscopic stenting are still controversial. The current systematic review aimed to assess the efficacy and safety of placement of fully covered self-expandable metal stent (FCSEMS) and multiple plastic stents. Databases including MEDLINE, EMBASE, the Cochrane Library, CBM, CNKI, VIP, and WANFANG Database were used to search relevant trials. Published studies were assessed by using well-defined inclusion and exclusion criteria. The process was independently performed by two investigators. A total of 5 studies provided data of 80 patients. Forest plots and publication bias were not carried out because few studies were relevant and screened studies were all case series. The technical success rate was 100% both in placement of FCSEMS and multiple plastic stents. The functional success rate after placement of FCSEMS was 100%, followed by multiple plastic stents (94.7%). Complications occurred 26.2% after FCSEMS placement, which was not described in detail in multiple plastic stents. The stent migration rate was 8.2% for FCSEMS and 10.5% for multiple plastic stents. Reintervention rate was 9.8% for FCSEMS and 15.8% for multiple plastic stents. Pain improvement rate was 85.2% for FCSEMS and 84.2% for multiple plastic stents. FCSEMS appeared to be no significant difference with multiple plastic stents in treatment of refractory chronic pancreatitis. We need to develop more investigations. Copyright © 2014 IAP and EPC. Published by Elsevier B.V. All rights reserved.

  15. Particle imaging velocimetry evaluation of intracranial stents in sidewall aneurysm: hemodynamic transition related to the stent design.

    Science.gov (United States)

    Bouillot, Pierre; Brina, Olivier; Ouared, Rafik; Lovblad, Karl-Olof; Farhat, Mohamed; Pereira, Vitor Mendes

    2014-01-01

    We investigated the flow modifications induced by a large panel of commercial-off-the-shelf (COTS) intracranial stents in an idealized sidewall intracranial aneurysm (IA). Flow velocities in IA silicone model were assessed with and without stent implantation using particle imaging velocimetry (PIV). The use of the recently developed multi-time-lag method has allowed for uniform and precise measurements of both high and low velocities at IA neck and dome, respectively. Flow modification analysis of both regular (RSs) and flow diverter stents (FDSs) was subsequently correlated with relevant geometrical stent parameters. Flow reduction was found to be highly sensitive to stent porosity variations for regular stents RSs and moderately sensitive for FDSs. Consequently, two distinct IA flow change trends, with velocity reductions up to 50% and 90%, were identified for high-porosity RS and low-porosity FDS, respectively. The intermediate porosity (88%) regular braided stent provided the limit at which the transition in flow change trend occurred with a flow reduction of 84%. This transition occurred with decreasing stent porosity, as the driving force in IA neck changed from shear stress to differential pressure. Therefore, these results suggest that stents with intermediate porosities could possibly provide similar flow change patterns to FDS, favourable to curative thrombogenesis in IAs.

  16. Covered Balloon-Expanding Stents in Airway Stenosis.

    Science.gov (United States)

    Majid, Adnan; Kheir, Fayez; Chung, Jey; Alape, Daniel; Husta, Bryan; Oh, Scott; Folch, Erik

    2017-04-01

    The balloon-expanding stents are widely available but rarely described for use within the tracheobronchial tree. This report describes our experience with these stents in airway stenosis particularly as a lobar salvage therapy. This was a retrospective review of all records in which the balloon-expanding stents were used at a tertiary medical center. Ages, sex, location of stenosis, etiology of stenosis, stent size, duration of stent placement and associated interventions for airway stenosis were recorded. Patient's self-reported respiratory symptoms, dyspnea scale, and radiographic imaging at baseline and after stent placement were also reported. Twenty-one Atrium iCAST stents were inserted in 18 patients with malignant and benign airway disease. The median age was 69.5 years (interquartile range, 53.5 to 74). Most stents (n=20, 95%) were deployed in the lobar airways. There was a significant improvement in the modified Medical Research Council dyspnea scale from median of 3 to 2 (Pstent placement was achieved in 15 patients (83%). No deaths were related to airway stenting complications. Adverse events related to stents included migration (n=2, 9.5%), granulation tissue formation (n=2, 9.5%) and mucus plugging (n=1, 4.8%). Lobar stenting with balloon-expanding metallic stents appears feasible, safe and improves symptoms as well as radiographic atelectasis in patients with lobar airway stenosis in this small case series. Larger studies are needed to confirm this observation and to address long-term safety.

  17. In vitro stent lumen visualisation of various common and newly developed femoral artery stents using MR angiography at 1.5 and 3 tesla.

    Science.gov (United States)

    Syha, R; Ketelsen, D; Kaempf, M; Mangold, S; Sixt, S; Zeller, T; Springer, F; Schick, F; Claussen, C D; Brechtel, K

    2013-02-01

    To evaluate stent lumen assessment of various commonly used and newly developed stents for the superficial femoral artery (SFA) using MR angiography (MRA) at 1.5 and 3 T. Eleven nitinol stents and one cobalt-chromium stent were compared regarding stent lumen visualisation using a common three-dimensional MRA sequence. Maximum visible stent lumen width and contrast ratio were analysed in three representative slices for each stent type. A scoring system for lumen visualisation was applied. Nitinol stents showed significantly better performance than the cobalt chromium stent (P stent lumen ranged between 43.4 and 95.5 %, contrast ratio between 7.2 and 110.6 %. Regarding both field strengths, seven of the nitinol stents were classified as "suitable". Three nitinol stents were "limited", and one nitinol stent and the cobalt chromium stent were "not suitable". Intraluminal loss of signal and artefacts of most of the SFA stents do not markedly limit assessment of stent lumen by MRA at 1.5 and 3 T. MRA can thus be considered a valid technique for detection of relevant in-stent restenosis. Applied field strength does not strongly influence stent lumen assessment in general, but proper choice of field strength might be helpful.

  18. Novel 3D-CT evaluation of carotid stent volume: greater chronological expansion of stents in patients with vulnerable plaques.

    Science.gov (United States)

    Itami, Hisakazu; Tokunaga, Koji; Okuma, Yu; Hishikawa, Tomohito; Sugiu, Kenji; Ida, Kentaro; Date, Isao

    2013-09-01

    Although self-expanding carotid stents may dilate gradually, the degrees of residual stenosis have been quantified by the NASCET criteria, which is too simple to reflect the configuration of the stented artery. We measured the volumes of the stent lumens chronologically by 3D-CT in patients after carotid artery stenting (CAS), and analyzed the correlations between the volume change and medical factors. Fourteen patients with carotid artery stenosis were treated using self-expanding, open-cell stents. All patients underwent preoperative plaque MRI (magnetization-prepared rapid acquisition gradient-echo, MPRAGE) and chronological 3D-CT examinations of their stents immediately after their placement and 1 day, 1 week, and 1 month after the procedure. The volume of the stent lumen was measured using a 3D workstation. The correlations between stent volume and various factors including the presence of underlying diseases, plaque characteristics, and the results of the CAS procedure were analyzed. Stent volume gradually increased in each case and had increased by 1.04-1.55 (mean, 1.25)-fold at 1 postoperative month. The presence of underlying medical diseases, plaque length, the degree of residual stenosis immediately after CAS, and plaque calcification did not have an impact on the change in stent volume. On the other hand, the stent volume increase was significantly larger in the patients with vulnerable plaques that demonstrated high MPRAGE signal intensity (P stent volume. Self-expanding stents in carotid arteries containing vulnerable plaques expand significantly more than those without such plaques in a follow-up period.

  19. Fluoroscopically guided placement of self-expandable metallic stents and stent-grafts in the treatment of acute malignant colorectal obstruction.

    Science.gov (United States)

    Kim, Honsoul; Kim, Seung Hyoung; Choi, Sun Young; Lee, Kwang-Hun; Won, Jong Yoon; Lee, Do Yun; Lee, Jong Tae

    2008-12-01

    To evaluate the technical feasibility and clinical effectiveness of fluoroscopically guided placement of self-expandable metallic stents and stent-grafts for acute malignant colorectal obstruction. Radiologic images and clinical reports of 42 patients (22 men, 20 women; age range, 28-93 years; median age, 65.5 years) who underwent fluoroscopically guided colorectal stent insertion without endoscopic assistance for acute malignant obstruction were reviewed retrospectively. Eighteen patients received bare stents as a bridge to surgery. Twenty-four patients received 27 insertions of either a bare stent (n = 15) or a stent-graft (n = 12) for palliation. The obstruction was located in the rectum (n = 8), sigmoid (n = 17), descending colon (n = 8), splenic flexure (n = 3), and transverse colon (n = 6). Clinical success, defined as more than 50% dilatation of the stent with subsequent symptomatic improvement, was achieved in 41 of the 42 patients (98%). No major procedure-related complications occurred. Minor complications occurred in eight of the 45 procedures (18%). No perioperative mortalities occurred within 1 month after surgery. In the palliative group, the median stent patency was 62 days (range, 0-1,014 days). There was no statistically significant difference in stent patency between the bare stents (range, 0-855 days; median, 68 days) and stent-grafts (range, 1-1,014 days; median, 81 days). Fluoroscopically guided placement of self-expandable metallic stents and stent-grafts for the relief of acute malignant colorectal obstruction was technically feasible without endoscopic assistance-even in lesions proximal to the splenic flexure and transverse colon-and clinically effective in both bridge to surgery and palliative management.

  20. Changes in the mechanical environment of stenotic arteries during interaction with stents: computational assessment of parametric stent designs.

    Science.gov (United States)

    Holzapfel, Gerhard A; Stadler, Michael; Gasser, Thomas C

    2005-02-01

    Clinical studies have identified factors such as the stent design and the deployment technique that are one cause for the success or failure of angioplasty treatments. In addition, the success rate may also depend on the stenosis type. Hence, for a particular stenotic artery, the optimal intervention can only be identified by studying the influence of factors such as stent type, strut thickness, geometry of the stent cell, and stent-artery radial mismatch with the wall. We propose a methodology that allows a set of stent parameters to be varied, with the aim of evaluating the difference in the mechanical environment within the wall before and after angioplasty with stenting. Novel scalar quantities attempt to characterize the wall changes inform of the contact pressure caused by the stent struts, and the stresses within the individual components of the wall caused by the stent. These quantities are derived numerically and serve as indicators, which allow the determination of the correct size and type of the stent for each individual stenosis. In addition, the luminal change due to angioplasty may be computed as well. The methodology is demonstrated by using a full three-dimensional geometrical model of a postmortem specimen of a human iliac artery with a stenosis using imaging data. To describe the material behavior of the artery, we considered mechanical data of eight different vascular tissues, which formed the stenosis. The constitutive models for the tissue components capture the typical anisotropic, nonlinear and dissipative characteristics under supra-physiological loading conditions. Three-dimensional stent models were parametrized in such a way as to enable new designs to be generated simply with regard to variations in their geometric structure. For the three-dimensional stent-artery interaction we use a contact algorithm based on smooth contact surfaces of at least C-continuity, which prevents numerical problems known from standard facet-based contact

  1. Retreatment of recanalized aneurysms after Y-stent-assisted coil embolization with double enterprise stents: case report and systematic review of the literature.

    Science.gov (United States)

    Kono, Kenichi; Shintani, Aki; Terada, Tomoaki

    2014-01-01

    It is necessary to consider possibility of recanalization and retreatment after coil embolization for cerebral aneurysms. There is concern that retreatment for recanalized aneurysms after Y-stent-assisted coil embolization may be difficult because of double stents, especially in Y-stents with double closed-cell stents owing to narrowed structures. However, no detailed reports of retreatment after Y-stent have been reported. Between July 2010 and June 2013, we treated four aneurysms with Y-stent-assisted coil embolization using Enterprise closed-cell stents. Recanalization occurred in one case (25%), and retreatment was performed. We easily navigated a microcatheter into the target portions of the aneurysm through the Y-stent and occluded the aneurysm with coils. Additionally, by systematically searching in PubMed, we found 105 cases of Y-stent-assisted coil embolization using Enterprise stents or Neuroform stents with more than 6 months of follow-up. Among them, retreatment was performed in 10 cases (9.5%). There were no significant differences in retreatment rates among different stent combinations (P=0.91; Fisher's exact test). In conclusion, navigation of a microcatheter into the aneurysm through the Y-stent with double Enterprise stents was feasible, and retreatment rates after Y-stent-assisted coiling may not depend on stent combinations.

  2. Angioplasty and stent placement - carotid artery

    Science.gov (United States)

    ... medlineplus.gov/ency/article/002953.htm Angioplasty and stent placement - carotid artery To use the sharing features ... to remove plaque buildup ( endarterectomy ) Carotid angioplasty with stent placement Description Carotid angioplasty and stenting (CAS) is ...

  3. Comparison of in vivo acute stent recoil between the bioabsorbable everolimus-eluting coronary stent and the everolimus-eluting cobalt chromium coronary stent: insights from the ABSORB and SPIRIT trials

    DEFF Research Database (Denmark)

    Tanimoto, Shuzou; Serruys, Patrick W; Thuesen, Leif

    2007-01-01

    OBJECTIVES: This study sought to evaluate and compare in vivo acute stent recoil of a novel bioabsorbable stent and a metallic stent. BACKGROUND: The bioabsorbable everolimus-eluting coronary stent (BVS) is composed of a poly-L-lactic acid backbone, coated with a bioabsorbable polymer containing...... the antiproliferative drug, everolimus, and expected to be totally metabolized and absorbed in the human body. Because the BVS is made from polymer, it may have more acute recoil than metallic stents in vivo. METHODS: A total of 54 patients, who underwent elective stent implantation for single de novo native coronary...... artery lesions, were enrolled: 27 patients treated with the BVS and 27 patients treated with the everolimus-eluting cobalt chromium stent (EES). Acute absolute recoil, assessed by quantitative coronary angiography, was defined as the difference between mean diameter of the last inflated balloon...

  4. Coronary artery aneurysm after stent implantation: acute and long-term results after percutaneous treatment with a stent graft.

    Science.gov (United States)

    Rubartelli, Paolo; Terzi, Giacomo; Borgo, Lorenzo; Giachero, Corinna

    2002-03-01

    A patient with unstable angina was treated with elective Palmaz-Schatz stent implantation on a focal stenosis of the left circumflex artery. One year later, a large (13 mm in diameter) coronary artery aneurysm was diagnosed at angiography in the stented site. Intravascular ultrasound examination confirmed the presence of a true aneurysm located at the proximal end of the stent. The aneurysm was successfully treated with a Jostent Graft (Jomed Implantate) consisting of two slotted tube stainless steel stents supporting a polytetrafluoroethylene tube. The stent graft was implanted under intravascular ultrasound guidance. The 18-month angiographic follow-up showed good patency of the stent graft and complete exclusion of the aneurysm.

  5. Endobronchial Occlusion Stent: A Preliminary Experimental Study

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Yo Won; Jeong, Woo Kyoung; Lee, Seoung Hoon; Heo, Jeong Nam; Jeon, Seok Chol [Hanyang University College of Medicine, Seoul (Korea, Republic of); Ko, Gi Young; Song, Ho Young [University of Ulsan College of Medicine, Ulsan (Korea, Republic of)

    2010-04-15

    To evaluate the safety and the technical feasibility of the use of an endobronchial occlusion stent and to get preliminary data for the development of the optimal material required for endobronchial occlusions. A commercialized, self-expandable tracheobronchial stent was modified; one half had a polyurethane cover with an occluded end and the other half was uncovered with a flaring configuration. The occluded end was placed such that it would face the distal lung. Under fluoroscopic guidance, seven stents were placed at the lower lobar bronchus in 6 mini-pigs. The bronchial obstruction was examined immediately after stent placement. Chest radiographs were taken at days 1, 7, 14, and 28 after stent placement and the removed airways from two, two, one, and one mini-pigs sacrificed on corresponding days were examined for the maintenance of bronchial obstruction. Stents were successfully placed and induced the immediate bronchial obstruction in all mini-pigs. Five of seven airways with occlusion stents maintained an obstruction until the mini-pigs were sacrificed. Proximal stent migration occurred in two mini-pigs (29%), and pulmonary consolidations were observed distal to four of the stents (57%). The placement of an endobronchial occlusion stent and the obstruction of targeted bronchi seem to be feasible, but an add-on check valve should be considered to prevent stent migration and obstructive pneumonia

  6. Carotid Angioplasty and Stenting

    Science.gov (United States)

    Carotid angioplasty and stenting Overview Carotid angioplasty (kuh-ROT-id AN-jee-o-plas-tee) and stenting ... to better see and examine the blood vessels. Food and medications You'll receive instructions on what ...

  7. Self-Expandable Metallic Stent Placement in Malignant Gastric Outlet Obstruction: A Comparison Between 2 Brands of Stents.

    Science.gov (United States)

    Ye, Bing-Wei; Lee, Kuei-Chuan; Hsieh, Yun-Cheng; Li, Chung-Pin; Chao, Yee; Hou, Ming-Chih; Lin, Han-Chieh

    2015-07-01

    Malignant gastric outlet obstruction is a late complication of intraabdominal malignancy. Self-expandable metallic stent placement has been a safe palliative treatment to relieve obstructive symptoms. We aimed to assess the efficacy and safety of metallic stents in our patients and analyzed the clinical outcome of different brands. Seventy-one patients with inoperable gastric outlet obstruction receiving WallFlex enteral stents (WallFlex group) or Bonastents (Bonastent group) since April 2010 were analyzed retrospectively. The overall technical and clinical success rates of stent placement were 100% and 93%, respectively. The baseline characteristics and clinical outcomes including procedure-related complications, restenosis, and reintervention rates were comparable between the 2 groups. However, the Bonastent group had a higher rate of stent fracture than the WallFlex group (13.3% vs 0%, P = 0.03). The mean duration of overall stent patency was 132.7 days. The mean duration of survival was 181.9 days. Resumption of regular diet or low residual diet at day 7 after stent insertion predicted stent patency (hazard ratio [HR]: 0.28, P = 0.01). Cancer with gastric origin (HR: 0.25, P = 0.045) and poststent chemotherapy (HR: 0.38, P = 0.006) predicted lower mortality; however, peritoneal carcinomatosis (HR: 3.09, P = 0.04) correlated with higher mortality. Metallic stent placement is a safe and effective method for relieving gastric outlet obstruction. Except higher rate of stent fracture in the Bonastent group, there is no significant difference in clinical outcomes between the Bonastent group and the WallFlex group.

  8. Comparison of retrievable stents and permanent stents for Budd-Chiari syndrome due to obstructive inferior vena cava.

    Science.gov (United States)

    Bi, Yonghua; Chen, Hongmei; Ding, Penxu; Ren, Jianzhuang; Han, Xinwei

    2018-05-30

    To compare long-term outcomes of retrievable stents and permanent stents for BCS due to long-segment obstructive IVC. Between July 2000 and August 2016, 42 patients with BCS due to long-segment obstructive IVC were treated with retrievable stents (RS) and 41 patients were treated with permanent stents (PS). The retrievable stents was removed eventually after thrombus disappeared. Patients were subsequently followed-up by color Doppler sonography or CT scanning. All retrievable stent placements were successfully, and 37 retrievable stents were retrieved 8 to 29 days later. Forty-two stents were implanted in PS Group. One failure retrieval of retrievable stents occurred, and two failures of cannulations were found in PS Group. Two deaths may procedure-related and died from acute pulmonary thromboembolism perioperatively. One patient developed acute cerebral infarction and recovered after treatment. In PS Group, minor complications were found in 3 patients. The length of IVC lesion segment, length and thickness of IVC thrombus decreased significantly, and diameter of retrocaval IVC and diaphragm IVC increased significantly in both groups. During follow up, 3 patients died from liver failure in RS Group and 2 patients died in PS Group. RS Group showed a significantly higher primary patency rate than PS Group. Cumulative 1-, 3-, and 5-year secondary patency rates were 95.2%, 89.6%, 89.6% in RS Group, and 100%, 96.6%, 96.6% in PS Group (p= 0.7109). Retrievable stents is effective for BCS due to long-segment obstructive IVC, with a higher primary patency rate. This article is protected by copyright. All rights reserved.

  9. Dual-Source CT Angiography of Peripheral Arterial Stents: In Vitro Evaluation of 22 Different Stent Types

    Directory of Open Access Journals (Sweden)

    Michael Köhler

    2011-01-01

    Full Text Available Purpose. To test different peripheral arterial stents using four image reconstruction approaches with respect to lumen visualization, lumen attenuation and image noise in dual-source multidetector row CT (DSCT in vitro. Methods and Materials. 22 stents (nitinol, steel, cobalt-alloy, tantalum, platinum alloy were examined in a vessel phantom. All stents were imaged in axial orientation with standard parameters. Image reconstructions were obtained with four different convolution kernels. To evaluate visualization characteristics of the stent, the lumen diameter, intraluminal density and noise were measured. Results. The mean percentage of the visible stent lumen diameter from the nominal stent diameter was 74.5% ± 5.7 for the medium-sharp kernel, 72.8% ± 6.4 for the medium, 70.8% ± 6.4 for the medium-smooth and 67.6% ± 6.6 for the smooth kernel. Mean values of lumen attenuation were 299.7HU ± 127 (medium-sharp, 273.9HU ± 68 (medium, 270.7HU ± 53 (medium-smooth and 265.8HU ± 43. Mean image noise was: 54.6 ± 6.3, 20.5 ± 1.7, 16.3 ± 1.7, 14.0 ± 2 respectively. Conclusion. Visible stent lumen diameter varies depending on stent type and scan parameters. Lumen diameter visibility increases with the sharpness of the reconstruction kernel. Smoother kernels provide more realistic density measurements inside the stent lumen and less image noise.

  10. Direct stent puncture technique for intraluminal stent recanalization in the superficial femoral and popliteal arteries in-stent occlusion: Outcomes from a prospective clinical analysis of diabetics with critical limb ischemia

    Energy Technology Data Exchange (ETDEWEB)

    Palena, Luis Mariano, E-mail: marianopalena@hotmail.com; Manzi, Marco

    2013-07-15

    Purpose: To evaluate the efficacy and safety of “Direct Stent Puncture” technique for intraluminal stent recanalization in the femoro-popliteal segments. Methods and Materials: A cohort of diabetics who had symptomatic in-stent occlusion of the superficial femoral or popliteal arteries underwent endovascular recanalization. After antegrade failure, direct stent puncture technique was performed. The primary end-point was to efficacy assessment, intended as technical success and clinical improvement. The secondary end-point was safety assessment, intended as free of complication rate. Results: Fifty-four patients (37 men; 73.6 ± 8.5 years) underwent direct stent puncture technique, after several unsuccessful antegrade attempts to cross the occluded stent. Technical success for intraluminal stent recanalization was achieved in 53/54 (98.2%) of cases and failed in 1/54 (1.8%). Clinical improvement was obtained in 51/54 (94.4%) of cases, with regression of the clinical symptoms and improvement of the TcPO{sub 2}, from 3 ± 18 mmHg to 43 ± 11 mmHg after 15 days (p < 0.001). Free of complications rate was 92.5%. In 2/54 (3.7%) of cases distal embolization occurred, in 1/54 (1.9%) case a sudden vessel thrombosis was diagnosed after 12 hours and in 1/54 (1.9%) case hematoma at the stent puncture site was observed. Conclusions: Direct Stent Puncture technique is an efficacy and safety option for intraluminal stent recanalization in the femoro-popliteal segment in-stent occlusion.

  11. Wing-shaped plastic stents vs. self-expandable metal stents for palliative drainage of malignant distal biliary obstruction: a randomized multicenter study.

    Science.gov (United States)

    Schmidt, Arthur; Riecken, Bettina; Rische, Susanne; Klinger, Christoph; Jakobs, Ralf; Bechtler, Matthias; Kähler, Georg; Dormann, Arno; Caca, Karel

    2015-05-01

    Previous studies have shown superior patency rates for self-expandable metal stents (SEMS) compared with plastic stents in patients with malignant biliary obstruction. The aim of this study was to compare stent patency, patient survival, and complication rates between a newly designed, wing-shaped, plastic stent and SEMSs in patients with unresectable, malignant, distal, biliary obstruction. A randomized, multicenter trial was conducted at four tertiary care centers in Germany. A total of 37 patients underwent randomization between March 2010 and January 2013. Patients underwent endoscopic retrograde cholangiography with insertion of either a wing-shaped, plastic stent without lumen or an SEMS.  Stent failure occurred in 10/16 patients (62.5 %) in the winged-stent group vs. 4/18 patients (22.2 %) in the SEMS group (P = 0.034). The median time to stent failure was 51 days (range 2 - 92 days) for the winged stent and 80 days (range 28 - 266 days) for the SEMS (P = 0.002). Early stent failure (stent failure was significantly higher in the winged-stent group compared with the SEMS group. A high incidence of early stent failure within 8 weeks was observed in the winged-stent group. Thus, the winged, plastic stent without central lumen may not be appropriate for mid or long term drainage of malignant biliary obstruction. Study registration ClinicalTrials.gov (NCT01063634). © Georg Thieme Verlag KG Stuttgart · New York.

  12. Indications for stenting during thrombolysis

    DEFF Research Database (Denmark)

    Bækgaard, N; Broholm, R; Just, Sven Richardt Lundgren

    2013-01-01

    of a stent in this position is the treatment of choice facilitating the venous flow into an unobstructed outflow tract either from the femoral vein or the deep femoral vein or both. The stent, made of stainless steel or nitinol, has to be self-expandable and flexible with radial force to overcome...... the challenges in this low-pressure system. The characteristics of the anatomy with external compression and often a curved vein segment with diameter difference make stent placement necessary. Ballooning alone has no place in this area. The proportion of inserted stents varies in the published materials...

  13. Stent-assisted coiling of intracranial aneurysms using LEO stents: long-term follow-up in 153 patients.

    Science.gov (United States)

    Sedat, Jacques; Chau, Yves; Gaudart, Jean; Sachet, Marina; Beuil, Stephanie; Lonjon, Michel

    2018-02-01

    Coiling associated with placement of a self-expandable intracranial stent has improved the treatment of intracranial wide-necked aneurysms. Little is known, however, about the durability of this treatment. The purpose of this report is to present our experience with the LEO stent and to evaluate the complications, effectiveness, and long-term results of this technique. We analyzed the records of 155 intracranial unruptured aneurysms that were treated by stent-assisted coiling with a LEO stent between 2008 and 2012. Procedural, early post-procedural, and delayed complications were recorded. Clinical and angiographic follow-up of patients was conducted over a period of at least 36 months. No procedural mortality was observed. One-month morbidity was observed in 14 out of 153 patients (9,15%). One hundred thirty-eight patients (with 140 aneurysms) had clinical and angiographic follow-up for more than 36 months. No aneurysm rupture was observed during follow-up. Four patients presented an intra-stent stenosis at 8 months, and 6 patients who had an early recurrence were retreated. Final results showed 85% complete occlusion, 13% neck remnants, and 2% stable incomplete occlusion. Stent-assisted coiling with the LEO stent is a safe and effective treatment for unruptured intracranial aneurysms. The long-term clinical outcomes with the LEO stent are excellent with a high rate of complete occlusion that is stable over time.

  14. Use of flow-diverting stents as salvage treatment following failed stent-assisted embolization of intracranial aneurysms.

    Science.gov (United States)

    Heiferman, Daniel M; Billingsley, Joshua T; Kasliwal, Manish K; Johnson, Andrew K; Keigher, Kiffon M; Frudit, Michel E; Moftakhar, Roham; Lopes, Demetrius K

    2016-07-01

    Flow-diverting stents, including the Pipeline embolization device (PED) and Silk, have been beneficial in the treatment of aneurysms previously unable to be approached via endovascular techniques. Recurrent aneurysms for which stent-assisted embolization has failed are a therapeutic challenge, given the existing intraluminal construct with continued blood flow into the aneurysm. We report our experience using flow-diverting stents in the repair of 25 aneurysms for which stent-assisted embolization had failed. Nineteen (76%) of these aneurysms at the 12-month follow-up showed improved Raymond class occlusion, with 38% being completely occluded, and all aneurysms demonstrated decreased filling. One patient developed a moderate permanent neurologic deficit. Appropriate stent sizing, proximal and distal construct coverage, and preventing flow diverter deployment between the previously deployed stent struts are important considerations to ensure wall apposition and prevention of endoleak. Flow diverters are shown to be a reasonable option for treating previously stented recurrent cerebral aneurysms. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  15. Exclusion of Atherosclerotic Plaque from the Circulation Using Stent-Grafts: Alternative to Carotid Stenting with a Protection Device?

    International Nuclear Information System (INIS)

    Peynircioglu, Bora; Geyik, Serdar; Yavuz, Kivilcim; Cil, Barbaros E.; Saatci, Isil; Cekirge, Saruhan

    2007-01-01

    Purpose. To retrospectively assess the feasibility, safety, and clinical mid-term outcome of patients undergoing carotid artery stenting with stent-grafts. Methods. Over a 4 year period stent-grafts were used in the endovascular treatment of symptomatic internal carotid artery stenosis in 12 patients (2 women, 10 men, aged 47-83 (mean 64) years). Protection devices were not used. Possible microembolic complications were evaluated by magnetic resonance imaging (MRI) examinations of the brain before and the day after the procedure in all patients. Mean follow-up was 22 months (range 1-42 months), by Doppler ultrasonography and conventional angiography as well as clinical examination .Results. The technical success rate was 100%. A total of 13 coronary stent-grafts were used. The mean stenosis rate (in terms of diameter) was 85% and the mean length of stent-grafts used was 20.9 mm. The mean diameter to which the stent-grafts were dilated was 4.66 mm. In-hospital complications occurred in 1 patient who suffered a minor femoral access hematoma that did not require transfusion or surgical decompression. Post-stenting diffusion-weighted MRI revealed several ipsilateral silent microemboli in only 1 case, which was completely asymptomatic. Two patients had a major stroke after 2 years of follow-up. Restenosis was found in 2 patients who underwent successful balloon dilatation followed by placement of a self-expandable bare stent within the stent-grafts. Conclusions. Stent-grafts may prevent microembolic complications during stenting of atherosclerotic carotid lesions in selected cases, offering immediate exclusion of the atherosclerotic lesion from the circulation by pressing the plaque against the vessel wall. Comparative, randomized studies in larger series of patients are needed with carotid-dedicated stent-graft designs

  16. Stent Thrombosis With Drug-Eluting Stents and Bioresorbable Scaffolds: Evidence From a Network Meta-Analysis of 147 Trials.

    Science.gov (United States)

    Kang, Si-Hyuck; Chae, In-Ho; Park, Jin-Joo; Lee, Hak Seung; Kang, Do-Yoon; Hwang, Seung-Sik; Youn, Tae-Jin; Kim, Hyo-Soo

    2016-06-27

    This study sought to perform a systematic review and network meta-analysis to compare the relative safety and efficacy of contemporary DES and BVS. To improve outcomes of patients undergoing percutaneous coronary revascularization, there have been advances in the design of drug-eluting stents (DES), including the development of drug-eluting bioresorbable vascular scaffolds (BVS). Prospective, randomized, controlled trials comparing bare-metal stents (BMS), paclitaxel-eluting stents (PES), sirolimus-eluting stents (SES), Endeavor zotarolimus-eluting stents (E-ZES), cobalt-chromium (CoCr) everolimus-eluting stents (EES), platinum-chromium (PtCr)-EES, biodegradable polymer (BP)-EES, Resolute zotarolimus-eluting stents (R-ZES), BP biolimus-eluting stents (BP-BES), hybrid sirolimus-eluting stents (H [Orsiro]-SES), polymer-free sirolimus- and probucol-eluting stents, or BVS were searched in online databases. The primary endpoint was definite or probable stent thrombosis at 1 year. A total of 147 trials including 126,526 patients were analyzed in this study. All contemporary DES were superior to BMS and PES in terms of definite or probable stent thrombosis at 1 year. CoCr-EES, PtCr-EES, and H-SES were associated with significantly lower risk than BVS. CoCr-EES and H-SES were superior to SES and BP-BES. The risk of myocardial infarction was significantly lower with H-SES than with BVS. There were no significant differences regarding all-cause or cardiac mortality. Contemporary devices including BVS showed comparably low risks of repeat revascularization. Contemporary DES, including biocompatible DP-DES, BP-DES, and polymer-free DES, showed a low risk of definite or probable stent thrombosis at 1 year. BVS had an increased risk of device thrombosis compared with CoCr-EES, PtCr-EES, and H-SES. Data from extended follow-up are warranted to confirm the long-term safety of contemporary coronary devices. Copyright © 2016 American College of Cardiology Foundation. Published by

  17. Magnetizable stent-grafts enable endothelial cell capture

    Science.gov (United States)

    Tefft, Brandon J.; Uthamaraj, Susheil; Harburn, J. Jonathan; Hlinomaz, Ota; Lerman, Amir; Dragomir-Daescu, Dan; Sandhu, Gurpreet S.

    2017-04-01

    Emerging nanotechnologies have enabled the use of magnetic forces to guide the movement of magnetically-labeled cells, drugs, and other therapeutic agents. Endothelial cells labeled with superparamagnetic iron oxide nanoparticles (SPION) have previously been captured on the surface of magnetizable 2205 duplex stainless steel stents in a porcine coronary implantation model. Recently, we have coated these stents with electrospun polyurethane nanofibers to fabricate prototype stent-grafts. Facilitated endothelialization may help improve the healing of arteries treated with stent-grafts, reduce the risk of thrombosis and restenosis, and enable small-caliber applications. When placed in a SPION-labeled endothelial cell suspension in the presence of an external magnetic field, magnetized stent-grafts successfully captured cells to the surface regions adjacent to the stent struts. Implantation within the coronary circulation of pigs (n=13) followed immediately by SPION-labeled autologous endothelial cell delivery resulted in widely patent devices with a thin, uniform neointima and no signs of thrombosis or inflammation at 7 days. Furthermore, the magnetized stent-grafts successfully captured and retained SPION-labeled endothelial cells to select regions adjacent to stent struts and between stent struts, whereas the non-magnetized control stent-grafts did not. Early results with these prototype devices are encouraging and further refinements will be necessary in order to achieve more uniform cell capture and complete endothelialization. Once optimized, this approach may lead to more rapid and complete healing of vascular stent-grafts with a concomitant improvement in long-term device performance.

  18. Impact on outcome of different types of carotid stent: results from the European Registry of Carotid Artery Stenting.

    Science.gov (United States)

    Stabile, Eugenio; Giugliano, Giuseppe; Cremonesi, Alberto; Bosiers, Marc; Reimers, Bernhard; Setacci, Carlo; Cao, Piergiorgio; Schmidt, Andrej; Sievert, Horst; Peeters, Patrick; Nikas, Dimitrios; Sannino, Anna; de Donato, Gianmarco; Parlani, Giambattista; Castriota, Fausto; Hornung, Marius; Rubino, Paolo; Esposito, Giovanni; Tesorio, Tullio

    2016-06-12

    Conflicting data exist on the impact on outcome of the use of different stent types during carotid artery stenting (CAS). The aim of this study was to evaluate clinical outcomes according to different carotid stent design among the population of the European Registry of Carotid Artery Stenting (ERCAS). The present study was conducted in 1,604 patients who underwent neuroprotected CAS in ERCAS. All types of commercially available carotid stent were used. Open-cell design stents were classified according to free cell area into 7.5 mm2. A total of 713 closed-cell, 456 hybrid-cell, 238 7.5 mm2 open-cell stents were implanted. Overall, the 30-day stroke and death rate was 1.37%. At 30 days, 19 strokes occurred (1.18%): eight in the group of patients treated with a closed-cell (1.12%), two in those with a hybrid-cell (0.44%), three in those with a 7.5 mm2 open-cell stent (3.05%) (p=0.045). Data of the present study suggest that, in the setting of neuroprotected CAS performed in high-volume centres by properly trained operators, the use of an open-cell design stent with a free cell area >7.5 mm2 may be associated with an increased 30-day stroke risk.

  19. Investigation of adverse events associated with an off-label use of arterial stents and CE-marked iliac vein stents in the iliac vein: insights into developing a better iliac vein stent.

    Science.gov (United States)

    Shida, Takuya; Umezu, Mitsuo; Iwasaki, Kiyotaka

    2018-06-01

    We analyzed the adverse events associated with an off-label use of arterial stents and CE-marked iliac vein stents for the treatment of iliac venous thromboembolism and investigated their relationships with the anatomical features of the iliac vein, to gain insights into the development of a better iliac vein stent. Reports of adverse events following the use of stents in the iliac vein were retrieved from the Manufacturer and User Facility Device Experience (MAUDE) database that contain suspected device-associated complications reported to the Food and Drug Administration. Data from 2006 to 2016 were investigated. The literature analysis was also conducted using PubMed, Cochrane Library, EMBASE, and Web of Science focusing on English articles published up to 4 October 2016. The analysis of 88 adverse events from the MAUDE database and 182 articles from the literature revealed that a higher number of adverse events had been reported following the use of arterial stents in the iliac vein compared to CE-marked iliac vein stents. While stent migration and shortening were reported only for the arterial stents, stent fracture and compression occurred regardless of the stent type, even though a vein does not pulsate. A study of the anatomical features of the iliac vein implies that bending, compression, and kink loads are applied to the iliac vein stents in vivo. For designing, developing, and pre-clinical testing of stents intended for use in the iliac vein, the above mechanical load environments induced by the anatomical features should be considered.

  20. Acute ST-Elevation Myocardial Infarction after Coronary Stent Fracture.

    Science.gov (United States)

    Rafighdust, Abbasali; Eshraghi, Ali

    2015-10-27

    The invention of the drug-eluting stent (DES) has brought about revolutionary changes in the field of interventional cardiology. In the DES era, in-stent restenosis has declined but new issues such as stent thrombosis have emerged. One of the emerging paradigms in the DES era is stent fracture. There are reports about stent fracture leading to in-stent restenosis or stent thrombosis. Most of these reports concern the Sirolimus-eluting stent. The present case is a representation of a Biolimus-eluting stent fracture. We introduce a 64-year-old male patient, for whom the BioMatrix stent was deployed in the right coronary artery. Five months after the implantation, he experienced acute myocardial infarction, with stent fracture leading to stent thrombosis being the causative mechanism. Another DES (Cypher) was used to manage this situation, and the final result was good.

  1. Nitinol Esophageal Stents: New Designs and Clinical Indications

    International Nuclear Information System (INIS)

    Strecker, Ernst-Peter; Boos, Irene; Vetter, Sylvia; Strohm, Michael; Domschke, Sigurd

    1996-01-01

    Purpose: To evaluate the clinical use of covered and noncovered, knitted nitinol stents in patients presenting new stent indications. Methods: Self-expandable, knitted nitinol stents were implanted in four patients for treatment of dysphagia. In two patients who had malignant strictures and had esophago-respiratory fistulae and in one patient with an esophagocutaneous fistula, polytetrafluoroethylene (PTFE)-covered stents were implanted. One patient received a noncovered stent, but a retrograde approach through a percutaneous endoscopic gastrostomy (PEG) fistula had to be chosen for recanalization of an esophageal occlusion. Two patients received stents for treatment of benign strictures. Results: Recanalization of the stricture and stent implantation were performed under fluoroscopic control without any procedure-related morbidity or mortality. Dysphagia improved in all patients and the esophageal fistulae could be sealed off by covered stents. During a maximum follow-up of 18 months, there was no stent migration or esophageal perforation. Complications observed were stent stenosis due to food impaction (1/4) and benign stent stenosis (2/2). Most complications could be treated by the interventional radiologist. Conclusion: Self-expandable, covered Nitinol stents provide an option for the treatment of dysphagia combined with esophageal fistulae. In combination with interventional radiology techniques, even complex strictures are accessible. For benign strictures, the value of stent treatment has not yet been proven

  2. Serial Versus Direct Dilation of Small Diameter Stents Results in a More Predictable and Complete Intentional Transcatheter Stent Fracture: A PICES Bench Testing Study.

    Science.gov (United States)

    Crystal, Matthew A; Morgan, Gareth J; Danon, Saar; Gray, Robert G; Gruenstein, Daniel H; Gordon, Brent M; Goldstein, Bryan H

    2018-01-01

    Balloon-expandable stents, implanted in infants and children with congenital heart disease (CHD), often require redilation to match somatic growth. Small diameter stents may eventually require longitudinal surgical transection to prevent iatrogenic vascular stenosis. Intentional transcatheter stent fracture (TSF) is an emerging alternative approach to stent transection, but little is known about the optimal stent substrate and best protocol to improve the likelihood of successful TSF. Bench testing was performed with a stent dilation protocol. After recording baseline characteristics, stents were serially or directly dilated using ultra-high-pressure balloons (UHPB) until fracture occurred or further stent dilation was not possible. Stent characteristics recorded were as follows: cell design, metallurgy, mechanism, and uniformity of fracture. Stents tested included bare-metal coronary stents, premounted small diameter stents, and ePTFE-covered small diameter premounted stents. Ninety-four stents representing 9 distinct models were maximally dilated, with 80 (85%) demonstrating evidence of fracture. Comprehensive fracture details were recorded in 64 stents: linear and complete in 34/64 stents (53.1%), linear and incomplete in 9/64 stents (14.1%), transverse/complex and complete in 6/64 stents (9.4%), and transverse/complex and incomplete in 15/64 stents (23.4%). Stent fracture was not accomplished in some stent models secondary to significant shortening, i.e., "napkin-ring" formation. Serial dilation resulted in evidence of fracture in 62/67 (92.5%) stents compared with 18/27 (66.7%) stents in the direct dilation group (p = 0.003). Intentional TSF is feasible in an ex vivo model. Serial dilation more reliably expanded the stent and allowed for ultimate stent fracture, whereas direct large diameter dilation of stents was more likely to generate a "napkin-ring" configuration, which may be more resistant to fracture. In vivo animal and human testing is necessary to

  3. Anchoring barbs and balloon expandable stents: what is the risk of perforation and failed stent deployment?

    Science.gov (United States)

    Bown, M J; Harrison, G J; How, T V; Brennan, J A; Fisher, R K; Vallabhaneni, S R; McWilliams, R G

    2012-09-01

    Balloon expandable stents may on occasion be deployed in close proximity to the anchoring barbs of endovascular grafts. The aim of this study was to determine the risk and effect of balloon perforation by anchoring barbs and to assess whether these risks are different if the balloon is protected by a covered stent mounted upon it. A bench-top model was developed to mimic the penetration of anchoring barbs into the lumen of medium sized blood vessels. The model allowed variation of angle and depth of vessel penetration. Both bare balloons and those with covered stents mounted upon them were tested in the model to determine whether there was a risk of perforation and which factors increased or decreased this risk. All combinations of barb angle and depth caused balloon perforation but this was most marked when the barb was placed perpendicular to the long axis of the balloon. When the deployment of covered stents was attempted balloon perforation occurred in some cases but full stent deployment was achieved in all cases where the perforation was in the portion of the balloon covered by the stent. The only situation in which stent deployment failed was where the barb was intentionally placed in the uncovered portion of the balloon. This resulted in only partial deployment of the stent. Balloon rupture is a distinct possibility when deploying balloon-expandable stents in close proximity to anchoring barbs. Care should be taken in this circumstance to ensure that the barb is well away from the uncovered portion of the balloon. Copyright © 2012 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.

  4. The impact of precise robotic lesion length measurement on stent length selection: ramifications for stent savings.

    Science.gov (United States)

    Campbell, Paul T; Kruse, Kevin R; Kroll, Christopher R; Patterson, Janet Y; Esposito, Michele J

    2015-09-01

    Coronary stent deployment outcomes can be negatively impacted by inaccurate lesion measurement and inappropriate stent length selection (SLS). We compared visual estimate of these parameters to those provided by the CorPath 200® Robotic PCI System. Sixty consecutive patients who underwent coronary stent placement utilizing the CorPath System were evaluated. The treating physician assessed orthogonal images and provided visual estimates of lesion length and SLS. The robotic system was then used for the same measures. SLS was considered to be accurate when visual estimate and robotic measures were in agreement. Visual estimate SLSs were considered to be "short" or "long" if they were below or above the robotic-selected stents, respectively. Only 35% (21/60) of visually estimated lesions resulted in accurate SLS, whereas 33% (20/60) and 32% (19/60) of the visually estimated SLSs were long and short, respectively. In 5 cases (8.3%), 1 less stent was placed based on the robotic lesion measurement being shorter than the visual estimate. Visual estimate assessment of lesion length and SLS is highly variable with 65% of the cases being inaccurately measured when compared to objective measures obtained from the robotic system. The 32% of the cases where lesions were visually estimated to be short represents cases that often require the use of extra stents after the full lesion is not covered by 1 stent [longitudinal geographic miss (LGM)]. Further, these data showed that the use of the robotic system prevented the use of extra stents in 8.3% of the cases. Measurement of lesions with robotic PCI may reduce measurement errors, need for extra stents, and LGM. Copyright © 2015 Elsevier Inc. All rights reserved.

  5. [Developments in percutaneous coronary intervention and coronary stents].

    Science.gov (United States)

    Simsek, C; Daemen, J; Zijlstra, F

    2014-01-01

    In The Netherlands, more than 30.000 patients undergo a percutaneous coronary intervention every year, during which a coronary stent implantation will be performed in 90% of the cases. It is estimated that more than 5 million coronary stent implantations will be performed worldwide this year. While these numbers are impressive, however, coronary stents still have as a limitation the possibility of stent thrombosis. This has been and is an important stimulus for the development of both coronary stents, from a bare metal stent via a drug eluting stent to the present-day development of bio-absorbable stents, and anti-platelet drugs,from acenocoumarol to thieropyridines. The possibility of shortening the period of use of this powerful medication by developing new kinds of non-thrombogenic stents would, for example, make it possible to achieve significant reductions in subsequent bleeding during (dental) procedures.

  6. Polymeric Biodegradable Stent Insertion in the Esophagus

    Directory of Open Access Journals (Sweden)

    Kai Yang

    2016-04-01

    Full Text Available Esophageal stent insertion has been used as a well-accepted and effective alternative to manage and improve the quality of life for patients diagnosed with esophageal diseases and disorders. Current stents are either permanent or temporary and are fabricated from either metal or plastic. The partially covered self-expanding metal stent (SEMS has a firm anchoring effect and prevent stent migration, however, the hyperplastic tissue reaction cause stent restenosis and make it difficult to remove. A fully covered SEMS and self-expanding plastic stent (SEPS reduced reactive hyperplasia but has a high migration rate. The main advantage that polymeric biodegradable stents (BDSs have over metal or plastic stents is that removal is not require and reduce the need for repeated stent insertion. But the slightly lower radial force of BDS may be its main shortcoming and a post-implant problem. Thus, strengthening support of BDS is a content of the research in the future. BDSs are often temporarily effective in esophageal stricture to relieve dysphagia. In the future, it can be expect that biodegradable drug-eluting stents (DES will be available to treat benign esophageal stricture, perforations or leaks with additional use as palliative modalities for treating malignant esophageal stricture, as the bridge to surgery or to maintain luminal patency during neoadjuvant chemoradiation.

  7. Flexibility and trackability of laser cut coronary stent systems.

    Science.gov (United States)

    Szabadíts, Péter; Puskás, Zsolt; Dobránszky, János

    2009-01-01

    Coronary stents are the most important supports in present day cardiology. Flexibility and trackability are two basic features of stents. In this paper, four different balloon-expandable coronary stent systems were investigated mechanically in order to compare their suitability. The coronary stent systems were assessed by measurements of stent flexibility as well as by comparison of forces during simulated stenting in a self-investigated coronary vessel model. The stents were cut by laser from a single tube of 316L stainless steel or L-605 (CoCr) cobalt chromium alloy. The one-and four-point bending tests were carried out to evaluate the stent flexibility E x I (Nmm(2)), under displacement control in crimped and expanded configurations. The flexibility of stents would be rather dependent on the design than on raw material. In general a more flexible stent needs lower tracking force during the implantation. The L-605 raw material stents need lower track force to pass through in the vessel model than the 316L raw material stents. The sort and long stents passed through the curved vessel model in different ways. The long stents nestled to the vessel wall at the outer arc and bent, while the short stents did not bend in the curve, only the delivery systems bent.

  8. Comparison of diamond-like carbon-coated nitinol stents with or without polyethylene glycol grafting and uncoated nitinol stents in a canine iliac artery model

    Science.gov (United States)

    Kim, J H; Shin, J H; Shin, D H; Moon, M-W; Park, K; Kim, T-H; Shin, K M; Won, Y H; Han, D K; Lee, K-R

    2011-01-01

    Objective Neointimal hyperplasia is a major complication of endovascular stent placement with consequent in-stent restenosis or occlusion. Improvements in the biocompatibility of stent designs could reduce stent-associated thrombosis and in-stent restenosis. We hypothesised that the use of a diamond-like carbon (DLC)-coated nitinol stent or a polyethylene glycol (PEG)-DLC-coated nitinol stent could reduce the formation of neointimal hyperplasia, thereby improving stent patency with improved biocompatibility. Methods A total of 24 stents were implanted, under general anaesthesia, into the iliac arteries of six dogs (four stents in each dog) using the carotid artery approach. The experimental study dogs were divided into three groups: the uncoated nitinol stent group (n = 8), the DLC-nitinol stent group (n = 8) and the PEG-DLC-nitinol stent group (n = 8). Results The mean percentage of neointimal hyperplasia was significantly less in the DLC-nitinol stent group (26.7±7.6%) than in the nitinol stent group (40.0±20.3%) (p = 0.021). However, the mean percentage of neointimal hyperplasia was significantly greater in the PEG-DLC-nitinol stent group (58.7±24.7%) than in the nitinol stent group (40.0±20.3%) (p = 0.01). Conclusion Our findings indicate that DLC-coated nitinol stents might induce less neointimal hyperplasia than conventional nitinol stents following implantation in a canine iliac artery model; however, the DLC-coated nitinol stent surface when reformed with PEG induces more neointimal hyperplasia than either a conventional or DLC-coated nitinol stent. PMID:21325363

  9. Temporary urethral covered stent - third year of experience

    International Nuclear Information System (INIS)

    Stojanovis, V.; Maksimovis, H.; Markovis, B.; Markovis, Z.

    2006-01-01

    Full text: In October 2003, a new generation of urethral stents ALLIUM, produced in Israel, were used at the Department of Interventional Radiology, CCS, in 18 patients with chronic stricture of bulbar urethra. The indications for insertion were determined according to well-known and recognized therapeutical protocols. The stent is made of nitinol wire with polyurethane cover. It is inserted under local anesthesia by a special self-expandable system that may be fixed or flexible. The stents we used were 3-6 cm long and 28 Fr wide. Radioscopic-assisted insertion was performed over formerly placed metal guide. Prior to insertion, balloon-catheter dilatation of stricture matching the stent width was carried out. Pre-insertion urethrotomy was performed in one case. The insertion technique is simple, presupposing the knowledge of older generations of techniques of urethral dilatation and insertion of self-expandable stents. The follow-up of results was done according to a priori established protocol including the following: UCG, uroflowmetry and interview with patients. Due to stent migration, the 'stent over stent' technique was applied in one case, while reposition by balloon-catheter outward traction was performed in two cases of caudal migration. No irritative discomforts were reported in the first 4 months after stent dwelling. Uroflowmetric controls verified at least four times better results than before the insertion. Given it is the question of covered stent, there is no possibility of proliferative secondary lumen obstruction. On account of soft structure and conic shape of posterior part of stent, no lesions of the external urethral sphincter were manifested. The stent is simply withdrawn after 6 months by outward traction using the forceps at the time when the stent construction turns into soft and straight wire. The first clinical experiences are very favorable and ALLIUM stent may be expected to be the stent of choice for chronic bulbar strictures

  10. The effect of stent structure changes on the hemodynamics and the formation of in-stent restenosis

    International Nuclear Information System (INIS)

    Wu Xia; Xu Ke; Xiao Liang; Zhang Xitong; Su Hongying; Feng Bo

    2009-01-01

    Objective: To investigate the effect of stent structure changes on the formation of in-stent restenosis by studying the influence of these changes on the shear force to the vascular wall, on the velocity of flow and on the flow pattern. Methods: Five stent models were established by using Pro/engineer wildfire 3.0. Model A was regarded as control structure. On the base structure of model A, transverse link component was added to form model B, and vertical link component was added to form model C. The thickness of model D was twice than that of model A, and the meshes density of model E was twice than that of model A. Fluid models were built up by importing these stent models into computational fluid dynamics (CFD) software ansys11.0-CFX, then, CFD analysis was proceeded to study the effect of stent structure on hemodynamics. Results: After the stents were implanted, the percentage of low wall shear stress on the surface of model A, B, C, D and E was 7.78%, 6.65%, 1.48%, 16.52% and 12.12%, respectively. The percentage of D and E was obviously larger than that of A, while the percentage of B was markedly smaller than that of A. The velocity vector on the cross-sectional planes showed that the low velocity and eddy areas in D and E were much larger than that in A, while this area in C was smaller than that in A. Conclusion: The stent structure changes can cause obvious changes in hemodynamics in the implanted vessels. The increase in the thickness and meshes density of the stent is the main factor that induces the formation of low wall shear stress, which will precipitate the development of in-stent restenosis. The added vertical link component will reduce the area of low wall shear stress as well as the occurrence of in-stent restenosis. (authors)

  11. Gianturco-Rösch Z stents in tracheobronchial stenoses.

    Science.gov (United States)

    Petersen, B D; Uchida, B T; Barton, R E; Keller, F S; Rösch, J

    1995-01-01

    To evaluate expandable metallic Gianturco-Rösch Z (GRZ) stents for treatment of benign and malignant tracheobronchial stenoses. Six patients, ages 45-73 years, were treated for severe dyspnea with placement of GRZ stents. Three patients had benign tracheal lesions (one tracheomalacia, two postoperative) and received uncovered GRZ stents. Three patients had malignant stenoses at the level of the carina; one received an uncovered stent and the other two received silicone-covered GRZ stents. Two patients with benign lesions responded well to stent placement. One was asymptomatic for a year and then was lost to follow-up; the other improved substantially but died of end-stage lung disease 5 months after stent placement. A third patient with a benign high tracheal lesion did poorly; symptoms recurred secondary to inferior migration of a stent, which was removed surgically at 4 months. All patients with malignant lesions improved symptomatically after stent placement and remained without significant dyspnea until death (from 1 to 6 months). Expandable GRZ stents are promising devices for treatment of benign lesions and offer effective palliation of malignant tracheobronchial stenoses.

  12. Insertion of Self-Expandable Nitinol Stents Without Previous Balloon Angioplasty Reduces Restenosis Compared with PTA Prior to Stenting

    International Nuclear Information System (INIS)

    Harnek, Jan; Zoucas, Evita; Stenram, Unne; Cwikiel, Wojciech

    2002-01-01

    Purpose: To compare the development of intimal hyperplasia after deployment of a self-expanding nitinol stent with and without previous percutaneous transluminal balloon angioplasty (PTA), with the results after PTA alone. Methods: In nine healthy pigs, the iliac arteries were divided into three groups: group 1 (n = 6 arteries) was treated with PTA; group 2 n 6)with insertion of self-expanding stents after PTA; and group 3 (n = 6) with stent insertion without previous PTA. After 8 weeks the vessels were examined with intravascular ultrasonography,histologic examination and morphometric analysis. Results: Although the injury index in group 1 (0.17± 0.57) was lower (p <0.05) than in group 2 (0.26 ± 0.06) and group 3 (0.26 ± 0.08), PTA-treated arteries showed significantly (p <0.05) reduced mean luminal gain (0.53 ± 2.84) compared with arteries treated with PTA prior to stenting (2.58 ± 1.38) and compared with stenting alone (4.65 ±5.34). Stenting after PTA resulted in a higher (p<0.05) restenosis index (2.63 ± 1.06) compared with stenting without PTA (1.35 ± 0.59). Group 2 also had a significantly thicker intimap <0.05) and 83% and 74% higher intima/mediaratio (p <0.05) compared with groups 1 and 3, respectively. Conclusion: Insertion of a self-expandable nitinol stent without previous PTA results in less intimalhyperplasia than if PTA is performed prior to stenting, suggesting that direct stenting can be used in angioplasty sessions with a favorable outcome

  13. Mechanical thrombectomy using Rotarex system and stent-in-stent placement for treatment of distal femoral artery occlusion secondary to stent fracture – a case report and literature review

    International Nuclear Information System (INIS)

    Dys, Krzysztof; Drelichowska-Durawa, Justyna; Dołega-Kozierowski, Bartosz; Lis, Michał; Sokratous, Kyriakos; Iwanowski, Wojciech; Drelichowski, Stanisław; Witkiewicz, Wojciech

    2013-01-01

    Treatment of peripheral arterial diseases may be distinguished into conservative and interventional management; the latter is divided into surgical and endovascular procedures. Management of peripheral artery stenosis and occlusion with vascular stents is associated with the risk of late complications such as restenosis, stent fracture or dislocation. A 62-year-old woman with generalized atherosclerosis, particularly extensive in lower limb arteries, was admitted to the Department of Angiology 11 months after having an endovascular procedure performed due to critical ischemia of left lower limb. Because of stent occlusion, a decision to perform angiographic examination of lower limb arteries was made. Examination revealed occlusion of the superficial femoral artery along its entire length, including previously implanted stents. Distal stent was fractured with slight dislocation of the proximal segment. A decision was made to perform mechanical thrombectomy using a Rotarex system followed by a stent-in-stent placement procedure. Follow-up angiography and ultrasound scan performed 24 hours after the procedure revealed a patent vessel with satisfactory blood flow. Nowadays, imaging diagnostics of peripheral artery stenosis involves non-invasive examinations such as ultrasound, minimally invasive examinations such as angio-MRI and MDCT, or invasive examinations such as DSA and IVUS. DSA examinations are used to confirm significant stenosis or occlusion of a vessel, particularly when qualifying a patient for endovascular treatment. Due to their anatomic location, the superficial femoral artery and the popliteal artery are subject to various forces e.g. those exerted by the working muscles. Mechanical thrombectomy and atherectomy are efficient methods of arterial recanalization used in the treatment of acute, subacute or even chronic occlusions or stenosis of peripheral vessels. Frequency of angioplasty and vascular stent implantation procedures is increased in patients

  14. Drug-eluting stents appear superior to bare metal stents for vein-graft PCI in vessels up to a stent diameter of 4 mm

    Directory of Open Access Journals (Sweden)

    Oliver P. Guttmann

    2016-05-01

    Full Text Available BackgroundResearch trials have shown improved short-term outcome with drug-eluting stents (DES over bare metal stents (BMS in saphenous vein graft (SVG percutaneous coronary intervention (PCI, primarily by reducing target vessel revascularization (TVR for in-stent restenosis. We compared the outcomes in patients undergoing SVG stent implantation treated with DES or BMS. In exploratory analyses we investigated the influence of stent generation and diameter.MethodsData were obtained from a prospective database of 657 patients who underwent PCI for SVG lesions between 2003 and 2011. A total of 344 patients had PCI with BMS and 313 with DES. Propensity scores were developed based on 15 observed baseline covariates in a logistic regression model with stent type as the dependent variable. The nearest-neighbour-matching algorithm with Greedy 5-1 Digit Matching was used to produce two patient cohorts of 313 patients each. We assessed major adverse cardiac events (MACE out to a median of 3.3 years (interquartile range: 2.1-4.1. MACE was defined as all-cause mortality, myocardial infarction (MI, TVR and stroke.ResultsThere was a significant difference in MACE between the two groups in favour of DES (17.9% DES vs. 31.2% BMS group; p = 0.0017 over the 5-year follow-up period. MACE was driven by increased TVR in the BMS group. There was no difference in death, MI or stroke. Adjusted Cox analysis confirmed a decreased risk of MACE for DES compared with BMS 0.75 (95% confidence interval (CI 0.52-0.94, with no difference in the hazard of all-cause mortality (hazard ratio: 1.08; 95% CI: 0.77-1.68. However, when looking at stent diameters greater than 4 mm, no difference was seen in MACE rates between BMS and DES.ConclusionsOverall in our cohort of patients who had PCI for SVG disease, DES use resulted in lower MACE rates compared with BMS over a 5-year follow-up period; however, for stent diameters over 4 mm no difference in MACE rates was seen.

  15. Direct coronary stenting in reducing radiation and radiocontrast consumption

    International Nuclear Information System (INIS)

    Caluk, Jasmin; Osmanovic, Enes; Barakovic, Fahir; Kusljugic, Zumreta; Terzic, Ibrahim; Caluk, Selma; Sofic, Amela

    2010-01-01

    Coronary stenting is the primary means of coronary revascularization. There are two basic techniques of stent implantation: stenting with balloon predilatation of stenosis and stenting without predilatation (direct stenting). Limiting the time that a fluoroscope is activated and by appropriately managing the intensity of the applied radiation, the operator limits radiation in the environment, and this saves the exposure to the patient and all personnel in the room. Nephrotoxicity is one of the most important properties of radiocontrast. The smaller amount of radiocontrast used also provides multiple positive effects, primarily regarding the periprocedural risk for the patients with the reduced renal function. The goal of the study was to compare fluoroscopy time, the amount of radiocontrast, and expenses of material used in direct stenting and in stenting with predilatation. In a prospective study, 70 patients with coronary disease were randomized to direct stenting, or stenting with predilatation. Fluoroscopy time and radiocontrast use were significantly reduced in the directly stented patients in comparison to the patients stented with balloon-predilatation. The study showed a significant reduction of expenses when using a direct stenting method in comparison to stenting with predilatation. If the operator predicts that the procedure can be performed using direct stenting, he is encouraged to do so. Direct stenting is recommended for all percutaneous coronary interventions when appropriate conditions have been met. If direct stenting has been unsuccessful, the procedure can be converted to predilatation

  16. In vivo evaluation of axial integrity of coronary stents using intravascular ultrasound: Insights on longitudinal stent deformation.

    Science.gov (United States)

    Dvir, Danny; Kitabata, Hironori; Barbash, Israel M; Minha, Sa'ar; Badr, Salem; Loh, Joshua P; Chen, Fang; Torguson, Rebecca; Waksman, Ron

    2014-09-01

    To evaluate the axial integrity of different coronary stents using intravascular ultrasound (IVUS). Longitudinal stent deformation was recently reported. Consecutive patients who underwent IVUS analysis after drug-eluting stent (DES) implantation for de novo coronary lesions were evaluated. Stent length was compared with label length for calculation of absolute change and relative difference (absolute change divided by label length). A total of 233 DES utilizing five different platforms were included. The median absolute change in stent length was 0.90 mm (interquartile range [IQR] 0.48-1.39) and the relative difference was 5.24% (IQR 2.55-8.29). There was no significant difference among the groups in median absolute or relative change: Cypher 0.89 mm/3.89%, Taxus 0.88 mm/5.39%, Endeavor 1.16 mm/6.77%, Xience V 0.86 mm/5.80%, and PROMUS Element 0.79 mm/5.34% (P = 0.085, P = 0.072, respectively). Multivariate logistic regression revealed that the Cypher stent was independently correlated with a lower change in length, whereas stent label length and deployment pressure were correlated with higher absolute change. The axial integrity of DES platforms examined in vivo was high, with only mild changes in stent length after implantation. While there are differences between first- and second-generation DES, axial integrity among second-generation DES was similar. © 2013 Wiley Periodicals, Inc.

  17. Scintigraphic examinations after stent implantation in central airways; Szintigraphische Untersuchungen bei Stents in den zentralen Atemwegen

    Energy Technology Data Exchange (ETDEWEB)

    Richter, W.S.; Kettner, B.I.; Munz, D.L. [Klinik und Poliklinik fuer Nuklearmedizin, Universitaetsklinikum Charite, Medizinische Fakulteat der Humboldt-Univ. zu Berlin (Germany)

    1998-03-01

    Endotracheal and endobronchial stent implantation has been developed as an effective treatment of benign and malignant airway stenosis and of tracheo- or bronchoesophageal fistulas. The selection of the stent type depends on the kind and site of disease. Chest X-ray and bronchoscopy are the procedures of choice for monitoring of stent position, structure, and function. However, with scintigraphic methods the effects of stent implantation on pulmonary ventilation and perfusion can be assessed non-invasively. The validation of the effect of a stent implantation on mucociliary and tussive clearance remains to be elucidated. (orig.) [Deutsch] Die endotracheale und -bronchiale Stentimplantation wurde in den letzten Jahren als effektive Massnahme bei benignen und malignen Stenosen der Atemwege, drohendem Atemwegsverschluss und bei tracheo- bzw. bronchooesophagealen Fisteln eingefuehrt. Der gewaehlte Stenttyp richtet sich nach dem Implantationsort und den krankheitsbedingten Veraenderungen. Zum Monitoring von Lage, Struktur und Funktion eines Stents dienen Thoraxroentgenaufnahmen und die Bronchoskopie. Nuklearmedizinische Verfahren koennen nicht-invasiv den Effekt der Stenteinlage auf Lungenventilation und -perfusion belegen. Die Validierung des Effekts einer Stentimplantation auf die mukoziliaere und tussive Clearance steht noch aus. (orig.)

  18. Efficacy of different types of self-expandable stents in carotid artery stenting for carotid bifurcation stenosis.

    Science.gov (United States)

    Liu, Ya-min; Qin, Hao; Zhang, Bo; Wang, Yu-jing; Feng, Jun; Wu, Xiang

    2016-02-01

    Both open and closed loop self-expandable stents were used in carotid artery stenting (CAS) for carotid bifurcation stenosis. We sought to compare the efficacy of two types of stents in CAS. The data of 212 patients treated with CAS (42 and 170 cases implanted with closed and open loop stents, respectively) for carotid bifurcation stenosis and distal filtration protection devices were retrospectively analyzed. Between closed and open loop stents, there were no significant differences in hospitalization duration, NIHSS score before and after the treatment, stenosis at 12th month, and cumulative incidence of primary endpoint events within 30 days or from the 31st day to the 12th month; while there were significant differences in hemodynamic changes and rate of difficulty in recycling distal filtration protection devices. Use of open vs. closed loop stents for carotid bifurcation stenosis seems to be associated with similar incidence of complications, except for greater rate of hemodynamic changes and lower rate of difficulty in recycling the distal filtration protection devices.

  19. Clinical application of hepatic vein percutaneous transluminal angioplasty and stent after stent placement in inferior vena cava

    International Nuclear Information System (INIS)

    Xu Hao; Zu Maoheng; Gu Yuming; Li Guojun; Zhang Qingqiao; Wei Ning; Xu Wei; Liu Hongtao

    2005-01-01

    Objective: To investigate the feasibility and effect of recanalization of hepatic vein with percutaneous transluminal angioplasty (PTA) and stent after stent placement in inferior vena cava (IVC). Methods: Eleven patients with Budd-Chiari syndrome (BCS)were once performed metal stent placement in IVC at other hospital, but ascites was not subsided in 9 patients after the stent placement and occurred again in 2 patients in 3 months after the procedure. PTA and metal stent placement were used to treat the occlusion of the hepatic vein (HV) via stent in IVC. Results: Recanalization of occlusive HV was successful in all 11 patients, and symptoms disappeared or were obviously improved. The mean blood pressure in HV dropped from pre-operation (45.12 ± 1.57) cm H 2 O (1 cm H 2 O=0.098 kPa) to post-operation (17.53 ± 0.68) cm H 2 O (P<0.01). In a period of 4-30 months (mean: 13.6 months) following-up, no patient reoccurred symptoms. Conclusion: Recanalization of HV via stent in IVC is a feasible and effective method for occlusive HV, but it is difficult. (authors)

  20. Semi-Automatic Electronic Stent Register: a novel approach to preventing ureteric stents lost to follow up.

    Science.gov (United States)

    Macneil, James W H; Michail, Peter; Patel, Manish I; Ashbourne, Julie; Bariol, Simon V; Ende, David A; Hossack, Tania A; Lau, Howard; Wang, Audrey C; Brooks, Andrew J

    2017-10-01

    Ureteric stents are indispensable tools in modern urology; however, the risk of them not being followed-up once inserted poses medical and medico-legal risks. Stent registers are a common solution to mitigate this risk; however, manual registers are logistically challenging, especially for busy units. Western Sydney Local Health District developed a novel Semi-Automatic Electronic Stent Register (SAESR) utilizing billing information to track stent insertions. To determine the utility of this system, an audit was conducted comparing the 6 months before the introduction of the register to the first 6 months of the register. In the first 6 months of the register, 457 stents were inserted. At the time of writing, two of these are severely delayed for removal, representing a rate of 0.4%. In the 6 months immediately preceding the introduction of the register, 497 stents were inserted, and six were either missed completely or severely delayed in their removal, representing a rate of 1.2%. A non-inferiority analysis found this to be no worse than the results achieved before the introduction of the register. The SAESR allowed us to improve upon our better than expected rate of stents lost to follow up or severely delayed. We demonstrated non-inferiority in the rate of lost or severely delayed stents, and a number of other advantages including savings in personnel costs. The semi-automatic register represents an effective way of reducing the risk associated with a common urological procedure. We believe that this methodology could be implemented elsewhere. © 2017 Royal Australasian College of Surgeons.

  1. Basic Knowledge about Metal Stent Development

    Directory of Open Access Journals (Sweden)

    Seok Jeong

    2016-03-01

    Full Text Available Biliary self-expandable metal stents (SEMS, a group of non-vascular stents, have been used in the palliative management of biliary obstruction around the world. However, there are still unmet needs in the clinical application of biliary SEMS. Comprehensive understanding of the SEMS is required to resolve the drawbacks and difficulties of metal stent development. The basic structure of SEMS, including the materials and knitting methods of metal wires, covering materials, and radiopaque markers, are discussed in this review. What we know about the physical and mechanical properties of the SEMS is very important. With an understanding of the basic knowledge of metal stents, hurdles such as stent occlusion, migration, and kinking can be overcome to develop more ideal SEMS.

  2. Prevention of stent thrombosis: challenges and solutions

    Science.gov (United States)

    Reejhsinghani, Risheen; Lotfi, Amir S

    2015-01-01

    Stent thrombosis is an uncommon but serious complication which carries with it significant mortality and morbidity. This review analyzes the entity of stent thrombosis from a historical and clinical perspective, and chronicles the evolution of this condition through the various generations of stent development, from bare metal to first-generation, second-generation, and third-generation drug-eluting stents. It also delineates the specific risk factors associated with stent thrombosis and comprehensively examines the literature related to each of these risks. Finally, it highlights the preventative strategies that can be garnered from the existing data, and concludes that a multifactorial approach is necessary to combat the occurrence of stent thrombosis, with higher risk groups, such as patients with ST segment elevation myocardial infarction, meriting further research. PMID:25657588

  3. 21 CFR 876.4620 - Ureteral stent.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ureteral stent. 876.4620 Section 876.4620 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Surgical Devices § 876.4620 Ureteral stent. (a) Identification. A ureteral stent...

  4. Stents: Biomechanics, Biomaterials, and Insights from Computational Modeling.

    Science.gov (United States)

    Karanasiou, Georgia S; Papafaklis, Michail I; Conway, Claire; Michalis, Lampros K; Tzafriri, Rami; Edelman, Elazer R; Fotiadis, Dimitrios I

    2017-04-01

    Coronary stents have revolutionized the treatment of coronary artery disease. Improvement in clinical outcomes requires detailed evaluation of the performance of stent biomechanics and the effectiveness as well as safety of biomaterials aiming at optimization of endovascular devices. Stents need to harmonize the hemodynamic environment and promote beneficial vessel healing processes with decreased thrombogenicity. Stent design variables and expansion properties are critical for vessel scaffolding. Drug-elution from stents, can help inhibit in-stent restenosis, but adds further complexity as drug release kinetics and coating formulations can dominate tissue responses. Biodegradable and bioabsorbable stents go one step further providing complete absorption over time governed by corrosion and erosion mechanisms. The advances in computing power and computational methods have enabled the application of numerical simulations and the in silico evaluation of the performance of stent devices made up of complex alloys and bioerodible materials in a range of dimensions and designs and with the capacity to retain and elute bioactive agents. This review presents the current knowledge on stent biomechanics, stent fatigue as well as drug release and mechanisms governing biodegradability focusing on the insights from computational modeling approaches.

  5. A novel, ring-connected stent versus conventional GI stents: comparative study of physical properties and migration rates in a canine colon obstruction model.

    Science.gov (United States)

    Park, Hong Suk; Choo, In Wook; Seo, Soowon; Hyun, Dongho; Lim, Sooyoun; Kim, Jae J; Hong, Saet-Byul; Min, Byung-Hoon; Do, Young Soo; Choo, Sung Wook; Shin, Sung Wook; Park, Kwang Bo; Cho, Sung Ki

    2015-01-01

    Migration of stents is one of the most common adverse events in covered stent placement in GI tract obstruction. To compare physical property and migration rates in a canine colon obstruction model among a novel stent and conventional stents. Comparative physical test and animal study. Medical device testing laboratory and animal laboratory. Mongrel dogs (N=26). Surgical colon obstruction followed by placement of a novel (n=13) or conventional (n=13) stent. Physical properties, migration, and adverse events. The novel stent showed better flexibility, as in a physical test of longitudinal compressibility and axial force, than did conventional stents, and it withstood the fatigue test for 10 days. In terms of radial force and tensile strength, the novel stent showed the same or better results than conventional stents. In a canine colon obstruction model, the migration rate of a novel stent was significantly lower than that of a conventional stent (2/13, 15.4% vs 8/13, 61.5%; P=.008). Animal study of limited size. The novel, ring-connected stent is more flexible and more resistant to migration than the conventional stents. Copyright © 2015 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

  6. Clinical presentation and outcomes of coronary in-stent restenosis across 3-stent generations.

    Science.gov (United States)

    Magalhaes, Marco A; Minha, Sa'ar; Chen, Fang; Torguson, Rebecca; Omar, Al Fazir; Loh, Joshua P; Escarcega, Ricardo O; Lipinski, Michael J; Baker, Nevin C; Kitabata, Hironori; Ota, Hideaki; Suddath, William O; Satler, Lowell F; Pichard, Augusto D; Waksman, Ron

    2014-12-01

    Clinical presentation of bare metal stent in-stent restenosis (ISR) in patients undergoing target lesion revascularization is well characterized and negatively affects on outcomes, whereas the presentation and outcomes of first- and second-generation drug-eluting stents (DESs) remains under-reported. The study included 909 patients (1077 ISR lesions) distributed as follows: bare metal stent (n=388), first-generation DES (n=425), and second-generation DES (n=96), categorized into acute coronary syndrome (ACS) or non-ACS presentation mode at the time of first target lesion revascularization. ACS was further classified as myocardial infarction (MI) and unstable angina. For bare metal stent, first-generation DES and second-generation DES, ACS was the clinical presentation in 67.8%, 71.0%, and 66.7% of patients, respectively (P=0.470), whereas MI occurred in 10.6%, 10.1%, and 5.2% of patients, respectively (P=0.273). The correlates for MI as ISR presentation were current smokers (odds ratio, 3.02; 95% confidence interval [CI], 1.78-5.13; Ppresentations had an independent effect on major adverse cardiac events (death, MI, and re-target lesion revascularization) at 6 months (MI versus non-ACS: adjusted hazard ratio, 4.06; 95% CI, 1.84-8.94; Pclinical presentation is similar irrespective of stent type. MI as ISR presentation seems to be associated with patient and not device-related factors. ACS as ISR presentation has an independent effect on major adverse cardiac events, suggesting that ISR remains a hazard and should be minimized. © 2014 American Heart Association, Inc.

  7. Functional Self-Expandable Metal Stents in Biliary Obstruction

    Science.gov (United States)

    Kwon, Chang-Il; Ko, Kwang Hyun; Hahm, Ki Baik

    2013-01-01

    Biliary stents are widely used not only for palliative treatment of malignant biliary obstruction but also for benign biliary diseases. Each plastic stent or self-expandable metal stent (SEMS) has its own advantages, and a proper stent should be selected carefully for individual condition. To compensate and overcome several drawbacks of SEMS, functional self-expandable metal stent (FSEMS) has been developed with much progress so far. This article looks into the outcomes and defects of each stent type for benign biliary stricture and describes newly introduced FSEMSs according to their functional categories. PMID:24143314

  8. Effects of cobalt-chromium everolimus eluting stents or bare metal stent on fatal and non-fatal cardiovascular events

    DEFF Research Database (Denmark)

    Valgimigli, Marco; Sabaté, Manel; Kaiser, Christoph

    2014-01-01

    eluting stents with bare metal stents were selected. The principal investigators whose trials met the inclusion criteria provided data for individual patients. PRIMARY OUTCOMES: The primary outcome was cardiac mortality. Secondary endpoints were myocardial infarction, definite stent thrombosis, definite...... a significant reduction of cardiac mortality (hazard ratio 0.67, 95% confidence interval 0.49 to 0.91; P=0.01), myocardial infarction (0.71, 0.55 to 0.92; P=0.01), definite stent thrombosis (0.41, 0.22 to 0.76; P=0.005), definite or probable stent thrombosis (0.48, 0.31 to 0.73; P... coronary syndrome v stable coronary artery disease), diabetes mellitus, female sex, use of glycoprotein IIb/IIIa inhibitors, and up to one year v longer duration treatment with dual antiplatelets. CONCLUSIONS: This meta-analysis offers evidence that compared with bare metal stents the use of cobalt...

  9. Y-configuration double-stent-assisted coiling using two closed-cell stents for wide-neck basilar tip aneurysms.

    Science.gov (United States)

    Jeon, Pyoung; Kim, Byung Moon; Kim, Dong Joon; Kim, Dong I K; Park, Keun Young

    2014-09-01

    This study aimed to evaluate clinical and angiographic outcomes of Y-configuration double-stent-assisted (Y-stent) coiling using two closed-cell stents for wide-necked basilar tip aneurysm (BTA). A total of 25 patients underwent Y-stent coiling using two closed-cell stents as a first-time treatment in 18 (3 ruptured) BTAs, retreatment in 2 BTAs and as a third treatment in 5 wide-necked BTAs. Clinical and angiographic outcomes were evaluated retrospectively. Treatment-related complications were three (12.0 %) thromboembolic infarctions due to two acute in-stent thromboses and one embolism. Twenty-two (88 %) patients had favorable outcomes (modified Rankin scale score [mRS], 0-2) during the follow-up period (mean, 30 months; range, 6-54 months). Two patients died: one from initial subarachnoid hemorrhage and the other from intracerebral hemorrhage due to underlying Moyamoya disease. Post-treatment angiograms showed complete occlusion in nine aneurysms, residual neck in 11 aneurysms and residual sac in five aneurysms. Follow-up angiograms were available at least once between 5 to 34 months (mean, 16 months) in 21 patients. Nineteen patients showed improved or stable states (complete occlusion, n = 17; residual neck, n = 2). Major recurrences occurred in two BTAs (9.5 %). Those two major recurrent aneurysms had been large-sized aneurysms at the initial coiling procedure. Both showed not only coil compaction but also progressive growth to giant-sized aneurysms and intra-aneurysmal thrombus formation at the Y-stent coiling as a third-time treatment. Y-stent coiling using two closed-cell stents is a safe and durable treatment option for wide-necked BTA, but may have limited efficacy for large/giant sized and thrombosed aneurysms.

  10. Management of JJ stent-related symptoms.

    Science.gov (United States)

    Papatsoris, Athanasios; Dellis, Athanasios; Daglas, George; Sanguedolce, Francesco

    2014-01-01

    Ureteric JJ stents are inserted in numerous pa- tients as a routine procedure. Nevertheless, the ideal JJ stent that does not cause any lower urinary tract symptoms has not been developed yet. Even special validated ques- tionnaires have been used for the assessment of JJ stent-related symtoms. For the management of such symtoms usually alpha-blockers are admin- istered. Also, studies have examined the efficacy and safety of anticholinergics and calcium channel blo- ckers. In this article we review the literature upon the management of JJ stent-related symptoms.

  11. 21 CFR 884.3900 - Vaginal stent.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Vaginal stent. 884.3900 Section 884.3900 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES... stent. (a) Identification. A vaginal stent is a device used to enlarge the vagina by stretching, or to...

  12. New expandable metallic stents: An experimental study in vessels of dogs

    International Nuclear Information System (INIS)

    Song, Ho Young; Lee, Jung Min; Chung, Jin Young; Chung, Gyung Ho; Kim, Bog Yi; Kuh, Ja Houng

    1992-01-01

    Three-types of expandable metallic stents were constructed to evaluate the differences between the stents: one, formed in a cylindrical zigzag pattern wth stainless steel wire (Gianturco stent), another, made by coating the Gianturco stent with silicone rubber (Silicone stent), the third, made by coating the Gianturco stent with 24 carat gold (Gold stent) for tissue acceptance. A total of 69 stents (each 23 stents of Gianturco, Silicone, and Gold stents) of 8-12 mm in diameter and 20 mm long were placed into normal abdominal aorta, inferior vena cava and lilac artery of nine adults dogs for 2 weeks to 11 months. It was more difficult to introduce Silicone stent into an introducing sheath than Gianturco or Gold stent due to the thickness of silicone rubber. Four Gianturco stents and three Silicone stents showed migration but Gold stent did not. Luminal narrowing or occlusion was noted in 3 Silicone stents. In 2 Gianturco stents, and in 1 Gold stent. Neointimal proliferation over the stent wires was more rapid and even in Gold stent than Silicone or Gianturco stent. Although further study is needed, Gold stent seems to be better than Gianturco or Silicone stent as an endovascular graft material

  13. New expandable metallic stents: An experimental study in vessels of dogs

    Energy Technology Data Exchange (ETDEWEB)

    Song, Ho Young; Lee, Jung Min; Chung, Jin Young; Chung, Gyung Ho; Kim, Bog Yi; Kuh, Ja Houng [Chunbuk National University Medical School, Chunju (Korea, Republic of)

    1992-07-15

    Three-types of expandable metallic stents were constructed to evaluate the differences between the stents: one, formed in a cylindrical zigzag pattern wth stainless steel wire (Gianturco stent), another, made by coating the Gianturco stent with silicone rubber (Silicone stent), the third, made by coating the Gianturco stent with 24 carat gold (Gold stent) for tissue acceptance. A total of 69 stents (each 23 stents of Gianturco, Silicone, and Gold stents) of 8-12 mm in diameter and 20 mm long were placed into normal abdominal aorta, inferior vena cava and lilac artery of nine adults dogs for 2 weeks to 11 months. It was more difficult to introduce Silicone stent into an introducing sheath than Gianturco or Gold stent due to the thickness of silicone rubber. Four Gianturco stents and three Silicone stents showed migration but Gold stent did not. Luminal narrowing or occlusion was noted in 3 Silicone stents. In 2 Gianturco stents, and in 1 Gold stent. Neointimal proliferation over the stent wires was more rapid and even in Gold stent than Silicone or Gianturco stent. Although further study is needed, Gold stent seems to be better than Gianturco or Silicone stent as an endovascular graft material.

  14. Interval biliary stent placement via percutaneous ultrasound guided cholecystostomy: another approach to palliative treatment in malignant biliary tract obstruction.

    Science.gov (United States)

    Harding, James; Mortimer, Alex; Kelly, Michael; Loveday, Eric

    2010-12-01

    Percutaneous cholecystostomy is a minimally invasive procedure for providing gallbladder decompression, often in critically ill patients. It can be used in malignant biliary obstruction following failed endoscopic retrograde cholangiopancreatography when the intrahepatic ducts are not dilated or when stent insertion is not possible via the bile ducts. In properly selected patients, percutaneous cholecystostomy in obstructive jaundice is a simple, safe, and rapid option for biliary decompression, thus avoiding the morbidity and mortality involved with percutaneous transhepatic biliary stenting. Subsequent use of a percutaneous cholecystostomy for definitive biliary stent placement is an attractive concept and leaves patients with no external drain. To the best of our knowledge, it has only been described on three previous occasions in the published literature, on each occasion forced by surgical or technical considerations. Traditionally, anatomic/technical considerations and the risk of bile leak have precluded such an approach, but improvements in catheter design and manufacture may now make it more feasible. We report a case of successful interval metal stent placement via percutaneous cholecystostomy which was preplanned and achieved excellent palliation for the patient. The pros and cons of the procedure and approach are discussed.

  15. Interval Biliary Stent Placement Via Percutaneous Ultrasound Guided Cholecystostomy: Another Approach to Palliative Treatment in Malignant Biliary Tract Obstruction

    International Nuclear Information System (INIS)

    Harding, James; Mortimer, Alex; Kelly, Michael; Loveday, Eric

    2010-01-01

    Percutaneous cholecystostomy is a minimally invasive procedure for providing gallbladder decompression, often in critically ill patients. It can be used in malignant biliary obstruction following failed endoscopic retrograde cholangiopancreatography when the intrahepatic ducts are not dilated or when stent insertion is not possible via the bile ducts. In properly selected patients, percutaneous cholecystostomy in obstructive jaundice is a simple, safe, and rapid option for biliary decompression, thus avoiding the morbidity and mortality involved with percutaneous transhepatic biliary stenting. Subsequent use of a percutaneous cholecystostomy for definitive biliary stent placement is an attractive concept and leaves patients with no external drain. To the best of our knowledge, it has only been described on three previous occasions in the published literature, on each occasion forced by surgical or technical considerations. Traditionally, anatomic/technical considerations and the risk of bile leak have precluded such an approach, but improvements in catheter design and manufacture may now make it more feasible. We report a case of successful interval metal stent placement via percutaneous cholecystostomy which was preplanned and achieved excellent palliation for the patient. The pros and cons of the procedure and approach are discussed.

  16. Iliocaval Confluence Stenting for Chronic Venous Obstructions

    Energy Technology Data Exchange (ETDEWEB)

    Graaf, Rick de, E-mail: r.de.graaf@mumc.nl [Maastricht University Medical Centre (MUMC), Department of Radiology (Netherlands); Wolf, Mark de, E-mail: markthewolf@gmail.com [Maastricht University Medical Centre (MUMC), Department of Surgery (Netherlands); Sailer, Anna M., E-mail: anni.sailer@mumc.nl [Maastricht University Medical Centre (MUMC), Department of Radiology (Netherlands); Laanen, Jorinde van, E-mail: jorinde.van.laanen@mumc.nl; Wittens, Cees, E-mail: c.wittens@me.com [Maastricht University Medical Centre (MUMC), Department of Surgery (Netherlands); Jalaie, Houman, E-mail: hjalaie@ukaachen.de [University Hospital Aachen, Department of Surgery (Germany)

    2015-10-15

    PurposeDifferent techniques have been described for stenting of venous obstructions. We report our experience with two different confluence stenting techniques to treat chronic bi-iliocaval obstructions.Materials and MethodsBetween 11/2009 and 08/2014 we treated 40 patients for chronic total bi-iliocaval obstructions. Pre-operative magnetic resonance venography showed bilateral extensive post-thrombotic scarring in common and external iliac veins as well as obstruction of the inferior vena cava (IVC). Stenting of the IVC was performed with large self-expandable stents down to the level of the iliocaval confluence. To bridge the confluence, either self-expandable stents were placed inside the IVC stent (24 patients, SECS group) or high radial force balloon-expandable stents were placed at the same level (16 patients, BECS group). In both cases, bilateral iliac extensions were performed using nitinol stents.ResultsRecanalization was achieved for all patients. In 15 (38 %) patients, a hybrid procedure with endophlebectomy and arteriovenous fistula creation needed to be performed because of significant involvement of inflow vessels below the inguinal ligament. Mean follow-up was 443 ± 438 days (range 7–1683 days). For all patients, primary, assisted-primary, and secondary patency rate at 36 months were 70, 73, and 78 %, respectively. Twelve-month patency rates in the SECS group were 85, 85, and 95 % for primary, assisted-primary, and secondary patency. In the BECS group, primary patency was 100 % during a mean follow-up period of 134 ± 118 (range 29–337) days.ConclusionStenting of chronic bi-iliocaval obstruction shows relatively high patency rates at medium follow-up. Short-term patency seems to favor confluence stenting with balloon-expandable stents.

  17. Complication after self expandable metallic stent for esophageal cancer

    International Nuclear Information System (INIS)

    Nagahama, Takeshi; Maruyama, Michio; Kato, Kiyomi; Shinoura, Hiroshi; Hasegawa, Kumi; Takashima, Itaru; Ebuchi, Masakazu

    2003-01-01

    Major complications after placement of esophageal stent and airway stent were reviewed and evaluated. Four patients, including two patients with perforations and two patients with fistula formation, developed major complications after placement of a self expandable metallic stent. Two patients underwent additional radiation to improve stricture after stent placement. In one patient, stent placement was selected to improve esophageal stricture that occurred after radical radiation therapy. In one patient, migration of stent into the lesion caused a perforation. It can be concluded that additional radiation after stent placement increases the risk of complication. Stent migration also can lead to the risk of perforation. (author)

  18. The Role Of Inflammation In Stent Restenosis More Than 1 Year Afetr Drug Eluting Stent Implantation

    Directory of Open Access Journals (Sweden)

    Hasan Shemirani

    2011-09-01

    Full Text Available Background: In stent restenosis (ISR following endovascular interventions is the main limitation of their long-term success. Despite advances have been made during recent years to decrease restenosis, it remains a challenging clinical problem.The aim of this study was to evaluate the relationship between angiographic coronary in stent restenosis, inflammation after successful stent implantation. Methods: This study included 78 patients, 35year old and higher who underwent coronary angiography more than 1 year after drug-eluting stent (DES implantation because of symptoms suggestive ischemia. Patients were divided into ISR group (case and patent stent group (control according to angiography results. For all patients blood lipids and high sensitivity C-Reactive Protein (hsCRP were measured simultaneously. Results: Age, sex, hypertension, current smoking, and lipid profile other than High Density Lipoprotein (HDL-C of patients in the case and control groups were similar .However, HDL-C < 40mg/L was more prevalent with ISR (66.7% vs. 30.8%, p=0.002. The hsCRP level was 2.98±2.06 mg/L in the case group and 2.50±1.80 mg/L in the control group. There were no significant differences in mean hsCRP concentration between the two groups (p=0.14, however mean hsCRP level was significantly higher in men of case group than control group (3.35mg/L vs. 2.21mg/L, p<0.05. Conclusion: This study demonstrates that in men but not in women inflammation may be a predictor of in stent restenosis more than 1 year after drug eluting stent implantation. Also, high-density lipoprotein (HDL probably has protective effect against stent restenosis.

  19. Effects of cobalt-chromium everolimus eluting stents or bare metal stent on fatal and non-fatal cardiovascular events: patient level meta-analysis.

    Science.gov (United States)

    Valgimigli, Marco; Sabaté, Manel; Kaiser, Christoph; Brugaletta, Salvatore; de la Torre Hernandez, Jose Maria; Galatius, Soeren; Cequier, Angel; Eberli, Franz; de Belder, Adam; Serruys, Patrick W; Ferrante, Giuseppe

    2014-11-04

    To examine the safety and effectiveness of cobalt-chromium everolimus eluting stents compared with bare metal stents. Individual patient data meta-analysis of randomised controlled trials. Cox proportional regression models stratified by trial, containing random effects, were used to assess the impact of stent type on outcomes. Hazard ratios with 95% confidence interval for outcomes were reported. Medline, Embase, the Cochrane Central Register of Controlled Trials. Randomised controlled trials that compared cobalt-chromium everolimus eluting stents with bare metal stents were selected. The principal investigators whose trials met the inclusion criteria provided data for individual patients. The primary outcome was cardiac mortality. Secondary endpoints were myocardial infarction, definite stent thrombosis, definite or probable stent thrombosis, target vessel revascularisation, and all cause death. The search yielded five randomised controlled trials, comprising 4896 participants. Compared with patients receiving bare metal stents, participants receiving cobalt-chromium everolimus eluting stents had a significant reduction of cardiac mortality (hazard ratio 0.67, 95% confidence interval 0.49 to 0.91; P=0.01), myocardial infarction (0.71, 0.55 to 0.92; P=0.01), definite stent thrombosis (0.41, 0.22 to 0.76; P=0.005), definite or probable stent thrombosis (0.48, 0.31 to 0.73; Pstents the use of cobalt-chromium everolimus eluting stents improves global cardiovascular outcomes including cardiac survival, myocardial infarction, and overall stent thrombosis. © Valgimigli et al 2014.

  20. Metallic ureteral stents in malignant ureteral obstruction: short-term results and radiological features predicting stent failure in patients with non-urological malignancies.

    Science.gov (United States)

    Chow, Po-Ming; Hsu, Jui-Shan; Wang, Shuo-Meng; Yu, Hong-Jheng; Pu, Yeong-Shiau; Liu, Kao-Lang

    2014-06-01

    To provide short-term result of the metallic ureteral stent in patients with malignant ureteral obstruction and identify radiological findings predicting stent failure. The records of all patients with non-urological malignant diseases who have received metallic ureteral stents from July 2009 to March 2012 for ureteral obstruction were reviewed. Stent failure was detected by clinical symptoms and imaging studies. Survival analysis was used to estimate patency rates and factors predicting stent failure. A total of 74 patients with 130 attempts of stent insertion were included. A total of 113 (86.9 %) stents were inserted successfully and 103 (91.2 %) achieved primary patency. After excluding cases without sufficient imaging data, 94 stents were included in the survival analysis. The median functional duration of the 94 stents was 6.2 months (range 3-476 days). Obstruction in abdominal ureter (p = 0.0279) and lymphatic metastasis around ureter (p = 0.0398) were risk factors for stent failure. The median functional durations of the stents for abdominal and pelvic obstructions were 4.5 months (range 3-263 days) and 6.5 months (range 4-476 days), respectively. The median durations of the stents with and without lymphatic metastasis were 5.3 months (range 4-398 days) and 7.8 months (range 31-476 days), respectively. Metallic ureteral stents are effective and safe in relieving ureteral obstructions resulting from non-urological malignancies, and abdominal ureteral obstruction and lymphatic metastasis around ureter were associated with shorter functional duration.

  1. A sirolimus-eluting bioabsorbable polymer-coated stent (MiStent) versus an everolimus-eluting durable polymer stent (Xience) after percutaneous coronary intervention (DESSOLVE III): a randomised, single-blind, multicentre, non-inferiority, phase 3 trial.

    Science.gov (United States)

    de Winter, Robbert J; Katagiri, Yuki; Asano, Taku; Milewski, Krzysztof P; Lurz, Philipp; Buszman, Pawel; Jessurun, Gillian A J; Koch, Karel T; Troquay, Roland P T; Hamer, Bas J B; Ophuis, Ton Oude; Wöhrle, Jochen; Wyderka, Rafał; Cayla, Guillaume; Hofma, Sjoerd H; Levesque, Sébastien; Żurakowski, Aleksander; Fischer, Dieter; Kośmider, Maciej; Goube, Pascal; Arkenbout, E Karin; Noutsias, Michel; Ferrari, Markus W; Onuma, Yoshinobu; Wijns, William; Serruys, Patrick W

    2018-02-03

    MiStent is a drug-eluting stent with a fully absorbable polymer coating containing and embedding a microcrystalline form of sirolimus into the vessel wall. It was developed to overcome the limitation of current durable polymer drug-eluting stents eluting amorphous sirolimus. The clinical effect of MiStent sirolimus-eluting stent compared with a durable polymer drug-eluting stents has not been investigated in a large randomised trial in an all-comer population. We did a randomised, single-blind, multicentre, phase 3 study (DESSOLVE III) at 20 hospitals in Germany, France, Netherlands, and Poland. Eligible participants were any patients aged at least 18 years who underwent percutaneous coronary intervention in a lesion and had a reference vessel diameter of 2·50-3·75 mm. We randomly assigned patients (1:1) to implantation of either a sirolimus-eluting bioresorbable polymer stent (MiStent) or an everolimus-eluting durable polymer stent (Xience). Randomisation was done by local investigators via web-based software with random blocks according to centre. The primary endpoint was a non-inferiority comparison of a device-oriented composite endpoint (DOCE)-cardiac death, target-vessel myocardial infarction, or clinically indicated target lesion revascularisation-between the groups at 12 months after the procedure assessed by intention-to-treat. A margin of 4·0% was defined for non-inferiority of the MiStent group compared with the Xience group. All participants were included in the safety analyses. This trial is registered with ClinicalTrials.gov, number NCT02385279. Between March 20, and Dec 3, 2015, we randomly assigned 1398 patients with 2030 lesions; 703 patients with 1037 lesions were assigned to MiStent, of whom 697 received the index procedure, and 695 patients with 993 lesions were asssigned to Xience, of whom 690 received the index procedure. At 12 months, the primary endpoint had occurred in 40 patients (5·8%) in the sirolimus-eluting stent group and in 45

  2. Assessment Of Coronary Arterial Stents By Multislice-CT Angiography

    International Nuclear Information System (INIS)

    Maintz, D.; Fallenberg, E. M.; Heindel, W.; Fischbach, R.; Grude, M.

    2003-01-01

    Purpose: To assess patency and lumen visibility of coronary artery stents by multislice-CT angiography (MSCTA) in comparison with conventional coronary angiography as the standard of reference. Material and Methods: 47 stents of 13 different types were evaluated in 29 patients. MSCTA was performed on a 4-slice scanner with a standard coronary protocol (detector collimation 4 x 1 mm; table feed 1.5 mm/rotation, 400 mAs, 120 kV). Image evaluation was performed by two readers who were blinded to the reports from the catheter angiography. MIP reconstructions were evaluated for image quality on a 4-point scale (1 = poor, 4 = excellent) and stent patency (contrast distal to the stent as an indirect patency sign). Axial images and multiplanar reformations through the stents were used for assessment of stent lumen visibility (measurement of the visible stent lumen diameter) and detection of relevant in-stent stenosis (50%). Results: Image quality was fair to good on average (score 2.64 ± 1.0) and depended on the heart rate (heart rate 45-60: average score 3.2, heart rate 61-70: average score 2.8, heart rate >71: average score 1.4). Thirty-seven stents were correctly classified as patent, 1 was correctly classified as occluded and 9 stents were not assessable due to insufficient image quality because of triggering artifacts. Parts of the stent lumen could be visualized in 30 cases. On average, 20-40% of the stent lumen diameter was visible. Twenty-five stents were correctly classified as having no stenosis, 1 was falsely classified as stenosed, 1 was correctly classified as occluded. In 20 stents lumen visibility was not sufficient for stenosis evaluation. Conclusion: Although the stent lumen may be partly visualized in most stents, a reliable evaluation of in-stent stenoses does not seem practical by 4-slice MSCT. Nevertheless, for stent patency evaluation, MS-CTA might provide valuable clinical information. With submillimeter MSCT (e.g. 16-slice scanners) and more

  3. Risk factors for proximal migration of biliary tube stents.

    Science.gov (United States)

    Kawaguchi, Yoshiaki; Ogawa, Masami; Kawashima, Yohei; Mizukami, Hajime; Maruno, Atsuko; Ito, Hiroyuki; Mine, Tetsuya

    2014-02-07

    To analyze the risk factors for biliary stent migration in patients with benign and malignant strictures. Endoscopic stent placement was performed in 396 patients with bile duct stenosis, at our institution, between June 2003 and March 2009. The indications for bile duct stent implantation included common bile duct stone in 190 patients, malignant lesions in 112, chronic pancreatitis in 62, autoimmune pancreatitis in 14, trauma in eight, surgical complications in six, and primary sclerosing cholangitis (PSC) in four. We retrospectively examined the frequency of stent migration, and analyzed the patient factors (disease, whether endoscopic sphincterotomy was performed, location of bile duct stenosis and diameter of the bile duct) and stent characteristics (duration of stent placement, stent type, diameter and length). Moreover, we investigated retrieval methods for migrated stents and their associated success rates. The frequency of tube stent migration in the total patient population was 3.5%. The cases in which tube stent migration occurred included those with common bile duct stones (3/190; 1.6%), malignant lesions (2/112; 1.8%), chronic pancreatitis (4/62; 6.5%), autoimmune pancreatitis (2/14; 14.3%), trauma (1/8; 12.5%), surgical complications (2/6; 33.3%), and PSC (0/4; 0%). The potential risk factors for migration included bile duct stenosis secondary to benign disease such as chronic pancreatitis and autoimmune pancreatitis (P = 0.030); stenosis of the lower bile duct (P = 0.031); bile duct diameter > 10 mm (P = 0.023); duration of stent placement > 1 mo (P = 0.007); use of straight-type stents (P stents (P stents was successful in all cases. The grasping technique, using a basket or snare, was effective for pig-tailed or thin and straight stents, whereas the guidewire cannulation technique was effective for thick and straight stents. Migration of tube stents within the bile duct is rare but possible, and it is important to determine the risk factors

  4. Stenting plus coiling: dangerous or helpful?; Stenting plus Coiling bei akut rupturierten intrakraniellen Aneurysmen

    Energy Technology Data Exchange (ETDEWEB)

    Wanke, I.; Gizewski, E.; Doerfler, A.; Stolke, D.; Forsting, M. [Essen Univ. (Germany). Inst. fuer Radiologie und Neuroradiologie

    2005-09-01

    Purpose: the purpose of this study was to evaluate the procedural risk of treating acute ruptured aneurysms with a stentcoil combination. Material and methods: between August 2001 and January 2004 we treated nine acute subarachnoid hemorrhage (SAH) patients with a combination of stents and platinum coils. Results: six aneurysms were 100% eliminated; the residual three aneurysms had a 95% to 99% occlusion. A transient thrombosis in the stent in one patient could be recanalized by intravenous application of ReoPro {sup registered}. In another patient an occlusive vasospasm at the distal end of the stent was successfully treated with intraarterial Nimotop {sup registered}. Neurological complications occurred in none of the patients. Conclusion: in broad-based aneurysms which cannot be clipped or in which any neurosurgical treatment presents an unacceptably high risk (posterior circulation and paraophthalmic aneurysms), treatment using a combination of stent and platinum coils might be an option even in the acute phase of an SAH. Platelet aggregation can be treated with Aspirin registered and Plavix {sup registered} after placement of the first coil, vasospasms with intraarterial Nimotop {sup registered}, and acute stent thrombosis with GP IIa/IIIb-antagonists. (orig.)

  5. TACE Combined with Implantation of Irradiation Stent Versus TACE Combine with Bare Stent for HCC Complicated by IVCTT

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Qing-hui; Zhang, Wen; Liu, Qing-xin; Liu, Ling-xiao [Fudan University, Department of Interventional Radiology, Zhongshan Hospital (China); Wu, Lin-lin [Tengzhou Central People’s Hospital, Department of Oncology (China); Wang, Jian-hua; Yan, Zhi-ping, E-mail: 798373254@qq.com; Luo, Jian-jun, E-mail: 12211210022@fudan.edu.cn [Fudan University, Department of Interventional Radiology, Zhongshan Hospital (China)

    2016-09-15

    PurposeThis study was designed to evaluate the safety and efficacy of transarterial chemoembolization (TACE) combined with intra-IVC implantation of an irradiation stent for the treatment of hepatocellular carcinoma (HCC) complicated by inferior vena cava tumor thrombosis (IVCTT).MethodsSixty-one consecutive patients with HCC complicated by IVCTT treated by TACE combined with IVC stenting were retrospectively analysed. IVC stenting was performed using a stent loaded with {sup 125}I seeds strands (the irradiation stent) in 33 patients (Group A) and 28 patients with a bare stent (Group B). Propensity score matching eliminated the baseline differences. Overall survival, oedema related to IVC obstruction remission rate and procedure-related adverse events were compared between the two groups.ResultsThe adverse effect rate was similar for both Group A and Group B patients, and complications were adequately handled by medical treatment. TACE combined with implantation of an irradiation stent showed a significant median survival benefit over TACE combined with a bare stent, with a median survival time of 203.0 ± 28.135 days versus 93.0 ± 24.341 days (p = 0.006). The propensity score-matched (24 pairs) cohort analyses (200 ± 31.231 days vs. 66 ± 23.270 days, p = 0.019). The oedema remission rate was 97.0 % in group A patients and 96.4 % in group B, respectively. TACE-irradiation stent and object tumor response were the independent prognostic factors of favorable survival.ConclusionsTACE combined with irradiation stent implantation is a safe and effective treatment modality for patients with HCC complicated by IVCTT and may extend their survival time.

  6. Zotarolimus-eluting stent for the treatment of recurrent, severe carotid artery in-stent stenosis in the TARGET-CAS population.

    Science.gov (United States)

    Tekieli, Lukasz; Pieniazek, Piotr; Musialek, Piotr; Kablak-Ziembicka, Anna; Przewlocki, Tadeusz; Trystula, Mariusz; Moczulski, Zbigniew; Dzierwa, Karolina; Paluszek, Piotr; Podolec, Piotr

    2012-06-01

    To evaluate the safety and efficacy of a balloon-mounted drug-eluting stent (DES) for recurrent carotid in-stent stenosis (ISS). As part of our targeted carotid artery stenting (TARGET-CAS) protocol, neurological and ultrasound evaluations have been performed at 3, 6, and 12 months and then annually since 2001 in all carotid stent patients. For angiographically-confirmed >70% ISS, balloon angioplasty was performed as a first-line treatment. Recurrent ISS was treated with a 4.0-mm zotarolimus-eluting coronary stent (ZES) that was postdilated according to intravascular ultrasound imaging. Among the 1350 neuroprotected CAS procedures performed between January 2001 and March 2011, there were 7 (0.52%) patients (5 men; ages 51-72 years), all neurologically asymptomatic, with >70% recurrent ISS that occurred at 5 to 11 months after the initial balloon angioplasty treatment for ISS. ZES implantation under distal embolic protection was technically successful and uncomplicated. Angiographic stenosis was reduced from 84.6%±7.5% to 10.7%±3.6% (p<0.01). In 5 patients with ZES implanted fully within the self-expanding carotid stent, duplex ultrasound follow-up (mean 17 months, range 6-36) revealed no evidence of restenosis or stent fracture/deformation. In the 2 other patients, the ZES had been implanted for distal edge ISS such that the ZES protruded beyond the original carotid stent. This protruding segment of the ZES demonstrated deformation/kinking in both; in one, this led to symptomatic stent occlusion. The use of coronary ZES in the treatment of recurrent carotid ISS is feasible and appears effective provided the ZES is placed entirely within the original stent. Placement of a coronary ZES outside the carotid stent scaffold should be avoided.

  7. Randomized multicenter study of multiple plastic stents vs. covered self-expandable metallic stent in the treatment of biliary stricture in chronic pancreatitis.

    Science.gov (United States)

    Haapamäki, Carola; Kylänpää, Leena; Udd, Marianne; Lindström, Outi; Grönroos, Juha; Saarela, Arto; Mustonen, Harri; Halttunen, Jorma

    2015-07-01

    The use of covered self-expandable metallic stents (cSEMS) in benign biliary indications is evolving. The aim of the study was to assess the safety and feasibility of cSEMS compared with multiple plastic stents in the treatment of benign biliary stricture (BBS) caused by chronic pancreatitis. This was a prospective, multicenter, randomized study of 60 patients with BBS caused by chronic pancreatitis. All patients received an initial plastic stent before randomization. At randomization, the stent was replaced either with a single cSEMS or three plastic stents. After 3 months, the position of the cSEMS was checked or another three plastic stents were added. At 6 months after randomization, all stents were removed. Clinical follow-up including abdominal ultrasound and laboratory tests were performed at 6 months and 2 years after stent removal. Two patients dropped out of the cSEMS group before stent removal. In April 2014, the median follow-up was 40 months (range 1 - 66 months). The 2-year, stricture-free success rate was 90 % (95 % confidence interval [CI] 72 % - 97 %) in the plastic stent group and 92 % (95 %CI 70 % - 98 %) in the cSEMS group (P = 0.405). There was one late recurrence in the plastic stent group 50 months after stent removal. Stent migration occurred three times (10 %) in the plastic stent group and twice in the cSEMS group (7 %; P = 1.000). A 6-month treatment with either six 10-Fr plastic stents or with one 10-mm cSEMS produced good long-term relief of biliary stricture caused by chronic pancreatitis.Study registered at ClinicalTrials.gov (NCT01085747). © Georg Thieme Verlag KG Stuttgart · New York.

  8. Percutaneous Ureteral stent insertion

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Yup; Sung, Dong Wook; Choi, Woo Suk; Lee, Dong Ho; Ko, Young Tae; Lee, Sun Wha; Lim, Jae Hoon [Kyung Hee University Hospital, Seoul (Korea, Republic of)

    1990-10-15

    Percutaneous ureteral stent insertion is a treatment of permanent or temporary urinary diversion to maintain continuity and function of the obstructed and injured ureter. We performed 31 cases of percutaneous double pig tall ureteral stent insertion in 21 patients, included 13 patients with malignant ureteral obstruction and eight patients with injured ureter as well as benign inflammatory stricture. Satisfactory resulted was obtained in all patients but one, who need percutaneous nephrostomy on week later for urinary diversion. No significant complication was encountered. The authors concluded that percutaneous ureteral stent insertion, an interventional procedure alternative to urologic retrograde method, is an effective method for urinary diversion.

  9. Mechanisms of Biliary Plastic Stent Occlusion and Efforts at Prevention

    Directory of Open Access Journals (Sweden)

    Chang-Il Kwon

    2016-03-01

    Full Text Available Biliary stenting via endoscopic retrograde cholangiopancreatography has greatly improved the quality of patient care over the last 30 years. Plastic stent occlusion limits the life span of such stents. Attempts to improve plastic stent patency duration have mostly failed. Metal stents (self-expandable metal stents [SEMSs] have therefore replaced plastic stents, especially for malignant biliary strictures. SEMS are at least 10 times more expensive than plastic stents. In this focused review, we will discuss basic mechanisms of plastic stent occlusion, along with a systematic summary of previous efforts and related studies to improve stent patency and potential new techniques to overcome existing limitations.

  10. An ovine in vivo framework for tracheobronchial stent analysis.

    Science.gov (United States)

    McGrath, Donnacha J; Thiebes, Anja Lena; Cornelissen, Christian G; O'Shea, Mary B; O'Brien, Barry; Jockenhoevel, Stefan; Bruzzi, Mark; McHugh, Peter E

    2017-10-01

    Tracheobronchial stents are most commonly used to restore patency to airways stenosed by tumour growth. Currently all tracheobronchial stents are associated with complications such as stent migration, granulation tissue formation, mucous plugging and stent strut fracture. The present work develops a computational framework to evaluate tracheobronchial stent designs in vivo. Pressurised computed tomography is used to create a biomechanical lung model which takes into account the in vivo stress state, global lung deformation and local loading from pressure variation. Stent interaction with the airway is then evaluated for a number of loading conditions including normal breathing, coughing and ventilation. Results of the analysis indicate that three of the major complications associated with tracheobronchial stents can potentially be analysed with this framework, which can be readily applied to the human case. Airway deformation caused by lung motion is shown to have a significant effect on stent mechanical performance, including implications for stent migration, granulation formation and stent fracture.

  11. Are bio-absorbable stents the future of SFA treatment?

    Science.gov (United States)

    Peeters, P; Keirse, K; Verbist, J; Deloose, K; Bosiers, M

    2010-02-01

    Several limitations inherent to the implantation of a metallic device, such as the occurrence of in-stent re-stenosis, in an arterial lumen intuitively explain the interest for developing bio-absorbable stents. Two main types of bio-absorbable stents currently exist: polymer stents and metallic stents. To date, no studies with bio-absorbable stents have been conducted in the superficial femoral artery (SFA). Because of their strut thickness and lack of radial force, polymer stents are no good candidates for endovascular use. Absorbable metal stents (AMS) do have the potential to perform well for artery treatment, although current evidence from in-human coronary and infrapopliteal studies yield unsatisfactory results. Drastic technological improvements are mandatory before AMS can be considered for every day practice. Yet, it is our belief that further development of other metal and non-metal bio-absorbable stents, with or without drug-coating, may lead to the creation of the ultimate SFA stent.

  12. Duplex criteria for determination of in-stent stenosis after angioplasty and stenting of the superficial femoral artery.

    Science.gov (United States)

    Baril, Donald T; Rhee, Robert Y; Kim, Justine; Makaroun, Michel S; Chaer, Rabih A; Marone, Luke K

    2009-01-01

    Endovascular intervention is considered first-line therapy for most superficial femoral artery (SFA) occlusive disease. Duplex ultrasound (DU) criteria for SFA in-stent stenosis and correlation with angiographic data remain poorly defined. This study evaluated SFA-specific DU criteria for the assessment of SFA in-stent stenosis. From May 2003 to May 2008, 330 limbs underwent SFA angioplasty and stenting and were monitored by serial DU imaging. Suspected stenotic lesions underwent angiography and intervention when appropriate. Data pairs of DU and angiographically estimated stenosis or=50% in-stent stenosis, a PSV >or=190 had 88% sensitivity, 95% specificity, a 98% positive predictive value (PPV), and a 72% negative predictive value (NPV); for Vr, a ratio of >1.50 had 93% sensitivity, 89% specificity, a 96% PPV, and a 81% NPV. To detect >or=80% in-stent stenosis, a PSV >or=275 had 97% sensitivity, 68% specificity, a 67% PPV, and a 97% NPV; a Vr ratio >or=3.50 had 74% sensitivity, 94% specificity, a 77% PPV, and a 88% NPV. Combining a PSV >or=275 and a Vr >or=3.50 to determine >or=80% in-stent stenosis had 74% sensitivity, 94% specificity, a 88% PPV, and a 85% NPV; odds ratio was 42.17 (95% confidence interval, 10.20-174.36, P or=80% in-stent stenosis. A significant drop in ABI (>0.15) correlated with a >62% in-stent stenosis, although the adjusted correlation coefficients was low (R(2) = 0.31, P = .02). PSV and Vr appear to have a significant role in predicting in-stent stenosis. To determine >or=80% stenosis, combining PSV >or=275 cm/s and Vr >or=3.50 is highly specific and predictive.

  13. Delayed colonic perforation following stent placement for colorectal obstruction: a description of two cases with stent palliation.

    Directory of Open Access Journals (Sweden)

    Jalal Vahedian Ardakani

    2013-10-01

    Full Text Available Bowel stent insertion has a variety of complications one major of which is colonic perforation. The purpose of this article is to reveal two cases with delayed colonic perforation after stent placement to relieve bowel obstruction caused by rectal cancer. The first patient was a 55 year-old man who was a candidate for stent placement to avoid palliative surgery and relieve his bowel obstruction. Although the procedure resulted in complete relief of patient symptoms, but he returned with signs of peritonitis 10 days after the stent placement. A perforation was found at rectosigmoid junction on laparotomy. The second patient was a 60 year-old man who underwent a successful stent placement and returned 3 months later with a complaint of abdominal pain that showed up to be due to a rectal perforation on investigations. In conclusion, bowel perforation following stent placement can be a major complication, so close follow-up is necessary to detect it as soon as possible and prevent it from becoming an irreparable complication.

  14. Chest pain following oesophageal stenting for malignant dysphagia

    Energy Technology Data Exchange (ETDEWEB)

    Golder, Mark; Tekkis, Paris P.; Kennedy, Colette; Lath, Sadaf; Toye, Rosemary; Steger, Adrian C

    2001-03-01

    AIM: The palliative use of self-expanding metallic stents has been widely reported to relieve dysphagia in cases of oesophageal carcinoma. Little has been documented on the severity of chest pain following oesophageal stenting. The aim of this study was to investigate the association of pain with oesophageal stenting for malignant dysphagia. METHODS: Fifty-two patients with inoperable oesophageal carcinoma underwent stent placement between 1995-1999. Daily opioid analgesic requirements (mg of morphine equivalent doses) were monitored for 3 days before and 7 days after stenting. The degree of palliation was expressed as a dysphagia score (0-3). Hospital stay, readmission days, stent complications and patient survival time were also recorded. RESULTS: Twenty-six patients (50%) required opioid analgesia for chest pain (median dose: 80 mg morphine/day) within 48 h of the procedure compared to 11 (21.2%) patients before stenting (P = 0.0041). A significant increase was evident in the analgesic consumption following stent deployment (P < 0.001). The dysphagia score improved by a median value of 1 (CI 0.25)P < 0.001, with a re-intervention rate of 11.5%. The median survival time was 40 days post stenting (range 1-120). CONCLUSION: A significant proportion of patients developed chest pain after oesophageal stenting, requiring high dose opioid analgesia. As the origin of the pain is still unknown, pre-emptive analgesia may a play role in reducing stent-related morbidity and possibly in-hospital stay. Golder, M. et al. (2001)

  15. Chest pain following oesophageal stenting for malignant dysphagia

    International Nuclear Information System (INIS)

    Golder, Mark; Tekkis, Paris P.; Kennedy, Colette; Lath, Sadaf; Toye, Rosemary; Steger, Adrian C.

    2001-01-01

    AIM: The palliative use of self-expanding metallic stents has been widely reported to relieve dysphagia in cases of oesophageal carcinoma. Little has been documented on the severity of chest pain following oesophageal stenting. The aim of this study was to investigate the association of pain with oesophageal stenting for malignant dysphagia. METHODS: Fifty-two patients with inoperable oesophageal carcinoma underwent stent placement between 1995-1999. Daily opioid analgesic requirements (mg of morphine equivalent doses) were monitored for 3 days before and 7 days after stenting. The degree of palliation was expressed as a dysphagia score (0-3). Hospital stay, readmission days, stent complications and patient survival time were also recorded. RESULTS: Twenty-six patients (50%) required opioid analgesia for chest pain (median dose: 80 mg morphine/day) within 48 h of the procedure compared to 11 (21.2%) patients before stenting (P = 0.0041). A significant increase was evident in the analgesic consumption following stent deployment (P < 0.001). The dysphagia score improved by a median value of 1 (CI 0.25)P < 0.001, with a re-intervention rate of 11.5%. The median survival time was 40 days post stenting (range 1-120). CONCLUSION: A significant proportion of patients developed chest pain after oesophageal stenting, requiring high dose opioid analgesia. As the origin of the pain is still unknown, pre-emptive analgesia may a play role in reducing stent-related morbidity and possibly in-hospital stay. Golder, M. et al. (2001)

  16. Evolution of patency rates of self-expandable bare metal stents for endovascular treatment of femoro-popliteal arterial occlusive disease: Does stent design matter?

    Science.gov (United States)

    Treitl, Karla Maria; Woerner, Benedikt; Schinner, Regina; Czihal, Michael; Notohamiprodjo, Susan; Hoffmann, Ulrich; Treitl, Marcus

    2017-09-01

    To analyse the patency rates of femoro-popliteal stenting with different self-expandable Nitinol stent-designs. Two hundred and twenty-two patients (142 (64%) male; age 72.4 ± 11.6 years) with symptomatic femoro-popliteal peripheral arterial occlusive disease (PAOD) underwent percutaneous transluminal angioplasty (PTA) and stenting with three different Nitinol stents (interwoven IW: n = 70; closed-cell CC: n = 85; open-cell OC: n = 67). One-year post-procedural target lesion revascularization (TLR_12M) rates were investigated with regard to co-morbidities: diabetes (DBM), hyperlipidaemia (HLP), hypertension (RR), coronary artery disease (CAD) and degree of calcification. Twelve-month follow-up data were available for 60, 69 and 50 patients in the IW, OC and CC groups (179 patients in total). The cumulative patency (IW: 52 (86.7%); OC: 50 (72.5%); CC: 23 (46.0%); P stent and the highest TLR_12M for the CC stent. The interwoven stent-design was superior to the standard open- and closed-cell stent-designs in endovascular treatment of femoro-popliteal PAOD in a follow-up period of 12 months. • Results of femoro-popliteal stenting are still unsatisfactory. • Comparative studies for currently available different Nitinol stent-designs are lacking. • This is a first comparative study on long-term patency of different Nitinol stent-designs. • Interwoven stent-design leads to improved long-term patency. • Interwoven stent-design leads to lower TLR than other stent-designs.

  17. Development of tissue-engineered self-expandable aortic stent grafts (Bio stent grafts) using in-body tissue architecture technology in beagles.

    Science.gov (United States)

    Kawajiri, Hidetake; Mizuno, Takeshi; Moriwaki, Takeshi; Ishibashi-Ueda, Hatsue; Yamanami, Masashi; Kanda, Keiichi; Yaku, Hitoshi; Nakayama, Yasuhide

    2015-02-01

    In this study, we aimed to describe the development of tissue-engineered self-expandable aortic stent grafts (Bio stent graft) using in-body tissue architecture technology in beagles and to determine its mechanical and histological properties. The preparation mold was assembled by insertion of an acryl rod (outer diameter, 8.6 mm; length, 40 mm) into a self-expanding nitinol stent (internal diameter, 9.0 mm; length, 35 mm). The molds (n = 6) were embedded into the subcutaneous pouches of three beagles for 4 weeks. After harvesting and removing each rod, the excessive fragile tissue connected around the molds was trimmed, and thus tubular autologous connective tissues with the stent were obtained for use as Bio stent grafts (outer diameter, approximately 9.3 mm in all molds). The stent strut was completely surrounded by the dense collagenous membrane (thickness, ∼150 µm). The Bio stent graft luminal surface was extremely flat and smooth. The graft wall of the Bio stent graft possessed an elastic modulus that was almost two times higher than that of the native beagle abdominal aorta. This Bio stent graft is expected to exhibit excellent biocompatibility after being implanted in the aorta, which may reduce the risk of type 1 endoleaks or migration. © 2014 Wiley Periodicals, Inc.

  18. Stenting of major airway constriction

    International Nuclear Information System (INIS)

    Wu Xiaomei

    2002-01-01

    Objective: To investigate the correlated issues in the stenting treatment of major airway constriction. Methods: Nineteen cases of major airway stenting procedure were studied retrospectively. The clinical choice of stents of different advantages or deficiencies were discussed. The importance of intravenous anesthesia supporting, life-parameters monitoring during the procedures and the prevention of complications were analysed. Results: Under intravenous and local anesthesia, 19 Wallstents had been successively placed and relieved 19 cases of major airway constrictions due to malignant or benign diseases (15 of tumors, 3 of tuberculosis, 1 of tracheomalacia). Intravenous anesthesia and life-parameters monitoring had made the procedures more safe and precise. Conclusions: Major airway stenting is an reliable method for relieving tracheobronchial stenosis; and intravenous anesthesia supporting and life-parameters monitoring guarantee the satisfactions of procedures

  19. Effect of force-induced mechanical stress at the coronary artery bifurcation stenting: Relation to in-stent restenosis

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Cheng-Hung [Division of Cardiology, Department of Internal Medicine, Chang Gung Memorial Hospital, Linkou, Chang Gung University College of Medicine, Tao-Yuan, Taiwan (China); Department of Mechanical Engineering, Chang Gung University, Tao-Yuan, Taiwan (China); Jhong, Guan-Heng [Graduate Institute of Medical Mechatronics, Chang Gung University, Tao-Yuan, Taiwan (China); Hsu, Ming-Yi; Wang, Chao-Jan [Department of Medical Imaging and Intervention, Chang Gung Memorial Hospital, Linkou, Tao-Yuan, Taiwan (China); Liu, Shih-Jung, E-mail: shihjung@mail.cgu.edu.tw [Department of Mechanical Engineering, Chang Gung University, Tao-Yuan, Taiwan (China); Hung, Kuo-Chun [Division of Cardiology, Department of Internal Medicine, Chang Gung Memorial Hospital, Linkou, Chang Gung University College of Medicine, Tao-Yuan, Taiwan (China)

    2014-05-28

    The deployment of metallic stents during percutaneous coronary intervention has become common in the treatment of coronary bifurcation lesions. However, restenosis occurs mostly at the bifurcation area even in present era of drug-eluting stents. To achieve adequate deployment, physicians may unintentionally apply force to the strut of the stents through balloon, guiding catheters, or other devices. This force may deform the struts and impose excessive mechanical stresses on the arterial vessels, resulting in detrimental outcomes. This study investigated the relationship between the distribution of stress in a stent and bifurcation angle using finite element analysis. The unintentionally applied force following stent implantation was measured using a force sensor that was made in the laboratory. Geometrical information on the coronary arteries of 11 subjects was extracted from contrast-enhanced computed tomography scan data. The numerical results reveal that the application of force by physicians generated significantly higher mechanical stresses in the arterial bifurcation than in the proximal and distal parts of the stent (post hoc P < 0.01). The maximal stress on the vessels was significantly higher at bifurcation angle <70° than at angle ≧70° (P < 0.05). The maximal stress on the vessels was negatively correlated with bifurcation angle (P < 0.01). Stresses at the bifurcation ostium may cause arterial wall injury and restenosis, especially at small bifurcation angles. These finding highlight the effect of force-induced mechanical stress at coronary artery bifurcation stenting, and potential mechanisms of in-stent restenosis, along with their relationship with bifurcation angle.

  20. Effect of force-induced mechanical stress at the coronary artery bifurcation stenting: Relation to in-stent restenosis

    International Nuclear Information System (INIS)

    Lee, Cheng-Hung; Jhong, Guan-Heng; Hsu, Ming-Yi; Wang, Chao-Jan; Liu, Shih-Jung; Hung, Kuo-Chun

    2014-01-01

    The deployment of metallic stents during percutaneous coronary intervention has become common in the treatment of coronary bifurcation lesions. However, restenosis occurs mostly at the bifurcation area even in present era of drug-eluting stents. To achieve adequate deployment, physicians may unintentionally apply force to the strut of the stents through balloon, guiding catheters, or other devices. This force may deform the struts and impose excessive mechanical stresses on the arterial vessels, resulting in detrimental outcomes. This study investigated the relationship between the distribution of stress in a stent and bifurcation angle using finite element analysis. The unintentionally applied force following stent implantation was measured using a force sensor that was made in the laboratory. Geometrical information on the coronary arteries of 11 subjects was extracted from contrast-enhanced computed tomography scan data. The numerical results reveal that the application of force by physicians generated significantly higher mechanical stresses in the arterial bifurcation than in the proximal and distal parts of the stent (post hoc P < 0.01). The maximal stress on the vessels was significantly higher at bifurcation angle <70° than at angle ≧70° (P < 0.05). The maximal stress on the vessels was negatively correlated with bifurcation angle (P < 0.01). Stresses at the bifurcation ostium may cause arterial wall injury and restenosis, especially at small bifurcation angles. These finding highlight the effect of force-induced mechanical stress at coronary artery bifurcation stenting, and potential mechanisms of in-stent restenosis, along with their relationship with bifurcation angle.

  1. Self-Expandable Stenting over a Stent Graft for the Exclusion of a Carotid Stump: Troubleshooting for Device Incompatibility

    International Nuclear Information System (INIS)

    Youn, Sung Won; Kim, Ho Kyun; Do, Jin Kook; Kim, Young Whan

    2011-01-01

    Carotid stump, the blind remnant of an occluded internal carotid artery, can be a potential source of microemboli, and warrants its exclusion from the vascular lumen to prevent the recurrence of a microembolism. In a 69-year-old male with a symptomatic carotid stump and acute angle between left common carotid artery and aortic arch, a 7-Fr. shuttle sheath was scarcely placed into the left carotid artery but the 7-mm-diameter stent-graft-loading balloon could not be inserted into the 7-Fr. shuttle sheath. With the mounting a stent graft over a 5-mm balloon, the balloon-expandable stent graft was unfolded. The self-expandable stent was placed over the stent graft, and an 8-mm balloon was subsequently expanded. Self-expanding stenting can be useful for troubleshooting in a case of device incompatibility coming from the different calibers of the external and common carotid arteries for the successful exclusion of a symptomatic carotid stump.

  2. Self-Expandable Stenting over a Stent Graft for the Exclusion of a Carotid Stump: Troubleshooting for Device Incompatibility

    Energy Technology Data Exchange (ETDEWEB)

    Youn, Sung Won; Kim, Ho Kyun [Dept. of Radiology, Catholic University of Daegu School of Medicine, Daegu (Korea, Republic of); Do, Jin Kook [Dept. of Neurology, Catholic University of Daegu School of Medicine, Daegu (Korea, Republic of); Kim, Young Whan [Dept. of Radiology, University College of Medicine, Daegu (Korea, Republic of)

    2011-12-15

    Carotid stump, the blind remnant of an occluded internal carotid artery, can be a potential source of microemboli, and warrants its exclusion from the vascular lumen to prevent the recurrence of a microembolism. In a 69-year-old male with a symptomatic carotid stump and acute angle between left common carotid artery and aortic arch, a 7-Fr. shuttle sheath was scarcely placed into the left carotid artery but the 7-mm-diameter stent-graft-loading balloon could not be inserted into the 7-Fr. shuttle sheath. With the mounting a stent graft over a 5-mm balloon, the balloon-expandable stent graft was unfolded. The self-expandable stent was placed over the stent graft, and an 8-mm balloon was subsequently expanded. Self-expanding stenting can be useful for troubleshooting in a case of device incompatibility coming from the different calibers of the external and common carotid arteries for the successful exclusion of a symptomatic carotid stump.

  3. Complication rate in unprotected carotid artery stenting with closed-cell stents

    International Nuclear Information System (INIS)

    Tietke, Marc W.K.; Kerby, Tina; Alfke, Karsten; Riedel, Christian; Rohr, Axel; Jensen, Ulf; Jansen, Olaf; Zimmermann, Phillip; Stingele, Robert

    2010-01-01

    The discussion on the use of protection devices (PDs) in carotid artery stenting (CAS) is gaining an increasing role in lowering the periprocedural complication rates. While many reviews and reports with retrospective data analysis do promote the use of PDs the most recent multi-centre trials are showing advantages for unprotected CAS combined with closed-cell stent designs. We retrospectively analysed 358 unprotected CAS procedures performed from January 2003 to June 2009 in our clinic. Male/female ratio was 2.68/1. The average age was 69.3 years. Seventy-three percent (261/358) showed initial neurological symptoms. All patients were treated on a standardised interventional protocol. A closed and small-sized cell designed stent was implanted in most cases (85.2%). One hundred seventy-one (47.8%) were controlled by Doppler ultrasonography usually at first in a 3-month and later in 6-month intervals. The peri-interventional and 30-day mortality/stroke rate was 4.19% (15/358). These events included three deaths, five hyperperfusion syndromes (comprising one death by a secondary fatal intracranial haemorrhage), one subarachnoid haemorrhage and seven ischaemic strokes. Only 20% (3/15) of all complications occurred directly peri-interventional. The overall peri-interventional complication rate was 0.8% (3/358). Most complications occurred in initial symptomatic patients (5.36%). The in-stent restenosis rate for more than 70% was 7% (12/171) detected at an average of 9.8 month. Our clinical outcome demonstrates that unprotected CAS with small cell designed stents results in a very low procedural complication rate, which makes the use of a protection device dispensable. (orig.)

  4. Incidence and predictors of coronary stent thrombosis

    DEFF Research Database (Denmark)

    D'Ascenzo, Fabrizio; Bollati, Mario; Clementi, Fabrizio

    2013-01-01

    Stent thrombosis remains among the most feared complications of percutaneous coronary intervention (PCI) with stenting. However, data on its incidence and predictors are sparse and conflicting. We thus aimed to perform a collaborative systematic review on incidence and predictors of stent...

  5. Enterprise stent for waffle-cone stent-assisted coil embolization of large wide-necked arterial bifurcation aneurysms.

    Science.gov (United States)

    Padalino, David J; Singla, Amit; Jacobsen, Walter; Deshaies, Eric M

    2013-01-01

    Large wide-necked arterial bifurcation aneurysms present a unique challenge for endovascular coil embolization treatment. One technique described in the literature deploys a Neuroform stent into the neck of the aneurysm in the shape of a waffle-cone, thereby acting as a scaffold for the coil mass. This case series presents four patients with large wide-necked bifurcation aneurysms treated with the closed-cell Enterprise stent using the waffle-cone technique. Four patients (59 ± 18 years of age) with large wide-necked arterial bifurcation aneurysms (three basilar apex and one MCA bifurcation) were treated with the waffle-cone technique using the Enterprise stent as a supporting device for stent-assisted coil embolization. Three of the patients presented with aneurysmal subarachnoid hemorrhage (Hunt-Hess 2-3; Fisher Grade 3-4). There was no procedural morbidity or mortality associated with treatment itself. One aneurysm was completely obliterated, and three had small residual necks. One patient developed an area of PCA infarct and visual field cut one month after the procedure and required recoiling of the residual neck. The flared ends of the Enterprise stent remodeled the aneurysm neck by conforming to the shape of the neck without any technical difficulty, resulting in a stable scaffold holding the coils into the aneurysm. The closed cell construction, flexibility, and flared ends of the Enterprise stent allow it to conform to the waffle-cone configuration and provide a stable scaffold for coil embolization of large wide-necked arterial bifurcation aneurysms. We have had excellent initial results using the Enterprise stent with the waffle-cone technique. However, this technique is higher risk than standard treatment methods and therefore should be reserved for large wide-necked bifurcation aneurysms where Y stenting is needed, but not possible, and surgical clip ligation is not an option.

  6. Outcomes of secondary self-expandable metal stents versus surgery after delayed initial palliative stent failure in malignant colorectal obstruction.

    Science.gov (United States)

    Yoon, Jin Young; Park, Soo Jung; Hong, Sung Pil; Kim, Tae Il; Kim, Won Ho; Cheon, Jae Hee

    2013-01-01

    When re-intervention is required due to an occluded first colorectal self-expanding metal stent for malignant colorectal obstruction, serious controversies exist regarding whether to use endoscopic re-stenting or surgery. To compare the clinical outcomes in patients who underwent stent re-insertion versus palliative surgery as a second intervention. A total of 115 patients who received either self-expandable metal stent (SEMS) insertion or palliative surgery for treatment of a second occurrence of malignant colorectal obstruction after the first SEMS placement were retrospectively studied between July 2005 and December 2009. The median overall survival (8.2 vs. 15.5 months) and progression-free survival (4.0 vs. 2.7 months) were not significantly different between the stent and surgery groups (p = 0.895 and 0.650, respectively). The median lumen patency in the stent group was 3.4 months and that in the surgery group was 7.9 months (p = 0.003). The immediate complication rate after second stent insertion was 13.9% and late complication rate was observed in 12 of 79 (15.2%) patients. There was no mortality related to the SEMS procedure. The complication and mortality rates associated with palliative surgery were 3.5% (2/57) and 12.3% (7/57), respectively. Although there is no significant difference in the overall survival between stenting and surgery, a secondary stent insertion had a lower mortality rate despite a shorter duration of temporary colorectal decompression compared to that of palliative surgery.

  7. XIENCE V everolimus-eluting coronary stent system: a novel second generation drug-eluting stent

    NARCIS (Netherlands)

    Beijk, Marcel A. M.; Piek, Jon J.

    2007-01-01

    Drug-eluting stents (DES) have been shown to be safe and significantly reduce clinical events and angiographic restenosis in the percutaneous treatment of coronary artery disease. Currently, three DES have been approved in Europe and Northern America: the sirolimus-eluting stent (SES), the

  8. Computational design analysis for deployment of cardiovascular stents

    International Nuclear Information System (INIS)

    Tammareddi, Sriram; Sun Guangyong; Li Qing

    2010-01-01

    Cardiovascular disease has become a major global healthcare problem. As one of the relatively new medical devices, stents offer a minimally-invasive surgical strategy to improve the quality of life for numerous cardiovascular disease patients. One of the key associative issues has been to understand the effect of stent structures on its deployment behaviour. This paper aims to develop a computational model for exploring the biomechanical responses to the change in stent geometrical parameters, namely the strut thickness and cross-link width of the Palmaz-Schatz stent. Explicit 3D dynamic finite element analysis was carried out to explore the sensitivity of these geometrical parameters on deployment performance, such as dog-boning, fore-shortening, and stent deformation over the load cycle. It has been found that an increase in stent thickness causes a sizeable rise in the load required to deform the stent to its target diameter, whilst reducing maximum dog-boning in the stent. An increase in the cross-link width showed that no change in the load is required to deform the stent to its target diameter, and there is no apparent correlation with dog-boning but an increased fore-shortening with increasing cross-link width. The computational modelling and analysis presented herein proves an effective way to refine or optimise the design of stent structures.

  9. Successful treatment of coronary artery pseudoaneurysm by graft stent, which developed after the implantation of bare metal stent

    Directory of Open Access Journals (Sweden)

    Utku Şenol

    2013-03-01

    Full Text Available Although coronary artery pseudoaneurysm which couldoccur following percutaneous coronary interventions is arare complication, it can be mortal. As soon as the pseudoaneurysmis diagnosed, it should be treated by percutaneousintervention or surgery. Graft stent implantationis a preferred treatment for appropriate patients. In thiscase report, we presented a successful treatment of coronaryartery pseudoaneurysm by graft stent; which developedafter the implantation of bare metal stent into theleft anterior descending coronary artery. J Clin Exp Invest2013; 4 (1: 126-129Key words: Coronary artery, pseudoaneurysm, graft stent

  10. Clinical outcomes between different stent designs with the same polymer and drug: comparison between the Taxus Express and Taxus Liberte stents.

    Science.gov (United States)

    Son, Jang-Won; Kim, Ung; Park, Jong-Seon; Kim, Young-Jo; Jang, Jae-Sik; Yang, Tae-Hyun; Kim, Dong-Soo; Kim, Dong-Kie; Seol, Sang-Hoon; Kim, Doo-Il; Nam, Chang-Wook; Hur, Seung-Ho; Kim, Kwon-Bae

    2013-01-01

    The Taxus Liberte stent (Boston Scientific Co.) evolved from the Taxus Express stent, with enhanced stent deliverability and uniform drug delivery. This study was designed to compare angiographic and clinical outcomes in real-world practice between the Taxus Liberte and Taxus Express stents. Between 2006 and 2008, 240 patients receiving the Taxus Liberte stent at three centers were registered and compared to historical control patients who had received the Taxus Express stent (n = 272). After propensity score matching, 173 patients treated with the Taxus Liberte stent and the same number of patients treated with the Taxus Express stent were selected. The primary outcome was a composite of major adverse cardiac events (MACE), including cardiac death, myocardial infarction (MI), ischemia driven target vessel revascularization (TVR), and stent thrombosis (ST) at 1 year. An additional angiographic assessment was conducted at 9 to 12 months. The study showed no significant difference between the Taxus Express and Taxus Liberte stents (death, 1.73% vs. 2.31%, p = 1.000; MI, 0% vs. 1.73%, p = 0.2478; TVR, 2.31% vs. 1.16%, p = 0.6848; and ST, 0% vs. 1.16%, p = 0.4986). The total MACE rate at 1 year did not differ between the groups (4.05% in Taxus Express vs. 4.05% in Taxus Liberte, p = 1.000). In addition, the binary restenosis rate did not differ (2.25% in Taxus Express vs. 1.80% in Taxus Liberte, p = 0.6848). In real-world experience with the two Taxus stent designs, both stents showed similarly good clinical and angiographic outcomes at 1 year. A long-term follow-up study is warranted.

  11. Biolimus-eluting biodegradable polymer-coated stent versus durable polymer-coated sirolimus-eluting stent in unselected patients receiving percutaneous coronary intervention (SORT OUT V)

    DEFF Research Database (Denmark)

    Christiansen, Evald Høj; Jensen, Lisette Okkels; Thayssen, Per

    2013-01-01

    Third-generation biodegradable polymer drug-eluting stents might reduce the risk of stent thrombosis compared with first-generation permanent polymer drug-eluting stents. We aimed to further investigate the effects of a biodegradable polymer biolimus-eluting stent compared with a durable polymer......-coated sirolimus-eluting stent in a population-based setting....

  12. Biodegradable magnesium-alloy stent:current situation in research

    International Nuclear Information System (INIS)

    Chen Hua; Zhao Xianxian

    2011-01-01

    In recent years, permanent metal stents are employed in the majority of interventional therapies; nevertheless, such kind of stents carries the problems of thrombosis and restenosis. Therefore, the biodegradable magnesium alloy stent has become the focus of attention. Theoretically, it has overcome the problems caused by permanent metal stents, so it is the development direction to use the biodegradable magnesium alloy in future. The authors believe that biodegradable magnesium alloy stents will be widely used in interventional procedures for many diseases. (authors)

  13. Role of metallic stents in benign esophageal stricture

    Science.gov (United States)

    Shim, Chan Sup

    2012-10-01

    Simple esophageal strictures, which are focal, straight, and large in diameter, usually require 1 - 3 dilation sessions to relieve symptoms. However, complex strictures, which are long, tortuous, or associated with a severely compromised luminal diameter, are usually more difficult to treat with conventional bougie or balloon dilation techniques, and often have high recurrence rates. Although the permanent placement of self-expandable metal stents (SEMS) has been used to manage refractory benign esophageal strictures, this procedure is associated with additional problems, such as stricture from tissue hyperplasia, stent migration, and fistula formation. Thus, several new types of stents have been developed, including temporary SEMS, self-expandable plastic stents (SEPS), and biodegradable stents. The use of these new products has produced varied results. Temporary SEMS that have been used to relieve benign esophageal conditions have caused granulation tissue at both ends of the stent because of contact between the mucosa and the exposed metal components of the stent, thus hindering stent removal. We examined the tissue response to two new types of SEMS, a flange-type and a straighttype, each coated with a silicone membrane on the outside of the metal mesh. These two SEMS were evaluated individually and compared with a conventional control stent in animal experiments. Although the newly designed stents resulted in reduced tissue hyperplasia, and were thus more easily separated from the esophageal tissue, some degree of tissue hyperplasia did occur. We suggest that newly designed DES (drug-eluting stents) may provide an alternative tool to manage refractory benign esophageal stricture.

  14. Role of Montgomery T-tube stent for laryngotracheal stenosis.

    Science.gov (United States)

    Prasanna Kumar, Saravanam; Ravikumar, Arunachalam; Senthil, Kannan; Somu, Lakshman; Nazrin, Mohd Ismail

    2014-04-01

    To identify the indications, complications and outcome of patients of LTS managed with Montgomery T-tube stenting and review the current literature about the role of stenting in LTS. Retrospective chart reviews of 39 patients of laryngotracheal stenosis managed by T-tube stenting for temporary or definitive treatment during the period 2004-2011 were considered. The data on indications for stenting, type of stent, problems/complications of stenting, duration of stenting, additional intervention and outcome of management were collected, tabulated and analyzed. Of the 51 cases of laryngotracheal stenosis 39 patients were treated by Montgomery T-tube stenting. There was no mortality associated with the procedure or stenting. 82% of the patients were successfully decannulated. The problems and complications encountered were crusting within the tube in 44% and granulation at the subglottis in 33%. Two patients had complication due to T-tube itself: One patient developed tracheomalacia and the other had stenosis at both ends of the T-tube. Stenting still has a role in management of inoperable or in some deadlock situations where resection anastomosis is not feasible. It is easier to introduce the stent and to maintain it. Complications are minor and can be managed easily. It is safe for long term use. We emphasize that the treating surgeon needs to use prudence while treating stenosis using stents. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  15. Endoscopically placed nitinol stents for pediatric tracheal obstruction.

    Science.gov (United States)

    Prasad, Mukesh; Bent, John P; Ward, Robert F; April, Max M

    2002-11-11

    To provide preliminary clinical data regarding endoscopically placed nitinol stents for children with tracheal obstruction as a temporizing measure to allow for trach tube decannulation while awaiting growth to allow for tracheal resection. This case series describes the experiences of two children (ages 5 and 15) who were dependent upon tracheotomy because of acquired tracheal obstruction. Both patients had combined tracheomalacia and tracheal stenosis. After failing tracheoplasty with rib graft augmentation both patients suffered from extensive tracheal disease, which was too long to allow for immediate tracheal resection. Endoscopic placement of nitinol stents in the obstructed tracheal segment using fluoroscopic guidance. All tracheotomy tubes were removed immediately after successful stent deployment with the patient still under general anesthesia. Four stents were placed in total. The first patient's initial stent was too narrow and was, therefore, removed and replaced at a later date with a larger diameter stent. The second patient experienced distal migration of his initial stent requiring stent removal and replacement at a later date. Both patients remain successfully decannulated (follow-up, 25 and 26 months) and are currently living more normal lives as they grow and await tracheal resection. Preliminary use of nitinol stents for pediatric tracheal obstruction has enabled successful decannulation in two children with complicated airways. Our results with this series of patients suggest that nitinol stents can be safely used in children as a temporizing measure until tracheal resection can be safely performed. With this approach children can live free from the hassles of trach care, social isolation and peer ridicule. Limited pediatric experience exists in the literature about nitinol stents. Thus, our experience with stent selection and placement will help others avoid problems encountered in this initial series. Copyright 2002 Elsevier Science Ireland

  16. Endoscopic stenting in bile duct cancer increases liver volume.

    Science.gov (United States)

    Lee, Chang Hun; Kim, Seong Hun; Kim, In Hee; Kim, Sang Wook; Lee, Soo Teik; Kim, Dae Ghon; Yang, Jae Do; Yu, Hee Chul; Cho, Baik Hwan; Lee, Seung Ok

    2014-09-01

    Objective evaluation tools for assessing the effectiveness of stenting in palliative treatment of malignant biliary obstruction are not satisfactory. Effects of biliary stenting on liver volume change have never been studied. We aimed to use volumetry to analyze liver volume changes after endoscopic stenting in bile duct cancer according to the location and number of stents. Retrospective review. University hospital. Patients with a diagnosis of hilar or distal bile duct cancer and who underwent biliary metal stenting. ERCP with self-expandable metal stent placement. Liver volume change after biliary stenting and its comparison according to the location (hilar vs distal common bile duct) and number (hilar bilateral vs hilar unilateral). There were 60 patients; 31 were treated for hilar bile duct cancer (13 for bilateral stent and 18 for unilateral stent) and 29 for distal bile duct cancer. Overall mean follow-up duration was 11.7 ± 4.9 weeks. Liver volume increased 17.4 ± 24.1%. The rate of liver growth was rapid during the early period from 4 to 8 weeks. Stenting in hilar bile duct cancer tended to increase liver volume more than distal biliary stents (22.5% vs 11.9%, P = .091). In hilar bile duct cancer, unilateral and bilateral stents showed similar liver volume increases (20.1% and 25.8%, respectively; P = .512). Single center, retrospective. Biliary stenting markedly increased liver volume in both hilar and distal bile duct cancer. Our data suggest that liver volume assessment could be a useful tool for evaluating stent efficacy. Copyright © 2014 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All rights reserved.

  17. Upper Gastrointestinal Stent Insertion in Malignant and Benign Disorders

    Science.gov (United States)

    Kang, Hyoun Woo

    2015-01-01

    Upper gastrointestinal (GI) stents are increasingly being used to manage upper GI obstructions. Initially developed for palliative treatment of esophageal cancer, upper GI stents now play an emerging role in benign strictures of the upper GI tract. Because recurrent obstruction and stent-related complications are common, new modifications of stents have been implemented. Self-expandable metal stents (SEMS) have replaced older plastic stents. In addition, newly designed SEMS have been developed to prevent complications. This review provides an overview of the various types, indications, methods, complications, and clinical outcomes of upper GI stents in a number of malignant and benign disorders dividing the esophagus and gastroduodenum. PMID:26064817

  18. Technological Advances in Stent Therapies: a Year in Review.

    Science.gov (United States)

    Raffoul, Jad; Nasir, Ammar; Klein, Andrew J P

    2018-04-07

    Stent technology has rapidly evolved since the first stainless steel bare metal stents with substantial developments in scaffolding, polymer, drug choice, drug delivery, and elution mechanisms. Most recently, there has been the evolution of bioabsorbable vascular scaffolds, potentially eliminating the need for long-term foreign object retention. These rapid developments have led to an ever-expanding selection of new stents, making the choice of which to use in which patient challenging. Operators must balance potential short- and long-term clinical ramifications, namely stent thrombosis, in-stent restenosis, target lesion revascularization, and target lesion failure. In this review, we hope to provide insight for interventional cardiologists on the details of stent technology and how this impacts outcomes, stent selection, and duration of dual-antiplatelet therapy duration post drug-eluting stent implantation.

  19. Biodegradable-Polymer Biolimus-Eluting Stents versus Durable-Polymer Everolimus-Eluting Stents at One-Year Follow-Up: A Registry-Based Cohort Study.

    Science.gov (United States)

    Parsa, Ehsan; Saroukhani, Sepideh; Majlessi, Fereshteh; Poorhosseini, Hamidreza; Lofti-Tokaldany, Masoumeh; Jalali, Arash; Salarifar, Mojtaba; Nematipour, Ebrahim; Alidoosti, Mohammad; Aghajani, Hassan; Amirzadegan, Alireza; Kassaian, Seyed Ebrahim

    2016-04-01

    We compared outcomes of percutaneous coronary intervention patients who received biodegradable-polymer biolimus-eluting stents with those who received durable-polymer everolimus-eluting stents. At Tehran Heart Center, we performed a retrospective analysis of the data from January 2007 through December 2011 on 3,270 consecutive patients with coronary artery disease who underwent percutaneous coronary intervention with the biodegradable-polymer biolimus-eluting stent or the durable-polymer everolimus-eluting stent. We excluded patients with histories of coronary artery bypass grafting or percutaneous coronary intervention, acute ST-segment-elevation myocardial infarction, or the implantation of 2 different stent types. Patients were monitored for 12 months. The primary endpoint was a major adverse cardiac event, defined as a composite of death, nonfatal myocardial infarction, and target-vessel and target-lesion revascularization. Durable-polymer everolimus-eluting stents were implanted in 2,648 (81%) and biodegradable-polymer biolimus-eluting stents in 622 (19%) of the study population. There was no significant difference between the 2 groups (2.7% vs 2.7%; P=0.984) in the incidence of major adverse cardiac events. The cumulative adjusted probability of major adverse cardiac events in the biodegradable-polymer biolimus-eluting stent group did not differ from that of such events in the durable-polymer everolimus-eluting stent group (hazard ratio=0.768; 95% confidence interval, 0.421-1.44; P=0.388). We conclude that in our patients the biodegradable-polymer biolimus-eluting stent was as effective and safe, during the 12-month follow-up period, as was the durable-polymer everolimus-eluting stent.

  20. Stent Graft in Managing Juxta-Renal Aortoiliac Occlusion

    International Nuclear Information System (INIS)

    Prabhudesai, V.; Mitra, K.; West, D. J.; Dean, M. R. E.

    2003-01-01

    Endovascular procedures are frequently used as an alternative to surgical bypass in aortic and iliac occlusion. Stents have revolutionized the scope of such endovascular procedures, but there are few reports of stents or stent grafts in occlusive juxta-renal aortic occlusion. We present a case where such occlusion was managed by use of a stent graft with successful outcome

  1. TOKYO criteria 2014 for transpapillary biliary stenting.

    Science.gov (United States)

    Isayama, Hiroyuki; Hamada, Tsuyoshi; Yasuda, Ichiro; Itoi, Takao; Ryozawa, Shomei; Nakai, Yousuke; Kogure, Hirofumi; Koike, Kazuhiko

    2015-01-01

    It is difficult to carry out meta-analyses or to compare the results of different studies of biliary stents because there is no uniform evaluation method. Therefore, a standardized reporting system is required. We propose a new standardized system for reporting on biliary stents, the 'TOKYO criteria 2014', based on a consensus among Japanese pancreatobiliary endoscopists. Instead of stent occlusion, we use recurrent biliary obstruction, which includes occlusion and migration. The time to recurrent biliary obstruction was estimated using Kaplan-Meier analysis with the log-rank test. We can evaluate both plastic and self-expandable metallic stents (uncovered and covered). We also propose specification of the cause of recurrent biliary obstruction, identification of complications other than recurrent biliary obstruction, indication of severity, measures of technical and clinical success, and a standard for clinical care. Most importantly, the TOKYO criteria 2014 allow comparison of biliary stent quality across studies. Because blocked stents can be drained not only using transpapillary techniques but also by an endoscopic ultrasonography-guided transmural procedure, we should devise an evaluation method that includes transmural stenting in the near future. © 2014 The Authors. Digestive Endoscopy © 2014 Japan Gastroenterological Endoscopy Society.

  2. Treatment of Benign and Malignant Tracheobronchial Obstruction with Metal Wire Stents: Experience with a Balloon-Expandable and a Self-Expandable Stent Type

    International Nuclear Information System (INIS)

    Rieger, Johannes; Hautmann, Hubert; Linsenmaier, Ulrich; Weber, Cristoph; Treitl, Markus; Huber, R.M.; Pfeifer, Klaus-Juergen

    2004-01-01

    Over the last few years various types of metal wire stents have been increasingly employed in the treatment of both malignant and benign tracheobronchial obstruction. To date, however, few studies have investigated the in vivo properties of different stent types. We implanted 26 balloon-expandable tantalum Strecker stents (18 patients) and 18 self-expandable Wallstents (16 patients) into the tracheobronchial system of 30 patients with combined stenting in 4 patients. Mean age was 51 years (range: 0.5-79 years). Malignant disease was present in 23 patients, benign disease in seven patients. Both patients and individual stents were monitored clinically and radiographically. The probability of stents remaining within the tracheobronchial system, and of their remaining undislocated and uncompressed was calculated using Kaplan-Meier analysis for both stent types. Average stent follow-up time was 112 days until explantation and 115 days until patients' death or discharge. Kaplan-Meier analysis revealed a higher probability for the Wallstent to remain within the tracheobronchial system. Dislocation and compression occurred more rarely. Explantation, however, if desired, was more difficult compared to the Strecker stent. The Wallstent also led to the formation of granulation tissue, especially at the proximal stent end, frequently requiring reintervention. Both stent types proved to be effective therapeutic options in the management of obstructive tracheobronchial disease. The mechanical properties of the Strecker stent seem to be less favorable compared to the Wallstent but removal is easy. For benign disease, however, the Wallstent reveals limitations due to significant side effects

  3. Risk of Adverse Cardiac and Bleeding Events Following Cardiac and Noncardiac Surgery in Patients With Coronary Stent: How Important Is the Interplay Between Stent Type and Time From Stenting to Surgery?

    Science.gov (United States)

    Saia, Francesco; Belotti, Laura Maria Beatrice; Guastaroba, Paolo; Berardini, Alessandra; Rossini, Roberta; Musumeci, Giuseppe; Tarantini, Giuseppe; Campo, Gianluca; Guiducci, Vincenzo; Tarantino, Fabio; Menozzi, Alberto; Varani, Elisabetta; Santarelli, Andrea; Tondi, Stefano; De Palma, Rossana; Rapezzi, Claudio; Marzocchi, Antonio

    2016-01-01

    Epidemiology and consequences of surgery in patients with coronary stents are not clearly defined, as well as the impact of different stent types in relationship with timing of surgery. Among 39 362 patients with previous coronary stenting enrolled in a multicenter prospective registry and followed for 5 years, 13 128 patients underwent 17 226 surgical procedures. The cumulative incidence of surgery at 30 days, 6 months, 1 year, and 5 years was 3.6%, 9.4%, 14.3%, and 40.0%, respectively, and of cardiac and noncardiac surgery was 0.8%, 2.1%, 2.6%, and 4.0% and 1.3%, 5.1%, 9.1%, and 31.7%, respectively. We assessed the incidence and the predictors of cardiac death, myocardial infarction, and serious bleeding event within 30 days from surgery. Cardiac death occurred in 438 patients (2.5%), myocardial infarction in 256 (1.5%), and serious bleeding event in 1099 (6.4%). Surgery increased 1.58× the risk of cardiac death during follow-up. Along with other risk factors, the interplay between stent type and time from percutaneous coronary intervention to surgery was independently associated with cardiac death/myocardial infarction. In comparison with bare-metal stent implanted >12 months before surgery, old-generation drug-eluting stent was associated with higher risk of events at any time point. Conversely, new-generation drug-eluting stent showed similar safety as bare-metal stent >12 months and between 6 and 12 months and appeared trendly safer between 0 and 6 months. Surgery is frequent in patients with coronary stents and carries a considerable risk of ischemic and bleeding events. Ischemic risk is inversely related with time from percutaneous coronary intervention to surgery and is influenced by stent type. © 2015 American Heart Association, Inc.

  4. [Drug-eluting stent thrombosis and its pharmacological prevention].

    Science.gov (United States)

    Pershukov, I V; Batyraliev, T A

    2007-01-01

    The problem of drug eluting stents (DES) safety has been actively discussed throughout 2006 because of increase of frequency of development of late stent thromboses which were noted during almost 2 years after stenting. In December 2006 US Food and Drug Administration (FDA) advisory panel acknowledged increase of development of late stent thrombosis. At the same time FDA accepted new definition of stent-thrombosis suggested by the Academic Research Consortium. According to this definition thrombosis can be definite, probable and possible. Any unexplained death before end of follow-up in a trial should be considered thrombosis related. Recalculation of thrombosis rate using this definition caused pronounced increase of this parameter in previously conducted trials. Thrombosis rate rose from 0,6 to 3,3% for bare metal stents, from 0,8 to 3,6% for sirolimus eluting stents and from 1,3 to 3,5% for paclitaxel eluting stents. Professional cardiological and angiographical societies (ACC, AHA, SCAI) responding to FDA advisory panel published their proofs and vision of the problem of stent thrombosis. In February 2007 ACC, AHA, SCAI, American College of Surgeons and Association of Dentists published scientific bulletin in which described preventive measures aimed at lowering of risk of thrombosis development. This document contains strict recommendation to continue double antithrombotic therapy with aspirin and clopidogrel for 12 months after implantation of DES or abandonment of the use of this type of stents when long term double antithrombotic therapy is not possible.

  5. Plastic biliary stents for malignant biliary diseases

    NARCIS (Netherlands)

    Huibregtse, Inge; Fockens, Paul

    2011-01-01

    Plastic biliary endoprostheses have not changed much since their introduction more than 3 decades ago. Although their use has been challenged by the introduction of metal stents, plastic stents still remain commonly used. Much work has been done to improve the problem of stent obstruction but

  6. Revascularização endovascular infrainguinal: fatores determinantes para a perviedade Endovascular infrainguinal revascularization: predictive factors for patency

    Directory of Open Access Journals (Sweden)

    Felipe Nasser

    2009-03-01

    Full Text Available Contexto: A terapia endovascular tem avançado muito como tratamento para a doença arterial oclusiva infrainguinal, principalmente com o desenvolvimento dos materiais e dos stents autoexpansíveis de nitinol. Objetivo: Avaliar os resultados e os fatores determinantes da angioplastia fêmoro-poplítea em pacientes portadores de isquemia de membros inferiores. Métodos: Foram tratados, através de angioplastia com ou sem stent, 114 pacientes, e acompanhados por um período médio de 12 meses. A média de idade foi de 66 anos; 53% eram do sexo feminino; 23,7% eram portadores de claudicação incapacitante; 8,8%, de dor isquêmica de repouso; e 67,5%, de lesão trófica. As lesões foram classificadas segundo o TransAtlantic Inter-Society Consensus II em A (53%, B (34%, C (5% e D (9%. Resultados: A análise angiográfica do leito distal mostrou uma média de 1,4±1,0 artérias infrapoplíteas pérvias. O sucesso inicial foi de 97%. No seguimento de 1, 6, 12 e 24 meses, a perviedade primária foi de 94, 78, 48 e 31%, e a primária assistida, de 94, 84, 73 e 61%, respectivamente (p = 0,005. O leito distal pobre e a presença de diabetes melito foram associados a uma menor perviedade primária (p = 0,01, enquanto a extensão da lesão não influenciou os resultados. As taxas de salvamento de membro em 6, 12 e 24 meses foram de 95, 90 e 90%, respectivamente. Conclusões: A extensão das lesões tratadas não foi um fator determinante em nossa casuística para o menor sucesso da angioplastia, o que pode sugerir que as indicações para o tratamento endovascular possam ser ampliadas para pacientes com lesões TransAtlantic Inter-Society Consensus II C/D.Background: Endovascular techniques have undergone major advances with regard to the treatment of infrainguinal arterial occlusive disease, mainly as a result of development of new devices and self-expanding nitinol stents. Objective: To evaluate the results and determinant factors of femoropopliteal

  7. Stent Thrombosis in Drug-Eluting or Bare-Metal Stents in Patients Receiving Dual Antiplatelet Therapy.

    Science.gov (United States)

    Kereiakes, Dean J; Yeh, Robert W; Massaro, Joseph M; Driscoll-Shempp, Priscilla; Cutlip, Donald E; Steg, P Gabriel; Gershlick, Anthony H; Darius, Harald; Meredith, Ian T; Ormiston, John; Tanguay, Jean-François; Windecker, Stephan; Garratt, Kirk N; Kandzari, David E; Lee, David P; Simon, Daniel I; Iancu, Adrian Corneliu; Trebacz, Jaroslaw; Mauri, Laura

    2015-10-01

    This study sought to compare rates of stent thrombosis and major adverse cardiac and cerebrovascular events (MACCE) (composite of death, myocardial infarction, or stroke) after coronary stenting with drug-eluting stents (DES) versus bare-metal stents (BMS) in patients who participated in the DAPT (Dual Antiplatelet Therapy) study, an international multicenter randomized trial comparing 30 versus 12 months of dual antiplatelet therapy in subjects undergoing coronary stenting with either DES or BMS. Despite antirestenotic efficacy of coronary DES compared with BMS, the relative risk of stent thrombosis and adverse cardiovascular events is unclear. Many clinicians perceive BMS to be associated with fewer adverse ischemic events and to require shorter-duration dual antiplatelet therapy than DES. Prospective propensity-matched analysis of subjects enrolled into a randomized trial of dual antiplatelet therapy duration was performed. DES- and BMS-treated subjects were propensity-score matched in a many-to-one fashion. The study design was observational for all subjects 0 to 12 months following stenting. A subset of eligible subjects without major ischemic or bleeding events were randomized at 12 months to continued thienopyridine versus placebo; all subjects were followed through 33 months. Among 10,026 propensity-matched subjects, DES-treated subjects (n = 8,308) had a lower rate of stent thrombosis through 33 months compared with BMS-treated subjects (n = 1,718, 1.7% vs. 2.6%; weighted risk difference -1.1%, p = 0.01) and a noninferior rate of MACCE (11.4% vs. 13.2%, respectively, weighted risk difference -1.8%, p = 0.053, noninferiority p stent thrombosis that are lower than BMS-treated subjects. (The Dual Antiplatelet Therapy Study [DAPT study]; NCT00977938). Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  8. Complications of esophageal stenting after radiotherapy and brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Yorozu, Atsunori; Dokiya, Takushi; Ogita, Mikio; Kutuki, Shoji; Oki, Yosuke [National Second Hospital of Tokyo (Japan)

    1997-11-01

    The purpose of our study was to evaluate safety and complications of stenting after radiotherapy and brachytherapy. Fifteen of 21 patients showed improvement of dysphagia by stenting. But 6 of 21 patients had perforation or massive bleeding relating to stents. The risk for perforation or hemorrhage appears to be even higher in patients who have previously undergone radical radiotherapy and brachytherapy within one month before stenting. Stenting at 6 months or more after radical radiotherapy seems to be an effective and safe method of long-lasting palliation for severe dysphagia with recurrent esophageal cancer. (author)

  9. Scintigraphic examinations after stent implantation in central airways

    International Nuclear Information System (INIS)

    Richter, W.S.; Kettner, B.I.; Munz, D.L.

    1998-01-01

    Endotracheal and endobronchial stent implantation has been developed as an effective treatment of benign and malignant airway stenosis and of tracheo- or bronchoesophageal fistulas. The selection of the stent type depends on the kind and site of disease. Chest X-ray and bronchoscopy are the procedures of choice for monitoring of stent position, structure, and function. However, with scintigraphic methods the effects of stent implantation on pulmonary ventilation and perfusion can be assessed non-invasively. The validation of the effect of a stent implantation on mucociliary and tussive clearance remains to be elucidated. (orig.) [de

  10. Limited Role for Biliary Stent as Surrogate Fiducial Marker in Pancreatic Cancer: Stent and Intratumoral Fiducials Compared

    Energy Technology Data Exchange (ETDEWEB)

    Horst, Astrid van der, E-mail: a.vanderhorst@amc.uva.nl [Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Amsterdam (Netherlands); Lens, Eelco; Wognum, Silvia; Jong, Rianne de [Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Amsterdam (Netherlands); Hooft, Jeanin E. van [Department of Gastroenterology and Hepatology, Academic Medical Center, University of Amsterdam, Amsterdam (Netherlands); Tienhoven, Geertjan van; Bel, Arjan [Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Amsterdam (Netherlands)

    2014-07-01

    Purpose: Because of low soft-tissue contrast of cone beam computed tomography (CBCT), fiducial markers are often used for radiation therapy patient setup verification. For pancreatic cancer patients, biliary stents have been suggested as surrogate fiducials. Using intratumoral fiducials as standard for tumor position, this study aims to quantify the suitability of biliary stents for measuring interfractional and respiratory-induced position variations of pancreatic tumors. Methods and Materials: Eleven pancreatic cancer patients with intratumoral fiducials and a biliary stent were included in this study. Daily CBCT scans (243 in total) were registered with a reference CT scan, based on bony anatomy, on fiducial markers, and on the biliary stent, respectively. We analyzed the differences in tumor position (ie, markers center-of-mass position) among these 3 registrations. In addition, we measured for 9 patients the magnitude of respiratory-induced motion (MM) of the markers and of the stent on 4-dimensional CT (4DCT) and determined the difference between these 2 magnitudes (ΔMM). Results: The stent indicated tumor position better than bony anatomy in 67% of fractions; the absolute difference between the markers and stent registration was >5 mm in 46% of fractions and >10 mm in 20% of fractions. Large PTV margins (superior-inferior direction, >19 mm) would be needed to account for this interfractional position variability. On 4DCT, we found in superior-inferior direction a mean ΔMM of 0.5 mm (range, –2.6 to 4.2 mm). Conclusions: For respiratory-induced motion, the mean ΔMM is small, but for individual patients the absolute difference can be >4 mm. For interfractional position variations, a stent is, on average, a better surrogate fiducial than bony anatomy, but large PTV margins would still be required. Therefore, intratumoral fiducials are recommended for online setup verification for all pancreatic patients scheduled for radiation therapy, including

  11. Endoscopic stenting for hilar cholangiocarcinoma: efficacy of unilateral and bilateral placement of plastic and metal stents in a retrospective review of 480 patients

    Science.gov (United States)

    2012-01-01

    Background Endoscopic biliary drainage of hilar cholangiocarcinoma is controversial with respect to the optimal types of stents and the extent of drainage. This study evaluated endoscopic palliation in patients with hilar cholangiocarcinoma using self-expandable metallic stents (SEMS) and plastic stents (PS).We also compared unilateral and bilateral stent placement according to the Bismuth classification. Methods Data on 480 patients receiving endoscopic biliary drainage for hilar cholangiocarcinoma between September 1995 and December 2010 were retrospectively reviewed to evaluate the following outcome parameters: technical success (TS), functional success (FS), early and late complications, stent patency and survival. Patients were followed from stent insertion until death or stent occlusion. Patients were divided into 3 groups according to the Bismuth classification (Group 1, type I; Group 2, type II; Group 3, type > III). Results The initial stent insertion was successful in 450 (93.8%) patients. TS was achieved in 204 (88.3%) patients treated with PS and in 246 (98.8%) patients palliated with SEMS (p stent patency in weeks (w) were as follows: 20 w in patients palliated with PS and 27 w in patients treated with SEMS (p stent patency. Conclusions SEMS insertion for the palliation of hilar cholangiocarcinoma offers higher technical and clinical success rates in the ITT analysis as well as lower complication rates and a superior cumulative stent patency when compared with PS placement in all Bismuth classifications. The cumulative patency of bilateral SEMS or PS stents was significantly higher than that of unilateral SEMS or PS stents, with lower occlusion rates in Bismuth II patients. PMID:22873816

  12. Self-made Palmaz stent: an experimental swine model study

    International Nuclear Information System (INIS)

    He Shicheng; Teng Gaojun; Guo Jinhe; Fang Wen

    2000-01-01

    Objective: To investigate the histologic changes and physicochemical stability of self-made Palmaz stent placed in swine arteries. Methods: The self-made Palmaz stent was made of 316L stainless steel wire. Nine stents were respectively placed within internal carotid, renal and iliac arteries of six pigs. Pigs were euthanized at intervals of 0.5, 1 and 3 months respectively and angiography were performed. Immediately followed by light and electro scanning microscopy for the stent zones. Results: All stents were successfully implanted in the target arteries and were patent shown in the angiographic examination immediately after the stent placement. Eight stents (8/9) remained patent at the time before euthanasia. No migration of stent were shown in the follow-up angiography. Light and electron scanning microscopy showed that the surface of the stents was covered by a thin layer of endothelial cells 2 weeks after the procedure and completely covered after 4 weeks. No inflammation occurred. Conclusions: The self-made Palmaz stent has good physicochemical stability and histocompatibility with easy placement, rather long term patency, histopathologic stability and thus the promising for clinical application

  13. Mechanical design of an intracranial stent for treating cerebral aneurysms.

    Science.gov (United States)

    Shobayashi, Yasuhiro; Tanoue, Tetsuya; Tateshima, Satoshi; Tanishita, Kazuo

    2010-11-01

    Endovascular treatment of cerebral aneurysms using stents has advanced markedly in recent years. Mechanically, a cerebrovascular stent must be very flexible longitudinally and have low radial stiffness. However, no study has examined the stress distribution and deformation of cerebrovascular stents using the finite element method (FEM) and experiments. Stents can have open- and closed-cell structures, and open-cell stents are used clinically in the cerebrovasculature because of their high flexibility. However, the open-cell structure confers a risk of in-stent stenosis due to protrusion of stent struts into the normal parent artery. Therefore, a flexible stent with a closed-cell structure is required. To design a clinically useful, highly flexible, closed-cell stent, one must examine the mechanical properties of the closed-cell structure. In this study, we investigated the relationship between mesh patterns and the mechanical properties of closed-cell stents. Several mesh patterns were designed and their characteristics were studied using numerical simulation. The results showed that the bending stiffness of a closed-cell stent depends on the geometric configuration of the stent cell. It decreases when the stent cell is stretched in the circumferential direction. Mechanical flexibility equal to an open-cell structure was obtained in a closed-cell structure by varying the geometric configuration of the stent cell. Copyright © 2010 IPEM. Published by Elsevier Ltd. All rights reserved.

  14. Atrial septal stenting - How I do it?

    Directory of Open Access Journals (Sweden)

    Kothandam Sivakumar

    2015-01-01

    Full Text Available A wide atrial communication is important to maintain hemodynamics in certain forms of congenital and acquired heart defects. In comparison to balloon septostomy or blade septostomy, atrial septal stenting provides a controlled, predictable, and long-lasting atrial communication. It often needs a prior Brockenbrough needle septal puncture to obtain a stable stent position. A stent deployed across a previously dilated and stretched oval foramen or tunnel form of oval foramen carries higher risk of embolization. This review provides technical tips to achieve a safe atrial septal stenting. Even though this is a "How to do it article," an initial discussion about the indications for atrial septal stenting is vital as the resultant size of the atrial septal communication should be tailored for each indication.

  15. Classic crush and DK crush stenting techniques.

    Science.gov (United States)

    Zhang, Jun-Jie; Chen, Shao-Liang

    2015-01-01

    Clinical data have supported the advantages of the double kissing (DK) crush technique, which consists of stenting the side branch (SB), balloon crush, first kissing, stenting the main vessel (MV) and final kissing balloon inflation, for complex coronary bifurcation lesions compared to other stenting techniques. Careful rewiring from the proximal cell of the MV stent to make sure the wire is in the true lumen of the SB stent is key to acquiring optimal angiographic results. Balloon anchoring from the MV, alternative inflation and each kissing inflation using large enough non-compliant balloons at high pressure, and the proximal optimisation technique are mandatory to improve both angiographic and clinical outcomes. Stratification of a given bifurcation lesion is recommended before decision making.

  16. Tracheal Self-Expandable Metallic Stents: A Comparative Study of Three Different Stents in a Rabbit Model.

    Science.gov (United States)

    Serrano, Carolina; Lostalé, Fernando; Rodríguez-Panadero, Francisco; Blas, Ignacio de; Laborda, Alicia; de Gregorio, Miguel Angel

    2016-03-01

    The objective of this study was to assess tracheal reactivity after the deployment of different self-expandable metal stents (SEMS). Forty female New Zealand rabbits were divided into four groups. Three groups received three different SEMS: steel (ST), nitinol (NiTi), or nitinol drug-eluting stent (DES); the fourth group was the control group (no stent). Stents were deployed percutaneously under fluoroscopic guidance. Animals were assessed by multi-slice, computed tomography (CT) scans, and tracheas were collected for anatomical pathology (AP) study. Data from CT and AP were statistically analyzed and correlated. The DES group had the longest stenosis (20.51±14.08mm vs. 5.84±12.43 and 6.57±6.54mm in NiTi and ST, respectively, day 30; Pstent. CT was more effective in detecting wall thickening (positive correlation of 68.9%; Pstent, while DES caused significant lesions that may be related to drug dosage. This type of DES stent is therefore not recommended for the treatment of tracheobronchial stenosis. Copyright © 2015 SEPAR. Published by Elsevier Espana. All rights reserved.

  17. Risk Factors for Migration, Fracture, and Dislocation of Pancreatic Stents

    Directory of Open Access Journals (Sweden)

    Yoshiaki Kawaguchi

    2015-01-01

    Full Text Available Aim. To analyze the risk factors for pancreatic stent migration, dislocation, and fracture in chronic pancreatitis patients with pancreatic strictures. Materials and Methods. Endoscopic stent placements (total 386 times were performed in 99 chronic pancreatitis patients with pancreatic duct stenosis at our institution between April 2006 and June 2014. We retrospectively examined the frequency of stent migration, dislocation, and fracture and analyzed the patient factors and stent factors. We also investigated the retrieval methods for migrated and fractured stents and their success rates. Results. The frequencies of stent migration, dislocation, and fracture were 1.5% (5/396, 0.8% (3/396, and 1.2% (4/396, respectively. No significant differences in the rates of migration, dislocation, or fracture were noted on the patient factors (etiology, cases undergoing endoscopic pancreatic sphincterotomy, location of pancreatic duct stenosis, existence of pancreatic stone, and approach from the main or minor papilla and stent factors (duration of stent placement, numbers of stent placements, stent shape, diameter, and length. Stent retrieval was successful in all cases of migration. In cases of fractured stents, retrieval was successful in 2 of 4 cases. Conclusion. Stent migration, fracture, and dislocation are relatively rare, but possible complications. A good understanding of retrieval techniques is necessary.

  18. Three-year patient-related and stent-related outcomes of second-generation everolimus-eluting Xience V stents versus zotarolimus-eluting resolute stents in real-world practice (from the Multicenter Prospective EXCELLENT and RESOLUTE-Korea Registries).

    Science.gov (United States)

    Lee, Joo Myung; Park, Kyung Woo; Han, Jung-Kyu; Yang, Han-Mo; Kang, Hyun-Jae; Koo, Bon-Kwon; Bae, Jang-Whan; Woo, Sung-Il; Park, Jin Sik; Jin, Dong-Kyu; Jeon, Dong Woon; Oh, Seok Kyu; Park, Jong-Seon; Kim, Doo-Il; Hyon, Min Su; Jeon, Hui-Kyung; Lim, Do-Sun; Kim, Myeong-Gon; Rha, Seung-Woon; Her, Sung-Ho; Hwang, Jin-Yong; Kim, Sanghyun; Choi, Young Jin; Kang, Jin Ho; Moon, Keon-Woong; Jang, Yangsoo; Kim, Hyo-Soo

    2014-11-01

    Long-term outcomes are imperative to confirm safety of drug-eluting stents. There have been 2 randomized controlled trials comparing everolimus-eluting stents (EESs) and Resolute zotarolimus-eluting stents (ZES-Rs). To date, long-term clinical outcomes of these stents were limited to only 1 report, which has recently reported 4-year comparisons of these stents. Therefore, more evidence is needed regarding long-term clinical outcomes of the second-generation stents. This study compared the long-term clinical outcomes of EES with ZES-R in "all-comer" cohorts up to 3-year follow-up. The EXCELLENT and RESOLUTE-Korea registries prospectively enrolled 3,056 patients treated with EES and 1,998 with ZES-R, respectively, without exclusions. Stent-related composite outcomes (target lesion failure) and patient-related composite events up to 3-year follow-up were compared in crude and propensity score-matched analyses. Of 5,054 patients, 3,830 patients (75.8%) had off-label indication (2,217 treated with EES and 1,613 treated with ZES-R). The stent-related outcome (189 [6.2%] vs 127 [6.4%], p = 0.812) and the patient-related outcome (420 [13.7%] vs 250 [12.5%], p = 0.581) did not differ between EES and ZES-R, respectively, at 3 years, which was corroborated by similar results from the propensity score-matched cohort (hazard ratio [HR] 0.92, 95% confidence interval [CI] 0.70 to 1.20, p = 0.523 and 0.85, 95% CI 0.70 to 1.02, p = 0.081, for stent- and patient-related outcomes, respectively). The rate of definite or probable stent thrombosis up to 3 years (22 [0.7%] vs 10 [0.5%], p = 0.370) was also similar. The rate of very late definite or probable stent thrombosis was very low and comparable between the 2 stents (3 [0.1%] vs 1 [0.1%], p = 0.657). In multivariate analysis, chronic renal failure (adjusted HR 3.615, 95% CI 2.440 to 5.354, p stents showed comparable safety and efficacy at 3-year follow-up in this robust real-world registry with unrestricted use of EES and

  19. Ureteral stent discomfort: Etiology and management

    Directory of Open Access Journals (Sweden)

    Ricardo Miyaoka

    2009-01-01

    Full Text Available Objectives : To review the evidence-based literature on the causes, characteristics, and options to manage double J stent-related symptoms. Methods : We performed a Medline database assessment on papers that investigated the prevalence, mechanisms, risk factors, bothersome and management of double-J stent-related symptoms. Articles in English were reviewed and summarized. Results : Stent-related symptoms have a high prevalence and may affect over 80% of patients. They include irritative voiding symptoms including frequency, urgency, dysuria, incomplete emptying; flank and suprapubic pain; incontinence, and hematuria. Assessment tools are important to determine their intensity and allow for comparisons between different points in the timeline. The Urinary Stent Symptom Questionnaire (USSQ is the most proper tool used for this purpose. Management should be focused on the prevention and management of symptoms. In this sense, research has focused on new materials and stent designs that would be more compatible to the physiologic properties of the urinary tract and medications that can ameliorate the sensitivity and motor response of the bladder. Conclusions : Stent-related symptoms are very common in the Urological clinical setting. It is of major importance for the urologist to understand their physiopathology and to be familiar with ways to avoid or manage them.

  20. Impact of an endothelial progenitor cell capturing stent on coronary microvascular function: comparison with drug-eluting stents.

    Science.gov (United States)

    Choi, Woong Gil; Kim, Soo Hyun; Yoon, Hyung Seok; Lee, Eun Joo; Kim, Dong Woon

    2015-01-01

    Although drug-eluting stents (DESs) effectively reduce restenosis following percutaneous coronary intervention (PCI), they also delay re-endothelialization and impair microvascular function, resulting in adverse clinical outcomes. Endothelial progenitor cell (EPC) capturing stents, by providing a functional endothelial layer on the stent, have beneficial effects on microvascular function. However, data on coronary microvascular function in patients with EPC stents versus DESs are lacking. Seventy-four patients who previously underwent PCI were enrolled in this study. Microvascular function was evaluated 6 months after PCI based on the index of microvascular resistance (IMR) and the coronary flow reserve (CFR). IMR was calculated as the ratio of the mean distal coronary pressure at maximal hyperemia to the inverse of the hyperemic mean transit time (hTmn). The CFR was calculated by dividing the hTmn by the baseline mean transit time. Twenty-one patients (age, 67.2 ± 9.6 years; male:female, 15:6) with an EPC stent and 53 patients (age, 61.5 ± 14.7 years; male:female, 40:13) with second-generation DESs were included in the study. There were no significant differences in the baseline clinical and angiographic characteristics of the two groups. Angiography performed 6 months postoperatively did not show significant differences in their CFR values. However, patients with the EPC stent had a significantly lower IMR than patients with second-generation DESs (median, 25.5 [interquartile range, 12.85 to 28.18] vs. 29.0 [interquartile range, 15.42 to 39.23]; p = 0.043). Microvascular dysfunction was significantly improved after 6 months in patients with EPC stents compared to those with DESs. The complete re-endothelialization achieved with the EPC stent may provide clinical benefits over DESs, especially in patients with microvascular dysfunction.

  1. Effect of biolimus-eluting stents with biodegradable polymer vs bare-metal stents on cardiovascular events among patients with acute myocardial infarction

    DEFF Research Database (Denmark)

    Räber, Lorenz; Kelbæk, Henning; Ostojic, Miodrag

    2012-01-01

    The efficacy and safety of drug-eluting stents compared with bare-metal stents remains controversial in patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI).......The efficacy and safety of drug-eluting stents compared with bare-metal stents remains controversial in patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI)....

  2. A review on biodegradable materials for cardiovascular stent application

    Science.gov (United States)

    Hou, Li-Da; Li, Zhen; Pan, Yu; Sabir, MuhammadIqbal; Zheng, Yu-Feng; Li, Li

    2016-09-01

    A stent is a medical device designed to serve as a temporary or permanent internal scaffold to maintain or increase the lumen of a body conduit. The researchers and engineers diverted to investigate biodegradable materials due to the limitation of metallic materials in stent application such as stent restenosis which requires prolonged anti platelet therapy, often result in smaller lumen after implantation and obstruct re-stenting treatments. Biomedical implants with temporary function for the vascular intervention are extensively studied in recent years. The rationale for biodegradable stent is to provide the support for the vessel in predicted period of time and then degrading into biocompatible constituent. The degradation of stent makes the re-stenting possible after several months and also ameliorates the vessel wall quality. The present article focuses on the biodegradable materials for the cardiovascular stent. The objective of this review is to describe the possible biodegradable materials for stent and their properties such as design criteria, degradation behavior, drawbacks and advantages with their recent clinical and preclinical trials.

  3. Percutaneous nephrostomy and antegrade ureteral stenting: technique - indications - complications

    Energy Technology Data Exchange (ETDEWEB)

    Hausegger, Klaus A. [Klagenfurt General Hospital, Department of Radiology, Klagenfurt (Austria); Portugaller, Horst R. [University Hospital of Graz, Department of Radiology, Graz (Austria)

    2006-09-15

    In this review the technique, indication for and complications of percutaneous nephrostomy (PCN) and antegrade ureter stent insertion are described. In the majority of the cases PCN is performed to relieve urinary obstruction, which can be of benign or malignant nature. Another indication for PCN is for treatment of urinary fistulas. PCN can be performed under ultrasound and/or fluoroscopic guidance, with a success rate of more than 90%. The complication rate is approximately 10% for major and minor complications together and 4-5% for major complications only. Percutaneous antegrade double-J stent insertion usually is performed if retrograde ureter stenting has not been successful. However, especially in malignant obstructions, the success rate for antegrade stenting is higher than for retrograde transvesical double-J stent insertion. In the case of severe infection and bleeding after PCN JJ-stent insertion may be contraindicated so long as there is no sufficient concomitant drainage via a PCN. Lower urinary tract dysfunction should be excluded before stent placement. The complication rate is 2-4%. Consequent stent surveillance with regular stent exchange is mandatory. (orig.)

  4. Crossing Y-stent technique with dual open-cell stents for coiling of wide-necked bifurcation aneurysms.

    Science.gov (United States)

    Ko, Jun Kyeung; Han, In Ho; Cho, Won Ho; Choi, Byung Kwan; Cha, Seung Heon; Choi, Chang Hwa; Lee, Sang Weon; Lee, Tae Hong

    2015-05-01

    Double stenting in a Y-configuration is a promising therapeutic option for wide-necked cerebral aneurysms not amenable to reconstruction with a single stent. We retrospectively evaluated the efficacy and safety of the crossing Y-stent technique for coiling of wide-necked bifurcation aneurysms. By collecting clinical and radiological data we evaluated from January 2007 through December 2013, 20 wide-necked bifurcation aneurysms. Twelve unruptured and eight ruptured aneurysms in 20 patients were treated with crossing Y-stent-assisted coiling. Aneurysm size and neck size ranged from 3.2 to 28.2mm (mean 7.5mm) and from 1.9 to 9.1mm (mean 4.5mm). A Y-configuration was established successfully in all 20 patients. All aneurysms were treated with a pair of Neuroform stents. The immediate angiographic results were total occlusion in 17 aneurysms, residual neck in two, and residual sac in one. Peri-operative morbidity was only 5%. Fifteen of 18 surviving patients underwent follow-up conventional angiography (mean, 10.9 months). The result showed stable occlusion in all 15 aneurysms and asymptomatic in-stent occlusion in one branch artery. At the end of the observation period (mean, 33.5 months), all 12 patients without subarachnoid hemorrhage had excellent clinical outcomes (mRS 0), except one (mRS 2). Of eight patients with subarachnoid hemorrhage, four remained symptom free (mRS 0), while the other four had were dependent or dead (mRS score, 3-6). In this report on 20 patients, crossing Y-stent technique for coiling of wide-necked bifurcation aneurysms showed a good technical safety and favorable clinical and angiographic outcome. Copyright © 2015. Published by Elsevier B.V.

  5. Complications related to conventional self-expandable metal stent insertion and internal irradiation stent insertion in patients with advanced esophageal carcinoma: an analysis of 32 cases

    International Nuclear Information System (INIS)

    Xu Xingwen; Di Haiting; Zhu Jun; Shi Jian

    2011-01-01

    Objective: To compare the occurrence of complications between conventional self-expandable metal stent and internal irradiation stent insertion in treating patients with advanced esophageal carcinomas. Methods: A total of 32 patients with advanced esophageal carcinoma were randomly divided into irradiation stent group (n=15) and conventional stent group (n=17). Internal irradiation stent loaded with 125 I seeds was employed in patients of irradiation stent group, while conventional self-expandable metal stent was used in patients of conventional stent group. After the treatment, clinical follow-up was regularly conducted. Postoperative complications such as fever, severe chest pain, cough, esophageal perforation, pneumonia, hemorrhage, stent migration and restenosis, etc. were observed. Results: No significant difference in the occurrence of fever, severe chest pain, esophageal perforation and hemorrhage existed between the two groups (P>0.05). The difference in the occurrence of long-term complications such as stent migration or restenosis between the two groups was out statistically significant (P>0.05). However, the restenosis in irradiation stent group occurred obviously much later than that in conventional stent group. Conclusion: For the treatment of advanced esophageal carcinomas, the insertion of internal irradiation esophageal stent is safe. It dose not increase the incidence of postoperative complications. Therefore, it is worth popularizing this technique in clinical practice. (authors)

  6. Optical coherence tomography at follow-up after percutaneous coronary intervention: relationship between procedural dissections, stent strut malapposition and stent healing

    DEFF Research Database (Denmark)

    Radu, Maria; Jørgensen, Erik; Kelbæk, Henning

    2011-01-01

    To analyse the relationship between strut apposition as visualised with optical coherence tomography (OCT) at follow-up and clinical and procedural characteristics at stent implantation, and to examine the relationship between strut apposition and stent healing.......To analyse the relationship between strut apposition as visualised with optical coherence tomography (OCT) at follow-up and clinical and procedural characteristics at stent implantation, and to examine the relationship between strut apposition and stent healing....

  7. Stent sizing strategies in renal artery stenting: the comparison of conventional invasive renal angiography with renal computed tomographic angiography.

    Science.gov (United States)

    Kadziela, Jacek; Michalowska, Ilona; Pregowski, Jerzy; Janaszek-Sitkowska, Hanna; Lech, Katarzyna; Kabat, Marek; Staruch, Adam; Januszewicz, Andrzej; Witkowski, Adam

    2016-01-01

    Randomized trials comparing invasive treatment of renal artery stenosis with standard pharmacotherapy did not show substantial benefit from revascularization. One of the potential reasons for that may be suboptimal procedure technique. To compare renal stent sizing using two modalities: three-dimensional renal computed tomography angiography (CTA) versus conventional angiography. Forty patients (41 renal arteries), aged 65.1 ±8.5 years, who underwent renal artery stenting with preprocedural CTA performed within 6 months, were retrospectively analyzed. In CTA analysis, reference diameter (CTA-D) and lesion length (CTA_LL) were measured and proposed stent diameter and length were recorded. Similarly, angiographic reference diameter (ANGIO_D) and lesion length (ANGIO_LL) as well as proposed stent dimensions were obtained by visual estimation. The median CTA_D was 0.5 mm larger than the median ANGIO_D (p < 0.001). Also, the proposed stent diameter in CTA evaluation was 0.5 mm larger than that in angiography (p < 0.0001). The median CTA_LL was 1 mm longer than the ANGIO_LL (p = NS), with significant correlation of these variables (r = 0.66, p < 0.0001). The median proposed stent length with CTA was equal to that proposed with angiography. The median diameter of the implanted stent was 0.5 mm smaller than that proposed in CTA (p < 0.0005) and identical to that proposed in angiography. The median length of the actual stent was longer than that proposed in angiography (p = 0.0001). Renal CTA has potential advantages as a tool adjunctive to angiography in appropriate stent sizing. Careful evaluation of the available CTA scans may be beneficial and should be considered prior to the planned procedure.

  8. Successful Expansion of an Underexpanded Stent by Rotational Atherectomy

    Science.gov (United States)

    Vales, Lori; Coppola, John; Kwan, Tak

    2013-01-01

    The current routine use of intracoronary stents in percutaneous coronary intervention (PCI) has significantly reduced rates of restenosis, compared with balloon angioplasty alone. On the contrary, small post-stenting luminal dimensions due to undilatable, heavily calcified plaques have repeatedly been shown to significantly increase the rates of in-stent restenosis. Rotational atherectomy of lesions is an alternative method to facilitate PCI and prevent underexpansion of stents, when balloon angioplasty fails to successfully dilate a lesion. Stentablation, using rotational atherectomy to expand underexpanded stents deployed in heavily calcified plaques, has also been reported. We report a case via the transradial approach of rotational-atherectomy–facilitated PCI of in-stent restenosis of a severely underexpanded stent due to a heavily calcified plaque. We review the literature and suggest rotational atherectomy may have a role in treating a refractory, severely underexpanded stent caused by a heavily calcified plaque through various proposed mechanisms. PMID:24436587

  9. The current role of vascular stents.

    Science.gov (United States)

    Busquet, J

    1993-09-01

    The limitations of percutaneous balloon angioplasty have favoured the development and the use of vascular endoprostheses or stents. These thin-walled metal devices maintain after expansion, an optimal and constant diameter for the vascular lumen. Restenosis, dissection, abrupt closure, residual stenosis or re-opened total occlusion represent appropriate indications for stenting. A large experience with non-coronary application of stents is currently available in iliac, femoro-popliteal and renal arteries, aorta, large veins.

  10. Role of stents and laser therapy in biliary strictures

    Science.gov (United States)

    Chennupati, Raja S.; Trowers, Eugene A.

    2001-05-01

    The most frequent primary cancers causing malignant obstructive jaundice were pancreatic cancer (57%), hilar biliary cancer (19% including metastatic disease), nonhilar biliary cancer (14%) and papillary cancer (10%). Endoscopic stenting has widely replaced palliative surgery for malignant biliary obstruction because of its lower risk and cost. Self-expandable metal stents are the preferred mode of palliation for hilar malignancies. Plastic stents have a major role in benign biliary strictures. Major complications and disadvantages associated with metallic stents include high cost, cholangitis. malposition, migration, unextractability, and breakage of the stents, pancreatitis and stent dysfunction. Dysfunction due to tumor ingrowth can be relieved by thermal methods (argon plasma coagulator therapy). We present a concise review of the efficacy of metallic stents for palliation of malignant strictures.

  11. Experimental use of new absorbable tracheal stent.

    Science.gov (United States)

    Schopf, Luciano F; Fraga, José Carlos; Porto, Rodrigo; Santos, Luis A; Marques, Douglas R; Sanchez, Paulo R; Meyer, Fabíola S; Ulbrich, Jane M

    2017-11-16

    Silicone and metallic stents are not effective in children with tracheobronchial stenosis or tracheomalacia. Herein, we aimed to evaluate the clinical manifestations and histological reaction of rabbit trachea to the presence of a new poly(lactic-co-glycolic acid) with polyisoprene (PLGA/PI) polymer absorbable stent. Fourteen adult white rabbits (weight, 3.0-3.5kg) were randomly assigned to three groups: Group I (n=6): PLGA/PI spiral stent; Group II (n=6): PLGA/PI fragment; and Group III (n=2): controls. After a longitudinal incision on three cervical tracheal rings, the stents and fragments were inserted into the trachea and fixed onto the lateral wall with nonabsorbable sutures. The stented group showed significantly more stridor at rest (p=0.0041), agitation (p=0.014), and use of accessory muscles (p=0.0002) and required more emergency endoscopies than the fragment group. Further, it showed significantly more remarkable histological inflammatory damage than the fragment and control groups (p=0.002). The new PLGA/PI polymeric stent implanted into the trachea of rabbits caused more clinical manifestations and histologically verified inflammatory reaction than the PLGA/PI polymeric fragment. Future studies should be aimed at reducing the stent-wall thickness. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Metallic Stents for Tracheobronchial Pathology Treatment

    International Nuclear Information System (INIS)

    Serrano, Carolina; Laborda, Alicia; Lozano, Juan M.; Caballero, Hugo; Sebastián, Antonio; Lopera, Jorge; Gregorio, Miguel Ángel de

    2013-01-01

    Purpose: To present the 7-year experience of the treatment of benign and malignant tracheobronchial stenoses using metallic stents. Patients and Methods: One hundred twenty-three stents were inserted in 86 patients (74 benign and 12 malignant stenoses). Ninety-seven stents were placed in the trachea and 26 in the bronchi. The procedures were performed under fluoroscopic and flexible bronchoscopic guidance with the patient under light sedation. In cases of severe stenotic lesions or obstructions, laser resection was performed before stent placement. Clinical and functional pulmonary data were recorded before and 3 months after the procedure. Follow-up involved clinical data and radiographic techniques at 48 h and at 1-, 3-, 6-, and 12-month intervals. Results: The technical success was 100 %. Dyspnea disappearance, forced expiratory volume in the first second, and pulmonary functional data improvement was observed in all patients (p < 0.001). Complications were detected in 23 patients (26.7 %). Mean follow-up time was 6.3 ± 1.2 months in patients with malignant lesions and 76.2 ± 2.3 months patients with in benign lesions. By the end of the study, 100 % of patients with malignant pathology and 6.7 % of patients with benign lesions had died. Conclusion: Endoluminal treatment of tracheobronchial stenosis with metallic stents is a therapeutic alternative in patients who are poor candidates for surgery. In unresectable malignant lesions, the benefit of metallic stenting is unquestionable. In benign lesions, the results are satisfactory, but sometimes other interventions are required to treat complications. New stent technology may improve these results

  13. Metallic stents for tracheobronchial pathology treatment.

    Science.gov (United States)

    Serrano, Carolina; Laborda, Alicia; Lozano, Juan M; Caballero, Hugo; Sebastián, Antonio; Lopera, Jorge; de Gregorio, Miguel Ángel

    2013-12-01

    To present the 7-year experience of the treatment of benign and malignant tracheobronchial stenoses using metallic stents. One hundred twenty-three stents were inserted in 86 patients (74 benign and 12 malignant stenoses). Ninety-seven stents were placed in the trachea and 26 in the bronchi. The procedures were performed under fluoroscopic and flexible bronchoscopic guidance with the patient under light sedation. In cases of severe stenotic lesions or obstructions, laser resection was performed before stent placement. Clinical and functional pulmonary data were recorded before and 3 months after the procedure. Follow-up involved clinical data and radiographic techniques at 48 h and at 1-, 3-, 6-, and 12-month intervals. The technical success was 100 %. Dyspnea disappearance, forced expiratory volume in the first second, and pulmonary functional data improvement was observed in all patients (p < 0.001). Complications were detected in 23 patients (26.7 %). Mean follow-up time was 6.3 ± 1.2 months in patients with malignant lesions and 76.2 ± 2.3 months patients with in benign lesions. By the end of the study, 100 % of patients with malignant pathology and 6.7 % of patients with benign lesions had died. Endoluminal treatment of tracheobronchial stenosis with metallic stents is a therapeutic alternative in patients who are poor candidates for surgery. In unresectable malignant lesions, the benefit of metallic stenting is unquestionable. In benign lesions, the results are satisfactory, but sometimes other interventions are required to treat complications. New stent technology may improve these results.

  14. Metallic Stents for Tracheobronchial Pathology Treatment

    Energy Technology Data Exchange (ETDEWEB)

    Serrano, Carolina, E-mail: carolina.serrano@unizar.es [University of Zaragoza, Surgical Pathology Unit, Animal Pathology Department (Spain); Laborda, Alicia, E-mail: alaborda@unizar.es [University of Zaragoza, Minimally Invasive Techniques Research Group (GITMI) (Spain); Lozano, Juan M., E-mail: juamauloz@gmail.com [Marly Clinic, Radiology Department (Colombia); Caballero, Hugo, E-mail: hugocaballero2007@gmail.com [Marly Clinic, Pulmonology Department (Colombia); Sebastian, Antonio, E-mail: antonio.sebastian@ono.es [Lozano Blesa Clinical University Hospital, Pulmonology Department (Spain); Lopera, Jorge, E-mail: lopera@uthscsa.edu [Health Science Center, Interventional Radiology Deparment (United States); Gregorio, Miguel Angel de, E-mail: mgregori@unizar.es [University of Zaragoza, Minimally Invasive Techniques Research Group (GITMI) (Spain)

    2013-12-15

    Purpose: To present the 7-year experience of the treatment of benign and malignant tracheobronchial stenoses using metallic stents. Patients and Methods: One hundred twenty-three stents were inserted in 86 patients (74 benign and 12 malignant stenoses). Ninety-seven stents were placed in the trachea and 26 in the bronchi. The procedures were performed under fluoroscopic and flexible bronchoscopic guidance with the patient under light sedation. In cases of severe stenotic lesions or obstructions, laser resection was performed before stent placement. Clinical and functional pulmonary data were recorded before and 3 months after the procedure. Follow-up involved clinical data and radiographic techniques at 48 h and at 1-, 3-, 6-, and 12-month intervals. Results: The technical success was 100 %. Dyspnea disappearance, forced expiratory volume in the first second, and pulmonary functional data improvement was observed in all patients (p < 0.001). Complications were detected in 23 patients (26.7 %). Mean follow-up time was 6.3 {+-} 1.2 months in patients with malignant lesions and 76.2 {+-} 2.3 months patients with in benign lesions. By the end of the study, 100 % of patients with malignant pathology and 6.7 % of patients with benign lesions had died. Conclusion: Endoluminal treatment of tracheobronchial stenosis with metallic stents is a therapeutic alternative in patients who are poor candidates for surgery. In unresectable malignant lesions, the benefit of metallic stenting is unquestionable. In benign lesions, the results are satisfactory, but sometimes other interventions are required to treat complications. New stent technology may improve these results.

  15. Esophageal stent migration can lead to intestinal obstruction

    Science.gov (United States)

    Karatepe, Oguzhan; Acet, Ersin; Altiok, Merih; Battal, Muharrem; Adas, Gokhan; Karahan, Servet

    2009-01-01

    Background: Self-expanding metallic stents are the devices of choice in the treatment of malign or benign strictures of the esophagus. Stent migration is a well-known complication of this procedure. Aims: We report a case of intestinal obstruction caused by esophageal stent migration, in which surgical intervention was used. Methods: A 65-year-old woman, who had a medical history of gastric cancer operations and esophageal stent applications, was admitted to our emergency department with a 48-hour history of abdominal pain, nausea and vomiting. An emergency laparotomy was performed and the migrated stent causing intestinal obstruction was removed. Results: The patient recovered without incident and was discharged on postoperative day 3. Conclusion: This case illustrates that esophageal stent migration has to be considered as a potential life-threatening complication. PMID:22666672

  16. An experimental study on expandable endovascular metallic stents in dogs

    Energy Technology Data Exchange (ETDEWEB)

    Song, Ho Young; Kim, Hak Nam [Chonbuk National University College of Medicine, Chonju (Korea, Republic of)

    1990-12-15

    We constructed an expandable endovascular metallic stent in the same way as Giamturco did. Experiments were made to test the ability of these stents to be used in the vessels. A total of 20 stents were passed through a 8.5 French teflon sheath into the normal abdominal aorta. IVC, and iliac artery of four adult dogs for 4 weeks to 12 weeks; 8 stents (10 mm in diameter fully expanded and 20 mm in length) in the abnormal aorta, 7 stents (12 mm/20 mm) in the IVC, and 5 stents (8 mm/20 mm) in the iliac artery. All but two stents showed no migration, and one complete occlusion occurred in right iliac artery of a dog. Histologically, stents wires were covered by neo-intimal proliferation. The side branches of the main vessels remained patent, even stent wires across their orifices. These metallic stents may be used as an endovascular graft material in the nonsurgical treatment of several forms of vascular disease.

  17. Factors leading to tracheobronchial self-expandable metallic stent fracture.

    Science.gov (United States)

    Chung, Fu-Tsai; Lin, Shu-Min; Chen, Hao-Cheng; Chou, Chun-Liang; Yu, Chih-Teng; Liu, Chien-Ying; Wang, Chun-Hua; Lin, Horng-Chyuan; Huang, Chien-Da; Kuo, Han-Pin

    2008-11-01

    This retrospective study was to determine factors that contribute to self-expandable metallic stent fracture in patients with tracheobronchial disease. From 2001 to 2006, 139 patients (age, 62.1 +/- 15.4 years; range, 23-87 years) with benign (n = 62) and malignant (n = 77) tracheobronchial disease received 192 Ultraflex (Boston Scientific, Natick, Mass) self-expandable metallic stents (98 in patients with benign disease and 94 in patients with malignant disease). Seventeen fractured self-expandable metallic stents were found; the incidence was 12.2% (17/139 patients) among patients with tracheobronchial disease. Tortuous airway (odds ratio, 4.06; 95% confidence interval, 1.04-18.34; P = .04) independently predicted self-expandable metallic stent fracture. Most self-expandable metallic stent fractures (64.7%, 11/17) were detected 500 to 1000 days after self-expandable metallic stent implantation. Clinical presentations for patients with fractured self-expandable metallic stents included dyspnea exacerbation (70.6%, 12/17) and cough (23.5%, 4/17). Self-expandable metallic stent fracture is not uncommon in patients with tracheobronchial disease. Tortuous airway is an independent predictor for it. Although management of the fractured self-expandable metallic stent in our study was feasible and safe, self-expandable metallic stents should be restricted to a more select population.

  18. Combined-stent covered technique and single covered stent technique for transjugular intrahepatic porto-systemic shunt: a prospective randomized controlled study

    International Nuclear Information System (INIS)

    Wang Changming; Li Xuan; Fu Jun; Lu Xianjun; Luan Jingyuan; Li Tianrun; Zhao Jun; Dong Guoxiang

    2014-01-01

    Objective: To compare the technique of combined stents with that of single stent-graft for the construction of transjugular intrahepatic porto-systemic shunt (TIPS) and to discuss their clinical outcomes. Methods: During the period from April 2011 to Dec. 2012, a total of 30 patients with upper gastrointestinal bleeding due to portal hypertension were admitted to the hospital. TIPS procedure was carried out in all the 30 patients. The patients were randomly allocated into either combined-stent group (n=17) or stent-graft group (control group, n=13) on the basis of a computer-generated randomization sequence. The PSC quality control, the patency rate of portal vein branches and the shunts, the incidence of encephalopathy and the survival rate of the two groups were documented and analyzed. Results: Technical success rate was 100%. After the treatment, in both groups the PSG became significantly lower than the PSG determined before the treatment (P<0.000). According to quality control chart, the of combined stents was superior to stent-graft technique in effectively controlling PSG. Five days after TIPS, the ammonia level in the combined- stent group was significantly decreased (P=0.029), while in the control group the ammonia level showed no significant changes (P=0.065). One patient died shortly after TIPS. The median follow- up time was 181 days. During the follow-up period death occurred in 3 cases in each group. The difference in the survival rate between the two groups was no significant (P=0.906). Of the three patients who developed encephalopathy, two were in the combined-stent group and one was in the control group. After medication the symptoms of encephalopathy were relieved. The patency rate of the shunts was 100% and the re-bleeding rate was 0% for both groups. The patency rate of portal vein branches was significantly higher in the combined-stent group than that in the control group (P=0.039). Conclusion: For the construction of TIPS, the technique of

  19. Delayed thrombosis or stenosis following enterprise-assisted stent-coiling: is it safe? Midterm results of the interstate collaboration of enterprise stent coiling.

    Science.gov (United States)

    Mocco, J; Fargen, Kyle M; Albuquerque, Felipe C; Bendok, Bernard R; Boulos, Alan S; Carpenter, Jeffrey S; Fiorella, David J; Hoh, Brian L; Howington, Jay U; Liebman, Kenneth M; Natarajan, Sabareesh K; Rai, Ansaar T; Rodriguez-Mercado, Rafael; Siddiqui, Adnan H; Snyder, Kenneth V; Veznedaroglu, Erol; Hopkins, L Nelson; Levy, Elad I

    2011-10-01

    Stent-assisted coiling of intracranial aneurysms with self-expanding stents has widened the applicability of neuroendovascular therapies to those aneurysms previously considered "uncoilable" because of poor morphology. The Enterprise Vascular Reconstruction Device and Delivery System (Cordis) has demonstrated promising initial short-term results. However, the rates of delayed in-stent stenosis or thrombosis are not known. To report midterm results of the Enterprise stent system. A 10-center registry was created to provide a large volume of data on the safety and efficacy of the Enterprise stent system. Pooled data were compiled for consecutive patients undergoing Enterprise stent-assisted coiling at each institution. Available follow-up data were evaluated for the incidence of in-stent stenosis, thrombosis, and aneurysm occlusion. In total, 213 patients (176 females) with 219 aneurysms were treated with the Enterprise stent. One hundred ten patients had undergone delayed angiography (≥ 30 days from stent placement, mean follow-up 174.6 days). Forty percent of patients demonstrated total occlusion with 88% having ≥ 90% aneurysm occlusion. Six percent of patients had delayed (>30 days) angiographic findings, of which 3% demonstrated significant (≥ 50%) in-stent stenosis or occlusion. Seven delayed thrombotic events occurred (3%), along with 2 additional immediate periprocedural events. All 7 delayed events were concomitant to cessation of double-antiplatelet therapy. Midterm occlusion rates are excellent, and stenosis and thrombosis rates are comparable to other available neurovascular stents. Interruption of antiplatelet therapy appears to be a factor in those developing delayed stenosis or thrombosis.

  20. Self-Expanding Nitinol Renal Artery Stents: Comparison of Safety and Efficacy of Bare Versus Polyzene-F Nanocoated Stents in a Porcine Model

    International Nuclear Information System (INIS)

    Kurz, P.; Stampfl, U.; Christoph, P.; Henn, C.; Satzl, S.; Radeleff, B.; Berger, I.; Richter, G. M.

    2011-01-01

    Objective: To investigate the safety and efficacy of a Polyzene-F nanocoat on new low-profile self-expandable nitinol stents in minipig renal arteries. Materials and Methods: Ten bare nitinol stents (BNS) and 10 stents coated with a 50 nm-thin Polyzene-F coating were randomly implanted into renal arteries of 10 minipigs (4- and 12-week follow-up, 5 animals/group). Thrombogenicity, on-stent surface endothelialization, vessel wall injury, late in-stent stenosis, and peristrut vessel wall inflammation were determined by quantitative angiography and postmortem histomorphometry. Results: In 6 of 10 BNS, >50% stenosis was found, but no stenosis was found in stents with a nanothin Polyzene-F coating. Histomorphometry showed a statistically significant (p < 0.05) different average maximum luminal loss of 55.16% ± 8.43% at 12 weeks in BNS versus 39.77% ± 7.41% in stents with a nanothin Polyzene-F coating. Stents with a nanothin Polyzene-F coating had a significantly (p < 0.05) lower inflammation score after 12 weeks, 1.31 ± 1.17 versus 2.17 ± 0.85 in BNS. The results for vessel wall injury (0.6 ± 0.58 for Polyzene-F-coated stents; 0.72 ± 0.98 for BNS) and re-endothelialization, (1.16 ± 0.43 and 1.23 ± 0.54, respectively) were not statistically significant at 12-week follow-up. No thrombus deposition was observed on the stents at either follow-up time point. Conclusion: Nitinol stents with a nanothin Polyzene-F coating successfully decreased in-stent stenosis and vessel wall inflammation compared with BNS. Endothelialization and vessel wall injury were found to be equal. These studies warrant long-term pig studies (≥120 days) because 12 weeks may not be sufficient time for complete healing; thereafter, human studies may be warranted.

  1. Stent placement for tracheal stenosis in patients with esophageal cancer

    International Nuclear Information System (INIS)

    Takagi, Keigo; Hata, Yoshinobu; Sasamoto, Shuichi; Takahashi, Shoji; Sato, Fumitomo; Tamaki, Kazuyoshi; Goto, Hidenori; Yuasa, Rena

    2011-01-01

    Tracheal invasion including tracheal bifurcation due to esophageal cancer can sometimes cause serious complications of the airway, but such cases sometimes improve quickly following chemoradiation treatment. The absolute indications for stent replacement in the airway for this disorder and the optimal choice of stent are herein discussed. Between 1992 and 2010, 28 patients with airway stenosis, including 7 patients with esophago-tracheal fistula, were treated by placement of various stents; namely, 12 patients received Dumon stents, 3 patients had Dynamic stents, 10 patients were given Ultraflex stents, while 3 other patients were treated without the use of stents. Severe dyspnea in the supine position was observed, which mainly originated from invasion to the membranous portion of the trachea. Airway patency was maintained after stent replacement, although the median survival time of such cases was only 4 months. Three patients with severe dyspnea who could lie in a supine position recovered after undergoing chemoradiation treatment without stent replacement. No cases of stent removal were observed after chemoradiation treatment. Chemoradiation treatment for esophageal cancer was found to be effective for the management of airway disturbances, and thus the absolute indications for stent replacement are restricted to patients who cannot lie in a supine position due to severe impairment of ventilation during radiation therapy, as well as patients presenting with tracheobroncho-esophageal fistula. Concerning stent selection, a metal stent should be the first choice for tracheal stenosis due to its ease of insertion, because there is no substantial difference between silicone and metal stents regarding the treatment of tracheal stenosis. However, it is important to note that a silicone Y stent is useful for the treatment of tracheal bifurcation. (author)

  2. Fully-covered metal stents with endoscopic suturing vs. partially-covered metal stents for benign upper gastrointestinal diseases: a comparative study

    Science.gov (United States)

    Ngamruengphong, Saowanee; Sharaiha, Reem; Sethi, Amrita; Siddiqui, Ali; DiMaio, Christopher J.; Gonzalez, Susana; Rogart, Jason; Jagroop, Sophia; Widmer, Jessica; Im, Jennifer; Hasan, Raza Abbas; Laique, Sobia; Gonda, Tamas; Poneros, John; Desai, Amit; Wong, Katherine; Villgran, Vipin; Brewer Gutierrez, Olaya; Bukhari, Majidah; Chen, Yen-I; Hernaez, Ruben; Hanada, Yuri; Sanaei, Omid; Agarwal, Amol; Kalloo, Anthony N.; Kumbhari, Vivek; Singh, Vikesh; Khashab, Mouen A.

    2018-01-01

    Background and study aims  Self-expandable metallic stents (SEMS) have been increasingly used in benign conditions (e. g. strictures, fistulas, leaks, and perforations). Fully covered SEMS (FSEMS) were introduced to avoid undesirable consequences of partially covered SEMS (PSEMS), but come with higher risk of stent migration. Endoscopic suturing (ES) for stent fixation has been shown to reduce migration of FSEMS. Our aim was to compare the outcomes of FSEMS with ES (FS/ES) versus PSEMS in patients with benign upper gastrointestinal conditions. Patients and methods  We retrospectively identified all patients who underwent stent placement for benign gastrointestinal conditions at seven US tertiary-care centers. Patients were divided into two groups: FSEMS with ES (FS/ES group) and PSEMS (PSEMS group). Clinical outcomes between the two groups were compared. Results  A total of 74 (FS/ES 46, PSEMS 28) patients were included. On multivariable analysis, there was no significant difference in rate of stent migration between FS/ES (43 %) and PSEMS (15 %) (adjusted odds ratio 0.56; 95 % CI 0.15 – 2.00). Clinical success was similar [68 % vs. 64 %; P  = 0.81]. Rate of adverse events (AEs) was higher in PSEMS group [13 (46 %) vs. 10 (21 %); P  = 0.03). Difficult stent removal was higher in the PSEMS group (n = 5;17 %) vs. 0 % in the FS/ES group; P  = 0.005. Conclusions  The proportion of stent migration of FS/ES and PSEMS are similar. Rates of other stent-related AEs were higher in the PSEMS group. PSEMS was associated with tissue ingrowth or overgrowth leading to difficult stent removal, and secondary stricture formation. Thus, FSEMS with ES for stent fixation may be the preferred modality over PSEMS for the treatment of benign upper gastrointestinal conditions. PMID:29404384

  3. Migrated esophageal stent posing a challenge for ventilation

    Directory of Open Access Journals (Sweden)

    Nita D'souza

    2017-01-01

    Full Text Available Self-expandable esophageal stents are being commonly used for palliative treatment in advanced esophageal cancer patients to relieve dysphagia, prevent tracheoesophageal fistula, and facilitate symptomatic betterment. The modern covered stents reduce the ingrowth of the tumor but have seen an increase in the incidence of stent migrations. We report a rather complicated presentation of an esophageal stent for esophageal dilatation and a challenging management of a difficult tracheostomy.

  4. Temporary stenting and retrieval of the self-expandable, intracranial stent in acute middle cerebral artery occlusion

    Energy Technology Data Exchange (ETDEWEB)

    Suh, Sang Hyun; Chung, Tae-Sub [Yonsei University College of Medicine, Department of Radiology, Gangnam Severance Hospital, Seoul (Korea); Lee, Kyung-Yul [Yonsei University College of Medicine, Department of Neurology, Gangnam Severance Hospital, Seoul (Korea); Hong, Chang Ki; Kim, Chang-Hyun [Yonsei University College of Medicine, Department of Neurosurgery, Gangnam Severance Hospital, Seoul (Korea); Kim, Byung Moon; Kim, Dong Ik [Yonsei University College of Medicine, Department of Radiology, Seoul (Korea)

    2009-08-15

    We describe our experience in which a retrievable Enterprise stent was used as a temporary recanalization and embolectomy device in an acute middle cerebral artery (MCA) occlusion after urgent stenting for ipsilateral carotid artery stenosis. (orig.)

  5. Differences in Endothelial Injury After Balloon Angioplasty, Insertion of Balloon-Expanded Stents or Release of Self-Expanding Stents: An Electron Microscopic Experimental Study

    International Nuclear Information System (INIS)

    Harnek, Jan; Zoucas, Evita; Carlemalm, Erik; Cwikiel, Wojciech

    1999-01-01

    Purpose: To evaluate which of six different commonly available stents inserted into an artery without percutaneous transluminal angioplasty (PTA) causes the least endothelial damage. To compare the degree of endothelial injury after insertion of such a stent with injury caused by PTA. Methods: Twelve healthy pigs were used in the experiments. In the first part of the study six different types of stents were inserted into the common iliac arteries. In the second part of the study self-expanding stents with large spaces between the wires were used. PTA was performed in the contralateral iliac artery. The pigs were killed immediately after the procedure and resected specimens examined after fixation, using scanning electron microscopy. Results: All procedures but two were accomplished successfully. More endothelium was preserved after insertion of self-expanding stents with large spaces between the wires, compared with stents with small spaces and balloon-expanded stents. After insertion of self-expanding stents with large spaces, 50.1% ± 16.4% of the endothelium remained intact, compared with only 5.6% ± 7.7% after PTA. The difference was statistically significant (p < 0.001). Conclusion: Self-expanding stents with large spaces between the wires, inserted without PTA, cause less damage to the endothelium than other stents and significantly less damage than PTA

  6. Impact of stent diameter and length on in-stent restenosis after DES vs BMS implantation in patients needing large coronary stents-A clinical and health-economic evaluation.

    Science.gov (United States)

    Zbinden, Rainer; von Felten, Stefanie; Wein, Bastian; Tueller, David; Kurz, David J; Reho, Ivano; Galatius, Soren; Alber, Hannes; Conen, David; Pfisterer, Matthias; Kaiser, Christoph; Eberli, Franz R

    2017-02-01

    The British National Institute of Clinical Excellence (NICE) guidelines recommend to use drug-eluting stents (DES) instead of bare-metal stents (BMS) only in lesions >15 mm in length or in vessels stent length and stent diameter on in-stent restenosis (ISR) in the BASKET-PROVE study population and evaluated the cost-effectiveness of DES compared to BMS. The BASKET-PROVE trial compared DES vs BMS in large coronary arteries (≥3 mm). We calculated incremental cost-effectiveness ratios (ICERs) and cost-effectiveness acceptability curves with regard to quality-adjusted life years (QALYs) gained and target lesion revascularizations (TLRs) avoided. A total of 2278 patients were included in the analysis. A total of 74 ISR in 63 patients were observed. In-stent restenosis was significantly more frequent in segments treated with a BMS compared to segments treated with a DES (5.4% vs 0.76%; Pstent length >15 mm and ≤15 mm, respectively. With the use of DES in short lesions, there was only a minimal gain of 0.005 in QALYs. At a threshold of 10 000 CHF per TLR avoided, DES had a high probability of being cost-effective. In the BASKET-PROVE study population, the strongest predictor of ISR is the use of a BMS, even in patients in need of stents ≥3.0 mm and ≤15 mm lesion length and DES were cost-effective. This should prompt the NICE to reevaluate its recommendation to use DES instead of BMS only in vessels 15 mm length. © 2016 John Wiley & Sons Ltd.

  7. Primary stent placement for recanalization of iliac artery occlusions: Using a self-expanding spiral stent

    International Nuclear Information System (INIS)

    Kim, Jae-Kyu; Kim, Yun-Hyeon; Chung, Sang-Yeung; Kang, Heoung-Keun

    1999-01-01

    Purpose: To report the clinical results for recanalizations of an occluded iliac artery by a self-expanding spiral stent.Methods: We attempted to recanalize 36 iliac artery occlusions in 34 patients [33 men, 1 woman, aged 51-75 years (average 61.6 years)]. The average lesion length was 6.92 cm (range 1-14 cm). The patients's chief complaints were intermittent claudication and resting pain. Fontaine classification was assigned before and after the procedure. Technical and clinical success were also analyzed.Results: Forty-five stents were successfully deployed in 34 patients. All 36 lesions (13 in the external iliac artery, 12 in the common iliac artery, and 11 in both) were patently recanalized on angiography. The follow-up period ranged from 6 months to 36 months (mean 11.9 months). Fourteen stents (39%) with incomplete expansion were dilated with a balloon catheter. Good technical (100%) and clinical (94%) results were obtained. The only complication was one hematoma at the puncture site. Reocclusions were noted in two lesions (5%) at 1 week and 15 months, respectively.Conclusion: A self-expanding spiral stent is a safe and effective device for recanalization of an iliac artery occlusion as the primary stent without any previous intervention.

  8. Bronchoscopic guidance of endovascular stenting limits airway compression.

    Science.gov (United States)

    Ebrahim, Mohammad; Hagood, James; Moore, John; El-Said, Howaida

    2015-04-01

    Bronchial compression as a result of pulmonary artery and aortic arch stenting may cause significant respiratory distress. We set out to limit airway narrowing by endovascular stenting, by using simultaneous flexible bronchoscopy and graduated balloon stent dilatation, or balloon angioplasty to determine maximum safe stent diameter. Between August 2010 and August 2013, patients with suspected airway compression by adjacent vascular structures, underwent CT or a 3D rotational angiogram to evaluate the relationship between the airway and the blood vessels. If these studies showed close proximity of the stenosed vessel and the airway, simultaneous bronchoscopy and graduated stent re-dilation or graduated balloon angioplasty were performed. Five simultaneous bronchoscopy and interventional catheterization procedures were performed in four patients. Median age/weight was 33 (range 9-49) months and 14 (range 7.6-24) kg, respectively. Three had hypoplastic left heart syndrome, and one had coarctation of the aorta (CoA). All had confirmed or suspected left main stem bronchial compression. In three procedures, serial balloon dilatation of a previously placed stent in the CoA was performed and bronchoscopy was used to determine the safest largest diameter. In the other two procedures, balloon testing with simultaneous bronchoscopy was performed to determine the stent size that would limit compression of the adjacent airway. In all cases, simultaneous bronchoscopy allowed selection of an ideal caliber of the stent that optimized vessel diameter while minimizing compression of the adjacent airway. In cases at risk for airway compromise, flexible bronchoscopy is a useful tool to guide endovascular stenting. Maximum safe stent diameter can be determined without risking catastrophic airway compression. © 2014 Wiley Periodicals, Inc.

  9. Radiologic placement of metallic esophageal stents: preliminary experience

    International Nuclear Information System (INIS)

    Good, S.; Asch, M.R.; Jaffer, N.; Casson, A.G.

    1997-01-01

    To assess the usefulness of covered, self expanding metallic stents for alleviating stricture associated with malignant esophageal lesions. Patients and methods: Self-expanding metallic stents were placed in 10 patients with dysphagia related to stricture caused by malignant esophageal lesions. The stents were placed fluoroscopically with local anesthesia, and patency of the esophageal lumen was assessed by barium study after the procedure. The patients were then followed clinically. Results: In all 10 cases patency of the lumen was renewed after stent placement. After the procedure 9 of the patients could tolerate a normal or near-normal diet; in the other patient esophageal perforation occurred, and clinical deterioration prevented oral intake of food. In one patient, 2 stents were needed because of the length of the stricture. Two patients experienced reflux after placement of the stent across the gastro-esophageal junction. Another patient had asymptomatic aspiration after stent placement in the proximal esophagus. In 2 patients, symptoms associated with tracheoesophageal fistula were relieved after placement of the stents. Six of the 10 patients died; mean survival after the procedure was 12 (range 1 to 56) weeks. The other 4 patients were alive at the time of writing, having survived for a mean of 7.5 (range 2 to 13) weeks; all of these patients tolerated a near-normal diet. Conclusions: The placement of covered, self-expanding metallic stents is a quick, effective method of palliating dysphagia related to stricture caused by malignant esophageal lesions. (author)

  10. French experience of silicone tracheobronchial stenting in children.

    Science.gov (United States)

    Fayon, Michael; Donato, Lionel; de Blic, Jacques; Labbé, André; Becmeur, François; Mely, Laurent; Dutau, Hervé

    2005-01-01

    Silicone stents were inserted into the trachea or left main-stem bronchus in 14 children aged 2-69 months (median, 7 months). Indications were as follows: tracheomalacia or airway kinking (7 cases), vascular compression (5 cases), and surgically corrected congenital tracheal stenoses (2 cases). The best results were obtained in tracheomalacia. Overall, 6 cases out of 14 (43%) were considered successful, with a stent placement duration of 3-15 months (median, 7 months). Two cases were considered a technical success, although they were clinical failures. Five cases were considered failures primarily due to stent migration. A retrospective analysis of failures suggests that most of these could have been avoided by the use of larger stents. One patient died of stent obstruction. No wall erosion was observed, and the development of granulation tissue was infrequent. Endoscopic removal of the prostheses was uneventful. The biocompatibility of silicone stents appears to be better than what is reported for metal ones, although the stability of the former is less satisfactory. The present study shows the feasibility of silicone stent placement in infants. These stents should be considered as a possible therapeutic option in certain types of childhood airway disorders, although further studies are required.

  11. Coated stents to prevent restenosis in coronary heart disease

    Directory of Open Access Journals (Sweden)

    Hagen, Anja

    2005-11-01

    Full Text Available Background: In-stent-restenosis (ISR is considered to be an essential limiting factor of stenting in coronary heart disease (CHD. The development of coated stents has raised expectations on substantial lowering restenosis after stenting with decreasing the rate of restenosis and a reduction in the rate of clinical events. Objectives: The present analysis addresses the questions on medical effectiveness and cost-effectiveness of the use of various coated stent types in CHD. Methods: The literature was searched in December 2004 in the most relevant medical and economic databases. The medical evaluation was conducted on the basis of published RCT. The data from the studies regarding various angiographic, sonographic and clinical endpoints were checked for methodical quality and summarised in meta-analyses. Within the scope of economic evaluation the primary studies were analysed and modelling was performed, applying clinical effect estimates from the meta-analyses of the medical evaluation and current estimates of German costs. Results: Medical evaluation: Ten different stenttypes were used in the included 26 RCT. The results for heparin, silicon-carbide, carbon and PTFE coated stenttypes could not reveal any significant differences between the medical effectiveness of coated and uncoated stents. The application of sirolimus, paclitaxel, everolimus and 7-hexanoyltaxol eluting stents showed a significant lower restenosis at 6-9 months with decrease in the rate of restenosis for polymer-based sirolimus, paclitaxel and 7-hexanoyltaxol eluting stents. In contrast, the use of gold-coated and actinomycin-D eluting stents was associated with a significantly higher restenosis. The polymer-based sirolimus and paclitaxel eluting stents also showed a significant and considerable reduction in the rate of repeated percutaneous revascularisations at 6-12 months (3.5% vs. 19.7%; p<0.0001, RR=0.19 [95%CI: 0.11; 0.33] and 3.5% vs. 12.2%; p<0.0001, RR=0.30 [95%CI: 0

  12. Endoscopic stenting for hilar cholangiocarcinoma: efficacy of unilateral and bilateral placement of plastic and metal stents in a retrospective review of 480 patients

    Directory of Open Access Journals (Sweden)

    Liberato Manuel José

    2012-08-01

    Full Text Available Abstract Background Endoscopic biliary drainage of hilar cholangiocarcinoma is controversial with respect to the optimal types of stents and the extent of drainage. This study evaluated endoscopic palliation in patients with hilar cholangiocarcinoma using self-expandable metallic stents (SEMS and plastic stents (PS.We also compared unilateral and bilateral stent placement according to the Bismuth classification. Methods Data on 480 patients receiving endoscopic biliary drainage for hilar cholangiocarcinoma between September 1995 and December 2010 were retrospectively reviewed to evaluate the following outcome parameters: technical success (TS, functional success (FS, early and late complications, stent patency and survival. Patients were followed from stent insertion until death or stent occlusion. Patients were divided into 3 groups according to the Bismuth classification (Group 1, type I; Group 2, type II; Group 3, type > III. Results The initial stent insertion was successful in 450 (93.8% patients. TS was achieved in 204 (88.3% patients treated with PS and in 246 (98.8% patients palliated with SEMS (p P P  Conclusions SEMS insertion for the palliation of hilar cholangiocarcinoma offers higher technical and clinical success rates in the ITT analysis as well as lower complication rates and a superior cumulative stent patency when compared with PS placement in all Bismuth classifications. The cumulative patency of bilateral SEMS or PS stents was significantly higher than that of unilateral SEMS or PS stents, with lower occlusion rates in Bismuth II patients.

  13. Computational micromechanics of bioabsorbable magnesium stents.

    Science.gov (United States)

    Grogan, J A; Leen, S B; McHugh, P E

    2014-06-01

    Magnesium alloys are a promising candidate material for an emerging generation of absorbable metal stents. Due to its hexagonal-close-packed lattice structure and tendency to undergo twinning, the deformation behaviour of magnesium is quite different to that of conventional stent materials, such as stainless steel 316L and cobalt chromium L605. In particular, magnesium exhibits asymmetric plastic behaviour (i.e. different yield behaviours in tension and compression) and has lower ductility than these conventional alloys. In the on-going development of absorbable metal stents it is important to assess how the unique behaviour of magnesium affects device performance. The mechanical behaviour of magnesium stent struts is investigated in this study using computational micromechanics, based on finite element analysis and crystal plasticity theory. The plastic deformation in tension and bending of textured and non-textured magnesium stent struts with different numbers of grains through the strut dimension is investigated. It is predicted that, unlike 316L and L605, the failure risk and load bearing capacity of magnesium stent struts during expansion is not strongly affected by the number of grains across the strut dimensions; however texturing, which may be introduced and controlled in the manufacturing process, is predicted to have a significant influence on these measures of strut performance. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Malignant duodenal obstructions: palliative treatment with covered expandable nitinol stent

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyun Chul; Jung, Gyoo Sik; Lee, Sang Hee; Kim, Sung Min; Oh, Kyung Seung; Huh, Jin Do; Cho, Young Duk [College of Medicine, Kosin Univ, Pusan (Korea, Republic of); Song, Ho Young [College of Medicine, Ulsan Univ., Seoul (Korea, Republic of)

    2002-04-01

    To evaluate the feasibility and clinical effectiveness of using a polyurethane-covered expandable nitinol stent in the palliative treatment of malignant duodenal obstruction. Under fluoroscopic guidance, a polyurethane-covered expandable nitinol stent was placed in 12 consecutive patients with malignant duodenal obstructions. All presented with severe nausea and recurrent vomiting. The underlying causes of obstruction were duodenal carcinoma (n=4), pancreatic carcinoma (n=4), gall bladder carcinoma (n=2), distal CBD carcinoma (n=1), and uterine cervical carcinoma (n=1). The sites of obstruction were part I (n=1), part II (n=8), and III (n=3). Due to pre-existing jaundice, eight patients with part II obstructions underwent biliary decompression prior to stent placement. An introducer sheath with a 6-mm outer diameter and stents 16 mm in diameter were employed, and to place the stent, and after-loading technique was used. Stent placement was technically successful in ten patients, and no procedural complications occuured. In one of two patients in whom there was technical failure, and in whom the obstructions were located in part III, the stent was placed transgastrically. Stent migration occurred in one patient four days after the procedure, and treatment involved the palcement of a second, uncovered, nitinol stent. After stent placement, symptoms improved in all patients. During follow-up, obstructive symptoms due to stent stenosis (n=1), colonic obstruction (n=1), and multiple small bowel obstruction (n=1) recurred in three patients. Two of these were treated by placing additional stents in the duodenum and colon, respectively. One of the eight patients in whom a stent was placed in the second portion of the duodenum developed jaundice. The patients died a mean 14 (median, 9) weeks after stent placement. The placement of a polyurethane-covered expandable nitinol stent seems to be technically feasible, safe and effective for the palliative treatment of malignant

  15. Flow Velocities After Carotid Artery Stenting: Impact of Stent Design. A Fluid Dynamics Study in a Carotid Artery Model with Laser Doppler Anemometry

    International Nuclear Information System (INIS)

    Greil, Oliver; Kleinschmidt, Thomas; Weiss, Wolfgang; Wolf, Oliver; Heider, Peter; Schaffner, Silvio; Gianotti, Marc; Schmid, Thomas; Liepsch, Dieter; Berger, Hermann

    2005-01-01

    Purpose. To study the influence of a newly developed membrane stent design on flow patterns in a physiologic carotid artery model. Methods. Three different stents were positioned in silicone models of the carotid artery: a stainless steel stent (Wall-stent), a nitinol stent (SelfX), and a nitinol stent with a semipermeable membrane (MembraX). To increase the contact area of the membrane with the vessel wall, another MembranX model was modified at the outflow tract. The membrane consists of a biocompatible silicone-polyurethane copolymer (Elast-Eon) with a pore size of 100 μm. All stents were deployed across the bifurcation and the external carotid artery origin. Flow velocity measurements were performed with laser Doppler anemometry (LDA), using pulsatile flow conditions (Re = 220; flow 0.39 l/min; flow rate ratio ICA:ECA = 70:30) in hemodynamically relevant cross-sections. The hemodynamic changes were analyzed by comparing velocity fluctuations of corresponding flow profiles. Results. The flow rate ratio ICA:ECA shifted significantly from 70/30 to 73.9/26.1 in the MembraX and remained nearly unchanged in the SelfX and Wallstent. There were no changes in the flow patterns at the inflow proximal to the stents. In the stent no relevant changes were found in the SelfX. In the Wallstent the separation zone shifted from the orifice of the ICA to the distal end of the stent. Four millimeters distal to the SelfX and the Wallstent the flow profile returned to normal. In the MembraX an increase in the central slipstreams was found with creation of a flow separation distal to the stent. With a modification of the membrane this flow separation vanished. In the ECA flow disturbances were seen at the inner wall distal to the stent struts in the SelfX and the Wallstent. With the MembraX a calming of flow could be observed in the ECA with a slight loss of flow volume. Conclusions. Stent placement across the carotid artery bifurcation induces alterations of the physiologic flow

  16. Physical properties of a new type of self-expandable nitinol stent

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sang Soo [Seoul Health College, Seoul (Korea, Republic of); Kim, Tae Hyung; Song, Sang Woo; Kang, Seong Gwon; Huh, Soo Jin; Song, Ho Young [Ulsan Univ. College of Medicine, Seoul (Korea, Republic of); Kim, Eun Sang [Stentech, Inc., Seoul (Korea, Republic of); Kim, Cheol Saeng [Solco Surgical Instruments Co., Ltd, Seoul (Korea, Republic of)

    1999-08-01

    To study the new physical properties including hoop strength and flexibility of a newly developed nitinol stent. The new stent was made of a single nitinol wire 0.15 - 0.25 mm in diameter. This was wound around a cylindrical metallic jig with a constant angle to the longitudinal direction, and stents which winding were constructed. Hoop strength of the stents was measured with a spring gauge and compared with that of Wallstent and Hanaro stents. The flexibility of the new stent was evaluated on the basis of changes in stent diameter when bent in the direction of 180 deg Hoop strength of the new nitinol stent was proportional to 3.8 ({+-}0.3)-th power of the wire thickness. A greater number of wires on a lateral cut surface or a greater number of longitudinal windings also resulted in increased strength. However, the former caused an increase in total wire area and the latter resulted increased stent length when compressed. Hoop strength of the new nitinol stent was superior to that of Wallstent and Hanaro stents, and stent diameter did not decrease when the stent was bent in the direction of 180 degrees. Hoop strength of the new nitinol stent was most significantly affected by wire thickness. The stent was very flexible and thus seemed suitable for an angled lumen.

  17. Stent implantation as a palliative means of treatment in inoperable bronchial tumors. Preliminary experience with an endoscopically implanted stent

    Energy Technology Data Exchange (ETDEWEB)

    Beck, A; Nanko, N; Schildge, J; Hasse, J

    1989-08-01

    Imminent asphyxia due to tracheal or bronchial compression by inoperable tumors in the mediastinum and the central bronchi is serious, particularly if alternative treatments, i.e., radiation or chemotherapy, have been exhausted. For that reason, stents of different diameters and lengths were developed that could be dilated. With the patient under general anesthesia these stents can be introduced into the stenotic bronchus or trachea through a rigid bronchoscope. The appropriate stent is mounted on a 3-mm balloon catheter, which is inflated after the stent is in the correct position. Positioning is done under direct bronchoscopic and fluoroscopic control. After deflation of the balloon, the stent maintains its cross-sectional shape and keeps the airway open. The first clinical application was in a 53-year-old patient with end-stage small-cell carcinoma. The patient had had a relapse after combined chemo- and radiotherapy and had severe stridor. Stent insertion led to a significant relief of symptoms. The second patient, a 53-year-old woman who suffered from collapse of the bronchus caused by a radionecrosis, was treated by the same method. Nine months later, ventilation is excellent in the left lung, and the patient can tolerate the stent without any clinical symptoms. A 69-year-old woman suffered from a tracheal carcinoma with severe tracheal stenosis. It was possible to maintain the stability of the collapsed tracheal wall by insertion of a trachial stent. This new technique can provide good palliative treatment and is sometimes even the main therapy in such cases. (orig.).

  18. Flow Characteristics Near to Stent Strut Configurations on Femoropopliteal Artery

    Science.gov (United States)

    Paisal, Muhammad Sufyan Amir; Fadhil Syed Adnan, Syed; Taib, Ishkrizat; Ismail, Al Emran; Kamil Abdullah, Mohammad; Nordin, Normayati; Seri, Suzairin Md; Darlis, Nofrizalidris

    2017-08-01

    Femoropopiteal artery stenting is a common procedure suggested by medical expert especially for patient who is diagnosed with severe stenosis. Many researchers reported that the growth of stenosis is significantly related to the geometry of stent strut configuration. The different shapes of stent geometry are presenting the different flow pattern and re-circulation in stented femoropopliteal artery. The blood flow characteristics near to the stent geometry are predicted for the possibility of thrombosis and atherosclerosis to be formed as well as increase the growth of stenosis. Thus, this study aims to determine the flow characteristic near to stent strut configuration based on different hemodynamic parameters. Three dimensional models of stent and simplified femoropopliteal artery are modelled using computer aided design (CAD) software. Three different models of stent shapes; hexagon, circle and rectangle are simulated using computational fluid dynamic (CFD) method. Then, parametric study is implemented to predict the performance of stent due to hemodynamic differences. The hemodynamic parameters considered are pressure, velocity, low wall shear stress (WSSlow) and wall shear stress (WSS). From the observation, flow re-circulation has been formed for all simulated stent models which the proximal region shown the severe vortices. However, rectangular shape of stent strut (Type P3) shows the lowest WSSlow and the highest WSS between the range of 4 dyne/cm2 and 70 dyne/cm2. Stent Type P3 also shows the best hemodynamic stent performance as compare to others. In conclusion, Type P3 has a favourable result in hemodynamic stent performance that predicted less probability of thrombosis and atherosclerosis to be formed as well as reduces the growth of restenosis.

  19. Angioplasty and stent placement - peripheral arteries

    Science.gov (United States)

    ... medlineplus.gov/ency/article/007393.htm Angioplasty and stent placement - peripheral arteries To use the sharing features ... inside the arteries and block blood flow. A stent is a small, metal mesh tube that keeps ...

  20. A sirolimus-eluting bioabsorbable polymer-coated stent (MiStent) versus an everolimus-eluting durable polymer stent (Xience) after percutaneous coronary intervention (DESSOLVE III): a randomised, single-blind, multicentre, non-inferiority, phase 3 trial

    NARCIS (Netherlands)

    de Winter, Robbert J.; Katagiri, Yuki; Asano, Taku; Milewski, Krzysztof P.; Lurz, Philipp; Buszman, Pawel; Jessurun, Gillian A. J.; Koch, Karel T.; Troquay, Roland P. T.; Hamer, Bas J. B.; Ophuis, Ton Oude; Wöhrle, Jochen; Wyderka, Rafał; Cayla, Guillaume; Hofma, Sjoerd H.; Levesque, Sébastien; Żurakowski, Aleksander; Fischer, Dieter; Kośmider, Maciej; Goube, Pascal; Arkenbout, E. Karin; Noutsias, Michel; Ferrari, Markus W.; Onuma, Yoshinobu; Wijns, William; Serruys, Patrick W.

    2018-01-01

    Background MiStent is a drug-eluting stent with a fully absorbable polymer coating containing and embedding a microcrystalline form of sirolimus into the vessel wall. It was developed to overcome the limitation of current durable polymer drug-eluting stents eluting amorphous sirolimus. The clinical

  1. Development of biodegradable magnesium alloy stents with coating

    Directory of Open Access Journals (Sweden)

    Lorenza Petrini

    2014-07-01

    Full Text Available Biodegradable stents are attracting the attention of many researchers in biomedical and materials research fields since they can absolve their specific function for the expected period of time and then gradually disappear. This feature allows avoiding the risk of long-term complications such as restenosis or mechanical instability of the device when the vessel grows in size in pediatric patients. Up to now biodegradable stents made of polymers or magnesium alloys have been proposed. However, both the solutions have limitations. The polymers have low mechanical properties, which lead to devices that cannot withstand the natural contraction of the blood vessel: the restenosis appears just after the implant, and can be ascribed to the compliance of the stent. The magnesium alloys have much higher mechanical properties, but they dissolve too fast in the human body. In this work we present some results of an ongoing study aiming to the development of biodegradable stents made of a magnesium alloy that is coated with a polymer having a high corrosion resistance. The mechanical action on the blood vessel is given by the magnesium stent for the desired period, being the stent protected against fast corrosion by the coating. The coating will dissolve in a longer term, thus delaying the exposition of the magnesium stent to the corrosive environment. We dealt with the problem exploiting the potentialities of a combined approach of experimental and computational methods (both standard and ad-hoc developed for designing magnesium alloy, coating and scaffold geometry from different points of views. Our study required the following steps: i selection of a Mg alloy suitable for stent production, having sufficient strength and elongation capability; ii computational optimization of the stent geometry to minimize stress and strain after stent deployment, improve scaffolding ability and corrosion resistance; iii development of a numerical model for studying stent

  2. Drug-eluting stents versus bare-metal stents for acute coronary syndrome

    DEFF Research Database (Denmark)

    Feinberg, Joshua; Nielsen, Emil Eik; Greenhalgh, Janette

    2017-01-01

    -EXPANDED, and BIOSIS from their inception to January 2017. We also searched two clinical trials registers, the European Medicines Agency and the US Food and Drug Administration databases, and pharmaceutical company websites. In addition, we searched the reference lists of review articles and relevant trials. SELECTION...... CRITERIA: Randomised clinical trials assessing the effects of drug-eluting stents versus bare-metal stents for acute coronary syndrome. We included trials irrespective of publication type, status, date, or language. DATA COLLECTION AND ANALYSIS: We followed our published protocol and the methodological...

  3. Fenestrated Stent Graft Repair of Abdominal Aortic Aneurysm: Hemodynamic Analysis of the Effect of Fenestrated Stents on the Renal Arteries

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Zhonghua; Chaichana, Thanapong [Curtin University of Technology, Perth (Australia)

    2010-02-15

    We wanted to investigate the hemodynamic effect of fenestrated stents on the renal arteries with using a fluid structure interaction method. Two representative patients who each had abdominal aortic aneurysm that was treated with fenestrated stent grafts were selected for the study. 3D realistic aorta models for the main artery branches and aneurysm were generated based on the multislice CT scans from two patients with different aortic geometries. The simulated fenestrated stents were designed and modelled based on the 3D intraluminal appearance, and these were placed inside the renal artery with an intra-aortic protrusion of 5.0-7.0 mm to reflect the actual patients' treatment. The stent wire thickness was simulated with a diameter of 0.4 mm and hemodynamic analysis was performed at different cardiac cycles. Our results showed that the effect of the fenestrated stent wires on the renal blood flow was minimal because the flow velocity was not significantly affected when compared to that calculated at pre-stent graft implantation, and this was despite the presence of recirculation patterns at the proximal part of the renal arteries. The wall pressure was found to be significantly decreased after fenestration, yet no significant change of the wall shear stress was noticed at post-fenestration, although the wall shear stress was shown to decrease slightly at the proximal aneurysm necks. Our analysis demonstrates that the hemodynamic effect of fenestrated renal stents on the renal arteries is insignificant. Further studies are needed to investigate the effect of different lengths of stent protrusion with variable stent thicknesses on the renal blood flow, and this is valuable for understanding the long-term outcomes of fenestrated repair.

  4. Fenestrated Stent Graft Repair of Abdominal Aortic Aneurysm: Hemodynamic Analysis of the Effect of Fenestrated Stents on the Renal Arteries

    International Nuclear Information System (INIS)

    Sun, Zhonghua; Chaichana, Thanapong

    2010-01-01

    We wanted to investigate the hemodynamic effect of fenestrated stents on the renal arteries with using a fluid structure interaction method. Two representative patients who each had abdominal aortic aneurysm that was treated with fenestrated stent grafts were selected for the study. 3D realistic aorta models for the main artery branches and aneurysm were generated based on the multislice CT scans from two patients with different aortic geometries. The simulated fenestrated stents were designed and modelled based on the 3D intraluminal appearance, and these were placed inside the renal artery with an intra-aortic protrusion of 5.0-7.0 mm to reflect the actual patients' treatment. The stent wire thickness was simulated with a diameter of 0.4 mm and hemodynamic analysis was performed at different cardiac cycles. Our results showed that the effect of the fenestrated stent wires on the renal blood flow was minimal because the flow velocity was not significantly affected when compared to that calculated at pre-stent graft implantation, and this was despite the presence of recirculation patterns at the proximal part of the renal arteries. The wall pressure was found to be significantly decreased after fenestration, yet no significant change of the wall shear stress was noticed at post-fenestration, although the wall shear stress was shown to decrease slightly at the proximal aneurysm necks. Our analysis demonstrates that the hemodynamic effect of fenestrated renal stents on the renal arteries is insignificant. Further studies are needed to investigate the effect of different lengths of stent protrusion with variable stent thicknesses on the renal blood flow, and this is valuable for understanding the long-term outcomes of fenestrated repair

  5. Drug-eluting stent thrombosis: results from the multicenter Spanish registry ESTROFA (Estudio ESpañol sobre TROmbosis de stents FArmacoactivos).

    Science.gov (United States)

    de la Torre-Hernández, José M; Alfonso, Fernando; Hernández, Felipe; Elizaga, Jaime; Sanmartin, Marcelo; Pinar, Eduardo; Lozano, Iñigo; Vazquez, Jose M; Botas, Javier; Perez de Prado, Armando; Hernández, Jose M; Sanchis, Juan; Nodar, Juan M Ruiz; Gomez-Jaume, Alfredo; Larman, Mariano; Diarte, Jose A; Rodríguez-Collado, Javier; Rumoroso, Jose R; Lopez-Minguez, Jose R; Mauri, Josepa

    2008-03-11

    This study sought to assess the incidence, predictors, and outcome of drug-eluting stent(DES) thrombosis in real-world clinical practice. The DES thromboses in randomized trials could not be comparable to those observed in clinical practice, frequently including off-label indications. We designed a large-scale, nonindustry-linked multicentered registry, with 20 centers in Spain. The participant centers provided follow-up data for their patients treated with DES, reporting a detailed standardized form in the event of any angiography-documented DES-associated thrombosis occurring. Of 23,500 patients treated with DES, definite stent thrombosis(ST) developed in 301: 24 acute, 125 subacute, and 152 late. Of the late, 62 occurred >1 year(very late ST). The cumulative incidence was 2% at 3 years. Antiplatelet treatment had been discontinued in 95 cases(31.6%). No differences in incidences were found among stent types. Independent predictors for subacute ST analyzed in a subgroup of 14,120 cases were diabetes, renal failure, acute coronary syndrome, ST-segment elevation myocardial infarction, stent length, and left anterior descending artery stenting, and for late ST were ST-segment elevation myocardial infarction, stenting in left anterior descending artery, and stent length. Mortality at 1-year follow-up was 16% and ST recurrence 4.6%. Older age, left ventricular ejection fraction <45%, nonrestoration of Thrombolysis In Myocardial Infarction flow grade 3, and additional stenting were independent predictors for mortality. The cumulative incidence of ST after DES implantation was 2% at 3 years. No differences were found among stent types. Patient profiles differed between early and late ST. Short-term prognosis is poor, especially when restoration of normal flow fails.

  6. [Evaluation of stents in treating childhood benign esophageal strictures].

    Science.gov (United States)

    Reinshagen, K; Kähler, G; Manegold, B C; Waag, K-L

    2009-01-01

    Esophageal stenting is a popular of treatment of esophageal strictures in adults. It has also been described for children with benign strictures who did not respond to standard dilatation therapy. The aim of the study was to evaluate weather esophageal stents could be used safely and effectively in the treatment of benign esophageal strictures in children. From 1993 to 2005 stenting therapy was performed in 12 children with complicated esophageal strictures. Etiologies of the strictures were caustic burns in 9 patients, postoperative strictures due to complicated esophageal atresia in 2 patients and iatrogenic esophageal injury in 1 patient. Esophageal silicon tubi, covered retrievable expandable nitinol and plastic stents were placed endoscopically. The clinical course and the long term follow up were evaluated retrospectively The stents and tubi were placed in all patients without complications and were later removed successfully. 6 patients were treated with a self expanding plastic stent. The plastic stents showed a distinct tendency to migrate but in 5/6 patients esophageal stricture was treated successfully. 3 patients were treated by a covered self expanding nitinol stent. No migration occurred. One patient was asymptomatic after therapy, one required further dilatation therapy and the third had esophageal resection. 3 patients were treated by esophageal tubi. 2 patients required surgery in the follow up, one patient is asymptomatic. The use of stenting devices in children to treat benign esophageal strictures is safe and efficient. The self expanding plastic stents had the best long term results but required high compliance of parents and children due to the tendency of stent migration. Self expanding nitinol stents are more traumatic at the extraction procedure and are useful in patients with low compliance. Recurrence of strictures occurred most often after esophageal tubi possibly due to the lack of radial expansion.

  7. Endeavour zotarolimus-eluting stent reduces stent thrombosis and improves clinical outcomes compared with cypher sirolimus-eluting stent : 4-year results of the PROTECT randomized trial

    NARCIS (Netherlands)

    Wijns, William; Steg, Ph. Gabriel; Mauri, Laura; Kurowski, Volkhard; Parikh, Keyur; Gao, Runlin; Bode, Christoph; Greenwood, John P.; Lipsic, Erik; Alamgir, Farqad; Rademaker-Havinga, Tessa; Boersma, Eric; Radke, Peter; van Leeuwen, Frank; Camenzind, Edoardo

    2014-01-01

    Aims To compare the long-term clinical safety between two drug-eluting stents with different healing characteristics in the Patient Related Outcomes with Endeavour (E-ZES) vs. Cypher (C-SES) Stenting Trial (PROTECT). At 3 years, there was no difference in the primary outcome of definite or probable

  8. Expandable metallic stents for tracheobronchial stenoses in esophageal cancer.

    Science.gov (United States)

    Takamori, S; Fujita, H; Hayashi, A; Tayama, K; Mitsuoka, M; Ohtsuka, S; Shirouzu, K

    1996-09-01

    Tracheobronchial stenosis in patients with esophageal cancer can be life threatening. Few reports have discussed use of expandable metallic stents for central airway stenoses in patients with esophageal cancer. Twelve patients with esophageal cancer underwent placement of expandable metallic stents for respiratory distress caused by tracheobronchial stricture. Single or double metallic stents were placed in the stenotic airways under fluoroscopic guidance. Improvement in respiratory symptoms and clinical outcome were assessed. Most stenoses were located in the trachea or the left main bronchus. From one to four expandable metallic stents were placed in each stricture site, with immediate relief of respiratory symptoms in 8 patients. One patient with tracheomalacia in alive 3 years after stent placement and another is alive 6 months after stent insertion. The other 10 patients lived from 10 to 70 days (mean; survival, 35 days) after stent placement. Death was due to progression of disease. Although metallic stents are useful for relieving respiratory distress in patients with advanced esophageal cancer, additional therapies should be considered.

  9. The influence of stent design on neointimal hyperplasia of an aortic stent covering the visceral arterial ostia: an experimental study in dogs using a self-expandable nitinol stent

    Energy Technology Data Exchange (ETDEWEB)

    Yin, Yong Hu; Chung, Jin Wook; Choi, Seung Hong; Kim, Kwang Gi; Kim, Hyo Cheol; So, Young Ho; Jae, Hwan Jun; Lee, Whal; Park, Jae Hyung [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    2008-05-15

    To assess the influence of stent design [interlacing (type A) vs. crossing method (type B)] on neointimal hyperplasia using a self-expandable nitinol stent, which crosses the side branches of the abdominal aorta. In seven mongrel dogs, nitinol stents with type A and B intersections were placed in the abdominal aorta across the main branches: 4 Niti-Ms and 3 Niti-Ds. Two months after the stent placement, a DSA was performed for a stent patency evaluation, followed by the extraction of the aortas. The degree of neointimal formation along the wire was evaluated by calculating the area ratio of intimal hyperplasia (type A vs. B). A Student's t-test was employed to investigate the differences in the neointimal hyperplasia between blood types A and B. The total number of wire intersections overlain at the ostia branch ostia was 23 for type A and 36 for type B. The area ratio of the neointimal hyperplasia, for a given area, was 29.09 {+-} 10.82% (type A) and 13.80 {+-} 6.94% (type B) ({rho} < 0.0001)]. Furthermore, the area ratios of the neointimal hyperplasia per area of stent-wire in the given area were 138.38 {+-} 10.84% (type A). 87.58 {+-} 7.36% (type B) ({rho} = 0.0002). In conclusion the interlacing pattern vs. the crossing pattern showed a higher level of neointimal formation than the crossing pattern.

  10. Unilateral versus bilateral stent insertion for malignant hilar biliary obstruction.

    Science.gov (United States)

    Chang, Gang; Xia, Feng-Fei; Li, Hong-Fu; Niu, Su; Xu, Yuan-Shun

    2017-11-01

    To determine the clinical efficiency and long-term outcomes between unilateral and bilateral stent insertion in patients with malignant hilar biliary obstruction. From August 2012 to February 2016, 63 consecutive patients with malignant hilar biliary obstruction were treated with unilateral or bilateral stent insertion at our center. The bilateral stents were inserted using the side-by-side technique. The clinical efficiency and long-term outcomes were compared between the two groups. Unilateral and bilateral stent insertions were successfully performed in 31 of 33 and 27 of 30 patients, respectively (P = 0.912). No procedure-related complication occurred. Clinical success was achieved in 29 of 31 patients in the unilateral stent group and in 26 of 27 patients in the bilateral stent group (P = 0.637). During the follow-up, re-obstruction of stent occurred in five patients in the unilateral stent group and in three patients in the bilateral stent group (P = 0.58). The significant differences were not observed in the stent patency time (368 vs. 387 days, P = 0.685) and survival (200 vs. 198 days, P = 0.751) between two groups. Based on the univariate and multivariate analyses, the independent risk factors for decreasing the survival time included higher Eastern Cooperative Oncology Group performance status (P = 0.018), higher alanine aminotransferase level (P = 0.009), and absence of anticancer treatment after stent insertion (P = 0.002). Compared to bilateral stent insertion for malignant hilar biliary obstruction, unilateral stent insertion can provide comparable clinical efficiency and long-term outcomes.

  11. Usefulness of flexible covered stent in malignant colorectal obstruction

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Jee Hee; Kang, Sung Gwon; Kim, Hyung Jin; Noh, Hong Gi; Woo, Jae Hong; Suh, Chang Hae [Inha Univ. Hospital, Inchon (Korea, Republic of)

    1998-07-01

    To evaluate the usefulness of flexible covered stent in the treatment of acute colorectal obstruction secondary to colorectal carcinoma. Materials and Methods : Flexible covered stents were placed in 11 patients with clinical and radiologic signs of acute colonic obstruction secondary to colorectal carcinoma. The purposes of stent insertion were pre-operative bowel preparation in seven patients and palliative treatment in four. A fistula was present in two;in one this was between the proximal jejunum and colon, and the other was rectovaginal. The usefulness of stent insertion for the purpose of preoperative bowel preparation was evaluated according to the feasibility and status of bowel preparation, as decided by the operator. Palliative treatment for the relief of symptoms of acute bowel obstruction was evaluated according to the number and amount of defecation,bowel dilatation in simple abdomen radiography, and the presence of complications. Results : Bowel preparation for the purpose of preoperative bowel cleansing was easy in seven patients;the fecal materials remaining in the colon presented no problems during surgery. In one of four patients palliative treatment involved a colostomy;this was due to recurrent stent obstruction by fecal materials after three months, and in two other patients there was stent obstruction after two and five months, respectively. The stent in one of four patients who underwent palliative treatment was removed because of stent migration three days after insertion;the stents in two patients with fistulas covered the fistulas successfully. Complications after stent insertion were anal pain in three patients, anal bleeding in three and stent migration in one. Conclusion : The flexible covered stent was an effective device for the relief of acute colonic obstruction secondary to malignant rectosigmoid neoplasia. It allowed for single-stage operation and covered the fistula. We believe however that for further evaluation of the

  12. Self-Expandable Metallic Stent for the Palliative Treatment of Obstructing Left-Sided Colorectal Cancer under Fluoroscopic Guidance: A Comparison of the Clinical Results according to Stent Diameter

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Pyeong Guk; Hong, Hyun Pyo; Choi, Yoon Jung; Lee, Min Hee; Park, Hae Won; Chung, Eun Chul [Kangbuk Samsung Hospital, Seoul (Korea, Republic of); Kim, Sam Soo [Kangwon National University College of Medicine, Chuncheon (Korea, Republic of)

    2010-03-15

    To evaluate the feasibility, effectiveness, and safety of self-expandable metallic stent for the palliative treatment of obstructing left-sided colorectal cancer under fluoroscopic guidance, and to compare results according to the stent diameter. Under fluoroscopic guidance, 31 self-expandable metallic stents were placed into 25 patients for palliative purposes. The rates of technical success, clinical success, complications associated with stent insertion, patient survival, and primary stent patency were evaluated. The results were also compared between two groups: 13 patients using stents with a diameter of 22 mm and 12 patients using stents with a diameter of 26 mm. The technical and clinical success rates were 93.5 and 90.3%, respectively. The complications included severe abdominal pain (6.5%), minor rectal bleeding (9.7%), stent migration (9.7%), and tumor ingrowth or overgrowth (9.7%). No statistical differences in technical were detected between the two groups for the clinical success rate and complication rates. The mean survival time was 5.5 +- 1.4 months. The primary stent patency rates were 91.3% at 5 months, 85.2% at 10 months, and 77.4% at 15 months. The mean period of stent patency was 12.4 +- 2.6 months. The mean period of primary stent patency was 16.4 +- 2.6 months in the 26 mm stent group, and significantly higher than 5.4 +- 1.4 months in the 22 mm stent group (p=0.031). A self-expandable metallic stent under fluoroscopic guidance, for the palliative treatment of obstructing left-sided colorectal cancer, was feasible and effective, and yielded good clinical results. The period of primary stent patency of the 26 mm stent group was longer than the 22 mm stent group, and the complication rate was not significantly different between the two stent groups

  13. Self-Expandable Metallic Stent for the Palliative Treatment of Obstructing Left-Sided Colorectal Cancer under Fluoroscopic Guidance: A Comparison of the Clinical Results according to Stent Diameter

    International Nuclear Information System (INIS)

    Kang, Pyeong Guk; Hong, Hyun Pyo; Choi, Yoon Jung; Lee, Min Hee; Park, Hae Won; Chung, Eun Chul; Kim, Sam Soo

    2010-01-01

    To evaluate the feasibility, effectiveness, and safety of self-expandable metallic stent for the palliative treatment of obstructing left-sided colorectal cancer under fluoroscopic guidance, and to compare results according to the stent diameter. Under fluoroscopic guidance, 31 self-expandable metallic stents were placed into 25 patients for palliative purposes. The rates of technical success, clinical success, complications associated with stent insertion, patient survival, and primary stent patency were evaluated. The results were also compared between two groups: 13 patients using stents with a diameter of 22 mm and 12 patients using stents with a diameter of 26 mm. The technical and clinical success rates were 93.5 and 90.3%, respectively. The complications included severe abdominal pain (6.5%), minor rectal bleeding (9.7%), stent migration (9.7%), and tumor ingrowth or overgrowth (9.7%). No statistical differences in technical were detected between the two groups for the clinical success rate and complication rates. The mean survival time was 5.5 ± 1.4 months. The primary stent patency rates were 91.3% at 5 months, 85.2% at 10 months, and 77.4% at 15 months. The mean period of stent patency was 12.4 ± 2.6 months. The mean period of primary stent patency was 16.4 ± 2.6 months in the 26 mm stent group, and significantly higher than 5.4 ± 1.4 months in the 22 mm stent group (p=0.031). A self-expandable metallic stent under fluoroscopic guidance, for the palliative treatment of obstructing left-sided colorectal cancer, was feasible and effective, and yielded good clinical results. The period of primary stent patency of the 26 mm stent group was longer than the 22 mm stent group, and the complication rate was not significantly different between the two stent groups

  14. [The thermoformable spiral metallic stents in the treatment of localized ureteral stenosis: an alternative to JJ stent? Prospective multicenter study].

    Science.gov (United States)

    Bonniol, R; Meria, P; Safsaf, A; Albouy, B; Sibert, L

    2011-06-01

    Evaluation of the effectiveness and tolerance of thermoformable metallic spiral stents Memokath(®) 051 (Bard, Pnn Medical) in the treatment of localized ureteral stenosis in non-operable patients who have JJ ureteral stents. Prospective, descriptive and multicenter study of patients with ureteral strictures treated with metallic ureteral stents Memokath(®) 051. Assessment criteria (recurrent stenotic, permeability, tolerance) were measured by clinical, biological and radiological examination at 1 month, and then every 3 months. Fifteen stents (average length: 9.15 cm, range 6-15 cm) were implanted in 14 patients (mean age: 55 years, range: 38-72 years) with secondary suspended ureteral stenosis during 2 years in two centers. The median follow-up was 11 months (range 6 to 24 months). Technical difficulty was observed with two patients. Stents are still up in four patients. The stenosis recurred in four patients with spontaneous progression of stenosis but without endoprosthetics tissue invasion. Two and three migration were observed with spontaneous expulsions. Two lower urinary infections and one high occurred, resolved on antibiotic therapy, no inlay or hematuria, no pain (mean VAS score=3/10) or urinary disorders of the lower unit have been identified. Stents Memokath(®) 051 are well tolered and seem to position themselves as an interesting alternative to JJ ureteral stent in some frails patients. The refinement of contraindication should help to improve the stent's efficacity and to reduce the risk of migration and expulsion. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

  15. Fully covered self-expandable metal stents (SEMS), partially covered SEMS and self-expandable plastic stents for the treatment of benign esophageal ruptures and anastomotic leaks.

    Science.gov (United States)

    van Boeckel, Petra G A; Dua, Kulwinder S; Weusten, Bas L A M; Schmits, Ruben J H; Surapaneni, Naveen; Timmer, Robin; Vleggaar, Frank P; Siersema, Peter D

    2012-02-29

    Benign esophageal ruptures and anastomotic leaks are life-threatening conditions that are often treated surgically. Recently, placement of partially and fully covered metal or plastic stents has emerged as a minimally invasive treatment option. We aimed to determine the clinical effectiveness of covered stent placement for the treatment of esophageal ruptures and anastomotic leaks with special emphasis on different stent designs. Consecutive patients who underwent placement of a fully covered self-expandable metal stent (FSEMS), a partially covered SEMS (PSEMS) or a self-expanding plastic stent (SEPS) for a benign esophageal rupture or anastomotic leak after upper gastrointestinal surgery in the period 2007-2010 were included. Data on patient demographics, type of lesion, stent placement and removal, clinical success and complications were collected A total of 52 patients received 83 esophageal stents (61 PSEMS, 15 FSEMS, 7 SEPS) for an anastomotic leak (n=32), iatrogenic rupture (n=13), Boerhaave's syndrome (n=4) or other cause (n=3). Endoscopic stent removal was successful in all but eight patients treated with a PSEMS due to tissue ingrowth. Clinical success was achieved in 34 (76%, intention-to-treat: 65%) patients (PSEMS: 73%, FSEMS: 83%, SEPS: 83%) after a median of 1 (range 1-5) stent and a median stenting time of 39 (range 7-120) days. In total, 33 complications in 24 (46%) patients occurred (tissue in- or overgrowth (n=8), stent migration (n=10), ruptured stent cover (all Ultraflex; n=6), food obstruction (n=3), severe pain (n=2), esophageal rupture (n=2), hemorrhage (n=2)). One (2%) patient died of a stent-related cause. Covered stents placed for a period of 5-6 weeks may well be an alternative to surgery for treating benign esophageal ruptures or anastomotic leaks. As efficacy between PSEMS, FSEMS and SEPS is not different, stent choice should depend on expected risks of stent migration (SEPS and FSEMS) and tissue in- or overgrowth (PSEMS).

  16. Combined Arterial Infusion and Stent Implantation Compared with Metal Stent Alone in Treatment of Malignant Gastroduodenal Obstruction

    International Nuclear Information System (INIS)

    Wang Zhongmin; Chen Kemin; Gong Ju; Zheng Yunfeng; Wang Tianxiang

    2009-01-01

    Many patients with malignant gastroduodenal obstruction have an unresectable primary lesion and distant metastases, which may prompt palliative management to allow the patient to eat and to improve the quality of life. Intraluminal metallic stent implantation (MSI) under fluoroscopic guidance has been reported to be an effective option for symptomatic relief in these patients, with a good safety record. An alternative, dual interventional therapy (DIT), has been used during the last decade, in which prosthesis insertion is followed by intra-arterial chemotherapy via the tumor-feeding arteries. The aim of this study was to compare success rates, complication rates, and survival time between MSI and DIT in patients who presented with gastroduodenal obstruction from advanced upper gastrointestinal tract cancer. All consecutive patients with malignant gastroduodenal obstruction seen at our center between October 2002 and August 2007 were retrospectively studied. Patients were treated palliatively by either MSI or DIT by the patient's or the next of kin's decision. Outcomes included technical and clinical success, complication rates, and survival. Of the 164 patients with malignant gastric and duodenal outlet obstructions, 80 (49%) underwent stent insertion as the primary therapy, while the remaining 84 (51%) received DIT. Clinical characteristics were similar between the two groups. In the MSI cohort initial stent implantation was successful in 73 patients (91%), two stents were used in 5 patients, and delayed additional stent insertion for stent obstruction related to tumor overgrowth was required in 3 patients during follow-up. In the DIT cohort the technical success rate was 94%, 3 patients required two stents, and stent obstruction occurred in 2 patients after initial stent placement. Early postprocedural clinical success, indicated by average dysphagia score, improved significantly in both groups: MSI group, from 4.56 to 1.51 (P < 0.01); and DIT group, from 4

  17. Randomized Comparison of Paclitaxel-Eluting Balloon and Stenting Versus Plain Balloon Plus Stenting Versus Directional Atherectomy for Femoral Artery Disease (ISAR-STATH).

    Science.gov (United States)

    Ott, Ilka; Cassese, Salvatore; Groha, Philipp; Steppich, Birgit; Hadamitzky, Martin; Ibrahim, Tareq; Kufner, Sebastian; Dewitz, Karl; Hiendlmayer, Regina; Laugwitz, Karl-Ludwig; Schunkert, Heribert; Kastrati, Adnan; Fusaro, Massimiliano

    2017-06-06

    Atherosclerosis in the superficial femoral artery is common in patients suffering from peripheral artery disease. Paclitaxel-eluting balloon (PEB) angioplasty, stenting, and directional atherectomy (DA) have provided new options for the treatment of superficial femoral artery disease; however, the comparative efficacy of these interventional strategies remains uncertain. One hundred and fifty-five patients with symptomatic peripheral artery disease due to de novo superficial femoral artery stenotic or occlusive lesions were randomized to treatment with plain balloon angioplasty (BA) followed by PEB angioplasty and stenting (n=48), BA and stenting (n=52), or DA with distal protection and bailout stenting (n=55). The primary end point of the study was percentage diameter stenosis after 6 months measured by angiography. Other end points included target lesion revascularization, thrombosis, ipsilateral amputation, binary restenosis, and all-cause mortality at 6 and 24 months. Baseline and lesion characteristics were comparable in all groups with a mean lesion length of 65.9±46.8 mm and 56% total occlusions. At 6 months angiography, the percent diameter stenosis was significantly lower in patients treated by PEB angioplasty and stenting (34±31%) as compared with BA angioplasty and stenting (56±29%, P =0.009) or DA (55±29%, P =0.007). Similarly, binary restenosis was significantly lower after treatment with PEB and stenting as compared with BA and stenting or DA. Clinical follow-up at 24 months revealed a lower risk for target lesion revascularization after PEB angioplasty and stenting as compared with BA and stenting or DA. We found no difference in terms of target lesion thrombosis and mortality among groups, and no patient underwent amputation. Treatment of de novo superficial femoral artery lesions with PEB angioplasty and stenting is superior to BA angioplasty and stenting or DA in terms of angiographic diameter stenosis at 6 months and target lesion

  18. Successful stent-in-stent insertion of an expandable metallic stent covered with polyuretane placed to obliterate a large bronchial fistula after chemoradiotherapy for inoperable lung cancer

    International Nuclear Information System (INIS)

    Minami, Hiroya; Tsubota, Noriaki; Miyamoto, Yoshifumi; Yoshimura, Masahiro; Obayashi, Kayoko; Takada, Yoshiki

    1999-01-01

    Bronchial fistulas in cases of inoperable lung cancer caused by radiochemotherapy are quite refractory and generally cannot be surgically closed. A 45-year-old man with squamous cell carcinoma in the right lung underwent two courses of induction chemotherapy (135 mg CDDP, 5 mg VDS, 13.5 mg MMC) and radiation therapy (2 Gy x 22 times) for invasion of the right main bronchus, the pulmonary artery and superior vena cava. Just before the end of the second course, the empyem second to the bronchial fistula caused by tumor necrosis developed in the right upper bronchus, and fenestration was performed. After the operation, his condition improved remarkably, however the fistula enlarged into the right main bronchus and the purulent discharge flowed into the left lung. An expandable metallic stent (EMS) covered with polyuretane was inserted in the trachea and the left main bronchus to break aspiration pneumonia. As the covered EMS was too unstable to be fixed, a bare EMS was inserted in a stent-in-stent fashion. After the procedure he was followed at the O.P.D. and lived a relatively comfortable life for 9 months until his death due to tumor. We inserted the covered EMS in a stent-in-stent fashion to successfully obliterate a large bronchial fistula. (author)

  19. Surgical stent for dental implant using cone beam CT images

    International Nuclear Information System (INIS)

    Choi, Hyung Soo; Kim, Gyu Tae; Choi, Yong Suk; Hwang, Eui Hwan

    2010-01-01

    The purpose of this study is to develop a surgical stent for dental implant procedure that can be easily applied and affordable by using cone beam computerized tomography (CBCT). Aluminum, Teflon-PFA (perfluoroalkoxy), and acetal (polyoxymethylene plastic) were selected as materials for the surgical stent. Among these three materials, the appropriate material was chosen using the CBCT images. The surgical stent, which could be easily placed into an oral cavity, was designed with chosen material. CBCT images of the new surgical stent on mandible were obtained using Alphard-3030 dental CT system (Asahi Roentgen Co., Ltd., Kyoto, Japan). The point of insertion was prescribed on the surgical stent with the multiplanar reconstruction software of OnDemand3D (CyberMed Inc., Seoul, Korea). Guide holes were made at the point of insertion on the surgical stent using newly designed guide jig. CBCT scans was taken for the second time to verify the accuracy of the newly designed surgical stent. Teflon-PFA showed radiologically excellent image characteristics for the surgical stent. High accuracy and reproducibility of implantation were confirmed with the surgical stent. The newly designed surgical stent can lead to the accurate implantation and achieve the clinically predictable result.

  20. The study of metal stents for effect to the radiation therapy

    International Nuclear Information System (INIS)

    Gao Li; Feng Ningyuan; Zhai Renyou; Yang Weizhi; Xu Guozhen; Wang Yafei

    2001-01-01

    Objective: To confirm whether the metal stents affect the radiation beam. Methods: The transmission factors from the national self-expanding esophagus stent, stainless self-expanding bile duct stent, and balloon-expanded vascular stent was supervised under 192 Ir irradiation in the air. Results: The transmission factors from the 3 kinds of metal stents were 0.993, 0.988, and 0.997, which meant that the attenuation of the stents to the radiation was 0.7%, 1.2%, and 0.3%, respectively (mean: 0.7%). Conclusion: The effect of the metal stents to the radiation was less than 1.2% and that meant there was no clinical significant effect on the patients irradiated following stent implantation or to perform the intra-stents brachytherapy

  1. Safety and efficacy of everolimus-eluting stents compared with first-generation drug-eluting stents in patients undergoing primary percutaneous coronary intervention

    Energy Technology Data Exchange (ETDEWEB)

    Escárcega, Ricardo O.; Baker, Nevin C.; Magalhaes, Marco A.; Lipinski, Michael J.; Minha, Sa’ar; Torguson, Rebecca; Satler, Lowell F.; Pichard, Augusto D.; Suddath, William O.; Waksman, Ron, E-mail: ron.waksman@medstar.net

    2014-09-15

    Objective: To assess the safety and efficacy everolimus-eluting stents (EES) compared with first-generation drug-eluting stents (DES) in patients with acute myocardial infarction (MI) undergoing primary percutaneous coronary intervention (PCI). Background: EES have been associated with improved clinical outcomes compared to paclitaxel-eluting stents (PES) and with similar outcomes compared to sirolimus-eluting stents (SES). Methods: A total of 520 patients who presented with ST-elevation myocardial infarction (STEMI) from 2003 to 2013, who underwent primary PCI with DES, were retrospectively analyzed. Of these, 247 received SES, 136 PES, and 137 EES. Patients were followed up to 2 years for major adverse cardiac events (MACE). Univariate and multivariate models detected correlates to outcome. Results: EES implantation, compared with PES and SES, resulted in comparable rates of MACE (8.8% vs. 16.2%, p = 0.06 and 8.8% vs. 12.6%, respectively, p = 0.26), stent thrombosis, MI, and target lesion revascularization. Patients who received EES had lower rates of all-cause mortality (3.7% vs. 12.6% vs. 9.4%, p = 0.03) at 1-year follow up. However, in the univariate and multivariate analyses, stent type was not independently associated with the primary outcome or with all-cause mortality. Diabetes mellitus and number of stents implanted were independently associated with the primary outcome. Conclusion: While EES seem to be associated with better outcome when compared to PES, the main correlates of STEMI patients are the presence of diabetes and number of stents implanted, and not the type of stent used for intervention.

  2. Stent placement of gastroenteric anastomoses formed by magnetic compression.

    Science.gov (United States)

    Cope, C; Clark, T W; Ginsberg, G; Habecker, P

    1999-01-01

    To evaluate the use of stents for prolonging the patency of gastroenteric anastomoses (GEA) induced by magnet compression. Rare earth magnets were inserted perorally and serially in 15 dogs so as to mate across the gastric and jejunal walls. After magnet excretion, the resulting GEA was identified endoscopically, dilated (n = 1), and stented with bare (n = 2) or partially covered (n = 6) flared 10-mm or 12-mm Z stents. The GEA was followed at 2-4-week intervals for patency; malfunctioning shunts were irrigated, or dilated with angioplasty balloons. Gross and histologic examination of the anastomotic tissues was performed in 14 animals. Magnet pairs were excreted in 5-7 days. Of the 19 magnet placements in 15 animals, stent placement was not possible because of early GEA closure (n = 6), failure to locate (n = 2), pancreatic abscess (n = 1), and magnet perforation with peritonitis (n = 1). Estimated duration of GEA patency was 19 days after balloon dilation, 40-64 days with bare Z stents, and 58-147 days (mean, 90 days) with partially covered Z stents. Shunt function was commonly hindered by bezoars. Stent narrowing or occlusion was caused by tissue overgrowth through bare stents (n = 2), between covered stent struts and through partially detached membrane (n = 2). Serious morbidity (n = 2) was due to malpositioned magnets across the pancreas in one animal and gastric perforation in the other. One dog was euthanized because of unsuspected kidney infection. Partially covered stents significantly extend the anatomic patency rate of magnetic GEA to 7 weeks or more. Functional patency is frequently impaired by bezoars. Ongoing improvements in covered stent design should provide longer-term GEA patency.

  3. Stenting for curved lesions using a novel curved balloon: Preliminary experimental study.

    Science.gov (United States)

    Tomita, Hideshi; Higaki, Takashi; Kobayashi, Toshiki; Fujii, Takanari; Fujimoto, Kazuto

    2015-08-01

    Stenting may be a compelling approach to dilating curved lesions in congenital heart diseases. However, balloon-expandable stents, which are commonly used for congenital heart diseases, are usually deployed in a straight orientation. In this study, we evaluated the effect of stenting with a novel curved balloon considered to provide better conformability to the curved-angled lesion. In vitro experiments: A Palmaz Genesis(®) stent (Johnson & Johnson, Cordis Co, Bridgewater, NJ, USA) mounted on the Goku(®) curve (Tokai Medical Co. Nagoya, Japan) was dilated in vitro to observe directly the behavior of the stent and balloon assembly during expansion. Animal experiment: A short Express(®) Vascular SD (Boston Scientific Co, Marlborough, MA, USA) stent and a long Express(®) Vascular LD stent (Boston Scientific) mounted on the curved balloon were deployed in the curved vessel of a pig to observe the effect of stenting in vivo. In vitro experiments: Although the stent was dilated in a curved fashion, stent and balloon assembly also rotated conjointly during expansion of its curved portion. In the primary stenting of the short stent, the stent was dilated with rotation of the curved portion. The excised stent conformed to the curved vessel. As the long stent could not be negotiated across the mid-portion with the balloon in expansion when it started curving, the mid-portion of the stent failed to expand fully. Furthermore, the balloon, which became entangled with the stent strut, could not be retrieved even after complete deflation. This novel curved balloon catheter might be used for implantation of the short stent in a curved lesion; however, it should not be used for primary stenting of the long stent. Post-dilation to conform the stent to the angled vessel would be safer than primary stenting irrespective of stent length. Copyright © 2014 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.

  4. Imaging of coronary artery stents using multislice computed tomography: in vitro evaluation

    International Nuclear Information System (INIS)

    Maintz, David; Juergens, Kai-Uwe; Heindel, Walter; Fischbach, Roman; Wichter, Thomas; Grude, Matthias

    2003-01-01

    The aim of this study was to evaluate imaging features of different coronary artery stents during multislice CT Angiography (MSCTA). Nineteen stents made of varying material (steel, nitinol, tantalum) and of varying stent design were implanted in plastic tubes with an inner diameter of 3 mm to simulate a coronary artery. The tubes were filled with iodinated contrast material diluted to 200 Hounsfield units (HU), closed at both ends and positioned in a plastic container filled with oil (-70 HU). The MSCT scans were obtained perpendicular to the stent axes (detector collimation 4 x 1 mm, table feed 2 mm/rotation, 300 mAs, 120 kV). Axial images and multiplanar reformations were evaluated regarding artifact size, lumen visibility, and intraluminal attenuation values. Artifacts characterized by artifactual thickening of the stent struts leading to apparent reduction in the lumen diameter and increased intraluminal attenuation values were observed in all cases. The stent lumen was totally obscured in the Wiktor stent, the Wallgraft stent, and the Nir Royal stent. Partial residual of the stent lumen could be visualized in all other utilized stent products (artificial lumen reductions ranged from 62% in the V-Flex stent to 94% in the Bx Velocity stent). Parts of the stent lumen can be visualized in most coronary artery stents; however, detectability of in-stent stenoses remains to be evaluated for each stent type. (orig.)

  5. Outcomes of second self-expandable metallic stent insertion for malignant gastric outlet obstruction.

    Science.gov (United States)

    Kim, Chan Gyoo; Choi, Il Ju; Lee, Jong Yeul; Cho, Soo-Jeong; Kim, Soo Jin; Kim, Mi-Jung; Park, Sook Ryun; Park, Young Lee

    2014-01-01

    Self-expandable metallic stents are used widely to relieve malignant gastric outlet obstruction (GOO). However, restenosis or migration of first stents is a frequent complication. The purpose of this retrospective cohort study was to evaluate the effectiveness of second stents as an approach to manage failure of first stents in patients with malignant GOO. A total of 222 patients with gastric cancer received first stents due to inoperable GOO at National Cancer Center in Korea between January 2008 and June 2011. Monthly follow-up interviews were performed, and second stents (stent-in-stent or stent-after-migration) were inserted in 59 patients by June 2012. Technical and clinical successes and long-term complications were evaluated. The technical and immediate clinical success rates were 98.3 % (58/59) and 91.5 % (54/59), respectively. Patients who received a second stent due to late complications involving the first stent (migration, restenosis, and fracture) showed a higher clinical success rate (95.8 % [46/48]) than patients who received a second stent due to immediate clinical failure of the first stent (72.7 % [8/11], p = 0.04). The immediate clinical success rate of stent-after-migration (100 % [11/11]) was not different from that of stent-in-stent (89.6 % [43/48], p = 1.0). The stent dysfunction rate of stent-after-migration (27.3 % [3/11]) also was similar to that of stent-in-stent (29.2 % [14/48], p = 1.0). The median patencies of stent-in-stent and stent-after-migration were 27.4 and 58.4 weeks, respectively (p = 0.177). There were no significant prognostic factors for patency of second stents. Insertion of a second stent is effective for treating the first-stent failure in gastric cancer patients with GOO, especially if the immediate outcome of the first stent was successful.

  6. Absorbable stent: focus on clinical applications and benefits

    Directory of Open Access Journals (Sweden)

    Gonzalo N

    2012-02-01

    Full Text Available Nieves Gonzalo, Carlos MacayaInterventional Cardiology, Cardiovascular Institute. Hospital Clinico San Carlos, Instituto de Investigación Sanitaria del Hospital Clinico San Carlos, Madrid, SpainAbstract: Coronary stents have improved very significantly the immediate and long-term results of percutaneous coronary interventions. However, once the vessel has healed, the scaffolding function of the stent is no longer needed, and the presence of a permanent metallic prosthesis poses important disadvantages. This has led to the idea of creating new devices that are able to provide mechanical support for a determined period and then disappear from the vessel, allowing its natural healing and avoiding the risks associated with having a permanent metallic cage, such as stent thrombosis. Absorbable stents currently appear as one of the most promising fields in interventional cardiology. The present article will review the available clinical evidence regarding these devices at present and their future perspectives.Keywords: absorbable stent, bioresorbable stent, absorb, percutaneous coronary intervention

  7. Tracheoesophageal Fistula due to a Damaged Tracheal Stent

    Directory of Open Access Journals (Sweden)

    Masahiro Kimura

    2014-01-01

    Full Text Available We describe the management of a tracheoesophageal fistula due to a damaged tracheal stent, which was first inserted to treat tracheal stenosis. A 29-year-old woman with a history of treated epilepsy had a seizure and suffered from smoke inhalation during a fire. Breathing difficulties appeared and gradually worsened; consultation was obtained two years afterward. After undergoing a thorough examination, the patient was diagnosed with tracheal strangulation. A noncovered, metallic stent was inserted. When the patient was 37 years old, she was admitted to our hospital for the treatment of a tracheoesophageal fistula. We diagnosed it as a tracheoesophageal fistula due to the collapse of the damaged tracheal stent toward the esophageal side, and we decided to perform a mediastinal tracheostomy. Granulation may be formed in the circumference of a stent that has been present for a prolonged period, and removal of the stent may become difficult. This case suggests that insertion of a noncovered, metallic stent is contraindicated for a benign disease.

  8. [Eight Cases of Esophagus and Tracheobronchial Stenting for Advanced Esophageal Cancer].

    Science.gov (United States)

    Nakahara, Yujiro; Takachi, Ko; Tsujimura, Naoto; Wakasugi, Masaki; Hirota, Masaki; Matsumoto, Takashi; Takemoto, Hiroyoshi; Nishioka, Kiyonori; Oshima, Satoshi

    2017-11-01

    Malignant stricture and fistula of the esophagus and tracheobronchus adversely affect the quality of life(QOL)in patients with advanced esophageal cancer. Stenting is one ofthe therapies available for these patients. We investigated the outcomes ofesophagus and tracheobronchial stenting in our institution. Eight patients with advanced esophageal cancer underwent double stenting from 2010 to 2016. Among them, 4 patients underwent double stenting as planned. One patient underwent an emergency tracheal stenting because ofstenosis ofthe trachea caused by esophageal stenting. Three patients underwent tracheobronchial stenting later on because ofan increase in the tumor size after esophageal stenting. Dysphagia score was improved in 5(67.5%)out ofthe 8 patients. Respiratory symptoms were improved in all patients, and 4 patients(50.0%) were discharged. The median survival time after esophageal stenting was 70.5 days. Esophagus and tracheobronchial stenting for advanced esophageal cancer was useful for the improvement of the QOL.

  9. Square Stent: A New Self-Expandable Endoluminal Device and Its Applications

    International Nuclear Information System (INIS)

    Pavcnik, Dusan; Uchida, Barry; Timmermans, Hans; Keller, Frederick S.; Roesch, Josef

    2001-01-01

    The square stent is a new, simply constructed, self-expanding device that has recently been described. Compared with other stents, the square stent has a minimal amount of metal and thus requires a smaller-diameter catheter for introduction. Despite the small amount of metal present, the square stent has adequate expansile force. We have been evaluating the square stent for various interventional applications. In addition to the basic square stent, combinations of square stents and coverings for square stents were developed and evaluated to expand its uses and indications. One of the coverings tested is a new biomaterial: small intestinal submucosa (SIS). This paper will discuss the various applications of the square stent, which include a retrievable inferior vena cava filter, vascular occluder, graft adapter, and venous and aortic valves. In addition, we will review the important properties of SIS as a covering for the square stent

  10. Ureteral stent retrieval using the crochet hook technique in females.

    Directory of Open Access Journals (Sweden)

    Takashi Kawahara

    Full Text Available INTRODUCTION: We developed a method for ureteral stent removal in female patients that requires no cystoscopy or fluoroscopic guidance using a crochet hook. In addition, we also investigated the success rate, complications and pain associated with this procedure. METHODS: A total of 40 female patients (56 stents underwent the removal of ureteral stents. All procedures were carried out with the patients either under anesthesia, conscious sedation, or analgesic suppositories as deemed appropriate for each procedure including Shock Wave Lithotripsy (SWL, Ureteroscopy (URS, Percutaneous Nephrolithotomy (PCNL, and ureteral stent removal. At the time of these procedures, fluoroscopy and/or cystoscopy were prepared, but they were not used unless we failed to successfully remove the ureteral stent using the crochet hook. In addition, matched controls (comprising 50 stents which were removed by standard ureteral stent removal using cystoscopy were used for comparison purposes. RESULTS: A total of 47 of the 56 stents (83.9% were successfully removed. In addition, 47 of 52 (90.4% were successfully removed except for two migrated stents and two heavily encrusted stents which could not be removed using cystoscopy. Ureteral stent removal using the crochet hook technique was unsuccessful in nine patients, including two encrustations and two migrations. Concerning pain, ureteral stent removal using the crochet hook technique showed a lower visual analogue pain scale (VAPS score than for the standard technique using cystoscopy. CONCLUSIONS: Ureteral stent removal using a crochet hook is considered to be easy, safe, and cost effective. This technique is also easy to learn and is therefore considered to be suitable for use on an outpatient basis.

  11. Ferromagnetic Bare Metal Stent for Endothelial Cell Capture and Retention.

    Science.gov (United States)

    Uthamaraj, Susheil; Tefft, Brandon J; Hlinomaz, Ota; Sandhu, Gurpreet S; Dragomir-Daescu, Dan

    2015-09-18

    Rapid endothelialization of cardiovascular stents is needed to reduce stent thrombosis and to avoid anti-platelet therapy which can reduce bleeding risk. The feasibility of using magnetic forces to capture and retain endothelial outgrowth cells (EOC) labeled with super paramagnetic iron oxide nanoparticles (SPION) has been shown previously. But this technique requires the development of a mechanically functional stent from a magnetic and biocompatible material followed by in-vitro and in-vivo testing to prove rapid endothelialization. We developed a weakly ferromagnetic stent from 2205 duplex stainless steel using computer aided design (CAD) and its design was further refined using finite element analysis (FEA). The final design of the stent exhibited a principal strain below the fracture limit of the material during mechanical crimping and expansion. One hundred stents were manufactured and a subset of them was used for mechanical testing, retained magnetic field measurements, in-vitro cell capture studies, and in-vivo implantation studies. Ten stents were tested for deployment to verify if they sustained crimping and expansion cycle without failure. Another 10 stents were magnetized using a strong neodymium magnet and their retained magnetic field was measured. The stents showed that the retained magnetism was sufficient to capture SPION-labeled EOC in our in-vitro studies. SPION-labeled EOC capture and retention was verified in large animal models by implanting 1 magnetized stent and 1 non-magnetized control stent in each of 4 pigs. The stented arteries were explanted after 7 days and analyzed histologically. The weakly magnetic stents developed in this study were capable of attracting and retaining SPION-labeled endothelial cells which can promote rapid healing.

  12. Long-Term Results after Placement of Aortic Bifurcation Self-Expanding Stents: 10 Year Mortality, Stent Restenosis, and Distal Disease Progression

    International Nuclear Information System (INIS)

    Houston, J. Graeme; Bhat, Raj; Ross, Rose; Stonebridge, Peter A.

    2007-01-01

    Purpose. To retrospectively evaluate the 10 year follow-up results in patients who had 'kissing' self-expanding stent aortic bifurcation reconstruction. Methods. Forty-three patients were treated with 'kissing' self-expanding stents for aortoiliac occlusive disease. Early follow-up with clinical and ankle brachial pressure indices (ABPI) was performed at 3, 6, 12, and 24 months and with intra-arterial digital subtraction angiography at 12-24 months; clinical and angiographic follow-up was performed for symptom recurrence up to 10 years after treatment. Retrospective record review was performed to assess mortality, clinical patency, angiographic patency, and secondary assisted patency of both stents and downstream peripheral vessels at 5 and 10 years follow-up. Results. The 2 year primary angiographic and secondary assisted stent patencies were 89% and 93%, respectively. At 10 years follow-up in 40 patients the mortality was 38% (due to myocardial infarction, stroke, chronic renal failure, malignancy, and liver failure). At 5 and 10 years follow-up the primary clinical stent patency was 82% and 68%, and the secondary assisted stent patency 93% and 86%, respectively. At 5 and 10 years, the distal vessel patency was 86% and 72%, and the secondary assisted distal vessel patency treated by surgical or endovascular techniques was 94% and 88%, respectively. At 10 years there was no limb loss. Conclusion. The long-term (10 year) results of aortic bifurcation arterial self-expanding stent placement in patients with arterial occlusive disease show a 10 year primary stent patency rate of 68% but a secondary assisted patency rate of 86%. In addition there is a high overall mortality due to other cardiovascular causes and the rate of distal disease progression and loss of patency is similar to the loss of stent patency rate

  13. Long term follow-up of bifurcation aneurysms treated with braided stent assisted coiling and complex T- and Y- stent constructs.

    Science.gov (United States)

    Cheung, Nicholas K; Chiu, Albert Hy; Cheung, Andrew; Wenderoth, Jason D

    2018-06-01

    Stent assisted coil embolization (SACE) of bifurcation aneurysms is challenging. Heterogeneous results have been achieved to date, but largely for laser cut stents. While braided stents offer multiple technical advantages, their long term efficacy has yet to be validated. To report the first long term 18 month results for the durability of bifurcation aneurysms treated with braided stents. Over a 4 year period, 59 consecutive patients with 60 bifurcation aneurysms underwent elective braided SACE across three Australian neurovascular centers. 17 of these aneurysms underwent T- or Y-shaped stent constructs. All patients had immediate, 6 month and 18 month clinical and radiological follow-up. Radiological assessment was made on modified Raymond-Roy occlusion scores while clinical assessment was based on the modified Rankin Scale. Subgroup analysis of 17 aneurysms treated with multi-stent constructs was conducted. 6 month follow-up data were available for 59 aneurysms and 18 month follow-up data for 58 aneurysms. Satisfactory aneurysm occlusion was achieved in 97% at inception and at 6 months, and 98% at 18 months. Good neurological outcomes were achieved in 95% at 18 months. Similar satisfactory results were achieved with the multi-stent construct cohort. Intraprocedural thromboembolic events were recorded in 5% and delayed events in 2%. Technical complications were found in 5%. All complication rate was 13%. Braided SACE was safe, efficacious, and durable at the long term 18 month follow-up, including for multi-stent constructs. Preliminary results indicate favorable clinical and radiological outcomes compared with laser cut stents. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  14. Zotarolimus-eluting durable-polymer-coated stent versus a biolimus-eluting biodegradable-polymer-coated stent in unselected patients undergoing percutaneous coronary intervention (SORT OUT VI)

    DEFF Research Database (Denmark)

    Raungaard, Bent; Jensen, Lisette Okkels; Tilsted, Hans-Henrik

    2015-01-01

    BACKGROUND: New-generation drug-eluting coronary stents have reduced the risk of coronary events, especially in patients with complex disease or lesions. To what extent different stent platforms, polymers, and antiproliferative drugs affect outcomes, however, is unclear. We investigated the safety...... and efficacy of a third-generation stent by comparing a highly biocompatible durable-polymer-coated zotarolimus-eluting stent with a biodegradable-polymer-coated biolimus-eluting stent. METHODS: This open-label, randomised, multicentre, non-inferiority trial was done at three sites across western Denmark. All......-polymer zotarolimus-eluting stent or the biodegradable-polymer biolimus-eluting stent. The primary endpoint was a composite of safety (cardiac death and myocardial infarction not clearly attributable to a non-target lesion) and efficacy (target-lesion revascularisation) at 12 months, analysed by intention to treat...

  15. Removal of self expandable metallic airway stent: A rare case report

    Directory of Open Access Journals (Sweden)

    Rakesh K Chawla

    2013-01-01

    Full Text Available Covered self expandable metallic airway stents (SEMS have been used for benign tracheal stenosis, post intubation tracheal stenosis, tracheal burn or trauma, tracheo-broncho-malacia, and extrinsic compression of trachea. Their placement is considered to be permanent, with open surgery the only way to remove the stent, though there are few cases reports of their removal with the bronchoscope, but the complications after their removal are very high. In our patient, one and a half years after placement of SEMS, she developed cough with dyspnoea, video bronchoscopy showed stenosis above the level of stent with granulation tissue inside the stent, stent fracture in lower part and stent migration to right main bronchus, thus she had all conceivable complications of stent placement. The stent was removed with the help of rigid bronchoscope under general anaesthesia. She was discharged the following day. The case is being reported because it was unique in having all the possible complications of stent placement, and rare as we could take out the stent in Toto. Thirdly, the stent could be removed without any complication.

  16. Stent graft placement for dysfunctional arteriovenous grafts

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, Gyeong Sik [Dept. of Radiology, CHA Bundang Medical Center, College of Medicine, CHA University, Seongnam (Korea, Republic of); Shin, Byung Seok; Ohm, Joon Young; Ahn, Moon Sang [Chungnam National University Hospital, Daejeon (Korea, Republic of)

    2015-07-15

    This study aimed to evaluate the usefulness and outcomes of stent graft use in dysfunctional arteriovenous grafts. Eleven patients who underwent stent graft placement for a dysfunctional hemodialysis graft were included in this retrospective study. Expanded polytetrafluoroethylene covered stent grafts were placed at the venous anastomosis site in case of pseudoaneurysm, venous laceration, elastic recoil or residual restenosis despite the repeated angioplasty. The patency of the arteriovenous graft was evaluated using Kaplan-Meier analysis. Primary and secondary mean patency was 363 days and 741 days. Primary patency at 3, 6, and 12 months was 82%, 73%, and 32%, respectively. Secondary patency at the 3, 6, 12, 24, and 36 months was improved to 91%, 82%, 82%, 50%, and 25%, respectively. Fractures of the stent graft were observed in 2 patients, but had no effect on the patency. Stent graft placement in dysfunctional arteriovenous graft is useful and effective in prolonging graft patency.

  17. Invention of a nasolacrimal stent retrieval hook

    International Nuclear Information System (INIS)

    Kim, Tae Hyung; Kim, Yeong Kyun; Park, Sang Soo; Song, Ho Young

    1997-01-01

    To evaluate the clinical usefulness of a nasolacrimal stent retrieval hook The retrieval hook consisted of two parts, a hook and pusher. The head of the hook part was made of 0.7mm stainless steel wire and was question mark-shaped, while the body of this part was constructed by soldering together four stainless steel pipes ranging in thickness from 1.25 to 3.5mm, serially. The pusher part was made of two plastic tubes and was designed in such a way that the hook grasped the stent tightly. The device was used to remove 46 stents in 40 patients, and tested for 1) average number of trials;2) success rate;and 3) average time of the procedure. The average number of trials, success rate, and average time taken to remove the stent was 4.7, 91%, and 1.8 minutes, respectively. In the removal of nasolacrimal stents, the retrieval hook was easy to use, useful and effective

  18. External stent for repair of secondary tracheomalacia.

    Science.gov (United States)

    Johnston, M R; Loeber, N; Hillyer, P; Stephenson, L W; Edmunds, L H

    1980-09-01

    Tracheomalacia was created in anesthetized piglets by submucosal resection of 3 to 5 tracheal cartilages. Measurements of airway pressure and flow showed that expiratory airway resistance is maximal at low lung volumes and is significantly increased by creation of the malacic segment. Cervical flexion increases expiratory airway resistance, whereas hyperextension of the neck reduces resistance toward normal. External stenting of the malacic segment reduces expiratory airway resistance, and the combination of external stenting and hyperextension restores airway resistance to normal except at low lung volume. Two patients with secondary tracheomalacia required tracheostomy and could not be decannulated after the indication for the tracheostomy was corrected. Both were successfully decannulated after external stenting of the malacic segment with rib grafts. Postoperative measurements of expiratory pulmonary resistance show a marked decrease from preoperative measurements. External stenting of symptomatic tracheomalacia reduces expiratory airway resistance by supporting and stretching the malacic segment and is preferable to prolonged internal stenting or tracheal resection.

  19. Progress in the study of drug-eluting intra-stent thrombosis

    International Nuclear Information System (INIS)

    Guo Zhifu; Zheng Xing; Qin Yongwen

    2007-01-01

    Durg-eluting stent has been regarded as the milestone in the history of PCI for their efficiency in the prevention of coronary arterial restenosis after percutaneous coronary intervention. But unfortunately intra-stent thrombosis continues to be a serious complication of contemporary DES use. The incidence of drug-eluting stents thrombosis is at least not lower than that of bare metal stents at present. The clinical consequences of stent thrombosis are frequently catastrophic, including death in 40% to 50% of the cases or major myocardial infarction in 60% to 70%. Premature discontinuation of standard antiplatelet therapy is by far the most important predictor of stent thrombosis with DES and other predictors included renal failure, diabetes, bifurcation lesions, multiple lesions or multivessel disease, long stents, female, advanced age, stent underexpansion and residual stenosis etc. The delayed endothelialization may be the underling mechanism of DES thrombosis. (authors)

  20. Nasolacrimal Polyurethane Stent: Complications with CT Correlation

    International Nuclear Information System (INIS)

    Pinto, Isabel T.; Paul, Laura; Grande, Carlos

    1998-01-01

    Purpose: To evaluate initial results in patients with epiphora secondary to obstruction of the nasolacrimal duct treated by placement of a polyurethane stent, and to discuss the technical problems and complications arising during the procedure, with visualization of the anatomy of the drainage apparatus using computed tomography (CT). Methods: We inserted 20 polyurethane Song stents under fluoroscopic guidance after dacryocystography in 19 patients with grade 3-4 epiphora caused by idiopathic obstruction of the nasolacrimal duct. CT scans were obtained following stent placement in all patients. Results: We focus on the technical problems and complications that arose during these procedures. During negotiation of the guidewire past the obstruction at the level of the junction of the duct with the lacrimal sac, the guidewire created a false passage in a posterior suborbital direction in two cases and towards the posterior midline in another. In all cases the guidewire was withdrawn and reinserted through the proper anatomic route without further difficulty or complications. In two cases the stent was improperly positioned wholly or partially outside the nasolacrimal system (one medially, one posteriorly). In one case the stent was removed and reinserted; in the other it remains in place and functional. CT was performed in all these cases to ensure proper anatomic alignment and determine what had gone wrong. The epiphora was completely resolved in 13 cases and partially relieved in four; there were three cases of stent obstruction. Epistaxis of short duration (1 hr) occurred in seven patients and headache in one. Conclusions: Treatment of epiphora with polyurethane stents is a technique that is well tolerated by patients and achieves a high success rate, yet problems in placement may be encountered. Though no major consequences for patients are involved, cognizance of such difficulties is important to avoid incorrect positioning of stents

  1. Renal artery stent angioplasty for renovascular hypertension

    International Nuclear Information System (INIS)

    Li Gang; Li Haiqing; Wang Lin

    2005-01-01

    Objective: To evaluate the therapeutic results of expandable stent for treatment of atherosclerotic renovascular obstructive disease. Methods: 15 patients (10 men and 5 women, 41-75 years old; mean age, 52 years) with renal arterial hypertension underwent renal stent angioplasty including renal arterial stenosis 89%(n=13) and fully obstruction without function in 2, of which 2 patients had bilateral involvement. The stenotic range of all arterial segments showed 60% to 90% width of the normal arterial diameter. 16 stents were implanted under the guidance of fluoroscopy. The most of stents implanted were Palmaz (n=12, 75%) with regular clinical and angiographic follow up. Results: Technical success (residual stenosis <30%) was achieved in all patients without serious complication. During the follow-up (6-15 months; mean, 8 ± 4 months), hypertension was improved in 9 patients and cured in 4 patients with a total benefit of 86% and no efficacy in 2(13%). The average systolic blood pressure decreased from 27.12 ± 3.09 kPa to 18.62 ± 3.12 kPa and the average diastolic blood pressure decreased from 17.73 ± 1.92 kPa to 11.12 ± 2.43 kPa after stent treatment (P<0.05). Serum creatinine remained stable in 60% (n=9) patients with improvement in 33% (n=5) and worsened in 6% (n=1) patients. Follow-up angiography was performed in all patients with 1 case of a restenosis. 6 months after expanding through stent by using balloon, the two follow up angiographies showed a stable restenosis about 20%. Conclusions: Percutaneous transluminal stent placement is highly beneficial for patients who had renal arterial obstructive disease. The success of stent angioplasty of complete obstructive renal arteries reveals wide prospects for interventional method. (authors)

  2. Revisiting the tethered ureteral stents in children: a novel modification.

    Science.gov (United States)

    Kajbafzadeh, Abdol-Mohammad; Nabavizadeh, Behnam; Keihani, Sorena; Hosseini Sharifi, Seyed Hossein

    2015-06-01

    To propose a simple noninvasive method for ureteral stent retrieval using an extraction string sutured to the skin in children. A retrospective chart review was performed to gather relevant data from December 2005 to February 2013. After the surgeries, if indicated, a tethered double-J stent was placed in the ureter. A 5-0 non-absorbable Prolene stitch was used as an extraction string passing through the urethra and was sutured to subcoronal skin in boys or inner surface of labia majora in girls. For stent removal, a small amount of 2 % lidocaine jelly was pushed into the urethra 5 min before the procedure. The string was then pulled by continuous and gentle force until the entire stent was out. The suture was then cut to release the stent. No sedation or anesthesia was needed. A total of 378 double-J stents with extraction strings were inserted for a total of 325 patients (61.2 % male). Of the 53 patients with bilateral ureteral stents, one male patient (1.88 %) experienced early stent protrusion from urethral meatus. Two of 272 patients (0.73 %) with unilateral ureteral stent (one male and one female) encountered the same problem. All other stents were extracted successfully using the extraction string without any complications. No upward stent migration or suture site reaction was encountered. This method is a safe, easy-to-use, feasible and noninvasive alternative for cystoscopic stent removal with high success rate and minimal complications. This can lead to considerable saving in time and costs for patients, families and healthcare system.

  3. In-hospital management and outcome of patients on warfarin undergoing coronary stent implantation: results of the multicenter, prospective WARfarin and coronary STENTing (WAR-STENT) registry.

    Science.gov (United States)

    Rubboli, Andrea; Sciahbasi, Alessandro; Briguori, Carlo; Saia, Francesco; Palmieri, Cataldo; Moroni, Luigi Andrea; Calabrò, Paolo; Leone, Antonio Maria; Franco, Nicoletta; Valgimigli, Marco; Varani, Elisabetta; Santi, Michela; Pasqualini, Paola; Capecchi, Alessandro; Piccalò, Giacomo; Margheri, Massimo; di Pasquale, Giuseppe; Galvani, Marcello; Bolognese, Leonardo; Gonzini, Lucio; Maggioni, Aldo Pietro

    2013-04-01

    The in-hospital management of patients on warfarin undergoing coronary stent implantation (PCI-S) is variable, and the in-hospital outcome incompletely defined. To determine the adherence to the current recommendations, and the incidence of adverse events, we carried out the prospective, multicenter, observational WARfarin and coronary STENTing (WAR-STENT) registry (ClinicalTrials.gov identifier NCT00722319). All consecutive patients on warfarin undergoing PCI-S at 37 Italian centers were enrolled and followed for 12 months. Outcome measures were: major adverse cardiovascular events (MACE), including cardiovascular death, non-fatal myocardial infarction, need for urgent revascularization, stroke, and venous thromboembolism, and major and minor bleeding. In this paper, we report the in-hospital findings. Out of the 411 patients enrolled, 92% were at non-low (ie, moderate or high) thromboembolic risk. The radial approach and bare-metal stents were used in 61% and 60% of cases, respectively. Drug-eluting stents were essentially reserved to patients with diabetes, which in turn, significantly predicted the implantation of drug-eluting stents (odds ratio [OR], 2.02; 95% confidence interval [CI], 1.29-3.17; P=.002). The in-hospital MACE and major bleeding rates were 2.7% and 2.1%, respectively. At discharge, triple therapy (TT) of warfarin, aspirin, and clopidogrel was prescribed to 76% of patients. Prescription of TT was significantly more frequent in the non-low thromboembolic risk group. Non-low thromboembolic risk, in turn, was a significant predictor of TT prescription (OR, 11.2; 95% CI, 4.83-26.3; P<.0001). In conclusion, real-world warfarin patients undergoing PCI-S are largely managed according to the current recommendations. As a consequence, the risk of in-hospital MACE and major bleedings appears limited and acceptable.

  4. Bioabsorbable Stent Quo Vadis: A Case for Nano-Theranostics

    Science.gov (United States)

    Gundogan, Buket; Tan, Aaron; Farhatnia, Yasmin; Alavijeh, Mohammad S.; Cui, Zhanfeng; Seifalian, Alexander M.

    2014-01-01

    Percutaneous coronary intervention (PCI) is one of the most commonly performed invasive medical procedures in medicine today. Since the first coronary balloon angioplasty in 1977, interventional cardiology has seen a wide array of developments in PCI. Bare metal stents (BMS) were soon superseded by the revolutionary drug-eluting stents (DES), which aimed to address the issue of restenosis found with BMS. However, evidence began to mount against DES, with late-stent thrombosis (ST) rates being higher than that of BMS. The bioabsorbable stent may be a promising alternative, providing vessel patency and support for the necessary time required and thereafter degrade into safe non-toxic compounds which are reabsorbed by the body. This temporary presence provides no triggers for ST, which is brought about by non-endothelialized stent struts and drug polymers remaining in vivo for extended periods of time. Likewise, nano-theranostics incorporated into a bioabsorbable stent of the future may provide an incredibly valuable single platform offering both therapeutic and diagnostic capabilities. Such a stent may allow delivery of therapeutic particles to specific sites thus keeping potential toxicity to a minimum, improved ease of tracking delivery in vivo by embedding imaging agents, controlled rate of therapy release and protection of the implanted therapy. Indeed, nanocarriers may allow an increased therapeutic index as well as offer novel post-stent implantation imaging and diagnostic methods for atherosclerosis, restenosis and thrombosis. It is envisioned that a nano-theranostic stent may well form the cornerstone of future stent designs in clinical practice. PMID:24672583

  5. The influence of stent design on neointimal hyperplasia of an aortic stent covering the visceral arterial ostia: an experimental study in dogs using a self-expandable nitinol stent

    International Nuclear Information System (INIS)

    Yin, Yong Hu; Chung, Jin Wook; Choi, Seung Hong; Kim, Kwang Gi; Kim, Hyo Cheol; So, Young Ho; Jae, Hwan Jun; Lee, Whal; Park, Jae Hyung

    2008-01-01

    To assess the influence of stent design [interlacing (type A) vs. crossing method (type B)] on neointimal hyperplasia using a self-expandable nitinol stent, which crosses the side branches of the abdominal aorta. In seven mongrel dogs, nitinol stents with type A and B intersections were placed in the abdominal aorta across the main branches: 4 Niti-Ms and 3 Niti-Ds. Two months after the stent placement, a DSA was performed for a stent patency evaluation, followed by the extraction of the aortas. The degree of neointimal formation along the wire was evaluated by calculating the area ratio of intimal hyperplasia (type A vs. B). A Student's t-test was employed to investigate the differences in the neointimal hyperplasia between blood types A and B. The total number of wire intersections overlain at the ostia branch ostia was 23 for type A and 36 for type B. The area ratio of the neointimal hyperplasia, for a given area, was 29.09 ± 10.82% (type A) and 13.80 ± 6.94% (type B) (ρ < 0.0001)]. Furthermore, the area ratios of the neointimal hyperplasia per area of stent-wire in the given area were 138.38 ± 10.84% (type A). 87.58 ± 7.36% (type B) (ρ = 0.0002). In conclusion the interlacing pattern vs. the crossing pattern showed a higher level of neointimal formation than the crossing pattern

  6. Broken Esophageal Stent Successfully Treated by Interventional Radiology Technique

    International Nuclear Information System (INIS)

    Zelenak, Kamil; Mistuna, Dusan; Lucan, Jaroslav; Polacek, Hubert

    2010-01-01

    Esophageal stent fractures occur quite rarely. A 61-year-old male patient was previously treated for rupture of benign stenosis, occurring after dilatation, by implanting an esophageal stent. However, a year after implantation, the patient suffered from dysphagia caused by the broken esophageal stent. He was treated with the interventional radiology technique, whereby a second implantation of the esophageal stent was carried out quite successfully.

  7. The role of airway stenting in pediatric tracheobronchial obstruction.

    Science.gov (United States)

    Antón-Pacheco, Juan L; Cabezalí, Daniel; Tejedor, Raquel; López, María; Luna, Carmen; Comas, Juan V; de Miguel, Eduardo

    2008-06-01

    Tracheobronchial obstruction is infrequent in the pediatric age group but it is associated with significant morbidity and mortality. The purpose of this study is to review the results of a single institution experience with endoscopic stent placement in children with benign tracheobronchial obstruction, and with special concern on safety and clinical effectiveness. Twenty-one patients with severe airway stenosing disease in which stent placement was performed between 1993 and 2006. Inclusion criteria according to the clinical status were: failure to wean from ventilation, episode of apnea, frequent respiratory infections (>3 pneumonia/year), and severe respiratory distress. Additional criteria for stent placement were: failure of surgical treatment, bronchomalacia, and tracheomalacia refractory to previous tracheostomy. Selection of the type of stent depended on the site of the lesion, the patient's age, and the stent availability when time of presentation. The following variables were retrospectively evaluated: age, type of obstruction, associated malformations, stent properties, technical and clinical success, complications and related reinterventions, outcome and follow-up period. Thirty-three stents were placed in the trachea (n=18) and/or bronchi (n=15) of 21 patients with a median age of 6 months (range, 9 days-19 years). Etiology of the airway obstruction included severe tracheomalacia and/or bronchomalacia in 19 cases (90%), and postoperative tracheal stenosis in two. Twelve children had a total of 20 balloon-expandable metallic stents placed, and 10 had 13 silicone-type stents (one patient had both). In nine patients (42%) more than one device was placed. Stent positioning was technically successful in all but one patient. Clinical improvement was observed in 18 patients (85%) but complications occurred in five of them (27%). Eight patients died during follow-up but only in one case it was related to airway stenting. Thirteen patients (62%) are alive and

  8. All-cause mortality after drug-eluting stent implantation in African-Americans.

    Science.gov (United States)

    Poludasu, Shyam; Cavusoglu, Erdal; Khan, Waqas; Marmur, Jonathan D

    2008-12-01

    Recent studies have questioned the safety of drug-eluting stents because of a higher incidence of late stent thrombosis, raising the possibility that drug-eluting stents may be associated with an increased mortality. The effect of drug-eluting stents on mortality in African-Americans is unknown. We evaluated 628 African-American patients (354 patients treated with drug-eluting stents and 274 patients treated with bare metal stents) between January 2003 and August 2005, using data from our bolus-only platelet glycoprotein IIb/IIIa inhibitor database. The primary end point was all-cause mortality obtained using social security death index. After a mean follow-up of 3+/-0.9 years, the mortality rate in the bare metal stents group was 12.8% compared with 7.1% in the drug-eluting stents group [adjusted P value=0.19; hazard ratio (HR) for bare metal stents group compared with drug-eluting stents group for death=1.4; 95% confidence interval (CI): 0.8-2.4]. In a subgroup analysis, patients presenting with acute coronary syndrome had a higher mortality when treated with bare metal stents compared with drug-eluting stents (17.1 vs. 6.3%, P=0.022; HR=2.2; 95% CI: 1.1-4.4). Patients with chronic kidney disease (all patients with creatinine >1.5 mg/dl) also had a higher mortality with bare metal stents compared with drug-eluting stents (36.7 vs. 20.4%, P=0.044; HR=2.3; 95% CI: 1.02-5.2). Drug-eluting stents seem to be safe in African-Americans and may improve survival in certain subgroups such as patients with acute coronary syndromes and chronic kidney disease.

  9. Numerical investigations of the mechanical properties of braided vascular stents.

    Science.gov (United States)

    Fu, Wenyu; Xia, Qixiao; Yan, Ruobing; Qiao, Aike

    2018-01-01

    Braided stents, such as Pipeline Embolization Device (PED; ev3 Neurovascular, Irvine, CA, USA), are commonly used to treat cerebral aneurysms. However, little information is available on the compression and bending characteristics of such stents. This paper investigates how geometrical parameters of braided stents influence their radial compression and bending characteristics. Six groups of braided stent models with different braiding angles, numbers of wires and wire diameters are constructed. Parametric analyses of these models are conducted using Abaqus/Explicit software. The numerical results of a finite element analysis are validated by comparison with data of theoretical analysis. The results show that the radial stiffness is not uniform along the longitudinal direction of the stent. When the braiding angle increases from 30° to 75°, the minimum radial deformation decreases from 0.85 mm to 0.0325 mm (at a pressure of 500 Pa, for 24 braided wires). When the wire diameter increases from 0.026 mm to 0.052 mm, the minimum radial deformation decreases from 0.65 mm to 0.055 mm (at a pressure of 500 Pa and a braiding angle of 60°, for 24 braided wires). Frictions don't affect stent diameter and its axial length when braided stent is crimping, but the friction must be considered when it is related to the radial pressure required for compression the braided stent. Compared with commonly used intracranial stents, a braided stent with geometrical parameters close to PED stent has a smaller radial stiffness but a considerably greater longitudinal flexibility. The results of this analysis of braided stents can help in the design and selection of flow diverter stents for clinical treatment of cerebral aneurysms.

  10. Oversizing and Restenosis with Self-Expanding Stents in Iliofemoral Arteries

    International Nuclear Information System (INIS)

    Saguner, Ardan M.; Traupe, Tobias; Räber, Lorenz; Hess, Nina; Banz, Yara; Saguner, Arhan R.; Diehm, Nicolas; Hess, Otto M.

    2012-01-01

    Purpose: Uncoated self-expanding nitinol stents (NS) are commonly oversized in peripheral arteries. In current practice, 1-mm oversizing is recommended. Yet, oversizing of NS may be associated with increased restenosis. To provide further evidence, NS were implanted in porcine iliofemoral arteries with a stent-to-artery-ratio between 1.0 and 2.3. Besides conventional uncoated NS, a novel self-expanding NS with an antiproliferative titanium-nitride-oxide (TiNOX) coating was tested for safety and efficacy. Methods: Ten uncoated NS and six TiNOX-coated NS (5–6 mm) were implanted randomly in the iliofemoral artery of six mini-pigs. After implantation, quantitative angiography (QA) was performed for calculation of artery and minimal luminal diameter. Follow-up was performed by QA and histomorphometry after 5 months. Results: Stent migration, stent fracture, or thrombus formation were not observed. All stents were patent at follow-up. Based on the location of the stent (iliac/femoral) and the stent-to-artery-ratio, stent segments were divided into “normal-sized” (stent-to-artery-ratio < 1.4, n = 12) and “oversized” (stent-to-artery-ratio ≥ 1.4, n = 9). All stent segments expanded to their near nominal diameter during follow-up. Normal-sized stent segments increased their diameter by 6% and oversized segments by 29%. A significant correlation between oversizing and restenosis by both angiography and histomorphometry was observed. Restenosis rates were similar for uncoated NS and TiNOX-coated NS. Conclusions: TiNOX-coated NS are as safe and effective as uncoated NS in the porcine iliofemoral artery. All stents further expand to near their nominal diameter during follow-up. Oversizing is linearly and positively correlated with neointimal proliferation and restenosis, which may not be reduced by TiNOX-coating.

  11. [Magnetic resonance compatibility research for coronary mental stents].

    Science.gov (United States)

    Wang, Ying; Liu, Li; Wang, Shuo; Shang, Ruyao; Wang, Chunren

    2015-01-01

    The objective of this article is to research magnetic resonance compatibility for coronary mental stents, and to evaluate the magnetic resonance compatibility based on laboratory testing results. Coronary stents magnetic resonance compatibility test includes magnetically induced displacement force test, magnetically induced torque test, radio frequency induced heating and evaluation of MR image. By magnetic displacement force and torque values, temperature, and image distortion values to determine metal coronary stent demagnetization effect. The methods can be applied to test magnetic resonance compatibility for coronary mental stents and evaluate its demagnetization effect.

  12. Treatment of hilar cholangiocarcinoma with inserting biliary double stents

    International Nuclear Information System (INIS)

    Jia Guangzhi; Zhang Zidong; Wang Xuejing; Yin Hua; Li Jianming

    2004-01-01

    Objective: To investigate the inserting technique of biliary double stents in treating hilar cholangiocarcinoma. Methods: 6 patients with hilar cholangiocarcinoma (Bismuth IV) were treated by percutaneous transhepatic insertion of biliary stents. Double stents were inserted in each patient. Different inserting methods were adopted according to the branch angles formed by left and right hepatic ducts. Results: The jaundice of all patients alleviated or disappeared obviously after stent implantation. The average difference between post-and pre-operation in the serum total bilirubin level was (104 ± 29) μmol/L (P<0.01). Stent obstruction was found in 2 cases after 4 and 6 months respectively. Conclusion: Double stents implantation is effective for the treatment of hilar cholangiocarcinoma. Beware of the angulation between main hepatic duct and adopting different inserting methods. (authors)

  13. Post-biliary sphincterotomy bleeding despite covered metallic stent deployment

    Directory of Open Access Journals (Sweden)

    Gianfranco Donatelli

    2016-05-01

    Full Text Available Objectives: Several endoscopic techniques have been proposed for the management of post-sphincterotomy bleeding. Lately, self-expandable metal stents deployment has gained popularity especially as a rescue therapy when other endoscopic techniques fail. Methods-results: We report the case report of a massive post-sphincterotomy bleeding in a patient with a self-expandable metal stent in the biliary tree. Despite the presence of a correctly positioned self-expandable metal stent, a new endoscopic session was required to control the bleeding. Conclusions: Self-expandable metal stent may be useful to manage post-endoscopic sphincterotomy bleeding. However, up to now there is no specifically designed self-expandable metal stent for such complication. Large new designed self-expandable metal stent may be a useful tool for biliary endoscopist.

  14. Gastric and Duodenal Stents: Follow-Up and Complications

    International Nuclear Information System (INIS)

    Pinto Pabon, Isabel Teresa; Paul Diaz, Laura; Ruiz de Adana, Juan Carlos; Lopez Herrero, Julio

    2001-01-01

    Purpose: To assess the efficacy of self-expanding metallic stents in treating inoperable gastric and duodenal stenoses during follow-up and to evaluate the complications encountered.Methods: A total of 31 patients suffering from gastroduodenal obstruction (29 malignant, 2 benign) were treated with a self-expanding metallic stent (Wallstent). In 24 cases insertion was by the peroral route, in seven cases via gastrostomy.Results: All the strictures were successfully negotiated under fluoroscopic guidance without having to resort to endoscopy. A total of 27 patients (87%) were able to resume a regular diet, a soft diet, or a liquid diet orally. Complications included one case of stent malpositioning, one case of leakage of ascitic fluid through the gastrostomy orifice, one case of perforation and fistula to the biliary tree, and two cases of hematemesis. In two patients (6%) additional stents were implanted to improve patency. In all patients follow-up was maintained until death. Recurrence of symptoms immediately before death occurred in seven cases (23%). Mean survival time of patients was 13.3 weeks (SE ± 4.6).Conclusions: The deployment of gastroduodenal stents resulted in good palliation of inoperable gastric and duodenal stenoses. Certain technical aspects, e.g., adaptation of stents to bowel morphology, is critical to proper stent function and avoidance of complications

  15. Successful Treatment of Bronchoesophageal Fistula With Esophageal and Bronchial Stenting

    Directory of Open Access Journals (Sweden)

    Cheng-Yi Wang

    2011-04-01

    Full Text Available Bronchoesophageal fistula is reported in 5-10% of patients with esophageal cancer. In most of these cases, the insertion of a single stent, either a tracheobronchial or an esophageal stent, is sufficient to seal off the fistula. In this case we describe a 67-year-old man with esophageal cancer and complications of bronchoesophageal fistula, which resulted in repeated pneumonia and acute respiratory failure. Initially, two expandable metallic membranous esophageal stents were placed to cover the fistula. However, the esophageal stent failed to stop the air leak and dislodged into the stomach. Thereafter, a bronchial stent was placed at the right intermediate bronchus and successfully stopped the air leak. The patient was then weaned from the ventilator 1 week after the insertion of a bronchial stent. In conclusion, stenting in both the esophagus and airways should be considered when both are severely invaded by malignancy, when the airway is compressed, or when the fistula is insufficiently sealed by an esophageal stent.

  16. A non-uniform expansion mechanical safety model of the stent.

    Science.gov (United States)

    Yang, J; Huang, N; Du, Q

    2009-01-01

    Stents have a serial unstable structure that readily leads to non-uniform expansion. Non-uniform expansion in turn creates a stent safety problem. We explain how a stent may be simplified to a serial unstable structure, and present a method to calculate the non-uniform expansion of the stent on the basis of the serial unstable structure. We propose a safety criterion based on the expansion displacement instead of the strain, and explain that the parameter Rd, the ratio of the maximum displacement of the elements to normal displacement, is meaningful to assess the safety level of the stent. We also examine how laser cutting influences non-uniform expansion. The examples illustrate how to calculate the parameter Rd to assess non-uniform expansion of the stent, and demonstrate how the laser cutting offset and strengthening coefficient of the material influence the stent expansion behaviour. The methods are valuable for assessing stent safety due to non-uniform expansion.

  17. Covered Metallic Stents With an Anti-Migration Design vs. Uncovered Stents for the Palliation of Malignant Gastric Outlet Obstruction: A Multicenter, Randomized Trial

    Science.gov (United States)

    Lee, Hyuk; Min, Byung-Hoon; Lee, Jeong Hoon; Shin, Cheol Min; Kim, Younjoo; Chung, Hyunsoo; Lee, Sang Hyub

    2015-01-01

    OBJECTIVES: Previous studies reported comparable stent patency between covered self-expandable metallic stents (SEMS) and uncovered SEMS (UCS) for palliation of malignant gastric outlet obstruction (GOO). The aim of this study was to evaluate the efficacy and safety of the newly developed WAVE-covered SEMS (WCS), which has an anti-migration design, compared with UCS in gastric cancer patients with symptomatic GOO. METHODS: A total of 102 inoperable gastric cancer patients with symptomatic GOO were prospectively enrolled from five referral centers and randomized to undergo UCS or WCS placement. Stent patency and recurrence of obstructive symptoms were assessed at 8 weeks and 16 weeks after stent placement. RESULTS: At the 8-week follow-up, both stent patency rates (72.5% vs. 62.7%) and re-intervention rates (19.6% vs. 19.6%) were comparable between the WCS and the UCS groups. Both stent stenosis (2.4% vs. 8.1%) and migration rates (9.5% vs. 5.4%) were comparable between WCS and UCS groups. At the 16-week follow-up, however, the WCS group had a significantly higher stent patency rate than the UCS group (68.6% vs. 41.2%). Re-intervention rates in the WCS and UCS groups were 23.5% and 39.2%, respectively. Compared with the UCS group, the WCS group had a significantly lower stent restenosis rate (7.1% vs. 37.8%) and a comparable migration rate (9.5% vs. 5.4%). Overall stent patency was significantly longer in the WCS group than in the UCS group. No stent-associated significant adverse events occurred in either the WCS or UCS groups. In the multivariate analysis, WCS placement and chemotherapy were identified as independent predictors of 16-week stent patency. CONCLUSIONS: WCS group showed comparable migration rate and significantly more durable long-term stent patency compared with UCS group for the palliation of GOO in patients with inoperable gastric cancer. PMID:26372507

  18. Treatment of carotid artery aneurysms with covered stents; Aneurysmabehandlung der Arteria carotis interna mit gecoverten Stents

    Energy Technology Data Exchange (ETDEWEB)

    Rohr, A.; Alfke, K.; Doerner, L.; Jansen, O. [UKSH Kiel (Germany). Neurochirurgie Neuroradiologie; Bartsch, T.; Stingele, R. [UKSH Kiel (Germany). Neurologie

    2007-10-15

    Purpose: Evaluation of the use of covered stents in treating pseudoaneurysms of the cervical and intracranial/extradural carotid artery and determination of the periprocedural and short- to mid-term complication rate. Materials and Methods: 8 patients with 9 spontaneous dissecting aneurysms of the cervical carotid artery - 5 of which were symptomatic - plus one patient with ofthalmoplegia due to an aneurysm of the cavernous carotid artery were studied. While the latter was treated with a PTFE-covered balloon-mounted stainless steel stent (Jostent/Graftmaster), a self-expanding PTFE-covered Nitonol Stent (Symbiot) was used in all other cases. Intervention was performed with local anesthesia. Aspirin and Clopidogrel were both used as antiplatelet drugs. Clinical signs and symptoms and vascular imaging with DS, MR, CT angiography and ultrasound were recorded during patient follow-up, with a mean follow-up period of 14.6 months (4 - 30). Results: We were able to treat 8 out of 10 aneurysms (80 %) using covered stents. The aneurysms were immediately occluded and the associated stenoses of the parent vessel were eliminated. No clinically relevant complications occurred during the procedure or in the follow-up interval. In two cases, elongation of the carotid artery prevented the stent from being positioned over the aneurysm neck. These cases were shown to be stable with the use of antiplatelet drugs. Conclusion: Covered stents can be used in the treatment of pseudoaneurysms of the carotid artery as an alternative to long-term antithrombotic medication or surgery. In our study treatment was effective (80 %) and free of complications in the short- and mid-term follow-up. Possible indications, technique and the use of imaging modalities for patient follow-up are discussed. (orig.)

  19. Risk factors for in-stent restenosis of vertebral artery origin after stent implantation: a Meta-analysis

    Directory of Open Access Journals (Sweden)

    Fang-fang HAO

    2018-01-01

    Full Text Available Objective To systematically review the risk factors for in-stent restenosis (ISR of vertebral artery origin after sent implantation to provide theoretical foundation for clinical prevention and treatment. Methods Taking vertebral artery, vertebrobasilar insufficiency, stents, drug-eluting stents, self expandable metallic stents in English and Chinese as key words, retrospective clinical studies about risk factors for ISR of vertebral artery origin were searched by using PubMed, EMBASE/SCOPUS, Cochrane Library, China Biology Medicine (CBM, China National Knowledge Infrastructure (CNKI, Wanfang Data and VIP database from January 1, 1966 to March 30, 2017. Quality assessment and Meta-analysis were made by using Newcastle-Ottawa Scale (NOS and Stata 12.0 software. Results The research enrolled 3468 articles in all, from which 11 studies were chosen after excluding duplicates and those not meeting the inclusion criteria. A total number of 1352 patients were divided into ISR group (N = 440 and non-ISR group (N = 912. The ISR incidence rate of smokers was significantly higher than non-smokers (OR = 2.179, 95%CI: 1.373-3.458; P = 0.001. The differences of bare metal stents (BMS utilization rate (OR = 2.072, 95% CI: 1.560-2.753; P = 0.000 and drug-eluting stents (DES utilization rate (OR = 0.483, 95% CI: 0.363-0.641; P = 0.000 between ISR group and non-ISR group were statistically significant. Conclusions Smoking and using BMS are risk factors for ISR of vertebral artery origin, and using DES is protective factor. Due to limited study quality, more high-quality studies are needed to verify this conclusion. DOI: 10.3969/j.issn.1672-6731.2017.12.004

  20. Association of localized hypersensitivity and in-stent neoatherosclerosis with the very late drug-eluting stent thrombosis.

    Directory of Open Access Journals (Sweden)

    Kyohei Yamaji

    Full Text Available Localized hypersensitivity reaction, delayed arterial healing, and neoatherosclerosis inside the stent have been suggested as the underlying pathologic mechanisms of very late stent thrombosis (VLST of drug-eluting stent (DES. The present study sought to explore the prevalence of inflammatory cell infiltrates and evidence for fragments of atherosclerotic plaques in the aspirated thrombi in patients with DES VLST.From April 2004 to September 2012, 48 patients with stent thrombosis (ST of DES underwent thrombus aspiration with retrieved material sufficient for the histopathologic analysis; early ST (EST, within 30 days: N = 17, late ST (LST, between 31 and 365 days: N = 7, and very late ST (VLST, >1 year: N = 24. Eosinophil fraction in the aspirated thrombi was significantly higher in patients with VLST (8.2±5.7% as compared with those with EST (4.3±3.0% and LST (5.5±3.8% (P = 0.03. Eosinophil fraction in the aspirated thrombi was significantly higher in 12 VLST patients with angiographic peri-stent contrast staining (PSS and/or incomplete stent apposition (ISA by intravascular ultrasound than in 12 VLST patients without PSS or ISA (10.6±6.1% versus 5.8±4.1%, P = 0.03. Evidences for fragments of atherosclerotic plaques in the aspirated thrombi were observed only in 3 (13% out of 24 patients with DES VLST.Eosinophil fraction in the aspirated thrombi was significantly higher in patients with DES VLST as compared with those with EST and LST. Evidences for fragments of atherosclerotic plaques were relatively uncommon in patients with DES VLST.

  1. High-Resolution CT and Angiographic Evaluation of NexStent Wall Adaptation

    International Nuclear Information System (INIS)

    Nemes, Balazs; Lukacs, Levente; Balazs, Gyoergy; Dosa, Edit; Berczi, Viktor; Huettl, Kalman

    2009-01-01

    Carotid stenting is a minimally invasive treatment for extracranial carotid artery stenosis. Stent design may affect technical success and complications in a certain subgroup of patients. We examined the wall adaptability of a new closed-cell carotid stent (NexStent), which has a unique rolled sheet design. Forty-one patients had 42 carotid arteries treated with angioplasty and stenting for internal carotid artery stenosis. The mean patient age was 65 ± 10 years. All patients underwent high-resolution computed tomographic angiography after the stent implantation. Data analysis included pre- and postprocedural stenosis, procedure complications, plaque calcification, and stent apposition. We reviewed the angiographic and computed tomographic images for plaque coverage and stent expansion. All procedures were technically successful. Mean stenosis was reduced from 84 ± 8% before the procedure to 15.7 ± 7% after stenting. Two patients experienced transient ischemic attack; one patient had bradycardia and hypotension. Stent induced kinking was observed in one case. Good plaque coverage and proper overlapping of the rolled sheet was achieved in all cases. There was weak correlation between the residual stenosis and the amount of calcification. The stent provides adequate expansion and adaptation to the tapering anatomy of the bifurcation.

  2. Stent implantation influence wall shear stress evolution

    Science.gov (United States)

    Bernad, S. I.; Totorean, A. F.; Bosioc, A. I.; Petre, I.; Bernad, E. S.

    2016-06-01

    Local hemodynamic factors are known affect the natural history of the restenosis critically after coronary stenting of atherosclerosis. Stent-induced flows disturbance magnitude dependent directly on the strut design. The impact of flow alterations around struts vary as the strut geometrical parameters change. Our results provide data regarding the hemodynamic parameters for the blood flow in both stenosed and stented coronary artery under physiological conditions, namely wall shear stress and pressure drop.

  3. Influence of stent design and use of protection devices on outcome of carotid artery stenting: a pooled analysis of individual patient data.

    Science.gov (United States)

    Wodarg, Fritz; Turner, Elisabeth L; Dobson, Joanna; Ringleb, Peter A; Mali, Willem P; Fraedrich, Gustav; Chatellier, Gilles; Bequemin, Jean-Pierre; Brown, Martin M; Algra, Ale; Mas, Jean-Louis; Jansen, Olav; Bonati, Leo H

    2018-04-19

    Carotid artery stenting is an alternative to endarterectomy for the treatment of symptomatic carotid stenosis but was associated with a higher risk of procedural stroke or death in randomized controlled trials (RCTs). Technical aspects of treatment may partly explain these results. The purpose of this analysis was to investigate the influence of technical aspects such as stent design or the use of protection devices, as well as clinical variables, on procedural risk. We pooled data of 1557 individual patients receiving stent treatment in three large RCTs comparing stenting versus endarterectomy for symptomatic carotid stenosis. The primary outcome event was any procedural stroke or death occurring within 30 days after stenting. Procedural stroke or death occurred significantly more often with the use of open-cell stents (61/595 patients, 10.3%) than with closed-cell stents (58/962 patients, 6.0%; RR 1.76; 95% CI 1.23 to 2.52; P=0.002). Procedural stroke or death occurred in 76/950 patients (8.0%) treated with protection devices (predominantly distal filters) and in 43/607 (7.1%) treated without protection devices (RR 1.10; 95% CI 0.71 to 1.70; P=0.67). Clinical variables predicting the primary outcome event were age, severity of the qualifying event, history of prior stroke, and level of disability at baseline. The effect of stent design remained similar after adjustment for these variables. In symptomatic carotid stenosis, the use of stents with a closed-cell design is independently associated with a lower risk of procedural stroke or death compared with open-cell stents. Filter-type protection devices do not appear to reduce procedural risk. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  4. Comparison of Enterprise with Neuroform stent-assisted coiling of intracranial aneurysms.

    Science.gov (United States)

    Kadkhodayan, Yasha; Rhodes, Nicholas; Blackburn, Spiros; Derdeyn, Colin P; Cross, DeWitte T; Moran, Christopher J

    2013-04-01

    The Enterprise stent is the first closed-cell stent designed to treat wide-necked intracranial aneurysms. Advantages of the design can include improvement in keeping coils within an aneurysm and the ability of the stent to be recaptured. We compared the technical and clinical complications of the Enterprise stent with the open-cell Neuroform stent, its primary alternative. Patients undergoing Enterprise and Neuroform stent-assisted aneurysm coiling were enrolled in prospective registries starting in March 2007 and February 2003, respectively. All consecutive patients through December 2011 were included. Deployment success and difficulty, stent movement and misplacement, and procedural complications were compared. Enterprise deployment success was high (108 of 115 attempts, 93.9%) with 102 aneurysms receiving a stent compared with Neuroform (173 of 214 attempts, 80.8%, p = 0.001) with 163 aneurysms. Enterprise was easier to deploy (1.7% vs 15.9% difficult deployment, p Enterprise stent (8.7% vs 1.4%, p = 0.0021). The Enterprise stent enabled treatment of 10 additional aneurysms that could not be treated with Neuroform and had a higher rate of immediate aneurysm occlusion (87.3% vs 73.0%, p = 0.0058). Enterprise was easier to deploy and enabled treatment of additional aneurysms; however, there were more thromboembolic complications. On the basis of these findings, we prefer to use the Neuroform stent first and rely on the Enterprise stent as an easy-to-deliver backup for stent-assisted coiling.

  5. Treatment of esophagopleural fistulas using covered retrievable expandable metallic stents.

    Science.gov (United States)

    Kim, Tae-Hyung; Shin, Ji Hoon; Kim, Kyung Rae; Park, Jung-Hoon; Kim, Jin Hyoung; Song, Ho-Young

    2014-04-01

    To evaluate the clinical efficacy of placement of covered retrievable expandable metallic stents for esophagopleural fistulas (EPFs). During the period 1997-2013, nine patients with EPF were treated using covered retrievable expandable metallic stents. The underlying causes of EPF were esophageal carcinoma (n = 6), lung cancer (n = 2), and postoperative empyema for Boerhaave syndrome (n = 1). Technical success was achieved in eight patients (88.9%). In one patient, incomplete EPF closure was due to incomplete stent expansion. Clinical success, defined as complete EPF closure within 7 days, was achieved in five patients (55.6%). Overall fistula persistence (n = 1) or reopening (n = 4) occurred in five patients (55.6%) 0-15 days after stent placement. The causes of reopening were due to the gap between the stent and the esophagus (n = 3) or stent migration (n = 1). For fistula persistence or reopening, additional interventional management, such as gastrostomy, stent removal, or stent reinsertion, was performed. Stent migration occurred as a complication in one patient with EPF from a benign cause secondary to postoperative empyema. In the eight patients who died during the follow-up period, the mean and median survival times were 78.8 days and 46 days, respectively. Placement of a covered expandable metallic esophageal stent for the palliative treatment of EPF is technically feasible, although the rate of clinical success was poor secondary to fistula persistence or reopening. Fistula reopening was caused by the gap between the stent and the esophagus or by stent migration, and additional interventional treatment was useful to ensure enteral nutritional support. Copyright © 2014 SIR. Published by Elsevier Inc. All rights reserved.

  6. Biodegradable stents in benign stenosis of the esophagus

    International Nuclear Information System (INIS)

    Manova, G.

    2013-01-01

    Full text: Introduction: Benign stenosis of the esophagus can be postcorrosion peptic or postoperative. The treatment is difficult and traditionally consists of multiple dilatations. In refractory stenosis the placement of metal self-expanding stents is disputed because requiring their subsequent removal. New experience for therapeutic decision is self- degradable stents. Manipulation is a single and not requires their removal. What you will learn: Patients indicated for the treatment with self- degradable stents are with benign stenosis not suitable for balloon dilatation or bougienage dilation. The main groups are those with postcorrosion stenosis, peptic stenosis due to untreated gastroesophageal reflux disease with different prescription as well as post-surgical and post-radiation stenosis. Self-expanding stents made by monofilament polymer of polydioxanone, whose integrity and radial force remain 6-8 weeks depending on the gastric pH are used. Stents are applied in hard guide placed in the stenosis through the working channel of gastroscopy, and they are released under X-ray control. Putting is preceded by balloon dilatation due to the large diameter of the mounted stent. During the manipulations, several difficulties are encountered, which are missing in self-expanding metal stents. Discussion: Short-term results are satisfactory - Dysphagia in the patients is overcome and they recover their normal diet. The patients reported no pain. The control inspection of the 1st month showed partial degradation of the stents. On 3rd month it is set the complete degradation. Term follow-up shows resumption of dysphagia. Conclusion: Good short-term results make the use of self-degradable stents possible alternative for the treatment of the esophagus refractory stenosis. Long-term results are contradictory, still missing long enough randomized studies on this topic

  7. Peri-stent aneurysm formation following a stent implant for stenotic intracranial vertebral artery dissection: a technical report of two cases successfully treated with coil embolization.

    Science.gov (United States)

    Ishimaru, Hideki; Nakashima, Kazuaki; Takahata, Hideaki; Matsuoka, Yohjiro

    2013-02-01

    Although stenting for stenotic vertebral artery dissection (VAD) improves compromised blood flow, subsequent peri-stent aneurysm (PSA) formation is not well-known. We report two cases with PSA successfully treated with coil embolization. Three patients with stenotic intracranial VAD underwent endovascular angioplasty at our institution because they had acute infarction in posterior circulation territory and clinical evidence of hemodynamic insufficiency. In two of three patients balloon angioplasty at first session failed to relieve the stenosis, and a coronary stent was implanted. Angiography immediately after stenting showed no abnormality in case 1 and minimal slit-like projection at proximal portion of the stent in case 2. Angiography obtained 16 months after the stenting revealed PSA in case 1. In case 2, angiography performed 3 months later showed that the projection at proximal portion enlarged and formed an aneurysm outside the stent. Because follow-up angiographies showed growth of the aneurysm in both cases, endovascular aneurysmal embolization was performed. We advanced a microcatheter into the aneurysm through the strut of existing stent and delivered detachable coils into the aneurysm lumen successfully in both cases. The post-procedural course was uneventful, and complete obliteration of aneurysm was confirmed on angiography in both cases. Stenting for stenotic intracranial VAD may result in delayed PSA; therefore, follow-up angiographies would be necessary after stenting for stenotic intracranial arterial dissection. Coil embolization through the stent strut would be a solution for enlarging PSA.

  8. Evaluation of Polyurethane Nasolacrimal Duct Stents: In Vivo Studies in New Zealand Rabbits

    International Nuclear Information System (INIS)

    Wilhelm, K.E.; Grabolle, B.; Urbach, H.; Tolba, R.; Schild, H.; Paulsen, F.

    2006-01-01

    The purpose of this study was to evaluate the radiographic and biological effects of different polyurethane nasolacrimal duct stents in an animal model. Fifteen polyurethane nasolacrimal duct stents (n = 5 mushroom-type stents, n = 5 newly designed S-shaped TearLeader stents without hydrophilic coating, and n = 5 S-shaped TearLeader stents with hydrophilic coating) were implanted in the nasolacrimal ducts of eight unaffected New Zealand rabbits. One nasolacrimal system served as control. Clinical and radiographic follow-up was performed at 1-, 2-, and 4-week intervals, then after a 3-month interval, after which the animals were euthanized. All stents were implanted without major periprocedural complications. The stents proved to be patent by the end of the procedure. During follow-up, all mushroom-type stents were occluded at 4 weeks. None of these stents opened to forced irrigation. Clinically, all rabbits demonstrated severe dacryocystitis. Three out of five TearLeader stents without hydrophilic coating were blocked at 4 weeks; one out of five was open to irrigation. Best results were observed in the stent group with hydrophilic coating. Follow-up dacryocystography demonstrated patent stents in nasolacrimal ducts of all animals after 4 weeks. In only one of five cases, the coated stent became partially occluded after 2 months. These animals were free of clinical symptoms. After 3 months, at least three out of five stents still opened to forced irrigation and only one stent was completely blocked. Dislocation of the stents was not observed. Refinement of the stent surface and stent design improves the results of nasolacrimal duct stenting in this animal model. Implantation of hydrophilic-coated S-shaped stents is highly superior to conventional mushroom-type stents and noncoated stent types. Hydrophilic coating seems to prevent foreign-body reactions, resulting in maximized stent patency

  9. 3D Stereoscopic Visualization of Fenestrated Stent Grafts

    International Nuclear Information System (INIS)

    Sun Zhonghua; Squelch, Andrew; Bartlett, Andrew; Cunningham, Kylie; Lawrence-Brown, Michael

    2009-01-01

    The purpose of this study was to present a technique of stereoscopic visualization in the evaluation of patients with abdominal aortic aneurysm treated with fenestrated stent grafts compared with conventional 2D visualizations. Two patients with abdominal aortic aneurysm undergoing fenestrated stent grafting were selected for inclusion in the study. Conventional 2D views including axial, multiplanar reformation, maximum-intensity projection, and volume rendering and 3D stereoscopic visualizations were assessed by two experienced reviewers independently with regard to the treatment outcomes of fenestrated repair. Interobserver agreement was assessed with Kendall's W statistic. Multiplanar reformation and maximum-intensity projection visualizations were scored the highest in the evaluation of parameters related to the fenestrated stent grafting, while 3D stereoscopic visualization was scored as valuable in the evaluation of appearance (any distortions) of the fenestrated stent. Volume rendering was found to play a limited role in the follow-up of fenestrated stent grafting. 3D stereoscopic visualization adds additional information that assists endovascular specialists to identify any distortions of the fenestrated stents when compared with 2D visualizations.

  10. Comparison of devices used for stent-assisted coiling of intracranial aneurysms.

    Directory of Open Access Journals (Sweden)

    Benjamin Izar

    Full Text Available INTRODUCTION: Two self-expandable stents, the Neuroform and the Enterprise stent, are widely used for stent-assisted coiling (SAC of complex shaped intracranial aneurysms. However, comparative knowledge about technical feasibility, peri- and post-procedural morbidity and mortality, packing densities as well as follow-up data is limited. MATERIAL AND METHODS: We conducted a retrospective study to investigate differences in aneurysms stented with the Enterprise or Neuroform stents. Angiographic follow-up (mean 19.42 months was available in 72.6% (61/84 of aneurysms treated with stent-assisted coiling. We further sought to compare stent-assisted coiling to a matched patient population with aneurysms treated by conventional coil embolization. RESULTS: The stenting success rate of the Enterprise was higher compared to the Neuroform stent (46/48 and 42/51, respectively. In 5 of 9 cases in which the Neuroform stent was not navigable to the landing zone, we successfully deployed an Enterprise stent instead. Eventually, 42 aneurysms were coiled after stenting in each group. We observed no significant differences in peri-procedural complication rate, post-procedural hospital stay, packing density, recurrence rate or number of in-stent stenosis. Strikingly, 36.1% of followed aneurysms in the SAC group showed progressive occlusion on angiographic follow-up imaging. The packing density was significantly higher in aneurysms treated by SAC as compared to conventionally coiled aneurysms, while recanalization rate was significantly lower in the SAC group. CONCLUSION: The procedural success rate is higher using the Enterprise, but otherwise both stents exhibited similar characteristics. Lower recurrence frequency and complication rates comparable to conventional coil embolization emphasize the importance of stent-assisted coiling in the treatment of complex aneurysms. Progressive occlusion on angiographic follow-up was a distinct and frequent observation in the

  11. Type D personality predicts death or myocardial infarction after bare metal stent or sirolimus-eluting stent implantation

    DEFF Research Database (Denmark)

    Pedersen, Susanne S.; Lemos, Pedro A; van Vooren, Priya R

    2004-01-01

    We investigated the effect of Type D personality on the occurrence of adverse events at nine months in patients with ischemic heart disease (IHD) after percutaneous coronary intervention (PCI) with sirolimus-eluting stents (SESs) or bare stents. Type D patients experience increased negative...

  12. Outcomes of Temporary Partially Covered Stent Placement for Benign Tracheobronchial Stenosis

    International Nuclear Information System (INIS)

    Ma, Ji; Han, Xinwei; Wu, Gang; Jiao, Dechao; Ren, Kewei; Bi, Yonghua

    2016-01-01

    PurposeTo evaluate the intermediate outcomes of temporary partially covered tracheobronchial stenting in patients with benign tracheobronchial stenosis.Materials and MethodsWe conducted a retrospective study of patients with benign tracheobronchial stenosis who underwent stent placement. All stents were removed approximately 3 months after placement. Respiratory function was assessed using the visual analogue scale (VAS) and Karnofsky performance status scale (KPS) before and after stent placement. The lumen diameters of the stenotic lesions were measured using chest computed tomography (CT) and compared between before stent placement and after stent removal.ResultsA total of 51 stents were successfully placed in consecutive 51 patients with benign tracheobronchial stenosis. No serious complications occurred. The mean VAS and KPS scores significantly improved after stent removal (6.291 ± 0.495 and 25.352 ± 10.533, respectively) compared with those before stent placement (1.493 ± 0.504 and 60.140 ± 16.344, respectively; P   0.05).ConclusionTemporary partially covered stenting may be a safe and effective treatment for benign tracheobronchial stenosis.

  13. Outcomes of Temporary Partially Covered Stent Placement for Benign Tracheobronchial Stenosis.

    Science.gov (United States)

    Ma, Ji; Han, Xinwei; Wu, Gang; Jiao, Dechao; Ren, Kewei; Bi, Yonghua

    2016-08-01

    To evaluate the intermediate outcomes of temporary partially covered tracheobronchial stenting in patients with benign tracheobronchial stenosis. We conducted a retrospective study of patients with benign tracheobronchial stenosis who underwent stent placement. All stents were removed approximately 3 months after placement. Respiratory function was assessed using the visual analogue scale (VAS) and Karnofsky performance status scale (KPS) before and after stent placement. The lumen diameters of the stenotic lesions were measured using chest computed tomography (CT) and compared between before stent placement and after stent removal. A total of 51 stents were successfully placed in consecutive 51 patients with benign tracheobronchial stenosis. No serious complications occurred. The mean VAS and KPS scores significantly improved after stent removal (6.291 ± 0.495 and 25.352 ± 10.533, respectively) compared with those before stent placement (1.493 ± 0.504 and 60.140 ± 16.344, respectively; P  0.05). Temporary partially covered stenting may be a safe and effective treatment for benign tracheobronchial stenosis.

  14. Stented Vessels: A Challenge for Histological Preparation and Microscopy

    Directory of Open Access Journals (Sweden)

    Andrea Nolte

    2013-06-01

    Full Text Available Objective: The first procedure to treat blocked coronary arteries was coronary artery bypass graft surgery. In 1977, Andreas Gruntzig introduced percutaneous transluminal coronary angioplasty (PTCA. Today, several stent systems exist ranging from bare metal stents to various drug-eluting stents. Unfortunately, our understanding of the arterial reaction to stent implantation is incomplete – primarily due to technical limitations in the histological study of stented vascular tissue. Methods: In our study, we examined different histological preparation methods based on the embedding material methacrylate. The procedure of embedding and sectioning stented porcine arteries was optimized for the specific requirements, like histochemistry, immunohistochemistry or pre-stained fluorescence. Furthermore, we used a microscopical technique described as fluorescence intensity decay shape analysis microscopy (FIDSAM to eliminate auto-fluorescence from fluorescently labeled tissue. Results: The sections were suitable for histochemical and immunohistochemical staining. Additionally, pre-labeled fluorescence in the porcine tissue was not lost by the embedding process. The evaluation of arterial cross sections with FIDSAM technology gave new, very important insights into the examination possibilities of fluorescently labeled tissue. Conclusions: Future studies of the vascular response to a variety of new stent materials will provide important clues to the pathogenesis resulting in restenosis and occlusion of stents. [J Interdiscipl Histopathol 2013; 1(3.000: 104-112

  15. Reproducibility of haemodynamical simulations in a subject-specific stented aneurysm model--a report on the Virtual Intracranial Stenting Challenge 2007.

    Science.gov (United States)

    Radaelli, A G; Augsburger, L; Cebral, J R; Ohta, M; Rüfenacht, D A; Balossino, R; Benndorf, G; Hose, D R; Marzo, A; Metcalfe, R; Mortier, P; Mut, F; Reymond, P; Socci, L; Verhegghe, B; Frangi, A F

    2008-07-19

    This paper presents the results of the Virtual Intracranial Stenting Challenge (VISC) 2007, an international initiative whose aim was to establish the reproducibility of state-of-the-art haemodynamical simulation techniques in subject-specific stented models of intracranial aneurysms (IAs). IAs are pathological dilatations of the cerebral artery walls, which are associated with high mortality and morbidity rates due to subarachnoid haemorrhage following rupture. The deployment of a stent as flow diverter has recently been indicated as a promising treatment option, which has the potential to protect the aneurysm by reducing the action of haemodynamical forces and facilitating aneurysm thrombosis. The direct assessment of changes in aneurysm haemodynamics after stent deployment is hampered by limitations in existing imaging techniques and currently requires resorting to numerical simulations. Numerical simulations also have the potential to assist in the personalized selection of an optimal stent design prior to intervention. However, from the current literature it is difficult to assess the level of technological advancement and the reproducibility of haemodynamical predictions in stented patient-specific models. The VISC 2007 initiative engaged in the development of a multicentre-controlled benchmark to analyse differences induced by diverse grid generation and computational fluid dynamics (CFD) technologies. The challenge also represented an opportunity to provide a survey of available technologies currently adopted by international teams from both academic and industrial institutions for constructing computational models of stented aneurysms. The results demonstrate the ability of current strategies in consistently quantifying the performance of three commercial intracranial stents, and contribute to reinforce the confidence in haemodynamical simulation, thus taking a step forward towards the introduction of simulation tools to support diagnostics and

  16. Shrinking the Supply Chain for Implantable Coronary Stent Devices.

    Science.gov (United States)

    Moore, Sean S; O'Sullivan, Kevin J; Verdecchia, Francesco

    2016-02-01

    Stenting treatments for the management of disease in the heart, arterial and venous systems, biliary ducts, urethras, ureters, oesophageal tract and prostate have made enormous technical advances since their introduction into clinical use. The progression from metallic to polymer based bio-absorbable stents, coupled with the advances in additive manufacturing techniques, present a unique opportunity to completely re-envision the design, manufacture, and supply chain of stents. This paper looks at current stenting trends and proposes a future where the stent supply chain is condensed from ~150 days to ~20 min. The Cardiologist therefore has the opportunity to become a designer, manufacturer and user with patients receiving custom stents specific to their unique pathology that will be generated, delivered and deployed in the Cath-lab. The paper will outline this potentially revolutionary development and consider the technical challenges that will need to be overcome in order to achieve these ambitious goals. A high level overview of the generating eluting stents in situ program-GENESIS-is outlined including some early experimental work.

  17. A computational study of crimping and expansion of bioresorbable polymeric stents

    Science.gov (United States)

    Qiu, T. Y.; Song, M.; Zhao, L. G.

    2017-10-01

    This paper studied the mechanical performance of four bioresorbable PLLA stents, i.e., Absorb, Elixir, Igaki-Tamai and RevaMedical, during crimping and expansion using the finite element method. Abaqus CAE was used to create the geometrical models for the four stents. A tri-folded balloon was created using NX software. For the stents, elastic-plastic behaviour was used, with hardening implemented by considering the increase of yield stress with the plastic strain. The tri-folded balloon was treated as linear elastic. To simulate the crimping of stents, a set of 12 rigid plates were generated around the stents with a radially enforced displacement. During crimping, the stents were compressed from a diameter of 3 mm to 1.2 mm, with the maximum stress developed at both inner and outer sides of the U-bends. During expansion, the stent inner diameter increased to 3 mm at the peak pressure and then recoiled to different final diameters after balloon deflation due to different stent designs. The maximum stress was found again at the U-bends of stents. Diameter change, recoiling effect and radial strength/stiffness were also compared for the four stents to assess the effect of design variation on stent performance. The effect of loading rate on stent deformation was also simulated by considering the time-dependent plastic behaviour of polymeric material.

  18. Expandable metallic stent: experimental and clinical experience in tracheobronchial tree

    Energy Technology Data Exchange (ETDEWEB)

    Song, Ho Young; Lee, Sang Young; Chung, Jin Young; Han, Young Min; Kim, Jong Soo; Choi, Ki Chul; Hong, Ki Whan; Rhee, Yang Kun [Chonbuk National University Medical School, Jeonju (Korea, Republic of)

    1991-05-15

    To maintain or reestablish an adequate airway in a patient with tracheobronchial narrowing coming from various causes, we constructed self-expanding metallic stents the same way Gianturco did, using them in 2 patients after an experimental study with rabbits. Twenty stents (10mm in diameter fully expanded and 20mm in length) were introduced into the trachea or bronchi of 10 Newzealand rabbits (weight, 2.5-3.0kg) through a 8.5 French Teflon sheath. No difficulties were encountered in the placement of the stents. At follow-up (4-12 weeks), no stent showed migration. Three rabbits died of pneumonia or bronchial perforation. Histologically, mucosal inflammation was noted at the sites of stent placement, and stent wires were covered by proliferated epithelium with intact cilia. During the last 4 months, 2 stents were used in 2 patients, one in a patient with endobronchial tuberculosis (3.0cm in length and 1.0cm in diameter fully expanded) and the other (3.0cm in length and 1.5cm in diameter) in a patient with a subglottic mass. In both patients the stents were successfully placed. Just after the placement of the stents dyspnea subsided in both patients, and there was no mortality or morbidity. These stents seem to be effective in the treatment of tracheobronchial stenosis, tracheomalacia, and airway collapse following tracheal reconstruction.

  19. Design Investigation on Applicable Mesh Structures for Medical Stent Applications

    Science.gov (United States)

    Asano, Shoji; He, Jianmei

    2017-11-01

    In recent years, utilization of medical stents is one of effective treatments for stenosis and occlusion occurring in a living body’s lumen indispensable for maintenance of human life such as superficial femoral artery (SFA) occlusion. However, there are concerns about the occurrence of fatigue fractures caused by stress concentrations, neointimal hyperplasia and the like due to the shape structure and the manufacturing method in the conventional stents, and a stent having high strength and high flexibility is required. Therefore, in this research, applicable mesh structures for medical stents based on the design concepts of high strength, high flexibility are interested to solve various problem of conventional stent. According to the shape and dimensions of SFA occlusion therapy stent and indwelling delivery catheter, shape design of the meshed stent are performed using 3-dimensional CAD software Solid Works first. Then analytical examination on storage characteristics and compression characteristics of such mesh structure applied stent models were carried out through finite element analysis software ANSYS Workbench. Meshed stent models with higher strength and higher flexibility with integral molding are investigated analytically. It was found that the storage characteristics and compression characteristics of meshed stent modles are highly dependent on the basic mesh shapes with same surface void ratio. Trade-off relationship between flexibility and storage characteristics is found exited, it is required to provide appropriate curvatures during basic mesh shape design.

  20. Expandable metallic stent: experimental and clinical experience in tracheobronchial tree

    International Nuclear Information System (INIS)

    Song, Ho Young; Lee, Sang Young; Chung, Jin Young; Han, Young Min; Kim, Jong Soo; Choi, Ki Chul; Hong, Ki Whan; Rhee, Yang Kun

    1991-01-01

    To maintain or reestablish an adequate airway in a patient with tracheobronchial narrowing coming from various causes, we constructed self-expanding metallic stents the same way Gianturco did, using them in 2 patients after an experimental study with rabbits. Twenty stents (10mm in diameter fully expanded and 20mm in length) were introduced into the trachea or bronchi of 10 Newzealand rabbits (weight, 2.5-3.0kg) through a 8.5 French Teflon sheath. No difficulties were encountered in the placement of the stents. At follow-up (4-12 weeks), no stent showed migration. Three rabbits died of pneumonia or bronchial perforation. Histologically, mucosal inflammation was noted at the sites of stent placement, and stent wires were covered by proliferated epithelium with intact cilia. During the last 4 months, 2 stents were used in 2 patients, one in a patient with endobronchial tuberculosis (3.0cm in length and 1.0cm in diameter fully expanded) and the other (3.0cm in length and 1.5cm in diameter) in a patient with a subglottic mass. In both patients the stents were successfully placed. Just after the placement of the stents dyspnea subsided in both patients, and there was no mortality or morbidity. These stents seem to be effective in the treatment of tracheobronchial stenosis, tracheomalacia, and airway collapse following tracheal reconstruction

  1. Metallic stent and stereotactic conformal radiotherapy for hilar cholangiocarcinoma

    International Nuclear Information System (INIS)

    Li Yu; Wang Ning; Tian Qihe; Guo Zhanwen; Zhang Haibo; Song Liyan

    2005-01-01

    Objective: To evaluate the effect of metallic stent combined with stereotactic conformal radiotherapy (SCRT) for hilar cholangiocarcinoma. Methods: Fifty-four patients with hilar cholangiocarcinoma were analyzed, including 31 treated with stent plus stereotactic conformal radiotherapy (combined group) and 23 with metallic stent alone (control group). Results: The mean survival time of combined group was 11.1 ± 4.6 months, compared with 5.1 ± 2.8 months of the control group, giving a significant difference between the two groups (P<0.01). Conclusion: The combination of metallic stent and stereotactic conformal radiotherapy is more effective than metallic stent alone for unresectable hilar cholangiocarcinoma. (authors)

  2. Application of a novel retrievable self-expanding stent in intracranial aneurysm treatment

    International Nuclear Information System (INIS)

    Yang Zhigang; Liu Jianmin; Xu Yi; Huang Qinghai; Hong Bo; Zhao Wenyuan; Zhao Rui

    2008-01-01

    Objective: To assess the value of a novel retrievable self-expanding stent system (LEO) in intracranial aneurysm treatment. Methods: 43 patients with 44 intracranial aneurysms treated with LEO stent were retrospectively analized, including 16 aneurysms with single-stent deployment, 25 with stent-assisted technique, 2 with double-stent deployment and one with double-stent assisted coils. Follow up was carried out through imaging and clinical course. Results: The stent was easy for repositioning and all the stents were delivered successfully, except 1 stent with unsatisfactory position, 1 with acute in-stent thrombosis. During follow up, 1 case showed chronic in-stent thrombus and one with intimal hyperplasia. 22 aneurysms got compact coiled during procedure. Among 29 follow up cases, 72.4% aneurysms were cured or improved, 13.8% were stable and three dissection aneurysms enlarged within short period and two patients died. Conclusion: The new retrievable self-expanding stent (LEO), with the advantages of controlled delivery, easy deployment and choice for various types is a valuable system for vascular reconstruction of intracranial aneurysm with thrombosis. (authors)

  3. Percutaneous transhepatic self-expanding metal stents for palliation ...

    African Journals Online (AJOL)

    Stent occlusion occurred in 4 patients (8%) within a week as result of stent migration (n=3) or presumed biliary sludge (n=1); 2 (4%) stents occluded between 7 days and 1 month. Four patients (8%) died during hospital admission due to pre-existing biliary sepsis (n=3) and pneumonia (n=1). Nine patients developed ...

  4. Management of colon stents based on Bernoulli's principle.

    Science.gov (United States)

    Uno, Yoshiharu

    2017-03-01

    The colonic self-expanding metal stent (SEMS) has been widely used for "bridge to surgery" and palliative therapy. However, if the spread of SEMS is insufficient, not only can a decompression effect not be obtained but also perforation and obstructive colitis can occur. The mechanism of occurrence of obstructive colitis and perforation was investigated by flow dynamics. Bernoulli's principle was applied, assuming that the cause of inflammation and perforation represented the pressure difference in the proximal lumen and stent. The variables considered were proximal lumen diameter, stent lumen diameter, flow rate into the proximal lumen, and fluid density. To model the right colon, the proximal lumen diameter was set at 50 mm. To model the left-side colon, the proximal lumen diameter was set at 30 mm. For both the right colon model and the left-side colon model, the difference in pressure between the proximal lumen and the stent was less than 20 mmHg, when the diameter of the stent lumen was 14 mm or more. Both the right colon model and the left-side colon model were 30 mmHg or more at 200 mL s -1 when the stent lumen was 10 mm or less. Even with an inflow rate of 90-110 mL s -1 , the pressure was 140 mmHg when the stent lumen diameter was 5 mm. In theory, in order to maintain the effectiveness of SEMS, it is necessary to keep the diameter of the stent lumen at 14 mm or more.

  5. Evaluation of anti-migration properties of biliary covered self-expandable metal stents.

    Science.gov (United States)

    Minaga, Kosuke; Kitano, Masayuki; Imai, Hajime; Harwani, Yogesh; Yamao, Kentaro; Kamata, Ken; Miyata, Takeshi; Omoto, Shunsuke; Kadosaka, Kumpei; Sakurai, Toshiharu; Nishida, Naoshi; Kudo, Masatoshi

    2016-08-14

    To assess anti-migration potential of six biliary covered self-expandable metal stents (C-SEMSs) by using a newly designed phantom model. In the phantom model, the stent was placed in differently sized holes in a silicone wall and retracted with a retraction robot. Resistance force to migration (RFM) was measured by a force gauge on the stent end. Radial force (RF) was measured with a RF measurement machine. Measured flare structure variables were the outer diameter, height, and taper angle of the flare (ODF, HF, and TAF, respectively). Correlations between RFM and RF or flare variables were analyzed using a linear correlated model. Out of the six stents, five stents were braided, the other was laser-cut. The RF and RFM of each stent were expressed as the average of five replicate measurements. For all six stents, RFM and RF decreased as the hole diameter increased. For all six stents, RFM and RF correlated strongly when the stent had not fully expanded. This correlation was not observed in the five braided stents excluding the laser cut stent. For all six stents, there was a strong correlation between RFM and TAF when the stent fully expanded. For the five braided stents, RFM after full stent expansion correlated strongly with all three stent flare structure variables (ODF, HF, and TAF). The laser-cut C-SEMS had higher RFMs than the braided C-SEMSs regardless of expansion state. RF was an important anti-migration property when the C-SEMS did not fully expand. Once fully expanded, stent flare structure variables plays an important role in anti-migration.

  6. The interventional treatment with two stents in malignant hilar obstruction

    International Nuclear Information System (INIS)

    Gao Kun; Dai Dingke; Zhao Renyou; Qian Xiaojun

    2006-01-01

    Objective: To evaluate the methodology of interventional treatment with two stents in malignant hilar obstructions. Methods: Retrospectively analyzing the two stents, interventional management of unresectable malignant hilar obstruction in 22 patients included unilateral and bilateral puncture routes for placing 'T' shape stent set and 'Y' shape stent set, respectively; together with recording the related complications. Results: The overall technical success rate was 100%, without severe complication. The total serum bilirubin reduced from (337.9 + 81.7) μmol/L before procedure to (129.1 + 51.1) μmol/L after the stent placement. Stent obstruction was found in 8 cases at 6 months; 5 cases by the time of 6-12 months and only 2 cases after 1 year. Conclusion: The method of two stents interventional treatment is a safe and useful management for malignant hilar obstructions. (authors)

  7. Comparison of the Absorbable Polymer Sirolimus-Eluting Stent (MiStent) to the Durable Polymer Everolimus-Eluting Stent (Xience) (from the DESSOLVE I/II and ISAR-TEST-4 Studies).

    Science.gov (United States)

    Lansky, Alexandra J; Kastrati, Adnan; Edelman, Elazer R; Parise, Helen; Ng, Vivian G; Ormiston, John; Wijns, William; Byrne, Robert A

    2016-02-15

    We compared the outcomes of a novel, thin-strut, cobalt-chromium, absorbable, polymer sirolimus-eluting stent (APSES; MiStent) to the durable polymer cobalt-chromium everolimus-eluting stent (EES; Xience). A propensity-matched analysis was performed comparing data from the DES With Sirolimus and a Bioabsorbable Polymer for the Treatment of Patients With De Novo Lesions in the Native Coronary Arteries (DESSOLVE) I and II studies, evaluating the APSES to the EES arm of the Intracoronary Stenting and Angiographic Results: Test Efficacy of 3 Limus-Eluting Stents-4 study. Target lesion failure (TLF) and its components were evaluated at 12 months and annually to 3 years; 805 patients (APSES = 153; EES = 652) were included with propensity matching in 204 patients (APSES = 102; EES = 102). APSES compared with EES had lower TLF at 1 year (3.0% vs 8.0%, p = 0.12) driven by a difference in target lesion revascularization (TLR; 1% vs 6%, p = 0.05), with no difference in target vessel myocardial infarction (p = 0.56) or stent thrombosis (p = 0.31). At 3 years, TLF (5.0% vs 12.5%, p = 0.07) and TLR (2.0% vs 8.4%, p = 0.04) remained lower with APSES. By landmark analysis, there was no significant difference in TLF between 1 and 3 years (p = 0.36). In conclusion, in a propensity-matched analysis, the APSES demonstrated reduced clinically indicated TLR rates at 1 and 3 years compared with the durable polymer EES, with minimal accrual of events between 1 and 3 years. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. Distinctive effects of CD34- and CD133-specific antibody-coated stents on re-endothelialization and in-stent restenosis at the early phase of vascular injury

    Science.gov (United States)

    Wu, Xue; Yin, Tieying; Tian, Jie; Tang, Chaojun; Huang, Junli; Zhao, Yinping; Zhang, Xiaojuan; Deng, Xiaoyan; Fan, Yubo; Yu, Donghong; Wang, Guixue

    2015-01-01

    It is not clear what effects of CD34- and CD133-specific antibody-coated stents have on re-endothelialization and in-stent restenosis (ISR) at the early phase of vascular injury. This study aims at determining the capabilities of different coatings on stents (e.g. gelatin, anti-CD133 and anti-CD34 antibodies) to promote adhesion and proliferation of endothelial progenitor cells (EPCs). The in vitro study revealed that the adhesion force enabled the EPCs coated on glass slides to withstand flow-induced shear stress, so that allowing for the growth of the cells on the slides for 48 h. The in vivo experiment using a rabbit model in which the coated stents with different substrates were implanted showed that anti-CD34 and anti-CD133 antibody-coated stents markedly reduced the intima area and restenosis than bare mental stents (BMS) and gelatin-coated stents. Compared with the anti-CD34 antibody-coated stents, the time of cells adhesion was longer and earlier present in the anti-CD133 antibody-coated stents and anti-CD133 antibody-coated stents have superiority in re-endothelialization and inhibition of ISR. In conclusion, this study demonstrated that anti-CD133 antibody as a stent coating for capturing EPCs is better than anti-CD34 antibody in promoting endothelialization and reducing ISR. PMID:26813006

  9. Metallic stents for management of malignant biliary obstruction

    International Nuclear Information System (INIS)

    Lee, Byung Hee; Do, Young Soo; Byun, Hong Sik; Kim, Kie Hwan; Chin, Soo Yil

    1992-01-01

    In patients with inoperable malignant biliary obstruction, percutaneous transhepatic biliary drainage (PTBD) has been the method of choice for palliative treatment. All patients except three had undergone PTBD, and the stents were placed 5-7 days after the initial drainage procedure. Three patients underwent stent placement on the same day of PTBD. External drainage catheter is converted to various types of tube endoprostheses with associated physiologic and psychologic benefits. Tube stents, however, have some problems such as migration, occlusion, and traumatic implantation procedure. We report our experiences and clinical results of percutaneous placement of metallic stents in 40 patients with malignant biliary obstruction

  10. Treatment of ureterovaginal fistula using a Memokath stent

    DEFF Research Database (Denmark)

    Mohammad, Wael; Fode, Mikkel Mejlgaard; Azawi, Nessn Htum

    2014-01-01

    results in non-radiated patients. Meanwhile, conservative treatment using ureteral stents in selected patients has resulted in reported success rates of 71%. We present the case of a 24-year-old woman with UVF due to surgery and radiotherapy for cervix cancer. The patient has been successfully treated...... with the insertion of a Memokath 051 stent (PNN Medical A/S, Denmark), which is a thermoexpandable, nickel-titanium alloy stent. The patient has been totally continent during a follow-up period of 3 years. The Memokath stent has been changed twice within this period due to dysfunction....

  11. Metallic stents for management of malignant biliary obstruction

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Byung Hee; Do, Young Soo; Byun, Hong Sik; Kim, Kie Hwan; Chin, Soo Yil [Korea Cancer Center Hospital, Seoul (Korea, Republic of)

    1992-11-15

    In patients with inoperable malignant biliary obstruction, percutaneous transhepatic biliary drainage (PTBD) has been the method of choice for palliative treatment. All patients except three had undergone PTBD, and the stents were placed 5-7 days after the initial drainage procedure. Three patients underwent stent placement on the same day of PTBD. External drainage catheter is converted to various types of tube endoprostheses with associated physiologic and psychologic benefits. Tube stents, however, have some problems such as migration, occlusion, and traumatic implantation procedure. We report our experiences and clinical results of percutaneous placement of metallic stents in 40 patients with malignant biliary obstruction.

  12. Long-Term Type 1 Diabetes Enhances In-Stent Restenosis after Aortic Stenting in Diabetes-Prone BB Rats

    NARCIS (Netherlands)

    Onuta, Geanina; Groenewegen, Hendrik C.; Klatter, Flip A.; Boer, Mark Walther; Goris, Maaike; van Goor, Harry; Roks, Anton J. M.; Rozing, Jan; de Smet, Bart J. G. L.; Hillebrands, Jan-Luuk

    2011-01-01

    Type 1 diabetic patients have increased risk of developing in-stent restenosis following endovascular stenting. Underlying pathogenetic mechanisms are not fully understood partly due to the lack of a relevant animal model to study the effect(s) of long-term autoimmune diabetes on development of

  13. Long-term type 1 diabetes enhances in-stent restenosis after aortic stenting in diabetes-prone BB rats

    NARCIS (Netherlands)

    J.-L. Hillebrands (Jan-Luuk); G. Onuta (Geanina); H.C. Groenewegen (Hendrik); F.A. Klatter (Flip); M. Walther Boer (Mark); M. Goris (Maaike); H. van Goor (Harry); A.J.M. Roks (Anton); J. Rozing (Jan); B.J.G.L. de Smet (Bart)

    2011-01-01

    textabstractType 1 diabetic patients have increased risk of developing in-stent restenosis following endovascular stenting. Underlying pathogenetic mechanisms are not fully understood partly due to the lack of a relevant animal model to study the effect(s) of long-term autoimmune diabetes on

  14. Antegrade Ureteral Stenting is a Good Alternative for the Retrograde Approach.

    Science.gov (United States)

    van der Meer, Rutger W; Weltings, Saskia; van Erkel, Arian R; Roshani, Hossain; Elzevier, Henk W; van Dijk, Lukas C; van Overhagen, Hans

    2017-07-01

    Double J (JJ) stents for treating obstructive ureteral pathology are generally inserted through a retrograde route with cystoscopic guidance. Antegrade percutaneous insertion using fluoroscopy can be performed alternatively but is less known. Indications, success rate and complications of antegrade ureteral stenting were evaluated. Data of consecutive patients in which antegrade ureteral stenting was performed were retrospectively analysed using the radiology information system and patient records. Patient characteristics, details of the antegrade JJ stent insertion procedure and registered complications were collected. Furthermore, it was investigated if prior to the antegrade procedure a retrograde attempt for JJ stent insertion was performed. Total 130 attempts for antegrade JJ stent insertion were performed in 100 patients. A percutaneous nephrostomy catheter had already been placed in the majority of kidneys (n = 109) for initial treatment of hydronephrosis. Most prevelant indication for a JJ stent was obstructive ureteral pathology due to malignancy (n = 63). A JJ stent was successfully inserted in 125 of 130 procedures. In 21 cases, previous retrograde ureteral stenting had failed but, subsequent antegrade ureteral stenting was successful. There were 8 procedure related complications; 6 infections, 1 false tract and 1 malposition. Antegrade percutaneous insertion of a JJ stent is a good alternative for retrograde insertion.

  15. Covered stent to exclude intravascular thrombus.

    Science.gov (United States)

    Liistro, Francesco; Stankovic, Goran; Di Mario, Carlo; Montorfano, Matteo; Briguori, Carlo; Colombo, Antonio

    2002-04-01

    To describe the utility of stent-graft implantation to avoid distal embolization from a large thrombus-containing lesion. A 67-year-old man was evaluated for recent onset of disabling left leg claudication. Angiography disclosed a mobile lobular mass occluding the left common iliac artery; irregular staining suggested an atherothrombotic lesion. Through a percutaneous ipsilateral access and an 8-F sheath, a balloon-expandable Jostent peripheral stent-graft was positioned with the distal edge immediately proximal to the internal iliac artery ostium. A prominent "waist" at the center of the balloon confirmed entrapment of the thrombotic mass. Completion angiography showed an optimal result with no residual stenosis or evidence of distal embolization. At 6-month follow-up, the patient was asymptomatic with angiographically documented luminal patency and no evidence of in-stent stenosis. Stent-graft implantation appears a viable treatment alternative for thrombus-containing lesions, particularly when the thrombotic material is localized or is in a large vessel.

  16. The underdilation of nitinol stents at TIPS implantation: Solution or illusion?

    Energy Technology Data Exchange (ETDEWEB)

    Mollaiyan, Ashkan [University Hospital, Department of Radiology, Hugstetterstrasse 55, 79106 Freiburg (Germany); Bettinger, Dominik [University Hospital, Department of Gastroenterology, Hugstetterstrasse 55, 79106 Freiburg (Germany); Berta-Ottenstein-Programme, Faculty of Medicine, University of Freiburg (Germany); Rössle, Martin, E-mail: Martin-Roessle@t-online.de [University Hospital, Department of Gastroenterology, Hugstetterstrasse 55, 79106 Freiburg (Germany); Praxiszentrum für Gastroenterologie, Bertoldstrasse 48, 79098 Freiburg (Germany)

    2017-04-15

    Purpose: This study investigates the behaviour of self-expanding nitinol stents at the time of TIPS-implantation and thereafter. Methods: Hundred consecutive patients with cirrhosis receiving a TIPS revision were included. The smallest stent diameter was measured radiologically immediately after implantation and before shunt revision. Accuracy of the measurement was assessed by comparing the nominal stent diameter with the largest stent diameter measured at the time of revision. Results: Pearson correlation between largest measured and nominal diameters was excellent (r = 0.952, p < 0.001) showing that measurements are accurate. At TIPS implantation all stents were markedly underdilated reaching only 76–92% of their nominal diameter. Smallest measured diameters were similar (8 mm) irrespective of the nominal diameter (8, 9, 10 mm) of the stent. In addition, smallest diameters of 10 mm stents were similar irrespective whether 8, 9 or 10 mm balloons were used. During a mean follow-up of 12.7 ± 17.8 months (median 3 months, range 1–81) stents expanded by 0.5–1.6 mm dependent on the nominal stent size (8, 9, 10 mm) and the grade of primary underdilation. No significant difference was found between Viatorr and bare stents. Conclusions: At TIPS-implantation, the compliance of the surrounding tissue predominantly determines the stent diameter. The nominal size of the stent or the dilatation balloon has little influence. Accurate adjustment of a desired pressure gradient is, therefore, not possible. During follow-up, stents expand towards their nominal diameter questioning the usefulness of underdilation.

  17. The underdilation of nitinol stents at TIPS implantation: Solution or illusion?

    International Nuclear Information System (INIS)

    Mollaiyan, Ashkan; Bettinger, Dominik; Rössle, Martin

    2017-01-01

    Purpose: This study investigates the behaviour of self-expanding nitinol stents at the time of TIPS-implantation and thereafter. Methods: Hundred consecutive patients with cirrhosis receiving a TIPS revision were included. The smallest stent diameter was measured radiologically immediately after implantation and before shunt revision. Accuracy of the measurement was assessed by comparing the nominal stent diameter with the largest stent diameter measured at the time of revision. Results: Pearson correlation between largest measured and nominal diameters was excellent (r = 0.952, p < 0.001) showing that measurements are accurate. At TIPS implantation all stents were markedly underdilated reaching only 76–92% of their nominal diameter. Smallest measured diameters were similar (8 mm) irrespective of the nominal diameter (8, 9, 10 mm) of the stent. In addition, smallest diameters of 10 mm stents were similar irrespective whether 8, 9 or 10 mm balloons were used. During a mean follow-up of 12.7 ± 17.8 months (median 3 months, range 1–81) stents expanded by 0.5–1.6 mm dependent on the nominal stent size (8, 9, 10 mm) and the grade of primary underdilation. No significant difference was found between Viatorr and bare stents. Conclusions: At TIPS-implantation, the compliance of the surrounding tissue predominantly determines the stent diameter. The nominal size of the stent or the dilatation balloon has little influence. Accurate adjustment of a desired pressure gradient is, therefore, not possible. During follow-up, stents expand towards their nominal diameter questioning the usefulness of underdilation.

  18. 3-Year Clinical Follow-Up of the RIBS IV Clinical Trial: A Prospective Randomized Study of Drug-Eluting Balloons Versus Everolimus-Eluting Stents in Patients With In-Stent Restenosis in Coronary Arteries Previously Treated With Drug-Eluting Stents.

    Science.gov (United States)

    Alfonso, Fernando; Pérez-Vizcayno, María José; Cuesta, Javier; García Del Blanco, Bruno; García-Touchard, Arturo; López-Mínguez, José Ramón; Masotti, Mónica; Zueco, Javier; Cequier, Angel; Velázquez, Maite; Moreno, Raúl; Mainar, Vicente; Domínguez, Antonio; Moris, Cesar; Molina, Eduardo; Rivero, Fernando; Jiménez-Quevedo, Pilar; Gonzalo, Nieves; Fernández-Pérez, Cristina

    2018-05-28

    This study sought to compare the long-term safety and efficacy of drug-eluting balloons (DEB) and everolimus-eluting stents (EES) in patients with in-stent restenosis (ISR) of drug-eluting stents (DES). Treatment of patients with DES-ISR remains a challenge. The RIBS IV (Restenosis Intra-Stent of Drug-Eluting Stents: Drug-Eluting Balloons vs Everolimus-Eluting Stents) trial is a prospective multicenter randomized clinical trial comparing DEB and EES in patients with DES-ISR. The pre-specified comparison of the 3-year clinical outcomes obtained with these interventions is the main objective of the present study. A total of 309 patients with DES-ISR were randomized to DEB (n = 154) or EES (n = 155). At angiographic follow-up, the in-segment minimal lumen diameter was larger in the EES arm (2.03 ± 0.7 mm vs. 1.80 ± 0.6 mm; p 1 year) target lesion revascularization (2.6% vs. 4%) and target vessel revascularization (4% vs. 6.6%) was similar in the 2 arms. Rates of cardiac death (3.9% vs. 3.2%), myocardial infarction (2.6% vs. 4.5%), and stent thrombosis (1.3% vs. 2.6%) at 3 years were also similar in both arms. The 3-year clinical follow-up of this randomized clinical trial demonstrates that in patients with DES-ISR, EES reduce the need for repeat interventions compared with DEB. (Restenosis Intra-Stent of Drug-Eluting Stents: Drug-Eluting Balloons vs Everolimus-Eluting Stents [RIBS IV]; NCT01239940). Published by Elsevier Inc.

  19. Timing of silicone stent removal in patients with post-tuberculosis bronchial stenosis.

    Science.gov (United States)

    Eom, Jung Seop; Kim, Hojoong; Park, Hye Yun; Jeon, Kyeongman; Um, Sang-Won; Koh, Won-Jung; Suh, Gee Young; Chung, Man Pyo; Kwon, O Jung

    2013-10-01

    In patients with post-tuberculosis bronchial stenosis (PTBS), the severity of bronchial stenosis affects the restenosis rate after the silicone stent is removed. In PTBS patients with incomplete bronchial obstruction, who had a favorable prognosis, the timing of stent removal to ensure airway patency is not clear. We evaluated the time for silicone stent removal in patients with incomplete PTBS. A retrospective study examined PTBS patients who underwent stenting and removal of a silicone stent. Incomplete bronchial stenosis was defined as PTBS other than total bronchial obstruction, which had a luminal opening at the stenotic segment on bronchoscopic intervention. The duration of stenting was defined as the interval from stent insertion to removal. The study included 44 PTBS patients and the patients were grouped at intervals of 6 months according to the duration of stenting. Patients stented for more than 12 months had a significantly lower restenosis rate than those stented for less than 12 months (4% vs. 35%, P = 0.009). Multiple logistic regression revealed an association between stenting for more than 12 months and a low restenosis rate (odds ratio 12.095; 95% confidence interval 1.097-133.377). Moreover, no restenosis was observed in PTBS patients when the stent was placed more than 14 months previously. In patients with incomplete PTBS, stent placement for longer than 12 months reduced restenosis after stent removal.

  20. A scanning electron microscopic study of biliary stent materials

    NARCIS (Netherlands)

    van Berkel, A. M.; van Marle, J.; van Veen, H.; Groen, A. K.; Huibregtse, K.

    2000-01-01

    Clogging of biliary stents remains an important problem. In vitro studies have shown less sludge formation in Teflon stents. Recently, clinical studies with Teflon stents have produced contradictory results. The aim of this study was to investigate whether the surface properties of the

  1. Silicone covered vs. Non- covered endotracheal self expandable metallic stent: An experimental study

    Energy Technology Data Exchange (ETDEWEB)

    Do, Young Soo; Lee, Byung Hee; Kim, Soo Ah; Kim, Kie Hwan; Chin, Soo Yil; Cho, Kyung Ja; Cho, Dae Soon [Korea Cancer Center Hospital, Seoul (Korea, Republic of)

    1994-10-15

    To evaluate pathologic changes of the trachea and the lung after insertion of silicone covered and non covered Gianturco stent in the trachea of dog. Silicone covered(covered) and non covered(bare) Gianturco stent, six in each, were inserted into the tracheal lumen of six consecutive dogs. After 1-10 weeks observation, the dogs were sacrificed and their tracheas and lungs were examined grossly and histopathologically. Serial chest radiographs were performed to evaluate pneumonia and stent migration every 3-5 days. Pneumonia was observed in one of bare stent group and five of covered stent group. Stent migration was noted in three of covered stent group. In bare stent group, the epithelium of the trachea was markedly thickened by hyperplasia and stent was covered by granulation tissue from 6 weeks after stent insertion. Inflammation was focal at contact site between the stent and the trachea. In covered stent group, the epithelium was denuded at multiple areas and there were multifocal squamous metaplasia of the mucosa. Inflammatory reaction of the trachea was diffuse. Inflammatory reaction was more severe and stent migration was more frequent in covered stent group. The use of covered stent in the trachea should be studied further.

  2. Safety and efficacy of limus-eluting stents and balloon angioplasty for sirolimus-eluting in-stent restenosis

    Energy Technology Data Exchange (ETDEWEB)

    Ota, Hideaki [Division of Interventional Cardiology, MedStar Washington Hospital Center, Washington, DC 20010 (United States); Mahmoudi, Michael [University of Surrey, Guildford Road, Surrey, GU2-7XH (United Kingdom); Kitabata, Hironori; Torguson, Rebecca; Chen, Fang; Satler, Lowell F.; Suddath, William O.; Pichard, Augusto D. [Division of Interventional Cardiology, MedStar Washington Hospital Center, Washington, DC 20010 (United States); Waksman, Ron, E-mail: ron.waksman@medstar.net [Division of Interventional Cardiology, MedStar Washington Hospital Center, Washington, DC 20010 (United States)

    2015-03-15

    Objectives: The aim of this study was to compare the safety and efficacy of everolimus-eluting stent (EES), sirolimus-eluting stent (SES), and plain old balloon angioplasty (POBA) for the treatment of SES in-stent restenosis (S-ISR). Background: The optimal treatment for drug-eluting in-stent restenosis remains controversial. Methods: The study cohort comprised 310 consecutive patients (444 lesions) who presented with S-ISR to our institution and underwent treatment with EES (43 patients), SES (102), or POBA (165). The analyzed clinical parameters were the 1-year rates of death, Q-wave myocardial infarction (MI), target lesion revascularization (TLR), target vessel revascularization (TVR), definite stent thrombosis (ST) and major adverse cardiac event (MACE) defined as the composite of death, MI, or TLR at 1-year. Results: The three groups were well matched for the conventional risk factors for coronary artery disease except for smoking. The 1-year analyzed clinical parameters were similar in the three groups: MACE (EES = 14%, SES = 18%, POBA = 20%; p = 0.65), death (EES = 2.3%, SES = 6.2%, POBA = 6.1%; p = 0.61), MI (EES = 4.8%, SES = 2.1%, POBA = 2.5%; p = 0.69), TLR (EES = 11.9%, SES = 12.1%, POBA = 24%; p = 0.78), and TVR (EES = 11.9%, SES = 24.8%, POBA = 22.2%; p = 0.23). There were no cases of definite ST. MACE-free rate was significantly lower in patients with recurrent in-stent restenosis (log-rank p = 0.006). Presentation with acute MI, number of treated lesions and a previous history of MI were found to be independent predictors of MACE. Conclusions: In patients presenting with S-ISR, treatment with implantation of an EES, SES, or POBA is associated with similar clinical outcomes. Patients presenting with recurrent ISR may have a poorer clinical outcome.

  3. Trans-Stent B-Mode Ultrasound and Passive Cavitation Imaging.

    Science.gov (United States)

    Haworth, Kevin J; Raymond, Jason L; Radhakrishnan, Kirthi; Moody, Melanie R; Huang, Shao-Ling; Peng, Tao; Shekhar, Himanshu; Klegerman, Melvin E; Kim, Hyunggun; McPherson, David D; Holland, Christy K

    2016-02-01

    Angioplasty and stenting of a stenosed artery enable acute restoration of blood flow. However, restenosis or a lack of re-endothelization can subsequently occur depending on the stent type. Cavitation-mediated drug delivery is a potential therapy for these conditions, but requires that particular types of cavitation be induced by ultrasound insonation. Because of the heterogeneity of tissue and stochastic nature of cavitation, feedback mechanisms are needed to determine whether the sustained bubble activity is induced. The objective of this study was to determine the feasibility of passive cavitation imaging through a metal stent in a flow phantom and an animal model. In this study, an endovascular stent was deployed in a flow phantom and in porcine femoral arteries. Fluorophore-labeled echogenic liposomes, a theragnostic ultrasound contrast agent, were injected proximal to the stent. Cavitation images were obtained by passively recording and beamforming the acoustic emissions from echogenic liposomes insonified with a low-frequency (500 kHz) transducer. In vitro experiments revealed that the signal-to-noise ratio for detecting stable cavitation activity through the stent was greater than 8 dB. The stent did not significantly reduce the signal-to-noise ratio. Trans-stent cavitation activity was also detected in vivo via passive cavitation imaging when echogenic liposomes were insonified by the 500-kHz transducer. When stable cavitation was detected, delivery of the fluorophore into the arterial wall was observed. Increased echogenicity within the stent was also observed when echogenic liposomes were administered. Thus, both B-mode ultrasound imaging and cavitation imaging are feasible in the presence of an endovascular stent in vivo. Demonstration of this capability supports future studies to monitor restenosis with contrast-enhanced ultrasound and pursue image-guided ultrasound-mediated drug delivery to inhibit restenosis. Copyright © 2016 World Federation for

  4. Treatment of Intra- and Extracranial Arterial Dissections Using Stents and Embolization

    International Nuclear Information System (INIS)

    Joo, Jin Yang; Ahn, Jung Yong; Chung, Young Sun; Han, In Bo; Chung, Sang Sup; Yoon, Pyeong Ho; Kim, Sang Heum; Choi, Eun Wan

    2005-01-01

    Purpose. To evaluate the safety and efficacy of stent placement for extracranial and intracranial arterial dissections. Methods. Eighteen patients underwent endovascular treatment of carotid and vertebral dissections using intraluminal stent placement. Five patients with arterial dissection were treated, 2 using one insertion of a single stent and 3 using placement of two stents. Patients with a dissecting aneurysm were treated as follows: 7 patients with insertion of one stent, 4 with placement of two stents, and 2 by stent-assisted Guglielmi detachable coil embolization. In the 18 patients in whom stenting was attempted, the overall success in reaching the target lesion was 94.4%. Of the 17 patients treated with stents, stent release and positioning were considered optimal in 16 (94%) and suboptimal in one (6%). In patients who underwent a successful procedure, all parent arteries were preserved. There were no instances of postprocedural ischemic attacks, new neurologic deficits, or new minor or major strokes prior to patient discharge. In follow up, all patients were assessed, using the modified Rankin scale, as functionally improved or of stable clinical status. The reduction in dissection-induced stenosis or pseudoaneurysm, the patency rate obtained at follow-up, and the lack of strokes (ischemic or hemorrhagic) suggest that stent placement offers a viable alternative to complex surgical bypass or reconstructive procedures. The long-term efficacy and durability of stent placement for arterial dissection remain to be determined in a larger series

  5. Feasibility of Angioplasty and Stenting for Abdominal Aortic Lesions Adjacent to Previously Stented Visceral Artery Lesions in Patients with Takayasu Arteritis

    International Nuclear Information System (INIS)

    Joseph, George; George, Paul V.; Pati, Purendra Kumar; Chandy, Sunil Thomas

    2007-01-01

    Two young female patients with Takayasu arteritis presented with symptomatic long-segment abdominal aortic stenosis in the vicinity of previously deployed celiac and renal artery stents that projected markedly into the narrowed aortic lumen. Crushing or distortion of the visceral artery stents during aortic angioplasty was avoided by performing simultaneous or alternating balloon dilatations in the aorta and in the visceral artery stents. Consequently, the visceral artery stents remained patent and shortened longitudinally, allowing unhindered deployment of Wallstents in the adjacent aorta and abolition of a pressure gradient across the aortic lesions. Access to side branches covered by the Wallstent was obtained without difficulty, enabling the performance of balloon dilatation in multiple side branches and ostial stent deployment in a renal artery. These techniques could increase the scope of endovascular therapy in the treatment of patients with Takayasu arteritis

  6. Biodegradable airway stents in infants - Potential life-threatening pitfalls.

    Science.gov (United States)

    Sztanó, B; Kiss, G; Márai, K; Rácz, G; Szegesdi, I; Rácz, K; Katona, G; Rovó, L

    2016-12-01

    The solution of severe tracheobronchial obstructions in early childhood means a great challenge. Biodegradable stents were intended to be a minimally invasive temporary solution which may decrease the number of interventions and limit the possible complications of stenting procedures. However, our first experiences have brought out a new, - especially in childhood - potentially life-threatening complication of this concept. Five SX-ELLA biodegradable polydioxanone stents was applied in three patients because of severe tracheobronchial obstruction: congenital tracheomalacia (7 day-old), acquired tracheomalacia (10 month-old), and congenital trachea-bronchomalacia (10 month-old). The breathing of all children improved right after the procedure. We observed degradation of the stent from the 5th postoperative week which resulted in large intraluminar fragments causing significant airway obstruction: one patient died of severe pneumonia, the other baby required urgent bronchoscopy to remove the obstructing 'foreign body' from the trachea. In the third case repeated stent placements successfully maintained the tracheal lumen. Polydioxanone stents may offer an alternative to metallic or silastic stents for collapse or external compression of the trachea in children; however, large decaying fragments mean a potential risk especially in the small size pediatric airway. The fragmentation of the stent, which generally starts in the 4-6 postoperative weeks, may create large sharp pieces. These may be anchored to the mucosa and covered by crust leading to obstruction. As repeated interventions are required, we do not consider the application of biodegradable stents unambiguously advantageous. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  7. A Case of Late Femoral Pseudoaneurysm Caused by Stent Disconnection

    International Nuclear Information System (INIS)

    Rivolta, Nicola; Fontana, Federico; Piffaretti, Gabriele; Tozzi, Matteo; Carrafiello, Gianpaolo

    2010-01-01

    We present the case of a late superficial femoral artery stent disconnection causing an asymptomatic pseudoaneurysm successfully treated with a stent-graft. A 67-year-old female was referred to our department for evaluation of claudication of the left lower limb and was diagnosed to have a total occlusion of the superficial femoral artery. Three nitinol stents were used to revascularize this artery. At 48 months, duplex-ultrasonography control revealed the presence of a 45-mm saccular femoral dilatation; X-rays and CT angiography showed fractures of the proximal stents and the presence of a pseudoaneurysm at the site of the distal stents disconnection. The pseudoaneurysm was excluded using two stent-grafts. We conclude that patients and surgeons should be aware of structural complications with all stents. Rigorous follow-up controls should be mandatory. Endovascular repair proved to be feasible and durable to manage a previous endovascular procedure.

  8. Transanal stent in anterior resection does not prevent anastomotic leakage

    DEFF Research Database (Denmark)

    Bülow, Steffen; Bulut, O; Christensen, Ib Jarle

    2006-01-01

    OBJECTIVE: A defunctioning transanal stent may theoretically reduce the leakage rate after anterior rectal resection. We present a randomized open study with the aim of comparing the leakage rate after anterior resection with a loop ileostomy, a transanal stent, both or neither. PATIENTS...... completion of the operation the patients were randomized in two groups with and without a transanal stent. RESULTS: A clinically significant leakage was diagnosed in 25 patients (13%). No significant difference was found 17 of 98 patients with a stent and 8 of 96 without (P = 0.09), or in 9 of 44 ileostomy...... patients with a stent and in 3 of 45 without (P = 0.07). Several leaks over a short time led to an interim analysis after inclusion of 194 of 448 planned patients. The analysis showed no significant protective effect of the stent, and more leakages in the stent group, although not statistically significant...

  9. Transluminal endovascular stent-graft for the treatment of aortic aneurysms

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Do Yun; Chang, Byung Chul; Shim, Won Heum; Cho, Seung Yun; Chung, Nam Sik; Kwon, Hyuk Moon; Lee, Young Joon; Lee, Jong Tae [Yonsei University College of Medicine, Seoul (Korea, Republic of)

    1995-09-15

    The standard treatment for aortic aneurysms is surgical replacement with a prosthetic graft. Currently there is great interest in endoluminal intervention for treatment of aortic aneurysm. The purpose of this study was to evaluate the safety and effectiveness of endoluminally placed Stent-graft for the treatment of aortic aneurysms. Transluminal endovascular Stent-graft placements were attempted in 9 patients with infra-renal aortic aneurysms(n 6), thoracic aortic aneurysm(n = 1), and aortic dissection(n = 2). The endovascular Stent-grafts were custom-designed for each patient and were constructed of self-expandable modified Gianturco Stents covered with polytetrafluroethylene. The Stent-grafts were introduced through a 16-18 French sheath and expanded to 17-30 mm in diameter. The endovascular therapy was performed using a common femoral artery cutdown with local anesthesia. The endovascular Stent-graft deployment was achieved in 7 of 9 patients. Two cases failed deployment of the Stent-graft due to iliac artery stenosis and tortousity. There were complete thrombosis of the thoracic and infra-renal aortic aneurysm surround the Stent-graft in 3 patients, and persistent leak with partial thrombosis in 2. Two patients with aortic dissection were successfully treated by obliteration of entry tears. There were no major complication associated with Stent-graft placement. These preliminary results show that transluminal endovascular Stent-grafts offer great promise and good results. Further investigation is needed to establish its long-term safety and efficacy.

  10. Transluminal endovascular stent-graft for the treatment of aortic aneurysms

    International Nuclear Information System (INIS)

    Lee, Do Yun; Chang, Byung Chul; Shim, Won Heum; Cho, Seung Yun; Chung, Nam Sik; Kwon, Hyuk Moon; Lee, Young Joon; Lee, Jong Tae

    1995-01-01

    The standard treatment for aortic aneurysms is surgical replacement with a prosthetic graft. Currently there is great interest in endoluminal intervention for treatment of aortic aneurysm. The purpose of this study was to evaluate the safety and effectiveness of endoluminally placed Stent-graft for the treatment of aortic aneurysms. Transluminal endovascular Stent-graft placements were attempted in 9 patients with infra-renal aortic aneurysms(n 6), thoracic aortic aneurysm(n = 1), and aortic dissection(n = 2). The endovascular Stent-grafts were custom-designed for each patient and were constructed of self-expandable modified Gianturco Stents covered with polytetrafluroethylene. The Stent-grafts were introduced through a 16-18 French sheath and expanded to 17-30 mm in diameter. The endovascular therapy was performed using a common femoral artery cutdown with local anesthesia. The endovascular Stent-graft deployment was achieved in 7 of 9 patients. Two cases failed deployment of the Stent-graft due to iliac artery stenosis and tortousity. There were complete thrombosis of the thoracic and infra-renal aortic aneurysm surround the Stent-graft in 3 patients, and persistent leak with partial thrombosis in 2. Two patients with aortic dissection were successfully treated by obliteration of entry tears. There were no major complication associated with Stent-graft placement. These preliminary results show that transluminal endovascular Stent-grafts offer great promise and good results. Further investigation is needed to establish its long-term safety and efficacy

  11. Angioplasty and stent placement - carotid artery - discharge

    Science.gov (United States)

    ... medlineplus.gov/ency/patientinstructions/000235.htm Angioplasty and stent placement - carotid artery - discharge To use the sharing ... the hospital. You may have also had a stent (a tiny wire mesh tube) placed in the ...

  12. Angioplasty and stent placement - peripheral arteries - discharge

    Science.gov (United States)

    ... medlineplus.gov/ency/patientinstructions/000234.htm Angioplasty and stent placement - peripheral arteries - discharge To use the sharing ... peripheral artery). You may have also had a stent placed. To perform the procedure: Your doctor inserted ...

  13. Bilateral metal stents for hilar biliary obstruction using a 6Fr delivery system: outcomes following bilateral and side-by-side stent deployment.

    Science.gov (United States)

    Law, Ryan; Baron, Todd H

    2013-09-01

    Controversy exists on optimal endoscopic management for palliation of malignant hilar obstruction, with advocates for metal "side-by-side" (SBS) and "stent-in-stent" (SIS) techniques. We sought to evaluate the technical feasibility, efficacy, and outcomes of bilateral biliary self-expanding metal stents (SEMS) for treatment of malignant hilar obstruction using a stent with a 6Fr delivery system. This was a single-center, retrospective review of all patients who underwent bilateral placement of Zilver® biliary SEMS for malignant hilar obstruction from January 2010 to August 2012. Patients underwent endoscopic retrograde cholangiopancreatography with placement of stents using either the SIS or SBS stent techniques. Twenty-four patients (19 men, mean age 63 years) underwent bilateral stenting for malignant hilar obstruction during the study period. Seventeen and seven patients underwent the SBS and SIS technique, respectively. Cholangiocarcinoma (n=14) was the most common cause of hilar obstruction. Initial technical success was achieved in 24/24 (100%) of patients; however, 12 (50%) patients required re-intervention during the study period (median 98 days). Comparison of the SBS and SIS groups revealed no statistical difference with respect to need for re-intervention (P=0.31), successful re-intervention (P=0.60), or procedural length (P=0.89). Use of bilateral Zilver® SEMS in either the SBS or SIS configuration is safe, technically feasible, and effective for drainage of malignant hilar obstruction; however, duration of stent patency and procedure-free survival remain variable.

  14. In-stent stenosis after stent-assisted coiling: incidence, predictors and clinical outcomes of 435 cases.

    Science.gov (United States)

    Chalouhi, Nohra; Drueding, Ross; Starke, Robert M; Jabbour, Pascal; Dumont, Aaron S; Gonzalez, L Fernando; Rosenwasser, Robert; Tjoumakaris, Stavropoula

    2013-03-01

    Neuroform and Enterprise are widely used self-expanding stents designed to treat wide-necked intracranial aneurysms. To assess the incidence, clinical significance, predictors, and outcomes of in-stent stenosis (ISS). Angiographic studies and hospital records were retrospectively reviewed for 435 patients treated between 2005 and 2011 in our institution. A multivariable regression analysis was conducted to determine the predictors of ISS. The Neuroform stent was used in 264 patients (60.7%) and the Enterprise in 171 patients (39.3%). A total of 11 patients (2.5%) demonstrated some degree of ISS during the follow-up period at a mean time point of 4.2 months (range, 2-12 months). The stenosis was mild ( 75%) in 1 patient (0.2%). No patients were symptomatic or required further intervention. There was complete ISS resolution in 2 patients, partial resolution in 2 patients, and no change in 5 patients on follow-up angiography. Patients developing ISS were significantly younger than those without ISS (40.3 vs. 54.9 years; P stent (P = .6). In multivariable analysis, younger patient age (odds ratio = 0.92; P = .008), carotid ophthalmic aneurysm location (odds ratio = 7.7; P =0.01), and carotid terminus aneurysm location (odds ratio = 8.1; P = .009) were strong independent predictors of ISS. The type of stent was not a predictive factor. Neuroform and Enterprise ISS is an uncommon, often transient, and clinically benign complication. Younger patients and those harboring anterior circulation aneurysms located at ophthalmic and carotid terminus locations are more likely to develop ISS.

  15. Coronary Stents in Diabetic Patients: State of the Knowledge.

    Science.gov (United States)

    Codner, Pablo; Gurm, Hitinder Singh; Motivala, Apurva

    2017-04-01

    This review article aims to summarize the findings of the most relevant research that compared the use of paclitaxel vs. "limus" based drug eluting stent (DES) in diabetic patients and to define the current state of knowledge with new stent technologies in this patient population. Since drug eluting stents (DES) were introduced, it has been of great interest to establish whether paclitaxel or sirolimus eluting stents have the same safety and efficacy features for patients with coronary artery disease. The answer to this question is particularly relevant for diabetic patients. Several randomized trials, registry-based studies, and meta-analyses have assessed the performance of these different DES in diabetic patients. The most recently published data favors limus over paclitaxel DES in diabetic patients, but most of these studies compared first vs. second generation DES with the inherent caveats of comparing different platforms, alloys, and drug delivery vehicles. In this literature review, we found that there is robust evidence favoring the use of DES over bare metal stents in diabetic patients with coronary artery disease. We also found that the current state of knowledge is that the everolimus eluting stents have better safety and efficacy than paclitaxel eluting stents in diabetic patients and hence should be the preferred choice. New revascularization strategies including bio-absorbable scaffolds, polymer free stents, and bio-degradable polymers are being studied in diabetic patients with encouraging results.

  16. Early and mid-term results with the Growth Stent--a possible concept for transcatheter treatment of aortic coarctation from infancy to adulthood by stent implantation?

    Science.gov (United States)

    Ewert, Peter; Peters, Bjoern; Nagdyman, Nicole; Miera, Oliver; Kühne, Titus; Berger, Felix

    2008-01-01

    Evaluation of the Growth Stent-a stent consisting of two stent halves connected by reabsorbable sutures-for the treatment of aortic coarctation in infants. Surveillance study of 13 Growth Stents implanted in 12 patients aged 1-15 months (median 5 months). Body weight ranged from 3.4-12.8 kg (median 5.4 kg). Eight patients suffered from aortic (re-)coarctation, four of them from stenosis of the aortic anastomosis after a Norwood I procedure. The follow-up period was 24 months (11-51 months). Pressure gradients immediately after stent implantation decreased from 30 mm Hg (range 20-50 mm Hg) to 8 mm Hg (range 0-15 mm Hg). Five patients had one (3 pts) or two (2 pts) balloon dilations 3-28 months (median 12 months) after Growth Stent implantation. The median pressure gradient decreased from 25 mm Hg (range 15-30 mm Hg) to 15 mm Hg (range 5-25 mm Hg). Six patients received a large stent after 19-34 months. Median body weight was 11.8 kg (9.4-15 kg). The Growth Stent is suitable for the acute treatment of aortic coarctation in infants and can be overstented later on--if necessary--with a larger stent without causing restriction. Copyright 2008 Wiley-Liss, Inc.

  17. Stent-assisted angioplasty for intracranial atherosclerosis

    International Nuclear Information System (INIS)

    Nakahara, Toshinori; Sakamoto, Shigeyuki; Hamasaki, Osamu; Sakoda, Katsuaki

    2002-01-01

    We report on two patients with intracranial atherosclerosis of the carotid artery or vertebral artery treated with stent-assisted angioplasty. Both patients have severe intracranial atherosclerosis (>70%) with refractory symptoms despite optimal medical treatment. In both patients, a coronary balloon-expandable stent was successfully placed using a protective balloon technique without procedural complications. The patients were asymptomatic and neurologically intact at a mean clinical follow-up of 13 months. Follow-up angiograms did not show restenosis 3 or 4 months after procedure, respectively. Stent-assisted angioplasty for intracranial atherosclerosis in the elective patient has proven effective, with an acceptable low rate of morbidity and mortality. (orig.)

  18. An argument for the use of multiple segment stents in curved arteries.

    Science.gov (United States)

    Kasiri, Saeid; Kelly, Daniel J

    2011-08-01

    Stenting of curved arteries is generally perceived to be more challenging than straight vessels. Conceptually implanting multiple shorter stents rather than a single longer stent into such a curved artery represents a promising concept, but little is known about the impact of such an approach. The objective of this study is to evaluate the effectiveness of using a multiple segment stent rather than a single long stent to dilate a curved artery using the finite element method. A double segment stent (DSS) and a single segment stent (SSS) were modeled. The stents were compared when expanded into a model of a curved artery. The model predicts that the DSS provides higher flexibility, more conformity, and lower recoil in comparison to the SSS. The volume of arterial tissue experiencing high levels of stress due to stent implantation is also reduced for the DSS. It is suggested that a multiple segment stenting system is a potential solution to the problem of higher rates of in-stent restenosis in curved arteries and mechanically challenging environments.

  19. The application of DynaCT in performing the placement of intracranial stent

    International Nuclear Information System (INIS)

    Shen Hui; Wang Yongchun; Wang Minjie; Ding Hailing; Qin Yashan; Mao Yaqin; Li Songhua; Mao Yanjun; Hao Qiang

    2011-01-01

    Objective: To evaluate the clinical application of DynaCT technique in performing intracranial stent implantation. Methods: Thirty-nine patients who were planed to receive intracranial stent implantation were involved in this study. During the procedure DynaCT scanning was employed to monitor the real-time situation of stent implantation. Results: A total of 47 stents were implanted in intracranial vessels in the 39 patients. By using conventional angiography during operation the position of these stents was observed and was assured to be in the proper position. The adherence of these stents to the vascular wall was demonstrated with DynaCT multi-planar reconstruction images and the stent adherence in good condition was ensured. Conclusion: DynaCT applied during and after intracranial stent implantation is very helpful for displaying the contours of the stents as well as the vascular lumen and for providing a detail picture of the relationship between the stent and the surrounding anatomy. Therefore, DynaCT scanning is of great clinical significance for performing the intracranial stent implantation. (authors)

  20. The management of unimplantable stent during endovascular procedure:report of three cases

    International Nuclear Information System (INIS)

    Xiong Jiang; Wang Lijun; Guo Wei; Liu Xiaoping; Yin Tai; Jia Xin; Ma Xiaohui; Liu Meng; Zhang Hongpeng; Zhang Minhong

    2010-01-01

    Objective: To summarize the experience of dealing with the difficulty of the stent implantation encountered in the endovascular procedure. Methods: The causes of unimplantable stent encountered in the endovascular procedure included the delivery system entraping due to the stenosis and shrinking of peripheral self-expandable stent, the balloon expandable stent implantation and retrievement failure due to the rupture-balloon or stent edge opening, and the delivery system entraping due to aortic stent graft for aorta kinking. The balloon dilation for the stenosis and shrinking stent, the large caliber introducer sheath for removal of the rupture-balloon and edge opening, the expandable stent and balloon-assisted delivery system retrieve were used to solve the above three dilemma of unimplantable stent occurred in the endovascular procedure. Results: These three dilemma of stent unimplantable problem in the endovascular therapy were solved by endovascular method while little additional incision injury was added to the patients. Conclusion: For solving stent unimplantable problem the endovascular technique is the method of first choice, nevertherless, it is very important for the operator to be highly skilled in manipulating endovascular procedure. (authors)

  1. Timing of silicone stent removal in patients with post-tuberculosis bronchial stenosis

    Directory of Open Access Journals (Sweden)

    Jung Seop Eom

    2013-01-01

    Full Text Available Context: In patients with post-tuberculosis bronchial stenosis (PTBS, the severity of bronchial stenosis affects the restenosis rate after the silicone stent is removed. In PTBS patients with incomplete bronchial obstruction, who had a favorable prognosis, the timing of stent removal to ensure airway patency is not clear. Aims: We evaluated the time for silicone stent removal in patients with incomplete PTBS. Settings and Design: A retrospective study examined PTBS patients who underwent stenting and removal of a silicone stent. Methods: Incomplete bronchial stenosis was defined as PTBS other than total bronchial obstruction, which had a luminal opening at the stenotic segment on bronchoscopic intervention. The duration of stenting was defined as the interval from stent insertion to removal. The study included 44 PTBS patients and the patients were grouped at intervals of 6 months according to the duration of stenting. Results: Patients stented for more than 12 months had a significantly lower restenosis rate than those stented for less than 12 months (4% vs. 35%, P = 0.009. Multiple logistic regression revealed an association between stenting for more than 12 months and a low restenosis rate (odds ratio 12.095; 95% confidence interval 1.097-133.377. Moreover, no restenosis was observed in PTBS patients when the stent was placed more than 14 months previously. Conclusions: In patients with incomplete PTBS, stent placement for longer than 12 months reduced restenosis after stent removal.

  2. Transtracheal single-point stent fixation in posttracheotomy tracheomalacia under cone-beam computer tomography guidance by transmural suturing with the Berci needle - a perspective on a new tool to avoid stent migration of Dumon stents.

    Science.gov (United States)

    Hohenforst-Schmidt, Wolfgang; Linsmeier, Bernd; Zarogoulidis, Paul; Freitag, Lutz; Darwiche, Kaid; Browning, Robert; Turner, J Francis; Huang, Haidong; Li, Qiang; Vogl, Thomas; Zarogoulidis, Konstantinos; Brachmann, Johannes; Rittger, Harald

    2015-01-01

    Tracheomalacia or tracheobronchomalacia (TM or TBM) is a common problem especially for elderly patients often unfit for surgical techniques. Several surgical or minimally invasive techniques have already been described. Stenting is one option but in general long-time stenting is accompanied by a high complication rate. Stent removal is more difficult in case of self-expandable nitinol stents or metallic stents in general in comparison to silicone stents. The main disadvantage of silicone stents in comparison to uncovered metallic stents is migration and plugging. We compared the operation time and in particular the duration of a sufficient Dumon stent fixation with different techniques in a patient with severe posttracheotomy TM and strongly reduced mobility of the vocal cords due to Parkinson's disease. The combined approach with simultaneous Dumon stenting and endoluminal transtracheal externalized suture under cone-beam computer tomography guidance with the Berci needle was by far the fastest approach compared to a (not performed) surgical intervention, or even purely endoluminal suturing through the rigid bronchoscope. The duration of the endoluminal transtracheal externalized suture was between 5 minutes and 9 minutes with the Berci needle; the pure endoluminal approach needed 51 minutes. The alternative of tracheobronchoplasty was refused by the patient. In general, 180 minutes for this surgical approach is calculated. The costs of the different approaches are supposed to vary widely due to the fact that in Germany 1 minute in an operation room costs on average approximately 50-60€ inclusive of taxes. In our own hospital (tertiary level), it is nearly 30€ per minute in an operation room for a surgical approach. Calculating an additional 15 minutes for patient preparation and transfer to wake-up room, therefore a total duration inside the investigation room of 30 minutes, the cost per flexible bronchoscopy is per minute on average less than 6€. Although

  3. Stenting of the Lower Gastrointestinal Tract: Current Status

    International Nuclear Information System (INIS)

    Katsanos, Konstantinos; Sabharwal, Tarun; Adam, Andreas

    2011-01-01

    Colon obstruction due to colorectal cancer is a major surgical emergency. Patients with acute bowel obstruction are usually poor surgical candidates with 10–20% operative mortality and 40–50% operative morbidity rates. Colorectal stenting is an image-guided, minimally invasive procedure, and typical indications include either palliation of inoperable malignant disease or temporary bowel decompression as a bridge to surgery. Colorectal stenting allows the patient to recover before definite elective surgical resection, reducing perioperative morbidity and mortality, overall hospital stay, and associated health care costs. Palliative stenting improves quality of life compared to surgery. A concise review is provided of contemporary stenting practice of the lower gastrointestinal tract, the colon in particular, and both palliative and preoperative adjuvant procedures are evaluated in terms of relevant patient oncology, insertion technique, available stent designs, technical and clinical outcomes, associated complications, and cost–benefit analysis.

  4. Direct implantation of rapamycin-eluting stents with bioresorbable drug carrier technology utilising the Svelte coronary stent-on-a-wire: the DIRECT II study.

    Science.gov (United States)

    Verheye, Stefan; Khattab, Ahmed A; Carrie, Didier; Stella, Pieter; Slagboom, Ton; Bartunek, Jozef; Onuma, Yoshinobu; Serruys, Patrick W

    2016-08-05

    Our aim was to demonstrate the safety and efficacy of the Svelte sirolimus-eluting coronary stent-on-a-wire Integrated Delivery System (IDS) with bioresorbable drug coating compared to the Resolute Integrity zotarolimus-eluting stent with durable polymer in patients with de novo coronary artery lesions. Direct stenting, particularly in conjunction with transradial intervention (TRI), has been associated with reduced bleeding complications, procedure time, radiation exposure and contrast administration compared to conventional stenting with wiring and predilatation. The low-profile Svelte IDS is designed to facilitate TRI and direct stenting, reducing the number of procedural steps, time and cost associated with coronary stenting. DIRECT II was a prospective, multicentre trial which enrolled 159 patients to establish non-inferiority of the Svelte IDS versus Resolute Integrity using a 2:1 randomisation. The primary endpoint was angiographic in-stent late lumen loss (LLL) at six months. Target vessel failure (TVF), as well as secondary clinical endpoints, will be assessed annually up to five years. At six months, in-stent LLL was 0.09±0.31 mm in the Svelte IDS group compared to 0.13±0.27 mm in the Resolute Integrity group (p<0.001 for non-inferiority). TVF at one year was similar across the Svelte IDS and Resolute Integrity groups (6.5% vs. 9.8%, respectively). DIRECT II demonstrated the non-inferiority of the Svelte IDS to Resolute Integrity with respect to in-stent LLL at six months. Clinical outcomes at one year were comparable between the two groups.

  5. Routine short-term ureteral stent in living donor renal transplantation: introduction of a simple stent removal technique without using anesthesia and cystoscope.

    Science.gov (United States)

    Dong, J; Lu, J; Zu, Q; Yang, S; Sun, S; Cai, W; Zhang, L; Zhang, X

    2011-12-01

    We evaluated routine short-time insertion of ureteral stent in living donor renal transplant at a single center. It was easy to remove the stent without cystoscopy and anesthesia. Between October 2007 and July 2010, a single surgeon performed 76 living donor renal transplantations at one institute. All recipients underwent extravesical ureteroneocystostomy with a 2-0 silk suture passed through the venting side hole of the double-J stent into the bladder; a quadruple knot prevented the suture's slippage or distraction from the stent. After removal of the indwelling catheter at 5 days posttransplantation, the 2-0 silk passed with the urinary stream within 72 hours. The double-J stent was removed at 7 to 10 (mean 8.4) days after kidney transplantation by pulling the 2-0 silk out of the urethral orifice without anesthesia or cystoscopy. There was only one case of stenosis, which was resolved by surgery. No patient developed urinary leakage. There were three episodes of urinary tract infection in 70 patients during first 6 months' follow-up. Routine short-term stenting is a safe and effective technique in living donor renal transplantation. Removal of the stent is feasible without cystoscopy or anesthesia. Copyright © 2011 Elsevier Inc. All rights reserved.

  6. Very late stent thrombosis with second generation drug eluting stents compared to bare metal stents: Network meta-analysis of randomized primary percutaneous coronary intervention trials.

    Science.gov (United States)

    Philip, Femi; Stewart, Susan; Southard, Jeffrey A

    2016-07-01

    The relative safety of drug-eluting stents (DES) and bare-metal stents (BMS) in primary percutaneous coronary intervention (PPCI) in ST elevation myocardial infarction (STEMI) continues to be debated. The long-term clinical outcomes between second generation DES and BMS for primary percutaneous coronary intervention (PCI) using network meta-analysis were compared. Randomized controlled trials comparing stent types (first generation DES, second generation DES, or BMS) were considered for inclusion. A search strategy used Medline, Embase, Cochrane databases, and proceedings of international meetings. Information about study design, inclusion criteria, and sample characteristics were extracted. Network meta-analysis was used to pool direct (comparison of second generation DES to BMS) and indirect evidence (first generation DES with BMS and second generation DES) from the randomized trials. Twelve trials comparing all stents types including 9,673 patients randomly assigned to treatment groups were analyzed. Second generation DES was associated with significantly lower incidence of definite or probable ST (OR 0.59, 95% CI 0.39-0.89), MI (OR 0.59, 95% CI 0.39-0.89), and TVR at 3 years (OR 0.50: 95% CI 0.31-0.81) compared with BMS. In addition, there was a significantly lower incidence of MACE with second generation DES versus BMS (OR 0.54, 95% CI 0.34-0.74) at 3 years. These were driven by a higher rate of TVR, MI and stent thrombosis in the BMS group at 3 years. There was a non-significant reduction in the overall and cardiac mortality [OR 0.83, 95% CI (0.60-1.14), OR 0.88, 95% CI (0.6-1.28)] with the use of second generation DES versus BMS at 3 years. Network meta-analysis of randomized trials of primary PCI demonstrated lower incidence of MACE, MI, TVR, and stent thrombosis with second generation DES compared with BMS. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  7. Fully covered stents versus partially covered stents for palliative treatment of esophageal cancer: Is there a difference?

    Science.gov (United States)

    Alonso Lárraga, J O; Flores Carmona, D Y; Hernández Guerrero, A; Ramírez Solís, M E; de la Mora Levy, J G; Sánchez Del Monte, J C

    2018-02-26

    Malignant dysphagia is difficulty swallowing resulting from esophageal obstruction due to cancer. The goal of palliative treatment is to reduce the dysphagia and improve oral dietary intake. Self-expandable metallic stents are the current treatment of choice, given that they enable the immediate restoration of oral intake. The aim of the present study was to describe the results of using totally covered and partially covered esophageal stents for palliating esophageal cancer. A retrospective study was conducted on patients with inoperable esophageal cancer treated with self-expandable metallic stents. The 2 groups formed were: group A, which consisted of patients with a fully covered self-expandable stent (SX-ELLA ® ), and group B, which was made up of patients with a partially covered self-expandable stent (Ultraflex ® ). Of the 69-patient total, 50 were included in the study. Group A had 19 men and 2 women and their mean age was 63.6 years (range 41-84). Technical success was achieved in 100% (n=21) of the cases and clinical success in 90.4% (n=19). Group B had 24 men and 5 women and their mean age was 67.5 years (range 43-92). Technical success was achieved in 100% (n=29) of the cases and clinical success in 89.6% (n=26). Complications were similar in both groups (33.3 vs. 51.7%). There was no difference between the 2 types of stent for the palliative treatment of esophageal cancer with respect to technical success, clinical success, or complications. Copyright © 2018 Asociación Mexicana de Gastroenterología. Publicado por Masson Doyma México S.A. All rights reserved.

  8. Results of the new nitinol self-expandable stents for distal biliary structures

    NARCIS (Netherlands)

    Smits, M.; Huibregtse, K.; Tytgat, G.

    1995-01-01

    The nitinol stent is a self-expandable spiral stent made of nickel-titanium alloy. We performed a pilot study to evaluate the method of stent insertion and stent efficacy. Twenty-eight patients with irresectable malignancy had nitinol stents inserted for obstructive jaundice due to distal biliary

  9. Development of Biliary and Enteral Stents by the Korean Gastrointestinal Endoscopists

    Directory of Open Access Journals (Sweden)

    Chan Sup Shim

    2016-03-01

    Full Text Available Stenting in the gastrointestinal tract is a common procedure used for palliation of obstruction in the enteral and biliary tract. Today, stenting of malignant and benign strictures is performed at almost every major tertiary hospital in Korea. Moreover, Korea has become a major global supplier of cutting edge technology in the field of self-expanding metal stents. However, the history of stenting in Korea is relatively short and was far behind that of other nations such as Japan and Germany. The authors are humbled and gratified to have been able to observe the development and application of these stents in Korea, first hand. In this article, the authors review the overall history of stenting with a specific focus on the development of stenting in Korea. The development of esophageal, gastroduodenal, biliary, and colonic stents in Korea are reviewed in this article from a chronological and historical point of view, and a personal account of some of the significant moments of stent development in Korea are described.

  10. New ischaemic brain lesions on MRI after stenting or endarterectomy for symptomatic carotid stenosis: a substudy of the International Carotid Stenting Study (ICSS)

    NARCIS (Netherlands)

    Bonati, Leo H.; Jongen, Lisa M.; Haller, Sven; Flach, H. Zwenneke; Dobson, Joanna; Nederkoorn, Paul J.; Macdonald, Sumaira; Gaines, Peter A.; Waaijer, Annet; Waajier, Annet; Stierli, Peter; Jäger, H. Rolf; Lyrer, Philippe A.; Kappelle, L. Jaap; Wetzel, Stephan G.; van der Lugt, Aad; Mali, Willem P.; Brown, Martin M.; van der Worp, H. Bart; Engelter, Stefan T.; Koelemaij, M. J. W.; Majoie, C. B. L. M.; Reekers, J. A. A.; Roos, Y. B. W. E. M.; Flach, H. Z.; Hendriks, J. M.; Koudstaal, P. J.; Pattynama, P. M. T.; van Dijk, L. C.; van Sambeek, M. R. H. M.; van der Lugt, A.; van Urk, H.; Verhagen, H. J. M.; de Borst, G. J.; de Kort, G. A. P.; Jongen, L. M.; Kappelle, L. J.; Lo, T. H.; Mali, W. P. Th M.; Moll, F. L.; van der Worp, H. B.; Bonati, L. H.; Engelter, S. T.; Fluri, F.; Haller, S.; Jacob, A. L.; Kirsch, E.; Lyrer, P. A.; Radue, E.-W.; Stierli, P.

    2010-01-01

    BACKGROUND: The International Carotid Stenting Study (ICSS) of stenting and endarterectomy for symptomatic carotid stenosis found a higher incidence of stroke within 30 days of stenting compared with endarterectomy. We aimed to compare the rate of ischaemic brain injury detectable on MRI between the

  11. Analysis of trends and prospects regarding stents for human blood vessels.

    Science.gov (United States)

    Lee, Jeong Hee; Kim, Eung Do; Jun, Eun Jung; Yoo, Hyoung Sun; Lee, Joon Woo

    2018-01-01

    The purpose of this paper is to provide technology trends and information regarding market and prospects in stents used for human blood vessels in Korea and the world.A stent is a medical device in the form of a cylindrical metal net used to normalize flow when blood or other bodily fluids such as biliary fluids are obstructed in blood vessels, gastrointestinal tracts, etc. by inserting the stent into a narrowed or clogged area. Stents are classified into vascular and non-vascular stents. The coronary artery stent is avascular stent that is used for coronary atherosclerosis.The demand is increasing for stents to treat diseases such as those affecting the heart and blood vessels of elderly and middle-aged patients. Due to the current shift in the demographic structure caused by an aging society, the prospect for stents seems to be very bright.The use of a stent designed to prevent acute vascular occlusion and restenosis, which is a side effect of conventional balloon angioplasty, has rapidly become popular because it can prevent acute complications and improve clinical outcomes. Since the initial release of this stent, there have been significant developments in its design, the most notable of which has been the introduction of drug-eluting stents (DES). Bioresorbable scaffolds (BRS) have the potential to introduce a paradigm shift in interventional cardiology, a true anatomical and functional "vascular restoration" instead of an artificial stiff tube encased by a persistent metallic foreign body. Data for this research were gathered from primary and secondary sources as well as the databases of the Korea Institute of Science Technology Information (KISTI) located in Seoul, Korea like KISTI Market Report. The sources used for primary research included the databases available from the Korea Institute of Science Technology Information, past industry research services/studies, economic and demographic data, and trade and industry journals. Secondary research was used

  12. Dedicated bifurcation stents

    Directory of Open Access Journals (Sweden)

    Ajith Ananthakrishna Pillai

    2012-03-01

    Full Text Available Bifurcation percutaneous coronary intervention (PCI is still a difficult call for the interventionist despite advancements in the instrumentation, technical skill and the imaging modalities. With major cardiac events relate to the side-branch (SB compromise, the concept and practice of dedicated bifurcation stents seems exciting. Several designs of such dedicated stents are currently undergoing trials. This novel concept and pristine technology offers new hope notwithstanding the fact that we need to go a long way in widespread acceptance and practice of these gadgets. Some of these designs even though looks enterprising, the mere complex delivering technique and the demanding knowledge of the exact coronary anatomy makes their routine use challenging.

  13. Colorectal Stenting in Malignant Large Bowel Obstruction: The Learning Curve

    Directory of Open Access Journals (Sweden)

    D. Williams

    2011-01-01

    Full Text Available Aim. Self-expanding metal stents (SEMSs are increasingly used for the palliation of metastatic colorectal cancer and as a bridge to surgery for obstructing tumours. This case series analyses the learning curve and changes in practice of colorectal stenting over a three year period. Methods. A study of 40 patients who underwent placement of SEMS for the management of colorectal cancer. Patients spanned the learning curve of a single surgeon endoscopist. Results. Technical success rates increased from 82% initially, using an average of 1.7 stents per procedure, to a 94% success rate where all patients were stented using a single stent. There has been a change in practice from elective palliative stenting toward emergency preoperative stenting. Conclusion. There is a steep learning curve for the use of SEMS in the management of malignant colorectal bowel obstruction. We suggest that at least 20 cases are required for an operator to be considered experienced.

  14. Incidence of bacterial colonisation after indwelling of double-J ureteral stent

    Directory of Open Access Journals (Sweden)

    Hasan Riza Aydin

    2016-01-01

    Full Text Available Objective: To determine the bacterial colonisation after double-J stent use and the risk factors for bacteriuria linked to the stent. Materials and Methods: A total of 102 patients (61 men and 41 women, mean age 47.5 ± 14.16 were examined. The stents were removed under aseptic conditions, and a urine culture was obtained before the removal of the stents. After the stents were removed, the upper, central and lower sections were separated, and washing water was sent through the stent. Results: Bacterial colonisation was found in 29.4% (30 of 102 of the stents. The most frequently observed microorganisms were determined as staphylococcus, coagulase negative (8 of 30 and E. coli (5 of 30. The washing fluid used to clean the interior of the catheter produced pathogens in 8 patients (7.8%, and these pathogens were observed to be the same microorganisms that colonised the outside of the stent. There was no statistical difference between the patients with colonisation and those without in terms of age, gender, duration of stenting and reason for stent insertion. Conclusions: Though stent colonisation does not always entail symptomatic urinary tract infections, as shown in our study, the pathogens in the urine culture are the same as those colonising the stent, confirming the reality that colonisation is the main factor in these events. Additionally, according to our study, significant colonisation may be found in the first 3 weeks, contrary to the literature, causing us to consider that urinary tract infections may develop even in the early period.

  15. Magnetic resonance imaging of stents. Quantitative in vitro examination at 3 Tesla

    International Nuclear Information System (INIS)

    Reinhardt, Julia; Fachhochschule Jena; Nguyen-Trong, Thien-Hoa; Haehnel, Stefan; Bellemann, Matthias E.; Heiland, Sabine; Neurologische Universitaetsklinik Heidelberg

    2009-01-01

    The aim of this study was to qualitatively and quantitatively study MR artifacts of various stents on the basis of in vitro experiments. We were particularly interested whether sequence type and orientation of the stent with respect to the static magnetic field influences the artifact. We examined 18 stents of different material (nitinol, stainless steel, cobalt alloy), different design of the stent meshes (AccuLink, OmniLink, DynaLink, Xact, Protoge, Wallstent Monorail), different diameter (5-10 mm) and different length (18-58 mm) with a turbo spin echo (TSE), a 2D-fast low angle shot (FLASH) and a 3D-FLASH sequence. The MR images were examined qualitatively with respect to possible artifacts. Furthermore we examined the MR data quantitatively: The contrast-noise-ratio (CNR) was determined both within the stent and outside (within the tube); based on these values we calculated the transparency factor P, furthermore we calculated the apparent vascular lumen within the tube and within the stent. The stents made of stainless steel and cobalt alloy displayed severe susceptibility artifacts. Therefore the vessel lumen within the stent could not be assessed. The nitinol stents showed different artifact patterns: The AccuLink and DynaLink stents showed less artifacts compared to the Xact and Protoge stents. Besides the susceptibility artifacts we found artifacts due to RF shielding by the stent mesh, particularly in TSE sequences. A MR control of patients after stenting is possible and may yield diagnostic information when using the AccuLink or DynaLink stents. However, it is important to make sure that the stent is MR safe for the field strength used for the examination. (orig.)

  16. Modelling and simulating in-stent restenosis with complex automata

    NARCIS (Netherlands)

    Hoekstra, A.G.; Lawford, P.; Hose, R.

    2010-01-01

    In-stent restenosis, the maladaptive response of a blood vessel to injury caused by the deployment of a stent, is a multiscale system involving a large number of biological and physical processes. We describe a Complex Automata Model for in-stent restenosis, coupling bulk flow, drug diffusion, and

  17. Differentiated analysis of an everolimus-eluting stent and a paclitaxel-eluting stent among higher risk subgroups for restenosis: results from the SPIRIT II trial.

    Science.gov (United States)

    Khattab, Ahmed A; Richardt, Gert; Verin, Vitali; Kelbaek, Henning; Macaya, Carlos; Berland, Jacques; Miquel-Hebert, Karine; Dorange, Cécile; Serruys, Patrick W

    2008-03-01

    Restenosis is higher among certain subpopulations when subjected to percutaneous coronary interventions even when using drug-eluting stents. The randomised SPIRIT II trial demonstrated the superiority of the XIENCE V Everolimus Eluting Coronary Stent System over the TAXUS Paclitaxel-Eluting Stent System in terms of in-stent late loss at six months among 300 patients treated for de novo native coronary artery lesions. In this post-hoc analysis of SPIRIT II we focused on six-month angiographic outcomes of diabetic patients (n=69), left anterior descending arteries (n=149), long lesions >20 mm (n=43), small vessels B2 and C lesions (n=233). In-stent late loss was consistently less among all subgroups when treated by everolimus-eluting stents compared to paclitaxel-eluting stents: diabetics 0.15+/-0.26 mm versus 0.39+/-0.34 mm, p=0.006; LAD 0.12+/-0.23 mm versus 0.44+/-0.37 mm, pB2/C lesions 0.12+/-0.31 mm versus 0.36+/-0.36 mm, pSPIRIT II trial population.

  18. Interdisciplinary interventional therapy for tracheobronchial stenosis with modern metal net stents

    International Nuclear Information System (INIS)

    Rieger, J.; Linsenmaier, U.; Fedorowski, A.; Pfeifer, K.J.; Hautmann, H.; Huber, R.M.

    2002-01-01

    Study objectives: Assessment of the therapeutic potential of tracheobronchial stenting for obstructive tracheobronchial disease, in-vivo comparison of different stent types and development of helpful criteria for choosing the suitable stent type. Material and Methods: Prospective case analysis. Between 1993 and 1999 53 stents were implanted into the tracheobronchial system of 39 consecutive patients with benign or malignant airway obstruction. Every single stent (26 Strecker Stents, 18 Wallstents, 6 Accuflex Nitinolstents, 1 Dumon-, 1 Ruesch- and 1 Palmazstent) was recorded in an unified database. Analysis comprised clinical effectiveness, lung function if possible, relevant complications and radiologic follow-up parameters. The probability of their remaining within the tracheobronchial system, of their remaining undislocated and uncompressed was calculated using Kaplan-Meier analysis for three stent types. Results: Stent placement proved itself to be an effective treatment in 86% of the patients. Resistance could be normalized in 9/9 patients. Kaplan-Meier analysis clearly revealed a higher probability for the Wall- and Nitinolstent to remain within the tracheobronchial system and to remain uncompressed. Dislocation also occurred more rarely. Explanation of the Wallstent, however, if desired, was much more difficult compared to the Strecker stent. The Wallstent also occasionally led to the formation of granulation tissue especially at the proximal stent end and, as such, required reintervention. (orig.) [de

  19. Undilatable Stent Neoatherosclerosis Treated with Ad Hoc Rotational Atherectomy

    Directory of Open Access Journals (Sweden)

    Michael Koutouzis

    2017-01-01

    Full Text Available A middle age woman with known ischemic heart disease and old stents in proximal left anterior descending coronary artery (LAD was admitted to Coronary Care Unit with acute coronary syndrome. The coronary angiography showed one vessel disease with significant restenosis within the previously implanted stents. The lesion was tough and remained undilatable despite high pressure balloon inflation. Eventually, the balloon ruptured creating a massive dissection of the LAD beginning immediately after the distal part of the undilatable lesion. We proceeded with a challenging ad hoc rotational atherectomy of the lesion and finally stenting of the lesion. In-stent restenosis many years after stent implantation is considered to be mainly due to neoatheromatosis compared to intimal hyperplasia, making lesion treatment more difficult and unpredictable.

  20. Comparison of Self-Expanding Polyethylene Terephthalate and Metallic Stents Implanted in Porcine Iliac Arteries

    International Nuclear Information System (INIS)

    Wilczek, Krzysztof; Scheerder, Ivan de; Wang Kai; Verbeken, Eric; Piessens, Jan

    1996-01-01

    Purpose: Comparison of the biocompatibility of self-expanding polyethylene terephthalate (PET) stents with self-expanding metallic stents (Wallstents). Methods: Diameter- and length-matched PET stents and Wallstents were symmetrically implanted in the paired iliac arteries of 13 crossbred domestic swine. Stent deployment was studied angiographically and with intravascular ultrasound immediately after stent implantation. The angiographic stented lumen diameter was measured using quantitative vessel analysis before, immediately after stenting, and at 6-week follow-up. Cross-section histopathology and area morphometry were performed. Results: Immediately poststenting, intravascular ultrasound revealed proximal dislocation of 5 of the 13 PET stents, whereas all metal stents were firmly embedded at the implantation site. At 6-week follow-up, three of the remaining PET stents were totally or subtotally occluded by organized thrombus, whereas all metal stents were patent. Compared with immediately poststenting, the angiographic lumen diameter within the five remaining PET stents was reduced by 30%, and that of the metallic stents was virtually unaltered (p < 0.02). This observation was confirmed by postmortem morphometry, wherein the PET-stented vessel segments a diameter stenosis of 40% was measured vs only 9% in the metallic stents (p < 0.0001). Conclusion: PET-stent deployment is difficult to control due to the lack of radiopacity of this stent. PET stents seem to be more thrombogenic and lead to significantly more neointimal proliferation than metallic stents

  1. Self-Expandable Metallic Stent Placement in Malignant Gastric Outlet Obstruction

    Science.gov (United States)

    Ye, Bing-Wei; Lee, Kuei-Chuan; Hsieh, Yun-Cheng; Li, Chung-Pin; Chao, Yee; Hou, Ming-Chih; Lin, Han-Chieh

    2015-01-01

    Abstract Malignant gastric outlet obstruction is a late complication of intraabdominal malignancy. Self-expandable metallic stent placement has been a safe palliative treatment to relieve obstructive symptoms. We aimed to assess the efficacy and safety of metallic stents in our patients and analyzed the clinical outcome of different brands. Seventy-one patients with inoperable gastric outlet obstruction receiving WallFlex enteral stents (WallFlex group) or Bonastents (Bonastent group) since April 2010 were analyzed retrospectively. The overall technical and clinical success rates of stent placement were 100% and 93%, respectively. The baseline characteristics and clinical outcomes including procedure-related complications, restenosis, and reintervention rates were comparable between the 2 groups. However, the Bonastent group had a higher rate of stent fracture than the WallFlex group (13.3% vs 0%, P = 0.03). The mean duration of overall stent patency was 132.7 days. The mean duration of survival was 181.9 days. Resumption of regular diet or low residual diet at day 7 after stent insertion predicted stent patency (hazard ratio [HR]: 0.28, P = 0.01). Cancer with gastric origin (HR: 0.25, P = 0.045) and poststent chemotherapy (HR: 0.38, P = 0.006) predicted lower mortality; however, peritoneal carcinomatosis (HR: 3.09, P = 0.04) correlated with higher mortality. Metallic stent placement is a safe and effective method for relieving gastric outlet obstruction. Except higher rate of stent fracture in the Bonastent group, there is no significant difference in clinical outcomes between the Bonastent group and the WallFlex group. PMID:26200641

  2. Fluoroscopic guidance of retrograde exchange of ureteral stents in women.

    Science.gov (United States)

    Chang, Ruey-Sheng; Liang, Huei-Lung; Huang, Jer-Shyung; Wang, Po-Chin; Chen, Matt Chiung-Yu; Lai, Ping-Hong; Pan, Huay-Ben

    2008-06-01

    The purpose of this study was to review our experience with fluoroscopically guided retrograde exchange of ureteral stents in women. During a 48-month period, 28 women (age range, 38-76 years) were referred to our department for retrograde exchange of a ureteral stent. The causes of urinary obstruction were tumor compression in 26 patients and benign fibrotic stricture in two patients. A large-diameter snare catheter (25-mm single loop or 18- to 35-mm triple loop) or a foreign body retrieval forceps (opening width, 11.3 mm) was used to grasp the bladder end of the stent under fluoroscopic guidance. The technique entailed replacement of a patent or occluded ureteral stent with a 0.035- or 0.018-inch guidewire with or without the aid of advancement of an angiographic sheath. A total of 54 ureteral stents were exchanged with a snare catheter in 42 cases or a forceps in 12 cases. One stent misplaced too far up the ureter was replaced successfully through antegrade percutaneous nephrostomy. Ten occluded stents, including one single-J stent, were managed with a 0.018-inch guidewire in three cases, advancement of an angiographic sheath over the occluded stent into the ureter in five cases, and recannulation of the ureteral orifice with a guidewire in two cases. No complications of massive hemorrhage, ureter perforation, or infection were encountered. With proper selection of a snare or forceps catheter, retrograde exchange of ureteral stents in women can be easily performed under fluoroscopic guidance with high technical success and a low complication rate.

  3. Outcomes of Temporary Partially Covered Stent Placement for Benign Tracheobronchial Stenosis

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Ji; Han, Xinwei, E-mail: hanxinwei2006@163.com; Wu, Gang; Jiao, Dechao; Ren, Kewei; Bi, Yonghua [The First Affiliated Hospital of Zhengzhou University, Department of Interventional Radiology (China)

    2016-08-15

    PurposeTo evaluate the intermediate outcomes of temporary partially covered tracheobronchial stenting in patients with benign tracheobronchial stenosis.Materials and MethodsWe conducted a retrospective study of patients with benign tracheobronchial stenosis who underwent stent placement. All stents were removed approximately 3 months after placement. Respiratory function was assessed using the visual analogue scale (VAS) and Karnofsky performance status scale (KPS) before and after stent placement. The lumen diameters of the stenotic lesions were measured using chest computed tomography (CT) and compared between before stent placement and after stent removal.ResultsA total of 51 stents were successfully placed in consecutive 51 patients with benign tracheobronchial stenosis. No serious complications occurred. The mean VAS and KPS scores significantly improved after stent removal (6.291 ± 0.495 and 25.352 ± 10.533, respectively) compared with those before stent placement (1.493 ± 0.504 and 60.140 ± 16.344, respectively; P < 0.05). The mean lumen transverse diameters of the stenotic site in trachea and main bronchus after stent removal (17.235 ± 3.457 and 8.993 ± 0.961 mm; 1 month post-removal; 16.353 ± 4.132 and 8.357 ± 1.082 mm; 6 months post-removal) were significantly larger than those before stent placement (7.876 ± 2.351 and 2.143 ± 0.770 mm, respectively; P < 0.05). However, the mean lumen diameters between 1 and 6 months after stent removal had no significant difference (P > 0.05).ConclusionTemporary partially covered stenting may be a safe and effective treatment for benign tracheobronchial stenosis.

  4. Physical property and MR imaging of self-expandable metallic stents

    Energy Technology Data Exchange (ETDEWEB)

    Roh, Hong Gee; Kang, Sung Gwon; Cho, Young Kook; Kim, Hyung Jin; Lim, Myung Kwan; Cho, Soon Gu; Yoh, Kyu Tong; Suh, Chang Hae [Inha Univ., College of Medicine, Seoul (Korea, Republic of)

    1998-09-01

    In order to furnish basic information prior to their use, the physical properties of various self-expandable metallic stents and their MR characteristics were evaluated. Four commercially available self-expandable metallic stents-Gianturco-the Rosch, Hanaro, Memotherm, and Wallstent-were used in this study. For evaluation of the physical properties of each, hoop strengths and changes in radii according to the degrees of longitudinal flexion were compared. Stent characteristics seen on MR images were evaluated by measuring magnetic torque and by comparing images obtained in the vascular phantom using SE T1TI, FSE T2WI, and FMPSPGR sequences. These images were analyzed with special emphasis on artifact size and the apparant shepe of the stent. Hoop strength was greatest in the Gianturco-Rosch stent, followed by the Memotherm, Hanaro, and Wallstent. When flexed in the longitudinal axis, the radius of the Hanaro and Memotherm stent decreased slightly as a larger flexion angle was applied. When this was 90 deg, however, the connection of the Gianturco-Rosch stent collapsed. In contrast, the radius of the Wallstent became larger as a larger flexion angle was applied. At the portal of the MR imaging unit, neither the Memotherm nor Wallstent showed deflection; except for a thin hyperintense rim at both ends, their images were excellent, and the lumina of these stents were also clearly seen. In contrast, the Gianturco-Rosch and Hanaro stent demonstrated large deflexion and showed a severe black-hole artifact. As a result, visualization of the stents themselves and their lumina was impossible. The Gianturco-Rosch stent showed greatrer hoop strength than the others. The Wallstent showed good longitudinal flexibility and was thought to be effective in tortuous vessels. For follow-up after placement, especially when the nonferromagnetic Memotherm and Wallstent are used, MR imaging appears to be safe and useful.=20.

  5. Bioabsorbable coronary stents--are these the next big thing in coronary angioplasty?

    Science.gov (United States)

    Balla, Sudarshan; Aggarwal, Kul; Nistala, Ravi

    2010-06-01

    The role of percutaneous coronary intervention (PCI) in the treatment of coronary artery disease has grown at an astronomical pace. Drug eluting stents (DES) offer advantages over bare metal stents (BMS) such as reduction in early in-stent restenosis rates. However, they have disadvantages like from increased late stent thrombosis when compared with BMS. Furthermore, recent data suggest endothelial dysfunction in the DES stented segments of the arteries. Currently, bioabsorbable stents are under development to avert the complications of DES such as stent thrombosis via degradation of the stent over time. The hypothetical advantage of leaving behind a natural vessel and restoring vasoreactivity may be the almost normal physiology which can be achieved after an intervention with a stent. The ABSORB and the PROGRESS AMS are two of the recent clinical trials that have looked at the outcomes of using bioabsorbable stents. So far, data from these and other studies has yielded mixed results in terms of angiographic and clinical outcomes. Newer stents such as REVA and WHISPER are presently being tested in preclinical and clinical trials. The landscape for bioabsorbable stents is constantly evolving through continued improvisation on existing technology and emergence of new technology. Large scale randomized trials are still needed with adequate long term follow-up for safety and benefits to have mainstream application in coronary artery disease, bioabsorbable stents are a promising innovation in the field of PCI. We review some of the patents and the data that is emerging on bioabsorbable stents in addition to currently ongoing clinical trials.

  6. Treatment Approaches to Urinary Stones Caused by Forgotten DJ Stents

    Directory of Open Access Journals (Sweden)

    Ergun Alma

    2015-03-01

    Full Text Available Ureteral DJ stents have been used widely for years in urology practice. With increased use, complications have been increased and forgotton stents have started to cause problems. The most common complications are early pain and irritative symptoms. Late complications are bacterial colonization and stone formation because of the biofilm covering the stents. Treatment for a forgotten stent varies on many factors, such as stent localization and stone formation. In this article, we aimed to discuss our clinic approach on two different cases in light to current literature. [Cukurova Med J 2015; 40(Suppl 1: 58-63

  7. Impact of peri-stent remodeling on restenosis: a volumetric intravascular ultrasound study.

    Science.gov (United States)

    Nakamura, M; Yock, P G; Bonneau, H N; Kitamura, K; Aizawa, T; Tamai, H; Fitzgerald, P J; Honda, Y

    2001-05-01

    Vessel remodeling is an important mechanism of late lumen loss after nonstent coronary interventions. However, its impact on in-stent restenosis has not been systematically investigated. Serial volumetric intravascular ultrasound analyses (poststent and follow-up) were performed in 55 lesions treated with a balloon-expandable stent (ACS MultiLink) using standard stent deployment techniques. The vessel volume (VV), lumen volume (LV), and volume bordered by the stent (SV) were measured using Simpson's method. The volume of plaque and neointima outside the stent (peri-stent volume, PSV) and volume of neointima within the stent (intrastent volume) were also measured. The change of each parameter during the follow-up period (follow-up minus poststent) was calculated and then divided by SV to normalize these values (designated as percent change [%]). As expected, %PSV directly correlated with %VV (Pexterior to a coronary stent occurs to a variable degree after stent implantation. There is a distinct trade-off between positive remodeling and in-stent hyperplasia: in segments in which the degree of peri-stent remodeling is less, intrastent neointimal proliferation is greater and accompanied by more significant late lumen loss.

  8. Robot-Assisted Antegrade In-Situ Fenestrated Stent Grafting

    International Nuclear Information System (INIS)

    Riga, Celia V.; Bicknell, Colin D.; Wallace, Daniel; Hamady, Mohamad; Cheshire, Nicholas

    2009-01-01

    To determine the technical feasibility of a novel approach of in-situ fenestration of aortic stent grafts by using a remotely controlled robotic steerable catheter system in the porcine model. A 65-kg pig underwent robot-assisted bilateral antegrade in-situ renal fenestration of an abdominal aortic stent graft with subsequent successful deployment of a bare metal stent into the right renal artery. A 16-mm iliac extension covered stent served as the porcine aortic endograft. Under fluoroscopic guidance, the graft was punctured with a 20-G customized diathermy needle that was introduced and kept in place by the robotic arm. The needle was exchanged for a 4 x 20 mm cutting balloon before successful deployment of the renal stent. Robot-assisted antegrade in-situ fenestration is technically feasible in a large mammalian model. The robotic system enables precise manipulation, stable positioning, and minimum instrumentation of the aorta and its branches while minimizing radiation exposure.

  9. Urethroplasty after Urethral Urolume Stent: an International Multicenter Experience.

    Science.gov (United States)

    Angulo, Javier C; Kulkarni, Sanjay; Pankaj, Joshi; Nikolavsky, Dmitriy; Suarez, Pedro; Belinky, Javier; Virasoro, Ramón; DeLong, Jessica; Martins, Francisco E; Lumen, Nicolaas; Giudice, Carlos; Suárez, Oscar A; Menéndez, Nicolás; Capiel, Leandro; López-Alvarado, Damian; Ramirez, Erick A; Venkatesan, Krishnan; Husainat, Maha M; Esquinas, Cristina; Arance, Ignacio; Gómez, Reynaldo; Santucci, Richard

    2018-05-08

    To evaluate the outcomes and factors affecting success of urethroplasty in patients with stricture recurrence after Urolume® urethral stent. Retrospective international multicenter study on patients treated with urethral reconstruction after Urolume® stent. Stricture and stent length, time between urethral stent insertion and urethroplasty, age, mode of stent retrieval, type of urethroplasty, complications and baseline and post-urethroplasty voiding parameters were analyzed. Successful outcome was defined as standard voiding, without need of any postoperative adjunctive procedure. Sixty-three patients were included. Stent was removed at urethroplasty in 61 patients. Reconstruction technique was excision and primary anastomosis in 14(22.2%), dorsal onlay buccal mucosa graft (BMG) 9(14.3%), ventral onlay BMG 6(9.5%), dorso-lateral onlay BMG 9(14.3%), ventral onlay plus dorsal inlay BMG 3(4.8%), augmented anastomosis 5(7.9%), pedicled flap urethroplasty 6(9.5%), 2-stage procedure 4(6.4%) and perineal urethrostomy 7(11.1%). Success rate was 81% at a mean 59.7+63.4months. Dilatation and/or internal urethrotomy was performed in 10(15.9%), redo-urethroplasty in 5(7.9%). Total IPSS, QoL, Qmax and PVR significantly improved (pUrethroplasty in patients with Urolume® urethral stents is a viable option of reconstruction with a high success rate and very acceptable complication rate. Numerous techniques are viable, however, urethral preservation, tine-by-tine stent extraction and use of BMG augmentation produced significantly better outcomes. Copyright © 2018 Elsevier Inc. All rights reserved.

  10. Percutaneous antegrade ureteric stent removal using a rigid alligator forceps.

    LENUS (Irish Health Repository)

    Given, M F

    2008-12-01

    To evaluate the safety and efficacy of percutaneous antegrade ureteric stent removal using a rigid alligator forceps. Twenty patients were included in our study. Indications for ureteric stent insertion included stone disease (n = 7), malignancy (n = 8) and transplant anastomotic strictures (n = 5). Stent retrieval was carried out for proximal stent placement\\/migration in seven patients and encrustation in the remaining 13. Twenty-two stents were successfully retrieved in 20 patients. There was one technical failure (5%). There were no major complications. We had four minor complications, which included nephrostomy site pain (n = 2), periprocedural sepsis (n = 1) and a small urinoma (n = 1). All patients settled with conservative management. Percutaneous radiologically guided antegrade ureteric stent removal with an alligator forceps is safe and effective, particularly when initial surgical removal has failed.

  11. Effect of cilostazol on in-stent neointimal hyperplasia after coronary artery stenting. A quantitative coronary angiography and volumetric intravascular ultrasound study

    International Nuclear Information System (INIS)

    Min, Pil-Ki; Jung, Jae-Hun; Ko, Young-Guk; Choi, Donghoon; Jang, Yangsoo; Shim, Won-Heum

    2007-01-01

    This study was designed to investigate the efficacy of cilostazol on the prevention of in-stent neointimal hyperplasia as measured by both quantitative coronary angiography (CAG) and volumetric intravascular ultrasound (IVUS). Fifty-nine patients (39 men, age 62 years) undergoing elective coronary stenting were randomly assigned to receive aspirin plus clopidogrel or ticlopidine (Group I, n=28, 30 lesions) or aspirin plus clopidogrel or ticlopidine plus cilostazol (Group II, n=31, 35 lesions). CAG and IVUS were performed and repeated at 6 months to assess the primary endpoints of minimal luminal diameter (MLD) and in-stent neointimal hyperplasia volume. Follow-up CAG was performed on all patients and follow-up IVUS study was available for 50 lesions in 48 patients (24 lesions in Group I, 26 in Group II). There were no significant differences in the baseline angiographic data between the 2 groups. At 6 months follow-up, in-stent MLD was 1.90±0.76 mm in Group I and 2.41±0.85 mm in Group II (p=0.006). Volumetric IVUS at 6 months demonstrated that in-stent intimal hyperplasia volume per stent length was 2.2±1.4 mm 3 /mm in Group I and 1.0±0.5 mm 3 /mm in Group II (p=0.001). Triple antiplatelet therapy including cilostazol seems to be more effective at preventing in-stent neointimal hyperplasia than a dual antiplatelet regimen. (author)

  12. Plastic or metal stents for benign extrahepatic biliary strictures: a systematic review

    Directory of Open Access Journals (Sweden)

    Vleggaar Frank P

    2009-12-01

    Full Text Available Abstract Background Benign biliary strictures may be a consequence of surgical procedures, chronic pancreatitis or iatrogenic injuries to the ampulla. Stents are increasingly being used for this indication, however it is not completely clear which stent type should be preferred. Methods A systematic review on stent placement for benign extrahepatic biliary strictures was performed after searching PubMed and EMBASE databases. Data were pooled and evaluated for technical success, clinical success and complications. Results In total, 47 studies (1116 patients on outcome of stent placement were identified. No randomized controlled trials (RCTs, one non-randomized comparative studies and 46 case series were found. Technical success was 98,9% for uncovered self-expandable metal stents (uSEMS, 94,8% for single plastic stents and 94,0% for multiple plastic stents. Overall clinical success rate was highest for placement of multiple plastic stents (94,3% followed by uSEMS (79,5% and single plastic stents (59.6%. Complications occurred more frequently with uSEMS (39.5% compared with single plastic stents (36.0% and multiple plastic stents (20,3%. Conclusion Based on clinical success and risk of complications, placement of multiple plastic stents is currently the best choice. The evolving role of cSEMS placement as a more patient friendly and cost effective treatment for benign biliary strictures needs further elucidation. There is a need for RCTs comparing different stent types for this indication.

  13. Magnetic Stent Removal in a Nurse-Led Clinic; a Nine-Month Experience.

    LENUS (Irish Health Repository)

    O’Connell, L

    2018-02-01

    Ureteric stents are frequently inserted post endourological procedures. However, subsequent endoscopic stent removal requires a second procedure for the patient and the availability of necessary resources. Longer duration of indwelling stents can lead to increased risk of symptoms and complications. The use of magnetic stents removed with a magnetic retrieval device (BlackStar©), offers an alternative which obviates the need for cystoscopy. We assessed the outcomes for this novel method of stent removal in our institution. A retrospective analysis was performed of all patients undergoing magnetic stent insertion and subsequent removal in a nurse-led clinic over a nine-month period. Patients were followed up with a prospective validated Ureteral Stent Symptoms Questionnaire (USSQ)3. A cost analysis was also performed. In total, 59 patients were treated using magnetic stents. The complication rate was low (6.7%). The median duration of indwelling stent was 5.8 days (range 1-11 days). Patients reported haematuria and lower urinary tract symptoms but >90% experienced no functional impairment with minimal days of employment lost (mean 0.75 days). All patients reported satisfaction with nurse-led stent removal and 97% were happy to have stents removed via this method in the future. The total financial savings were estimated at €47,790 over this period. Nurse-led removal of magnetic stents is safe and well tolerated by patients and enables expedient stent removal. It also provides a significant cost benefit and frees up valuable endoscopic resources.

  14. In vitro pharmacokinetics of sirolimus-coated stent for tracheal stenosis

    African Journals Online (AJOL)

    Further increases in sirolimus: PLGA ratio did not improve stent drug loading. A slow release of ... tracheal stent can damage the airway mucosa, and cause .... Figure 3: Cumulative drug release from sirolimus-coated stents. DISCUSSION.

  15. Transtracheal single-point stent fixation in posttracheotomy tracheomalacia under cone-beam computer tomography guidance by transmural suturing with the Berci needle – a perspective on a new tool to avoid stent migration of Dumon stents

    Science.gov (United States)

    Hohenforst-Schmidt, Wolfgang; Linsmeier, Bernd; Zarogoulidis, Paul; Freitag, Lutz; Darwiche, Kaid; Browning, Robert; Turner, J Francis; Huang, Haidong; Li, Qiang; Vogl, Thomas; Zarogoulidis, Konstantinos; Brachmann, Johannes; Rittger, Harald

    2015-01-01

    Tracheomalacia or tracheobronchomalacia (TM or TBM) is a common problem especially for elderly patients often unfit for surgical techniques. Several surgical or minimally invasive techniques have already been described. Stenting is one option but in general long-time stenting is accompanied by a high complication rate. Stent removal is more difficult in case of self-expandable nitinol stents or metallic stents in general in comparison to silicone stents. The main disadvantage of silicone stents in comparison to uncovered metallic stents is migration and plugging. We compared the operation time and in particular the duration of a sufficient Dumon stent fixation with different techniques in a patient with severe posttracheotomy TM and strongly reduced mobility of the vocal cords due to Parkinson’s disease. The combined approach with simultaneous Dumon stenting and endoluminal transtracheal externalized suture under cone-beam computer tomography guidance with the Berci needle was by far the fastest approach compared to a (not performed) surgical intervention, or even purely endoluminal suturing through the rigid bronchoscope. The duration of the endoluminal transtracheal externalized suture was between 5 minutes and 9 minutes with the Berci needle; the pure endoluminal approach needed 51 minutes. The alternative of tracheobronchoplasty was refused by the patient. In general, 180 minutes for this surgical approach is calculated. The costs of the different approaches are supposed to vary widely due to the fact that in Germany 1 minute in an operation room costs on average approximately 50–60€ inclusive of taxes. In our own hospital (tertiary level), it is nearly 30€ per minute in an operation room for a surgical approach. Calculating an additional 15 minutes for patient preparation and transfer to wake-up room, therefore a total duration inside the investigation room of 30 minutes, the cost per flexible bronchoscopy is per minute on average less than 6

  16. Ureteric stent dwelling time: a risk factor for post-ureteroscopy sepsis.

    Science.gov (United States)

    Nevo, Amihay; Mano, Roy; Baniel, Jack; Lifshitz, David A

    2017-07-01

    To evaluate the association between stent dwelling time and sepsis after ureteroscopy, and identify risk factors for sepsis in this setting. The prospectively collected database of a single institution was queried for all patients who underwent ureteroscopy for stone extraction between 2010 and 2016. Demographic, clinical, preoperative and operative data were collected. The primary study endpoint was sepsis within 48 h of ureteroscopy. Logistic regressions were performed to identify predictors of post-ureteroscopy sepsis in the ureteroscopy cohort and specifically in patients with prior stent insertion. Between October 2010 and April 2016, 1 256 patients underwent ureteroscopy for stone extraction. Risk factors for sepsis included prior stent placement, female gender and Charlson comorbidity index. A total of 601 patients had a ureteric stent inserted before the operation and were included in the study cohort, in which the median age was 56 years, 90 patients were women (30%), and 97 patients were treated for positive preoperative urine cultures (16.1%). Postoperative sepsis, Sepsis rates after stent dwelling times of 1, 2, 3 and >3 months were 1, 4.9, 5.5 and 9.2%, respectively. On multivariate analysis, stent dwelling time, stent insertion because of sepsis, and female gender were significantly associated with post-ureteroscopy sepsis in patients with prior stent placement. Patients who undergo ureteroscopy after ureteric stent insertion have a higher risk of postoperative sepsis. Prolonged stent dwelling time, sepsis as an indication for stent insertion, and female gender are independent risk factors. Stent placement should be considered cautiously, and if inserted, ureteroscopy should be performed within 1 month. © 2017 The Authors BJU International © 2017 BJU International Published by John Wiley & Sons Ltd.

  17. Estrategias de reperfusión usadas en pacientes con síndrome coronario agudo con elevación persistente del segmento ST en un hospital general: Reperfusion strategies in patients with acute coronary syndrome and persistent ST-segment elevation in a general hospital

    Directory of Open Access Journals (Sweden)

    Luis Borda-Velásquez

    2015-01-01

    Full Text Available Objetivos: Conocer las estrategias de reperfusión en pacientes con síndrome coronario agudo ST elevado (SCASTE atendidos en el departamento de emergencia de un hospital general, y determinar el tiempo para realizar dichas estrategias a través de los tiempos puerta-aguja (P-A, puerta-balón (P-B, electrocardiograma (ECG y total de isquemia. Material y métodos: Estudio retrospectivo transversal en pacientes con diagnóstico de SCASTE en el Hospital Nacional Cayetano Heredia (HNCH desde el 1° de enero de 2011 al 31 de enero de 2013. Se registraron las características demográficas y clínicas, tiempos de reperfusión miocárdica, de síntomas, para toma de ECG. Los factores asociados fueron analizados por análisis bivariado. Resultados: Cuarenta y cinco pacientes fueron elegibles. La edad media fue 60,5 ± 10,98 años, 88,8% fueron varones. El tiempo medio de hospitalización fue 9,79 ± 10,36 días. Se encontró obesidad (IMC ≥ 30 en 61,3%; hipertensión en 40,9%: tabaquismo en 43,1%; y diabetes mellitus II (DM II en 25%. El tiempo medio P-A de 57 ± 54,1 minutos; en 28,1% se administró el agente trombolítico antes de los 30 minutos. Angioplastia fue realizada en un paciente con un tiempo P-B de 440 minutos. El tiempo total de isquemia (TTI medio fue 244 ± 143,9 minutos. Conclusiones: Las estrategias de reperfusión fueron usadas en 71,1% de pacientes, siendo trombólisis la más usada; sin embargo, el tiempo P-A se encontró fuera del rango óptimo

  18. Improved safety and reduction in stent thrombosis associated with biodegradable polymer-based biolimus-eluting stents versus durable polymer-based sirolimus-eluting stents in patients with coronary artery disease: final 5-year report of the LEADERS (Limus Eluted From A Durable Versus ERodable Stent Coating) randomized, noninferiority trial.

    Science.gov (United States)

    Serruys, Patrick W; Farooq, Vasim; Kalesan, Bindu; de Vries, Ton; Buszman, Pawel; Linke, Axel; Ischinger, Thomas; Klauss, Volker; Eberli, Franz; Wijns, William; Morice, Marie Claude; Di Mario, Carlo; Corti, Roberto; Antoni, Diethmar; Sohn, Hae Y; Eerdmans, Pedro; Rademaker-Havinga, Tessa; van Es, Gerrit-Anne; Meier, Bernhard; Jüni, Peter; Windecker, Stephan

    2013-08-01

    This study sought to report the final 5 years follow-up of the landmark LEADERS (Limus Eluted From A Durable Versus ERodable Stent Coating) trial. The LEADERS trial is the first randomized study to evaluate biodegradable polymer-based drug-eluting stents (DES) against durable polymer DES. The LEADERS trial was a 10-center, assessor-blind, noninferiority, "all-comers" trial (N = 1,707). All patients were centrally randomized to treatment with either biodegradable polymer biolimus-eluting stents (BES) (n = 857) or durable polymer sirolimus-eluting stents (SES) (n = 850). The primary endpoint was a composite of cardiac death, myocardial infarction (MI), or clinically indicated target vessel revascularization within 9 months. Secondary endpoints included extending the primary endpoint to 5 years and stent thrombosis (ST) (Academic Research Consortium definition). Analysis was by intention to treat. At 5 years, the BES was noninferior to SES for the primary endpoint (186 [22.3%] vs. 216 [26.1%], rate ratio [RR]: 0.83 [95% confidence interval (CI): 0.68 to 1.02], p for noninferiority 1 year) and associated composite clinical outcomes. (Limus Eluted From A Durable Versus ERodable Stent Coating [LEADERS] trial; NCT00389220). Copyright © 2013 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  19. Safety of endoscopic removal of self-expandable stents after treatment of benign esophageal diseases.

    Science.gov (United States)

    van Halsema, Emo E; Wong Kee Song, Louis M; Baron, Todd H; Siersema, Peter D; Vleggaar, Frank P; Ginsberg, Gregory G; Shah, Pari M; Fleischer, David E; Ratuapli, Shiva K; Fockens, Paul; Dijkgraaf, Marcel G W; Rando, Giacomo; Repici, Alessandro; van Hooft, Jeanin E

    2013-01-01

    Temporary placement of self-expandable stents has been increasingly used for the management of benign esophageal diseases. To evaluate the safety of endoscopic removal of esophageal self-expandable stents placed for the treatment of benign esophageal diseases. Multicenter retrospective study. Six tertiary care centers in the United States and Europe. A total of 214 patients with benign esophageal diseases undergoing endoscopic stent removal. Endoscopic stent removal. Endoscopic techniques for stent removal, time to stent removal, and adverse events related to stent removal. A total of 214 patients underwent a total of 329 stent extractions. Stents were mainly placed for refractory strictures (49.2%) and fistulae (49.8%). Of the removed stents, 52% were fully covered self-expandable metal stents (FCSEMSs), 28.6% were partially covered self-expandable metal stents (PCSEMSs), and 19.5% were self-expandable plastic stents. A total of 35 (10.6%) procedure-related adverse events were reported, including 7 (2.1%) major adverse events. Multivariate analysis revealed that use of PCSEMSs (P stent removal. Favorable factors for successful stent removal were FCSEMSs (P ≤ .012) and stent migration (P = .010). No significant associations were found for stent indwelling time (P = .145) and stent embedding (P = .194). Retrospective analysis, only tertiary care centers. With an acceptable major adverse event rate of 2.1%, esophageal stent removal in the setting of benign disease was found to be a safe and feasible procedure. FCSEMSs were more successfully removed than self-expandable plastic stents and PCSEMSs. Adverse events caused by stent removal were not time dependent. Copyright © 2013 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All rights reserved.

  20. Malignant biliary obstruction: percutaneous use of self-expandable stents

    NARCIS (Netherlands)

    Laméris, J. S.; Stoker, J.; Nijs, H. G.; Zonderland, H. M.; Terpstra, O. T.; van Blankenstein, M.; Schütte, H. E.

    1991-01-01

    A total of 83 self-expandable metallic stents were placed percutaneously in 69 patients for palliation of malignant biliary obstruction. Stent diameter was 1 cm; length, 3.5-10.5 cm. Of the 41 patients with common bile duct obstruction, 27 died 0.2-12 months (median, 3.2 months) after stent