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Sample records for stent implantation assessed

  1. 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 or resteno......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...

  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. Serial optical coherence tomography assessment of malapposed struts after everolimus-eluting stent implantation. A subanalysis from the HEAL-EES study

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    Ishida, Kohki [Cardiology Department, Cardiovascular Institute, Hospital Clínic, Institut d' Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), University of Barcelona, Barcelona (Spain); Otsuki, Shuji [Division of Cardiology, Teikyo University Hospital, Tokyo (Japan); Giacchi, Giuseppe; Ortega-Paz, Luis [Cardiology Department, Cardiovascular Institute, Hospital Clínic, Institut d' Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), University of Barcelona, Barcelona (Spain); Shiratori, Yoshitaka [Division of Cardiology, Teikyo University Hospital, Tokyo (Japan); Freixa, Xavier; Martín-Yuste, Victoria; Masotti, Mónica; Sabaté, Manel [Cardiology Department, Cardiovascular Institute, Hospital Clínic, Institut d' Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), University of Barcelona, Barcelona (Spain); Brugaletta, Salvatore, E-mail: sabrugal@clinic.ub.es [Cardiology Department, Cardiovascular Institute, Hospital Clínic, Institut d' Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), University of Barcelona, Barcelona (Spain)

    2017-01-15

    Background: Incomplete stent apposition (ISA) is related to stent thrombosis, which is a serious adverse event. We aim to assess the time-course of ISA after 2nd generation everolimus-eluting stent (EES) implantation. Methods: In HEAL-EES study, we enrolled 36 patients who underwent percutaneous coronary intervention (PCI) with EES. OCT imaging was performed at baseline and follow-up. Patients were randomized 1:1:1 into 3 groups according to the time in which follow-up was performed: group A (6-month), group B (9-month), and group C (12-month). In this subanalysis, patients who had ISA segments at baseline and/or follow-up OCT were analyzed. Result: At baseline, among 41 lesions in 36 patients, 20 lesions in 18 patients had ISA segments and were analyzed. At baseline, there were 3.0% ISA struts in group A (n = 8), 2.8% in group B (n = 4), and 4.5% in group C (n = 8). At follow-up, ISA struts were present in 0.09%, 0.16% and 0.64%; respectively in groups A, B, and C. At follow-up, there was a significant decrease in the frequency of ISA: group A 3.0% vs. 0.09% (p < 0.001), group B 2.8% vs. 0.16% (p < 0.001), and group C 4.5% vs. 0.64% (p < 0.001). In group A, there was one late acquired ISA at follow-up. Conclusions: In patients undergoing 2nd generation EES implantation, area of acute ISA assessed by OCT, was almost resolved at 6-month follow-up. - Highlights: • Time-course of incomplete stent apposition of everolimus-eluting stent was assessed. • Serial optical coherence tomography images at baseline and follow-up were evaluated. • Acute incomplete stent apposition was almost resolved as early as at 6 months.

  4. Peri-stent contrast staining, major evaginations and severe malapposition after biolimus-eluting stent implantation

    DEFF Research Database (Denmark)

    Antonsen, Lisbeth; Thayssen, Per; Jensen, Lisette Okkels

    2014-01-01

    Peri-stent contrast staining and late acquired malapposition represent pathological vessel wall healing patterns following percutaneous coronary intervention with stent implantation. Earlier studies have described these abnormal vessel wall responses commonly present after implantation of first...... after third-generation biolimus-eluting stent implantation....

  5. 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

    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...

  6. Pathological aspects of bioresorbable stent implantation.

    Science.gov (United States)

    Sanchez, Oscar D; Yahagi, Kazuyuki; Byrne, Robert A; Mori, Hiroyoshi; Zarpak, Roya; Wittchow, Eric; Foin, Nicolas; Virmani, Renu; Joner, Michael

    2015-01-01

    The treatment of obstructive coronary artery disease has been revolutionised by the advent of drug-eluting stent therapy. However, concerns remain about complications late after stent implantation including late stent thrombosis, hypersensitivity reactions and neoatherosclerosis. In this respect, the introduction of fully bioresorbable stents (BRS)--which resorb over time and leave the arterial wall free of any metal constraints--represents a potentially important disruptive technology. However, although the concept is intuitively attractive, a thorough understanding of the histopathological changes seen after BRS implantation and an appreciation of comparative changes versus existing metal stent technologies are vital to guide BRS clinical usage. In this respect, translational investigation of polymer chemistry, biomedical engineering, as well as in vitro and in vivo testing in animal models is an important undertaking. This article will review the pathological aspects of BRS implantation with a focus on acute and chronic vascular reactions derived from preclinical animal studies, including insights from in vivo imaging. Finally, potential future directions of this novel therapeutic approach will be discussed.

  7. Spectral Analysis Related to Bare-Metal and Drug-Eluting Coronary Stent Implantation

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Rose Mary Ferreira Lisboa da, E-mail: roselisboa@cardiol.br [Faculdade de Medicina da UFMG, Divinópolis, MG (Brazil); Silva, Carlos Augusto Bueno [Faculdade de Medicina da UFMG, Divinópolis, MG (Brazil); Belo Horizonte, Hospital São João de Deus, Divinópolis, MG (Brazil); Greco, Otaviano José [Belo Horizonte, Hospital São João de Deus, Divinópolis, MG (Brazil); Moreira, Maria da Consolação Vieira [Faculdade de Medicina da UFMG, Divinópolis, MG (Brazil)

    2014-08-15

    The autonomic nervous system plays a central role in cardiovascular regulation; sympathetic activation occurs during myocardial ischemia. To assess the spectral analysis of heart rate variability during stent implantation, comparing the types of stent. This study assessed 61 patients (mean age, 64.0 years; 35 men) with ischemic heart disease and indication for stenting. Stent implantation was performed under Holter monitoring to record the spectral analysis of heart rate variability (Fourier transform), measuring the low-frequency (LF) and high-frequency (HF) components, and the LF/HF ratio before and during the procedure. Bare-metal stent was implanted in 34 patients, while the others received drug-eluting stents. The right coronary artery was approached in 21 patients, the left anterior descending, in 28, and the circumflex, in 9. As compared with the pre-stenting period, all patients showed an increase in LF and HF during stent implantation (658 versus 185 ms2, p = 0.00; 322 versus 121, p = 0.00, respectively), with no change in LF/HF. During stent implantation, LF was 864 ms2 in patients with bare-metal stents, and 398 ms2 in those with drug-eluting stents (p = 0.00). The spectral analysis of heart rate variability showed no association with diabetes mellitus, family history, clinical presentation, beta-blockers, age, and vessel or its segment. Stent implantation resulted in concomitant sympathetic and vagal activations. Diabetes mellitus, use of beta-blockers, and the vessel approached showed no influence on the spectral analysis of heart rate variability. Sympathetic activation was lower during the implantation of drug-eluting stents.

  8. 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.

  9. 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.

  10. Restoration of myocardial blood flow following percutaneous coronary balloon dilatation and stent implantation: Assessment with qualitative and quantitative contrast-enhanced magnetic resonance imaging

    International Nuclear Information System (INIS)

    Sensky, P.R.; Samani, N.J.; Horsfield, M.A.; Cherryman, G.R.

    2002-01-01

    AIM: To examine the serial use of magnetic resonance imaging (MRI) to evaluate regional myocardial perfusion changes following percutaneous coronary angioplasty and stent implantation (PTCA). MATERIALS AND METHODS: Six patients with single vessel coronary artery disease (CAD) underwent contrast-enhanced first pass MRI immediately prior to (visit A) and within 7 days after (visit B) PTCA. Three sequential short axis slices were obtained after gadodiamide (Gd) bolus (0.025 mmol/kg -1 ) at rest and during adenosine. Each short axis was divided radially into eight regions of interest (ROIs). ROIs were anatomically assigned to a coronary artery territory (CAT). Stress and rest qualitative and quantitative (unidirectional extraction fraction constant (K i ); index of myocardial perfusion reserve (MPRI) = stressK i / restK i ) perfusion parameters were determined for ROI supplied by remote and stenosed/stented vessels for each visit. RESULTS: In stented ROIs the number of ROIs demonstrating normal perfusion, as opposed to reversible perfusion deficits, increased. Qualitative perfusion assessment in remote CATs was unchanged. MPRI in stenotic CATs was lower than in remote CATs at visit A (P < 0.001). Following PTCA, MPRI increased in stented CATs (P < 0.001) but was unchanged in remote CATs. CONCLUSION: Restoration of myocardial perfusion following PTCA can be delineated with qualitative and quantitative perfusion MRI. Although at present the investigation is technically complex and not perfectly sensitive or specific, MRI has the potential to be a valuable tool for patient follow-up and evaluation of revascularization strategy efficacy. Sensky, P.R. et al. (2002)

  11. Stent Fracture after Everolimus-Eluting Stent Implantation

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    Ali S. Almasood

    2011-01-01

    Full Text Available Compared with bare-metal stents, drug-eluting stents (DES have greatly reduced the risk of in-stent restenosis (ISR by inhibiting neointimal growth. Nevertheless, DES are still prone to device failure, which may lead to cardiac events. Recently, stent fracture (SF has emerged as a potential mechanism of DES failure that is associated with ISR. Stent fracture is strongly related to stent type, and prior reports suggest that deployment of sirolimus eluting stents (SES may be associated with a higher risk of SF compared to other DES. Everolimus eluting stents (EESs represent a new generation of DES with promising results. The occurrence of SF with EES has not been well established. The present paper describes two cases of EES fracture associated with ISR.

  12. Pulmonary Arterial Stent Implantation in an Adult with Williams Syndrome

    International Nuclear Information System (INIS)

    Reesink, Herre J.; Henneman, Onno D. F.; Delden, Otto M. van; Biervliet, Jules D.; Kloek, Jaap J.; Reekers, Jim A.; Bresser, Paul

    2007-01-01

    We report a 38-year-old patient who presented with pulmonary hypertension and right ventricular dysfunction due to pulmonary artery stenoses as a manifestation of Williams syndrome, mimicking chronic thromboembolic pulmonary hypertension. The patient was treated with balloon angioplasty and stent implantation. Short-term follow-up showed a good clinical result with excellent patency of the stents but early restenosis of the segments in which only balloon angioplasty was performed. These stenoses were subsequently also treated successfully by stent implantation. Stent patency was observed 3 years after the first procedure

  13. 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.

  14. Surgical stent for dental implant using cone beam CT images

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Hyung Soo; Kim, Gyu Tae; Choi, Yong Suk; Hwang, Eui Hwan [Department of Oral and Maxillofacial Radiology, School of Dentistry, Kung Hee University, Seoul (Korea, Republic of)

    2010-12-15

    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.

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

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    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.

  16. Tricuspid valved stent implantation: novel stent with a self-expandable super-absorbent polymer.

    Science.gov (United States)

    Iino, Kenji; Lozonschi, Lucian; Metzner, Anja; Marczynski-Bühlow, Martin; Renner, Jochen; Cremer, Jochen; Lutter, Georg

    2011-08-01

    Trans-catheter aortic and pulmonary valve replacement procedures can result in favorable outcomes in selected patients. The aim of this study was to investigate the functioning of a novel self-expanding valved stent with super-absorbent polymer (SAP) for minimally invasive replacement of the tricuspid valve. A newly designed nitinol stent with SAP was specially designed for the tricuspid annulus. This device was composed of right atrial anchoring elements, a left ventricular tubular stent, and a trileaflet bovine pericardial valve. The stent was coated with a waterproof material, and a pouch containing SAP for minimizing paravalvular leakage was placed beneath the atrial element. Seven pigs underwent minimally invasive off-pump tricuspid valved stent implantation. This was performed through a lower ministernotomy using a transventricular approach under transesophageal echocardiographic guidance. After 1 and 6h, a complete echocardiographic evaluation and hemodynamics (Swan-Ganz catheter) were performed. Six of seven pigs exhibited normal hemodynamics immediately after tricuspid valved stent implantation and maintained stability for the entire period of monitoring. In one pig, a part of the atrial stent elements was deployed into the right ventricle, leading to significant paravalvular leakage, and died very soon. All subsequent animals survived with good results in the observation period. Accurate positioning of the valved stent was documented in six of seven pigs. SAP expanded and filled the gap between the stent and the native annulus in all animals. Mild paravalvular leakage was found in two of the six animals. Nevertheless, the observed leakage decreased to trace levels 6h after implantation. In the additional four pigs, only trace tricuspid regurgitation was revealed. No right ventricular outflow tract obstruction was detected. Trans-apical off-pump tricuspid valved stent implantation is feasible in an acute experimental setting, and SAP may help to reduce

  17. Clopidogrel discontinuation within the first year after coronary drug-eluting stent implantation

    DEFF Research Database (Denmark)

    Thim, Troels; Johansen, Martin Berg; Chisholm, Gro Egholm

    2014-01-01

    BACKGROUND: The impact of adherence to the recommended duration of dual antiplatelet therapy after first generation drug-eluting stent implantation is difficult to assess in real-world settings and limited data are available. METHODS: We followed 4,154 patients treated with coronary drug-eluting ......BACKGROUND: The impact of adherence to the recommended duration of dual antiplatelet therapy after first generation drug-eluting stent implantation is difficult to assess in real-world settings and limited data are available. METHODS: We followed 4,154 patients treated with coronary drug......-eluting stents in Western Denmark for 1 year and obtained data on redeemed clopidogrel prescriptions and major adverse cardiovascular events (MACE, i.e., cardiac death, myocardial infarction, or stent thrombosis) from medical databases. RESULTS: Discontinuation of clopidogrel within the first 3 months after...... stent implantation was associated with a significantly increased rate of MACE at 1-year follow-up (hazard ratio (HR) 2.06; 95% confidence interval (CI): 1.08-3.93). Discontinuation 3-6 months (HR 1.29; 95% CI: 0.70-2.41) and 6-12 months (HR 1.29; 95% CI: 0.54-3.07) after stent implantation were...

  18. Sirolimus-eluting versus bare-metal stent implantation in patients with ostial lesions

    DEFF Research Database (Denmark)

    Jørgensen, Erik; Kelbæk, Henning; Kløvgaard, Lene

    2010-01-01

    To investigate the efficacy of implantation of sirolimus-eluting stents (SES) in the ostium of coronary arteries.......To investigate the efficacy of implantation of sirolimus-eluting stents (SES) in the ostium of coronary arteries....

  19. Investigation of Stent Implant Mechanics Using Linear Analytical and Computational Approach.

    Science.gov (United States)

    Yang, Hua; Fortier, Aleksandra; Horne, Kyle; Mohammad, Atif; Banerjee, Subhash; Han, Hai-Chao

    2017-03-01

    Stent implants are essential in restoring normal blood flow in atherosclerotic arteries. Recent studies have shown high failure rates of stent implants in superficial femoral artery (SFA) as a result of dynamic loading environment imposed on the stent implants by the diseased arterial wall and turbulent blood flow. There are variety of stent designs and materials currently on the market however, there is no clear understanding if specific stent design is suitable with the material that is manufactured from and if this combination can sustain the life-cycle that the stent implants need to undergo once inside the artery. Lack of studies have been presented that relate stent mechanical properties with stent geometry and material used. This study presents linear theoretical and computational modeling approach that determines stent mechanical properties with effective stiffness of the deployed stent. Effective stiffness of the stent has been accurately derived based on stent structure design and loading in axial and radial directions. A rhombus stent structure was selected for this study due to its more common use and produced by main stream manufacturers. The derived theoretical model was validated using numerical finite element modeling approach. Results from this study can lead to preliminary insight towards understanding of stent deformation based on stent geometry, material properties and artery wall pressure; and how to carefully match stent's geometry with suitable material for long life cycle, increased strength, and reliable performance of stent implants.

  20. Enhanced platelet activation following coronary stent implantation in patients on hemodialysis.

    Science.gov (United States)

    Fu, Qiang; Ishikawa, Shuichi; Yokoyama, Naoyuki; Kozuma, Ken; Takada, Kaoru; Muraki, Aki; Isshiki, Takaaki

    2010-07-01

    Hemodialysis ("HD") has been suggested as a risk factor for stent thrombosis. However, platelet function in HD patients after coronary stent implantation remains unclear. The aim of this study was to evaluate platelet function following coronary stent implantation in HD patients. A total of 10 HD and 31 non-HD patients who underwent a first coronary stent implantation were studied. All patients received 100 or 200 mg of asprin and thienopiridine (either ticlopidine 200 mg or clopidogel 75 mg) daily. Platelet function was assessed 2-6 weeks (21 ± 8 days) after stent implantation by: (1) platelet maximal aggregation, using light transmittance aggregometry; (2) platelet aggregation threshold index, which was defined as putative concentration of agonist giving 50% maximum aggregation using whole-blood aggregometry; and (3) platelet activation markers (PAC-1 and CD62p), using whole blood flow cytometry. There were no differences between the two groups in baseline and procedure characteristics, except for a greater prevalence of hypertension and calcification in the HD group. Early stent thrombosis and bleeding did not occur in either group. Although no differences in platelet maximal aggregation or whole-blood aggregation were observed, expression of PAC-1 (39.6 ± 9.1 vs 24.2 ± 13.2%) and CD62p (10.4 ± 5.5 vs 5.4 ± 2.3%) were significantly increased in the HD group compared with the non-HD group. HD patients exhibited enhanced platelet activation after coronary stent implantation, but suppression of platelet aggregation was achieved by the current dual antiplatelet therapy.

  1. Malignant Gastric and Duodenal Stenosis: Palliation by Peroral Implantation of a Self-Expanding Metallic Stent

    International Nuclear Information System (INIS)

    Pinto, Isabel T.

    1997-01-01

    Purpose: To assess the use of self-expanding metallic stents in patients with inoperable malignant antrum-pylorus-duodenal obstruction. Methods: Six patients underwent implantation of a Wallstent self-expanding metallic endoprosthesis (20 mm in five patients and 16 mm in one). In five patients a catheter (Berenstein) was introduced perorally into the stomach. A guidewire (Terumo) was introduced through the catheter and advanced through the antrum-pylorus-duodenal stenosis. The guidewire was removed and a 260-cm-long, 0.035'' superstiff guide (Amplatz) was introduced. After the catheter was removed the stent assembly was introduced. In the last patient the stent was implanted through a percutaneous gastrostomy. Results: Treatment of inoperable gastric outlet obstruction caused by tumor compression is difficult and unsatisfactory. Peroral implantation of self-expanding metallic stents resulted in successful palliative therapy of antrum-pylorus-duodenal stenosis in six patients in whom surgery was not possible because of advanced disease and poor general condition. On average, patients were able to eat during 41 days. One patient is tolerating oral intake at 3 months. Conclusion: Implantation of stents resulted in palliative relief of malignant antrum-pylorus-duodenal obstructions

  2. Clinical outcomes and prognosis of patients with stent fracture after successful drug-eluting stent implantation

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    Kim, In Soo [Cadiovascular center, Chonnam National University Hospital, Gwangju (Korea, Republic of); Han, Jae Bok; Jang, Seong Joo [Dept. of Radiology, Dongshin University, Naju (Korea, Republic of)

    2014-06-15

    Many studies have suggested that in the era of Drug Eluting Stents (DES) are one of the causes of In-Stent Restenosis (ISR) of Stent Fracture (SF). The present study sought to evaluate clinical characteristics of patients with stent fracture after successful DES implantation. The 4,701 patients were selected for analysis who underwent a follow-up coronary angiography irrespective of ischemic symptoms. The overall incidence of SF was 32 patients(male:female=19:13, Av. age 62.44±9.8 year, 0.68%). Fractures of Sirolimus-Eluting Stents (SES), Paclitaxel-Eluting Stents (PES), Biolimus A9-Eluting Stents (BES), Everolimus-Eluting Etents (EES), Endothelial Progenitor Cell Capture Stent (EPC) and Zotarolimus-Eluting Stents (ZES) are accounted for 19 (59.4%), 9 (28.1%), 2 (6.3%), 1 (3.1%), 1 (3.1%) and 0 (0%) respectively. SF developed in the left Anterior Dscending (LAD) artery in 16 patients (50%) and in complex(type B2, C) lesions in 25 patients (69.4%). Ten patients were treated with heterogenous DES, the rest being treated with either homogenous DES (3 patients), plain old balloon angioplasty (3 patients), or conservative medical treatment (17 patients). None of the patients with SF suffered from cardiac death during a follow-up period of 32.9±12.4 months. The overall rate of DES fracture over up to 3.7 years of follow-up was 0.68% with higher incidence in SES than in PES. SF frequently occurred in the LAD artery and in complex lesions. Of the patients with SF, coronary intervention was performed only when the binary restenosis lesion was significant. During the follow-up, patients with SF have continued on combination antiplatelet therapy. There is a very low rate of major adverse cardiac events(post-detection of SF), especially cardiac death associated with SF.

  3. Outcomes after coronary stent implantation in patients with metal allergy.

    Science.gov (United States)

    Romero-Brufau, Santiago; Best, Patricia J M; Holmes, David R; Mathew, Verghese; Davis, Mark D P; Sandhu, Gurpreet S; Lennon, Ryan J; Rihal, Charanjit S; Gulati, Rajiv

    2012-04-01

    Clinical outcomes after stent placement in patients with a history of metal allergy remain incompletely understood. We performed a single-center retrospective study to evaluate such outcomes. Twenty-nine allergic patients who underwent coronary stent implantation were compared with a nonallergic group (n=250) matched for demographics and a propensity score for allergy to metal. Hypersensitivity to nickel was reported in 26 of 29 and chromium in 9 of 29. Patch testing performed in 11 of 29 patients was positive in all. Comparing allergy versus control subjects, there were no differences in number of segments treated (1.4±0.7 versus 1.5±0.7), stents placed (1.7±1.1 versus 1.6±0.9), and frequency of drug-eluting stent usage (52% versus 60%). In-hospital death (0% versus 0%), myocardial infarction (MI, 4% versus 3%, P=0.27), and 30-day death (3% versus 0%, P=0.53) and MI (3% versus 4%, P=0.71) were statistically similar. There were no differences in 4-year death (12% versus 13%), target lesion revascularization (TLR, 13 versus 17%, P=0.54), or death/MI/TLR (24% versus 34%, P=0.20). Clinically driven repeat angiography in 12 of 29 allergy patients revealed binary restenosis rates of 27% in bare metal stents and 0% in drug-eluting stents, with mean diameter in-stent restenosis of 36% and 8%, respectively. There was no change in circulating eosinophil and lymphocyte counts after stenting in the allergy group (0.19-0.20, P=0.67, and 1.90-1.79, P=0.59, respectively). A history of metal allergy was not associated with adverse early or late outcomes in this single-center study.

  4. 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

  5. Effect of pioglitazone on in-stent restenosis after coronary drug-eluting stent implantation: a meta-analysis of randomized controlled trials.

    Directory of Open Access Journals (Sweden)

    Ming-duo Zhang

    Full Text Available In-stent restenosis (ISR remains a common life-threatening complication and some studies have shown that pioglitazone can reduce the incidence of ISR in patients with drug-eluting stents (DES implantation. We conducted a meta-analysis to assess the effect of pioglitazone in preventing ISR after DES implantation.Randomized controlled trials (RCTs investigating the effects of pioglitazone for ISR after DES implantation were identified by systematic searches of multiple online databases and manual searches of related reference lists of identified trials through May 2014. The primary endpoint was the rate of ISR. Secondary endpoints included minimum lumen diameter, percentage stenosis of stented vessels, late loss, in-stent neointimal volume, target vessel revascularization (TVR, target lesion revascularization, myocardial infarction, stent thrombosis and death.Five studies, comprising 255 pioglitazone-treated patients and 245 controls, were identified in the current meta-analysis. Pioglitazone did not significantly reduce the rate of ISR (P = 0.20 with low heterogeneity (I2 = 13.3%, P = 0.32. For the secondary outcomes, pioglitazone did not substantially affect the pooled estimates of these endpoints except late loss (P = 0.01 and TVR (P = 0.04.The limited evidence indicates that pioglitazone does not demonstrate markedly beneficial effect in patients subjected to coronary DES implantation. However, the results should be interpreted with care given the small sample size. Further large-scale RCTs are needed.

  6. Assessment of a Polyester-Covered Nitinol Stent in the Canine Aorta and Iliac Arteries

    International Nuclear Information System (INIS)

    Castaneda, Flavio; Ball-Kell, Susan M.; Young, Kate; Li Ruizong

    2000-01-01

    Purpose: To evaluate the patency and healing characteristics of a woven polyester fabric-covered stent in the canine model.Methods: Twenty-four self-expanding covered stents were placed in the infrarenal aorta and bilateral common iliac arteries of eight dogs and evaluated at 1 (n = 2), 3 (n = 2), and 6 (n = 4) months. Stent assessment was done using angiography prior to euthanasia, and light and scanning electron microscopy.Results: Angiographically, just prior to euthanasia, 8 of 8 aortic and 14 of 16 iliac endovascular covered stents were patent. Histologically, the stented regions showed complete endothelialization 6 months after graft implantation. A neointima had formed inside the stented vessel regions resulting in complete encasement of the fabric-covered stent by 3 months after graft implantation. Medial compression with smooth muscle cell atrophy was present in all stented regions. Explanted stent wires, examined by scanning electron microscopy, showed pitting but no cracks or breakage.Conclusion: The covered stent demonstrated predictable healing and is effective in preventing stenosis in vessels 10.0 mm or greater in diameter but does not completely preclude stenosis in vessels 6.0 mm or less in diameter

  7. Aspirin desensitization in patients undergoing planned or urgent coronary stent implantation. A single-center experience

    NARCIS (Netherlands)

    Luca, G. De; Verdoia, M.; Binda, G.; Schaffer, A.; Suryapranata, H.; Marino, P.

    2013-01-01

    INTRODUCTION: Dual antiplatelet therapy (aspirin and ADP-antagonists) is mandatory after stent implantation in order to avoid stent thrombosis, especially in the era of DES. In fact, a delayed re-endothelization process may enlarge the window of occurrence of stent thrombosis beyond 1-year after

  8. Coronary stent on coronary CT angiography: Assessment with model-based iterative reconstruction technique

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Eun Chae; Kim, Yeo Koon; Chun, Eun Ju; Choi, Sang IL [Dept. of of Radiology, Seoul National University Bundang Hospital, Seongnam (Korea, Republic of)

    2016-05-15

    To assess the performance of model-based iterative reconstruction (MBIR) technique for evaluation of coronary artery stents on coronary CT angiography (CCTA). Twenty-two patients with coronary stent implantation who underwent CCTA were retrospectively enrolled for comparison of image quality between filtered back projection (FBP), adaptive statistical iterative reconstruction (ASIR) and MBIR. In each data set, image noise was measured as the standard deviation of the measured attenuation units within circular regions of interest in the ascending aorta (AA) and left main coronary artery (LM). To objectively assess the noise and blooming artifacts in coronary stent, we additionally measured the standard deviation of the measured attenuation and intra-luminal stent diameters of total 35 stents with dedicated software. All image noise measured in the AA (all p < 0.001), LM (p < 0.001, p = 0.001) and coronary stent (all p < 0.001) were significantly lower with MBIR in comparison to those with FBP or ASIR. Intraluminal stent diameter was significantly higher with MBIR, as compared with ASIR or FBP (p < 0.001, p = 0.001). MBIR can reduce image noise and blooming artifact from the stent, leading to better in-stent assessment in patients with coronary artery stent.

  9. The effect of sirolimus-eluting stent implantation on re-endothelialization: a comparative study with bare-metal stent implantation in rabbits

    International Nuclear Information System (INIS)

    Zhang Lin; ZZhang Ruiyan; Zhu Zhengbin; Du Run; Shen Weifeng

    2009-01-01

    Objective: To evaluate the effect of sirolimus-eluting stent implantation on the reendothelialization of abdominal aorta in rabbits, and to compare it with that of bare-metal stent implantation. Methods: Twenty-four New Zealand male rabbits were randomly and equally divided into two groups after hyperlipemia feeding. Sirolimus-eluting stent, Firebird, or bare-metal stent, Mustang, was implanted in the abdominal aorta in two groups. Every three experimental rabbits from both groups were sacrificed each time at 3, 7, 14 and 28 days after the procedure, and the specimens of aorta were harvested and processed for observing the vascular endothelia with scanning electron microscopy, and the degree of re-endothelialization was analyzed by computed imaging analysis technique. Results: Three days after the procedure, in both groups neogenetic endothelia could be hardly seen in the treated aorta although inflammatory reaction was rather obvious. At the time of 7, 14 and 28 days after the operation, the covering rate of re-endothelialization in sirolimus-eluting stent group was significantly lower than that in bare-metal stent group (15% ±8% vs 53% ± 9%, 49% ±16% vs 83% ± 4% and 73% ± 3% vs 93% ± 4% respectively, P < 0.05). Conclusion: Compared with bare-metal stent, sirolimus-eluting stent will markedly delay the re-endothelialization of the implanted vessels. (authors)

  10. 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.

  11. Intravascular ultrasound assessment of minimumlumen area and intimal hyperplasia in in-stent restenosis after drug-eluting or bare-metal stent implantation. The Nordic Intravascular Ultrasound Study (NIVUS)

    DEFF Research Database (Denmark)

    Jensen, Lisette Okkels; Vikman, Saila; Antonsen, Lisbeth

    2017-01-01

    Introduction: Drug-eluting stents (DES) reduce the risk of restenosis after percutaneous coronary intervention. The aim of the study was to evaluate, by intravascular ultrasound (IVUS), the minimum lumen area site in the stented segment and the distribution of intimal hyperplasia in patients...

  12. 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.

  13. Optical coherence tomography for the assessment of pericardium covered stents for the treatment of degenerated saphenous vein grafts

    NARCIS (Netherlands)

    P. Tyczynski (Pawel); N. Kukreja (Neville); R.J.M. van Geuns (Robert Jan); J.J. Wykrzykowska (Joanna); M.N. Sheppard (Mary); C. di Mario (Carlo)

    2010-01-01

    textabstractAims: Pre- and post-interventional optical coherence tomography (OCT) assessment of degenerated saphenous vein grafts (SVG) treated with implantation of pericardium covered stents. Percutaneous treatment of SVG represents one of the major challenges of current percutaneous coronary

  14. Influence of Vessel Size and Tortuosity on In-stent Restenosis After Stent Implantation in the Vertebral Artery Ostium

    International Nuclear Information System (INIS)

    Zhou Zhiming; Yin Qin; Xu Gelin; Yue Xuanye; Zhang Renliang; Zhu Wusheng; Fan Xiaobing; Ma Minmin; Liu Xinfeng

    2011-01-01

    Purpose: Percutaneous transluminal angioplasty and stenting is emerging as an alternative for treating atherosclerotic stenosis in the vertebral artery ostium. However, in-stent restenosis (ISR) still remains a critical issue to be addressed. Little is known about the relationship between anatomic characteristics of the artery and ISR after stent implantation. In this study, we have evaluated influential factors for ISR in a cohort of the patients with stenting in the vertebral artery ostium. Methods: Sixty-one patients with 63 symptomatic lesions in vertebral artery ostium treated with stenting were enrolled onto this study. An average of 12.5 months’ clinical and angiographic follow-up results were analyzed retrospectively. The possible influential factors for ISR, including conventional risk factors of cerebrovascular diseases and morphological characteristics of target lesions, were evaluated by univariate and multivariate regression analysis. Results: Technical success was achieved in all 63 interventional procedures. Stenosis was reduced from (mean ± standard deviation) 75.5 ± 12% before to 1 ± 3.6% after the procedure. During the mean 12.5-month angiographic follow-up, ISR was detected in 17 treated vessels (27.0%), with 2 treated arteries (3.2%) resulting in occlusion, and a stent fracture in 1 case (1.6%). Multivariate Cox regression analysis showed that the tortuosity of V1 (hazard ratio 3.54, P = 0.01) and smaller diameter of the stent (hazard ratio 3.8, P = 0.04) were independent predictors of ISR. Conclusions: Angioplasty and stenting for symptomatic stenosis in the vertebral artery ostium stenosis seem to be feasible and effective. Tortuosity and smaller diameter may affect ISR after stent implantation.

  15. Intracranial Stent Implantation for Drug Resistant Atherosclerotic Stenosis: Results of 52 Cases

    International Nuclear Information System (INIS)

    Kim, Kuk Seon; Hwang, Dae Hyun; Ko, Young Hwan; Kang, Ik Won; Lee, Eil Seong; Han, You Mie; Kim, In Soo; Hur, Choon Woong

    2011-01-01

    We evaluated the usefulness of intracranial stent implantation for treatment of drug resistant atherosclerotic stenoses. Between March 2004 and July 2007, we tried intracranial stent implantation in 49 patients with 52 lesions (anterior circulation 48 cases, posterior circulation 4 cases) who had an ischemic stroke with more than 50% of major cerebral artery stenosis. We classified the lesions by their location and morphology, analyzed the results in terms of the success rate, complication rate, and restenosis rate during the follow-up period. Intracranial stent implantation was performed successfully in 43 cases (82.7%). In eight of the nine cases, the stent implantation failure was due to the tortuosity of the target vessel. There was no major periprocedural complication. One patient showed cerebellar infarction after the procedure. Mean residual stenoses decreased from 70.2% to 13.0%. Four cases (9.3%) demonstrated in-stent restenoses and more than 50% during the mean and 25.3/month after the follow-up period. Success rate of intracranial stent implantation may improve on developing technique and more experience. Low rate of complication and restenosis suggest that we can consider intracranial stent implantation for treatment of drug resistant atherosclerotic stenoses.

  16. Treatment of 9 cases of pulmonary atelectasis caused by endobronchial tuberculosis with intraluminal stent implantation

    International Nuclear Information System (INIS)

    Ji Hongjiang; Li Qiang; Liu Zhongling; Bai Chong; Yao Xiaopeng; Zhao Lijun; Xu Hao; Dong Yuchao; Huang Haidong; Wang Qin

    2007-01-01

    Objective: To evaluate the effect and safety of intraluminal stent implantation in the treatment of complete airway obstruction with unilateral pulmonary atelectasis caused by endobronchial tuberculosis (EBTB). Methods: 9 cases of pulmonary atelectasis caused by EBTB were treated with high- frequency electricity/microwave, balloon dilation and endobronchial stent implantation. At the time of 1 week and 4-6 months after stenting ,the diameters of stenotic segment were measured. Results: All 9 cases with atelectasis of EBTB showed complete re-expansion within 3 days after the stent implantation. The mean diameter of the stenotic segments of 9 EBTB patients increased to 9.17 ± 1.24 mm at 7th day after stent implantation; 3 of 9 EBTB patients occured mild restenosis after implantation of tracheobronchial stents. However, combination therapy of cryotherapy and balloon dilation can effectively prevent the aggravation of restenosis. Conclusion: Comparing with traditional surgical treatment, the intraluminal stent implantation for atelectasis caused by EBTB is a new, effective, safe and microtraumatic method with reliable preservation of pulmonary function. (authors)

  17. Implante de ducto nasolacrimal de poliuretano: relato de caso Nasolacrimal stent implantation: report of a case

    Directory of Open Access Journals (Sweden)

    Patrícia Lunardelli

    2008-02-01

    Full Text Available Obstrução parcial ou completa da via lacrimal provoca um lacrimejamento constante ou intermitente denominado epífora. O tratamento preconizado para os casos de epífora com obstruções localizadas abaixo do canalículo comum é a dacriocistorrinostomia externa ou a dacriocistorrinostomia via endoscópica. Nos últimos anos foram criadas e aperfeiçoadas técnicas alternativas para o tratamento de epífora como a intubação da via lacrimal com tubos de silicone, dilatação do ducto nasolacrimal (dacriocistoplastia e o desenvolvimento de implantes nasolacrimais. O objetivo deste trabalho é relatar a primeira experiência brasileira com o implante de poliuretano, realizado pelos serviços de Radiologia Intervencionista e Oftalmologia do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo - USP - SP. Embora o implante nasolacrimal tenha suas vantagens por ser um procedimento radiológico intervencionista versus uma cirurgia invasiva, não é o procedimento indicado como tratamento primário da obstrução do ducto nasolacrimal. Estudos a longo prazo ainda são necessários para avaliar e resolver as complicações encontradas nos últimos trabalhos. Novos desenhos e métodos de recanalização in situ (mecanicamente ou com auxílio de medicações talvez melhorem a viabilidade deste método terapêutico para a resolução de epífora.Epiphora (watering eye is generally caused by insufficient drainage of tears. The most common cause of epiphora in adults is idiopathic inflammatory obstruction of the nasolacrimal duct. The traditional surgical treatment of nasolacrimal duct obstruction is an external dacryocystorhinostomy, which has an 85% to 95% success rate. To eliminate cutaneus wounds and scarring some techniques were introduced, for example the endonasal laser dacryocystorhinostomy and the nasolacrimal stent. The aim of this report was to evaluate the first case of nasolacrimal stent implantation in Brazil. The

  18. Association of moderate chronic kidney disease with insufficient improvement of fractional flow reserve after stent implantation.

    Science.gov (United States)

    Sakoda, Kunihiro; Tanaka, Nobuhiro; Hokama, Yohei; Hoshino, Kou; Murata, Naotaka; Yamashita, Jun; Yamashina, Akira

    2016-08-01

    This study aims to investigate the association of moderate chronic kidney disease (CKD) with fractional flow reserve (FFR) after stent implantation. Patients with moderate CKD have a higher prevalence of severe and diffuse coronary artery disease, and have increased risk of cardiovascular events even after stent implantation. On the other hand, in some patients, FFR could not be sufficiently improved even after stent implantation. However, the association between these pathophysiological processes is unclear. A total of 102 patients with stable angina, in whom a stent was implanted for the left anterior descending coronary artery (LAD) lesion, were included. Patients with a severely decreased glomerular filtration rate (GFR; > CKD stage 4) were excluded. Patients were stratified into 3 groups: those with an estimated GFR (eGFR) ≥ 60 mL per min per 1.73 m(2) (stage 0-2), 45 to 59 mL per min per 1.73 m(2) (stage 3a), and 30 to 44 mL per min per 1.73 m(2) (stage 3b). FFR after stent implantation (post-stent FFR) was significantly lower in the stage 3b group than in both the stage 0-2 group and the stage 3a group (P < 0.01). Post-stent FFR had a significant positive correlation with eGFR (r = 0.223, P = 0.024). Multivariate analysis demonstrated that eGFR was an independent predictor of post-stent FFR. Moderate CKD was independently associated with insufficient improvement of FFR after stent implantation. This can partly explain the poor prognosis of patients with CKD. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.

  19. Sex differences in the outcomes of stent implantation in mini-swine model.

    Science.gov (United States)

    Kunio, Mie; Wong, Gee; Markham, Peter M; Edelman, Elazer R

    2018-01-01

    Sex-related differences have been noted in cardiovascular anatomy, pathophysiology, and treatment responses, yet we continued to drive evaluation of vascular device development in animal models without consideration of animal sex. We aimed to understand sex-related differences in the vascular responses to stent implantation by analyzing the pooled data of endovascular interventions in 164 Yucatan mini-swine (87 female, 77 male). Bare metal stents (BMS) or drug-eluting stents (DES) were implanted in 212 coronary arteries (63 single BMS implantation, 68 single DES implantation, 33 overlapped BMS implantation, and 48 overlapped DES implantation). Histomorphological parameters were evaluated from vascular specimens at 3-365 days after stent implantation and evaluated values were compared between female and male groups. While neointima formation at all times after implantation was invariant to sex, statistically significant differences between female and male groups were observed in injury, inflammation, adventitial fibrosis, and neointimal fibrin deposition. These differences were observed independently, i.e., for different procedure types and at different follow-up timings. Only subtle temporal sex-related differences were observed in extent and timing of resolution of inflammation and fibrin clearance. These subtle sex-related differences may be increasingly important as interventional devices meld novel materials that erode and innovations in drug delivery. Erodible materials may act differently if inflammation has a different temporal sequence with sex, and drug distribution after balloon or stent delivery might be different if the fibrin clearance speaks to different modes of pharmacokinetics in male and female swine.

  20. Metallic stent implantation in the treatment of malignant tracheal stenosis under general anaesthesia

    International Nuclear Information System (INIS)

    Bai Xuming; Jin Yong; Xie Hong; Cheng Long; Gu Xingshi; Chang Liuhui

    2012-01-01

    operation] and increased further after the operation [(94.5 ±4.3)%], t=2.06 and 2.26, P<0.01. Blood pressure (BP) showed no changes throughout the operation (P>0.05). The comprehensive assessment of operation were favorable in all patients. Conclusion: With careful preoperative evaluation and planning, tracheal stent implantation under general anaesthesia in patients with malignant tracheal stenosis is feasible and safe. (authors)

  1. Determinants of slow flow following stent implantation in intravascular ultrasound-guided primary percutaneous coronary intervention.

    Science.gov (United States)

    Watanabe, Yusuke; Sakakura, Kenichi; Taniguchi, Yousuke; Yamamoto, Kei; Wada, Hiroshi; Fujita, Hideo; Momomura, Shin-Ichi

    2018-03-01

    Slow flow is a serious complication in primary percutaneous coronary intervention (PCI) and is associated with poor clinical outcomes. Intravascular ultrasound (IVUS)-guided PCI may improve clinical outcomes after drug-eluting stent implantation. The purpose of this study was to seek the factors of slow flow following stent implantation, including factors related to IVUS-guided primary PCI. The study population consisted of 339 ST-elevation myocardial infarction patients, who underwent stent deployment with IVUS. During PCI, 56 patients (16.5%) had transient or permanent slow flow. Multivariate logistic regression analysis showed age (OR 1.04, 95% CI 1.01-1.07, P = 0.01), low attenuation plaque on IVUS (OR 3.38, 95% CI 1.70-6.72, P = 0.001), initial Thrombolysis In Myocardial Infarction (TIMI) flow grade 2 (vs. TIMI 0: OR 0.44, 95% CI 0.20-0.99, P = 0.046), and the ratio of stent diameter to vessel diameter (per 0.1 increase: OR 2.63, 95% CI 1.84-3.77, P flow. A ratio of stent diameter to vessel diameter of 0.71 had an 80.4% sensitivity and 56.9% specificity to predict slow flow. There was no significant difference in ischemic-driven target vessel revascularization between the modest stent expansion (ratio of stent diameter to vessel diameter flow following stent implantation in IVUS-guided primary PCI.

  2. Emergency and elective implantation of covered stent systems in iatrogenic arterial injuries

    Energy Technology Data Exchange (ETDEWEB)

    Goltz, J.P.; Kickuth, R. [Universitaetsklinikum Wuerzburg (Germany). Inst. fuer Roentgendiagnostik; Bastuerk, P.; Hoppe, H.; Triller, J. [Universitaetsspital Bern (Switzerland). Inst. fuer Diagnostische, Interventionelle und Paediatrische Radiologie

    2011-07-15

    Purpose: To evaluate the effectiveness and safety of covered stents for the management of iatrogenic arterial injury. Materials and Methods: Between 03/1998 and 12/2009, 31 patients underwent selective covered stent implantation after iatrogenic arterial injury. 12/31 of these patients (38.7 %) were hemodynamically unstable. Six different endovascular covered stent types were utilized. The primary endpoints of this study were technical and clinical success and rates of minor and major complications. Results: Initial angiograms demonstrated active extravasation in 19 (61.3 %) patients and pseudoaneurysms in 12 (38.7 %) patients. The following sites of bleeding origin were detected: axillary artery, subclavian artery, common iliac artery, external iliac artery, internal iliac artery, common femoral artery, superficial femoral artery, popliteal and fibular artery, femoro-popliteal and popliteo-crural bypasses, common hepatic artery, aberrant hepatic artery, cystic and gastroduodenal artery. In all patients bleeding was effectively controlled by covered stent implantation resulting in an immediate technical success of 100 %. Clinical success attributed to covered stent implantation was documented in 30 of the 31 patients (96.8 %). Major complications included death in four patients (11.1 %), acute thrombosis with arm ischemia in one patient (2.8 %) and stent fracture with associated pseudoaneurysm in another patient (2.8 %). In 2/31 patients (6.5 %) covered stent failure was detected and successfully treated by implantation of a second covered stent. Conclusion: Emergency and elective implantation of covered stents may be used for minimally invasive and effective management of iatrogenic arterial injury. (orig.)

  3. 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

  4. An assessment on modified AZ80 alloys for prospect biodegradable CV stent applications

    NARCIS (Netherlands)

    Erinc, M.; Sillekens, W.H.

    2009-01-01

    In medicine, stents are inserted into an artery to prevent local constrictions to blood flow. Commonly used stents are permanent metal stents, yet developments in this area are more and more heading towards biodegradable stents. Implants made of materials that can dissolve in the patient's body by

  5. Artery Soft-Tissue Modelling for Stent Implant Training System

    Directory of Open Access Journals (Sweden)

    Giovanni Aloisio

    2004-08-01

    Full Text Available Virtual reality technology can be utilised to provide new systematic training methods for surgical procedures. Our aim is to build a simulator that allows medical students to practice the coronary stent implant procedure and avoids exposing patients to risks. The designed simulation system consists of a virtual environment and a haptic interface, in order to provide both the visualization of the coronary arteries and the tactile and force feedback generated during the interactions of the surgical instruments in the virtual environment. Since the arteries are soft tissues, their shape may change during an operation; for this reason physical modelling of the organs is necessary to render their behaviour under the influence of surgeon's instruments. The idea is to define a model that computes the displacement of the tissue versus time; from the displacement it is possible to calculate the response of the tissue to the surgical tool external stimuli. Information about tools displacements and tissue responses are also used to graphically model the artery wall and virtual surgical instrument deformations generated as a consequence of their coming into contact. In order to obtain a realistic simulation, the Finite Element Method has been used to model the soft tissues of the artery, using linear elasticity to reduce computational time and speed up interaction rates.

  6. Eosinophilic responses to stent implantation and the risk of Kounis hypersensitivity associated coronary syndrome.

    Science.gov (United States)

    Kounis, Nicholas G; Giannopoulos, Sotiris; Tsigkas, Grigorios G; Goudevenos, John

    2012-04-19

    The use of drug eluting stents constitutes a major breakthrough in current interventional cardiology because it is more than halves the need of repeat interventions. It is incontrovertible that coronary stents, in general, have been beneficial for the vast majority of patients. A small increase in thrombosis, following DES implantation, is offset by a diminished risk of complications associated with repeat vascularization. However, late and, especially, very late stent thrombosis is a much feared complication because it is associated with myocardial infarction with increased mortality. Despite that stent thrombosis is thought to be multifactorial, so far clinical reports and reported pathology findings in patients died from coronary stent thrombosis as well as animal studies and experiments, point toward a hypersensitivity inflammation. The stented and thrombotic areas are infiltrated by interacting, via bidirectional stimuli inflammatory cells including eosinophils, macrophages, T-cells and mast cells. Stented regions constitute an ideal surrounding for endothelial damage and dysfunction, together with hemorheologic changes and turbulence as well as platelet dysfunction, coagulation and fibrinolytic disturbances. Drug eluting stent components include the metal strut which contains nickel, chromium, manganese, titanium, molybdenum, the polymer coating and the impregnated drugs which for the first generation stents are: the antimicrotubule antineoplastic agent paclitaxel and the anti-inflammatory, immunosuppressive and antiproliferative agent sirolimus. The newer stents which are called cobalt-chromiun stents and elute the sirolimus analogs everolimus and zotarolimus both contain nickel and other metals. All these components constitute an antigenic complex inside the coronary arteries which apply chronic, continuous, repetitive and persistent inflammatory action capable to induced Kounis syndrome and stent thrombosis. Allergic inflammation goes through three phases

  7. 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

  8. A simple three-dimensional stent for proper placement of mini-implant.

    Science.gov (United States)

    Felicita, A Sumathi

    2013-11-12

    This paper deals with the fabrication of a three-dimensional stent which is simple in design but provides an accurate placement of a mini-implant in three planes of space, namely, sagittal (root proximity), vertical (attached gingiva/alveolar mucosa) and transverse (angulation). The stent is made of 0.018×0.025 in. stainless steel archwire which consists of a 'u loop' angulated at 20°, a vertical limb, a horizontal limb and a stop. The angulation of the 'u' helps in the placement of the mini-implant at 70° to the long axis of the tooth. The vertical height is determined such that the mini-implant is placed at the mucogingival junction. The mini-implant is placed with the aid of the stent, and its angulation and proximity to the adjacent roots are checked with a cone beam computed tomography image. The cone beam computed tomography image showed the mini-implant at an angle of 70° to the long axis of the tooth. There is no contact between mini-implant and the roots of the adjacent teeth. This stent is simple, easy to fabricate, cost-effective, and provides ease of insertion/removal, and three-dimensional orientation of the mini-implant.

  9. Stent implantation of left main coronary artery stenosis in an infant: Effective long-term treatment?

    Directory of Open Access Journals (Sweden)

    Christian Paech

    2015-01-01

    Full Text Available Coronary artery stenosis is a rare phenomenon in children. Coronary stent implantation is generally not considered a standard treatment option due to technical difficulties and potential complications in this group of patients. Nevertheless, several pediatric cases reporting successful implantation with acceptable short-term experiences have been described. The following case presents a successful stent implantation for left main coronary artery (LMCA stenosis early after surgery for anomalous left coronary artery from pulmonary artery (ALCAPA at the age of 6 months. The excellent mid-term results and notably the procedure′s potential as a long-term treatment in small children are highlighted. A 6-month-old infant underwent surgery for ALCAPA. Due to sudden postoperative deterioration, cardiac catheterization was performed. Coronary angiography revealed severe (90% ostial LMCA stenosis. A PROMUS drug-eluting stent (Promus Element AL3.0 Χ 8 mm, Boston Scientific, Natick, Massachusetts, USA was implanted. The procedure was performed without complications. Antiplatelet therapy with acetylsalicylic acid and clopidogrel was initiated. Subsequently, cardiac function improved slowly. Cardiac catheterization 3 years 8 months after stent implantation showed no restenosis with a proximal LMCA diameter still at the 50 th percentile for age. Neither were signs of heart failure reported at the last follow-up at 7 years of age. Presupposing normal growth, the implanted stent would thus provide sufficient myocardial perfusion with a LMCA lumen at the 40 th percentile at the age of 16 years. In selected cases, coronary stent implantation may be an effective mid- to long-term treatment of coronary artery stenosis even in very young children.

  10. Mechanisms of Very Late Drug-Eluting Stent Thrombosis Assessed by Optical Coherence Tomography

    DEFF Research Database (Denmark)

    Taniwaki, Masanori; Radu, Maria D; Zaugg, Serge

    2016-01-01

    BACKGROUND: The pathomechanisms underlying very late stent thrombosis (VLST) after implantation of drug-eluting stents (DES) are incompletely understood. Using optical coherence tomography, we investigated potential causes of this adverse event. METHODS AND RESULTS: Between August 2010 and Decemb...

  11. Correção endovascular da aorta ascendente associada a implante de stents coronários

    OpenAIRE

    Saadi, Eduardo Keller; Moura, Leandro de; Zago, Alexandre do Canto; Zago, Alcides José

    2011-01-01

    Endovascular treatment of ascending aorta pseudoanerysms with coronary stents implantation at the same procedure was feasable, although longer followup is necessary.Tratamento endovascular de pseudoaneurismas da aorta ascendente com o implante de stents coronários no mesmo procedimento foi factível, embora seja necessário um maior seguimento.

  12. 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 ...

  13. Anastomotic leak after oesophagectomy and stent implantation: a systematic review

    Directory of Open Access Journals (Sweden)

    A.N. Kanatas

    2011-12-01

    Full Text Available Anastomotic leaks following oesophageal cancer resection have a high mortality. Stents have an established position in the palliation of dysphagia due to malignancy and in treating malignant perforation or fistula. They are increasingly used for benign conditions such as spontaneous oesophageal perforation with encouraging results. In this systematic review we examine the available evidence and attempt to define the role of stents in the management of oesophageal anastomotic leaks after resection for cancer. It is evident from the review that plastic- and metal-covered stents are an effective strategy for the treatment of anastomotic leaks. Vigilance is required as complications such as stent migration and incomplete sealing are not uncommon. Further clinical studies with greater methodological rigor in terms of sample size and study design may confirm that stents have an important contribution to make in the management of oesophageal anastomotic leak.

  14. Development and Assessment of a 3D-Printed Scaffold with rhBMP-2 for an Implant Surgical Guide Stent and Bone Graft Material: A Pilot Animal Study

    Directory of Open Access Journals (Sweden)

    Ji Cheol Bae

    2017-12-01

    Full Text Available In this study, a new concept of a 3D-printed scaffold was introduced for the accurate placement of an implant and the application of a recombinant human bone morphogenetic protein-2 (rhBMP-2-loaded bone graft. This preliminary study was conducted using two adult beagles to evaluate the 3D-printed polycaprolactone (PCL/β-tricalcium phosphate (β-TCP/bone decellularized extracellular matrix (bdECM scaffold conjugated with rhBMP-2 for the simultaneous use as an implant surgical guide stent and bone graft material that promotes new bone growth. Teeth were extracted from the mandible of the beagle model and scanned by computed tomography (CT to fabricate a customized scaffold that would fit the bone defect. After positioning the implant guide scaffold, the implant was placed and rhBMP-2 was injected into the scaffold of the experimental group. The two beagles were sacrificed after three months. The specimen block was obtained and scanned by micro-CT. Histological analysis showed that the control and experimental groups had similar new bone volume (NBV, % but the experimental group with BMP exhibited a significantly higher bone-to-implant contact ratio (BIC, %. Within the limitations of this preliminary study, a 3D-printed scaffold conjugated with rhBMP-2 can be used simultaneously as an implant surgical guide and a bone graft in a large bone defect site. Further large-scale studies will be needed to confirm these results.

  15. Development and Assessment of a 3D-Printed Scaffold with rhBMP-2 for an Implant Surgical Guide Stent and Bone Graft Material: A Pilot Animal Study

    Science.gov (United States)

    Bae, Ji Cheol; Lee, Jin-Ju; Shim, Jin-Hyung; Park, Keun-Ho; Lee, Jeong-Seok; Bae, Eun-Bin; Choi, Jae-Won; Huh, Jung-Bo

    2017-01-01

    In this study, a new concept of a 3D-printed scaffold was introduced for the accurate placement of an implant and the application of a recombinant human bone morphogenetic protein-2 (rhBMP-2)-loaded bone graft. This preliminary study was conducted using two adult beagles to evaluate the 3D-printed polycaprolactone (PCL)/β-tricalcium phosphate (β-TCP)/bone decellularized extracellular matrix (bdECM) scaffold conjugated with rhBMP-2 for the simultaneous use as an implant surgical guide stent and bone graft material that promotes new bone growth. Teeth were extracted from the mandible of the beagle model and scanned by computed tomography (CT) to fabricate a customized scaffold that would fit the bone defect. After positioning the implant guide scaffold, the implant was placed and rhBMP-2 was injected into the scaffold of the experimental group. The two beagles were sacrificed after three months. The specimen block was obtained and scanned by micro-CT. Histological analysis showed that the control and experimental groups had similar new bone volume (NBV, %) but the experimental group with BMP exhibited a significantly higher bone-to-implant contact ratio (BIC, %). Within the limitations of this preliminary study, a 3D-printed scaffold conjugated with rhBMP-2 can be used simultaneously as an implant surgical guide and a bone graft in a large bone defect site. Further large-scale studies will be needed to confirm these results. PMID:29258172

  16. Stent Thrombosis is the Primary Cause of ST-Segment Elevation Myocardial Infarction following Coronary Stent Implantation: A Five Year Follow-Up of the SORT OUT II Study

    DEFF Research Database (Denmark)

    Kristensen, S. L.; Galloe, A. M.; Thuesen, L.

    2014-01-01

    . Notably, definite stent thrombosis was more frequent in female than male STEMI patients (81.8% vs. 56.8%, p=0.09), and in very late STEMIs (p=0.06). Female sex (OR 3.53 [1.01-12.59]) and clopidogrel (OR 4.43 [1.03-19.01]) was associated with increased for definite stent thrombosis, whereas age, time since...... 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...

  17. Assessment of Vascular Stent Heating with Repetitive Transcranial Magnetic Stimulation.

    Science.gov (United States)

    Varnerin, Nicole; Mirando, David; Potter-Baker, Kelsey A; Cardenas, Jesus; Cunningham, David A; Sankarasubramanian, Vishwanath; Beall, Erik; Plow, Ela B

    2017-05-01

    A high proportion of patients with stroke do not qualify for repetitive transcranial magnetic stimulation (rTMS) clinical studies due to the presence of metallic stents. The ultimate concern is that any metal could become heated due to eddy currents. However, to date, no clinical safety data are available regarding the risk of metallic stents heating with rTMS. We tested the safety of common rTMS protocols (1 Hz and 10 Hz) with stents used commonly in stroke, nitinol and elgiloy. In our method, stents were tested in gelled saline at 2 different locations: at the center and at the lobe of the coil. In addition, at each location, stent heating was evaluated in 3 different orientations: parallel to the long axis of coil, parallel to the short axis of the coil, and perpendicular to the plane of the coil. We found that stents did not heat to more than 1°C with either 1 Hz rTMS or 10 Hz rTMS in any configuration or orientation. Heating in general was greater at the lobe when the stent was oriented perpendicularly. Our study represents a new method for ex vivo quantification of stent heating. We have found that heating of stents was well below the Food and Drug Administration standards of 2°C. Thus, our study paves the way for in vivo testing of rTMS (≤10 Hz) in the presence of implanted magnetic resonance imaging-compatible stents in animal studies. When planning human safety studies though, geometry, orientation, and location relative to the coil would be important to consider as well. Copyright © 2017 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  18. Clinical application of transvenous temporary cardiac pacemaker in performing extra-cranial carotid angiography and stent implantation

    International Nuclear Information System (INIS)

    Liu Juan; Yao Guoen; Zhou Huadong; Jiang Xiaojiang; Chen Qiao

    2012-01-01

    Objective: To assess the safety and effectiveness of transvenous temporary cardiac pacemaker in preventing hemodynamic instability occurred during the perioperative period of extra-cranial carotid angiography and stent implantation. Methods: Preoperative install of temporary cardiac pacemaker via left femoral vein was carried out in 41 patients who were at high risk for developing hemodynamic instability, which was followed by extra-cranial carotid angiography and stent implantation. The pacing rhythm of the pacemaker was fixed at 60 beats/min. During and after the procedure the patients were under close observation for the signs of discomfort symptoms as well as the changes in blood pressure and heart rate. The working condition of the pacemaker was also monitored. Results: All the installed pacemakers were technically and hemodynamically effective in producing electrical ventricular responses in all 25 patients who had received balloon dilatation of carotid in advance. Transient pacemaker activation appeared in 25 patients. The longest activation time was one day. During pacemaker activation, one patient developed symptomatic hypotension. The longest duration of hypotension lasted for 4 days. No pacemaker-related or procedure-related complications occurred. Conclusion: Hemodynamic instability is a common complication occurred during perioperative period of extra-cranial carotid angiography and stent implantation. As a prophylactic measure, preoperative placement of temporary cardiac pacemaker can promptly and effectively correct the hemodynamic disorders and prevent perioperative complications such as stroke, etc. Therefore, this technique is worth employing in clinical practice, and it is especially useful for patients with high risks. (authors)

  19. 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.

  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. Should duration of dual antiplatelet therapy depend on the type and/or potency of implanted stent? A pre-specified analysis from the PROlonging Dual antiplatelet treatment after Grading stent-induced Intimal hyperplasia studY (PRODIGY).

    Science.gov (United States)

    Valgimigli, Marco; Borghesi, Marco; Tebaldi, Matteo; Vranckx, Pascal; Parrinello, Giovanni; Ferrari, Roberto

    2013-03-01

    The purpose of this pre-specified analysis of the PROlonging Dual antiplatelet treatment after Grading stent-induced Intimal hyperplasia studY (PRODIGY) was to assess device-specific outcomes relative to different duration of dual antiplatelet therapy (DAPT) after Everolimus- (EES), Paclitaxel (PES), Zotarolimus- (ZES-S) eluting, or bare metal stents (BMS). We randomized 2013 patients to BMS, ZES-S, PES, or EES implantation. At 30 days, each stent group underwent up to 6 or 24 months clopidogrel therapy. The primary endpoint, which was a composite of death, myocardial infarction, or cerebrovascular accident, did not differ in patients receiving BMS [HR: 0.89 (95% CI: 0.54-1.45)], PES [HR: 0.74 (95% CI: 0.43-1.25)], or EES [HR: 0.63 (95% CI: 0.33-1.21)] implantation across DAPT groups, whereas it was significantly higher in ZES-S patients undergoing long when compared with short-term DAPT therapy (HR: 2.85, P = 0.0018), with positive interaction testing (P-value = 0.004). At the 6-month landmark analysis, heterogeneity across stent types persisted for the primary study endpoint and other secondary clinical outcomes, whereas patients receiving PES showed a significantly higher rate of definite, probable and definite, probable, possible stent thrombosis in the short DAPT regimen. No association in absolute or relative terms was noted between stent potency in inhibiting intimal hyperplasia and greater vulnerability to shorter DAPT therapy. Our study suggests that optimal duration of DAPT may be stent-specific and it does not support a clear association between stent potency and vulnerability to shorter DAPT therapy. Trial Registration clinicaltrials.gov Identifier: NCT00611286. http://clinicaltrials.gov/ct2/show/NCT00611286?term=prodigy&rank=2.

  2. Physical Simulation of the Random Failure of Implanted Braided NiTi Stents

    Science.gov (United States)

    Hirmanová, Klára; Pilch, Jan; Racek, Jan; Heller, Luděk; Šittner, Petr; Recman, Lukáš; Petrenec, Martin; Sedlák, Petr

    2014-07-01

    A problem of random clinical failures of the braided esophageal NiTi stents has been addressed by performing physical simulation experiments on helical NiTi springs loaded in cyclic tension in air, water, and simulated biological fluid. Strains and stresses involved in spring deformation were analyzed through simulation by FEM implemented SMA model. It was found that the fatigue life of NiTi springs is significantly lower in fluids than in the air pointing toward the corrosion fatigue mechanism. There is, however, a fatigue limit roughly corresponding to the onset of martensitic transformation in the wire, which is not common for corrosion fatigue. It is proposed that surface TiO2 oxide cracking plays major role in that. Once the oxide layer on the NiTi wire surface fractures, typically during the first mechanical cycle, cracks in the oxide layer periodically open and close during subsequent mechanical cycling. This leads to the localization of mechanical and corrosion attacks under the oxide cracked regions. Microcracks within the surface oxide layer crossing over into the NiTi matrix were indeed revealed by scanning electron microscopy of FIB sections of fatigued wires. A corrosion assisted mechanism for fatigue crack nucleation at the interface between the surface oxide and NiTi matrix is proposed based on the available evidence. The approach opens a space for a better assessment of the corrosion fatigue performance of superelastic NiTi and ultimately for estimation of the lifetime of implanted braided NiTi stents.

  3. Optical coherence tomography for the assessment of pericardium covered stents for the treatment of degenerated saphenous vein grafts.

    Science.gov (United States)

    Tyczynski, Pawel; Kukreja, Neville; van Geuns, Robert-Jan; Wykrzykowska, Joanna J; Sheppard, Mary N; Di Mario, Carlo

    2010-05-01

    Pre- and post-interventional optical coherence tomography (OCT) assessment of degenerated saphenous vein grafts (SVG) treated with implantation of pericardium covered stents. Percutaneous treatment of SVG represents one of the major challenges of current percutaneous coronary interventions (PCI). Artificial membrane-covered stents have failed to show additional benefit over conventional stents. Six cases of PCI of de novo lesions in degenerated SVGs were successfully treated with a novel pericardium covered stent (PCS). Successful deployment was achieved in all cases. Large emboli were retrieved in a distal filter in one case with a long degenerated lesion. Pre- and postinterventional OCT was performed to assess the lesion characteristics and vessel diameter before stenting and the pericardium layer integrity, strut apposition and presence of plaque prolapse after stenting. In order to better understand the OCT images, three PCS of different diameters were deployed in silicone tubes of 700 microm thickness wall with inner tube diameter matching the stent diameter. OCT was repeated after spreading a thin layer of gel inside the tube, mimicking the toothpaste-like plaque observed in SVG. In vivo and in vitro OCT images excluded the presence of plaque prolapse in all but one case and detected a characteristic pattern with bulging of the pericardium between struts, possibly due to trapping of soft intraluminal plaque (or gel) behind the pericardial layer. These cases offer insight into the mechanism of protection against distal embolisation, elucidated by the appearance of these stents after deployment in vivo and in vitro.

  4. Intravascular ultrasound-guided stenting of left main stem dissection after medtronic corevalve implantation

    NARCIS (Netherlands)

    N.M. van Mieghem (Nicolas); P.P.T. de Jaegere (Peter)

    2013-01-01

    textabstractTranscatheter aortic valve implantation (TAVI) implies the introduction, positioning, and deployment of a stented bioprosthesis in the (calcified) native aortic valve. We report an at first glance uneventful TAVI with the Medtronic Corevalve System, which was followed by transient

  5. Comparison of Vascular Responses Following New-Generation Biodegradable and Durable Polymer-Based Drug-Eluting Stent Implantation in an Atherosclerotic Rabbit Iliac Artery Model.

    Science.gov (United States)

    Nakazawa, Gaku; Torii, Sho; Ijichi, Takeshi; Nagamatsu, Hirofumi; Ohno, Yohei; Kurata, Fumi; Yoshikawa, Ayako; Nakano, Masataka; Shinozaki, Norihiko; Yoshimachi, Fuminobu; Ikari, Yuji

    2016-10-19

    Incomplete endothelialization is the primary substrate of late stent thrombosis; however, recent reports have revealed that abnormal vascular responses are also responsible for the occurrence of late stent failure. The aim of the current study was to assess vascular response following deployment of biodegradable polymer-based Synergy (Boston Scientific) and Nobori (Terumo) drug-eluting stents and the durable polymer-based Resolute Integrity stent (Medtronic) in an atherosclerotic rabbit iliac artery model. A total of 24 rabbits were fed an atherogenic diet, and then a balloon injury was used to induce atheroma formation. Synergy, Nobori, and Resolute Integrity stents were randomly implanted in iliac arteries. Animals were euthanized at 28 days for scanning electron microscopic evaluation and at 90 days for histological analysis. The percentage of uncovered strut area at 28 days was lowest with Synergy, followed by Resolute Integrity, and was significantly higher with Nobori stents (Synergy 1.1±2.2%, Resolute Integrity 2.0±3.9%, Nobori 4.6±3.0%; Pfastest stent strut neointimal coverage and the lowest incidence of neoatherosclerosis in the current animal model. © 2016 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

  6. Deferred versus conventional stent implantation in patients with ST-segment elevation myocardial infarction (DANAMI 3-DEFER)

    DEFF Research Database (Denmark)

    Kelbæk, Henning; Høfsten, Dan Eik; Køber, Lars

    2016-01-01

    BACKGROUND: Despite successful treatment of the culprit artery lesion by primary percutaneous coronary intervention (PCI) with stent implantation, thrombotic embolisation occurs in some cases, which impairs the prognosis of patients with ST-segment elevation myocardial infarction (STEMI). We aimed...... stent implantation or deferred stent implantation 48 h after the index procedure if a stabilised flow could be obtained in the infarct-related artery. The primary endpoint was a composite of all-cause mortality, hospital admission for heart failure, recurrent infarction, and any unplanned...... implantation group, with no significant differences between groups. INTERPRETATION: In patients with STEMI, routine deferred stent implantation did not reduce the occurrence of death, heart failure, myocardial infarction, or repeat revascularisation compared with conventional PCI. Results from ongoing...

  7. Natural history of optical coherence tomography-detected non-flow-limiting edge dissections following drug-eluting stent implantation

    DEFF Research Database (Denmark)

    Radu, Maria D; Räber, Lorenz; Heo, Jungho

    2014-01-01

    history and clinical implications remain unclear. The objectives of the present study were to assess the morphology, healing response, and clinical outcomes of OCT-detected edge dissections using serial OCT imaging at baseline and at one year following drug-eluting stent (DES) implantation. METHODS......, and clinical outcomes were assessed. Sixty-three lesions (57 patients) were studied with OCT at baseline and one-year follow-up. Twenty-two non-flow-limiting edge dissections in 21 lesions (20 patients) were identified by OCT; only two (9%) were angiographically visible. Flaps were found in 96% of cases...

  8. A 2D panoramic surgical stent imaging: Complete arch mandibular implant fixed prosthesis along with bar supported maxillary over denture

    Directory of Open Access Journals (Sweden)

    Mukesh Kumar Singhal

    2017-01-01

    Full Text Available Successful rehabilitation of a patient should restore function, esthetic, and speech by prosthesis. Treatment modalities vary from patient to patient. Semi-precision attachments and implants offer several advantages over the traditional approach. The aim and objective of this report was to assess a case of a 55-year-old female patient who had lost all her teeth, except maxillary canines #13 and #23 and with severe bone loss in the mandible. Tooth-supported bar attachment was planned for maxilla, and a total of five dental implants were placed in the mandible using a flapless approach aided by radiographic gutta-percha surgical stents over panoramic two-dimensional imaging. Customized, radiographic stents help for the placement of implant in the view of paralleling and flapless surgery, completely. An immediate loading protocol is adopted as from day of the surgery to 6 weeks along with implant supported full arch fixed dentures after 4 months. The outcome of the treatment was impressive, and the patient gave a positive response with superb esthetics and functions.

  9. A 2D Panoramic Surgical Stent Imaging: Complete Arch Mandibular Implant Fixed Prosthesis along with Bar Supported Maxillary over Denture

    Science.gov (United States)

    Singhal, Mukesh Kumar; Billing, Rumneet Kaur; Srivastava, Nitin; Khan, Zainab

    2017-01-01

    Successful rehabilitation of a patient should restore function, esthetic, and speech by prosthesis. Treatment modalities vary from patient to patient. Semi-precision attachments and implants offer several advantages over the traditional approach. The aim and objective of this report was to assess a case of a 55-year-old female patient who had lost all her teeth, except maxillary canines #13 and #23 and with severe bone loss in the mandible. Tooth-supported bar attachment was planned for maxilla, and a total of five dental implants were placed in the mandible using a flapless approach aided by radiographic gutta-percha surgical stents over panoramic two-dimensional imaging. Customized, radiographic stents help for the placement of implant in the view of paralleling and flapless surgery, completely. An immediate loading protocol is adopted as from day of the surgery to 6 weeks along with implant supported full arch fixed dentures after 4 months. The outcome of the treatment was impressive, and the patient gave a positive response with superb esthetics and functions. PMID:28839424

  10. Th1, Th17, CXCL16 and homocysteine elevated after intracranial and cervical stent implantation.

    Science.gov (United States)

    Tang, Yanyan; Wei, Yunfei; Ye, Ziming; Qin, Chao

    2017-08-01

    The presence of Th1 and Th17 cells has been observed as major inducers in inflammation and immune responses associated stenting. However, there is rare data on the impact of Th1, Th17, CXCL16 and homocysteine after cerebral stent implantation. Here, we performed the statistical analysis to first evaluate the variation of the Th17and Th1 cells and their related cytokines, CXCL16 and homocysteine in the peripheral blood of patients with cerebral stenting. The flow cytometry was used to detect the proportion of Th1 and Th17 cells in peripheral blood mononuclear cells (PBMCs). The enzyme-linked immunosorbent assay was used to measure the serum concentrations of IFN-γ, IL-17 and CXCL16. Plasma homocysteine was examined by immunoturbidimetry. The level of Th1, CXCL16 and homocysteine showed an increase at 3 d, followed by the continuous decrease at 7 d and 3 months. The frequency of Th17 cells increased to a peak at three days, and subsequently decreased with a higher level than baseline. Our data revealed that the variation in Th1, Th17, CXCL16 and homocysteine in peripheral blood of patients with stenting may be implicated in inflammation after intracranial and cervical stent implantation. A better understanding of these factors will provide help for further drug design and clinical therapy.

  11. Late Pseudocoarctation Syndrome After Stent-Graft Implantation For Traumatic Aortic Rupture

    International Nuclear Information System (INIS)

    Letocart, Vincent; Fau, Georges; Tirouvanziam, Ashok; Toquet, Claire; Al Habash, Oussama; Guerin, Patrice; Rousseau, Hervé; Crochet, Dominique

    2013-01-01

    The present observation illustrates an unusual complication occurring after stent-grafting (S-graft) for aortic isthmus rupture. A 22-year-old patient, treated by S-graft in the emergency department for traumatic aortic rupture, was readmitted 10 months later with pseudocoarctation syndrome. A membrane was found inside the stent-graft that had induced a pseudo-dissection, which caused the pseudocoarctation syndrome. Surgical treatment consisted of removing the stent-graft and membrane and replacing it with a vascular implant. The patient’s clinical course was fair. The suggested mechanism was circumferential neoendothelialization of the stent-graft. Dehiscence caused the superior part of the membrane to drop into the lumen of the stent-graft creating a “false channel” that compressed the “true lumen” and induced “pseudocoarctation” syndrome. The cause of the extensive neointimalization remains unexplained. Thoracic aortic stent-grafts require regular follow-up monitoring by angioscan or angio-magnetic resonance imaging.

  12. Late Pseudocoarctation Syndrome After Stent-Graft Implantation For Traumatic Aortic Rupture

    Energy Technology Data Exchange (ETDEWEB)

    Letocart, Vincent, E-mail: vincent.letocart@chu-nantes.fr; Fau, Georges, E-mail: georges.fau@chu-nantes.fr; Tirouvanziam, Ashok, E-mail: ashok.tirouvanziam@chu-nantes.fr [University Hospital of Nantes, Institut du Thorax (France); Toquet, Claire, E-mail: claire.toquet@chu-nantes.fr [University Hospital of Nantes, Department of Pathology (France); Al Habash, Oussama, E-mail: oussama.alhabash@chu-nantes.fr; Guerin, Patrice, E-mail: patrice.guerin@chu-nantes.fr [University Hospital of Nantes, Institut du Thorax (France); Rousseau, Herve, E-mail: rousseau.h@chu-toulouse.fr [University Hospital of Toulouse, Department of Radiology (France); Crochet, Dominique, E-mail: dominique.crochet@chu-nantes.fr [University Hospital of Nantes, Institut du Thorax (France)

    2013-06-15

    The present observation illustrates an unusual complication occurring after stent-grafting (S-graft) for aortic isthmus rupture. A 22-year-old patient, treated by S-graft in the emergency department for traumatic aortic rupture, was readmitted 10 months later with pseudocoarctation syndrome. A membrane was found inside the stent-graft that had induced a pseudo-dissection, which caused the pseudocoarctation syndrome. Surgical treatment consisted of removing the stent-graft and membrane and replacing it with a vascular implant. The patient's clinical course was fair. The suggested mechanism was circumferential neoendothelialization of the stent-graft. Dehiscence caused the superior part of the membrane to drop into the lumen of the stent-graft creating a 'false channel' that compressed the 'true lumen' and induced 'pseudocoarctation' syndrome. The cause of the extensive neointimalization remains unexplained. Thoracic aortic stent-grafts require regular follow-up monitoring by angioscan or angio-magnetic resonance imaging.

  13. The interaction between stent(s) implantation, PICA involvement, and immediate occlusion degree affect symptomatic intracranial spontaneous vertebral artery dissection aneurysm (sis-VADA) recurrence after reconstructive treatment with stent(s)-assisted coiling.

    Science.gov (United States)

    Zhao, Kai-Jun; Zhao, Rui; Huang, Qing-Hai; Xu, Yi; Hong, Bo; Fang, Yi-Bin; Li, Qiang; Yang, Peng-Fei; Liu, Jian-Min; Zhao, Wen-Yuan

    2014-09-01

    We aimed to evaluate risk factors of sis-VADAs recurrence after reconstructive treatment based on 113 reconstructed lesions. A total of 111 patients (M:F = 68:43; median age, 47 years) with 113 sis-VADAs underwent reconstruction from October 2000 to March 2011, using stent(s) and coils. Treatments and predictors of recurrence were retrospectively analysed. Fifty-eight sis-VADAs underwent single-stent treatment, and the remaining 55 sis-VADAs underwent treatment with 2-4 overlapping stents. Follow-up angiography was available for 94 sis-VADAs 12 -78 months, with recurrence in ten patients, including seven angiographic recurrences and three post-treatment haemorrhagic recurrences. A higher rate of post-treatment recurrence was observed in the single stent group than in the multiple stents group (p = 0.010). The interaction between stent (s) implantation and immediate occlusion degree (odds ratio [OR] =3.152; 95% confidence interval [CI], 1.293-7.686; p = 0.012), between stent (s) implantation and the posterior inferior cerebellar artery (PICA) involvement (OR = 4.607; 95% CI, 1.172-18.113; p = 0.029), and between PICA involvement and immediate occlusion degree (OR = 5.018; 95% CI, 1.263-19.933; p = 0.022) affect recurrence in the reconstructed sis-VADAs. This single centre cohort study indicated that the interaction effect between stent (s) implantation, PICA involvement, and immediate occlusion degree were closely associated with recurrence after reconstructive treatment of sis-VADA. The interaction between stent (s) and immediate occlusion degree affect aneurysmal recurrence. The interaction between stent and PICA involvement affect aneurysmal recurrence. The interaction between PICA involvement and immediate occlusion degree affect aneurysmal recurrence.

  14. Stent implantation for the treatment of wide-necked aneurysms located at internal carotid artery bifurcation

    International Nuclear Information System (INIS)

    Xing Ming; Yang Pengfei; Huang Qinghai; Zhao Wenyuan; Hong Bo; Xu Yi; Liu Jianmin

    2012-01-01

    Objective: To preliminarily evaluate the feasibility, safety and efficacy of stent placement for the treatment of wide-necked aneurysms located at internal carotid artery bifurcation. Methods: Eleven patients with wide-necked aneurysms located at internal carotid artery bifurcation, who were encountered during the period from Jan. 2004 to Dec. 2010 in hospital, were collected. A total of 16 intracranial aneurysms were detected, of which 11 were wide-necked and were located at internal carotid artery bifurcation. The diameters of the aneurysms ranged from 2.5 mm to 18 mm. Individual stent type and stenting technique was employed for each patient. Follow-up at 1, 3, 6 and 12 months after the procedure was conducted. Results: A total of 11 different stents were successfully deployed in the eleven patients. The stents included balloon expandable stent (n=1) and self-expanding stent (n=10). According to Raymond grading for the immediate occlusion of the aneurysm, grade Ⅰ (complete obliteration) was obtained in 4, grade Ⅱ (residual neck) in 2 and grade Ⅲ (residual aneurysm) in 5 cases. No procedure-related complications occurred. At the time of discharge, the modified Rankin score was 0-1 in the eleven patients. During the follow-up period lasting for 1-108 months, all the patients were in stable condition and no newly-developed neurological dysfunction or bleeding observed. Follow-up examination with angiography (1-48 months) showed that the aneurysms were cured (no visualization) in 4 cases, improved in 2 cases and in stable condition in one case. Conclusion: For the treatment of wide-necked aneurysms located at internal carotid artery bifurcation, stent implantation is clinically feasible, safe and effective. Further studies are required to evaluate its long-term efficacy. (authors)

  15. A simple three-dimensional stent for proper placement of mini-implant

    OpenAIRE

    Felicita, A Sumathi

    2013-01-01

    Background This paper deals with the fabrication of a three-dimensional stent which is simple in design but provides an accurate placement of a mini-implant in three planes of space, namely, sagittal (root proximity), vertical (attached gingiva/alveolar mucosa) and transverse (angulation). Findings The stent is made of 0.018 × 0.025 in. stainless steel archwire which consists of a ‘u loop’ angulated at 20°, a vertical limb, a horizontal limb and a stop. The angulation of the ‘u’ helps in the ...

  16. Long-term outcome after drug-eluting versus bare-metal stent implantation in patients with ST-segment elevation myocardial infarction

    DEFF Research Database (Denmark)

    Holmvang, Lene; Kelbæk, Henning; Kaltoft, Anne Kjer

    2013-01-01

    This study sought to compare the long-term effects of drug-eluting stent (DES) compared with bare-metal stent (BMS) implantation in patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention.......This study sought to compare the long-term effects of drug-eluting stent (DES) compared with bare-metal stent (BMS) implantation in patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention....

  17. Neointimal hyperplasia after sirolimus-eluting and paclitaxel-eluting stent implantation in diabetic patients: the Randomized Diabetes and Drug-Eluting Stent (DiabeDES) Intravascular Ultrasound Trial

    DEFF Research Database (Denmark)

    Jensen, Lisette Okkels; Maeng, Michael; Thayssen, Per

    2008-01-01

    AIMS: Patients with diabetes have increased risk of in-stent restenosis after coronary stent implantation owing to neointimal hyperplasia (NIH). The aim of the study was to evaluate the extent and distribution of NIH with intravascular ultrasound (IVUS) after coronary artery stenting with sirolimus......-eluting (Cypher) or paclitaxel-eluting (Taxus) stents in diabetic patients. METHODS AND RESULTS: One hundred and thirty diabetic patients were randomized to Cypher or Taxus stent implantation. IVUS was performed at 8 month follow-up. NIH volume was significantly reduced in the Cypher group when compared...

  18. Radiographic stents: integrating treatment planning and implant placement.

    Science.gov (United States)

    De Kok, Ingeborg J; Thalji, Ghadeer; Bryington, Matthew; Cooper, Lyndon F

    2014-01-01

    The pivotal point in treatment planning for dental implants occurs when the location of bone is viewed radiographically in the context of the planned prosthesis. Radiographic planning for dental implant therapy should be used only after a review of the patient's systemic health, imaging history, oral health, and local oral conditions. The radiological diagnostic and planning procedure for dental implants can only be fully achieved with the use of a well-designed and -constructed radiographic guide. This article reviews several methods for construction of radiographic guides and how they may be utilized for improving implant surgery planning and performance. Copyright © 2014 Elsevier Inc. All rights reserved.

  19. Study of the relationship between the indication rod of stent on implant CT and the real path of implant fixture insertion considering residual ridge

    International Nuclear Information System (INIS)

    Kim, Do Hoon; Heo, Min Suk; Lee, Sam Sun; Oh, Sung Ook; Choi, Soon Chul; Choi, Hang Moon; Jeon, In Seong

    2003-01-01

    To assess the relationship between the direction of the indicating rod of the radiographic stent for ideal prosthetic design and the actual possible path of implant fixture placement when residual ridge resorption is considered. The study materials considered of 326 implant sites (male 214 cases and female 112 cases) from a total of 106 patients (male 65 patients and female 41 patients) who desired implant prostheses. Computed tomography of patients were taken and reformatted using ToothPix software. Bony defects, bony sclerosis, the change of the direction of indicating rod, and root proximity of the adjacent teeth were examined on the CT-derived images. The rate of the irregular crestal cortex was relatively high on premolar and molar area of maxilla. Mandibular molar area showed relatively high rate of focal sclerosis on the area of implant fixture insertion. The position of the including rods were relatively acceptable on the molar areas of both jaws. However, the position of the indicating rods should be shifted to buccal side with lingual rotation of the apical end on maxillary anterior teeth and premolar area. Clinically determined rod direction and position of the indicating rod for implant placement was not always acceptable for insertion according to the reformatted CT images. The pre-operative treatment plan for implant should be determined carefully, considering the state of the alveolar bone using the reformatted CT images.

  20. Use of rapid prototyping models in the planning of percutaneous pulmonary valved stent implantation.

    Science.gov (United States)

    Armillotta, A; Bonhoeffer, P; Dubini, G; Ferragina, S; Migliavacca, F; Sala, G; Schievano, S

    2007-05-01

    Percutaneous replacement of the pulmonary valve is a recently developed interventional technique which involves the implantation of a valved stent in the pulmonary trunk. It relies upon careful consideration of patient anatomy for both stent design and detailed procedure planning. Medical imaging data in the form of two-dimensional scans and three-dimensional interactive graphics offer only limited support for these tasks. The paper reports the results of an experimental investigation on the use of arterial models built by rapid prototyping techniques. An analysis of clinical needs has helped to specify proper requirements for such model properties as cost, strength, accuracy, elastic compliance, and optical transparency. Two different process chains, based on the fused deposition modelling technique and on the vacuum casting of thermoset resins in rubber moulds, have been tested for prototype fabrication. The use of anatomical models has allowed the cardiologist's confidence in patient selection, prosthesis fabrication, and final implantation to be significantly improved.

  1. Randomized comparison between intracoronary β-radiation brachytherapy and implantation of paclitaxel-eluting stents for the treatment of diffuse in-stent restenosis

    International Nuclear Information System (INIS)

    Schukro, Christoph; Syeda, Bonni; Kirisits, Christian; Schmid, Rainer; Pichler, Philipp; Pokrajac, Boris; Lang, Irene; Poetter, Richard; Glogar, Dietmar

    2007-01-01

    Background and purpose: Intracoronary brachytherapy was the primary therapeutic option for the treatment of in-stent restenosis (ISR) during the last years. Especially for the treatment of diffuse ISR (lesions >10 mm), β-source brachytherapy was significantly superior to singular balloon angioplasty. Despite lacking clinical database, the implantation of drug eluting stents recently became a common procedure for the treatment of ISR. This randomized trial aimed to compare the efficacy of β-brachytherapy with β-radioisotopes 90 Sr/ 90 Y and paclitaxel-eluting stent implantation for the treatment of diffuse ISR. Material and methods: Thirty-seven patients with diffuse ISR were randomly assigned to β-brachytherapy after balloon angioplasty (Beta-Cath TM in 17 patients) or paclitaxel-eluting stent implantation (Taxus-Express2 TM in 20 patients). Six-month clinical follow-up was obtained for all patients, while angiographic follow-up was available for 30 patients. Results: Binary ISR (restenosis >50%) within target segment was observed in three patients treated with Beta-Cath TM , of which one needed target segment revascularisation for recurrent ISR, whereas no significant restenosis occurred in the patients treated with Taxus-Express2 TM (P = 0.037). No further major adverse cardiac (target segment revascularisation, myocardial infarction, death) was found in either group (P = NS). Stent implantation was the more time-saving (31 ± 11 min versus 60 ± 23 min, P TM arm, we found no difference in clinical outcome after implantation of paclitaxel-eluting stents for the treatment of diffuse ISR when compared to β-brachytherapy

  2. Implantation of the Corinthian IQ stent into the femoropopliteal arteries using 6-F introducer sheaths in antegrade and crossover procedures: midterm results

    International Nuclear Information System (INIS)

    Dorffner, Roland; Neumann, Christian; Gergely, Istvan; Renner, Reinhold; Resinger, Mathias; Juhasz, Max; Dorffner, Georg

    2003-01-01

    The aim of this study was to evaluate the technical performance of the implantation of the Corinthian IQ stent into the femoropopliteal arteries using 6-F introducer sheaths. Thirty-three lesions (24 stenoses, 9 occlusions) in 32 patients (mean age 67 years) were stented. Selective stent implantation was performed after unsatisfactory percutaneous transluminal angioplasty result with an antegrade access in 21 patients and through a crossover sheath in 11 patients. A total of 36 stents were implanted. Stent delivery was successful in all cases (stent diameter 5 or 6 mm, stent length 11-38 mm). In none of the cases was stent dislodgement from the balloon observed. Stent placement was optimal without residual stenosis in 30 cases. In 1 case the stent was chosen too short requiring implantation of a second stent. In 1 patient distal embolization was observed which was treated with catheter embolectomy. Nine-month primary and secondary patency rates were 79±8.7 and 86±7.7%, respectively. Implantation of the Corinthian IQ stent into the femoropopliteal arteries using 6-F introducer sheaths is safe in antegrade and crossover procedures. (orig.)

  3. Implantation of the Corinthian IQ stent into the femoropopliteal arteries using 6-F introducer sheaths in antegrade and crossover procedures: midterm results

    Energy Technology Data Exchange (ETDEWEB)

    Dorffner, Roland; Neumann, Christian; Gergely, Istvan [Department of Radiology, Hospital of the Brothers of St. John, Esterhazystrasse 26, 7000, Eisenstadt (Austria); Renner, Reinhold; Resinger, Mathias [Department of Surgery, Hospital of the Brothers of St. John, Esterhazystrasse 26, 7000, Eisenstadt (Austria); Juhasz, Max [Department of Internal Medicine, Hospital of the Brothers of St. John, Esterhazystrasse 26, 7000, Eisenstadt (Austria); Dorffner, Georg [Department of Medical Cybernetics and Artificial Intelligence, University of Vienna, Freyung 6/2, 1010, Vienna (Austria)

    2003-11-01

    The aim of this study was to evaluate the technical performance of the implantation of the Corinthian IQ stent into the femoropopliteal arteries using 6-F introducer sheaths. Thirty-three lesions (24 stenoses, 9 occlusions) in 32 patients (mean age 67 years) were stented. Selective stent implantation was performed after unsatisfactory percutaneous transluminal angioplasty result with an antegrade access in 21 patients and through a crossover sheath in 11 patients. A total of 36 stents were implanted. Stent delivery was successful in all cases (stent diameter 5 or 6 mm, stent length 11-38 mm). In none of the cases was stent dislodgement from the balloon observed. Stent placement was optimal without residual stenosis in 30 cases. In 1 case the stent was chosen too short requiring implantation of a second stent. In 1 patient distal embolization was observed which was treated with catheter embolectomy. Nine-month primary and secondary patency rates were 79{+-}8.7 and 86{+-}7.7%, respectively. Implantation of the Corinthian IQ stent into the femoropopliteal arteries using 6-F introducer sheaths is safe in antegrade and crossover procedures. (orig.)

  4. Computational Fluid Dynamics Simulation of Hemodynamic Alterations in Sigmoid Sinus Diverticulum and Ipsilateral Upstream Sinus Stenosis After Stent Implantation in Patients with Pulsatile Tinnitus.

    Science.gov (United States)

    Han, Yanjing; Yang, Qingqing; Yang, Zeran; Xia, Jun; Su, Tianhao; Yu, Jianan; Jin, Long; Qiao, Aike

    2017-10-01

    To investigate the relationships between upstream venous sinus stenosis and pulsatile tinnitus (PT), and to assess the correlation with diverticulum growth and the effectiveness of stent implantation. Patient-specific geometric models were constructed using computed tomography venography images from a patient with PT, with sigmoid sinus diverticulum, and with upstream transverse sinus stenosis, in whom stenting of the upstream sinus stenosis alone achieved complete remission of PT. Computational fluid dynamics simulation based on this patient-specific geometry was performed using commercially available finite element software (ANSYS-14) to qualitatively and quantitatively compare the flow velocity, flow rate, velocity vector, pressure, vorticity, and wall shear stress on the affected side transverse and sigmoid sinuses, before and after stent implantation. Stenting improved the flow direction and magnitude. After stenting, the flow pattern became smoother and more regular. High-speed blood flow at the level of the diverticulum neck was confined to a smaller area, and its direction changed from approximately perpendicular to the diverticular dome to the distal side of the diverticular neck. The diverticulum showed obvious flow reduction, with decreases of 80.7%, 68.7%, 96.1%, and 91.3% in peak velocity, inflow rate, pressure gradient, and peak vorticity, respectively. The abnormally low wall shear stress at the dome of diverticulum was eliminated. Our findings strongly support a major role of diverticulum stenosis before in PT development and suggest that such stenosis is a causative factor of diverticulum growth. They also confirm the effectiveness of stent implantation for the treatment of PT. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Retrograde Colonic Stent Implantation Assisted by Percutaneous Colostomy: A Case Report

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Hyoung Gun; Han, Hyun Young; Chun, Tong Jin [Eulji Medical Center, Seoul (Korea, Republic of)

    2009-10-15

    We present a patient with disseminated pancreatic cancer who presented with symptoms of acute obstruction of the sigmoid colon. It was not possible to pass the region of the obstruction with a guide wire under colonoscopy and fluoroscopy. Consequently retrograde implantation of stents was performed successfully with the assistance of a minimally-sized colostomy when compared with a previously described procedure in the literature.

  6. Concomitant use of clopidogrel and statins and risk of major adverse cardiovascular events following coronary stent implantation

    DEFF Research Database (Denmark)

    Schmidt, Morten Hvid; Johansen, Martin B; Maeng, Michael

    2012-01-01

    quantification of the interaction effect. WHAT THIS STUDY ADDS • Clopidogrel and CYP3A4-metabolizing statin use were each associated with a substantially reduced rate of major adverse cardiovascular events within 12 months after coronary stent implantation. • Although we observed an interaction between use...... of clopidogrel and statins, statin use vs. non-use was not associated with an increased rate of major adverse cardiovascular events in patients using clopidogrel after coronary stent implantation. AIMS To examine whether CYP3A4-metabolizing statin use modified the association between clopidogrel use and major...... adverse cardiovascular events (MACE) after coronary stent implantation, using time-varying drug exposure ascertainment. METHODS We conducted this population-based cohort study in Western Denmark (population: 3 million) using medical databases. We identified all 13 001 patients with coronary stent...

  7. 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

    2013-01-01

    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...

  8. The influence of coronary plaque morphology assessed by optical coherence tomography on final microvascular function after stenting in patients with ST-elevation myocardial infarction.

    Science.gov (United States)

    De Maria, Giovanni L; Patel, Niket; Wolfrum, Mathias; Fahrni, Gregor; Kassimis, George; Porto, Italo; Dawkins, Sam; Choudhury, Robin P; Forfar, John C; Prendergast, Bernard D; Channon, Keith M; Kharbanda, Rajesh K; Garcia-Garcia, Hector M; Banning, Adrian P

    2017-05-01

    The index of microcirculatory resistance (IMR) provides a reproducible assessment of the status of coronary microvasculature in patients with ST-elevation myocardial infarction (STEMI). Frequency-domain optical coherence tomography (FD-OCT) enables detailed assessment of the morphology of coronary plaque.We sought to determine the influence of the initial culprit coronary plaque anatomy within the infarct-related artery on IMR after stenting in STEMI. In 25 STEMI patients IMR was measured immediately before and after stent implantation. FD-OCT imaging was performed at the same time points and atherothrombotic volume (ATV) before stenting, prolapsed+floating ATV after stenting and ΔATV was measured using three different strategies. There were no relationships between preprocedural IMR and FD-OCT parameters. Prestenting IMR was related only to pain to wire time (P: 0.02). Irrespective of the method adopted, the final IMR was related to prestenting ATV (ρ: 0.44, P: 0.03 for method I, ρ: 0.48, P: 0.02 for method II and ρ: 0.30, P: 0.06 for method III) and ΔATV (ρ: 0.41, P: 0.04 for method II and ρ: 0.44, P: 0.03 for method III). IMR measured before stenting is independent of the appearances of the culprit coronary plaque within the infarct-related artery. IMR after stenting, and more importantly, the change in IMR after stenting, reflect the degree of distal embolization during stent implantation.

  9. Stent Implantation for Superior Vena Cava Syndrome of Malignant Cause.

    Science.gov (United States)

    Büstgens, Felix A; Loose, Reinhard; Ficker, Joachim H; Wucherer, Michael; Uder, Michael; Adamus, Ralf

    2017-05-01

    Purpose  The purpose of this paper is the retrospective analysis of endovascular therapy for the treatment of superior vena cava syndrome (SVCS) of malignant cause. This study focuses on the effectiveness of the therapy regarding the duration of remission, symptom control and practicability. Materials and Methods  From January 2003 to November 2012, therapeutic implantation of one or more stents was performed in 141 patients suffering from SVCS. The medical history was retrospectively researched using digitalized patient files. If those were incomplete, secondary research was conducted using the cancer registry of the General Hospital Nuremberg, the cancer registry of the tumor center at Friedrich-Alexander-University Erlangen-Nuremberg (FAU) or information given by physicians in private practice. This data was collected using Microsoft Office Excel ® and statistically analyzed using IBM SPSS Statistics 22 ® . Results  168 stents were implanted in 141 patients (median age: 64.6 years; range: 36 - 84), 86 being male and 55 being female. In 121 patients, SVCS was caused by lung cancer (85.8 %), in 9 patients by mediastinal metastasis of an extrathoracic carcinoma (6.4 %), in 3 patients by mesothelioma of the pleura (2.1 %) and in 1 patient by Hodgkin's disease (0.7 %). There was no histological diagnosis in 7 cases (4.9 %). The primary intervention was successful in 138 patients (97.9 %). Immediate thrombosis in the stent occurred in the remaining 3 cases. Recurrence of SVCS was observed in 22 patients (15.6 %), including 5 early and 17 late occlusions. Stent dislocation or breakage was not observed. As expected, the survival after implantation was poor. The median survival was 101 days, and the median occlusion-free survival was 80 days. Conclusion  The symptomatic therapy of SVCS with endovascular stents is effective and safe. Despite effective symptom control and a low rate of recurrence, the patients' prognosis is poor. Key

  10. First follow-up of a breakable stent for implantation in infants dedicated for a life-long stay.

    Science.gov (United States)

    Zartner, Peter A; Neudorf, Ulrich; Bierbach, Benjamin; Hart, Chris; Schneider, Martin B

    2018-02-22

    The use of conventional metal stents in infants is severely limited by subsequent somatic growth. The use of a breakable balloon expandable stent (BS) designed for initial implant at small diameters but with properties that allow unlimited dilation in line with growth has potential advantages in this patient group. This study reports our experience with this stent between 2010 and 2014. A total of 17 BS were implanted in 14 infants (mean age 4.8 months). All but one stent was placed into the aorta to treat coarctation. All implantations were successful and initial gradients dropped from a mean of 25-6 mm Hg (range from 1-50 down to 0-24 mm Hg). Mean follow-up was 3.3 years (range 5 days to 7 years) with a total cumulative follow-up of 46.7 patient years. Stent redilation was performed a median of 2.5 times (range 0-5). Sixteen stents in 13 patients remain in place. Following redilation beyond 10 mm, circumferential integrity of the BS was lost in 10 patients. No further stent implantation or related surgery was necessary. A 3 mm dissection occurred in one patient after redilation. The BS performed well in terms of relief of stenosis and could be successfully dilated during the phase of the infants' most rapid growth. Mild intimal proliferation occurred in some patients early after implantation. In the course of the stepwise redilations and growth adjustments, both, planned longitudinal and transverse fractures occurred without allowing a collapse of the stented area. © 2018 Wiley Periodicals, Inc.

  11. Prognostic Value of Plasma Pentraxin-3 Levels in Patients with Stable Coronary Artery Disease after Drug-Eluting Stent Implantation

    Directory of Open Access Journals (Sweden)

    Liu Haibo

    2014-01-01

    Full Text Available Pentraxin-3 (PTX3 is an inflammatory marker thought to be more specific to cardiovascular inflammation than C-reactive protein (CRP. Our aim was to assess the prognostic value of PTX3 in patients with stable coronary artery disease (CAD after drug eluting stent (DES implantation. Plasma PTX3 levels were measured before percutaneous coronary intervention (PCI and at 24 h post-PCI in 596 consecutive patients with stable CAD. Patients were followed up for a median of 3 years (range 1–5 for major adverse cardiovascular events (MACEs. We found that the post-PCI plasma PTX3 levels were significantly higher at 24 h after PCI than pre-PCI, patients with MACEs had higher post-PCI PTX3 levels compared with MACEs-free patients, patients with higher post-PCI PTX3 levels (median > 4.384 ng/mL had a higher risk for MACEs than those with PTX3 < 4.384 ng/mL, and post-PCI PTX3, cTnI, multiple stents, and age but not high-sensitivity CRP (hsCRP were independently associated with the prevalence of MACEs after DES implantation. The present study shows that post-PCI PTX3 may be a more reliable inflammatory predictor of long-term MACEs in patients with stable CAD undergoing DES implantation than CRP. Measurement of post-PCI PTX3 levels could provide a rationale for risk stratification of patients with stable CAD after DES implantation.

  12. Surface modification of coronary artery stent by Ti-O/Ti-N complex film coating prepared with plasma immersion ion implantation and deposition

    International Nuclear Information System (INIS)

    Huang, N.; Leng, Y.X.; Yang, P.

    2006-01-01

    This paper reported the work of surface coating of Ti-O/Ti-N complex films on coronary stents by means of the plasma immersion ion implantation/deposition process. The deformation behavior of the Ti-O/Ti-N coated stainless steel stents was investigated. In vivo investigation of the anticoagulation behavior of Ti-O coated coronary stents was also performed. The results of mechanical characterization of the Ti-O/Ti-N coated stents show that the film has strong binding strength, and to some extent the ability to withstand plastic deformation. The biological response behavior of the coated stent surface was significantly different from the uncoated. The results of implantation of stents into rabbit ventral aorta show no thrombus formation on the surfaces of the Ti-O coated stents, although serious coagulation had occurred on the surfaces of unmodified stents over a period of 4 weeks under conditions with no anticoagulant

  13. In-vitro study on the accuracy of a simple-design CT-guided stent for dental implants

    International Nuclear Information System (INIS)

    Huh, Young June; Choi, Bo Ram; Huh, Kyung Hoe; Yi, Won Jin; Heo, Min Suk; Lee, Sam Sun; Choi, Soon Chul

    2012-01-01

    An individual surgical stent fabricated from computed tomography (CT) data, called a CT-guided stent, would be useful for accurate installation of implants. The purpose of the present study was to introduce a newly developed CT-guided stent with a simple design and evaluate the accuracy of the stent placement. A resin template was fabricated from a hog mandible and a specially designed plastic plate, with 4 metal balls inserted in it for radiographic recognition, was attached to the occlusal surface of the template. With the surgical stent applied, CT images were taken, and virtual implants were placed using software. The spatial positions of the virtually positioned implants were acquired and implant guiding holes were drilled into the surgical stent using a specially designed 5-axis drilling machine. The surgical stent was placed on the mandible and CT images were taken again. The discrepancy between the central axis of the drilled holes on the second CT images and the virtually installed implants on the first CT images was evaluated. The deviation of the entry point and angulation of the central axis in the reference plane were 0.47±0.27 mm, 0.57±0.23 mm, and 0.64±0.16 degree, 0.57±0.15 degree, respectively. However, for the two different angulations in each group, the 20 degree angulation showed a greater error in the deviation of the entry point than did the 10 degree angulation. The CT-guided template proposed in this study was highly accurate. It could replace existing implant guide systems to reduce costs and effort.

  14. In-vitro study on the accuracy of a simple-design CT-guided stent for dental implants

    Energy Technology Data Exchange (ETDEWEB)

    Huh, Young June; Choi, Bo Ram; Huh, Kyung Hoe; Yi, Won Jin; Heo, Min Suk; Lee, Sam Sun; Choi, Soon Chul [School of Dentistry, Seoul National University, Seoul (Korea, Republic of)

    2012-09-15

    An individual surgical stent fabricated from computed tomography (CT) data, called a CT-guided stent, would be useful for accurate installation of implants. The purpose of the present study was to introduce a newly developed CT-guided stent with a simple design and evaluate the accuracy of the stent placement. A resin template was fabricated from a hog mandible and a specially designed plastic plate, with 4 metal balls inserted in it for radiographic recognition, was attached to the occlusal surface of the template. With the surgical stent applied, CT images were taken, and virtual implants were placed using software. The spatial positions of the virtually positioned implants were acquired and implant guiding holes were drilled into the surgical stent using a specially designed 5-axis drilling machine. The surgical stent was placed on the mandible and CT images were taken again. The discrepancy between the central axis of the drilled holes on the second CT images and the virtually installed implants on the first CT images was evaluated. The deviation of the entry point and angulation of the central axis in the reference plane were 0.47{+-}0.27 mm, 0.57{+-}0.23 mm, and 0.64{+-}0.16 degree, 0.57{+-}0.15 degree, respectively. However, for the two different angulations in each group, the 20 degree angulation showed a greater error in the deviation of the entry point than did the 10 degree angulation. The CT-guided template proposed in this study was highly accurate. It could replace existing implant guide systems to reduce costs and effort.

  15. Stent valve implantation in conventional redo aortic valve surgery to prevent patient-prosthesis mismatch.

    Science.gov (United States)

    Ferrari, Enrico; Franciosi, Giorgio; Clivio, Sara; Faletra, Francesco; Moccetti, Marco; Moccetti, Tiziano; Pedrazzini, Giovanni; Demertzis, Stefanos

    2017-03-01

    The goal was to show the technical details, feasibility and clinical results of balloon-expandable stent valve implantation in the aortic position during conventional redo open-heart surgery in selected obese patients with a small aortic prosthesis and severe patient-prosthesis mismatch. Two symptomatic overweight patients (body mass index of 31 and 38), each with a small aortic prosthesis (a 4-year-old, 21-mm Hancock II biological valve and a 29-year-old, 23-mm Duromedic mechanical valve), increased transvalvular gradients (59/31 and 74/44 mmHg) and a reduced indexed effective orifice area (0.50 and 0.43 cm 2 /m 2 ) underwent implantation of two 26-mm balloon-expandable Sapien 3 valves during standard on-pump redo valve surgery. Using full re-sternotomy, cardiopulmonary bypass and cardioplegic arrest, the two balloon-expandable stent valves were implanted under direct view using a standard aortotomy, after prosthesis removal and without annulus enlargement. Aortic cross-clamp times were 162 and 126 min; cardiopulmonary bypass times were 178 and 180 min; total surgical times were 360 and 318 min. At discharge, echocardiograms showed transvalvular peak and mean gradients of 13/9 and 23/13 mmHg and indexed effective orifice areas of 0.64 and 1.08 cm 2 /m 2 . The 3-month echocardiographic follow-up showed transvalvular peak and mean gradients of 18/9 and 19/11 mmHg and indexed effective orifice areas of 0.78 cm 2 /m 2 and 0.84 cm 2 /m 2 , with improved symptoms (New York Heart Association class 1). Implantation of a balloon-expandable stent valve during redo aortic valve surgery is feasible in selected cases and prevents patient-prosthesis mismatch in obese patients without need for aortic annulus enlargement. Moreover, in the case of stent valve degeneration, this approach permits additional valve-in-valve procedures with large stent valves and prevents re-redo surgery. © The Author 2016. Published by Oxford University Press on behalf of the

  16. Technical feasibility of the implantation of a monorail stent system into the renal arteries without pre-dilatation; Technische Machbarkeit der Implantation eines Monorail-Stent-Systems in die Nierenarterien ohne vorherige Dilatation

    Energy Technology Data Exchange (ETDEWEB)

    Neumann, C.; Dorffner, R. [Krankenhaus der Barmherzigen Brueder, Eisenstadt, Oesterreich (Austria); Gschwendtner, M. [Krankenhaus der Elisabethinen, Linz, Oesterreich (Austria); Karnel, F. [Kaiser-Franz-Josef-Spital, Wien, Oesterreich (Austria); Mair, J. [Krankenhaus der Barmherzigen Schwestern, Linz, Oesterreich (Austria); Dorffner, G. [Inst. fuer Medizinische Kybernetik und Artificial Intelligence, Medizinische Univ. Wien, Oesterreich (Austria)

    2005-01-01

    Purpose: to evaluate the technical feasibility of the implantation of the monorail RX Herculink trademark system into the renal arteries without pre-dilatation. Materials and methods: forty-two patients (mean age 71 years) from four centers with a total of 44 renal artery stenoses underwent implantation of the RX Herculink trademark stent. The mean grade of the stenosis was 83.8%, the mean length 7.5 mm. The stenoses were ostial in 38 cases and in immediate proximity to the ostium in 6 cases. The mean follow-up-period was 57 weeks (24 - 176 weeks). Results: in 42 cases, the implantation was successful without pre-dilatation. In 2 cases, pre-dilatation was carried out. In none of the cases, detachment of the stent from the balloon was observed. In one stenosis with a length of 17 mm, implantation of two stents was performed. In 9 cases, post-dilatation with a larger balloon or higher balloon pressure was necessary. Residual stenoses exceeding 30% were not observed. Two patients developed local bleeding at the puncture site. During the follow-up, restenoses were observed in 5 stents after 26 to 126 weeks, which necessitated a second intervention in 3 cases (PTA in 2 cases, re-stenting in 1 case). The primary patency rate after 6 and 12 months was 0.92 {+-} 0.056 according to Kaplan-Meier, the secondary patency rate after 6 and 12 months was 1.0 {+-} 0.0. Conclusion: implantation of the RX Herculink trademark stent system into the renal arteries without pre-dilatation is technically feasible and safe. Even without pre-dilatation, the stent-system can be advanced through the stenosis without detachment. The complication rate is low. Our clinical results are comparable to previous studies. (orig.)

  17. Intravascular ultrasound assessment of expansion of the sirolimus-eluting (Cypher Select) and paclitaxel-eluting (Taxus Express-2) stent in patients with diabetes mellitus

    DEFF Research Database (Denmark)

    Jensen, L.O.; Maeng, M.; Mintz, G.S.

    2008-01-01

    Patients with diabetes have a higher risk for in-stent restenosis after coronary stent implantation. Drug-eluting stents (DES) are highly effective in reducing in-stent restenosis. Once neointimal hyperplasia is suppressed with DES, the impact of stent underexpansion becomes magnified. The aim of...

  18. Expansion of the Multi-Link Frontier™ Coronary Bifurcation Stent: Micro-Computed Tomographic Assessment in Human Autopsy and Porcine Heart Samples

    Science.gov (United States)

    Kralev, Stefan; Haag, Benjamin; Spannenberger, Jens; Lang, Siegfried; Brockmann, Marc A.; Bartling, Soenke; Marx, Alexander; Haase, Karl-Konstantin; Borggrefe, Martin; Süselbeck, Tim

    2011-01-01

    Background Treatment of coronary bifurcation lesions remains challenging, beyond the introduction of drug eluting stents. Dedicated stent systems are available to improve the technical approach to the treatment of these lesions. However dedicated stent systems have so far not reduced the incidence of stent restenosis. The aim of this study was to assess the expansion of the Multi-Link (ML) Frontier™ stent in human and porcine coronary arteries to provide the cardiologist with useful in-vitro information for stent implantation and selection. Methodology/Principal Findings Nine ML Frontier™ stents were implanted in seven human autopsy heart samples with known coronary artery disease and five ML Frontier™ stents were implanted in five porcine hearts. Proximal, distal and side branch diameters (PD, DD, SBD, respectively), corresponding opening areas (PA, DA, SBA) and the mean stent length (L) were assessed by micro-computed tomography (micro-CT). PD and PA were significantly smaller in human autopsy heart samples than in porcine heart samples (3.54±0.47 mm vs. 4.04±0.22 mm, p = 0.048; 10.00±2.42 mm2 vs. 12.84±1.38 mm2, p = 0.034, respectively) and than those given by the manufacturer (3.54±0.47 mm vs. 4.03 mm, p = 0.014). L was smaller in human autopsy heart samples than in porcine heart samples, although data did not reach significance (16.66±1.30 mm vs. 17.30±0.51 mm, p = 0.32), and significantly smaller than that given by the manufacturer (16.66±1.30 mm vs. 18 mm, p = 0.015). Conclusions/Significance Micro-CT is a feasible tool for exact surveying of dedicated stent systems and could make a contribution to the development of these devices. The proximal diameter and proximal area of the stent system were considerably smaller in human autopsy heart samples than in porcine heart samples and than those given by the manufacturer. Special consideration should be given to the stent deployment procedure (and to the follow-up) of dedicated

  19. Expansion of the Multi-Link Frontier™ coronary bifurcation stent: micro-computed tomographic assessment in human autopsy and porcine heart samples.

    Directory of Open Access Journals (Sweden)

    Stefan Kralev

    Full Text Available BACKGROUND: Treatment of coronary bifurcation lesions remains challenging, beyond the introduction of drug eluting stents. Dedicated stent systems are available to improve the technical approach to the treatment of these lesions. However dedicated stent systems have so far not reduced the incidence of stent restenosis. The aim of this study was to assess the expansion of the Multi-Link (ML Frontier™ stent in human and porcine coronary arteries to provide the cardiologist with useful in-vitro information for stent implantation and selection. METHODOLOGY/PRINCIPAL FINDINGS: Nine ML Frontier™ stents were implanted in seven human autopsy heart samples with known coronary artery disease and five ML Frontier™ stents were implanted in five porcine hearts. Proximal, distal and side branch diameters (PD, DD, SBD, respectively, corresponding opening areas (PA, DA, SBA and the mean stent length (L were assessed by micro-computed tomography (micro-CT. PD and PA were significantly smaller in human autopsy heart samples than in porcine heart samples (3.54±0.47 mm vs. 4.04±0.22 mm, p = 0.048; 10.00±2.42 mm(2 vs. 12.84±1.38 mm(2, p = 0.034, respectively and than those given by the manufacturer (3.54±0.47 mm vs. 4.03 mm, p = 0.014. L was smaller in human autopsy heart samples than in porcine heart samples, although data did not reach significance (16.66±1.30 mm vs. 17.30±0.51 mm, p = 0.32, and significantly smaller than that given by the manufacturer (16.66±1.30 mm vs. 18 mm, p = 0.015. CONCLUSIONS/SIGNIFICANCE: Micro-CT is a feasible tool for exact surveying of dedicated stent systems and could make a contribution to the development of these devices. The proximal diameter and proximal area of the stent system were considerably smaller in human autopsy heart samples than in porcine heart samples and than those given by the manufacturer. Special consideration should be given to the stent deployment procedure (and to the follow

  20. Expansion of the Multi-Link Frontier™ coronary bifurcation stent: micro-computed tomographic assessment in human autopsy and porcine heart samples.

    Science.gov (United States)

    Kralev, Stefan; Haag, Benjamin; Spannenberger, Jens; Lang, Siegfried; Brockmann, Marc A; Bartling, Soenke; Marx, Alexander; Haase, Karl-Konstantin; Borggrefe, Martin; Süselbeck, Tim

    2011-01-01

    Treatment of coronary bifurcation lesions remains challenging, beyond the introduction of drug eluting stents. Dedicated stent systems are available to improve the technical approach to the treatment of these lesions. However dedicated stent systems have so far not reduced the incidence of stent restenosis. The aim of this study was to assess the expansion of the Multi-Link (ML) Frontier™ stent in human and porcine coronary arteries to provide the cardiologist with useful in-vitro information for stent implantation and selection. Nine ML Frontier™ stents were implanted in seven human autopsy heart samples with known coronary artery disease and five ML Frontier™ stents were implanted in five porcine hearts. Proximal, distal and side branch diameters (PD, DD, SBD, respectively), corresponding opening areas (PA, DA, SBA) and the mean stent length (L) were assessed by micro-computed tomography (micro-CT). PD and PA were significantly smaller in human autopsy heart samples than in porcine heart samples (3.54±0.47 mm vs. 4.04±0.22 mm, p = 0.048; 10.00±2.42 mm(2) vs. 12.84±1.38 mm(2), p = 0.034, respectively) and than those given by the manufacturer (3.54±0.47 mm vs. 4.03 mm, p = 0.014). L was smaller in human autopsy heart samples than in porcine heart samples, although data did not reach significance (16.66±1.30 mm vs. 17.30±0.51 mm, p = 0.32), and significantly smaller than that given by the manufacturer (16.66±1.30 mm vs. 18 mm, p = 0.015). Micro-CT is a feasible tool for exact surveying of dedicated stent systems and could make a contribution to the development of these devices. The proximal diameter and proximal area of the stent system were considerably smaller in human autopsy heart samples than in porcine heart samples and than those given by the manufacturer. Special consideration should be given to the stent deployment procedure (and to the follow-up) of dedicated stent systems, considering final intravascular ultrasound or

  1. Technical feasibility of the implantation of a monorail stent system into the renal arteries without pre-dilatation

    International Nuclear Information System (INIS)

    Neumann, C.; Dorffner, R.; Gschwendtner, M.; Karnel, F.; Mair, J.; Dorffner, G.

    2005-01-01

    Purpose: to evaluate the technical feasibility of the implantation of the monorail RX Herculink trademark system into the renal arteries without pre-dilatation. Materials and methods: forty-two patients (mean age 71 years) from four centers with a total of 44 renal artery stenoses underwent implantation of the RX Herculink trademark stent. The mean grade of the stenosis was 83.8%, the mean length 7.5 mm. The stenoses were ostial in 38 cases and in immediate proximity to the ostium in 6 cases. The mean follow-up-period was 57 weeks (24 - 176 weeks). Results: in 42 cases, the implantation was successful without pre-dilatation. In 2 cases, pre-dilatation was carried out. In none of the cases, detachment of the stent from the balloon was observed. In one stenosis with a length of 17 mm, implantation of two stents was performed. In 9 cases, post-dilatation with a larger balloon or higher balloon pressure was necessary. Residual stenoses exceeding 30% were not observed. Two patients developed local bleeding at the puncture site. During the follow-up, restenoses were observed in 5 stents after 26 to 126 weeks, which necessitated a second intervention in 3 cases (PTA in 2 cases, re-stenting in 1 case). The primary patency rate after 6 and 12 months was 0.92 ± 0.056 according to Kaplan-Meier, the secondary patency rate after 6 and 12 months was 1.0 ± 0.0. Conclusion: implantation of the RX Herculink trademark stent system into the renal arteries without pre-dilatation is technically feasible and safe. Even without pre-dilatation, the stent-system can be advanced through the stenosis without detachment. The complication rate is low. Our clinical results are comparable to previous studies. (orig.)

  2. Angioplastia e implante de stent en pacientes con estenosis de la arteria renal Angioplasty and stent implantation in patients with renal artery stenosis

    Directory of Open Access Journals (Sweden)

    Nabil Hamdan

    2005-06-01

    Full Text Available Introducción y objetivos: la enfermedad aterosclerótica de las arterias renales se considera como una causa común de hipertensión arterial sistémica e insuficiencia renal. El tratamiento percutáneo es un procedimiento seguro, de baja morbilidad y mortalidad, y con alta tasa de éxito. Permite controlar o curar la hipertensión arterial sistémica y estabilizar la función renal (10. En este trabajo se evaluará la eficacia de la angioplastia con implante de stent en pacientes con estenosis significativa de la arteria renal. Materiales y métodos: estudio de cohorte histórico, en el cual se incluyeron 28 pacientes con estenosis significativa de la arteria renal, quienes fueron tratados con angioplastia e implante de stent, entre el 1º de enero de 2001 y el 31 de diciembre de 2003. Se realizó seguimiento clínico intrahospitalario a 12 meses en el cual se evaluaron como objetivos primarios la evolución de la hipertensión arterial y la función renal. Resultados: luego de la intervención percutánea durante la hospitalización, se logró reducir de manera significativa la presión arterial, tanto sistólica de 171,5 mm Hg a 144,5 mm Hg como diastólica de 94,9 mm Hg a 80,2 mm Hg. Se controló la presión arterial en 7 (25% pacientes. La función renal de acuerdo con los niveles de creatinina sérica se mantuvo estable y se observó un discreto aumento de 1,7 mg/dL a 1,9 mg/dL. En el seguimiento a 12 meses la presión arterial sistólica se mantuvo en 142,6 mm Hg y la diastólica en 81.4 mm Hg. En 11 (39,3% pacientes se logró controlar la presión arterial. Hubo mejoría de la función renal en 5 pacientes (17,9% y deterioro renal en 5 pacientes (17,9%, de los cuales 4 requirieron hemodiálisis. La media de creatinina sérica fue de 2,01 mg/dL con un incremento de 0,31 mg/dL con respecto a los niveles basales antes de la intervención. Conclusión: el tratamiento con angioplastia e implante de stent debe considerarse como primera elecci

  3. PlA polymorphism and platelet reactivity following clopidogrel loading dose in patients undergoing coronary stent implantation.

    Science.gov (United States)

    Angiolillo, Dominick J; Fernandez-Ortiz, Antonio; Bernardo, Esther; Alfonso, Fernando; Sabaté, Manel; Fernández, Cristina; Stranieri, Chiara; Trabetti, Elisabetta; Pignatti, Pier Franco; Macaya, Carlos

    2004-01-01

    The PlA polymorphism (Leu33Pro) of the platelet glycoprotein (GP) IIIa gene has been suggested to play an important role in coronary thrombosis. In vitro studies have shown differences for this polymorphism in platelet sensitivity towards antiplatelet drugs (aspirin and abciximab), suggesting a pharmacogenetic modulation. The aim of the study was to assess the modulatory effect of the PlA polymorphism on clopidogrel-induced antiplatelet effects in 38 patients undergoing coronary stent implantation receiving a 300 mg clopidogrel loading-dose. Platelet reactivity was assessed as GPIIb/IIIa activation and P-selectin expression in platelets stimulated with 2 micromol/l adenosine diphosphate using whole blood flow cytometry. The distribution of the homozygous PlA1/A1 and heterozygous PlA1/A2 genotypes were 74 and 26%, respectively. PlA2 carriers had a higher degree of GPIIb/IIIa activation (P = 0.05) and P-selectin expression (P = 0.02) during the overall study time course and a lower antiplatelet effect to a 300 mg clopidogrel loading-dose up to 24 h following intervention (P < 0.05). In conclusion, the Pl polymorphism of the GPIIIa gene modulates platelet reactivity towards clopidogrel front loading in patients undergoing coronary stenting. This suggests the need for individualized antithrombotic regimens to optimally inhibit platelet reactivity. Copyright 2004 Lippincott Williams and Wilkins

  4. Optical coherence tomography assessment of incidence, morphological characteristics, and spontaneous healing course of edge dissections following percutaneous coronary intervention with stent implantation in patients with non-ST segment elevation myocardial infarction

    DEFF Research Database (Denmark)

    Antonsen, L.; Thayssen, P.; Hansen, H. S.

    2016-01-01

    in a non-ST segment elevation myocardial infarction (NSTEMI) patient-population. Methods: Acute vessel wall injury at the 5-mm stent adjacent distal and proximal reference segments was assessed by post-procedure OCT and intravascular ultrasound (IVUS) in n = 97 NSTEMI-patients (n = 97 lesions). Six months...... on concomitant IVUS-analysis. Morphologically, there was a significant difference in plaque type present at ED-edges vs. non-ED-edges when assessed with OCT; (1) lipid-rich and calcified plaques: 80.9% vs. 57.0%, (2) fibrous plaques: 17.0% vs. 26.7%, and (3) normal coronary vessels: 2.1% vs. 16.3%, p ....01. Plaqueburden, assessed by IVUS, was substantially larger at ED-containing borders: 54.5 +/- 10.0% vs. 43.7 +/- 11.6%, p = 0.01. Three dissections (8.6%) were incompletely healed at 6-month OCT follow-up. None of the EDs caused cardiac events during the 6-month follow-up, however, 1 ED-patient had target lesion...

  5. 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.

  6. Clinical benefits of drug-eluting stent implantation in septuagenarians with coronary artery disease

    International Nuclear Information System (INIS)

    Fang Yuehua; Shen Weifeng; Zhang Ruiyan; Zhang Jiansheng; Hu Jian; Zhang Xian; Zheng Aifang

    2005-01-01

    Objective: This study evaluated the safety and long-term outcomes of drug-eluting stents in septuagenarians with coronary artery disease. Methods: Two hundred and thirty-nine consecutive patients with coronary artery disease underwent drug-eluting stenting, including 88 patients aged ≥70 years (group A) and 151 aged <70 years (group B). Baseline clinical characteristics, procedural success rate, occurrence of cardiac events during follow-up were recorded and compared between the two groups. Results: Procedural success rate and complications were similar for the two groups. During follow-up, group A had higher recurrence rate of chest pain than group B (23.9% vs. 7.3%, P<0.001), and occurrence of cardiac events was higher in group A than in group B (5.7% vs. 2.7%, P<0.296). There was no significant difference in the frequency of restenosis between the two groups. Conclusions: Drug-eluting stent implantation for septuagenarians with coronary artery disease is safe but may have more recurrence of angina than younger ones during long-term follow-up. (authors)

  7. Serious Complication of Percutaneous Angioplasty with Stent Implantation in so Called "Chronic Cerebrospinal Venous Insufficiency" in Multiple Sclerosis Patient

    Directory of Open Access Journals (Sweden)

    Ondřej Doležal

    2012-01-01

    Full Text Available We report female patient, age 51, with clinically definitive multiple sclerosis (CDMS since 1998, who underwent two PTA procedures with stent implantation for CCSVI in 2010. Expanded disability status scale (EDSS worsened since the procedure from 4.5 to 6. Total number of three stents was implanted (two of them in the right internal jugular vein. In six month time, in 2011, patient was referred for independent examination by computer tomography (CT phlebography for right-sided neck pain. Dislocation of stents on the right side and thrombosis of left sided stent was found. Conservative approach was used so far. Our short report is showing possible complications of PTA and stenting in jugular veins in so called CCSVI and bringing information about neurological state (EDSS worsening in a subject. Continuation of stent migration in the future is probable, possibly resulting in pulmonary embolism with fatal risk for the patient. We strongly ask for restriction of PTA procedure in so called CCSVI, which concept was not proven to be relevant to MS.

  8. Clinical outcomes following bioresorbable scaffold implantation for bifurcation lesions: Overall outcomes and comparison between provisional and planned double stenting strategy.

    Science.gov (United States)

    Kawamoto, Hiroyoshi; Latib, Azeem; Ruparelia, Neil; Miyazaki, Tadashi; Sticchi, Alessandro; Naganuma, Toru; Sato, Katsumasa; Figini, Filippo; Chieffo, Alaide; Carlino, Mauro; Montorfano, Matteo; Colombo, Antonio

    2015-10-01

    The aim of this study was to investigate clinical outcomes of patients treated with a provisional stenting (PS) versus a double stenting (DS) strategy for coronary bifurcation lesions with bioresorbable scaffolds (BRS). There are limited data available with regards to outcomes following BRS implantation for bifurcation lesions. A total of 132 bifurcation lesions treated with BRS between 2012 and 2014 were analyzed. Of the total of 132 bifurcation lesions, 10 lesions were treated without crossover stenting. 99 lesions (81%) were treated with a PS strategy and 23 lesions (19%) with a DS strategy. The DS group consisted of patients with a greater number of true bifurcation lesions (PS 52.0% vs. DS 91.3%: P stenting. In the DS group, 13 lesions (57%) were treated with BRS to the side branch (SB). A hybrid stenting technique [BRS to the main branch, and metallic drug-eluting stent (DES) to the SB] was utilized in 10 (43%) lesions. Target lesion revascularization (TLR) rates were 5.5% for PS and 11.2% for DS (P = 0.49) at 1-year follow-up. Definite scaffold thrombosis did not occur at the site of any bifurcation lesion. These findings suggest that BRS implantation for bifurcation lesions is technically feasible. The rates of TLR tended to be higher in the DS group compared to when a PS strategy was employed. Larger studies are eagerly awaited to determine longer-term follow-up of this treatment strategy. © 2015 Wiley Periodicals, Inc.

  9. Late lumen loss and intima hyperplasia after sirolimus-eluting and zotarolimus-eluting stent implantation in diabetic patients: the diabetes and drug-eluting stent (DiabeDES III) angiography and intravascular ultrasound trial

    DEFF Research Database (Denmark)

    Jensen, Lisette Okkels; Maeng, Michael; Thayssen, Per

    2011-01-01

    Patients with diabetes mellitus have increased risk of in-stent restenosis after coronary stent implantation due to neointimal hyperplasia (NIH). The aim of this study was to use quantitative coronary angiography (QCA) and volumetric intravascular ultrasound (IVUS) to evaluate the effects...

  10. Clinical results of carotid artery stenting with a nitinol self-expanding stent (SMART stent)

    Energy Technology Data Exchange (ETDEWEB)

    Drescher, Robert; Mathias, Klaus D.; Jaeger, Horst J.; Bockisch, Georg; Demirel, Eren; Gissler, Martin H.; Hauth, Elke [Department of Radiology, Staedtische Kliniken Dortmund, Beurhausstrasse 40, 44139 Dortmund (Germany); Department of Radiology and Microtherapy, University Witten/Herdecke (Germany)

    2002-10-01

    Our objective was to assess the technical feasibility and the clinical results of internal carotid artery (ICA) stenting using a nitinol self-expanding stent (SMART stent). In 13 patients 13 high-grade stenoses of the internal carotid artery were treated via an implantation of a SMART stent. In all cases a predilation of the stenosis and a postdilation within the stent were performed. Follow-up examinations were carried out in all patients after a period of 6 months. In each case the implantation of the stent was performed without technical complications. In 12 of 13 cases the stent was placed in the patients' internal carotid artery, in 1 case from the internal to the common carotid artery (CCA). The average degree of stenosis of 78% (70-95%) was reduced to an average of 2.8% (0-21%). The 6-month follow-up angiography showed an average degree of restenosis of 11.8% (0-29%) in 8 of 13 patients. Duplex sonography in the remaining 5 patients demonstrated patent stents. One patient showed brief neurological symptoms during the intervention. No further complications occurred during follow-up time. Treatment of internal carotid artery stenosis with the SMART stent seems technically feasible, safe, and promises long-term patency. (orig.)

  11. Clinical Study on Using 125I Seeds Articles Combined with Biliary Stent Implantation in the Treatment of Malignant Obstructive Jaundice.

    Science.gov (United States)

    Wang, Tao; Liu, Sheng; Zheng, Yan-Bo; Song, Xue-Peng; Sun, Bo-Lin; Jiang, Wen-Jin; Wang, Li-Gang

    2017-08-01

    Aim: To study the feasibility and curative effect of 125 I seeds articles combined with biliary stent implantation in the treatment of malignant obstructive jaundice. Patients and Methods: Fifty patients with malignant obstructive jaundice were included. Twenty-four were treated by biliary stent implantation combined with intraluminal brachytherapy by 125 I seeds articles as the experimental group, while the remaining 26 were treated by biliary stent implantation only as the control group. The goal of this study was to evaluate total bilirubin, direct bilirubin and tumor markers (cancer antigen (CA)-199, CA-242 and carcinoembryonic antigen (CEA)), as well as biliary stent patency status and survival time before and after surgery. Results: Jaundice improved greatly in both groups. The decreases of CA-199 and CA-242 had statistical significance (p=0.003 and p=0.004) in the experimental group. The ratio of biliary stent patency was 83.3% (20/24) in the experimental group and 57.7% (15/26) in the control group (p=0.048). The biliary stent patency time in the experimental group was 1~15.5 (mean=9.84) months. The biliary stent patency time in the control group was 0.8~9 (mean=5.57) months, which was statistically significant (p=0.018). The median survival time was 10.2 months in the experimental group, while 5.4 months in control group (pjaundice possibly by inhibiting the proliferation of vascular endothelial cells and the growth of tumor. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

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

    Directory of Open Access Journals (Sweden)

    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

  13. 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...... emotions and tend not to express these emotions in social interactions....

  14. [In hospital and mid-term outcome of patients with NIR stent implantation: multicenter ESPORT-NIR registry].

    Science.gov (United States)

    Iñiguez, A; García, E; Seabra, R; Bordes, P; Bethencourt, A; Rigla, J

    2001-05-01

    Despite improvements in the results and techniques of catheter-based revascularization, few studies have evaluated the clinical results of the application of new stent designs. We describe the in-hospital and mid-term outcome of patients undergoing a stent NIR implantation. At least 1 Stent NIR was implanted in 1.004 patients (1.136 lesions) recruited from 50 centers in an international, multicenter, prospective, registry (Spain and Portugal NIR stent registry). Inclusion criteria were objective coronary ischemia related to a severe de novo lesion or first restenosis in native vessels with a reference diameter >= 2.75 mm. The primary end-point was the incidence of major adverse cardiac events within the first 7 months of follow-up. The mean age of the patients was 60 years and 82% were male. Angioplasty was indicated due to unstable angina in 61% of the cases. Stent implantation was successfully achieved in 99.6%. Clinical success (angiographic success without in-hospital major events) was achieved in 98.6% of patients. The rate of angiographic restenosis (> 50% stenosis narrowing) was 16% (CI 95%; 11.7-21.2). The accumulated major cardiac adverse event rate at seven months of follow-up was 8.7%: death (0.9%), acute myocardial infarction (1.2%) and target lesion revascularization (6.6%). In the wide setting of the population included in the ESPORT-NIR registry, stent NIR implantation was a highly effective therapy with a good mid-term clinical and angiographic outcome.

  15. Effects of angiotensin II and angiotensin II type 1 receptor blockade on neointimal formation after stent implantation

    NARCIS (Netherlands)

    Groenewegen, Hendrik C.; van der Harst, Pim; Roks, Anton J. M.; Buikema, Hendrik; Zijlstra, Felix; van Gilst, Wiek H.; de Smet, Bart J. G. L.

    2008-01-01

    Background: To evaluate the effect of supraphysiological levels of angiotensin II and selective angiotensin II type 1 receptor ( AT1-receptor) blockade on neointimal formation and systemic endothelial function after stent implantation in the rat abdominal aorta. Methods: Male Wistar rats were

  16. Negative vascular remodelling after implantation of bioabsorbable magnesium alloy stents in porcine coronary arteries: a randomised comparison with bare-metal and sirolimus-eluting stents

    DEFF Research Database (Denmark)

    Maeng, M; Jensen, Lisette Okkels; Falk, E

    2009-01-01

    ultrasound (IVUS). RESULTS: By histomorphometry, lumen (median (quartiles); AMS: 1.75 mm2 (1.07-3.26), Cypher 2.52 mm2 (2.22-5.01), BMS 4.55 mm2 (3.2-7.44); p = 0.013) and external elastic membrane area (AMS: 5.56 mm2 (4.09-6.95), Cypher 7.95 mm2 (6.45-10.92), BMS 9.08 mm2 (7.85-11.63); p = 0.014) were...... smallest after AMS implantation. By IVUS, external elastic membrane area at follow-up was smallest (AMS: 7.5 (2.8) mm2, Cypher 9.1 (2.7) mm2, BMS 9.9 (3.1) mm2; p = 0.33) and change in external elastic membrane area from index intervention to follow-up (remodelling; AMS: -1.0 (3.1) mm2, Cypher 1.0 (0.8) mm......2, BMS 0.9 (1.2) mm2; p = 0.30) was greatest in the AMS group. In a dichotomised IVUS assessment of vascular remodelling, six AMS stents were remodelled (negative remodelling: n = 5; positive remodelling: n = 1) at 90-day follow-up (AMS versus Cypher + BMS: p = 0.001). Neointima formation...

  17. From bare to covered: 15-year single center experience and follow-up in trans-catheter stent implantation for aortic coarctation.

    Science.gov (United States)

    Butera, Gianfranco; Manica, João Luiz Langer; Marini, Davide; Piazza, Luciane; Chessa, Massimo; Filho, Raul Ivo Rossi; Sarmento Leite, Rogério E; Carminati, Mario

    2014-05-01

    Bare stents has become the first line therapy for aortic coarctation. Covered stents has been reported more recently in clinical practice. The present study, reports comparatively 15-year experience of bare and covered stent implantation for aortic coarctation in a single tertiary referral center. From 1997 to 2011, 143 patients with native or postoperative aortic coarctation were treated at our institution. Seventy-one subjects (median age 17 years (range from 4 to 70 years) underwent bare stent implantation (Group 1) while 72 patients (median age of 17.5 years (range from 6 to 68 years) underwent covered stent implantation (Group 2). Success rate in the whole group was 95%. More complex and tighter coarctations were treated using covered stents. Incidence of related-procedure adverse events was higher in Group 1 than in group 2 (21.1% vs. 8.3% P = 0.035). Aortic wall complications occurred in 7% of patients in Group 1 (one death) and 0% in Group 2 (P = 0.028). Subjects in Group 1 had a longer follow-up (median 85 vs. 35 months; P 10 mm Hg (HR: 4.30; CI: 1.96-9.47). Both bare and covered stent implantation for aortic coarctation is a safe and efficacious treatment. By using covered stent implantation the spectrum of patients treated has increased with lower rates of acute and late complications. Copyright © 2014 Wiley Periodicals, Inc.

  18. Quality difference of neointima following the implantation of bioresorbable scaffold and metallic stent in patients with ST elevation myocardial infarction: quantitative assessments by light intensity, light attenuation, and backscatter on optical coherence tomography in TROFI II trial.

    Science.gov (United States)

    Sotomi, Yohei; Onuma, Yoshinobu; Liu, Shengnan; Asano, Taku; Eggermont, Jeroen; Katagiri, Yuki; Cavalcante, Rafael; de Winter, Robbert J; Wykrzykowska, Joanna J; Brugaletta, Salvatore; Räber, Lorenz; Sabaté, Manel; Windecker, Stephan; Dijkstra, Jouke; Serruys, Patrick W

    2018-02-27

    We aimed to assess possible difference of the neointimal quality after everolimus-eluting bioresorbable scaffold (BVS) implantation in comparison with cobalt chromium everolimus-eluting scaffold (CoCr-EES) by optical frequency domain imaging (OFDI). This study is a post-hoc analysis of TROFI II trial assessing neointimal quality 6-month after the implantation of BVS(N=82) and CoCr-EES(N=87) in STEMI patients. Neointimal light property analysis by OFDI full-automatically computed light attenuation, backscatter and light intensity for superficial and deep neointima. High light attenuation/backscatter and high light intensity are reportedly associated with lipidic change and tissue maturation, respectively. Superficial and deep neointima in BVS presented lower light attenuation than CoCr-EES (superficial:0.77±0.15 vs. 1.27±0.55mm-1, p<0.001; deep:0.88±0.20 vs. 1.17±0.27mm-1, p<0.001). Superficial neointima in BVS showed comparable backscatter to that of CoCr-EES (4.81±0.52 vs. 4.94±0.61, p=0.141), while deep neointima in BVS showed lower backscatter than that of CoCr-EES (4.60±0.62 vs. 4.97±0.62, p<0.001). Light intensity of superficial neointima was comparable between both arms (139±13 vs. 144±30, p=0.236), whereas light intensity of deep neointima in BVS was lower than CoCr-EES (129±14 vs. 138±21, p<0.001). The present OFDI comparison suggested that tissue maturation was comparable but lipidic change of neointima was less prominent after the BVS implantation than CoCr-EES.

  19. Ductal Stent Implantation in Tetralogy of Fallot with Aortic Arch Abnormality

    Science.gov (United States)

    Ergul, Yakup; Saygi, Murat; Ozyilmaz, Isa; Guzeltas, Alper; Odemis, Ender

    2015-01-01

    Stenting of patent ductus arteriosus is an alternative to palliative cardiac surgery in newborns with duct-dependent or decreased pulmonary circulation; however, the use of this technique in patients with an aortic arch abnormality presents a challenge. Tetralogy of Fallot is a congenital heart defect that is frequently associated with anomalies of the aortic arch and its branches. The association is even more common in patients with chromosome 22q11 deletion. We present the case of an 18-day-old male infant who had cyanosis and a heart murmur. After an initial echocardiographic evaluation, the patient was diagnosed with tetralogy of Fallot and right-sided aortic arch. The pulmonary annulus and the main pulmonary artery and its branches were slightly hypoplastic; the ductus arteriosus was small. Conventional and computed tomographic angiograms revealed a double aortic arch and an aberrant left subclavian artery. The right aortic arch branched into the subclavian arteries and continued into the descending aorta, whereas the left aortic arch branched into the common carotid arteries and ended with the patent ductus arteriosus. After evaluation of the ductal anatomy, we implanted a 3.5 × 15-mm coronary stent in the duct. Follow-up injections showed augmented pulmonary flow and an increase in oxygen saturation from 65% to 94%. The patient was also found to have chromosome 22q11 deletion. PMID:26175649

  20. [Pulmonary reperfusion syndrome after pulmonary stent implants in a patient with vascular tortuosity syndrome].

    Science.gov (United States)

    Berenguer Potenciano, M; Piris Borregas, S; Mendoza Soto, A; Velasco Bayon, J M; Caro Barri, A

    2015-01-01

    Vascular tortuosity syndrome is a rare genetic disorder that causes tortuosity and stenosis of the pulmonary, systemic and / or coronary circulations. As a result of treatment of pulmonary stenosis, symptoms of pulmonary edema, known as lung reperfusion syndrome, may occur. The case is presented of an adolescent patient with vascular tortuosity syndrome who presented with a pulmonary reperfusion syndrome after multiple stent implants in the left pulmonary artery. After the procedure, the patient immediately developed an acute pulmonary edema with severe clinical deterioration, which required assistance with extracorporeal membrane oxygenation for recovery. Copyright © 2014 Asociación Española de Pediatría. Published by Elsevier Espana. All rights reserved.

  1. Transcatheter double stent implantation for treatment of middle aortic coarctation syndrome.

    Science.gov (United States)

    McMahon, Colin J; Lambert, Imelda; Walsh, Kevin P

    2013-10-01

    A 13-year-old boy presented with severe systemic hypertension. His upper limb blood pressure measured 190/100 mm Hg and lower limb blood pressure measured 98/64 mm Hg. The brachial pulses were bounding and femoral pulses were not palpable. Echocardiography and magnetic resonance angiography confirmed middle aortic syndrome. There was severe diffuse thoraco-abdominal coarctation with continuous Doppler run-off. Cardiac catheterization was undertaken and using a retrograde approach two Advanta V12 stents were implanted in the complex thoraco-abdominal coarctation. The gradient across the coarctation was reduced from 80 to 40 mm Hg gradient with a significant improvement in the luminal diameter of the aorta. His upper limb blood pressure reduced to 142/78 mm Hg six weeks later. Copyright © 2013 Wiley Periodicals, Inc.

  2. Successful drug-eluting stent implantation in a male patient with dextrocardia: a case report

    Directory of Open Access Journals (Sweden)

    Long Wenjie

    2017-12-01

    Full Text Available Situs inversus with dextrocardia is a rare condition, with complete transposition of all the body organs, including the heart. Percutaneous coronary intervention (PCI in these patients is technically difficult because of the mirror image of organs. Here, we describe a 56-year-old man with coronary heart disease with known situs inversus with dextrocardia and coronary percutaneous intervention was performed for stenosis in the right coronary artery. A drug eluting stent was implanted at this site successfully. This case suggested that the interventional management of such patients follows the same general rules as for non-dextrocardia patients, but the manipulation of the catheter and projection position choices need to be taken into consideration to obtain optimal benefits for the patient.

  3. Assessment of the adequacy of bronchial stenting by flow-volume loops

    Energy Technology Data Exchange (ETDEWEB)

    McLaren, Clare A.; Roebuck, Derek J. [Great Ormond Street Hospital for Children, Department of Radiology, London (United Kingdom); Pigott, Nick; Elliott, Martin J. [Great Ormond Street Hospital for Children, Cardiothoracic Unit, London (United Kingdom); Dunne, Catherine [Great Ormond Street Hospital for Children, Department of Physiotherapy, London (United Kingdom)

    2006-08-15

    Airway compression is a common problem in children with certain forms of congenital heart disease. Although various surgical approaches are available to overcome this form of airway obstruction, internal stenting is necessary in a minority of patients. It can be difficult to assess the success of stenting at the time of the procedure, and the interval to successful extubation is usually used as an outcome measure. Measurement of relevant parameters of respiratory physiology with flow-volume and volume-pressure loops permits immediate quantitative assessment of the adequacy of stenting. A 3-month-old infant who underwent bronchial stenting and physiological assessment at the time of the procedure is described. (orig.)

  4. Assessment of the adequacy of bronchial stenting by flow-volume loops

    International Nuclear Information System (INIS)

    McLaren, Clare A.; Roebuck, Derek J.; Pigott, Nick; Elliott, Martin J.; Dunne, Catherine

    2006-01-01

    Airway compression is a common problem in children with certain forms of congenital heart disease. Although various surgical approaches are available to overcome this form of airway obstruction, internal stenting is necessary in a minority of patients. It can be difficult to assess the success of stenting at the time of the procedure, and the interval to successful extubation is usually used as an outcome measure. Measurement of relevant parameters of respiratory physiology with flow-volume and volume-pressure loops permits immediate quantitative assessment of the adequacy of stenting. A 3-month-old infant who underwent bronchial stenting and physiological assessment at the time of the procedure is described. (orig.)

  5. Implante de Stent guiado por ultrassom intracoronariano melhora desfechos: meta-análise de ensaios randomizados

    Directory of Open Access Journals (Sweden)

    Graciele Sbruzzi

    2012-01-01

    Full Text Available FUNDAMENTO: Ultrassom Intracoronariano (USIC tem sido usado como um método auxiliar a fim de otimizar o implante de stents. No entanto, o impacto desse método em alguns resultados é controverso. OBJETIVO: Analisar sistematicamente o impacto dos stents coronarianos guiados por USIC, em comparação com os stents guiados angiograficamente, sobre os resultados clínicos e angiográficos. MÉTODOS: Foi realizada uma busca em bases de dados (MEDLINE, Cochrane CENTRAL, EMBASE e referências de estudos publicados entre 1982 e 2010. Foram incluídos Ensaios Clínicos Randomizados (ECR que compararam o implante de stents coronarianos guiados por angiografia e USIC versus implante de stents coronarianos guiados apenas por angiografia (ANGIO. O seguimento mínimo foi de seis meses e os resultados avaliados foram eventos cardíacos adversos importantes (MACE, Revascularização da Lesão-alvo (RLA e reestenose angiográfica. Dois revisores extraíram os dados de forma independente. Razão de risco sumário e intervalos de confiança de 95% (CI foram calculados com modelos com efeitos aleatórios. A abordagem GRADE foi utilizada para determinar a qualidade geral de evidências para cada resultado. RESULTADOS: Dos 3.631 artigos identificados, oito ECR avaliando um total de 2.341 pacientes foram incluídos. Houve uma redução de 27% na reestenose angiográfica (95% IC: 3% -46% e uma redução de 38% em RLA (95% IC: 17% -53% em favor de USIC versus ANGIO. No entanto, os MACE não foram reduzidos por USIC (RR: 0,79; 95%CI: 0,61-1,03. Os dados MACE representam apenas 47% do tamanho ótimo de informações necessárias para detectar com segurança um efeito de tratamento plausível. CONCLUSÕES: Observamos que o implante de stent coronariano guiado por USIC oferece reduções significativas em RLA e reestenose angiográfica em comparação com implante de stent guiado por angiografia, porém não reduz casos de MACE.

  6. A simple approach to preserve keratinized mucosa around implants using a pre-fabricated implant-retained stent: a report of two cases

    Science.gov (United States)

    Park, Jung-Chul; Yang, Ki-Bin; Choi, Youna; Kim, Yong-Tae; Jung, Ui-Won; Kim, Chang-Sung; Cho, Kyoo-Sung; Chai, Jung-Kiu; Kim, Chong-Kwan

    2010-01-01

    Purpose There is no consensus regarding the relationship between the width of keratinized mucosa and the health of peri-implant tissues, but clinicians prefer to provide enough keratinized mucosa around dental implants for long-term implant maintenance. An apically positioned flap during second stage implant surgery is the chosen method of widening the keratinized zone in simple procedures. However, the routine suture techniques used with this method tend to apply tension over the provisional abutments and decrease pre-existing keratinized mucosa. To overcome this shortcoming, a pre-fabricated implant-retained stent was designed to apply vertical pressure on the labial flap and stabilize it in a bucco-apical direction to create a wide keratinized mucous zone. Methods During second stage implant surgery, an apically displaced, partial thickness flap with a lingualized incision was retracted. A pre-fabricated stent was clipped over the abutments after connecting to the provisional abutment. Vertical pressure was applied to displace the labial flap. No suture was required and the stent was removed after 10 days. Results A clinically relevant amount of keratinized mucosa was achieved around the dental implants. Buccally displaced keratinized mucosa was firmly attached to the underlying periosteum. A slight shrinkage of the keratinized zone was noted after the healing period in one patient, but no discomfort during oral hygiene was reported. Clinically healthy gingiva with enough keratinized mucosa was achieved in both patients. Conclusions The proposed technique is a simple and time-effective technique for preserving and providing keratinized tissue around dental implants PMID:20827329

  7. Thoracic Stent Graft Implantation for Aortic Coarctation with Patent Ductus Arteriosus via Retroperitoneal Iliac Approach in the Presence of Small Sized Femoral Artery

    Science.gov (United States)

    Korkmaz, Ozge; Beton, Osman; Goksel, Sabahattin; Kaya, Hakkı; Berkan, Ocal

    2016-01-01

    Endovascular stent graft implantation is a favorable method for complex aortic coarctation accompanied by patent ductus arteriosus. Herein, an 18-year-old woman with complex aortic coarctation and patent ductus arteriosus was successfully treated by endovascular thoracic stent graft via retroperitoneal approach. The reason for retroperitoneal iliac approach was small sized common femoral arteries which were not suitable for stent graft passage. This case is the first aortic coarctation plus patent ductus arteriosus case described in the literature which is treated by endovascular thoracic stent graft via retroperitoneal approach. PMID:27242935

  8. Inferior mesenteric artery as outflow vessel in endoleaks after abdominal aortic stent-graft implantation: 36-month follow-up CT study

    Energy Technology Data Exchange (ETDEWEB)

    Dorffner, R.; Mostbeck, G. [Dept. of Radiology, Hospital of the Brothers of St. John, Eisenstadt (Austria); Schoder, M.; Thurnher, S.; Lammer, J. [Dept. of Angiography and Interventional Radiology, Univ. of Vienna (Austria); Hoelzenbein, T. [Dept. of Vascular Surgery, Univ. of Vienna (Austria)

    2001-11-01

    The aim of this study was to determine the role of the inferior mesenteric artery (IMA) as an outflow vessel in endoleaks after abdominal aortic stent-graft implantation. Forty consecutive patients in whom abdominal aortic aneurysms (AAA) had been treated with stent-graft implantation were evaluated retrospectively. Spiral-CT examinations and angiographies up to 36 months after implantation were analyzed. In 29 (73%) of the 40 patients the IMA was perfused prior to implantation. In 5 (17%) of these 29 cases, the artery remained perfused after stent-graft insertion. In all 5 cases, endoleaks were detected; however, in none of these cases was the IMA the sole cause. In 3 of these 5 cases, angiography showed antegrade flow in the IMA. Implantation of extension stent grafts caused thrombosis of the aneurysmal sac and the IMA. There were no secondary endoleaks caused by the IMA at the 36-month follow-up examinations. The majority of IMAs which are patent prior to intervention occlude after successful stent-graft insertion. In cases with leaks and angiographically proven antegrade flow in the IMA, implantation of extension stent grafts is a therapeutic alternative to embolization. In this study, the IMA was not responsible for secondary endoleaks. (orig.)

  9. Inferior mesenteric artery as outflow vessel in endoleaks after abdominal aortic stent-graft implantation: 36-month follow-up CT study

    International Nuclear Information System (INIS)

    Dorffner, R.; Mostbeck, G.; Schoder, M.; Thurnher, S.; Lammer, J.; Hoelzenbein, T.

    2001-01-01

    The aim of this study was to determine the role of the inferior mesenteric artery (IMA) as an outflow vessel in endoleaks after abdominal aortic stent-graft implantation. Forty consecutive patients in whom abdominal aortic aneurysms (AAA) had been treated with stent-graft implantation were evaluated retrospectively. Spiral-CT examinations and angiographies up to 36 months after implantation were analyzed. In 29 (73%) of the 40 patients the IMA was perfused prior to implantation. In 5 (17%) of these 29 cases, the artery remained perfused after stent-graft insertion. In all 5 cases, endoleaks were detected; however, in none of these cases was the IMA the sole cause. In 3 of these 5 cases, angiography showed antegrade flow in the IMA. Implantation of extension stent grafts caused thrombosis of the aneurysmal sac and the IMA. There were no secondary endoleaks caused by the IMA at the 36-month follow-up examinations. The majority of IMAs which are patent prior to intervention occlude after successful stent-graft insertion. In cases with leaks and angiographically proven antegrade flow in the IMA, implantation of extension stent grafts is a therapeutic alternative to embolization. In this study, the IMA was not responsible for secondary endoleaks. (orig.)

  10. Restenosis in coronary bare metal stents. Importance of time to follow-up: a comparison of coronary angiograms 6 months and 4 years after implantation

    DEFF Research Database (Denmark)

    Jørgensen, Erik; Helqvist, Steffen; Kløvgaard, Lene

    2008-01-01

    Objectives. Angiographic late lumen loss measured 6 to 9 month after bare metal stent implantation in the coronary arteries is a validated restenosis parameter. Design. We performed a second angiographic follow-up after 4 years in event free survivors from the DANSTENT trial cohort. Results......-sectional vessel area and a 39% reduction of the binary restenosis rate over time. Conclusions. Instent late lumen loss in bare metal stents decreases spontaneously over time. Maturation of early hyperplastic tissue reaction after stent implantation with subsequent thinning of fibrotic tissue might explain...

  11. Comparison of Drug-Eluting Stent with Bare-Metal Stent Implantation in Femoropopliteal Artery Disease: A Systematic Review and Meta-Analysis.

    Science.gov (United States)

    Ding, Yong; Zhou, Min; Wang, Yonggang; Cai, Liang; Shi, Zhenyu

    2018-03-04

    This study aimed to perform a systematic review and meta-analysis of current evidence comparing the drug-eluting stent (DES) with the bare-metal stent (BMS) in the treatment of femoropopliteal artery disease (FPAD). All relevant articles reporting the results of DES versus BMS implantation in FPAD were systematically searched in MEDLINE, EMBASE, and Cochrane database. Randomized controlled trial, cohort, and retrospective study were all included. The efficacy endpoints included late lumen loss, binary restenosis, primary patency rate, freedom from target lesion revascularization, and stent fracture. Related data of the follow-up outcomes were extracted and pooled. For each endpoint, odds ratios (ORs) and 95% confidence intervals (CIs) were calculated. A total of 9 studies with 776 patients were included in this meta-analysis. There was no statistically significant difference between the DES and BMS groups in terms of late lumen loss at 6 months (SMD = -0.37, P = 0.07); binary restenosis at 6, 12, and 24 months (OR = 0.44, P = 0.20; OR = 0.75, P = 0.74; OR = 0.62, P = 0.36; respectively); primary patency rate at 6, 12, and 24 months (OR = 1.18, P = 0.73; OR = 1.43, P = 0.70; OR = 1.25, P = 0.68, respectively); freedom from target lesion revascularization at 12 months (OR = 1.13, P = 0.79); and stent fracture at 6 months (OR = 1.67, P = 0.38). A sensitivity analysis demonstrated that there was a significant benefit in the DES group over the BMS group in binary restenosis at 6 months (OR = 0.22, P = 0.008) after excluding a retrospective study, whereas no significant difference was observed when eliminating any other study. A subgroup analysis did not reveal any significant difference between a subgroup (sirolimus-eluting stent or paclitaxel-eluting stent) and the BMS group in FPAD. According to current evidence, DES was not superior to BMS in the treatment of FPAD. Further larger randomized controlled trials are needed to provide more evidence in the comparison

  12. Incidence of periprocedural myocardial infarction following stent implantation: Comparison between first- and second-generation drug-eluting stents

    NARCIS (Netherlands)

    Tandjung, Kenneth; Basalus, Mounir W.Z.; Muurman, Esther; Louwerenburg, Hans W.; van Houwelingen, Gert K.; Stoel, Martin G.; de Man, Frits H.A.F.; Jansen, Hanneke; Huisman, Jennifer; Linssen, Gerard C.M.; Droste, Herman T.; Nienhuis, Mark B.; von Birgelen, Clemens

    2012-01-01

    Background: First- and second-generation drug-eluting stents (DES) differ in coating materials, which may influence the incidence of periprocedural myocardial infarction (PMI). Objective: To compare the incidence of PMI between first- and second-generation DES, using the current Academic Research

  13. Augmentation of wall shear stress inhibits neointimal hyperplasia after stent implantation - Inhibition through reduction of inflammation?

    NARCIS (Netherlands)

    Carlier, SG; van Damme, LCA; Blommerde, CP; Wentzel, JJ; van Langehove, G; Verheye, S; Kockx, MM; Knaapen, MWM; Cheng, C; Gijsen, F; Duncker, DJ; Stergiopulos, N; Slager, CJ; Serruys, PW; Krams, R

    2003-01-01

    Background - Low wall shear stress (WSS) increases neointimal hyperplasia (NH) in vein grafts and stents. We studied the causal relationship between WSS and NH formation in stents by locally increasing WSS with a flow divider (Anti-Restenotic Diffuser, Endoart SA) placed in the center of the stent.

  14. Impact of Cigarette Smoking and Smoking Cessation on Stent Changes as Determined by Optical Coherence Tomography After Sirolimus Stent Implantation.

    Science.gov (United States)

    Huang, Xingtao; Wang, Xuedong; Zou, Yongpeng; Chen, Shuyuan; Zhang, Ruoxi; Li, Lulu; Yu, Bo; Hou, Jingbo

    2017-10-15

    There is debate regarding whether smoking results in microstructural changes after stenting. The aim of this study was to evaluate the microstructural changes after stenting in patients with different smoking statuses. We retrospectively identified 220 sirolimus-eluting stents in 179 patients who underwent follow-up optical coherence tomography examination 12 months after sirolimus stenting. Subjects were classified as current smokers (CS, n = 31), smoking cessation ≤1 year (n = 36), smoking cessation >1 year (SC > 1Y, n = 27), and never smokers (NS, n = 85). The neointimal hyperplasia (NIH) area was larger in CS than in NS (1.04 ± 0.72 mm 2 vs 0.96 ± 0.68 mm 2 ; p = 0.04). The incidence of lipid-laden neointima was lower in SC > 1Y patients (1.6%) than in all other patients (NS: 3.9%, p = 0.002; CS: 3.0%, p = 0.073; SC1Y: 5.0%, p Smoking cessation level was negatively correlated with NIH (B = -0.154; 95% confidential interval -0.187, -0.121; p smoking cessation patients showed a decreased trend in the incidence of malapposed struts (p = 0.0003). In conclusion, continued smoking increases NIH and the incidence of malapposed struts. However, smoking cessation slows down NIH progression and decreases the incidence of malapposed struts. Smoking cessation promotes vascular healing after stenting. Copyright © 2017. Published by Elsevier Inc.

  15. Multimodality Imaging of the Long-term Vascular Responses Following Implantation of Metallic and Bioresorbable Devices

    NARCIS (Netherlands)

    V.D. Gkogkas (Vasileios)

    2014-01-01

    markdownabstract__Abstract__ The pattern of vascular responses following stent/scaffold implantation in conventional interventional practice has been assessed by coronary angiography, intravascular ultrasound or optical coherence tomography and manifests as in-stent vascular response (focal or

  16. 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.

  17. Assessment of readability, quality and popularity of online information on ureteral stents.

    Science.gov (United States)

    Mozafarpour, Sarah; Norris, Briony; Borin, James; Eisner, Brian H

    2018-02-12

    To evaluate the quality and readability of online information on ureteral stents. Google.com was queried using the search terms "ureteric stent", "ureteral stent", "double J stent" and, "Kidney stent" derived from Google AdWords. Website popularity was determined using Google Rank and the Alexa tool. Website quality assessment was performed using the following criteria: Journal of the American Medical Association (JAMA) benchmarks, Health on the Net (HON) criteria, and a customized DISCERN questionnaire. The customized DISCERN questionnaire was developed by combining the short validated DISCERN questionnaire with additional stent-specific items including definition, placement, complications, limitations, removal and "when to seek help". Scores related to stent items were considered as the "stent score" (SS). Readability was evaluated using five readability tests. Thirty-two websites were included. The mean customized DISCERN score and "stent score" were 27.1 ± 7.1 (maximum possible score = 59) and 14.6 ± 3.8 (maximum possible score = 24), respectively. A minority of websites adequately addressed "stent removal" and "when to seek medical attention". Only two websites (6.3%) had HON certification (drugs.com, radiologyinfo.org) and only one website (3.3%) met all JAMA criteria (bradyurology.blogspot.com). Readability level was higher than the American Medical Association recommendation of sixth-grade level for more than 75% of the websites. There was no correlation between Google rank, Alexa rank, and the quality scores (P > 0.05). Among the 32 most popular websites on the topic of ureteral stents, online information was highly variable. The readability of many of the websites was far higher than standard recommendations and the online information was questionable in many cases. These findings suggest a need for improved online resources in order to better educate patients about ureteral stents and also should inform physicians that popular websites may

  18. Estudo comparativo randomizado do implante de Stent de aço inoxidável recoberto por carbono semelhante ao diamante versus não recoberto em pacientes com doença arterial coronariana Randomized comparative study of diamond-like carbon coated stainless steel stent versus uncoated stent implantation in patients with coronary artery disease

    Directory of Open Access Journals (Sweden)

    George César Ximenes Meireles

    2007-04-01

    Full Text Available OBJETIVO: Comparar as taxas de reestenose e de eventos cardíacos maiores em um e seis meses pós-implante de stents recobertos com CSD com os não-recobertos. MÉTODOS: Estudo comparativo, prospectivo, randomizado, de 180 pacientes com diagnóstico de insuficiência coronária, submetidos a implante de stent recoberto com CSD (Phytis® ou stent não-recobertos (Penta®, no período de janeiro de 2003 a julho de 2004. Foram critérios de inclusão: lesão de novo com porcentual de estenose em diâmetro > 50% em artéria coronária com diâmetro de referência > 2,5 mm e OBJECTIVE: To compare restenosis and major cardiac event rates at one and six months after DLC-coated stent implantation with those of uncoated stents. METHODS: Randomized, prospective, comparative study of 180 patients with coronary insufficiency undergoing DLC coated stent (Phytis™ or uncoated stent (Penta™ implantation, from January, 2003 to July, 2004. Inclusion criteria were: de novo lesion with >50% diameter stenosis in a coronary artery with reference diameter > 2,5 mm and < 4 mm, and length < 20 mm. Exclusion criteria were: left main coronary artery and bifurcation lesions, chronic total occlusion, and in-stent restenosis. RESULTS: Clinical and angiographic baseline characteristics of the groups were similar. Procedural success was achieved in 98.9% of the patients in both groups. One cardiac death occurred in each group during hospitalization. Reference diameter and acute gain were greater in the Penta™ group (3.21±0.37 mm vs. 3.34±0.8 mm, p=0.02 and 2.3±0.5 vs. 2.49±0.5, p=0.009, respectively. Angiographic follow-up at six months showed similar rates of restenosis (24.3% vs. 21.8%, p=0.84 and of major cardiac events (16.8% vs. 17.5%, p=1. CONCLUSION: DLC coated stents did not provide better outcomes in relation to uncoated stents.

  19. High frequency of contact allergy to gold in patients with endovascular coronary stents.

    Science.gov (United States)

    Ekqvist, S; Svedman, C; Möller, H; Kehler, M; Pripp, C M; Björk, J; Gruvberger, B; Holmström, E; Gustavsson, C G; Bruze, M

    2007-10-01

    Stent implantation is an effective method for treatment of atherosclerotic disease. Factors predisposing to in-stent restenosis are still largely unknown. Contact allergy to metal ions eluted from the stent has been suggested to be a risk factor. To explore whether there is a possible induction of contact allergy to metals used in stents among patients with a stainless steel stent containing nickel (Ni stent) and patients with a gold-plated stent (Au stent). Adults (n = 484) treated with coronary stent implantation participated in the study with patch testing. The study design was retrospective and cross-sectional with no assessment of contact allergy before stenting. Age- and sex-matched patch-tested patients with dermatitis (n = 447) served as controls. Of Au-stented patients, 54 of 146 (37%) were allergic to gold compared with 85 of 447 (19%) controls (P stented population there were no statistically significant differences in contact allergy to gold or nickel between Ni-stented and Au-stented patients. In multivariate models where other risk factors for contact allergy to gold were considered, the Au stent showed a trend towards statistical significance (odds ratio 1.43, 95% confidence interval 0.95-2.16; P = 0.09). As the frequency of contact allergy to gold is higher in stented patients independent of stent type it suggests a previous sensitization. However, several pieces of circumstantial evidence as well as statistical analysis indicate the possibility of sensitization in the coronary vessel by the Au stent. Ni stents and Au stents should not be ruled out as risk factors for induction of contact allergy to these metals.

  20. Assessment of Competence in EVAR Stent Graft Sizing and Selection

    DEFF Research Database (Denmark)

    Strøm, M; Lönn, L.; Bech, B.

    2017-01-01

    Objectives and background: The aims of this study were to develop a test of competence in endovascular aortic repair (EVAR) stent graft sizing and selection; to examine the test for evidence of validity; and to explore the experience required for the task. Methods: The test was developed based...... on a literature review resulting in 22 anatomical assessment points and a graft selection. Validity evidence was explored in an international cross sectional study. Twenty-two consultants with varying levels of experience in the field (novices, intermediates, and experts) were presented with computed tomography...... angiography of the aortic vessels from three patients. Test scores were based on summed z-scores using the anatomical measurements and graft choices of the experts as a reference. A proficiency score was established using the contrasting groups standard setting method. Results: The assessment was shown...

  1. Coronary stent implantation is superior to balloon angioplasty for chronic coronary occlusions: six-year clinical follow-up of the GISSOC trial.

    Science.gov (United States)

    Rubartelli, Paolo; Verna, Edoardo; Niccoli, Luigi; Giachero, Corinna; Zimarino, Marco; Bernardi, Guglielmo; Vassanelli, Corrado; Campolo, Luigi; Martuscelli, Eugenio

    2003-05-07

    We investigated whether the benefits of stent implantation over balloon percutaneous transluminal coronary angioplasty (PTCA) for treatment of chronic total coronary occlusions (CTO) are maintained in the long term. Several randomized trials have shown that in CTO, stent implantation confers clinical and angiographic mid-term outcomes superior to those observed after PTCA. However, limited information on the long-term results of either technique is available. Six-year clinical follow-up of patients enrolled in the Gruppo Italiano di Studio sullo Stent nelle Occlusioni Coronariche (GISSOC) trial was performed by direct visit or telephone interview. Major adverse cardiac events (MACE), defined as cardiac death, myocardial infarction, target lesion revascularization (TLR), and anginal status, were recorded. Freedom from MACE at six years was 76.1% in the stent group, compared with 60.4% in the PTCA group (p = 0.0555). This difference was due mainly to TLR-free survival rates (85.1% vs. 65.5% for the stent and PTCA groups, respectively; p = 0.0165). Eleven patients underwent TLR after the nine-month follow-up visit (stent group: n = 5; PTCA group: n = 6); however, in most cases, restenosis of the study occlusion was evident at nine-month angiography. This study represents the longest reported clinical follow-up of patients after percutaneous recanalization of CTO and demonstrates that the superiority of stent implantation over balloon PTCA is maintained in the long term. Stent and PTCA results appear to remain stable after nine-month angiographic follow-up. Stent implantation in CTO that can be recanalized percutaneously is therefore a valuable long-term therapeutic option.

  2. [Bentall operation combined with total arch replacement and stented elephant trunk implantation for serious Debakey I aortic dissecting aneurysm].

    Science.gov (United States)

    Gu, Tian-Xiang; Wang, Chun; Zhang, Yu-Hai

    2008-12-01

    To summarize the clinical experience of Bentall operation combined with total arch replacement and stented elephant trunk implantation for serious Debakey I aortic dissecting aneurysm. Twelve patients with serious Debakey I aortic dissecting aneurysm underwent surgical treatment from January 2005 to December 2007. There were 10 male and 2 female with the mean age of (40.1 +/- 9.5) years old. There were acute aortic dissection in 9 cases, chronic aortic dissection in 3 cases. The inner diameter of aorta was (5.3 +/- 1.8) cm. There were Marfan syndrome in 4 cases, aortic regurgitation in all cases, severely persistent chest pain in 9 cases, acute left heart failure in 8 cases, and cardiac tamponade in 4 cases. Bentall operations combined with total arch replacement and stented elephant trunk implantation were performed by using deep hypothermic circulatory arrest and antegrade selective cerebral perfusion in all cases. Urgent surgery underwent in 9 cases. The mean interval between the onset of aortic dissection and the accomplishment of surgery was (41.0 +/- 15.9) hours. Cardiopulmonary bypass time was (191 +/- 26) min, average cross clamp time was (134 +/- 31) min, and average deep hypothermic circulatory arrest time was (50.0 +/- 14.5) min. One patient died in hospital. The time stayed in ICU was 3 to 27 d. Mental disorder in 6 cases, hemi-paralysis in 1 case, amputation in 1 case, hemorrhage of anastomosis in 1 case, hemorrhage of alimentary tract in 1 case, and pleural effusion in 4 cases were recorded. Eleven cases were followed-up for 8 weeks to 36 months. There were no bending of the stents and no obstruction in the vascular prosthesis.No re-operation was needed. One case died 6 months postoperatively. Bentall operation combined with total arch replacement and stented elephant trunk implantation is safe and effective for serious Debakey I aortic dissecting aneurysm, while good organs protection and consummate cardiopulmonary bypass were taken.

  3. Metallic stent implantation in patients with iliac artery occlusion: long-term patency rate and factors related to recurrence

    International Nuclear Information System (INIS)

    Chung, Seok Kyun; Kim, Jae Kyu; Yoon, Woong; Kim, Jeong; Park, Jin Gyoon; Kang, Heoung Keun; Choi, Soo JinNa

    2003-01-01

    To determine the long-term patency rate in 68 patients with iliac artery occlusion who underwent metallic stent implantation, and to analyze the factors related to recurrence. Sixty-eight patients with occlusive disease of the iliac artery underwent implantation of a self-expandable metallic stent. The clinical symptoms were intermittent claudication (n=48), resting pain (n=11), and gangrene (n=9). Stent patency was determined by follow-up angiography and color Doppler imaging, and the cumulative patency rate using the Kaplan-Meier method. Cox's proportional hazard model was used to analyse recurrence-related factors involving clinical symptoms (Fontaine stage), risk factors, and anatomical factors such as lesion location, length, and the development of collaterals. The duration of follow-up varied from 1 day to 73 months (mean, 23.8 months). Arterial occlusion recurred in 16 of 68 patients (23.5%), and the cumulative patency rate was as follows: 95.4% at one month, 93.2% at six months, 80.1% at one year, 73.2% at two years, 68.9% at three years, and 62% at five years. According to a statistical analysis of risk factors, the recurrence (p=0.04) than in those without it, but in patients who smoked, hypertension, DM, and previous cerebrovascular disease were not statistically significant. With regard to anatomical factors, the recurrent rate for lesions involving the external iliac artery was 6.5 times higher (p=0.02) than for those involving the common iliac artery. Variations in the fontaine stage were not statistically significant indicators of recurrence. The recurrence rate after implantation of an iliac artery stent is higher in patients with heart disease than in those without it, and higher for occlusive lesions involving the external iliac artery than for those of the common iliac artery

  4. Failing left ventricle to ascending aorta conduit-Hybrid implantation of a melody valve and NuMed covered stent.

    Science.gov (United States)

    Gössl, Mario; Johnson, Jonathan N; Hagler, Donald J

    2014-04-01

    We present the case of a 36-year-old woman with increasing shortness of breath, a new 3/4 diastolic murmur, and a complex history of LV outflow tract obstruction. She has undergone multiple surgeries including the replacement of her old LV apex to ascending aorta conduit with a 20-mm Gore-Tex tube graft, addition of a 24-mm homograft sutured between the conduit and the LV apex, and insertion of a 21-mm Freestyle porcine valve conduit between the Gore-Tex tube graft and allograft at age 23. The current assessment showed a failing Freestyle conduit prosthesis leading to left heart decompensation. Due to substantial surgical risk, the patient underwent successful implantation of a Melody valve into the Gore-Tex tube and exclusion of the failing Freestyle bioprosthesis with a NuMed CP stent in a hybrid procedure. The case nicely illustrates the collaborative potential of cardiovascular surgeons and interventional cardiologists in the new arena of a hybrid operating room. Complex hybrid procedures like the current one, especially those including percutaneous placements of valves, offer therapeutic options for patients that are otherwise too high risk for conventional open heart surgery. Copyright © 2013 Wiley Periodicals, Inc.

  5. [Quality of life change and its influencing factors in patients with acute coronary syndrome after drug-eluting stent implantation].

    Science.gov (United States)

    Xue, Chao; Hu, Da-yi; Sun, Yi-hong; Ding, Rong-jing; Wang, Wei-min; Liu, Wen-ling; Li, Cui-lan; Li, Lei; Chen, Yu

    2012-04-01

    To prospectively evaluate the change of quality of life in patients with acute coronary syndrome following percutaneous coronary intervention (PCI) with drug-eluting stents and explore the influencing factors of quality of life. There hundred and thirty four consecutive patients with acute coronary syndrome receiving drug-eluting stents implantation between September 2008 and December 2009 were enrolled. Of them, two hundred and ninety three patients completed 36-item short form health survey at baseline and 6 months after PCI procedure. Change of quality of life and influencing factors on quality of life were analyzed. Compared with baseline, quality of life improved significantly after PCI in terms of both physical component summary and mental component summary [ (51.07 ± 20.39) scores vs. (61.69 ± 19.73) scores and (63.27 ± 20.00) scores vs. (68.81 ± 18.71) scores, respectively; all P Quality of life of acute coronary syndrome patients is significantly improved at 6 months after drug-eluting stents implantation. The predictors of physical quality of life improvement are female, diabetes, and ST-segment elevation myocardial infarction. Predictors of mental quality of life improvement are previous PCI and diabetes.

  6. The edge vascular response following implantation of the Absorb everolimus-eluting bioresorbable vascular scaffold and the XIENCE V metallic everolimus-eluting stent. First serial follow-up assessment at six months and two years: insights from the first-in-man ABSORB Cohort B and SPIRIT II trials.

    Science.gov (United States)

    Gogas, Bill D; Bourantas, Christos V; Garcia-Garcia, Hector M; Onuma, Yoshinobu; Muramatsu, Takashi; Farooq, Vasim; Diletti, Roberto; van Geuns, Robert-Jan M; De Bruyne, Bernard; Chevalier, Bernard; Thuesen, Leif; Smits, Pieter C; Dudek, Dariusz; Koolen, Jacques; Windecker, Stefan; Whitbourn, Robert; McClean, Dougal; Dorange, Cecile; Miquel-Hebert, Karine; Veldhof, Susan; Rapoza, Richard; Ormiston, John A; Serruys, Patrick W

    2013-10-01

    To assess serially the edge vascular response (EVR) of a bioresorbable vascular scaffold (BVS) compared to a metallic everolimus-eluting stent (EES). Non-serial evaluations of the Absorb BVS at one year have previously demonstrated proximal edge constrictive remodelling and distal edge changes in plaque composition with increase of the percent fibro-fatty (FF) tissue component. The 5 mm proximal and distal segments adjacent to the implanted devices were investigated serially with intravascular ultrasound (IVUS), post procedure, at six months and at two years, from the ABSORB Cohort B1 (n=45) and the SPIRIT II (n=113) trials. Twenty-two proximal and twenty-four distal edge segments were available for analysis in the ABSORB Cohort B1 trial. In the SPIRIT II trial, thirty-three proximal and forty-six distal edge segments were analysed. At the 5-mm proximal edge, the vessels treated with an Absorb BVS from post procedure to two years demonstrated a lumen loss (LL) of 6.68% (-17.33; 2.08) (p=0.027) with a trend toward plaque area increase of 7.55% (-4.68; 27.11) (p=0.06). At the 5-mm distal edge no major changes were evident at either time point. At the 5-mm proximal edge the vessels treated with a XIENCE V EES from post procedure to two years did not show any signs of LL, only plaque area decrease of 6.90% (-17.86; 4.23) (p=0.035). At the distal edge no major changes were evident with regard to either lumen area or vessel remodelling at the same time point. The IVUS-based serial evaluation of the EVR up to two years following implantation of a bioresorbable everolimus-eluting scaffold shows a statistically significant proximal edge LL; however, this finding did not seem to have any clinical implications in the serial assessment. The upcoming imaging follow-up of the Absorb BVS at three years is anticipated to provide further information regarding the vessel wall behaviour at the edges.

  7. Inflammatory markers in dependence on the plasma concentration of 37 fatty acids after the coronary stent implantation.

    Science.gov (United States)

    Handl, Jiří; Meloun, Milan; Mužáková, Vladimíra

    2018-02-05

    Using the regression model building the relationships between the concentration of 37 fatty acids of blood plasma phospholipids of 41 patients with coronary artery disease after coronary stent implantation, the inflammatory response and oxidative stress markers were estimated. The dynamics of the inflammatory response and the oxidative stress was indicated by measuring plasma concentrations of highly sensitive C-reactive protein, interleukin-6, serum amyloid A and malondialdehyde before, 24h after stent implantation. The multiple linear regression analysis was preceded by an exploratory data analysis, principal component analysis, factor analysis and cluster analysis, which proved a hidden internal relation of 37 fatty acids. The concentration of cerotic acid (C26:0) has been positively associated with an increase of malondialdehyde concentration after stent implantation, while the concentrations of tetracosatetraenoic (C24:4 N6) and nonadecanoic (C19:0) acids were associated with decrease of lipoperoxidation. The increase of interleukin-6 during the 24h after implantation was associated with higher levels of pentadecanoic acid (C15:0) and lower levels of α-linolenic acid (C18:3 N3). Regression models found several significant fatty acids at which the strength of the parameter β for each fatty acid on selected markers of C-reactive protein, malondialdehyde, interleukin-6 and serum amyloid A was estimated. Parameter β testifies to the power of the positive or negative relationship of the fatty acid concentration on the concentration of selected markers. The influencing effect of the cerotic acid (C26:0) concentration in plasma phospholipids exhibiting parameter β=140.4 is, for example, 3.5 times higher than this effect of n-3 tetracosapentaenoic acid (C24:5 N3) with β=40.0. Composition of fatty acids in plasma phospholipids shows spectrum of fatty acids available for intercellular communication in systemic inflammatory response of organism and should affect

  8. Effect of over-2-year dual antiplatelet therapy on the rate of major adverse cardiac and cerebral events for everolimus-eluting stent implantation: The landmark analysis from Tokyo-MD PCI registry.

    Science.gov (United States)

    Ueshima, Daisuke; Ashikaga, Takashi; Yoshikawa, Shunji; Sasaoka, Taro; Hatano, Yu; Kurihara, Ken; Maejima, Yasuhiro; Isobe, Mitsuaki

    2017-06-01

    Long-term dual antiplatelet therapy (DAPT) for patients treated with coronary stents has been reported to be effective. However the effectiveness of long-term DAPT for everolimus-eluting stent (EES) implanted patients has been controversial. We assessed the major adverse cardiac and cerebral events (MACCE: a composite of death, myocardial infarction, or cerebral arterial disease) in patients free from MACCE during the first 2 years after EES implantation. A total of 1918 patients who underwent successful percutaneous coronary intervention (PCI) with EES at 22 centers in Japan in 2010-2011 were enrolled, and 742 patients were free from MACCE for 2 years. We divided these MACCE-free patients into two groups: those who received DAPT for >2 years (Over-2-Year DAPT: n=591), and those who received DAPT for ≤2 years (Under-2-Year DAPT: n=151). We performed the landmark analysis that began at 2 years and evaluated at 3 years after PCI about the occurrence of MACCE, major bleeding, stent thrombosis, and restenosis between these groups, both with and without baseline adjustment by propensity score matching (n=145 in both groups). Fifty MACCE cases were reported (Over-2-Year DAPT, 38; Under-2-Year DAPT, 12), with no significant differences between the 2 groups (log-rank test, p=0.19). Even after baseline adjustment, there were no differences in MACCE occurrence (Over-2-Year DAPT, 8; Under-2-Year DAPT, 11, p=0.19); 15 cases of major bleeding, 5 of restenosis, and 2 of stent thrombosis were observed after 2-years' follow-up, with no statistical differences between the groups, although the event numbers were too low for comparison. Continuing DAPT for >2 years did not prevent MACCE in patients free from MACCE during initial 2 years after EES implantation. Few events of major bleeding, stent thrombosis, and restenosis were observed, with no statistical differences. Copyright © 2016 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.

  9. Regurgitant leak from the area between the stent post and the sewing ring of a stented bovine pericardial valve implanted in the aortic valve position.

    Science.gov (United States)

    Kuroda, Masataka; Sudo, Takashi; Koizuka, Shiro; Nishikawa, Koichi; Kadoi, Yuji; Saito, Shigeru

    2010-11-28

    Biologic valves can sometimes have a small closure or leakage backflow jet originating from the central coaptation point. This is physiologic regurgitation that usually only requires monitoring, and not treatment.Another non-central transvalvular leakage is occasionally seen in both porcine and pericardial valves and originates from the base of the stent post. Typically, it spontaneously decreases or even disappears by the end of the surgery, after administration of protamine. This leak, however, needs to be distinguished from abnormal paravalvular leakages, especially if the regurgitation is relatively large, as this may require an extra cardio-pulmonary bypass (CPB) run.In our case with stented bovine pericardial valves, detailed transesophageal echocardiography (TEE) examination immediately after CPB showed oblique and turbulent flow, which originated from the base of the stent post and flowed toward the anterior mitral leaflet. An extra CPB run, assessment of the cause of the leakage, and restoration if necessary, might have been required if the leakage did not improve or was exacerbated, because contact of the anterior mitral valve leaflet by the oblique flow is associated with the risks of infective endocarditis and hemolysis. Detailed TEE examination accurately delineated the site of the leak, which was subsequently found to originate from the site between the anterior stent post and the sewing ring. The leakage in this case was classified as non-paravalvular, non-central leakage within the sewing ring. Accurate diagnosis of the leakage by intra-operative TEE led to the decision to administer protamine and to adopt a wait-and-watch approach.

  10. Repair of an Atherosclerotic Coronary Artery Aneurysm by Implantation of a Coronary Covered Stent

    Directory of Open Access Journals (Sweden)

    Antenor Portela

    2002-05-01

    Full Text Available An atherosclerotic aneurysm of the right coronary artery complicated by a recent myocardial infarction was successfully treated with coronary artery stenting, using a device consisting of 2 stents with a layer of expandable polytetrafluorethylene (PTFE placed between them. A follow-up angiograph 5 months after the procedure showed sustained initial results.

  11. Repair of an Atherosclerotic Coronary Artery Aneurysm by Implantation of a Coronary Covered Stent

    OpenAIRE

    Portela, Antenor; Bastos, Raldir; Costa, Itamar; Paiva, Jayro

    2002-01-01

    An atherosclerotic aneurysm of the right coronary artery complicated by a recent myocardial infarction was successfully treated with coronary artery stenting, using a device consisting of 2 stents with a layer of expandable polytetrafluorethylene (PTFE) placed between them. A follow-up angiograph 5 months after the procedure showed sustained initial results.

  12. The application of self-expandable metalkic stent implantation under X-ray guidance by fibrobronchoscopy in treating malignant airway stenosis

    International Nuclear Information System (INIS)

    Zhou Xusheng; Zou Jianwei; Ni Caifang; Liu Yizhi; Feng Wei; Li Bo

    2010-01-01

    Objective: To evaluate the clinical effect of self-expandable metallic stent implantation under X-ray guidance by fibrobronchoscopy in treating malignant airway stenosis. Methods: Self-expandable metallic stent implantation under X-ray guidance by fibrobronchoscopy was performed in 34 patients with malignant airway stenosis. The dyspnea score was grade IV in 18 patients, grade III in 13 patients and grade II in 3 patients. The clinical data were retrospectively reviewed and analyzed. Results: A total of 36 stents were implanted successfully, of which 2 stents were partially covered. The dyspnea score decreased to grade 0 in 3 patients, to grade I in 26 patients and to grade II in 5 patients. No serious complications related to the procedure occurred. During the follow-up period ranged from 1 week to 6 years, restenosis developed in 5 patients, of which 2 died and clinical improvement was obtained in the remaining 3. In the remaining patients no dyspnea reocurred. Conclusion: As a simple and minimally-invasive technique, self-expandable metallic stent implantation under X-ray guidance by fibrobronchoscopy is a safe and effective treatment for malignant airway stenosis. (authors)

  13. Impact of stent size on angiographic and clinical outcomes after implantation of everolimus-eluting bioresorbable scaffolds in daily practice: insights from the ISAR-ABSORB registry.

    Science.gov (United States)

    Wiebe, Jens; Hoppmann, Petra; Kufner, Sebastian; Harada, Yukinori; Colleran, Roisin; Michel, Jonathan; Giacoppo, Daniele; Schneider, Simon; Cassese, Salvatore; Ibrahim, Tareq; Schunkert, Heribert; Laugwitz, Karl-Ludwig; Kastrati, Adnan; Byrne, Robert A

    2016-06-12

    We sought to evaluate the impact of stent size on angiographic and clinical outcomes after implantation of everolimus-eluting bioresorbable stents (BRS) in routine clinical practice. All consecutive patients undergoing BRS implantation at two centres in Munich, Germany, were included prospectively. The patient population was divided according to the diameter of the implanted BRS. Angiographic surveillance was scheduled at six to eight months after stent implantation and films were analysed in a core laboratory. A BRS with 2.5 mm diameter was implanted in 101 patients and BRS >2.5 mm diameter in 318. Baseline patient characteristics were similar in both groups. Reference vessel diameter was 2.36±0.22 mm in patients with an implanted 2.5 mm BRS and 3.03±0.40 mm in the other group (pstent late luminal loss (0.28±0.47 mm vs. 0.25±0.52 mm, p=0.74) was similar in both groups, though binary angiographic restenosis was numerically higher in patients treated with a 2.5 mm BRS (12.5% vs. 6.1%, p=0.05). After 12 months, the rate of the composite of death, myocardial infarction or target lesion revascularisation was 15.7% vs. 12.3% (p=0.49). Definite stent thrombosis was detected in 1.0% vs. 3.1% (p=0.31). In patients treated with BRS in routine clinical practice, angiographic and clinical outcomes were comparable in patients treated with a 2.5 mm stent as compared with those treated with a larger stent size.

  14. Two-year outcomes after first- or second-generation drug-eluting or bare-metal stent implantation in all-comer patients undergoing percutaneous coronary intervention: a pre-specified analysis from the PRODIGY study (PROlonging Dual Antiplatelet Treatment After Grading stent-induced Intimal hyperplasia studY).

    Science.gov (United States)

    Valgimigli, Marco; Tebaldi, Matteo; Borghesi, Marco; Vranckx, Pascal; Campo, Gianluca; Tumscitz, Carlo; Cangiano, Elisa; Minarelli, Monica; Scalone, Antonella; Cavazza, Caterina; Marchesini, Jlenia; Parrinello, Giovanni

    2014-01-01

    This study sought to assess device-specific outcomes after implantation of bare-metal stents (BMS), zotarolimus-eluting Endeavor Sprint stents (ZES-S), paclitaxel-eluting stents (PES), or everolimus-eluting stents (EES) (Medtronic Cardiovascular, Santa Rosa, California) in all-comer patients undergoing percutaneous coronary intervention. Few studies have directly compared second-generation drug-eluting stents with each other or with BMS. We randomized 2,013 patients to BMS, ZES-S, PES, or EES implantation. At 30 days, each stent group received up to 6 or 24 months of clopidogrel therapy. The key efficacy endpoint was the 2-year major adverse cardiac event (MACE) including any death, myocardial infarction, or target vessel revascularization, whereas the cumulative rate of definite or probable stent thrombosis (ST) was the key safety endpoint. Clinical follow-up at 2 years was complete for 99.7% of patients. The MACE rate was lowest in EES (19.2%; 95% confidence interval [CI]: 16.0 to 22.8), highest in BMS (32.1%; 95% CI: 28.1 to 36.3), and intermediate in PES (26.2%; 95% CI: 22.5 to 30.2) and ZES-S (27.8%; 95% CI: 24.1 to 31.9) groups (chi-square test = 18.9, p = 0.00029). The 2-year incidence of ST in the EES group (1%; 95% CI: 0.4 to 2.2) was similar to that in the ZES-S group (1.4%; 95% CI: 0.7 to 2.8), whereas it was lower compared with the PES (4.6%, 95% CI: 3.1 to 6.8) and BMS (3.6%; 95% CI: 2.4 to 5.6) groups (chi-square = 16.9; p = 0.0001). Our study shows that cumulative MACE rate, encompassing both safety and efficacy endpoints, was lowest for EES, highest for BMS, and intermediate for PES and ZES-S groups. EES outperformed BMS also with respect to the safety endpoints with regard to definite or probable and definite, probable, or possible ST. (PROlonging Dual antiplatelet treatment after Grading stent-induced Intimal hyperplasia studY [PRODIGY]; NCT00611286). Copyright © 2014 American College of Cardiology Foundation. Published by Elsevier Inc. All

  15. 2-year clinical outcomes after implantation of sirolimus-eluting, paclitaxel-eluting, and bare-metal coronary stents: results from the WDHR (Western Denmark Heart Registry)

    DEFF Research Database (Denmark)

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

    2009-01-01

    OBJECTIVES: This registry study assessed the safety and efficacy of the 2 types of drug-eluting stents (DES), sirolimus-eluting stents (SES) and paclitaxel-eluting stents (PES), compared with bare-metal stents (BMS). BACKGROUND: Drug-eluting stents may increase the risk of stent thrombosis (ST...... databases. We used Cox regression analysis to control for confounding. RESULTS: The 2-year incidence of definite ST was 0.64% in BMS patients, 0.79% in DES patients (adjusted relative risk [RR]: 1.09; 95% confidence interval [CI]: 0.72 to 1.65), 0.50% in SES patients (adjusted RR: 0.63, 95% CI: 0.35 to 1...

  16. Alterations in regional vascular geometry produced by theoretical stent implantation influence distributions of wall shear stress: analysis of a curved coronary artery using 3D computational fluid dynamics modeling

    Directory of Open Access Journals (Sweden)

    Warltier David C

    2006-06-01

    Full Text Available Abstract Background The success of stent implantation in the restoration of blood flow through areas of vascular narrowing is limited by restenosis. Several recent studies have suggested that the local geometric environment created by a deployed stent may influence regional blood flow characteristics and alter distributions of wall shear stress (WSS after implantation, thereby rendering specific areas of the vessel wall more susceptible to neointimal hyperplasia and restenosis. Stents are most frequently implanted in curved vessels such as the coronary arteries, but most computational studies examining blood flow patterns through stented vessels conducted to date use linear, cylindrical geometric models. It appears highly probable that restenosis occurring after stent implantation in curved arteries also occurs as a consequence of changes in fluid dynamics that are established immediately after stent implantation. Methods In the current investigation, we tested the hypothesis that acute changes in stent-induced regional geometry influence distributions of WSS using 3D coronary artery CFD models implanted with stents that either conformed to or caused straightening of the primary curvature of the left anterior descending coronary artery. WSS obtained at several intervals during the cardiac cycle, time averaged WSS, and WSS gradients were calculated using conventional techniques. Results Implantation of a stent that causes straightening, rather than conforms to the natural curvature of the artery causes a reduction in the radius of curvature and subsequent increase in the Dean number within the stented region. This straightening leads to modest skewing of the velocity profile at the inlet and outlet of the stented region where alterations in indices of WSS are most pronounced. For example, time-averaged WSS in the proximal portion of the stent ranged from 8.91 to 11.7 dynes/cm2 along the pericardial luminal surface and 4.26 to 4.88 dynes/cm2 along

  17. Placement of an implantable port catheter in the biliary stent: an experimental study in dogs

    International Nuclear Information System (INIS)

    Ko, Gi Young; Lee, Im Sick; Choi, Won Chan

    2004-01-01

    To investigate the feasibility of port catheter placement following a biliary stent placement. We employed 14 mongrel dogs as test subject and after the puncture of their gaIl bladders using sonographic guidance, a 10-mm in diameter metallic stent was placed at the common duct. In 12 dogs, a 6.3 F port catheter was placed into the duodenum through the common duct and a port was secured at the subcutaneous space following stent placement. As a control group, an 8.5 F drain tube was placed into the gallbladder without port catheter placement in the remaining two dogs. Irrigation of the bile duct was performed every week by injection of saline into the port, and the port catheter was replaced three weeks later in two dogs. Information relating to the success of the procedure, complications and the five-week follow-up cholangiographic findings were obtained. Placement of a biliary stent and a port catheter was technically successful in 13 (93%) dogs, while stent migration (n=3), gallbladder rupture (n=1) and death (n=5) due to subcutaneous abscess and peritonitis also occurred. The follow-up was achieved in eight dogs (seven dogs with a port catheter placement and one dog with a drain tube placement). Irrigation of the bile duct and port catheter replacement were successfully achieved without any complications. Cholangiograms obtained five weeks after stent placement showed diffuse biliary dilation with granulation tissue formation. However, focal biliary stricture was seen in one dog with stent placement alone. Placement of a port catheter following biliary stent placement seems to be feasible. However, further investigation is necessary to reduce the current complications

  18. Placement of an implantable port catheter in the biliary stent: an experimental study in dogs

    Energy Technology Data Exchange (ETDEWEB)

    Ko, Gi Young; Lee, Im Sick; Choi, Won Chan [Asan Medical Center, Seoul (Korea, Republic of)

    2004-04-01

    To investigate the feasibility of port catheter placement following a biliary stent placement. We employed 14 mongrel dogs as test subject and after the puncture of their gaIl bladders using sonographic guidance, a 10-mm in diameter metallic stent was placed at the common duct. In 12 dogs, a 6.3 F port catheter was placed into the duodenum through the common duct and a port was secured at the subcutaneous space following stent placement. As a control group, an 8.5 F drain tube was placed into the gallbladder without port catheter placement in the remaining two dogs. Irrigation of the bile duct was performed every week by injection of saline into the port, and the port catheter was replaced three weeks later in two dogs. Information relating to the success of the procedure, complications and the five-week follow-up cholangiographic findings were obtained. Placement of a biliary stent and a port catheter was technically successful in 13 (93%) dogs, while stent migration (n=3), gallbladder rupture (n=1) and death (n=5) due to subcutaneous abscess and peritonitis also occurred. The follow-up was achieved in eight dogs (seven dogs with a port catheter placement and one dog with a drain tube placement). Irrigation of the bile duct and port catheter replacement were successfully achieved without any complications. Cholangiograms obtained five weeks after stent placement showed diffuse biliary dilation with granulation tissue formation. However, focal biliary stricture was seen in one dog with stent placement alone. Placement of a port catheter following biliary stent placement seems to be feasible. However, further investigation is necessary to reduce the current complications.

  19. Safety and efficacy of coronary stent implantation. Acute and six month outcomes of 1,126 consecutive patients treated in 1996 and 1997

    Directory of Open Access Journals (Sweden)

    Luiz Alberto Mattos

    1999-07-01

    Full Text Available PURPOSE: The authors analyzed the 30-day and 6-month outcomes of 1,126 consecutive patients who underwent coronary stent implantation in 1996 and 1997. METHODS: The 30-day results and 6-month angiographic follow-up were analyzed in patients treated with coronary stents in 1996 and 1997. All patients underwent coronary stenting with high-pressure implantation (>12 atm and antiplatelet drug regimen (aspirin plus ticlopidine. RESULTS: During the study period, 1,390 coronary stents were implanted in 1,200 vessels of 1,126 patients; 477 patients were treated in the year 1996 and 649 in 1997. The number of percutaneous procedures performed using stents increased significantly in 1997 compared to 1996 (64 % vs 48%, p=0.0001. The 30-day results were similar in both years; the success and stent thrombosis rates were equal (97% and 0.8%, respectively. The occurrence of new Q wave MI (1.3% vs 1.1%, 1996 vs 1997, p=NS, emergency coronary bypass surgery (1% vs 0.6%, 1996 vs 1997, p=NS and 30-day death rates (0.2% vs 0.5%, 1996 vs 1997, p=NS were similar. The 6-month restenosis rate was 25% in 1996 and 27% in 1997 (p= NS; the target vessel revascularization rate was 15% in 1996 and 16% in 1997 (p = NS. CONCLUSIONS: Intracoronary stenting showed a high success rate and a low incidence of 30-day occurrence of new major coronary events in both periods, despite the greater angiographic complexity of the patients treated with in 1997. These adverse variables did not have a negative influence at the 6-month clinical and angiographic follow-up, with similar rates of restenosis and ischemia-driven target lesion revascularization rates.

  20. Cochlear implant assessment: imaging issues

    Energy Technology Data Exchange (ETDEWEB)

    Marsot-Dupuch, K. E-mail: kathlyn.marsot-dupuch@bct.ap-hop-paris.fr; Meyer, B

    2001-11-01

    Cochlear implants are electronic auditory prostheses used to rehabilitate deafened persons who have lost their hair cells. They are partly worn externally and partly implanted in the ear. They provide a direct stimulation of the spiral ganglion cells of the cochlear nerve by bypassing the destroyed hair cells. The objectives of this article are to summarise what head and neck surgeons need to know before cochlear implantation and to describe the imaging study protocol used and anomalies to look for. A few explanations are resumed about placement of a brainstem implant.

  1. Association of morphologic characteristics on optical coherence tomography and angiographic progression patterns of late restenosis after drug-eluting stent implantation

    Energy Technology Data Exchange (ETDEWEB)

    Yamaguchi, Hiroshi, E-mail: yhclinic@po5.synapse.ne.jp [Division of Cardiology, Tenyoukai Central Hospital, Izumi-cho, Kagoshima city, Kagoshima (Japan); Arikawa, Ryo; Takaoka, Junichiro; Miyamura, Akihiro; Atsuchi, Nobuhiko; Ninomiya, Toshiko; Atsuchi, Yoshihiko [Division of Cardiology, Tenyoukai Central Hospital, Izumi-cho, Kagoshima city, Kagoshima (Japan); Ohishi, Mitsuru [Department of Cardiovascular Medicine and Hypertension, Graduate School of Medical and Dental Science, Kagoshima University, Kagoshima (Japan); Terashima, Mitsuyasu [Department of Cardiology, Toyohashi Heart Center, Toyohashi (Japan); Kaneda, Hideaki [Okinaka Memorial Institute for Medical Research, Tokyo (Japan); Translational Research Informatics Center, Foundation for Biomedical Research and Innovation, Kobe (Japan)

    2015-01-15

    Objectives: To gain insight into the pathophysiology of late drug-eluting stent (DES) restenosis. Background: Restenosis of DES has a different time course from that of bare metal stents. Methods: Patients who underwent follow-up coronary angiography (CAG) twice (six to nine months and 18 to 24 months) after DES implantation were examined using optical coherence tomography (OCT). All lesions with target lesion revascularization at first follow-up were excluded. Late catch-up was defined as lesions that progressed from less than 50% diameter stenosis (DS) at the first CAG to more than 50% DS at the second CAG. Lesions with the late catch-up were further divided into two groups; lesions with jump-up (less than 25% DS at the first CAG) and lesions with gradual progression (25–50% DS at the first CAG). Results: Of the 25 patients who had late ISR, 23 patients (10 jump-up/13 gradual progression) were examined with OCT at late follow-up and enrolled in this study. In the qualitative OCT assessment, each ratio of homogeneous, layered, heterogeneous with or without attenuation tissue morphologies were in jump-up group, and gradual progression group were 0% and 15%, 0% and 23%, and 60% and 8%, and 40% and 54%, respectively. All of jump-up group showed heterogeneous restenotic tissue, while 62% of gradual progression group showed heterogeneous restenotic tissue (P = .04). Conclusions: These findings suggest different pathophysiology of the late catch-up after DES implantation between the jump-up and gradual progression groups.

  2. Persistent inhibition of neointimal hyperplasia after sirolimus-eluting stent implantation: long-term (up to 2 years) clinical, angiographic, and intravascular ultrasound follow-up

    NARCIS (Netherlands)

    M. Degertekin (Muzaffer); J.J. Popma (Jeffrey); K. Tanabe (Kengo); J. Vos (Jeroen); M.J.B.M. van den Brand (Marcel); P.J. de Feyter (Pim); P.W.J.C. Serruys (Patrick); D.P. Foley (David); W.J. van der Giessen (Wim); P.C. Smits (Pieter); E.S. Regar (Eveline)

    2002-01-01

    textabstractBACKGROUND: Early results of sirolimus-eluting stent implantation showed a nearly complete abolition of neointimal hyperplasia. The question remains, however, whether the early promising results will still be evident at long-term follow-up. The objective of our study was to evaluate the

  3. Hemodynamics in stented vertebral artery ostial stenosis based on computational fluid dynamics simulations.

    Science.gov (United States)

    Qiao, Aike; Dai, Xuan; Niu, Jing; Jiao, Liqun

    2016-01-01

    Hemodynamic factors may affect the potential occurrence of in-stent restenosis (ISR) after intervention procedure of vertebral artery ostial stenosis (VAOS). The purpose of the present study is to investigate the influence of stent protrusion length in implantation strategy on the local hemodynamics of the VAOS. CTA images of a 58-year-old female patient with posterior circulation transient ischemic attack were used to perform a 3D reconstruction of the vertebral artery. Five models of the vertebral artery before and after the stent implantation were established. Model 1 was without stent implantation, Model 2-5 was with stent protruding into the subclavian artery for 0, 1, 2, 3 mm, respectively. Computational fluid dynamics simulations based on finite element analysis were employed to mimic the blood flow in arteries and to assess hemodynamic conditions, particularly the blood flow velocity and wall shear stress (WSS). The WSS and the blood flow velocity at the vertebral artery ostium were reduced by 85.33 and 35.36% respectively after stents implantation. The phenomenon of helical flow disappeared. Hemodynamics comparison showed that stent struts that protruded 1 mm into the subclavian artery induced the least decrease in blood speed and WSS. The results suggest that stent implantation can improve the hemodynamics of VAOS, while stent struts that had protruded 1 mm into the subclavian artery would result in less thrombogenesis and neointimal hyperplasia and most likely decrease the risk of ISR.

  4. Comparison of clinical outcomes of coronary artery stent implantation in patients with end-stage chronic kidney disease including hemodialysis for three everolimus eluting (EES) stent designs: Bioresorbable polymer-EES, platinum chromium-EES, and cobalt chrome-EES.

    Science.gov (United States)

    Sato, Takao; Hatada, Katsuharu; Kishi, Syohei; Fuse, Koichi; Fujita, Satoshi; Ikeda, Yoshio; Takahashi, Minoru; Matsubara, Taku; Okabe, Masaaki; Aizawa, Yoshifusa

    2017-11-22

    New-generation bioresorbable polymer-everolimus eluting stents (BP-EES) are available. This study aimed to compare the clinical outcomes for BP-EES compared to more established stent designs, namely the platinum chromium-EES (PtCr-EES) and cobalt chrome-EES(CoCr-EES) in patients with the end-stage chronic kidney disease (CKD) including hemodialysis (HD). One-hundred-forty-one consecutive stents (BP-EES [n = 44], PtCr-EES [n = 45], and CoCr-EES [n = 52]) were implanted in 104 patients with CKD. All patients underwent a follow-up coronary angiography at 12 months after implantation. End-stage CKD was defined as an estimated glomerular filtration rate (eGFR) <30 mL/min/1.73 m 2 , or the need for HD. The following outcome variables were compared among the three stent groups after implantation and the 12-month follow-up: target lesion revascularization (TLR), stent thrombosis (ST), and major adverse cardiac event (MACE). Minimal stent diameter (MSD) and %diameter-stenosis (%DS) were measured using quantitative coronary angiography. The overall rate of TLR and MACE was 14.6% and 30.8%, respectively, with no incidence of ST. Immediately after implantation, the MSD (P = 0.22) and %DS (P = 0.42) were equivalent among the three groups. However, at the 12-month follow-up, a tendency towards higher TLR was observed for the BP-EES group (22.7%) compared with the PtCr-EES (8.8%) and CoCr-EES (9.6%) groups (P = 0.07). Late loss in lumen diameter was also significantly greater for the BP-EES (0.51 ± 0.64 mm) group than either the PtCr-EES (0.20 ± 0.61 mm) and CoCr-EES (0.25 ± 0.70 mm) groups (P = 0.03). BP-EES might increase the risk of in-stent restenosis in patients with end-stage of CKD or the need for HD. © 2017, Wiley Periodicals, Inc.

  5. Edge detection versus densitometry for assessing coronary stenting quantitatively

    NARCIS (Netherlands)

    B.H. Strauss (Bradley); Y. Juilliere; B.J.W.M. Rensing (Benno); J.H.C. Reiber (Johan); P.W.J.C. Serruys (Patrick)

    1991-01-01

    textabstractThe optimal method used to analyze quantitatively the immediate angiographic results of coronary stenting in the coronary arteries has not been studied. Accordingly, minimal luminal cross-sectional area was determined by 2 methods, edge detection and densitometry, in 19 patients who

  6. Quality assessment of pacemaker implantations in Denmark

    DEFF Research Database (Denmark)

    Møller, M; Arnsbo, P; Asklund, Mogens

    2002-01-01

    AIMS: Quality assessment of therapeutic procedures is essential to insure a cost-effective health care system. Pacemaker implantation is a common procedure with more than 500,000 implantations world-wide per year, but the general complication rate is not well described. We studied procedure relat...

  7. Serial intravascular ultrasound analysis of peri-stent remodeling and proximal and distal edge effects after sirolimus-eluting or paclitaxel-eluting stent implantation in patients with diabetes mellitus

    DEFF Research Database (Denmark)

    Jensen, Lisette Okkels; Maeng, Michael; Mintz, Gary S

    2009-01-01

    Patients with diabetes have an increased risk of in-stent restenosis after coronary stent implantation. Serial intravascular ultrasound was used to study chronic arterial responses and edge effects after implantation of Cypher (Cordis, Johnson & Johnson, Miami Lakes, Florida) or Taxus (Boston......-up. The increase in peri-stent external elastic membrane (EEM) volume was more pronounced in the Taxus group (292.4 +/- 132.6 to 309.5 +/- 146.8 mm(3)) than in the Cypher group (274.4 +/- 137.2 to 275.4 +/- 140.1 mm(3); p = 0.005). Peri-stent plaque volume increased in the Taxus group (152.5 +/- 73.7 to 166.......1 +/- 85.1 mm(3)), but was unchanged in the Cypher group (153.5 +/- 75.5 to 151.5 +/- 75.8 mm(3); p = 0.002). In proximal and distal reference segments, mean lumen area decreased within the entire 5-mm edge segment (proximal and distal) because of plaque progression (distal, 5.5 +/- 3.6 to 5.8 +/- 3.7 mm(2...

  8. Intraluminal Palmaz stent implantation. First clinical case report on a balloon-expandable vessel prosthesis

    Energy Technology Data Exchange (ETDEWEB)

    Palmaz, J.C.; Richter, G.M.; Noeldge, G.; Kauffmann, G.W.; Wenz, W.

    1987-12-01

    A 74-year-old patient suffering from severe iliac artery stenosis and claudication was chosen to be the first candidate in the world to receive the Palmaz stent, a balloon-expandable intraluminal stent. This procedure was done in the Department of Radiology, University of Freiburg, FRG. The intervention and postprocedural course were uneventful. His walking distance improved from less than 100 m to unlimited walking capacity. The intra-arterial pressure gradient and ankle-arm pressure ratio also returned to normal.

  9. Risk Associated With Surgery Within 12 Months After Coronary Drug-Eluting Stent Implantation

    DEFF Research Database (Denmark)

    Egholm, Gro; Dalby Kristensen, Steen; Thim, Troels

    2016-01-01

    BACKGROUND Guidelines recommend postponing surgery for at least 6 months after treatment with a drug-eluting stent by percutaneous coronary intervention (DES-PCI). OBJECTIVES The goal of this study was to evaluate the surgical risk associated with DES-PCI compared with that in nonstented patients...

  10. Characterization and mechanical investigation of Ti–O2−x film prepared by plasma immersion ion implantation and deposition for cardiovascular stents surface modification

    International Nuclear Information System (INIS)

    Xie Dong; Wan Guojiang; Maitz, Manfred F.; Lei Yifeng; Huang Nan; Sun Hong

    2012-01-01

    Highlights: ► We prepared Ti–O 2−x films of good quality by PIII and D successfully on stents product. ► The Ti–O 2−x film shows good homogeneity and intergradient film/substrate interface. ► The Ti–O 2−x films on stent sustain clinically-required expansion without failure. ► The films show good mechanical durability for cardiovascular stents application. - Abstract: Up to date, materials for cardiovascular stents are still far from satisfactory because of high risk of biomaterials-associated restenosis and thrombosis. Extensive efforts have been made to improve the biocompatibility of the materials by various surface modification techniques. Ti–O 2−x films prepared by plasma immersion ion implantation and deposition (PIII and D) have shown good blood compatibility. For clinical application, surface quality and mechanical durability of the Ti–O 2−x film on stents are also of critical importance for the long-term serving. In this paper we present our research results on surface quality, mechanical investigation and characterization of Ti–O 2−x films prepared using PIII and D on stent products provided by Boston Scientific SCIMED. Ti–O 2−x films with mostly Rutile and little non-stoichiometric phases were obtained with smoothness of 2−x films on stents products were sustained balloon-expansion of clinically-required extent without mechanical failure, showing highly potential feasibility for cardiovascular stents application.

  11. Characterization and mechanical investigation of Ti-O{sub 2-x} film prepared by plasma immersion ion implantation and deposition for cardiovascular stents surface modification

    Energy Technology Data Exchange (ETDEWEB)

    Xie Dong [Key Laboratory of Advanced Technologies of Materials, Ministry of Education, College of Materials Science and Engineering, Southwest Jiaotong University, Chengdu, 610031 (China); School of Physical Science and Technology, Southwest Jiaotong University, 610031 Chengdu (China); Wan Guojiang, E-mail: guojiang.wan@home.swjtu.edu.cn [Key Laboratory of Advanced Technologies of Materials, Ministry of Education, College of Materials Science and Engineering, Southwest Jiaotong University, Chengdu, 610031 (China); Maitz, Manfred F. [Key Laboratory of Advanced Technologies of Materials, Ministry of Education, College of Materials Science and Engineering, Southwest Jiaotong University, Chengdu, 610031 (China); Max Bergmann Center of Biomaterials Dresden, Leibniz Institute of Polymer Research Dresden, Dresden (Germany); Lei Yifeng; Huang Nan; Sun Hong [Key Laboratory of Advanced Technologies of Materials, Ministry of Education, College of Materials Science and Engineering, Southwest Jiaotong University, Chengdu, 610031 (China)

    2012-10-15

    Highlights: Black-Right-Pointing-Pointer We prepared Ti-O{sub 2-x} films of good quality by PIII and D successfully on stents product. Black-Right-Pointing-Pointer The Ti-O{sub 2-x} film shows good homogeneity and intergradient film/substrate interface. Black-Right-Pointing-Pointer The Ti-O{sub 2-x} films on stent sustain clinically-required expansion without failure. Black-Right-Pointing-Pointer The films show good mechanical durability for cardiovascular stents application. - Abstract: Up to date, materials for cardiovascular stents are still far from satisfactory because of high risk of biomaterials-associated restenosis and thrombosis. Extensive efforts have been made to improve the biocompatibility of the materials by various surface modification techniques. Ti-O{sub 2-x} films prepared by plasma immersion ion implantation and deposition (PIII and D) have shown good blood compatibility. For clinical application, surface quality and mechanical durability of the Ti-O{sub 2-x} film on stents are also of critical importance for the long-term serving. In this paper we present our research results on surface quality, mechanical investigation and characterization of Ti-O{sub 2-x} films prepared using PIII and D on stent products provided by Boston Scientific SCIMED. Ti-O{sub 2-x} films with mostly Rutile and little non-stoichiometric phases were obtained with smoothness of <3 nm RMS, largely homogeneity as well as good intergradient film/substrate interface. The Ti-O{sub 2-x} films on stents products were sustained balloon-expansion of clinically-required extent without mechanical failure, showing highly potential feasibility for cardiovascular stents application.

  12. Fatigue Assessment of Nickel-Titanium Peripheral Stents: Comparison of Multi-Axial Fatigue Models

    Science.gov (United States)

    Allegretti, Dario; Berti, Francesca; Migliavacca, Francesco; Pennati, Giancarlo; Petrini, Lorenza

    2018-02-01

    Peripheral Nickel-Titanium (NiTi) stents exploit super-elasticity to treat femoropopliteal artery atherosclerosis. The stent is subject to cyclic loads, which may lead to fatigue fracture and treatment failure. The complexity of the loading conditions and device geometry, coupled with the nonlinear material behavior, may induce multi-axial and non-proportional deformation. Finite element analysis can assess the fatigue risk, by comparing the device state of stress with the material fatigue limit. The most suitable fatigue model is not fully understood for NiTi devices, due to its complex thermo-mechanical behavior. This paper assesses the fatigue behavior of NiTi stents through computational models and experimental validation. Four different strain-based models are considered: the von Mises criterion and three critical plane models (Fatemi-Socie, Brown-Miller, and Smith-Watson-Topper models). Two stents, made of the same material with different cell geometries are manufactured, and their fatigue behavior is experimentally characterized. The comparison between experimental and numerical results highlights an overestimation of the failure risk by the von Mises criterion. On the contrary, the selected critical plane models, even if based on different damage mechanisms, give a better fatigue life estimation. Further investigations on crack propagation mechanisms of NiTi stents are required to properly select the most reliable fatigue model.

  13. Outcome After Long-segment Stenting With Everolimus-eluting Bioresorbable Scaffolds Focusing on the Concept of Overlapping Implantation.

    Science.gov (United States)

    Wiebe, Jens; Dörr, Oliver; Liebetrau, Christoph; Bauer, Timm; Wilkens, Eva; Ilstad, Hanna; Boeder, Niklas; Elsässer, Albrecht; Möllmann, Helge; Hamm, Christian W; Nef, Holger M

    2016-12-01

    The implantation of bioresorbable scaffolds (BRS) is an emerging technique used in percutaneous coronary interventions. Their application has been extended to more complex lesions, although evidence is only available for simple lesions. The present study evaluated scaffold implantation in long lesions, focusing on overlapping scaffolds. We retrospectively analyzed all consecutive patients eligible for stenting with everolimus-eluting poly-L-lactic acid-based BRS with a minimum total scaffold length of 28mm, irrespective of the number of BRS used. The main target parameters were major adverse cardiac events, comprising cardiac death, any myocardial infarction, and target lesion revascularization, and target lesion failure, including cardiac death, target vessel myocardial infarction, and target lesion revascularization. A subgroup analysis included patients with overlapping BRS. A total of 250 patients were included. The reason for angiography was stable coronary artery disease in 36.4% (91 of 250), an acute coronary syndrome in 61.6% (154 of 250), and other reasons in 2.0% (5 of 250). Procedural success was achieved in 97.8% (267 of 273) of the lesions. During follow-up, the 12-month rates of major adverse cardiac event, target lesion failure, and scaffold thrombosis were 8.5%, 6.6%, and 2.3%, respectively. Subgroup analysis of 239 patients showed that there were no statistically relevant differences between patients with and without overlapping scaffolds after a 12-month follow-up. Long-segment stenting with a single scaffold or with multiple overlapping scaffolds is technically feasible with adequate mid-term outcomes. However, large-scale randomized studies are needed to provide further proof of concept. Copyright © 2016 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.

  14. Final five-year outcomes after implantation of biodegradable polymer-coated biolimus-eluting stents versus durable polymer-coated sirolimus-eluting stents

    DEFF Research Database (Denmark)

    Jakobsen, Lars; Christiansen, Evald H; Maeng, Michael

    2017-01-01

    AIMS: Our aim was to report the long-term safety and efficacy of the biodegradable polymer-coated biolimus- eluting Nobori stent compared to the durable polymer-coated sirolimus-eluting CYPHER stent. METHODS AND RESULTS: SORT OUT V randomised 2,468 patients 1:1 to the Nobori (n=1,229) versus...... also found to be similar in patients treated with the two study stents (Nobori 23/1,229 [1.9%] vs. CYPHER 18/1,239 [1.5%]; OR 1.31, 95% CI: 0.70-2.47; p=0.40), as were the other secondary endpoints. CONCLUSIONS: At five-year follow-up, the Nobori stent with a biodegradable polymer coating provided...... a similar safety and efficacy profile when compared to the durable polymer first-generation CYPHER stent....

  15. Intravascular ultrasound guidance improves clinical outcomes during implantation of both first- and second-generation drug-eluting stents: a meta-analysis.

    Science.gov (United States)

    Nerlekar, Nitesh; Cheshire, Caitlin J; Verma, Kunal P; Ihdayhid, Abdul-Rahman; McCormick, Liam M; Cameron, James D; Bennett, Martin R; Malaiapan, Yuvaraj; Meredith, Ian T; Brown, Adam J

    2017-01-20

    Our aim was to assess whether intravascular ultrasound (IVUS) improves clinical outcomes during implantation of first- and second-generation drug-eluting stents (DES). IVUS guidance is associated with improved clinical outcomes during DES implantation, but it is unknown whether this benefit is limited to either first- or second-generation devices. MEDLINE, EMBASE and PubMed were searched for studies comparing outcomes between IVUS- and angiography-guided PCI. Among 909 potentially relevant studies, 15 trials met the inclusion criteria. The primary endpoint was MACE, defined as death, myocardial infarction, target vessel/lesion revascularisation (TVR/TLR) or stent thrombosis (ST). Summary estimates were obtained using Peto modelling. In total, 9,313 patients from six randomised trials and nine observational studies were included. First-generation DES were implanted in 6,156 patients (3,064 IVUS-guided and 3,092 angiography-guided) and second-generation in 3,157 patients (1,528 IVUS-guided and 1,629 angiography-guided). IVUS guidance was associated with a significant reduction in MACE (odds ratio [OR] 0.73, 95% CI: 0.64-0.85, pDES (0.57, 95% CI: 0.43-0.77, pDES, IVUS guidance was associated with significantly lower rates of cardiac death (OR 0.33, 95% CI: 0.14-0.78, p=0.02), TVR (OR 0.47, 95% CI: 0.28-0.79, p=0.006), TLR (OR 0.61, 95% CI: 0.42-0.90, p=0.01) and ST (OR 0.31, 95% CI: 0.12-0.78, p=0.02). Cumulative meta-analysis highlighted progressive temporal benefit towards IVUS-guided PCI to reduce MACE (OR 0.60, 95% CI: 0.48-0.75, pDES platforms. These data support the use of IVUS guidance in contemporary revascularisation procedures using second-generation DES.

  16. 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

  17. Langzeit-implantierte Aorten-Stent-Grafts : Morphologie der Implantations- und Komplikationsmuster

    OpenAIRE

    Ick, Thorben Jannes

    2008-01-01

    Problem: Die endovaskuläre Aortenstentimplantation zeigt gegenüber der offenen Chirurgie eine höhere Rate an Spätkomplikationen. Die Analyse der Komplikationsmuster langzeitimplantierter Stents soll zur Klärung ihrer Pathogenese beitragen. Methode: Es wurden 10 Aortenstentresektate (Zenit, Stentor, Talent, Vanguard) auf komplikative und dynamische Veränderungen makroskopisch, radiographisch, mikroskopisch, immunhistochemisch sowie rasterelektronenmikroskopisch untersucht. Die M...

  18. Comparison of vascular response after sirolimus-eluting stent implantation between patients with unstable and stable angina pectoris: a serial optical coherence tomography study.

    Science.gov (United States)

    Kubo, Takashi; Imanishi, Toshio; Kitabata, Hironori; Kuroi, Akio; Ueno, Satoshi; Yamano, Takashi; Tanimoto, Takashi; Matsuo, Yoshiki; Masho, Takashi; Takarada, Shigeho; Tanaka, Atsushi; Nakamura, Nobuo; Mizukoshi, Masato; Tomobuchi, Yoshiaki; Akasaka, Takashi

    2008-07-01

    The aim of the present study was to compare lesion morphologies after sirolimus-eluting stent (SES) implantation between patients with unstable angina pectoris (UAP) and stable angina pectoris (SAP) with the use of optical coherence tomography (OCT). The lesion morphologies before and after coronary stenting have been proposed as important predictors of clinical outcome. The high resolution of OCT provides detailed information of coronary vessel wall. We enrolled 55 patients (UAP: n = 24, SAP: n = 31), and examined lesion morphologies by using OCT at pre- and post-SES implantation and 9 months' follow-up. The incidence of plaque rupture (42% vs. 3%, p < 0.001), intracoronary thrombus (67% vs. 3%, p < or = 0.001) and thin-capped fibroatheroma (cap thickness <65 microm; 46% vs. 3%, p < 0.001) at pre-intervention was significantly greater in UAP than that in SAP. Although stent profiles and procedural characteristics were not different between the 2 groups, inadequate stent apposition (67% vs. 32%, p = 0.038) and tissue protrusion (79% vs. 42%, p = 0.005) after percutaneous coronary intervention were observed more frequently in patients with UAP. Plaque rupture was significantly increased after percutaneous coronary intervention in patients with UAP (42% to 75%, p = 0.018), and the persistence of core cavity after plaque rupture (28% vs. 4%, p = 0.031) at 9 months' follow-up was observed more frequently in UAP patients compared with SAP patients. At 9 months' follow-up, the incidence of inadequately apposed stent (33% vs. 4%, p = 0.012) and partially uncovered stent by neointima (72% vs. 37%, p = 0.019) was significantly greater in UAP patients than that in SAP patients. All patients took aspirin and ticlopidine during follow-up period, and no patients had stent thrombosis or adverse coronary events. Serial OCT examinations demonstrated markedly different vascular response up to 9 months after SES implantation between UAP and SAP patients. Although the inadequate

  19. Intra- and interobserver reliability and intra-catheter reproducibility using frequency domain optical coherence tomography for the evaluation of morphometric stent parameters and qualitative assessment of stent strut coverage

    International Nuclear Information System (INIS)

    Antonsen, Lisbeth; Thayssen, Per; Junker, Anders; Veien, Karsten Tange; Hansen, Henrik Steen; Hansen, Knud Nørregaard; Hougaard, Mikkel; Jensen, Lisette Okkels

    2015-01-01

    Purpose: Frequency-domain optical coherence tomography (FD-OCT) is a high-resolution imaging tool (~ 10–15 μm), which enables near-histological in-vivo images of the coronary vessel wall. The use of the technique is increasing, both for research- and clinical purposes. This study sought to investigate the intra- and interobserver reliability, as well as the intra-catheter reproducibility of quantitative FD-OCT-assessment of morphometric stent parameters and qualitative FD-OCT-evaluation of strut coverage in 10 randomly selected 6-month follow-up Nobori® biolimus-eluting stents (N-BESs). Methods: Ten N-BESs (213 cross sectional areas (CSAs) and 1897 struts) imaged with OCT 6 months post-implantation were randomly selected and analyzed by 2 experienced analysts, and the same 10 N-BESs were analyzed by one of the analysts 3 months later. Further, 2 consecutive pullbacks randomly performed in another 10 N-BESs (219 CSAs and 1860 struts) were independently assessed by one of the analysts. Results: The intraobserver variability with regard to relative difference of mean luminal area and mean stent area at the CSA-level was very low: 0.1% ± 1.4% and 0.5% ± 3.2%. Interobserver variability also proved to be low: − 2.1% ± 3.3% and 2.1% ± 4.6%, and moreover, very restricted intra-catheter variation was observed: 0.02% ± 6.8% and − 0.18% ± 5.2%. The intraobserver-, interobserver- and intra-catheter reliability for the qualitative evaluation of strut coverage was found to be: kappa (κ) = 0.91 (95% confidence interval (CI): 0.88–0.93, p < 0.01), κ = 0.88 (95% CI: 0.85–0.91, p < 0.01), and κ = 0.73 (95% CI: 0.68–0.78, p < 0.01), respectively. Conclusions: FD-OCT is a reproducible and reliable imaging tool for quantitative evaluation of stented coronary segments, and for qualitative assessment of strut coverage. - Highlights: • Frequency-domain optical coherence tomography (FD-OCT) is increasingly adopted in the catherization laboratories. • This

  20. Overcoming the delivery limitation: results of an approach to implanting an integrated self-expanding Y-shaped metallic stent in the carina.

    Science.gov (United States)

    Han, Xin-Wei; Wu, Gang; Li, Yong-Dong; Zhang, Qing-Xian; Guan, Sheng; Ma, Nan; Ma, Ji

    2008-05-01

    To evaluate the technical success and initial clinical safety and effectiveness of the use of a Y-shaped metallic stent for complex stenoses involving the carina. Thirty-five consecutive patients with complex tracheobronchial stenoses involving the carina were treated with an integrated self-expandable inverted Y-shaped metallic stent and delivery system. The Y-shaped metallic stents were placed in the tracheobronchial tree with fluoroscopic guidance. Technical success, clinical success, Hugh-Jones classification, and complications were assessed during follow-up. The delivery of the integrated self-expandable Y-shaped metallic stent in the carinal areas was technically successful and well-tolerated in all patients. Clinical success was achieved in 31 patients (89%) 1-7 days after stent placement; the procedure failed in four patients (11%). The improvement between pre- and postoperative Hugh-Jones classification grade was statistically significant (Preport. The mean and median survival periods were 217 days+/-30 and 215 days+/-108, respectively. The mean and median stent patency periods were 216 days+/-30 and 215 days+/-119, respectively. Deployment of an integrated, self-expandable inverted Y-shaped metallic stent with the delivery system was a safe and effective procedure for the treatment of complex tracheobronchial stenoses involving the carina.

  1. OCT guidance during stent implantation in primary PCI: A randomized multicenter study with nine months of optical coherence tomography follow-up.

    Science.gov (United States)

    Kala, Petr; Cervinka, Pavel; Jakl, Martin; Kanovsky, Jan; Kupec, Andrej; Spacek, Radim; Kvasnak, Martin; Poloczek, Martin; Cervinkova, Michaela; Bezerra, Hiram; Valenta, Zdenek; Attizzani, Guilherme F; Schnell, Audrey; Hong, Lu; Costa, Marco A

    2018-01-01

    To assess the possible merits of optical coherence tomography (OCT) guidance in primary percutaneous coronary intervention (pPCI). 201 patients with ST-elevation myocardial infarction (STEMI) were enrolled in this study. Patients were randomized either to pPCI alone (angio-guided group, n=96) or to pPCI with OCT guidance (OCT-guided group, n=105) and also either to biolimus A9 or to everolimus-eluting stent implantation. All patients were scheduled for nine months of follow-up angiography and OCT study. OCT guidance led to post-pPCI optimization in 29% of cases (59% malapposition and 41% dissections). No complications were found related to the OCT study. OCT analysis at nine months showed significantly less in-segment area of stenosis (6% [-11, 19] versus 18% [3, 33]; p=0.0002) in favor of the OCT-guided group. The rate major adverse cardiovascular events were comparable at nine months in both groups (3% in the OCT group versus 2% in the angio-guided group; p=0.87). This study demonstrates the safety of OCT guidance during pPCI. The use of OCT optimized stent deployment in 1/3 of patients in this clinical scenario and significantly reduced in-segment area of stenosis at nine months of follow-up. Whether such improvements in OCT endpoints will have a positive impact on late clinical outcomes, they demand both a larger and longer-term follow-up study. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Stent implantation for a totally occluded right coronary artery in a six-year-old boy after Kawasaki disease: a case report

    Directory of Open Access Journals (Sweden)

    Hsu Ya-Chi

    2012-04-01

    Full Text Available Abstract Introduction Coronary stenting has previously been considered to be less feasible in children under 12 years old due to the limitation of vascular access. We report the case of a six-year-old boy who successfully underwent stent implantation for his totally occluded right coronary artery. Case presentation A Taiwanese boy aged six years and nine months old was found to have giant aneurysms after an acute episode of Kawasaki disease. An angiography revealed that his middle right coronary artery was totally occluded. A 0.014-inch guidewire was advanced to cross the totally occluded site. After pre-dilating the middle portion of his right coronary artery with a 1.5 mm balloon, stenting of his right coronary artery was accomplished using a 2.5 × 28 mm and a 2.5 × 18 mm bare metal stent. A final angiography demonstrated no residual stenosis or dissection. Conclusion Coronary stenting could be a therapeutic option for children as young as six years old. Close follow-up is mandatory because the long-term outcome is still unclear, especially in a small child.

  3. Usefulness of multiplanar reformatted images of multi-detector row helical CT in assessment of biliary stent patency

    International Nuclear Information System (INIS)

    Kim, Soo Jin; Kim, Suk; Kim, Chang Won; Lee, Jun Woo; Lee, Tae Hong; Choo, Ki Seok; Koo, Young Baek; Moon, Tae Yong; Lee, Suk Hong

    2004-01-01

    To evaluate the usefulness of multi-detector row helical CT (MDCT), multiplanar reformatted images for the noninvasive assessment of biliary stent patency, and for the planning for management in patients with a sele-expandable metallic stent due to malignant biliary obstruction. Among 90 consecutive patients, from August 1999 to July 2003, 26 cases in 23 patients with malignant biliary obstruction who underwent self-expandable metaIlic stent insertion in the biliary system and percutaneous transhepatic biliary drainage within 7 days after CT were enrolled in this study. On CT images, the complete and functional obstruction of the stent and the precise level of obstruction were evaluated. The presence of an enhancing intraluminal mass or wall thickening around stent was determined, and the causes of obstruction were evaluated. These findings were then compared with percutaneous transhepatic cholangiography. Multi-detector row helical CT correctly demonstrated the patency of a stent in 24 cases (92.3%). It was adequate in helping to depict the precise level of stent occlusion in 23 cases (88.5%). Multi-detector row helical CT also revealed the extent of tumor that represented as an enhancing intraluminal mass or wall thickening around the stent in 23 cases, and this was represented as complete obstruction on percutaneous transhepatic cholangiography. In the case of functional obstruction, MDCT predicted the possible cause of the obstruction. Multiplanar reformatted images of multi-detector row helical CT is a useful imaging modality for the noninvasive assessment of stent patency and the precise level of obstruction when stent obstruction is suspected in the patients with self-expandable metallic stent due to malignant biliary obstruction. It can also predict the possible cause of the obstruction and allows adequate planning for the medical management of such cases

  4. Comparison of immediate results and follow-up of patients with single-vessel and multivessel coronary artery disease younger than 50 years of age undergoing coronary stent implantation

    Directory of Open Access Journals (Sweden)

    Anello Alexandre L.

    2003-01-01

    Full Text Available OBJECTIVE: To assess the in-hospital results and clinical follow-up of young patients (< 50 years with multivessel coronary artery disease undergoing stent implantation in native coronary arteries and to compare their results with those of patients with single-vessel coronary artery disease. METHODS: We retrospectively studied 462 patients undergoing coronary stent implantation. Patients were divided into 2 groups: group I (G-I - 388 (84% patients with single-vessel coronary artery disease; and group II (G-II - 74 (16% patients with multivessel coronary artery disease. RESULTS: The mean age of the patients was 45±4.9 years, and the clinical findings at presentation and demographic data were similar in both groups. The rate of clinical success was 95% in G-I and 95.8% in G-II (P=0.96, with no difference in regard to in-hospital evolution between the groups. Death, acute myocardial infarction, and the need for myocardial revascularization during clinical follow-up occurred in 10.1% and 11.2% (P=0.92 in G-I and G-II, respectively. By the end of 24 months, the actuarial analysis showed an event-free survival of 84.6 % in G-I and 81.1% in G-II (P=0.57. CONCLUSION: Percutaneous treatment with coronary stent implantation in young patients with multivessel disease may be safe with a high rate of clinical success, a low incidence of in-hospital complications, and a favorable evolution in clinical follow-up.

  5. Association Between Helicobacter Pylori Infection and Long-term Outcome in Patients with Drug-eluting Stent Implantation

    Science.gov (United States)

    Wang, Rui; Chen, Lei-Lei; Wang, De-Zhao; Chen, Bu-Xing

    2017-07-01

    To investigate the relationship between Helicobacter pylori (Hp) infection and the long-term outcome in acute coronary syndrome (ACS) patients with drug-eluting stent (DES) implantation and so as to explore the significance of Hp eradication therapy in preventing major adverse cardiac events (MACE) and upper gastrointestinal bleeding (UGIB). 539 ACS patients with DES implantation from January 1, 2010 to December 31, 2012 were analyzed. All the patients were divided into two groups according to the result of 13C urea breath test. 253 patients with Hp infection were put into group A (Hp+), and 286 cases without Hp infection were put into group B (Hp-). Demographic data was collected and all patients went through biochemical indicators and other routine blood examinations. We explored the correlations of Hp infection with MACE and UGIB after 3 to 5 years of follow-up using survival analysis. Survival analysis showed that Hp infection was a predictor of MACE and UGI. Sub-group analysis showed that patients with Hp eradication therapy had no relationship with MACE but had a lower rate of UGIB than those without Hp eradication therapy.

  6. Duration of balloon inflation for optimal stent deployment: five seconds is not enough.

    Science.gov (United States)

    Hovasse, Thomas; Mylotte, Darren; Garot, Philippe; Salvatella, Neus; Morice, Marie-Claude; Chevalier, Bernard; Pichard, Augusto; Lefèvre, Thierry

    2013-02-01

    To assess the effect of the duration of stent inflation on stent expansion using digital stent enhancement (DSE). Optimal stent expansion and apposition to the vessel wall are of critical importance to optimize the results of percutaneous coronary intervention (PCI). However, it is not known if stent inflation duration impacts on stent expansion. We performed a prospective cohort study in patients undergoing PCI. Quantitative coronary angiography and DSE data were analyzed. DSE was performed at 5, 15, and 25 sec during stent implantation, after target balloon inflation pressure was achieved. One hundred and four consecutive patients (150 lesions) were enrolled. The mean age was 66.9 ± 11.1 years. Complex lesions (ACC/AHA B2/C) occurred in 26.9%. Stents used: Cypher Select (54.1%), Xience V (30.6%), and Taxus Liberté (15.3%). The minimal stent diameter increased significantly with the duration of stent inflation: 2.60 ± 0.51, 2.76 ± 0.51, and 2.82 ± 0.52 mm at 5, 15, and 25 sec (P inflation: 3.21 ± 0.51, 3.32 ± 0.52, and 3.36 ± 0.54 mm (P inflation (P inflation has a significant impact on stent expansion. Stent deployment for >25 sec is recommended. Copyright © 2012 Wiley Periodicals, Inc.

  7. Ultrasound thrombolysis in stent thrombosis.

    Science.gov (United States)

    Rassin, T; Desmet, W; Piessens, J; Rosenschein, U

    2000-11-01

    Recent refinement in stent implantation technique and peri-procedural pharmacological treatment has lowered the incidence of stent thrombosis significantly. Still, all stent thromboses are associated with major adverse events. In previous studies it has been suggested that intravascular ultrasound fibrinolysis is safe and effective. In this report, ultrasound successfully reperfused thrombotically occluded stents. These observations suggest that ultrasound may dissolve occlusive platelet-rich thrombus effectively and safely. Cathet. Cardiovasc. Intervent. 51:332-334, 2000. Copyright 2000 Wiley-Liss, Inc.

  8. Quality assessment of pacemaker implantations in Denmark

    DEFF Research Database (Denmark)

    Møller, M; Arnsbo, P; Asklund, Mogens

    2002-01-01

    AIMS: Quality assessment of therapeutic procedures is essential to insure a cost-effective health care system. Pacemaker implantation is a common procedure with more than 500,000 implantations world-wide per year, but the general complication rate is not well described. We studied procedure related...... complications for all implantations performed in an entire nation over a 3-year period. METHODS AND RESULTS: A prospective study of complications related to 99% of the 5648 primary pacemaker implantations performed in the 12 Danish pacemaker centres in 1997-1999 was carried out. Overall 76% of the patients...... received a physiological pacemaker system and 91% received the optimal pacing mode according to international guidelines. Perioperative complications requiring reoperation were: haematoma 0.3%, atrial lead related 1.9%, ventricular lead related 1.7%. Late complications requiring reoperation were: infection...

  9. Impact of final kissing balloon inflation after simple stent implantation for the treatment of non-left main true coronary bifurcation lesions in patients with acute coronary syndrome.

    Science.gov (United States)

    Kim, Tae-Hoon; Lee, Hyun Jong; Jang, Ho-Jun; Kim, Je Sang; Park, Jin Sik; Choi, Rak Kyeong; Choi, Young Jin; Shim, Won-Heum; Ro, Young Moo; Yu, Cheol Woong; Kwon, Sung Woo

    2014-12-20

    We sought to evaluate the impact of final kissing balloon inflation (FKBI) after simple stent implantation for the treatment of non-left main true coronary bifurcation lesions in patients with acute coronary syndrome (ACS). Whether FKBI should be mandatory after simple stent implantation for the treatment of coronary bifurcation lesion is controversial. Besides, ACS patients who have undergone bifurcation percutaneous coronary intervention with simple stent implantation may experience worse prognosis compared to stable angina pectoris patients. Two hundred and fifty one eligible patients (67.7% male, mean age 61.7 ± 10.4 years) were enrolled. The study population was divided into two groups according to the performance of FKBI. The primary end points were major adverse cardiac event (MACE); target lesion revascularization (TLR), non-fatal myocardial infarction (MI) and cardiac death during the follow-up period. Over a mean follow-up period of 3.0 ± 1.9 years, there were 29 MACEs (10 TLR, 6 non-fatal MI, and 13 cardiac deaths), representing an event rate of 11.6%. Kaplan-Meier survival analysis revealed that FBKI group had favorable outcome compared to non-FKBI group with regard to hard events (p = 0.010) as well as composite MACEs (p = 0.008). In multivariable analysis, FKBI was a significant predictor of composite MACEs [hazard ratio 0.398 (95% confidence interval 0.190-0.836, p = 0.015)] and hard events [hazard ratio 0.325 (95% confidence interval 0.130-0.811, p = 0.016)]. In terms of prognosis, performing FKBI after simple stent implantation for the treatment of non-left main true coronary bifurcation lesions may be mandatory in ACS patients. Copyright © 2014. Published by Elsevier Ireland Ltd.

  10. Three-year-old child with middle aortic syndrome treated by endovascular stent implantation.

    Science.gov (United States)

    Moszura, Tomasz; Goreczny, Sebastian; Dryzek, Pawel; Niwald, Marek

    2013-04-01

    Middle aortic syndrome (MAS) is an extremely rare anomaly and represents both a diagnostic and therapeutic challenge, particularly in young children. A case of a 3.5 year-old child with MAS and arterial hypertension is reported, where owing to the patient's young age and the length of the hypoplastic aortic segment, surgical correction with end-to-end anastomosis was not feasible. Instead of palliative bypass grafting between the thoracic and abdominal aorta, successful percutaneous balloon angioplasty and stenting of the lesion was performed with the assistance of three-dimensional rotational angiography.

  11. Circumferential stent fracture repaired using a covered stent in a 42-year-old man with coarctation of the aorta.

    Science.gov (United States)

    Ayoub, Fares; AlShelleh, Sameeha; A L-Ammouri, Iyad

    2016-02-01

    We present a case of circumferential fracture of aortic coarctation stent with severe re-stentosis presenting 16 years after initial stent implantation with end-stage renal disease. The patient was treated with a covered stent using the stent-in-stent technique. The use of an ultra-high-pressure balloon was proved necessary to overcome the tight, non-compliant stenosis.

  12. CT angiography after carotid artery stenting: assessment of the utility of adaptive statistical iterative reconstruction and model-based iterative reconstruction

    Energy Technology Data Exchange (ETDEWEB)

    Kuya, Keita; Shinohara, Yuki; Fujii, Shinya; Ogawa, Toshihide [Tottori University, Division of Radiology, Department of Pathophysiological Therapeutic Science, Faculty of Medicine, Yonago (Japan); Sakamoto, Makoto; Watanabe, Takashi [Tottori University, Division of Neurosurgery, Department of Brain and Neurosciences, Faculty of Medicine, Yonago (Japan); Iwata, Naoki; Kishimoto, Junichi [Tottori University, Division of Clinical Radiology Faculty of Medicine, Yonago (Japan); Kaminou, Toshio [Osaka Minami Medical Center, Department of Radiology, Osaka (Japan)

    2014-11-15

    Follow-up CT angiography (CTA) is routinely performed for post-procedure management after carotid artery stenting (CAS). However, the stent lumen tends to be underestimated because of stent artifacts on CTA reconstructed with the filtered back projection (FBP) technique. We assessed the utility of new iterative reconstruction techniques, such as adaptive statistical iterative reconstruction (ASIR) and model-based iterative reconstruction (MBIR), for CTA after CAS in comparison with FBP. In a phantom study, we evaluated the differences among the three reconstruction techniques with regard to the relationship between the stent luminal diameter and the degree of underestimation of stent luminal diameter. In a clinical study, 34 patients who underwent follow-up CTA after CAS were included. We compared the stent luminal diameters among FBP, ASIR, and MBIR, and performed visual assessment of low attenuation area (LAA) in the stent lumen using a three-point scale. In the phantom study, stent luminal diameter was increasingly underestimated as luminal diameter became smaller in all CTA images. Stent luminal diameter was larger with MBIR than with the other reconstruction techniques. Similarly, in the clinical study, stent luminal diameter was larger with MBIR than with the other reconstruction techniques. LAA detectability scores of MBIR were greater than or equal to those of FBP and ASIR in all cases. MBIR improved the accuracy of assessment of stent luminal diameter and LAA detectability in the stent lumen when compared with FBP and ASIR. We conclude that MBIR is a useful reconstruction technique for CTA after CAS. (orig.)

  13. 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)

  14. ACTH- and cortisol-associated neutrophil modulation in coronary artery disease patients undergoing stent implantation.

    Directory of Open Access Journals (Sweden)

    Margit Keresztes

    Full Text Available Psychosocial stress and activation of neutrophil granulocytes are increasingly recognized as major risk factors of coronary artery disease (CAD, but the possible relationship of these two factors in CAD patients is largely unexplored. Activation of neutrophils was reported to be associated with stenting; however, the issue of neutrophil state in connection with percutaneous coronary intervention (PCI is incompletely understood from the aspect of stress and its hypothalamic-pituitary-adrenal axis (HPA background. Thus, we aimed to study cortisol- and ACTH-associated changes in granulocyte activation in patients undergoing PCI.Blood samples of 21 stable angina pectoris (SAP and 20 acute coronary syndrome (ACS patients were collected directly before (pre-PCI, after (post-PCI and on the following day of PCI (1d-PCI. Granulocyte surface L-selectin, CD15 and (neutrophil-specific lactoferrin were analysed by flow cytometry. Plasma cortisol, ACTH, and lactoferrin, IL-6 were also assayed. In both groups, pre- and post-PCI ratios of lactoferrin-bearing neutrophils were relatively high, these percentages decreased substantially next day; similarly, 1d-PCI plasma lactoferrin was about half of the post-PCI value (all p≤0.0001. Post-PCI ACTH was reduced markedly next day, especially in ACS group (SAP: p<0.01, ACS: p≤0.0001. In ACS, elevated pre-PCI cortisol decreased considerably a day after stenting (p<0.01; in pre-PCI samples, cortisol correlated with plasma lactoferrin (r∼0.5, p<0.05. In 1d-PCI samples of both groups, ACTH showed negative associations with the ratio of lactoferrin-bearing neutrophils (SAP: r = -0.601, p<0.005; ACS: r = -0.541, p<0.05 and with plasma lactoferrin (SAP: r = -0.435, p<0.05; ACS: r = -0.609, p<0.005.Pre- and post-PCI states were associated with increased percentage of activated/degranulated neutrophils indicated by elevated lactoferrin parameters, the 1d-PCI declines of which were associated with plasma

  15. In-vitro hemodynamics of stented bioprosthetic heart valves in the tilted implantation position.

    Science.gov (United States)

    Babin-Ebell, Joerg; Sievers, Hans H; Misfeld, Martin; Runge, Maike; Vogt, Paul Robert; Scharfschwerdt, Michael

    2008-09-01

    Although, in small aortic annulus or aortic annulus calcification, it is recommended that valves are implanted in a tilted position, mechanical valves show impaired hemodynamic performance when positioned in this way. To date, no investigations have been conducted with biological valves implanted in a tilted position. Measurements were performed in a pulsatile flow simulator. The aortic roots were mounted in a fluid reservoir and tested with bioprosthetic valves implanted in the regular position (21 mm; n = 7) or at a 200 tilt (23 mm; n = 7). Additional 21 mm valves were implanted in both positions with a systemic pressure of 120/80 mmHg. Subsequently, the valves were implanted into a glass model and flow visualization monitored by adding air bubbles illuminated with a laser diode. The 21 mm valves showed a slightly higher transvalvular gradient in the tilted than in the regular position, while 23 mm valves in a tilted position showed a lower gradient than 21 mm valves in the regular position. Flow in the regular position was seen to be straight and central, but in the tilted position was diverted and impacted on the aortic wall. Vortex formation in the tilted position was more pronounced than in the regular position, with certain low-flow areas being observed. The implantation of a one size-larger bioprosthetic valve at a 20 degree tilt in a small aortic root resulted in a slight reduction in transvalvular gradient compared to a smaller valve implanted in the regular position. Whilst mechanical valve performance is markedly compromised in the tilted position, the bioprosthetic valve showed only minor impairment of transvalvular pressure gradient due to tilting, and this was overcompensated by the larger valve size. However, the advantage of a greater orifice area must be traded against the consequences of the observed flow disturbances.

  16. Comparison of intravascular ultrasound versus angiography-guided drug-eluting stent implantation: A meta-analysis of one randomised trial and ten observational studies involving 19,619 patients

    NARCIS (Netherlands)

    Y. Zhang (Yaojun); V. Farooq (Vasim); H.M. Garcia-Garcia (Hector); C.V. Bourantas (Christos); N.-L. Tian (Nai-Liang); S.-J. Dong (Sheng-Jie); M. Li (Minghui); S. Yang (Shengyun); P.W.J.C. Serruys (Patrick); S.-L. Chen (Shao-Liang)

    2012-01-01

    textabstractAims: The impact of intravascular ultrasound (IVUS) guided coronary drug-eluting stent (DES) implantation on clinical outcomes remains controversial. A meta-analysis of the currently available clinical trials investi-gating IVUS-guided DES implantation was undertaken. Methods and

  17. Study design of the influence of SErotonin inhibition on patients with RENAl impairment or diabetes undergoing drug-eluting stent implantation (SERENADE) study: A multicenter, open-label, prospective, randomized study.

    Science.gov (United States)

    Lee, Seung-Ah; Suh, Jung-Won; Park, Jin Joo; Yoon, Chang-Hwan; Cho, Young-Suk; Youn, Tae-Jin; Chae, In-Ho; Kim, Hyo-Soo; Kim, Sang-Hyun; Choi, Dong-Ju

    2015-07-01

    The rates of stent failure after percutaneous coronary intervention have decreased since the introduction of the drug-eluting stent (DES). However, chronic kidney disease (CKD) and diabetes mellitus (DM) remain strong clinical predictors of poor prognosis despite DES implantation. Sarpogrelate, a selective serotonin (5-hydroxytryptamine (HT)2a [5-HT2A]) receptor antagonist, has antiproliferative effects, reducing neointimal hyperplasia and smooth muscle cell proliferation, as well as potent antiplatelet action, inhibiting 5-HT-induced platelet aggregation. However, efficacy and safety data for sarpogrelate in patients with CKD or DM are limited. We aim to determine whether sarpogrelate has beneficial effects in patients with CDK or DM treated with DES implantation. The SERENADE trial is a multicenter, open-label, prospective, randomized study that will test the superiority of triple anti-platelet therapy (TAT; aspirin, clopidogrel, and sarpogrelate) to conventional dual antiplatelet therapy (DAT; aspirin and clopidogrel) in preventing late lumen loss 9 months after the index procedure in patients with CKD or DM. A total of 220 patients diagnosed with coronary artery disease with DM or CKD will be randomized to the TAT or DAT groups (1:1 ratio) after DES implantation. The primary endpoint is late lumen loss at 9 months assessed by quantitative coronary angiography. Secondary efficacy endpoints are composites of major adverse cardiovascular events including cardiac death, nonfatal myocardial infarction, and target lesion revascularization. Secondary safety endpoints are major bleeding events and hepatic or renal impairment. The SERENADE trial will provide insight on the efficacy of adjunctive therapy with sarpogrelate after DES implantation for patients with high-risk profiles such as CKD or DM. National Institutes of Health Clinical Trials Registry (ClinicalTrials.gov NCT02294643). Copyright © 2015. Published by Elsevier Inc.

  18. 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

    ón geográfica sobre los desenlaces clínicos con el stent liberador de zotarolimus se evaluó en tres regiones: Pacífico Asiático, Europa y América Latina. MÉTODOS: A total of 8,314 patients (6.572 Europe, 1.522 Asia Pacific, and 220 Latin America were followed for 1 year; 2.116 of these (1.613, 316, and 187, respectively were followed for 2 years. Patient and lesion characteristics, dual antiplatelet therapy, and clinical outcomes were compared between Latin America and the other regions. RESULTADOS: Los pacientes en América Latina tuvieron la mayor proporción de factores de riesgo e infarto de miocardio previo. Hubo un rápido descenso en el uso de la terapia antiplaquetaria en América Latina, el 44,9% en 6 meses para 22,5% en 1 año y 7,8% en 2 años (Europa: un 87,4%, un 61,5%, un 19,7%; Pacífico Asiático: un 82,4%, un 67,0%, un 45,7%, respectivamente. No hubo diferencias significativas entre América Latina y Europa o Pacífico Asiático para cualquier desenlace en cualquier momento. La incidencia de trombosis de stent probable y definitiva por el Academic Research Consortium fue baja (BACKGROUND: Differences between geographic regions in patient characteristics and outcomes, particularly for acute coronary syndromes, have been demonstrated in clinical trials. Clinical outcomes after percutaneous coronary interventions with the Zotarolimus-eluting stent in a real-world population were assessed over time. OBJECTIVE: The influence of geographic location on clinical outcomes with the Zotarolimus-eluting stent was assessed in 3 regions: Asia Pacific, Europe, and Latin America. METHODS: A total of 8,314 patients (6,572 Europe, 1,522 Asia Pacific, and 220 Latin America were followed for 1 year; 2,116 of these (1,613, 316, and 187, respectively were followed for 2 years. Patient and lesion characteristics, dual antiplatelet therapy, and clinical outcomes were compared between Latin America and the other regions. RESULTS: Patients in Latin America had the highest

  19. Stent thrombosis and bleeding complications after implantation of sirolimus-eluting coronary stents in an unselected worldwide population: a report from the e-SELECT (Multi-Center Post-Market Surveillance) registry.

    Science.gov (United States)

    Urban, Philip; Abizaid, Alexandre; Banning, Adrian; Bartorelli, Antonio L; Baux, Ana Cebrian; Džavík, Vladimír; Ellis, Stephen; Gao, Runlin; Holmes, David; Jeong, Myung Ho; Legrand, Victor; Neumann, Franz-Josef; Nyakern, Maria; Spaulding, Christian; Worthley, Stephen

    2011-03-29

    The aim of this study was to ascertain the 1-year incidence of stent thrombosis (ST) and major bleeding (MB) in a large, unselected population treated with sirolimus-eluting stents (SES). Stent thrombosis and MB are major potential complications of drug-eluting stent implantation. Their relative incidence and predisposing factors among large populations treated worldwide are unclear. The SES were implanted in 15,147 patients who were entered in a multinational registry. We analyzed the incidence of: 1) definite and probable ST as defined by the Academic Research Consortium; and 2) MB, with the STEEPLE (Safety and efficacy of Enoxaparin in PCI) definition, together with their relation to dual antiplatelet therapy (DAPT) and to 1-year clinical outcomes. The mean age of the sample was 62 ± 11 years, 30.4% were diabetic, 10% had a Charlson comorbidity index ≥3, and 44% presented with acute coronary syndrome or myocardial infarction. At 1 year, the reported compliance with DAPT as recommended by the European Society of Cardiology guidelines was 86.3%. Adverse event rates were: ST 1.0%, MB 1.0%, mortality 1.7%, myocardial infarction 1.9%, and target lesion revascularization 2.3%. Multivariate analysis identified 9 correlates of ST and 4 correlates of MB. Advanced age and a high Charlson index were associated with an increased risk of both ST and MB. After ST, the 7-day and 1-year all-cause mortality was 30% and 35%, respectively, versus 1.5% and 10% after MB. Only 2 of 13,749 patients (0.015%) experienced both MB and ST during the entire 1-year follow-up period. In this worldwide population treated with ≥1 SES, the reported compliance with DAPT was good, and the incidence of ST and MB was low. Stent thrombosis and MB very rarely occurred in the same patient. (The e-SELECT Registry: a Multicenter Post-Market Surveillance; NCT00438919). Copyright © 2011 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  20. A Case of Pseudoaneurysm of the Internal Carotid Artery Following Endoscopic Endonasal Pituitary Surgery: Endovascular Treatment with Flow-Diverting Stent Implantation

    Directory of Open Access Journals (Sweden)

    Ali Karadag

    2017-10-01

    Full Text Available Internal carotid artery (ICA pseudoaneurysm is a rare complication of endoscopic endonasal surgery occurring in 0.4–1.1% of cases. Pseudoaneurysms can subsequently result in other complications, such as subarachnoid hemorrhage, epistaxis, and caroticocavernous fistula with resultant death or permanent neurologic deficit. In this case, we illustrate endovascular treatment with a flow-diverting stent for an ICA pseudoaneurysm after endoscopic endonasal surgery for a pituitary adenoma in a 56-year-old male. Surgery was complicated by excessive intraoperative bleeding and emergent CT angiography confirmed an iatrogenic pseudoaneurysm on the anteromedial surface of the ICA. The pseudoaneurysm was treated endovascularly with flow-diverting stent implantation only. Follow-up CT angiography after three months demonstrated occlusion of the pseudoaneurysm.

  1. Hemodynamics in Transplant Renal Artery Stenosis and its Alteration after Stent Implantation Based on a Patient-specific Computational Fluid Dynamics Model.

    Science.gov (United States)

    Wang, Hong-Yang; Liu, Long-Shan; Cao, Hai-Ming; Li, Jun; Deng, Rong-Hai; Fu, Qian; Zhang, Huan-Xi; Fei, Ji-Guang; Wang, Chang-Xi

    Accumulating studies on computational fluid dynamics (CFD) support the involvement of hemodynamic factors in artery stenosis. Based on a patient-specific CFD model, the present study aimed to investigate the hemodynamic characteristics of transplant renal artery stenosis (TRAS) and its alteration after stent treatment. Computed tomography angiography (CTA) data of kidney transplant recipients in a single transplant center from April 2013 to November 2014 were reviewed. The three-dimensional geometry of transplant renal artery (TRA) was reconstructed from the qualified CTA images and categorized into three groups: the normal, stenotic, and stented groups. Hemodynamic parameters including pressure distribution, velocity, wall shear stress (WSS), and mass flow rate (MFR) were extracted. The data of hemodynamic parameters were expressed as median (interquartile range), and Mann-Whitney U-test was used for analysis. Totally, 6 normal, 12 stenotic, and 6 stented TRAs were included in the analysis. TRAS presented nonuniform pressure distribution, adverse pressure gradient across stenosis throat, flow vortex, and a separation zone at downstream stenosis. Stenotic arteries had higher maximal velocity and maximal WSS (2.94 [2.14, 3.30] vs. 1.06 [0.89, 1.15] m/s, 256.5 [149.8, 349.4] vs. 41.7 [37.8, 45.3] Pa at end diastole, P= 0.001; 3.25 [2.67, 3.56] vs. 1.65 [1.18, 1.72] m/s, 281.3 [184.3, 364.7] vs. 65.8 [61.2, 71.9] Pa at peak systole, P= 0.001) and lower minimal WSS and MFRs (0.07 [0.03, 0.13] vs. 0.52 [0.45, 0.67] Pa, 1.5 [1.0, 3.0] vs. 11.0 [8.0, 11.3] g/s at end diastole, P= 0.001; 0.08 [0.03, 0.19] vs. 0.70 [0.60, 0.81] Pa, 2.0 [1.3, 3.3] vs. 16.5 [13.0, 20.3] g/s at peak systole, P= 0.001) as compared to normal arteries. Stent implantation ameliorated all the alterations of the above hemodynamic factors except low WSS. Hemodynamic factors were significantly changed in severe TRAS. Stent implantation can restore or ameliorate deleterious change of hemodynamic

  2. Hemodynamics in Transplant Renal Artery Stenosis and its Alteration after Stent Implantation Based on a Patient-specific Computational Fluid Dynamics Model

    Science.gov (United States)

    Wang, Hong-Yang; Liu, Long-Shan; Cao, Hai-Ming; Li, Jun; Deng, Rong-Hai; Fu, Qian; Zhang, Huan-Xi; Fei, Ji-Guang; Wang, Chang-Xi

    2017-01-01

    Background: Accumulating studies on computational fluid dynamics (CFD) support the involvement of hemodynamic factors in artery stenosis. Based on a patient-specific CFD model, the present study aimed to investigate the hemodynamic characteristics of transplant renal artery stenosis (TRAS) and its alteration after stent treatment. Methods: Computed tomography angiography (CTA) data of kidney transplant recipients in a single transplant center from April 2013 to November 2014 were reviewed. The three-dimensional geometry of transplant renal artery (TRA) was reconstructed from the qualified CTA images and categorized into three groups: the normal, stenotic, and stented groups. Hemodynamic parameters including pressure distribution, velocity, wall shear stress (WSS), and mass flow rate (MFR) were extracted. The data of hemodynamic parameters were expressed as median (interquartile range), and Mann–Whitney U-test was used for analysis. Results: Totally, 6 normal, 12 stenotic, and 6 stented TRAs were included in the analysis. TRAS presented nonuniform pressure distribution, adverse pressure gradient across stenosis throat, flow vortex, and a separation zone at downstream stenosis. Stenotic arteries had higher maximal velocity and maximal WSS (2.94 [2.14, 3.30] vs. 1.06 [0.89, 1.15] m/s, 256.5 [149.8, 349.4] vs. 41.7 [37.8, 45.3] Pa at end diastole, P = 0.001; 3.25 [2.67, 3.56] vs. 1.65 [1.18, 1.72] m/s, 281.3 [184.3, 364.7] vs. 65.8 [61.2, 71.9] Pa at peak systole, P = 0.001) and lower minimal WSS and MFRs (0.07 [0.03, 0.13] vs. 0.52 [0.45, 0.67] Pa, 1.5 [1.0, 3.0] vs. 11.0 [8.0, 11.3] g/s at end diastole, P = 0.001; 0.08 [0.03, 0.19] vs. 0.70 [0.60, 0.81] Pa, 2.0 [1.3, 3.3] vs. 16.5 [13.0, 20.3] g/s at peak systole, P = 0.001) as compared to normal arteries. Stent implantation ameliorated all the alterations of the above hemodynamic factors except low WSS. Conclusions: Hemodynamic factors were significantly changed in severe TRAS. Stent implantation can restore or

  3. 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

    DEFF Research Database (Denmark)

    Zbinden, Rainer; von Felten, Stefanie; Wein, Bastian

    2017-01-01

    AIMS: 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 3 mm in diameter. We analyzed the impact of 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. METHODS/RESULTS: 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...... of 10 000 CHF per TLR avoided, DES had a high probability of being cost-effective. CONCLUSION: 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...

  4. External heating of stents by radio waves: pilot studies in rabbit aorta.

    Science.gov (United States)

    Levitt, Adam B; Robinson, Keith; Chronos, Nicolas A F; Daum, Wolfgang

    2003-01-01

    This experiment was designed to assess the feasibility of radio frequency energy delivered by a prototype radio frequency generator inductive heating device (REVAX) positioned external to the body, for transient heating of stents after arterial implant. Twenty-one New Zealand White rabbits underwent stenting of their infrarenal aorta. Nine rabbits were stented and immediately placed in the REVAX for external stent heating with internal temperature probes in place. Twelve rabbits were stented and 3 days later either heated or placed in the generator as a sham for 20 min. The animals were terminated 28 days later. The REVAX was able to heat the aortic stents in a controlled fashion; in Phase II experiments, the stent temperature was raised to 42 degrees C for 20 min. In Phase I mild necrosis was noted at the stent struts. In Phase II, necrosis and mineralization of the media was seen at the stent struts, and evidence of neointimal suppression was observed. This study demonstrated that external heating of stents in a blood vessel in a live animal via radio frequency energy is feasible. Further studies will be needed to assess whether any specific heating regimen might inhibit fibrocellular neointimal hyperplasia.

  5. Quantification of in-stent restenosis parameters in rabbits by micro-CT

    International Nuclear Information System (INIS)

    Langheinrich, A.C.; Zoerb, C.; Jajima, J.; Lommel, D.; Rau, W.S.; Walker, G.; Mueller, K.M.; Bohle, R.M.

    2005-01-01

    Purpose: The well-defined model of angioplasty and stent implantation in the rabbit aorta is useful in experimental studies of restenosis. This study was performed to evaluate the feasibility of Micro-CT for quantification of in-stent restenosis in a rabbit aortic in-stent restenosis model. Material and Methods: To induce in-stent restenosis seven female New Zealand rabbits underwent balloon dilation and denudation prior to stenting the abdominal aorta. After six weeks on atherogenic diet, animals were killed and the aorta was perfused with contrast agent. Micro-CT morphometric analysis of balloon and stent injured arteries obtained by 700 transverse sections (voxel size 10 μm) was compared to conventional histological analysis. Results: Intimal hyperplasia was present in stented and balloon injured arteries with a moderate intimal area assessed by Micro-CT and conventional histology (3.91±0.5 mm 2 vs. 4.18±0.42; r=0.9). High significant correlations between Micro-CT image analysis and conventional histomorphometry were obtained for lesion size, size of media, size of lumen and stent area (r=0.84 to 0.96). Conclusion: Micro-CT is feasible for quantitative information about restenosis following balloon angioplasty and stent implantation and has the potential to become a standard technique in many laboratories which will augment serial histology as the reference method for ex-vivo studies of restenosis. (orig.)

  6. 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

    Directory of Open Access Journals (Sweden)

    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

  7. Transcatheter aortic valve implantation using anatomically oriented, marrow stromal cell-based, stented, tissue-engineered heart valves: technical considerations and implications for translational cell-based heart valve concepts.

    Science.gov (United States)

    Emmert, Maximilian Y; Weber, Benedikt; Behr, Luc; Sammut, Sebastien; Frauenfelder, Thomas; Wolint, Petra; Scherman, Jacques; Bettex, Dominique; Grünenfelder, Jürg; Falk, Volkmar; Hoerstrup, Simon P

    2014-01-01

    While transcatheter aortic valve implantation (TAVI) has rapidly evolved for the treatment of aortic valve disease, the currently used bioprostheses are prone to continuous calcific degeneration. Thus, autologous, cell-based, living, tissue-engineered heart valves (TEHVs) with regeneration potential have been suggested to overcome these limitations. We investigate the technical feasibility of combining the concept of TEHV with transapical implantation technology using a state-of-the-art transcatheter delivery system facilitating the exact anatomical position in the systemic circulation. Trileaflet TEHVs fabricated from biodegradable synthetic scaffolds were sewn onto self-expanding Nitinol stents seeded with autologous marrow stromal cells, crimped and transapically delivered into the orthotopic aortic valve position of adult sheep (n = 4) using the JenaValve transapical TAVI System (JenaValve, Munich, Germany). Delivery, positioning and functionality were assessed by angiography and echocardiography before the TEHV underwent post-mortem gross examination. For three-dimensional reconstruction of the stent position of the anatomically oriented system, a computed tomography analysis was performed post-mortem. Anatomically oriented, transapical delivery of marrow stromal cell-based TEHV into the orthotopic aortic valve position was successful in all animals (n = 4), with a duration from cell harvest to TEHV implantation of 101 ± 6 min. Fluoroscopy and echocardiography displayed sufficient positioning, thereby entirely excluding the native leaflets. There were no signs of coronary obstruction. All TEHV tolerated the loading pressure of the systemic circulation and no acute ruptures occurred. Animals displayed intact and mobile leaflets with an adequate functionality. The mean transvalvular gradient was 7.8 ± 0.9 mmHg, and the mean effective orifice area was 1.73 ± 0.02 cm(2). Paravalvular leakage was present in two animals, and central aortic regurgitation due to a

  8. Gender difference on five-year outcomes of EXCEL biodegradable polymer-coated sirolimus-eluting stents implantation: results from the CREATE study.

    Science.gov (United States)

    Zhang, Lei; Qiao, Bing; Han, Ya-Ling; Li, Yi; Xu, Kai; Zhang, Quan-Yu; Yang, Li-Xia; Liu, Hui-Liang; Xu, Bo; Gao, Run-Lin

    2013-03-01

    biodegradable polymer-coated sirolimus-eluting stenting in long term follow-up. Effects of prolonged dual antiplatelet therapy (DAPT) in preventing stent thrombosis was similar with six-month DAPT after EXCEL stent implantation in both men and women groups.

  9. Stent implantation to ductus arteriosus in a patient with interrupted aortic arch guided by CT image overlay.

    Science.gov (United States)

    Goreczny, Sebastian; Dryzek, Pawel; Moszura, Tomasz

    2017-08-01

    A 15-day-old premature patient with ventricular septal defect and interrupted aortic arch type B underwent "hybrid" initial treatment consisting of bilateral pulmonary artery banding followed by stenting of the ductus arteriosus. A pre-registered CT scan was re-purposed with a new three-dimensional image fusion software (VesselNavigator) to create a roadmap for stent delivery.

  10. A Novel Attempt to Standardize Results of CFD Simulations Basing on Spatial Configuration of Aortic Stent-Grafts.

    Directory of Open Access Journals (Sweden)

    Andrzej Polanczyk

    Full Text Available Currently, studies connected with Computational Fluid Dynamic (CFD techniques focus on assessing hemodynamic of blood flow in vessels in different conditions e.g. after stent-graft's placement. The paper propose a novel method of standardization of results obtained from calculations of stent-grafts' "pushing forces" (cumulative WSS--Wall Shear Stress, and describes its usefulness in diagnostic process. AngioCT data from 27 patients were used to reconstruct 3D geometries of stent-grafts which next were used to create respective reference cylinders. We made an assumption that both the side surface and the height of a stent-graft and a reference cylinder were equal. The proposed algorithm in conjunction with a stent-graft "pushing forces" on an implant wall, allowed us to determine which spatial configuration of a stent-graft predispose to the higher risk of its migration. For stent-grafts close to cylindrical shape (shape factor φ close to 1 WSS value was about 267 Pa, while for stent-grafts different from cylindrical shape (φ close to 2 WSS value was about 635 Pa. It was also noticed that deformation in the stent-graft's bifurcation part impaired blood flow hemodynamic. Concluding the proposed algorithm of standardization proved its usefulness in estimating the WSS values that may be useful in diagnostic process. Angular bends or tortuosity in bifurcations of an aortic implant should be considered in further studies of estimation of the risk of implantation failure.

  11. Overtime evaluation of the vascular HEALing process after everolimus-eluting stent implantation by optical coherence tomography. The HEAL-EES study

    Energy Technology Data Exchange (ETDEWEB)

    Otsuki, Shuji; Brugaletta, Salvatore, E-mail: sabrugal@clinic.ub.es; Sabaté, Manel; Shiratori, Yoshitaka; Gomez-Monterrosas, Omar; Scalone, Giancarla; Romero-Villafañe, Sebastian; Hernández-Enríquez, Marco; Freixa, Xavier; Martín-Yuste, Victoria; Masotti, Mónica

    2016-06-15

    Purpose: Second-generation drug-eluting stent (DES) have shown a better safety and efficacy as compared to first generation DES due to an improved vascular healing process. This process has not been so far evaluated in vivo in an overtime fashion by optical coherent tomography (OCT). We sought to evaluate the vascular healing process after everolimus-eluting stent (EES) implantation at 6, 9 and 12 months, by OCT. Methods: Consecutive 36 patients undergoing percutaneous coronary intervention with EES were randomized 1:1:1 to receive OCT imaging at 6 (group A), 9 (group B) or 12-month follow-up (group C). One patient from group C was excluded because of target lesion revascularization at 1-month, whereas 5 patients withdraw the informed consent. Finally, 30 patients were analyzed. Results: Neointimal thickness was not different between 3 groups (group A: 99.50 [94.06–127.79] μm, group B: 107.26 [83.48–133.59] μm, group C: 127.67 [102.51–138.49] μm; p = 0.736). Although the percentage of “uncovered struts” was significantly higher in group A as compared to the other groups (8.0% vs. 4.4% vs. 2.9%, respectively; p = 0.180), the ratio of uncovered to total struts per section < 30% was similar between 3 groups (0.3% vs. 0.3% vs. 0%, respectively; p = 1.000). Conclusion: Healing process following EES implantation seems almost completed at 6-month follow-up. These data, which need to be confirmed in a larger study, may support the decision to shorten dual antiplatelet therapy. - Highlights: • Healing process following everolimus-eluting stent implantation is complete at 6-month • There are no difference in RUTTS > 30% between 6, 9 and 12 months analyses. • This finding may support to shorten dual antiplatelet therapy in this context.

  12. 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

    Directory of Open Access Journals (Sweden)

    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

  13. Quantitative Assessment of Orbital Implant Position - A Proof of Concept

    NARCIS (Netherlands)

    Schreurs, Ruud; Dubois, Leander; Becking, Alfred G.; Maal, Thomas J. J.

    2016-01-01

    Introduction In orbital reconstruction, the optimal location of a predefined implant can be planned preoperatively. Surgical results can be assessed intraoperatively or postoperatively. A novel method for quantifying orbital implant position is introduced. The method measures predictability of

  14. Quantitative assessment of orbital implant position - a proof of concept

    NARCIS (Netherlands)

    Schreurs, R.; Dubois, L.; Becking, A.G.; Maal, T.J.J.

    2016-01-01

    Introduction In orbital reconstruction, the optimal location of a predefined implant can be planned preoperatively. Surgical results can be assessed intraoperatively or postoperatively. A novel method for quantifying orbital implant position is introduced. The method measures predictability of

  15. Predictors of long-term outcomes after bypass grafting versus drug-eluting stent implantation for left main or multivessel coronary artery disease

    NARCIS (Netherlands)

    Chang, Mineok; Lee, Cheol Whan; Ahn, Jung-Min; Cavalcante, Rafael; Sotomi, Yohei; Onuma, Yoshinobu; Han, Minkyu; Park, Seong-Wook; Serruys, Patrick W.; Park, Seung-Jung

    2017-01-01

    Background: We assessed predictors of long-term outcomes after coronary artery bypass grafting (CABG) versus those after percutaneous coronary intervention (PCI) with drug-eluting stents (DES) in 3,230 patients with left main or multivessel coronary artery disease (CAD). Methods and Results: Data

  16. Avaliação angiográfica do volume de placa e eventos cardiovasculares após implante de stents coronarianos

    Directory of Open Access Journals (Sweden)

    Erlon Oliveira de Abreu-Silva

    2010-12-01

    Full Text Available FUNDAMENTO: O volume de placa (VP está relacionado a eventos cardiovasculares maiores (ECVM após o implante de stents coronarianos. OBJETIVO: Avaliar a associação entre o VP antes do procedimento avaliado por angiografia e desfechos clínicos. MÉTODOS: Trata-se de estudo de coorte prospectivo incluindo pacientes submetidos a implante de stents coronarianos em um centro de referência. O VP antes do implante do stent foi avaliado pela fórmula descrita por Giugliano (Am J Cardiol 2005; 95:173: VP = À X (comprimento da lesão X [(diâmetro do vaso/2² - (diâmetro luminal mínimo/2²]. Os ECVM foram registrados no seguimento clínico de um ano e análise de regressão linear múltipla foi realizada para identificar os preditores de eventos. RESULTADOS: A amostra estudada consistiu em 824 pacientes, com idade média de 60 ± 11 anos, sendo 70,0% do gênero masculino. O diabete melito estava presente em 21,0% e o comprometimento triarterial em 12,0%. O diâmetro médio de referência foi de 3,3 ± 3,2 mm, a média do comprimento da lesão foi de 10,2 ± 4,7 mm e a média da estenose residual foi de 1,0% ± 12,0%. Os pacientes com ECVM apresentaram VP maior do que aqueles sem eventos (92,84 ± 42,85 vs 85 ± 46,85; p = 0,03. Outras variáveis associadas com ECVM na análise univariada foram comprometimento triarterial, IAM, diâmetro do vaso e comprimento da lesão tratada. O VP manteve a associação significativa com ECVM após ajuste para as variáveis descritas e diabete melito. CONCLUSÃO: O volume da placa do ateroma antes do implante do stent foi maior nos pacientes que apresentaram ECVM no seguimento clínico em um ano, independentemente de outros preditores de eventos.

  17. CMR assessment after a transapical-transcatheter aortic valve implantation

    Energy Technology Data Exchange (ETDEWEB)

    Biere, Loïc, E-mail: lobiere@chu-angers.fr [L’UNAM Université, Angers (France); Université d’Angers, Laboratoire Cardioprotection, Remodelage et Thrombose, CHU d’Angers, Service de Cardiologie, Angers (France); Pinaud, Frédéric [L’UNAM Université, Angers (France); Université d’Angers, CHU d’Angers, Service de Chirurgie Cardio-vasculaire et Thoracique, Angers (France); UMR-CNRS 6214, INSERM 1083, faculté de médecine, Angers (France); Delépine, Stéphane; Grall, Sylvain; Viot, Nathalie; Mateus, Victor; Rouleau, Frédéric [L’UNAM Université, Angers (France); Université d’Angers, Laboratoire Cardioprotection, Remodelage et Thrombose, CHU d’Angers, Service de Cardiologie, Angers (France); Corbeau, Jean-Jacques [Université d’Angers, CHU d’Angers, Département d’anesthésie-réanimation, Angers (France); Prunier, Fabrice [L’UNAM Université, Angers (France); Université d’Angers, Laboratoire Cardioprotection, Remodelage et Thrombose, CHU d’Angers, Service de Cardiologie, Angers (France); and others

    2014-02-15

    Aims: To describe the time course of myocardial scarring after transapical-transcatheter aortic valve implantation (TA-TAVI) with the Edwards SAPIEN XT™ and the Edwards SAPIEN™ prosthesis in a 3-month follow-up study using cardiac magnetic resonance imaging (CMR). Methods: In 20 TA-TAVI patients, CMR was performed at discharge and 3 months (3M). Cine-MRI was used for left ventricular (LV) functional assessment, and late gadolinium enhancement (LGE) imaging was employed for detecting the presence of myocardial scarring. Special attention was given to any artifacts caused by the prosthesis, which were consequently defined using a three-grade artifact scale. Results: We systematically reported the presence of small LGE hyperintensity relating to the apical segment, with no variation found between discharge and 3 M (2.8 ± 1.6 g vs. 2.35 ± 1.1 g). LV ejection fraction, end-diastolic, and end-systolic volumes did not significantly vary. A small area of apical akinesia was observed, with no improvement at follow-up. Whereas the Edwards SAPIEN XT™ prosthesis and the Edwards SAPIEN™ prosthesis are both constituted by metallic stenting structure, the Edwards SAPIEN™ was responsible for a larger signal void, thus potentially limiting the diagnostic performance of CMR. Conclusions: CMR may be performed safely in the context of TA-TAVI. The presence of a very small apical infarction correlating with focal akinesia was observed. As expected, the Edwards SAPIEN XT™ prosthesis was shown to be particularly suitable for CMR assessment.

  18. Biomedical implants and devices: assessment of magnetic field interactions with a 3.0-Tesla MR system.

    Science.gov (United States)

    Shellock, Frank G

    2002-12-01

    To evaluate magnetic field interactions for 109 different biomedical implants and devices in association with exposure to a 3.0-Tesla magnetic resonance (MR) system. A total of 109 implants and devices (aneurysm clips, 32; clips, fasteners, and staples, 10; coils and stents, 10; heart valve prostheses and annuloplasty rings, 12; orthopedic implants, five; suture materials, 13; vascular access ports and accessories, 13; miscellaneous implants and devices, 14) were tested for magnetic field interactions at 3.0-Tesla using previously-described, standardized techniques to assess magnetic field translational attraction and torque. The deflection angles and torque measurements ranged, respectively, from 0 to 16 degrees and 0 to +2 for the aneurysm clips; 0 to 90 degrees and 0 to +4 for the clips, fasteners, and staples; 0 to 47 degrees and 0 to +4 for the coils and stents; 0 to 4 degrees and 0 to +1 for the heart valve prostheses and annuloplasty rings; 0 to 12 degrees and 0 to +2 for the orthopedic implants; 0 to 13 degrees and 0 to +2 for the suture materials; 0 to 52 degrees and 0 to +4 for the vascular access ports and accessories; and 0 to 28 degrees and 0 to +3 for the miscellaneous implants and devices. Of the 109 implants and devices assessed for magnetic field interactions at 3.0-Tesla, four (4%) are potentially unsafe based on deflection angle criteria. The implications of these results for patients undergoing MR procedures at 3.0-Tesla is discussed. Notably, these results are specific to the 3.0-Tesla MR system used for this evaluation. Copyright 2002 Wiley-Liss, Inc.

  19. Combined stent implantation and embolization with liquid 2-polyhydroxyethyl methacrylate for treatment of experimental canine wide-necked aneurysms

    International Nuclear Information System (INIS)

    Klisch, J.; Zitt, J.; Schumacher, M.; Schellhammer, F.; Scheufler, K.M.; Pagenstecher, A.; Nagursky, H.

    2002-01-01

    The purpose of the study was the evaluation of 2-polyhydroxyethyl methacrylate (2-P-HEMA) for endovascular liquid embolization of experimental side-wall aneurysms following stent protection in a canine model. The swelling behaviour and polymerization characteristics of 2-P-HEMA in different solutions were investigated in vitro. Different methods for applications were tested in a latex aneurysm model under pulsatile flow conditions. Twenty broad-based carotid side-wall aneurysms were microsurgically produced in five dogs. Four weeks after surgery self-expandable nitinol stents were placed, covering the orifice of the aneurysms. 2-P-HEMA was injected via a microcatheter, which was positioned through the meshwork of the stent. Control angiography was performed immediately after treatment and after 1, 6 and 9 months. In-vivo stent placement succeeded in all but one case. Two aneurysms occluded spontaneously after stent placement. Combined embolization of 17 aneurysms using a stent and 2-P-HEMA was performed. Eleven aneurysms could be primarily completely occluded (65%). A small remaining neck was evident in six aneurysms. Efflux of 2-P-HEMA during the process of embolization was observed in seven aneurysms, due to an excess volume of 2-P-HEMA. The excessive 2-P-HEMA led to significant vessel stenosis in two cases. Two carotid arteries (three treated aneurysms) occluded after 1 month, due to insufficient anticoagulation management. Histological examination of embolized aneurysms revealed no foreign-body or inflammatory reaction. A smooth neo-intimal layer covered the stented vessel segment. Liquid embolization of side-wall aneurysms with 2-P-HEMA is technically feasible. Embolotherapy of aneurysms with liquid agents still has the risk that embolic material will exit even when it is stent-protected. To avoid this problem, stents with smaller strut diameter and/or additional balloon-protection are required. The inert 2-P-HEMA seems to be a promising agent for combining

  20. Course of thrombin activation markers in patients implanted with Palmaz-Schatz stents: first experiences with a post-interventional anticoagulation regimen.

    Science.gov (United States)

    Haushofer, A; Halbmayer, W M; Dittel, M; Prachar, H; Mlczoch, J; Fischer, M

    1994-10-01

    Following implantation of coronary Palmaz-Schatz stents, 29 patients were anticoagulated with a combination of heparin, phenprocoumon and aspirin following a standard protocol. After removing the arterial and venous lines, post-interventional intravenous (i.v.) heparin treatment started with 1500 IU/h for patients > 80 kg and 1250 IU/h for patients < 80 kg. Heparin was monitored by the activated partial thromboplastin time (aPTT) and adjusted by increasing or reducing i.v. heparin by 250 IU/h to maintain the aPTT within the therapeutic range. Phenprocoumon therapy began the day after stent implantation (day 2) and lasted for 3 months. aPTT, Heptest, prothrombin fragment F1 and 2 (F1.2) and thrombin-antithrombin III complexes (TAT) were monitored at standard intervals for 10 days (mean monitoring time: 9.7 +/- 2.3 days). Anticoagulation was efficient with aPTT levels remaining within the therapeutic range on day 9 and the simultaneous, moderate-onset oral anticoagulation within the therapeutic range of the International Normalized Ratio (INR; 2.15-4.80) on day 8 on average, the mean INR being 2.43 +/- 0.76. On day 4, F1.2 levels were significantly higher than on the day of stenting (1.16 +/- 0.30 nmol/l vs 1.04 +/- 0.53 nmol/l; P < 0.005). F1.2 levels fell after day 5, the difference becoming significant from day 8 on (P < 0.05). F1.2 was negatively correlated with the Heptest (P < 0.05) and fell significantly as a function of the INR during phenprocoumon administration (P < 0.001). After phenprocoumon therapy was discontinued over 3 weeks, 25 patients were followed up by angiography. Despite adequate anticoagulation, mean F1.2 levels in patients showing restenosis at follow-up angiography were significantly higher (P < 0.005) than in those without restenosis. In one patient who developed subacute stent thrombosis, clotting factors were determined 20 min before stent occlusion. The levels of F1.2 and TAT were less than all other patients on this day (F1.2: 0.98 nmol

  1. Flat-detector computed tomography in the assessment of intracranial stents: comparison with multi detector CT and conventional angiography in a new animal model

    International Nuclear Information System (INIS)

    Struffert, Tobias; Ott, Sabine; Adamek, Edyta; Schwarz, Marc; Engelhorn, Tobias; Kloska, Stephan; Doerfler, Arnd; Deuerling-Zheng, Yu

    2011-01-01

    Careful follow up is necessary after intracranial stenting because in-stent restenosis (ISR) or residual stenosis (RS) is not rare. A minimally invasive follow-up imaging technique is desirable. The objective was to compare the visualisation of stents in Flat Detector-CT Angiography (FD-CTA) after intravenous contrast medium injection (i.v.) with Multi Detector Computed Tomography Angiography (MD-CTA) and Digital Subtracted Angiography (DSA) in an animal model. Stents were implanted in the carotid artery of 12 rabbits. In 6 a residual stenosis (RS) was surgically created. Imaging was performed using FD-CTA, MD-CTA and DSA. Measurements of the inner and outer diameter and cross-section area of the stents were performed. Stenosis grade was calculated. In subjective evaluation FD-CTA was superior to MD-CTA. FD-CTA was more accurate compared with DSA than MD-CTA. Cross-sectional area of the stent lumen was significantly larger (p < 0.05) in FD-CTA in comparison to MD-CTA. Accurate evaluation of stenosis was impossible in MD-CTA. There was no statistically significant difference in the stenosis grade of DSA and FD-CTA. Our results show that visualisation of stent and stenosis using intravenous FD-CTA compares favourably with DSA and may replace DSA in the follow-up of patients treated with intracranial stents. (orig.)

  2. Profile of patients assessed for cochlear implants

    Directory of Open Access Journals (Sweden)

    Maria Helena de Magalhães Barbosa

    2014-07-01

    Full Text Available INTRODUCTION: Knowledge of the characteristics related to profound hearing loss is a matter of great importance, as it allows for the etiological and prognostic identification and strategic planning for public health interventions. OBJECTIVE: To assess the different etiologies of hearing loss, age at diagnosis of the hearing loss, its relation to language acquisition, and the age at the first consultation in this service for cochlear implant assessment. METHODS: This was a historical cohort, cross-sectional study, using retrospective analysis of the records of 115 patients with confirmed sensorineural hearing loss, who were followed in a university hospital, based on gender, age of hearing loss, age at the first consultation, language, and hearing loss etiology. RESULTS AND CONCLUSION: The majority of patients assessed for cochlear implants attend the first consultation when they are older than one year (an alarming mean of 3.8 years in the prelingual group in spite of the early diagnosis of hearing loss. This reflects an already deficient health care system, in terms of referral. The idiopathic cause remains the most frequently identified. Among the known causes, the most prevalent are perinatal causes and meningitis.

  3. Intravascular ultrasound-guided vs angiography-guided drug-eluting stent implantation in complex coronary lesions: Meta-analysis of randomized trials.

    Science.gov (United States)

    Bavishi, Chirag; Sardar, Partha; Chatterjee, Saurav; Khan, Abdur Rahman; Shah, Arpit; Ather, Sameer; Lemos, Pedro A; Moreno, Pedro; Stone, Gregg W

    2017-03-01

    The relative outcomes of intravascular ultrasound (IVUS)-guided percutaneous coronary intervention (PCI) compared with angiography-guided PCI with drug-eluting stent (DES) in complex lesions have not been established. We sought to compare the efficacy and safety of IVUS-guided PCI with angiography-guided PCI in patients with complex coronary lesions treated with DES. Electronic databases were searched to identify all randomized trials comparing IVUS-guided vs angiography-guided DES implantation. We evaluated major adverse cardiac events (MACE), all-cause and cardiovascular death, myocardial infarction, target lesion revascularization (TLR), target vessel revascularization (TVR), and stent thrombosis outcomes at the longest reported follow-up. Random-effects modeling was used to calculate pooled relative risk (RR) and 95% CIs. Eight trials comprising 3,276 patients (1,635 IVUS-guided and 1,641 angiography-guided) enrolling only patients with complex lesions were included. Mean follow-up was 1.4±0.5years. Compared with angiography-guided PCI, patients undergoing IVUS-guided PCI had significantly lower MACE (RR 0.64, 95% CI 0.51-0.80, P=.0001), TLR (RR 0.62, 95% CI 0.45-0.86, P=.004), and TVR (RR 0.60, 95% CI 0.42-0.87, P=.007). There were no significant differences for stent thrombosis, cardiovascular death, or all-cause death. In meta-regression analysis, IVUS-guided PCI was of greatest benefit in reducing MACE in patients with acute coronary syndromes, diabetes, and long lesions. The present meta-analysis demonstrates a significant reduction in MACE, TVR, and TLR with IVUS-guided DES implantation in complex coronary lesions. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. A review with meta-analysis of observational studies for survival following off-pump coronary artery bypass versus drug-eluting stent implantation.

    Science.gov (United States)

    Takagi, Hisato; Watanabe, Taku; Mizuno, Yusuke; Kawai, Norikazu; Umemoto, Takuya

    2014-06-01

    To determine whether off-pump coronary artery bypass (OPCAB) improves survival over drug-eluting stent (DES) implantation, we performed a review with meta-analysis of exclusive OPCAB versus DES. Databases including MEDLINE, EMBASE and the Cochrane Central Register of Controlled Trials were searched through October 2013 using Web-based search engines (PubMed and OVID). Studies that met the following criteria were considered for inclusion: the design was a randomized controlled trial or observational comparative study; the study population was patients with any coronary artery disease; patients were assigned to OPCAB versus DES and outcomes included all-cause mortality at ≥1 years. Our exhaustive search identified no randomized trial and 10 observational studies of OPCAB versus DES. A pooled analysis demonstrated no statistically significant difference in all-cause mortality between OPCAB and DES (hazard ratio, 0.94; 95% confidence interval, 0.76-1.15; P = 0.55). In general, exclusion of any single study from the analysis did not substantially alter the overall result of our analysis. There was no evidence of significant publication bias. In conclusion, OPCAB may not improve survival over DES despite greater number of treated vessels in OPCAB than in DES or greater number of distal anastomosis in OPCAB than that of implanted stents in DES. © The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

  5. Percutaneous pulmonary valve implantation preceded by routine prestenting with a bare metal stent

    DEFF Research Database (Denmark)

    Demkow, Marcin; Biernacka, Elzbieta Katarzyna; Spiewak, Mateusz

    2011-01-01

    with routine prestenting have never been reported. Methods: Consecutive patients who underwent PPVI for homograft dysfunction with prestenting with BMS were studied. The schedule of follow-up assessment comprised clinical evaluation, cardiovascular magnetic resonance, transthoracic echocardiography, and chest...

  6. Metallic intratracheal stent application on relapsing polychondritis with severe tracheobronchial malacia

    International Nuclear Information System (INIS)

    Ao Guokun; Zhao Weiguo; Guo Qinyun; Huang Qin

    2007-01-01

    Objective: To evaluate the therapeutic and adverse effects of metallic intratracheal stent placement in relapsing polychondritis with severe tracheobronchial malaeia. Methods: Five tracheal stents had been implanted in three patients with tracheobronchial malaeia. One patient was implanted with two tubular stents in trachea and one 'Y' shaped stent for bilateral bronchi. Another patient used a tubular stent in total tracheal segment. The last patient used a tubular stent in the upper segment of trachea. Results: All the stents were implanted successfully with obvious improvement of dyspnea after the treatment. Conclusions: Metallic intratracheal stent placement can really relieve symptoms and improve the life quality in patients with tracheobronchial malacia caused by relapsing polychondritis. (authors)

  7. 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

  8. Intravascular ultrasound-guided drug-eluting stent implantation: An updated meta-analysis of randomized control trials and observational studies.

    Science.gov (United States)

    Steinvil, Arie; Zhang, Yao-Jun; Lee, Sang Yeub; Pang, Si; Waksman, Ron; Chen, Shao-Liang; Garcia-Garcia, Hector M

    2016-08-01

    The use of intravascular ultrasound (IVUS) guidance for drug-eluting stent (DES) optimization is limited by the number of adequately powered randomized control trials (RCTs). We performed an updated meta-analysis, including data from recently published RCTs and observational studies, by reviewing the literature in Medline and the Cochrane Library to identify studies that compared clinical outcomes between IVUS-guided and angiography-guided DES implantation from January 1995 to January 2016. This meta-analysis included 25 eligible studies, including 31,283 patients, of whom 3192 patients were enrolled in 7 RCTs. In an analysis of all 25 studies, the summary results for all the events analyzed were significantly in favor of IVUS-guided DES implantation [major adverse cardiac events (MACE, odds ratio [OR] 0.76, 95% confidence intervals [CI]: 0.70-0.82, PDES implantation was found only for MACE (OR 0.66, 95% CI: 0.52-0.84, P=0.001), TLR (OR 0.61, 95% CI: 0.43-0.87, P=0.006), and TVR (OR 0.61, 95% CI: 0.41-0.90, P=0.013). IVUS-guided percutaneous coronary intervention was associated with better overall clinical outcomes than angiography-guided DES implantation. However, in a solely RCT meta-analysis, this benefit was mainly driven by reduced rates of revascularizations. Copyright © 2016. Published by Elsevier Ireland Ltd.

  9. Vascular injury post stent implantation: different gene expression modulation in human umbilical vein endothelial cells (HUVECs model.

    Directory of Open Access Journals (Sweden)

    Jonica Campolo

    Full Text Available To explore whether stent procedure may influence transcriptional response of endothelium, we applied different physical (flow changes and/or mechanical (stent application stimuli to human endothelial cells in a laminar flow bioreactor (LFB system. Gene expression analysis was then evaluated in each experimental condition. Human umbilical vein endothelial cells (HUVECs were submitted to low and physiological (1 and 10 dyne/cm(2 shear stress in absence (AS or presence (PS of stent positioning in a LFB system for 24 h. Different expressed genes, coming from Affymetrix results, were identified based on one-way ANOVA analysis with p values 3 in modulus. Low shear stress was compared with physiological one in AS and PS conditions. Two major groups include 32 probes commonly expressed in both 1AS versus 10AS and 1PS versus 10PS comparison, and 115 probes consisting of 83 in addition to the previous 32, expressed only in 1PS versus 10PS comparison. Genes related to cytoskeleton, extracellular matrix, and cholesterol transport/metabolism are differently regulated in 1PS versus 10PS condition. Inflammatory and apoptotic mediators seems to be, instead, closely modulated by changes in flow (1 versus 10, independently of stent application. Low shear stress together with stent procedure are the experimental conditions that mainly modulate the highest number of genes in our human endothelial model. Those genes belong to pathways specifically involved in the endothelial dysfunction.

  10. Intracoronary local paclitaxel delivery by X-ray contrast media for in-stent restenosis: a clinical pilot study to assess safety and tolerability.

    Science.gov (United States)

    Rutsch, W; Scheller, B; Borges, A C; Bräutigam, M; Clever, Y; Cremers, B; Dietz, U; Richter, W; Speck, U

    2012-08-01

    Non-stent-based immediate release formulations of paclitaxel have been shown to reduce in-stent restenosis in animal experiments and clinical trials. In the porcine overstretch model paclitaxel dissolved in the contrast medium iopromide inhibited neointimal proliferation in a dose-dependent manner after intracoronary injection and was well tolerated. As a first step entering clinical development, a phase I trial was performed using four ascending paclitaxel dose/concentration levels: samples of up to 100 mL of the contrast medium (iopromide) containing 10, 50, 100 or 200 µM paclitaxel or iopromide (controls) were randomly administered to patients assigned to bare metal stent implantation for single de novo coronary artery lesions. Safety variables, tolerability and angiographic parameters were assessed. Adverse events, ECG, systolic and diastolic blood pressure, left ventricular ejection fraction, leukocyte count, other hematological or clinical chemistry data did not reveal any trend which could be related to the study medication. Short-lasting serum paclitaxel concentrations remained significantly below those known from cancer therapy. Angiographic late lumen loss was 0.72±0.50 mm (N.=7) in controls versus 0.45±0.65 mm (N.=17) in all paclitaxel-treated patients; binary restenosis rate was 5/7(63%) versus 6/17 (35%) and target lesion revascularization rate was 4/8 (50%) versus 4/24 (17%). Intracoronary infusion of paclitaxel dissolved in an X-ray contrast medium was well tolerated. The results show restenosis inhibition, but the number of patients examined was too small to demonstrate a statistically significant inhibition.

  11. Imaging of pediatric great vessel stents: Computed tomography or magnetic resonance imaging?

    Directory of Open Access Journals (Sweden)

    A M den Harder

    Full Text Available Complications might occur after great vessel stent implantation in children. Therefore follow-up using imaging is warranted.To determine the optimal imaging modality for the assessment of stents used to treat great vessel obstructions in children.Five different large vessel stents were evaluated in an in-vitro setting. All stents were expanded to the maximal vendor recommended diameter (20mm; n = 4 or 10mm; n = 1, placed in an anthropomorphic chest phantom and imaged with a 256-slice CT-scanner. MRI images were acquired at 1.5T using a multi-slice T2-weighted turbo spin echo, an RF-spoiled three-dimensional T1-weighted Fast Field Echo and a balanced turbo field echo 3D sequence. Two blinded observers assessed stent lumen visibility (measured diameter/true diameter *100% in the center and at the outlets of the stent. Reproducibility of diameter measurements was evaluated using the intraclass correlation coefficient for reliability and 95% limits of agreement for agreement analysis.Median stent lumen visibility was 88 (IQR 86-90% with CT for all stents at both the center and outlets. With MRI, the T2-weighted turbo spin echo sequence was preferred which resulted in 82 (78-84% stent lumen visibility. Interobserver reliability and agreement was good for both CT (ICC 0.997, mean difference -0.51 [-1.07-0.05] mm and MRI measurements (ICC 0.951, mean difference -0.05 [-2.52 --2.41] mm.Good in-stent lumen visibility was achievable in this in-vitro study with both CT and MRI in different great vessel stents. Overall reliability was good with clinical acceptable limits of agreement for both CT and MRI. However, common conditions such as in-stent stenosis and associated aneurysms were not tested in this in-vitro study, limiting the value of the in-vitro study.

  12. Intimal hyperplasia and vascular remodeling after everolimus-eluting and sirolimus-eluting stent implantation in diabetic patients

    DEFF Research Database (Denmark)

    Antonsen, Lisbeth; Maeng, Michael; Thayssen, Per

    2014-01-01

    in 88 patients, including 48 EES and 40 SES treated patients. IVUS endpoints included IH volume, in-stent % volume obstruction and changes in external elastic membrane (EEM) volume. RESULTS: Compared with the SES group, IH volume was increased in the EES group [median (interquartile range): 2.8 mm(3) (0.......0-12.6) vs. 0.0 mm(3) (0.0-1.1), P = 0.001]. In-stent % volume obstruction was increased in EES compared to SES [median (interquartile range): 1.6% (0.0-8.2) vs. 0.0% (0.0-1.0), P = 0.001]. Peri-stent external elastic membrane (EEM) volume: (post procedure vs. follow-up EES [300 mm(3) (219-491) vs. 307 mm(3...

  13. 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.

  14. Multicenter assessment of the reproducibility of volumetric radiofrequency-based intravascular ultrasound measurements in coronary lesions that were consecutively stented

    DEFF Research Database (Denmark)

    Huisman, Jennifer; Egede, Rasmus; Rdzanek, Adam

    2012-01-01

    To assess in a multicenter design the between-center reproducibility of volumetric virtual histology intravascular ultrasound (VH-IVUS) measurements with a semi-automated, computer-assisted contour detection system in coronary lesions that were consecutively stented. To evaluate the reproducibility...

  15. Scanning electron microscopic assessment of coating irregularities and their precursors in unexpanded durable polymer-based drug-eluting stents

    NARCIS (Netherlands)

    Basalus, M.W.; Tandjung, K.; Tandjung, K.; van Westen, T.; Sen, H.; van der Jagt, P.K.N.; Grijpma, Dirk W.; van Apeldoorn, Aart A.; von Birgelen, Clemens

    2012-01-01

    Objectives: To assess and quantify coating irregularities on unexpanded and expanded durable polymer-based drug-eluting stents (DES) to gain insights into the origin of coating irregularities. Background: Previous scanning electron microscopy (SEM) studies in various expanded DES revealed

  16. [Changes in antithrombin III, prothrombin fragment 1 + 2 and thrombin-antithrombin III complex following implantation of a coronary Palmaz-Schatz stent].

    Science.gov (United States)

    Dittel, M; Haushofer, A; Spiel, R; Halbmayer, W M; Prachar, H; Fischer, M; Mlczoch, J

    1995-01-01

    To detect changes in the clotting parameters antithrombin III (AT III), prothrombin-fragment 1 + 2 (F 1 + 2) and thrombin-antithrombin-III-complex (TAT) after implantation of Palmaz Schatz stents, coagulation was monitored at standardized time points in 35 patients for 10 days. All patients were anticoagulated using a combination of heparin, phenprocoumon, and acetyl salicylic acid. Heparin therapy was guided by APTT levels (normal range 25-35 s), which were still within the therapeutic range (median 49.6 s (25%/75% percentiles 41.6/54.4) on day 10. Simultaneous oral anticoagulation was found to be effective on day 8 on average (INR median 2.24 (1.93/2.50)). The AT III activity dropped significantly (p < 0.0001) after a heparin loading dose of 15,000 IU during stenting. As the heparin dose was reduced on the following days, AT III levels increased significantly (p < 0.0001) during the observation time. There was a highly significant (p < 0.001) negative correlation between AT III and heparin levels. On days 4 and 5 F 1 + 2 values were significantly (p < 0.001 and p < 0.05) higher than on the day of stenting (median 1.07 (0.90/1.31) 1.13 nmol/l and 1.06 (0.85/1.23) nmol/l vs. 0.97 (0.69/1.15) nmol/l) and dropped during anticoagulation. F 1 + 2 levels showed a significant negative correlation (p < 0.0005) with APTT values. TAT values showed no significant changes during the observation period.(ABSTRACT TRUNCATED AT 250 WORDS)

  17. Long-term clinical efficacy of cutting balloon angioplasty followed by bare metal stent implantation for treating ostial left anterior descending artery lesions.

    Science.gov (United States)

    Gao, Li-Jian; Chen, Ji-Lin; Chen, Jun; Yang, Yue-Jin; Gao, Run-Lin; Li, Jian-Jun; Qin, Xue-Wen; Qiao, Shu-Bin; Xu, Bo; Yao, Min; Liu, Hai-Bo; Wu, Yong-Jian; Yuan, Jin-Qing; Chen, Jue; You, Shi-Jie; Dai, Jun

    2009-08-01

    Drug-eluting stents (DES) are superior to bare metal stents (BMS) for treating ostial left anterior descending artery (LAD) lesions, but DES is not suitable for all patients in real life practice. We hypothesize that cutting balloon angioplasty (CBA) followed by BMS (CBA + BMS) for treating ostial LAD lesions is an alternative strategy. In our study, 101 consecutive patients (51 with DES and 50 with CBA + BMS) with ostial LAD stenting were included for retrospective investigation between November 2003 and May 2005. The target vessel diameter was > or =3.0 mm. We compared the DES group with the CBA + BMS group, the rates of restenosis (10.3% versus 17.9%, p = 0.386), target lesion revascularization (TLR) (5.88% versus 10%, p = 0.487) and major adverse cardiac events (MACE) (7.84% versus 12%, p = 0.525) were similar at 6-8 months angiographic follow-up, but there were higher bleeding events in the DES group (p = 0.033). During a 2-year clinical follow-up, no myocardial infarction occurred in the 2 groups, the rates of TLR (7.84% versus 10%, p = 0.741) and MACE (9.8% versus 12%, p = 0.723) were also similar. The MACE-free survival rate was 90.2% versus 88 % (p = 0.723). The CBA + BMS combination has a good long-term clinical effect in the treatment of ostial LAD lesions; it might be an alternative strategy for patients with contraindication for DES implantation, or patients who cannot endure long-term dual antiplatelet medication, or in elderly patients.

  18. Is quantitative coronary angiography reliable in assessing the late lumen loss of the everolimus-eluting bioresorbable polylactide scaffold in comparison with the cobalt-chromium metallic stent?

    NARCIS (Netherlands)

    Sotomi, Yohei; Onuma, Yoshinobu; Miyazaki, Yosuke; Asano, Taku; Katagiri, Yuki; Tenekecioglu, Erhan; Jonker, Hans; Dijkstra, Jouke; de Winter, Robbert J.; Wykrzykowska, Joanna J.; Stone, Gregg W.; Popma, Jeffrey J.; Kozuma, Ken; Tanabe, Kengo; Serruys, Patrick W.; Kimura, Takeshi

    2017-01-01

    Aims: Immediately after stent/scaffold implantation, quantitative coronary angiography (QCA) in comparison to optical coherence tomography (OCT) more severely underestimates the lumen diameter (LD) in Absorb than in XIENCE. This OCT-QCA discrepancy has not been evaluated at long-term follow-up. The

  19. Biocompatibility of new drug-eluting biodegradable urethral stent materials.

    Science.gov (United States)

    Kotsar, Andres; Nieminen, Riina; Isotalo, Taina; Mikkonen, Joonas; Uurto, Ilkka; Kellomäki, Minna; Talja, Martti; Moilanen, Eeva; Tammela, Teuvo L J

    2010-01-01

    To investigate the effects of biodegradable stent material (poly-96L/4D-lactic acid [PLA]) on the production of cytokines and other inflammatory mediators in vitro and the biocompatibility of new drug-eluting biodegradable urethral stent materials in vivo. Indomethacin, dexamethasone, and simvastatin were used in the materials. The effects of the biodegradable stent material on cytokines and other inflammatory mediators were measured using the Human Cytokine Antibody Array and enzyme-linked immunosorbent assay in THP-1 cells, with bacterial lipopolysaccharide as a positive control. To assess the biocompatibility of the stent materials, we used muscle implantation. Biodegradable stent materials without drug-eluting properties and silicone and latex were used as controls. The measurements were done at 3 weeks and 3 months. The PLA stent material induced production of inflammatory mediators, especially interleukin-8, tumor necrosis factor-alpha, and transforming growth factor-beta, in vitro. The increase in the production of these mediators with the PLA stent material was smaller than in the cells treated with lipopolysaccharide. In vivo, the effects of the biodegradable materials did not differ at 3 weeks, although, at 3 months, dexamethasone had induced more tissue reactions than had the other materials. At 3 months, fibrosis and chronic inflammatory changes were decreased in the biodegradable material groups compared with the positive control. PLA stent material increased the production of cytokines and other inflammatory mediators less than did positive controls in vitro. The in vivo biocompatibility of the drug-eluting biodegradable materials was better than that of the positive controls. Drug-eluting biodegradable urethral stents could potentially offer a new treatment modality in the future. 2010 Elsevier Inc. All rights reserved.

  20. Favorable effect of optimal lipid-lowering therapy on neointimal tissue characteristics after drug-eluting stent implantation: qualitative optical coherence tomographic analysis.

    Science.gov (United States)

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

    2015-10-01

    Serial follow-up optical coherence tomography (OCT) was used to evaluate the effect of optimal lipid-lowering therapy on qualitative changes in neointimal tissue characteristics after drug-eluting stent (DES) implantation. DES-treated patients (n = 218) who received statin therapy were examined with serial follow-up OCT. First and second follow-up OCT evaluations were performed approximately 6 and 18 months after the index procedure, respectively. Patients were divided into two groups, based on the level of low-density lipoprotein-cholesterol (LDL-C), which was measured at the second follow-up. The optimal lipid-lowering group (n = 121) had an LDL-C reduction of ≥50% or an LDL-C level ≤70 mg/dL, and the conventional group (n = 97). Neointimal characteristics were qualitatively categorized as homogeneous or non-homogeneous patterns using OCT. The non-homogeneous group included heterogeneous, layered, or neoatherosclerosis patterns. Qualitative changes in neointimal tissue characteristics between the first and second follow-up OCT examinations were assessed. Between the first and second follow-up OCT procedures, the neointimal cross-sectional area increased more substantially in the conventional group (0.4 mm(2) vs. 0.2 mm(2) in the optimal lipid-lowering group, p = 0.01). The neointimal pattern changed from homogeneous to non-homogeneous less often in the optimal lipid-lowering group (1.3%, 1/77, p < 0.001) than in the conventional group (15.3%, 11/72, p = 0.44). Optimal LDL-C reduction was an independent predictor for the prevention of neointimal pattern change from homogeneous to non-homogeneous (odds ratio: 0.05, 95% confidence interval: 0.01∼0.46, p = 0.008). Our findings suggest that an intensive reduction in LDL-C levels can prevent non-homogeneous changes in the neointima and increases in neointimal cross-sectional area compared with conventional LDL-C controls. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  1. Systemic Assessment of Patients Undergoing Dental Implant ...

    African Journals Online (AJOL)

    Background: Procedure‑related and patient‑related factors influence the prognosis of dental implants to a major extent. Hence, we aimed to evaluate and analyze various systemic factors in patients receiving dental implants. Materials and Methods: Fifty‑one patients were included in the study, in which a total of 110 dental ...

  2. Systemic Assessment of Patients Undergoing Dental Implant ...

    African Journals Online (AJOL)

    These days, dental implants are becoming routinely used as a treatment option for rehabilitation of lost teeth. Conventionally, it is only after the completion of bone healing that the dental implants are loaded into the bone. Bone healing time is approximately 3 months and. 6 months for the mandible and maxilla, respectively.

  3. Comparative vascular responses three months after paclitaxel and everolimus-eluting stent implantation in streptozotocin-induced diabetic porcine coronary arteries

    Directory of Open Access Journals (Sweden)

    Sheehy Alexander

    2012-06-01

    Full Text Available Abstract Background Diabetes remains a significant risk factor for restenosis/thrombosis following stenting. Although vascular healing responses following drug-eluting stent (DES treatment have been characterized previously in healthy animals, comparative assessments of different DES in a large animal model with isolated features of diabetes remains limited. We aimed to comparatively assess the vascular response to paclitaxel-eluting (PES and everolimus-eluting (EES stents in a porcine coronary model of streptozotocin (STZ-induced type I diabetes. Method Twelve Yucatan swine were induced hyperglycemic with a single STZ dose intravenously to ablate pancreatic β-cells. After two months, each animal received one XIENCE V® (EES and one Taxus Liberte (PES stent, respectively, in each coronary artery. After three months, vascular healing was assessed by angiography and histomorphometry. Comparative in vitro effects of everolimus and paclitaxel (10-5 M–10-12 M after 24 hours on carotid endothelial (EC and smooth muscle (SMC cell viability under hyperglycemic (42 mM conditions were assayed by ELISA. Caspase-3 fluorescent assay was used to quantify caspase-3 activity of EC treated with everolimus or paclitaxel (10-5 M, 10-7 M for 24 hours. Results After 3 months, EES reduced neointimal area (1.60 ± 0.41 mm, p vs. 0.08 ± 0.05, greater medial necrosis grade (0.52 ± 0.26 vs. 0.0 ± 0.0, and persistently elevated fibrin scores (1.60 ± 0.60 vs. 0.63 ± 0.41 with PES compared to EES (p In vitro, paclitaxel significantly increased (p -7 M, while everolimus did not affect EC/SMC apoptosis/necrosis within the dose range tested. In ECs, paclitaxel (10-5 M significantly increased caspase-3 activity (p  Conclusion After 3 months, both DES exhibited signs of delayed healing in a STZ-induced diabetic swine model. PES exhibited greater neointimal area, increased inflammation, greater medial necrosis, and

  4. Early vascular healing with rapid breakdown biodegradable polymer sirolimus-eluting versus durable polymer everolimus-eluting stents assessed by optical coherence tomography

    Energy Technology Data Exchange (ETDEWEB)

    Tada, Tomohisa, E-mail: tomohisa@dhm.mhn.de [Deutsches Herzzentrum, Technische Universität, München (Germany); Byrne, Robert A. [Deutsches Herzzentrum, Technische Universität, München (Germany); Schuster, Tibor [Institut für Medizinische Statistik und Epidemiologie, München (Germany); Cuni, Rezarta [Deutsches Herzzentrum, Technische Universität, München (Germany); Kitabata, Hironori [Wakayama Medical University, Wakayama (Japan); Tiroch, Klaus [Deutsches Herzzentrum, Technische Universität, München (Germany); Dirninger, Alfred; Gratze, Franz; Kaspar, Klaus; Zenker, Gerald [Landeskrankenhaus Bruck/Mur (Austria); Joner, Michael; Schömig, Albert; Kastrati, Adnan [Deutsches Herzzentrum, Technische Universität, München (Germany)

    2013-03-15

    Background: Differences in early arterial healing patterns after stent implantation between biodegradable and durable polymer based new generation drug-eluting stents are not well understood. The aim of this study was to compare the healing patterns of a novel rapid breakdown (≤ 8 weeks) biodegradable polymer sirolimus-eluting stent (BP-SES) with a durable polymer everolimus-eluting stent (EES) using intravascular optical coherence tomography (OCT) at 4 months. Methods: A total of 20 patients were randomly assigned to stenting with BP-SES (n = 11) or EES (n = 9). Overall intravascular imaging was available for 15 (75%) patients. The primary endpoint was the difference in rate of uncovered struts between BP-SES and EES. To account for strut-level clustering, the results in both treatment groups were compared using a generalized linear mixed model approach. Results: Regarding the primary endpoint, BP-SES as compared to EES showed similar rates of uncovered struts (37 [6.8%] versus 167 [17.5%], odds ratio (OR) 0.45 (95% CI 0.09-2.24), p = 0.33). There were no malapposed struts in BP-SES group and 14 malapposed struts in EES group (p = 0.97). No difference in percent neointimal volume (14.1 ± 8.2% vs. 11.4 ± 6.4%, p = 0.56) was observed. Conclusions: Although rapid-breakdown BP-SES as compared to EES showed signs of improved early tissue coverage, after adjustment for strut-level clustering these differences were not statistically significant. No differences in ability to suppress neointimal hyperplasia after stent implantation between 2 stents were observed.

  5. Microcomputed tomography-based assessment of retrieved dental implants

    NARCIS (Netherlands)

    Narra, N.; Antalainen, A.K.; Zipprich, H.; Sándor, G.K.; Wolff, J.

    2015-01-01

    Purpose: The aim of this study was to demonstrate the potential of microcomputed tomography (micro-CT) technology in the assessment of retrieved dental implants. Cases are presented to illustrate the value of micro-CT imaging techniques in determining possible mechanical causes for dental implant

  6. Microcomputed Tomography-Based Assessment of Retrieved Dental Implants

    NARCIS (Netherlands)

    Narra, N.; Antalainen, A.K.; Zipprich, H.; Sandor, G.K.; Wolff, J.

    2015-01-01

    PURPOSE: The aim of this study was to demonstrate the potential of microcomputed tomography (micro-CT) technology in the assessment of retrieved dental implants. Cases are presented to illustrate the value of micro-CT imaging techniques in determining possible mechanical causes for dental implant

  7. Estenosis de la arteria mesentérica superior como causa de isquemia intestinal crónica: Tratamiento con angioplastia e implante de stent Superior mesenteric artery stenosis as a cause of chronic intestinal ischemia: Treatment with angioplastia and stent implantation

    Directory of Open Access Journals (Sweden)

    Nabil Hamdan

    2005-02-01

    Full Text Available La isquemia intestinal crónica es un cuadro poco frecuente que se asocia con alta morbilidad y mortalidad, cuya causa más frecuente es la arterioesclerosis. Los pacientes sufren de dolor abdominal localizado en epigastrio o periumbilical, que aparece de 10 a 30 minutos luego de la ingestión de alimentos. Se presenta un caso de isquemia intestinal crónica por estenosis de la arteria mesentérica superior disgnosticado por angiografía, el cual se trató con angioplastia percutánea e implante de stent. Se comentan los hallazgos clínicos y radiológicos y el procedimiento terapéutico.Chronic intestinal ischemia is an infrequent clinical presentation associated with high morbidity and mortality; its main cause is arteriosclerosis. Patients suffer abdominal pain localized in the epigastrium or periumbilical region that appears 10 to 30 minutes after food ingestion. A case of chronic intestinal ischemia due to stenosis of the superior mesenteric artery diagnosed through angiography is presented. The treatment consisted of percutaneous angioplastia and Stent implantation. Clinical and radiological findings and therapeutic procedure are discussed.

  8. Tratamiento con angioplastia e implante de stent versus tratamiento quirúrgico en pacientes con estenosis de la arteria carótida cervical Angioplasty treatment and stent implant vs. surgical treatment in patients with stenosis of the cervical carotid artery

    Directory of Open Access Journals (Sweden)

    Nabil Hamdan

    Full Text Available Introducción y objetivos: en el tratamiento de la estenosis significativa de la arteria carótida cervical (común e interna, la angioplastia con implante de stent es un procedimiento menos invasivo que la intervención quirúrgica (5. En la actualidad, en los grandes estudios publicados en los cuales se comparan la angioplastia con el tratamiento quirúrgico, se observan resultados similares en los eventos mayores como accidente cerebrovascular y mortalidad, pero mayor diferencia significativa en la aparición de infarto agudo del miocardio durante la intervención quirúrgica (5, 11. El objetivo de este estudio es comparar en ambos métodos de tratamiento eventos clínicos mayores y menores, como accidente cerebrovascular, infarto agudo del miocardio, muerte, bradicardia, hipotensión y encefalopatía durante la intervención, la hospitalización y al año de seguimiento, además de la reintervención, el tiempo de hospitalización y las complicaciones de la incisión quirúrgica. Materiales y métodos: en este estudio de cohorte histórica, se incluyeron 46 pacientes con estenosis significativa de las arterias carótidas cervicales, quienes se sometieron a intervención desde el 1 de enero de 2001 al 31 de diciembre de 2003. Se trataron 21 pacientes con angioplastia e implante de stent y 25 con cirugía (endarterectomía. Resultados: durante la angioplastia se presentó 1 (4,8% accidente cerebrovascular mayor y ninguno en los pacientes tratados con cirugía. Ocurrió 1 (4% infarto agudo del miocardio durante la intervención en el grupo de pacientes tratados con cirugía y ninguno en los pacientes tratados con angioplastia. No se presentaron muertes en los grupos durante la intervención, la hospitalización y al año de seguimiento. Luego de 8 meses 1 (4,8% paciente tratado con cirugía se reintervino con angioplastia e implante de stent. No hubo diferencias estadísticamente significativas entre ambos grupos durante la hospitalización y

  9. Association of Adventitial Vasa Vasorum and Inflammation With Coronary Hyperconstriction After Drug-Eluting Stent Implantation in Pigs In Vivo.

    Science.gov (United States)

    Nishimiya, Kensuke; Matsumoto, Yasuharu; Shindo, Tomohiko; Hanawa, Kenichiro; Hasebe, Yuhi; Tsuburaya, Ryuji; Shiroto, Takashi; Takahashi, Jun; Ito, Kenta; Ishibashi-Ueda, Hatsue; Yasuda, Satoshi; Shimokawa, Hiroaki

    2015-01-01

    The importance of adventitial inflammation has been implicated for the pathogenesis of coronary artery disease. However, the roles of adventitial changes in drug-eluting stent (DES)-induced coronary hyperconstriction remain largely unknown. In the present study, this issue in pigs in vivo with a special reference to adventitial vasa vasorum (VV) formation and Rho-kinase activation, a central mechanism of coronary vasospasm, was examined. Each animal received a sirolimus-eluting stent (SES) and a biolimus A9-eluting stent (BES), one in the left anterior descending and another in the left circumflex coronary arteries in a randomized manner (n=18). After 1, 3 and 6 months, coronary vasomotion was examined. At 1 month, coronary vasoconstriction to serotonin was significantly enhanced at the SES edges as compared with the BES edges (SES, 52±7% vs. BES, 22±3%, Pmicro-CT showed VV augmentation at the SES site, extending to the proximal and distal edges. Immunostainings demonstrated that VV formation, macrophage infiltration in the adventitia and Rho-kinase expressions/activation were significantly enhanced at the SES edges as compared with the BES edges. The DES with durable polymers enhances VV formation and inflammation in the adventitia, associating with the pathogenesis of DES-induced coronary hyperconstriction through Rho-kinase activation in pigs in vivo.

  10. Endovascular treatment of experimentally induced aneurysms in rabbits using stents: a feasibility study

    International Nuclear Information System (INIS)

    Hans, F.J.; Thiex, R.; Gilsbach, J.M.; Krings, T.; Moeller-Hartmann, W.; Dreeskamp, H.; Stein, K.P.; Meetz, A.; Thron, A.; Pfeffer, J.; Scherer, K.; Brunn, A.

    2003-01-01

    Although Guglielmi detachable coil (GDC) systems have been generally accepted for treatment of intracranial aneurysms, primary stenting of aneurysms using porous stents or implantation of coils after stent placement remains experimental. Testing of these new methods requires an animal model which imitates human aneurysms in size, configuration and neck morphology. We assessed in detail the technical requirements of and steps for transfemoral stent treatment of experimentally induced aneurysms at the top of the brachiocephalic trunk in rabbits. We created aneurysms in ten rabbits by distal ligation and intraluminal digestion of the right common carotid artery with elastase. We treated five animals with porous stents alone, and five with stents plus coiling via the meshes of the stent, which permitted dense packing of coils. No complications related to the procedures occurred. In all animals, even in those treated solely with porous stents, total occlusion of the aneurysm was achieved. Our animal model can be suitable for testing the biocompatibility and occlusion rate of new methods and devices for the treatment of experimental aneurysms. (orig.)

  11. Nickel and molybdenum contact allergies in patients with coronary in-stent restenosis.

    Science.gov (United States)

    Köster, R; Vieluf, D; Kiehn, M; Sommerauer, M; Kähler, J; Baldus, S; Meinertz, T; Hamm, C W

    2000-12-02

    Coronary in-stent restenosis might be triggered by contact allergy to nickel, chromate, or molybdenum ions released from stainless-steel stents. We investigated the association between allergic reactions to stent components and the occurrence of in-stent restenosis. Patients with coronary stainless-steel stents who underwent angiography for suspected restenosis were consecutively included in this study. Quantitative coronary angiography for analysis of percentage diameter stenosis was done on 131 patients (mean age 62 years [SD 9]) with 171 stents 6.1 months (2.7) after stent implantation. All patients underwent epicutaneous patch tests (Finn chamber method) for nickel, chromate, molybdenum, manganese, and small 316L stainless-steel plates. Patch tests were assessed by independent dermatologists after 48 h, 72 h, and when necessary 96 h of contact with the potential allergen. In-stent restenosis (> or =550% diameter stenosis) occurred in 89 patients. All ten patients with positive patch-test results had restenoses (p=0.03). Four male patients had positive reactions to molybdenum, and seven patients (four male, three female) had reactions to nickel. No patient with an allergic reaction to the standard test substances had a positive reaction to the stainless-steel plates. All patients with positive results had recurrent angina pectoris and needed target-vessel revascularisation. Patients with allergic patch-test reactions to nickel and molybdenum had a higher frequency of in-stent restenoses than patients without hypersensitivity. Allergic reactions to nickel and molybdenum released from stents may be one of the triggering mechanisms for in-stent restenosis.

  12. 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.

  13. Chemico-physical characterisation and in vivo biocompatibility assessment of DLC-coated coronary stents.

    Science.gov (United States)

    Castellino, Micaela; Stolojan, Vlad; Virga, Alessandro; Rovere, Massimo; Cabiale, Karine; Galloni, Marco R; Tagliaferro, Alberto

    2013-01-01

    The vast majority of stent thrombosis occurs in the acute and sub-acute phases and is more common in patients with acute coronary syndromes, due to the thrombotic milieu where stent struts are positioned. Stent thrombosis is likely due to incomplete tissue coverage of metallic stents as the contact between metallic stents and blood elements may lead to platelet adhesion and trigger vessel thrombosis. If a stent is covered after 7 days, the risk that it will be found uncovered at later stages is very low (DLC) coatings, deposited by physical vapour deposition, promote rapid endothelisation of coronary stent devices, with very low platelets activation, reducing thrombotic clots. We relate these behaviours to the surface and bulk material properties of the DLC films, subjected to a comprehensive chemico-physical characterisation using several techniques (X-ray photoelectron spectroscopy, atomic force microscopy, field-emission scanning electron microscope, transmission electron microscopy combined with electron energy loss spectroscopy, Raman and dispersive X-ray spectroscopy). In vivo studies, conducted on 24 pigs, have shown complete endothelisation after 7 days, with no fibrin mesh and with only rare monocytes scattered on the endothelial layer while 30 and 180 days tests have shown reduced inflammatory activation and a complete stabilisation of the vessel healing, with a minimal neointimal proliferation. The integral and permanent DLC film coating improves haemo- and bio-compatibility and leads to an excellent early vessel healing of the stent whilst the extremely thin strut thickness reduces the amount of late neointima and consequently the risk of late restenosis. These data should translate into a reduced acute and sub-acute stent thrombosis.

  14. Hemolytic effect of deformed intra-arterial stents and stent grafts in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Grimm, Jan; Brunn, Hinrich; Heller, Martin; Mueller-Huelsbeck, Stefan [Klinik fuer Diagnostische Radiologie der Christian-Albrecht-Universitaet (CAU) zu Kiel, A. Heller Strasse 9, 24105 Kiel (Germany)

    2003-06-01

    Our objective was to evaluate the hemolytic effect of stents and stent grafts in an in vitro flow model. The model consisted of silicone tubings. Pulsatile flow was delivered at 1170 ml/min. Diluted packed erythrocytes were used (hematocrit of 33%). The Palmaz, MegaLink stents or Passager, Hemobahn stent grafts were placed in the middle portion of the model; control experiments contained no implant (n=10 each). Concentric stenosis of the implant was achieved by constricting the implant to 25, 50, or 70% (area, n=10 each). Samples were drawn at minute 1, 2, 4, 6, 8, 10, 15, and every 10 min up to 1 h. Hemolytic parameters were evaluated. All implants produced hemolysis, increasing in the course of time. Without deformation (0%) the Hemobahn stent causes less hemolysis compared with the other prostheses. At 25% no significant difference could be shown between all devices. At 50% constriction the Palmaz stent caused more hemolysis than the other grafts, and at 70% stenosis the Palmaz and Hemobahn caused more hemolysis than Passager or Megalink. A hemolytic effect was evaluable, probably due to mechanical stress and sheer forces, induced by turbulences in the proximity of the deformed stent. The stent grafts did not perform better than the stents. Differences in the design of a prosthesis and in the degree of stent deformation seem to have an influence on the hemolysis caused. (orig.)

  15. Bronchial stents

    Directory of Open Access Journals (Sweden)

    Ibrahim Emad

    2006-01-01

    Full Text Available Bronchial stents are mostly used as a Palliative relief of symptoms often caused by airway obstruction, It is also used for sealing of stump fistulas after pneumonectomy and dehiscence after bronchoplastic operations. Advances in airway prosthetics have provided a variety of silicone stents, expandable metal stents, and pneumatic dilators, enabling the correction of increasingly complex anatomical problems. Several series have been published describing the application and results of these techniques. This manuscript reviews the historical development of stents, types, indication, outcome, and complications. Alternative therapies for tracheobronchial stenting were also reviewed

  16. In-Vitro Evaluation of Coronary Stents and 64-Detector-Row Computed Tomography Using a Newly Developed Model of Coronary Artery Stenosis

    International Nuclear Information System (INIS)

    Schlosser, T.; Scheuermann, T.; Ulzheimer, S.; Mohrs, O.K.; Kuehling, M.; Al brecht, P.E.; Voigtlaender, T.; Barkhausen, J.; Schmermund, A.

    2008-01-01

    Background: Stent implantation is the predominant therapy for non-surgical myocardial revascularization in patients with coronary artery disease. However, despite substantial advances in multidetector computed tomography (MDCT) coronary imaging, a reliable detection of coronary in-stent restenosis is currently not possible. Purpose: To examine the ability of 64-detector-row CT to detect and to grade in-stent stenosis in coronary stents using a newly developed ex-vivo vessel phantom with a realistic CT density pattern, artificial stenosis, and a thorax phantom. Material and Methods: Four different stents (Liberte and Lunar ROX, Boston Scientific; Driver, Medtronic; Multi-Link Vision, Guidant) were examined. The stents were placed on a polymer tube with a diameter of 2.5, 3.0, 3.5, or 4.0 mm. Different degrees of stenosis (0%, 30%, 50%, 70-80%) were created inside the tube. For quantitative analysis, attenuation values were measured in the non-stenotic vessel outside the stent, in the non-stenotic vessel inside the stent, and in the stenotic area inside the stent. The grade of stenosis was visually assessed by two observers. Results: All stents led to artificial reduction of attenuation, the least degree of which was found in the Liberte stent (11.3±10.2 HU) and the Multi-Link Vision stent (17.6±17.9 HU; P 0.25). Overall, the non-stenotic vessel was correctly diagnosed in 55.5%, the low-grade stenosis in 58.3%, the intermediate stenosis in 63.8%, and the high-grade stenosis in 80.5%. In the 3.0-, 3.5-, and 4.0-mm vessels, in none of the cases was a non-stenotic or low-grade stenotic vessel misdiagnosed as intermediate or high-grade stenosis. The average deviation from the real grade of stenosis was 0.40 for the Liberte stent, 0.46 for the Lunar ROX stent, 0.45 for the Driver stent, and 0.58 for the Multi-Link Vision stent. Conclusion: Our ex-vivo data show that non-stenotic stents and low-grade in-stent stenosis can be reliably differentiated from intermediate and

  17. The evaluation of primary stenting of sirolimus-eluting versus bare-metal stents in the treatment of atherosclerotic lesions of crural arteries

    International Nuclear Information System (INIS)

    Falkowski, Aleksander; Wilk, Grazyna; Poncyljusz, Wojciech; Szczerbo-Trojanowska, Malgorzata

    2009-01-01

    A comparison was made of sirolimus-eluting stents and bare stents as an effective means of treatment of stenosis in crural arteries. Patients were randomly divided into two groups: (1) patients treated with sirolimus-eluting stents and (2) patients treated with bare stents. Each group consisted of 25 patients, and every patient had one stent implanted. All patients showed symptoms of ischemia of the peripheral arteries, classified according to the Rutherford scale into categories 3, 4, and 5. All patients were examined 24 h before and 24 h and 6 months after the intervention. The results were analyzed according to clinical, hemodynamic, and angiographic criteria. Technically, the procedure was successful in 100% of cases, and both groups presented an equal improvement in clinical and hemodynamic parameters. The follow-up angiographic examination demonstrated a significantly lower rate of restenosis among the sirolimus-eluting stent group (4, 16%) versus the bare stent group (19, 76%) (p < 0.001), with lower target lesion revascularization in 3 (12%) versus 14 (56%) (p < 0.05), respectively. Quantitative angiography demonstrated that all variables used to assess restenosis were superior for sirolimus-eluting stents 6 months after intervention: late lumen loss 0.46 ± 0.72 versus 1.70 ± 0.94 (p < 0.001) and minimal lumen diameter 2.25 ± 0.82 versus 0.99 ± 1.08 (p < 0.001). Results of this study reveal that the use of sirolimus-eluting stents decreases the risk of restenosis in comparison to standard stents. (orig.)

  18. The evaluation of primary stenting of sirolimus-eluting versus bare-metal stents in the treatment of atherosclerotic lesions of crural arteries

    Energy Technology Data Exchange (ETDEWEB)

    Falkowski, Aleksander; Wilk, Grazyna [Pomeranian Medical University of Szczecin, Departament of General and Dental Diagnostic Imaging, Szczecin (Poland); Poncyljusz, Wojciech [Pomeranian Medical University of Szczecin, Departament of Diagnostic Imaging and Interventional Radiology, Szczecin (Poland); Szczerbo-Trojanowska, Malgorzata [Medical University of Lublin, Department of Interventional Radiology and Neuroradiology, Lublin (Poland)

    2009-04-15

    A comparison was made of sirolimus-eluting stents and bare stents as an effective means of treatment of stenosis in crural arteries. Patients were randomly divided into two groups: (1) patients treated with sirolimus-eluting stents and (2) patients treated with bare stents. Each group consisted of 25 patients, and every patient had one stent implanted. All patients showed symptoms of ischemia of the peripheral arteries, classified according to the Rutherford scale into categories 3, 4, and 5. All patients were examined 24 h before and 24 h and 6 months after the intervention. The results were analyzed according to clinical, hemodynamic, and angiographic criteria. Technically, the procedure was successful in 100% of cases, and both groups presented an equal improvement in clinical and hemodynamic parameters. The follow-up angiographic examination demonstrated a significantly lower rate of restenosis among the sirolimus-eluting stent group (4, 16%) versus the bare stent group (19, 76%) (p < 0.001), with lower target lesion revascularization in 3 (12%) versus 14 (56%) (p < 0.05), respectively. Quantitative angiography demonstrated that all variables used to assess restenosis were superior for sirolimus-eluting stents 6 months after intervention: late lumen loss 0.46 {+-} 0.72 versus 1.70 {+-} 0.94 (p < 0.001) and minimal lumen diameter 2.25 {+-} 0.82 versus 0.99 {+-} 1.08 (p < 0.001). Results of this study reveal that the use of sirolimus-eluting stents decreases the risk of restenosis in comparison to standard stents. (orig.)

  19. Does intravascular ultrasound provide clinical benefits for percutaneous coronary intervention with bare-metal stent implantation? A meta-analysis of randomized controlled trials

    Directory of Open Access Journals (Sweden)

    Lodi-Junqueira Lucas

    2012-09-01

    Full Text Available Abstract Background The role of intravascular ultrasound (IVUS in percutaneous coronary interventions (PCI is still controversial despite several previously published meta-analyses. A meta-analysis to evaluate the controversial role of IVUS-guided PCI with bare-metal stenting was performed and a previous published meta-analysis was re-evaluated in order to clarify the discrepancy between results of these studies. Methods A systematic review was performed by an electronic search of the PubMed, Embase and Web of Knowledge databases and by a manual search of reference lists for randomized controlled trials published until April 2011, with clinical outcomes and, at least, six months of clinical follow-up. A meta-analysis based on the intention to treat was performed with the selected studies. Results Five studies and 1,754 patients were included. There were no differences in death (OR = 1.86; 95% CI = 0.88-3.95; p = 0.10, non-fatal myocardial infarction (OR = 0.65; 95% CI = 0.27-1.58; p = 0.35 and major adverse cardiac events (OR = 0.74; 95% CI = 0.49-1.13; p = 0.16. An analysis of the previous published meta-analysis strongly suggested the presence of publication bias. Conclusions There is no evidence to recommend routine IVUS-guided PCI with bare-metal stent implantation. This may be explained by the paucity and heterogeneity of the studies published so far.

  20. An Assessment of Radiologically Inserted Transoral and Transgastric Gastroduodenal Stents to Treat Malignant Gastric Outlet Obstruction

    Energy Technology Data Exchange (ETDEWEB)

    Miller, Bethany H. T., E-mail: bmiller@doctors.org.uk [Lancashire Teaching Hospitals NHS Foundation Trust, Royal Preston Hospital, Department of Upper Gastrointestinal Surgery (United Kingdom); Griffiths, Ewen A., E-mail: Eagriffiths@doctors.org.uk [The New Queen Elizabeth Hospital, Department of Upper Gastrointestinal Surgery (United Kingdom); Pursnani, Kishore G., E-mail: Kish.Pursnani@lthtr.nhs.uk; Ward, Jeremy B., E-mail: Jeremy.Ward@lthtr.nhs.uk [Lancashire Teaching Hospitals NHS Foundation Trust, Royal Preston Hospital, Department of Upper Gastrointestinal Surgery (United Kingdom); Stockwell, Robert C., E-mail: Robert.Stockwell@lthtr.nhs.uk [Lancashire Teaching Hospitals NHS Foundation Trust, Chorley and South Ribble Hospital, Department of Radiology (United Kingdom)

    2013-12-15

    IntroductionSelf-expanding metallic stents (SEMS) are used to palliate malignant gastric outlet obstruction (GOO) and are useful in patients with limited life expectancy or severe medical comorbidity, which would preclude surgery. Stenting can be performed transorally or by a percutaneous transgastric technique. Our goal was to review the outcome of patients who underwent radiological SEMS insertion performed by a single consultant interventional radiologist. Methods: Patients were identified from a prospectively collected database held by one consultant radiologist. Data were retrieved from radiological reports, multidisciplinary team meetings, and the patients' case notes. Univariate survival analysis was performed. Results: Between December 2000 and January 2011, 100 patients (63 males, 37 females) had 110 gastroduodenal stenting procedures. Median age was 73 (range 39-89) years. SEMS were inserted transorally (n = 66) or transgastrically (n = 44). Site of obstruction was the stomach (n = 37), duodenum (n = 50), gastric pull-up (n = 10), or gastroenterostomy (n = 13). Seven patients required biliary stents. Technical success was 86.4 %: 83.3 % for transoral insertion, 90.9 % for transgastric insertion. Eleven patients developed complications. Median GOO severity score: 1 pre-stenting, 2 post-stenting (p = 0.0001). Median survival was 54 (range 1-624) days. Post-stenting GOO severity score was predictive of survival (p = 0.0001). Conclusions: The technical success rate for insertion of palliative SEMS is high. Insertional technique can be tailored to the individual depending on the location of the tumor and whether it is possible to access the stomach percutaneously. Patients who have successful stenting and return to eating a soft/normal diet have a statistically significant increase in survival.

  1. An assessment of radiologically inserted transoral and transgastric gastroduodenal stents to treat malignant gastric outlet obstruction.

    Science.gov (United States)

    Miller, Bethany H T; Griffiths, Ewen A; Pursnani, Kishore G; Ward, Jeremy B; Stockwell, Robert C

    2013-12-01

    Self-expanding metallic stents (SEMS) are used to palliate malignant gastric outlet obstruction (GOO) and are useful in patients with limited life expectancy or severe medical comorbidity, which would preclude surgery. Stenting can be performed transorally or by a percutaneous transgastric technique. Our goal was to review the outcome of patients who underwent radiological SEMS insertion performed by a single consultant interventional radiologist. Patients were identified from a prospectively collected database held by one consultant radiologist. Data were retrieved from radiological reports, multidisciplinary team meetings, and the patients' case notes. Univariate survival analysis was performed. Between December 2000 and January 2011, 100 patients (63 males, 37 females) had 110 gastroduodenal stenting procedures. Median age was 73 (range 39-89) years. SEMS were inserted transorally (n = 66) or transgastrically (n = 44). Site of obstruction was the stomach (n = 37), duodenum (n = 50), gastric pull-up (n = 10), or gastroenterostomy (n = 13). Seven patients required biliary stents. Technical success was 86.4 %: 83.3 % for transoral insertion, 90.9 % for transgastric insertion. Eleven patients developed complications. Median GOO severity score: 1 pre-stenting, 2 post-stenting (p = 0.0001). Median survival was 54 (range 1-624) days. Post-stenting GOO severity score was predictive of survival (p = 0.0001). The technical success rate for insertion of palliative SEMS is high. Insertional technique can be tailored to the individual depending on the location of the tumor and whether it is possible to access the stomach percutaneously. Patients who have successful stenting and return to eating a soft/normal diet have a statistically significant increase in survival.

  2. An Assessment of Radiologically Inserted Transoral and Transgastric Gastroduodenal Stents to Treat Malignant Gastric Outlet Obstruction

    International Nuclear Information System (INIS)

    Miller, Bethany H. T.; Griffiths, Ewen A.; Pursnani, Kishore G.; Ward, Jeremy B.; Stockwell, Robert C.

    2013-01-01

    IntroductionSelf-expanding metallic stents (SEMS) are used to palliate malignant gastric outlet obstruction (GOO) and are useful in patients with limited life expectancy or severe medical comorbidity, which would preclude surgery. Stenting can be performed transorally or by a percutaneous transgastric technique. Our goal was to review the outcome of patients who underwent radiological SEMS insertion performed by a single consultant interventional radiologist. Methods: Patients were identified from a prospectively collected database held by one consultant radiologist. Data were retrieved from radiological reports, multidisciplinary team meetings, and the patients’ case notes. Univariate survival analysis was performed. Results: Between December 2000 and January 2011, 100 patients (63 males, 37 females) had 110 gastroduodenal stenting procedures. Median age was 73 (range 39–89) years. SEMS were inserted transorally (n = 66) or transgastrically (n = 44). Site of obstruction was the stomach (n = 37), duodenum (n = 50), gastric pull-up (n = 10), or gastroenterostomy (n = 13). Seven patients required biliary stents. Technical success was 86.4 %: 83.3 % for transoral insertion, 90.9 % for transgastric insertion. Eleven patients developed complications. Median GOO severity score: 1 pre-stenting, 2 post-stenting (p = 0.0001). Median survival was 54 (range 1–624) days. Post-stenting GOO severity score was predictive of survival (p = 0.0001). Conclusions: The technical success rate for insertion of palliative SEMS is high. Insertional technique can be tailored to the individual depending on the location of the tumor and whether it is possible to access the stomach percutaneously. Patients who have successful stenting and return to eating a soft/normal diet have a statistically significant increase in survival

  3. Expansion and fixation properties of a new braided biodegradable urethral stent: an experimental study in the rabbit.

    Science.gov (United States)

    Vaajanen, Anu; Nuutinen, Juha-Pekka; Isotalo, Taina; Törmälä, Pertti; Tammela, Teuvo L J; Talja, Martti

    2003-03-01

    Biodegradable spiral urethral stents have been used with favorable results combined with thermal treatments of the prostate and for recurrent urethral strictures but the configuration of the helical spiral is not ideal. We developed a new tubular mesh configuration for the biodegradable urethral stent and evaluated its expansion and locking properties in the rabbit urethra. The stents were made of self-reinforced polylactic acid polymer (Bionx Implants, Ltd., Tampere, Finland) blended with BaSO (Alfa Chem, New York, New York) to achieve radiopacity. Two braiding patterns, that is 1 over 1 and 2 over 2 + 1, were used to produce a tubular mesh structure. Stainless steel stents (pattern 1 over 1) served as controls. The stents were inserted into the posterior urethra of 27 male rabbits. The animals were sacrificed after 1 week, 1 and 6 months, respectively. X-rays were done immediately after stent insertion and at sacrifice. Longitudinal movement and expansion were assessed on the x-rays.(4) All stents maintained position in the urethra without fixation. Macroscopic disorientation of the structure of the 2 over 2 + 1 braided self-reinforced polylactic acid polymer stents began before 1 month, while 1 over 1 braided stents retained their construction. At 6 months 3 of 6 biodegradable stents were degraded. Average longitudinal movement was 2 mm. (range 1 to 3) in the 1 over 1 self-reinforced polylactic acid polymer group, 2 mm. (range 0 to 7) in the 2 over 2 + 1 polylactic acid group and 3 mm. (range 3 to 3) in controls at 1 month. Biodegradable polymers are suitable materials for braided urethral stents. The expansion properties of the 2 braiding models tested in this study sufficed to fix the stents in situ in the prostatic urethra. However, the 1 over 1 braiding pattern was superior to the 2 over 2 + 1 pattern, in that it retained its macroscopic construction until the degradation of single self-reinforced polylactic acid polymer fibers.

  4. Pulsatility Index in Aortic Coarctation: A Possible Way to Evaluate Factors Affecting Stenting Outcome

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Keramati

    2012-03-01

    Full Text Available Background: The pulsatility index (PI shows continuous blood flow to the end organs and is a significant factor believed to decrease in aortic coarctation. Correction of this factor is of great importance in the treatment of stenotic lesions of the aorta. However, there are minimal data regarding the trend of changes in the PI after stent implantation. Furthermore, the association between the PI and other echocardiographic indices in patients undergoing stent implantation is unclear. This study was designed to evaluate changes in the PI following stenting and its correlation with other echocardiographic indices. Methods: Twenty-three patients with a diagnosis of aortic coarctation consecutively underwent two-dimensional and Doppler echocardiographic imaging modalities twice (before and after stenting. The patients were divided into two groups based on the percentage of increase in the PI after stenting ( < 50% or ≥ 50%. The relation between the post-stenting PI and the baseline echocardiographic indices was assessed. Results: The PI was increased from 0.89 (SD = 0.30 to 1.75 (SD = 0.51 after stenting (p value < 0.001. Baseline diastolic/systolic velocity (D/S velocity ratio of the abdominal aorta (p value = 0.013, mean velocity (p value = 0.033, and peak gradient of the descending aorta (p value = 0.033 were significantly higher in the patients with ≥ 50% increase in the PI after stenting. Conclusion: Our findings showed that elevation in the PI after stenting was a predictable criterion in patients with aortic coarctation: it was predicted by some baseline clinical and echocardiographic indices. Baseline D/S ratio velocity of the abdominal aorta, mean velocity and peak gradient of the descending aorta, and baseline systolic blood pressure were the statistically significant indices to predict ≥ 50% increase in the PI in our patients.

  5. Percutaneous coronary revascularization using a trilayer metal phosphorylcholine-coated zotarolimus-eluting stent.

    Science.gov (United States)

    Abizaid, Alexandre; Lansky, Alexandra J; Fitzgerald, Peter J; Tanajura, Luis Fernando; Feres, Fausto; Staico, Rodolfo; Mattos, Luiz; Abizaid, Andrea; Chaves, Aurea; Centemero, Marinella; Sousa, Amanda G M R; Sousa, J Eduardo; Zaugg, Margo J; Schwartz, Lewis B

    2007-05-15

    The ZoMaxx Coronary Stent System elutes the antiproliferative agent zotarolimus via a biocompatible phosphorylcholine polymer loaded onto a novel, thin, stainless steel stent platform containing an 0.0007-inch inner layer of tantalum that enhances fluoroscopic radiopacity. The objective of this single-arm prospective clinical trial was to assess the safety and performance of the ZoMaxx stent for the treatment of coronary artery stenosis. Forty consecutive patients with ischemic coronary occlusive disease due to single de novo obstructive lesions of native coronary arteries were treated with 3 x 18 mm ZoMaxx stents at the Dante Pazzanese de Cardiologie in Saõ Paulo, Brazil, between April and July 2005. Independent core laboratories analyzed quantitative coronary angiography and intravascular ultrasound results immediately after stent implantation, and after 4 months. The lesion, procedure, and device-deployment success rates were all 100% (40 of 40). There were no major adverse cardiac events during the study. Follow-up quantitative coronary angiography at 4 months revealed in-stent and in-segment late lumen losses of 0.20 +/- 0.35 and 0.17 +/- 0.35 mm, respectively. Follow-up intravascular ultrasound at 4 months revealed 6.5 +/- 6.2% neointimal volume obstruction. There were no instances of late acquired stent incomplete apposition or stent thrombosis. In conclusion, the ZoMaxx Coronary Stent can be safely implanted for the treatment of de novo coronary artery stenosis. The inhibition of neointima formation as measured by follow-up angiography and IVUS after 4 months suggests therapeutic potential for the reduction of restenosis.

  6. Electromechanical impedance method to assess dental implant stability

    Science.gov (United States)

    Tabrizi, Aydin; Rizzo, Piervincenzo; Ochs, Mark W.

    2012-11-01

    The stability of a dental implant is a prerequisite for supporting a load-bearing prosthesis and establishment of a functional bone-implant system. Reliable and noninvasive methods able to assess the bone interface of dental and orthopedic implants (osseointegration) are increasingly demanded for clinical diagnosis and direct prognosis. In this paper, we propose the electromechanical impedance method as a novel approach for the assessment of dental implant stability. Nobel Biocare® implants with a size of 4.3 mm diameter ×13 mm length were placed inside bovine bones that were then immersed in a solution of nitric acid to allow material degradation. The degradation simulated the inverse process of bone healing. The implant-bone systems were monitored by bonding a piezoceramic transducer (PZT) to the implants’ abutment and measuring the admittance of the PZT over time. It was found that the PZT’s admittance and the statistical features associated with its analysis are sensitive to the degradation of the bones and can be correlated to the loss of calcium measured by means of the atomic absorption spectroscopy method. The present study shows promising results and may pave the road towards an innovative approach for the noninvasive monitoring of dental implant stability and integrity.

  7. Impact of nitinol stent surface processing on in-vivo nickel release and biological response.

    Science.gov (United States)

    Nagaraja, Srinidhi; Sullivan, Stacey J L; Stafford, Philip R; Lucas, Anne D; Malkin, Elon

    2018-03-27

    this knowledge gap by implanting single and overlapped nitinol stents with different surface finishes to assess systemic impact on minipigs (i.e. serum and urine nickel levels, liver and kidney function, immune and blood count) over the 6 month implantation period. In addition, nickel levels and histopathology in stented arteries were analyzed on explant to determine relationships between surface processing and local adverse tissue reactions. The findings presented here highlight the importance of surface processing on in-vivo nickel release and subsequent impact on local biological response for nitinol implants. Published by Elsevier Ltd.

  8. A bioresorbable urethral stent. An experimental study.

    Science.gov (United States)

    Kemppainen, E; Talja, M; Riihelä, M; Pohjonen, T; Törmälä, P; Alfthan, O

    1993-05-01

    The aim of the present study was to examine the suitability of biodegradable polymers as materials for a urethral stent. A new urethral stent made of biodegradable self-reinforced poly-L-lactide (SR-PLLA) was implanted in 16 male rabbits after urethrotomy. Seven stents of stainless steel served as controls. The dimensions of the two types of stents were identical: length 15 mm, diameter 8.2 mm. The mechanical construction was a helical spiral. The SR-PLLA spiral was sustained with three microspirals, and the whole device was coated with DL-lactide to achieve an active initial tissue reaction and better tissue penetration. The SR-PLLA stent showed more favourable implantation properties than the steel one. Within 6 months all PLLA stents had implanted, and the tissue reaction around the stent material was minimal. The helical spiral of stainless steel induced a remarkable inflammatory reaction due to poor implantation properties. We suggest that biodegradable SR-PLLA is a promising material for a urethral stent to prevent re-stenosis of urethral strictures.

  9. Biocompatibility and implantation properties of 2 differently braided, biodegradable, self-reinforced polylactic acid urethral stents: an experimental study in the rabbit.

    Science.gov (United States)

    Isotalo, Taina; Nuutinen, Juha-Pekka; Vaajanen, Anu; Martikainen, Paula M; Laurila, Marita; Törmälä, Pertti; Talja, Martti; Tammela, Teuvo L J

    2005-12-01

    Biodegradable urethral stents have been in clinical use for more than 10 years. To solve the problems connected with the helical spiral configuration of the stents used to date we developed a new tubular mesh configuration and evaluated the biocompatibility properties and degradation time of 2 differently braided stents in the rabbit urethra. The biodegradable, self-expanding stents were made of self-reinforced polylactic acid polymer blended with BaSO4 (Alfa Chem, Kings Point, New York). Two braiding patterns, namely a diamond 1/1 and a regular 2/2 + 1 (Prodesco, Perkasie, Pennsylvania), were used to produce a tubular mesh configuration. Stainless steel stents with 1/1 braiding served as controls. The stents were inserted into the posterior urethra of 36 male rabbits. The animals were sacrificed after 1 week, 1 month, 6 months or 12 months. Light microscopy and scanning electron microscopy analyses were done. Tissue reactions to operative trauma were seen in all specimens at week 1. The changes gradually abated in the biodegradable stent groups, whereas chronic inflammatory changes and fibrosis were increasingly seen with metallic stents after 6 months. Epithelial hyperplasia increased with time for all stent types and materials. As expected, stent fragmentation started at 6 months. Biodegradable polymers are suitable materials for braided urethral stents. However, the braided configuration of the stent with a decreased mass of material does not prevent the development of epithelial hyperplasia. The biodegradable, self-expanding, braided stents functioned well in the rabbit urethra and are suitable for clinical studies.

  10. Implante de stents en ramas de arterias pulmonares en cardiopatías congénitas: experiencia multicéntrica de 10 años

    Directory of Open Access Journals (Sweden)

    Alejandro Peirone

    2016-01-01

    Full Text Available Introducción: La angioplastia con implante de stent se considera el tratamiento de elección para la mayoría de los casos de estenosis congénita o adquirida posquirúrgica de ramas de arterias pulmonares en pacientes portadores de cardiopatías congénitas. Sin embargo, aún persisten dudas sobre la efectividad clínica y la incidencia de complicaciones de esta técnica que necesitan ser esclarecidas. Material y métodos: Estudio multicéntrico descriptivo, retrospectivo, observacional. Los procedimientos se realizaron desde enero de 2005 hasta abril de 2015. Un total 25 pacientes fueron sometidos a angioplastia con implante de stent en ramas de arterias pulmonares, los cuales fueron seguidos evolutivamente en su estado clínico y por diferentes métodos de imágenes. Se definió buena efectividad clínica al mejoramiento clínico sintomático y/o anatómico persistente del paciente intervenido. Resultados: La cohorte de 25 pacientes tenía una edad promedio de 9,48 años (2 meses-34 años, un peso promedio de 27,54 kg (3-104 y el 44% era de sexo femenino. Las cardiopatías congénitas de base intervenidas fueron en su mayoría tetralogía de Fallot y sus variantes, seguida por corazones con fisiología univentricular poscirugías de Glenn bidireccional y/o de FontanKreutzer. La presión sistólica del ventrículo derecho y de la arteria pulmonar disminuyeron significativamente posintervención (de 68,35 mm Hg a 45,8 mm Hg y de 47,4 mm Hg a 32,08 mm Hg, respectivamente (p < 0,0001. El diámetro mínimo de la lesión a tratar se incrementó significativamente posprocedimiento (de 3,98 mm a 9,82 mm; p < 0,0001. La incidencia de complicaciones fue del 8% (2 pacientes y se registró buena efectividad clínica en 22 pacientes (88%. Conclusiones: La angioplastia con colocación de stent en las ramas de arterias pulmonares resultó una técnica segura y eficaz, aunque desafiante, con una marcada mejoría clínica y anatómica de las lesiones

  11. Nanophasic biodegradation enhances the durability and biocompatibility of magnesium alloys for the next-generation vascular stents

    Science.gov (United States)

    Mao, Lin; Shen, Li; Niu, Jialin; Zhang, Jian; Ding, Wenjiang; Wu, Yu; Fan, Rong; Yuan, Guangyin

    2013-09-01

    Biodegradable metal alloys emerge as a new class of biomaterials for tissue engineering and medical devices such as cardiovascular stents. Deploying biodegradable materials to fabricate stents not only obviates a second surgical intervention for implant removal but also circumvents the long-term foreign body effect of permanent implants. However, these materials for stents suffer from an un-controlled degradation rate, acute toxic responses, and rapid structural failure presumably due to a non-uniform, fast corrosion process. Here we report that highly uniform, nanophasic degradation is achieved in a new Mg alloy with unique interstitial alloying composition as the nominal formula Mg-2.5Nd-0.2Zn-0.4Zr (wt%, hereafter, denoted as JDBM). This material exhibits highly homogeneous nanophasic biodegradation patterns as compared to other biodegradable metal alloy materials. Consequently it has significantly reduced degradation rate determined by electrochemical characterization. The in vitro cytotoxicity test using human vascular endothelial cells indicates excellent biocompatibility and potentially minimal toxic effect on arterial vessel walls. Finally, we fabricated a cardiovascular stent using JDBM and performed in vivo long-term assessment via implantation of this stent in an animal model. The results confirmed the reduced degradation rate in vivo, excellent tissue compatibility and long-term structural and mechanical durability. Thus, this new Mg-alloy with highly uniform nanophasic biodegradation represents a major breakthrough in the field and a promising material for manufacturing the next generation biodegradable vascular stents.

  12. Electromechanical impedance method to assess dental implant stability

    International Nuclear Information System (INIS)

    Tabrizi, Aydin; Rizzo, Piervincenzo; Ochs, Mark W

    2012-01-01

    The stability of a dental implant is a prerequisite for supporting a load-bearing prosthesis and establishment of a functional bone–implant system. Reliable and noninvasive methods able to assess the bone interface of dental and orthopedic implants (osseointegration) are increasingly demanded for clinical diagnosis and direct prognosis. In this paper, we propose the electromechanical impedance method as a novel approach for the assessment of dental implant stability. Nobel Biocare ® implants with a size of 4.3 mm diameter ×13 mm length were placed inside bovine bones that were then immersed in a solution of nitric acid to allow material degradation. The degradation simulated the inverse process of bone healing. The implant–bone systems were monitored by bonding a piezoceramic transducer (PZT) to the implants’ abutment and measuring the admittance of the PZT over time. It was found that the PZT’s admittance and the statistical features associated with its analysis are sensitive to the degradation of the bones and can be correlated to the loss of calcium measured by means of the atomic absorption spectroscopy method. The present study shows promising results and may pave the road towards an innovative approach for the noninvasive monitoring of dental implant stability and integrity. (paper)

  13. 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

  14. Transient Euler-Lagrange/DEM simulation of stent thrombosis

    Directory of Open Access Journals (Sweden)

    Stiehm Michael

    2016-09-01

    Full Text Available Stent implantation is the treatment of choice for cardiovascular diseases. By introduction of biodegradable thick strut stents investigations of thrombosis formation is one focus of research. This study deals with a transient Euler-Lagrange/DEM approach to simulate the flow field, platelet movement and clotting. The recirculation zones prolong particle residence time. As a result, the vicinity of stent struts shown a particularly higher risk for stent thrombosis.

  15. Polydioxanone biodegradable stent placement in a canine urethral model: analysis of inflammatory reaction and biodegradation.

    Science.gov (United States)

    Park, Jung-Hoon; Song, Ho-Young; Shin, Ji Hoon; Kim, Jin Hyoung; Jun, Eun Jung; Cho, Young Chul; Kim, Soo Hwan; Park, Jihong

    2014-08-01

    To investigate the inflammatory reaction and perform quantitative analysis of biodegradation after placement of a polydioxanone (PDO) biodegradable stent in a canine urethral model. PDO biodegradable stents were placed in the proximal and distal urethra of nine male mongrel dogs. The dogs were euthanized 4 weeks (group A; n = 3), 8 weeks (group B; n = 3), or 12 weeks (group C; n = 3) after stent placement. The luminal diameter of the stent-implanted urethra was assessed by follow-up retrograde urethrography, and histologic findings were obtained after the dogs were killed. Stents were removed after euthanasia, and their surface morphology and molecular weight were evaluated. Hematologic examination was performed to evaluate inflammatory reaction. Stent placement was technically successful in all dogs. The average luminal diameter gradually decreased. The average number of epithelial layers (2.93 vs 4.42; P stents were completely decomposed. An experimental study in a canine urethral model has demonstrated acceptable inflammatory reaction with gradually increasing granulation tissue but no luminal obstruction within 12 weeks. Copyright © 2014 SIR. Published by Elsevier Inc. All rights reserved.

  16. Long-term prognostic value of risk scores after drug-eluting stent implantation for unprotected left main coronary artery: A pooled analysis of the ISAR-LEFT-MAIN and ISAR-LEFT-MAIN 2 randomized clinical trials.

    Science.gov (United States)

    Xhepa, Erion; Tada, Tomohisa; Kufner, Sebastian; Ndrepepa, Gjin; Byrne, Robert A; Kreutzer, Johanna; Ibrahim, Tareq; Tiroch, Klaus; Valgimigli, Marco; Tölg, Ralf; Cassese, Salvatore; Fusaro, Massimiliano; Schunkert, Heribert; Laugwitz, Karl L; Mehilli, Julinda; Kastrati, Adnan

    2017-01-01

    To evaluate the long-term prognostic value of risk scores in the setting of drug-eluting stent (DES) implantation for uLMCA. Data on the prognostic value of novel risk scores developed to select the most appropriate revascularization strategy in patients undergoing DES implantation for uLMCA disease are relatively limited. The study represents a patient-level pooled analysis of the ISAR-LEFT-MAIN (607 patients randomized to paclitaxel-eluting or sirolimus-eluting stents) and the ISAR-LEFT-MAIN-2 (650 patients randomized to everolimus-eluting or zotarolimus-eluting stents) randomized trials. The Syntax Score (SxScore) as well the Syntax Score II (SS-II), the EuroSCORE and the Global Risk Classification (GRC) were calculated. The primary outcome was all-cause mortality. At a mean follow-up of 3 years there were 160 deaths (12.7%). The death-incidence was significantly higher in the upper tertiles than in the intermediate or lower ones for all risk scores (log-rank test P risk scores were able to stratify the mortality risk at long-term follow-up. EuroSCORE was the only risk score that significantly improved the discriminatory power of a multivariable model to predict long-term mortality. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  17. 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

  18. Outcomes of ≤6-month versus 12-month dual antiplatelet therapy after drug-eluting stent implantation

    Science.gov (United States)

    Villablanca, Pedro A.; Massera, Daniele; Mathew, Verghese; Bangalore, Sripal; Christia, Panagiota; Perez, Irving; Wan, Ningxin; Schulz-Schüpke, Stefanie; Briceno, David F.; Bortnick, Anna E.; Garcia, Mario J.; Lucariello, Richard; Menegus, Mark; Pyo, Robert; Wiley, Jose; Ramakrishna, Harish

    2016-01-01

    Abstract Background: The benefit of ≤6-month compared with 12-month dual antiplatelet therapy (DAPT) after percutaneous coronary intervention (PCI) with drug-eluting stent (DES) placement remains controversial. We performed a meta-analysis and meta-regression of ≤6-month versus 12-month DAPT in patients undergoing PCI with DES placement. Methods: We conducted electronic database searches of randomized controlled trials (RCTs) comparing DAPT durations after DES placement. For studies with longer follow-up, outcomes at 12 months were identified. Odds ratios and 95% confidence intervals were computed with the Mantel–Haenszel method. Fixed-effect models were used; if heterogeneity (I2) > 40 was identified, effects were obtained with random models. Results: Nine RCTs were included with total n = 19,224 patients. No significant differences were observed between ≤6-month compared with 12-month DAPT in all-cause mortality (OR 0.87; 95% confidence interval (CI): 0.69–1.11), cardiovascular (CV) mortality (OR 0.89; 95% CI: 0.66–1.21), non-CV mortality (OR 0.85; 95% 0.58–1.24), myocardial infarction (OR 1.10; 95% CI: 0.89–1.37), stroke (OR 0.97; 95% CI: 0.67–1.42), stent thrombosis (ST) (OR 1.37; 95% CI: 0.89–2.10), and target vessel revascularization (OR 0.95; 95% CI: 0.77–1.18). No significant difference in major bleeding (OR 0.72; 95% CI: 0.49–1.05) was observed, though the all-bleeding event rate was significantly lower in the ≤6-month DAPT group (OR 0.76; 95% CI: 0.59–0.96). In the meta-regression analysis, a significant association between bleeding events and non-CV mortality with 12-month DAPT was found, as well as between ST and mortality in addition to MI with ≤6-month DAPT. Conclusion: DAPT for ≤6 months is associated with similar mortality and ischemic outcomes but less bleeding events compared with 12-month DAPT after PCI with DES. PMID:28033306

  19. 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....

  20. Neointima development in externally stented saphenous vein grafts

    Directory of Open Access Journals (Sweden)

    Przemysław Węglarz

    2016-11-01

    Full Text Available Introduction : The main limitation of coronary artery bypass grafting (CABG is rapid neointimal hyperplasia leading to graft failure. Aim : To assess plaque formation in saphenous vein grafts (SVG covered by an external Dacron stent in comparison with the classical technique. Material and methods : In the study group vein grafts covered by external stent mesh made of Dacron were implanted. An intravascular ultrasonography (IVUS study was performed in 35 aorto-coronary SVG covered by an external Dacron stent and in 64 normal SVG during the first year after CABG. In each SVG 25 mm of good quality IVUS image, volumes of lumen, plaque (neointima, outer border of the vein graft (external SVG and adventitia were calculated in three time periods: 0–130 days, 130–260 days and 260–390 days. Results : Between the first and second time period, lumen volume (mm3 was reduced from 10.33 ±4.4, to 6.80 ±2.23 in the second period and 5.69 ±1.26 in the third one. This effect was much less marked in normal grafts. The corresponding lumen volume (mm3 was: 10.90 ±3.9, 9.15 ±2.94 and 8.92 ±2.93 in consecutive time periods. Plaque volume (mm3 did not change in control grafts during the course of the study, but it increased very significantly in stented grafts from 0.86 ±1.24 in the first period to 2.70 ±1.58 in the second and 3.29 ±2.66 in the third one. Conclusions : The experimental technique of implanting SVG covered with an external elastic Dacron stent seems to be inferior to traditional ones. This is probably due to the more complicated process of vein implantation and higher micro-injury occurrence during the surgery.

  1. Comparison of outcomes after everolimus-eluting stent implantation in diabetic versus non-diabetic patients in the Tokyo-MD PCI study.

    Science.gov (United States)

    Konishi, Yuji; Ashikaga, Takashi; Sasaoka, Taro; Kurihara, Ken; Yoshikawa, Syunji; Isobe, Mitsuaki

    2016-03-01

    Diabetes mellitus (DM), especially in those requiring insulin for treatment, is known to be a risk factor for adverse events after percutaneous coronary intervention using first-generation drug-eluting stents. However, the role of DM in patients treated with everolimus-eluting stents (EES) is less known. The purpose of the present analysis was to evaluate the outcomes of treatment with EES for DM patients both requiring and not requiring insulin, and to compare them with non-DM patients. Of patients treated with EES in the Tokyo-MD PCI study, an all-comer, multicenter, observational cohort study, we identified 199 insulin-requiring diabetics (IRDM), 575 non-insulin requiring diabetics (NIRDM), and 1092 non-diabetics (non-DM). The main outcomes were major adverse cardiovascular events (MACE) defined as a composite of all-cause death, myocardial infarction, and stroke, and target lesion revascularization (TLR). The cumulative incidence of MACE and TLR was significantly greater in patients with IRDM than non-DM [MACE: hazard ratio 1.97, 95% confidence interval (CI) 1.31-2.90, p<0.01; TLR: hazard ratio 3.43, 2.07-5.55, p<0.0001] according to univariate Cox proportional hazards model. After adjusting for confounders using the multivariate Cox proportional hazard model, the risk of IRDM versus non-DM for TLR remained significant (hazard ratio 1.92, 1.10-3.29, p=0.02). The incidence of TLR in NIRDM was slightly greater than that in non-DM according to univariate analysis (hazard ratio 1.65, 1.07-2.54, p=0.02). However, the risk was not statistically different in the multivariate analysis (hazard ratio 1.52, 0.97-2.35, p=0.06). In this all-comer, observational study, the risk of TLR was greater in IRDM compared with non-DM after EES implantation, while the increased risk for TLR from NIRDM did not reach statistical significance. Copyright © 2015 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.

  2. Anatomical and functional assessment of Tryton bifurcation stent before and after final kissing balloon dilatation: Evaluations by three-dimensional coronary angiography, optical coherence tomography imaging and fractional flow reserve.

    Science.gov (United States)

    Pyxaras, Stylianos A; Toth, Gabor G; Di Gioia, Giuseppe; Ughi, Giovanni J; Tu, Shengxian; Rusinaru, Dan; Adriaenssens, Tom; Reiber, Johan H C; Leon, Martin B; Bax, Jeroen J; Wijns, William

    2017-07-01

    To assess the anatomical and functional impact of final kissing balloon inflation (FKBI) after implantation of a dedicated bifurcation stent system. Current evidence suggests clinical benefit of FKBI in patients undergoing bifurcation dilatation using the Tryton side branch stent (Tryton-SBS). We hypothesized that FKBI improves anatomical reconstruction and functional results of bifurcation treated by Tryton-SBS. An unselected group of patients with complex bifurcation coronary lesions undergoing percutaneous coronary intervention (PCI) with Tryton-SBS underwent paired anatomical assessment with two- and three-dimensional quantitative coronary analysis (2D- and 3D-QCA), and optical coherence tomography (OCT), including 3D reconstruction before and after FKBI. Functional assessment by fractional flow reserve (FFR) was performed in the main branch (MB) and side branch (SB) before and after FKBI. Paired pre- and post-FKBI data were obtained in 10 patients. By OCT imaging, FKBI increased both the SB ostial area (4.93 ± 2.81 vs. 7.43 ± 2.87 mm 2 , P system, FKBI is associated with improved anatomical and functional results at the SB level, without compromising the result at the MB. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  3. Effect of Post-Dilatation Following Primary PCI With Everolimus-Eluting Bioresorbable Scaffold Versus Everolimus-Eluting Metallic Stent Implantation

    DEFF Research Database (Denmark)

    Yamaji, Kyohei; Brugaletta, Salvatore; Sabaté, Manel

    2017-01-01

    OBJECTIVES: This study sought to investigate the effect of post-dilatation on angiographic and intracoronary imaging parameters in the setting of primary percutaneous coronary intervention comparing the everolimus-eluting bioresorbable scaffold (BRS) with the everolimus-eluting metallic stent (EES......). BACKGROUND: Routine post-dilatation of BRS has been suggested to improve post-procedural angiographic and subsequent device-related clinical outcomes. METHODS: In the ABSORB STEMI TROFI II trial, 191 patients with ST-segment elevation myocardial infarction were randomly assigned to treatment with BRS (n = 95......) or EES (n = 96). Minimal lumen area and healing score as assessed by optical coherence tomography at 6 months were compared between BRS- and EES-treated patients stratified according to post-dilatation status. RESULTS: Primary percutaneous coronary intervention with post-dilatation was performed in 48...

  4. Short- versus long-term dual antiplatelet therapy after drug-eluting stent implantation: An individual patient data pairwise and network meta-analysis

    NARCIS (Netherlands)

    T. Palmerini (Tullio); D. Sangiorgi (Diego); M. Valgimigli (Marco); G.G. Biondi-Zoccai (Giuseppe); F. Feres (Fausto); A.C. Abizaid (Alexandre); R.A. Costa (Ricardo); M.K. Hong (Myeong); B.-K. Kim (Byeong-Keuk); Y. Jang (Yangsoo); H-S. Kim (Hyo-Soo); K.W. Park (Kyung Woo); A. Mariani (Andrea); D. Della Riva (Diego); P. Généreux (Philippe); M.B. Leon (Martin); D.L. Bhatt (Deepak); U. Bendetto (Umberto); C. Rapezzi (Claudio); G.W. Stone (Gregg)

    2015-01-01

    textabstractBackground Randomized controlled trials comparing short- (≤6 months) with long-term (≥1 year) dual antiplatelet therapy (DAPT) after drug-eluting stent(s) (DES) placement have been insufficiently powered to detect significant differences in the risk of major adverse cardiac events

  5. 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.

  6. Integrative measurements of calcifications in stented, antibiotic sterilized and cryopreserved sheep biological valves implanted for one year in tricuspid position.

    Science.gov (United States)

    Nozyński, Jerzy K; Zembala-Nozyńska, Ewa; Wilczek, Piotr; Wszołek, Jolanta

    2003-01-01

    The aim of the study was the characterization of calcification in the leaflets of a cryopreserved and alive heart valve depending on the diagnosed pathologic process. Sheep antibiotic sterilised and cryopreserved biological valves were implanted in tricuspid position in young sheeps for one year period. After this time the valves removed and studied morphologically. The control group consisted of 7 intact valves, the comparative group, so called group of valves after the processing antibiotic sterilization and cryopreservation consisted of 7 valves after mentioned procedures. Histological investigations were based on paraffin sections, calcium deposits were stained von Kossa technique. The measured values included integrative parameters as: 1. area fraction, 2. number of calcifications per area, 3. anisotropy. 1. A process of initial processing, sterilization and cryopreservation of biological valve increases a number of microcalcifications. 2. Cryopreserved biological valves explanted after one-year implantation into an animal in a tricuspid position possess fine calcifications and calcification foci. A number and size of fine calcifications decreases together with an intensification of degeneration and regressive processes of the connective tissue, especially in hyalinization. Hyalinization of the biological valve tissue seems to be favorable for a valve durability and as a pathological process decreasing calcification. 3. Mathematic analysis of morphometric features defining density and structure of calcifications indicate similarities among cryopreservation and initial processing groups, hyalinization, inflammation, whereas in a group of calcification foci, the similarity can be noticed between inflammation and hyalinization group.

  7. Experimental study on hemocompatibility of domestic silicone-covered stent

    International Nuclear Information System (INIS)

    Li Wentao; Wang Jianhua; Liu Qingxin; Qu Xudong

    2005-01-01

    Objective: To evaluate the hemocompatibility of domestic silicone-covered stent in the iliac arteries of canine model. Methods: Eighteen domestic stents were placed in iliac arteries of 9 adult dogs after larger balloon PTA, which included 10 silicone-covered stents and 8 bare stents for control. DSA was performed at 1, 4, 12 weeks after stent implantation in the iliac arteries of two groups to observe the outcomes of patency or restenosis. Animals were then euthanized isolating and staining the stented arteries with hematoxylin and eosin for histological examination. Finally, the acute thrombosis, reendothelialization and the neointimal proliferation of both covered and bare stents were quantified on histological cross-section. Results: All bare stents were patent in 12 weeks, but two silicone-covered stents were occluded at 4, 12 week respectively (patent rate was 80%). Stented vascular stenosis rate was averaging 72.3% at 12 week in covered stents and 36.7% in bare stents. Conclusions: The hemocompatibility of silicone-covered stents is not better than that of bare stents. Silicone appears to be inert in this experimental application. (authors)

  8. Short- and long-term outcomes of the titanium-NO stent registry.

    Science.gov (United States)

    Mosseri, Morris; Tamari, Israel; Plich, Michael; Hasin, Yonathan; Brizines, Mark; Frimerman, Aaron; Miller, Hilton; Jafari, Jamal; Guetta, Victor; Solomon, Mivi; Lotan, Chaim

    2005-01-01

    Five to 15% of the population have allergy to nickel, chromium, or molybdenum, which is a potential cause for in-stent restenosis. The Titan stent is made of stainless steel and is coated with titanium-nitride oxide (TiNOX), which completely prevents the discharge of metal elements. We performed a real-life multicenter registry to assess the short- and long-term characteristics of the Titan stent. A total of 103 Titan stents was implanted in 100 patients. Patients were 61.4+/-12.6 years old (81 men). Risk factors included hypercholesterolemia (63%), hypertension (53%), diabetes mellitus (DM; 35%), and current smoking (23%). Indications for PCI (percutaneous coronary intervention) were acute coronary syndromes (ACS) in 68% [acute ST elevation myocardial infarction (MI) in 8%], stable AP (angina pectoris) in 25%, and silent ischemia in 7% of the patients. Fifty-two percent of the treated lesions were of Type B2 or C. Lesion length was 14.3+/-2.9 mm and stent diameter was 3.06+/-0.36 mm. Indications for stenting were prevention of restenosis in 66%, residual stenosis in 33%, dissection in 13%, acute MI in 13%, and in-stent restenosis in 7% of the patients. Procedural success was 100%, with no complications. At 30 days, there were no major adverse cardiac events (MACE), including death, MI, and revascularization. At 180 days, only three patients had TVR (target vessel revascularization); two had TLR (target lesion revascularization) (one PCI and one CABG [coronary artery bypass grafting]), and one patient had a new narrowing proximal to the stent and underwent CABG due to multivessel disease. The Titan stent has a remarkable safety profile in high-risk patients and complex coronary lesions and excellent short- and long-term outcome with a very low clinical TLR rate.

  9. Biodegradable stents made of pure Mg and AZ91 alloy through SPS sintering

    OpenAIRE

    de Oliveira Botelho, Pedro Augusto

    2015-01-01

    The implantation of stents is an effective procedure to unblock the arteries of patients with serious heart problems. Traditionally, stents are made of inert materials such as stainless steel and titanium alloys. It has been shown that the traditional stents can cause restenosis or thrombosis. In recent years the proposal of biodegradable stents is attracting the interest of the industry and the research, since the stent is mechanically needed only in the first year, eliminating the problems ...

  10. Assessment of Atmospheric Pressure Plasma Treatment for Implant Osseointegration

    Directory of Open Access Journals (Sweden)

    Natalie R. Danna

    2015-01-01

    Full Text Available This study assessed the osseointegrative effects of atmospheric pressure plasma (APP surface treatment for implants in a canine model. Control surfaces were untreated textured titanium (Ti and calcium phosphate (CaP. Experimental surfaces were their 80-second air-based APP-treated counterparts. Physicochemical characterization was performed to assess topography, surface energy, and chemical composition. One implant from each control and experimental group (four in total was placed in one radius of each of the seven male beagles for three weeks, and one implant from each group was placed in the contralateral radius for six weeks. After sacrifice, bone-to-implant contact (BIC and bone area fraction occupancy (BAFO were assessed. X-ray photoelectron spectroscopy showed decreased surface levels of carbon and increased Ti and oxygen, and calcium and oxygen, posttreatment for Ti and CaP surfaces, respectively. There was a significant (P<0.001 increase in BIC for APP-treated textured Ti surfaces at six weeks but not at three weeks or for CaP surfaces. There were no significant (P=0.57 differences for BAFO between treated and untreated surfaces for either material at either time point. This suggests that air-based APP surface treatment may improve osseointegration of textured Ti surfaces but not CaP surfaces. Studies optimizing APP parameters and applications are warranted.

  11. Assessment of Atmospheric Pressure Plasma Treatment for Implant Osseointegration.

    Science.gov (United States)

    Danna, Natalie R; Beutel, Bryan G; Tovar, Nick; Witek, Lukasz; Marin, Charles; Bonfante, Estevam A; Granato, Rodrigo; Suzuki, Marcelo; Coelho, Paulo G

    2015-01-01

    This study assessed the osseointegrative effects of atmospheric pressure plasma (APP) surface treatment for implants in a canine model. Control surfaces were untreated textured titanium (Ti) and calcium phosphate (CaP). Experimental surfaces were their 80-second air-based APP-treated counterparts. Physicochemical characterization was performed to assess topography, surface energy, and chemical composition. One implant from each control and experimental group (four in total) was placed in one radius of each of the seven male beagles for three weeks, and one implant from each group was placed in the contralateral radius for six weeks. After sacrifice, bone-to-implant contact (BIC) and bone area fraction occupancy (BAFO) were assessed. X-ray photoelectron spectroscopy showed decreased surface levels of carbon and increased Ti and oxygen, and calcium and oxygen, posttreatment for Ti and CaP surfaces, respectively. There was a significant (P < 0.001) increase in BIC for APP-treated textured Ti surfaces at six weeks but not at three weeks or for CaP surfaces. There were no significant (P = 0.57) differences for BAFO between treated and untreated surfaces for either material at either time point. This suggests that air-based APP surface treatment may improve osseointegration of textured Ti surfaces but not CaP surfaces. Studies optimizing APP parameters and applications are warranted.

  12. Real-world antithrombotic therapies and clinical outcomes after second-generation drug-eluting stent implantation in patients with atrial fibrillation: a multi-center cohort study.

    Science.gov (United States)

    Otsuki, Hisao; Yamaguchi, Junichi; Kamishima, Kazuho; Arashi, Hiroyuki; Hagiwara, Nobuhisa

    2018-03-16

    Previous reports have focused on cardiovascular and bleeding events in patients with atrial fibrillation (AF) undergoing percutaneous coronary intervention (PCI). However, antithrombotic treatment strategies and clinical outcomes after second-generation drug-eluting stents (DES) implantation in AF patients remain to be determined. We enrolled 244 consecutive AF patients treated with second-generation DES. The study population was derived from multi-center AF registry (including 8 centers in Japan) from 2010 to 2012. Prescription of antithrombotic agents and clinical outcomes were retrospectively examined. Ninety-two patients (37.7%) were prescribed dual antiplatelet therapy (DAPT) at discharge and 152 patients (62.3%) were given DAPT plus oral anticoagulation (OAC) with warfarin. The median follow-up period was 730 days. Kaplan-Meier analysis showed that major adverse cardiac and cerebrovascular events (MACCE) were not significantly different (2-year event rate, 17.6 vs. 13.5%, p = 0.37), but bleeding events were significantly higher in the DAPT plus OAC group than in the DAPT group (2-year event rate, 6.1 vs. 17.9%, p = 0.033). In a sub-analysis of DAPT plus OAC patients, adequate time in the therapeutic range (TTR) group (TTR ≥ 65%) was not significantly different from the suboptimal OAC group (TTR < 65%) for bleeding events, but it had a lower incidence of MACCE, resulting in better net clinical outcomes (composite of MACCE and major bleeding, 2-year event rate, 9.2 vs. 27.8%, p = 0.008). DAPT plus OAC remains more common in AF patients undergoing PCI with second-generation DES. Under adequate TTR, DAPT plus OAC showed better net clinical outcomes by reducing MACCE without increasing bleeding.

  13. Five-year outcome after implantation of zotarolimus- and everolimus-eluting stents in randomized trial participants and nonenrolled eligible patients : A secondary analysis of a randomized clinical trial

    NARCIS (Netherlands)

    Von Birgelen, Clemens; Van Der Heijden, Liefke C.; Basalus, Mounir Welson Zakhary; Kok, Marlies M.; Sen, Hanim; Louwerenburg, Hans W.; van Houwelingen, Gert K.; Stoel, Martin G.; de Man, Frits H.A.F.; Linssen, Gerard C.M.; Tandjung, Kenneth; Doggen, Carine J.M.; Van Der Palen, Job; Löwik, Marije M.

    2017-01-01

    IMPORTANCE: Long-term follow-up after a clinical trial of 2 often-used, newer-generation drug-eluting stents (DESs) in a broad patient population is of interest. Comprehensive long-term outcome of eligible nonenrolled patients has never been reported. OBJECTIVE: To assess 5-year safety and efficacy

  14. Real-World Bioresorbable Vascular Scaffold Experience Compared With Second-Generation Metallic Drug-Eluting Stents in Complex Coronary Lesions.

    Science.gov (United States)

    Okamoto, Naotaka; Ueda, Hiroshi; Yoshimura, Takahiro; Chamaria, Surbhi; Bhatheja, Samit; Vengrenyuk, Yuliya; Rabiei, Samaneh; Barrientos, Yonandy; Kapur, Vishal; Barman, Nitin; Sweeny, Joseph; Baber, Usman; Mehran, Roxana; Sharma, Samin K; Kini, Annapoorna S

    2018-04-15

    The aim of the study was to compare the acute outcomes of Absorb bioresorbable vascular scaffolds (BVS) and second-generation drug-eluting stent (DES) implantation in routine clinical practice. There is a paucity of data regarding BVS use in a real-world patient population. The study population comprised 40 consecutive patients who underwent percutaneous coronary intervention (PCI) with BVS implantation at a tertiary-care center in New York, New York between July and December of 2016. An optimal implantation technique including adequate lesion preparation, mandatory postdilation, and optical coherence tomography (OCT) imaging was used in all cases. De novo lesions treated with BVS were compared to lesions treated with DES matched by OCT calcium arc, scaffold/stent size, use of atherectomy device, and lesion postdilation. Acute lumen gain, minimal device area, malapposition, eccentricity, and symmetry index were assessed using OCT. We analyzed OCT images of 40 BVS cases and 40 matching DES cases from 35 and 40 patients, respectively. Compared to the DES group, the BVS group demonstrated similar acute lumen gain, minimal scaffold/stent area, eccentricity index, and symmetry index after PCI. There were fewer malapposed struts detected after BVS implantation; however, malapposition distance and length were not different between the groups. BVS implantation in a real-world patient population with optimal implantation technique resulted in similar stent expansion and better strut apposition compared to DES implantation.

  15. Effects of Intravascular Ultrasound-Guided Versus Angiography-Guided New-Generation Drug-Eluting Stent Implantation: Meta-Analysis With Individual Patient-Level Data From 2,345 Randomized Patients.

    Science.gov (United States)

    Shin, Dong-Ho; Hong, Sung-Jin; Mintz, Gary S; Kim, Jung-Sun; Kim, Byeong-Keuk; Ko, Young-Guk; Choi, Donghoon; Jang, Yangsoo; Hong, Myeong-Ki

    2016-11-14

    The aim of this study was to evaluate the clinical usefulness of intravascular ultrasound (IVUS)-guided new-generation drug-eluting stent (DES) implantation using a meta-analysis of individual patient-level data from randomized trials. Published randomized trials that compare IVUS-guided versus angiography-guided new-generation DES implantation are scarce. Searches of the MEDLINE, Embase, and Cochrane databases were performed to find randomized trials that compared IVUS-guided versus angiography-guided new-generation DES implantation. A total of 2,345 patients from 3 randomized trials were identified, and all patients were treated for long lesions or chronic total occlusions. Individual patient-level data were obtained. The primary endpoint was a major adverse cardiac event, a composite of cardiac death, myocardial infarction, or stent thrombosis. An intention-to-treat analysis and per protocol analysis were performed. By 1 year post-procedure, major adverse cardiac events had occurred in 0.4% of the patients who underwent IVUS-guided DES implantation versus 1.2% of those who underwent angiography-guided DES implantation (hazard ratio [HR]: 0.36; 95% confidence interval [CI]: 0.13 to 0.99; p = 0.040). For the IVUS-guided group, favorable clinical outcomes were observed for myocardial infarction (0% vs. 0.4%; HR: 0.09; p = 0.026). In addition, the clinical benefit of IVUS guidance was stronger in the per protocol analysis (HR: 0.32; 95% CI: 0.12 to 0.89; p = 0.021). Compared with angiographic guidance, IVUS-guided new-generation DES implantation was associated with favorable outcomes in terms of major adverse cardiac events, the composite of cardiac death, myocardial infarction, or stent thrombosis. These findings must be interpreted only for complex lesions, because all identified patients had long lesions or chronic total occlusions. Copyright © 2016 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  16. 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

  17. 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.

  18. Investigating the flow dynamics in the obstructed and stented ureter by means of a biomimetic artificial model.

    Directory of Open Access Journals (Sweden)

    Francesco Clavica

    Full Text Available Double-J stenting is the most common clinical method employed to restore the upper urinary tract drainage, in the presence of a ureteric obstruction. After implant, stents provide an immediate pain relief by decreasing the pressure in the renal pelvis (P. However, their long-term usage can cause infections and encrustations, due to bacterial colonization and crystal deposition on the stent surface, respectively. The performance of double-J stents - and in general of all ureteric stents - is thought to depend significantly on urine flow field within the stented ureter. However very little fundamental research about the role played by fluid dynamic parameters on stent functionality has been conducted so far. These parameters are often difficult to assess in-vivo, requiring the implementation of laborious and expensive experimental protocols. The aim of the present work was therefore to develop an artificial model of the ureter (i.e. ureter model, UM to mimic the fluid dynamic environment in a stented ureter. The UM was designed to reflect the geometry of pig ureters, and to investigate the values of fluid dynamic viscosity (μ, volumetric flow rate (Q and severity of ureteric obstruction (OB% which may cause critical pressures in the renal pelvis. The distributed obstruction derived by the sole stent insertion was also quantified. In addition, flow visualisation experiments and computational simulations were performed in order to further characterise the flow field in the UM. Unique characteristics of the flow dynamics in the obstructed and stented ureter have been revealed with using the developed UM.

  19. Estudo da resposta tissular à endoprótese recoberta de jugular bovina em veia cava inferior de suínos Bovine jugular covered stent-graft implanted in swine inferior vena cava - a study of tissue response

    Directory of Open Access Journals (Sweden)

    Cristina Ribeiro Riguetti Pinto

    2006-06-01

    Full Text Available OBJETIVO: Avaliar a resposta tissular a uma endoprótese, com cobertura biológica heteróloga, implantada em veia cava inferior de suínos. MÉTODO: Desenvolvemos uma endoprótese auto-expansível, revestida com um segmento de jugular bovina, conservada por processo L-hydro e suturada em um stent de aço inoxidável 316L. O dispositivo introdutor utilizado foi a bainha de liberação da endoprótese aórtica Taheri-Leonhardt (Flórida, EUA. Foram implantadas endopróteses em 10 suínos, todas na veia cava infra-renal. Os animais foram submetidos à flebografia peroperatória. À necropsia, após 2 meses, cada endoprótese foi retirada em bloco e analisada macroscopicamente, visando a avaliação da perviedade, aderência aos tecidos vizinhos e incorporação à parede venosa; e, histopatologicamente, visando a resposta histológica ao enxerto. RESULTADOS: Na análise macroscópica, todas as endopróteses encontravam-se pérvias e totalmente incorporadas à parede venosa, porém seis apresentavam trabeculações grosseiras no seu interior e quatro algum grau de fibrose perivascular. Três animais desenvolveram linfocele, uma retroperitoneal e as outras na parede abdominal. No estudo histopatológico, observamos reação inflamatória granulomatosa tipo corpo estranho em todos os casos, sendo predominante na camada média (80%. CONCLUSÃO: O modelo estudado apresentou baixa trombogenicidade, corroborando com a eficácia do meio de conservação e material escolhidos; porém, baixa biocompatibilidade, provavelmente pelo obstáculo imunológico dos xenoenxertos e resposta tissular exagerada do território venoso.OBJECTIVE: To evaluate tissue response to a bovine jugular vein covered stent when implanted in the swine inferior vena cava. METHOD: We developed a self-expanding stent, using a segment of L-hydro conserved bovine jugular vein, which was trimmed and sutured to a 316L stainless steel stent. We used the Taheri-Leonhardt delivery system for

  20. Safety and efficacy assessment of carotid artery stenting in a high-risk population in a single-centre registry.

    Science.gov (United States)

    Kosowski, Michał; Zimoch, Wojciech; Gwizdek, Tomasz; Konieczny, Radosław; Kübler, Piotr; Telichowski, Artur; Jankowska, Ewa A; Reczuch, Krzysztof

    2014-01-01

    Ischaemic stroke is the primary cause of long-term disability and the third most common cause of death. Internal carotid artery stenosis is an important risk factor for stroke and transient ischaemic attack (TIA). European Society of Cardiology (ESC) and American Heart Association (AHA) guidelines allow carotid artery stenting (CAS) as an alternative to endarterectomy in centres with low rates of death or stroke. To assess the safety and efficacy of CAS in a single-centre observation. We performed a retrospective analysis of all patients treated with CAS between March 2008 and July 2012. Clinical data and outcomes in both asymptomatic and symptomatic patients were analysed. A total of 214 consecutive patients were included in the registry. Symptomatic patients accounted for 57% of the study group and were more likely to have a history of stroke and/or TIA that occurred more than 6 months before the procedure (50% vs. 8%, p likely to have a history of coronary artery disease (88% vs. 61%, p < 0.001), and the rates of previous acute coronary syndrome and revascularisation were also higher in this group (58% vs. 41% and 71% vs. 52%, respectively, both p < 0.05). The symptomatic group had higher incidence of stroke in periprocedural and 30-day observation (4% vs. 0%, p < 0.05). There was no difference in incidence of adverse events in long-term observation. Carotid artery stenting is a safe and efficacious procedure. Every centre performing CAS should monitor the rate of periprocedural complications.

  1. Late clinical outcomes after implantation of drug-eluting stents coated with biodegradable polymers: 3-year follow-up of the PAINT randomised trial.

    Science.gov (United States)

    Lemos, Pedro A; Moulin, Bruno; Perin, Marco A; Oliveira, Ludmilla A R R; Arruda, J Airton; Lima, Valter C; Lima, Antonio A G; Caramori, Paulo R A; Medeiros, Cesar R; Barbosa, Mauricio R; Brito, Fabio S; Ribeiro, Expedito E

    2012-05-15

    The long-term clinical performance of drug-eluting stents (DES) coated with biodegradable polymers is poorly known. A total of 274 coronary patients were randomly allocated to paclitaxel-eluting stents, sirolimus-eluting stents, or bare metal stents (2:2:1 ratio). The two DES used the same biodegradable polymers and were identical except for the drug. At three years, the pooled DES population had similar rates of cardiac death or myocardial infarction (9.0% vs. 7.1; p=0.6), but lower risk of repeat interventions (10.0% vs. 29.9%; pbiodegradable-polymer coated DES releasing either paclitaxel or sirolimus were effective in reducing the 3-year rate of re-interventions.

  2. Treatment of Benign Tracheal Stenosis Utilizing Self-Expanding Nitinol Stents

    International Nuclear Information System (INIS)

    Sesterhenn, Andreas M.; Wagner, Hans-Joachim; Alfke, Heiko; Werner, Jochen A.; Lippert, Burkard M.

    2004-01-01

    We assessed the results of self-expanding metallic stent insertion into benign proximal tracheal stenosis in patients not appropriate or unfit for surgical repair. Proximal benign tracheal stenoses had occurred in 11 patients (7 men, 4 women, mean age 68.8 years) after long-time intubation (n = 6), tracheostomy (n = 4), or chondropathia (n = 1). Fourteen self-expanding nitinol stents were placed in the patients under general anesthesia with endoscopical and fluoroscopical guidance. Stent insertion was successful in all cases and led to immediate relief of the morphological and functional airway obstruction. No immediate complications were noted. During the mean follow-up period of 67.5 weeks we observed one recurrent dyspnea 3 months after implantation and granuloma formation at the stent insertion site in another patient. Both complications were successfully treated with additional stent insertion in one case and laser resection of granulomas in the other. Self-expanding nitinol stents should be considered for the treatment of benign proximal tracheal obstruction in selected patients for whom surgical repair is contraindicated

  3. Stent longitudinal strength assessed using point compression: insights from a second-generation, clinically related bench test.

    Science.gov (United States)

    Ormiston, John A; Webber, Bruce; Ubod, Ben; White, Jonathon; Webster, Mark W I

    2014-02-01

    Stent longitudinal distortion, while infrequent, can lead to adverse clinical events. Our first bench comparison of susceptibility of different stent designs to distortion applied force to the entire circumference of the proximal stent hoop. The test increased understanding of stent design and led to recommendations for design change in some. Our second-generation test more closely mimics clinical scenarios by applying force to a point on the proximal hoop of a malapposed stent. Each 3-mm-diameter stent was secured in a test apparatus so that its proximal 5 mm was malapposed in a 3.5-mm tube. An instron applied force to the proximal hoop of each of 5 examples of each of 6 stent designs using a narrow rod so that force applied and distance compressed could be measured. Hoops on the side of the force were pushed together, became malapposed, and obstructed the lumen. In addition, the proximal stent hoop tilted causing malapposition, the contralateral side of the stent from the applied force causing lumen obstruction. This second-generation, more clinically relevant test showed the Biomatrix Flex was the most resistant to deformation and the Element the most easily deformed. The addition of more connectors between the proximal hoops in the Promus Premier design has reduced the potential for distortion when compared with the Element, so that distortion was similar to the Vision, Multi-Link 8, and Integrity designs. The test also provided insight into the way in which stents are likely to distort in clinical practice.

  4. IVUS Findings in Late and Very Late Stent Thrombosis. A Comparison Between Bare-metal and Drug-eluting Stents.

    Science.gov (United States)

    Fuentes, Lara; Gómez-Lara, Josep; Salvatella, Neus; Gonzalo, Nieves; Hernández-Hernández, Felipe; Fernández-Nofrerias, Eduard; Sánchez-Recalde, Ángel; Alfonso, Fernando; Romaguera, Rafael; Ferreiro, José Luis; Roura, Gerard; Teruel, Luis; Gracida, Montserrat; Marcano, Ana Lucrecia; Gómez-Hospital, Joan-Antoni; Cequier, Ángel

    2017-09-01

    Stent thrombosis (ST) is a life-threatening complication after stent implantation. Intravascular ultrasound is able to discern most causes of ST. The aim of this study was to compare intravascular ultrasound findings between bare-metal stents (BMS) and drug-eluting stents (DES) in patients with late (31 days to 1 year) or very late ST (> 1 year). Of 250 consecutive patients with late or very late ST in 7 Spanish institutions, 114 patients (45.5% BMS and 54.5% DES) were imaged with intravascular ultrasound. Off-line intravascular ultrasound analysis was performed to assess malapposition, underexpansion, and neoatherosclerosis. The median time from stent implantation to ST was 4.0 years with BMS and 3.4 years with DES (P = .04). Isolated malapposition was similarly observed in both groups (36.5% vs 46.8%; P = .18) but was numerically lower with BMS (26.6% vs 48.0%; P = .07) in patients with very late ST. Isolated underexpansion was similarly observed in both groups (13.5% vs 11.3%; P = .47). Isolated neoatherosclerosis occurred only in patients with very late ST and was more prevalent with BMS (22.9%) than with DES (6.0%); P = .02. At 2.9 years' follow-up, there were 0% and 6.9% cardiac deaths, respectively (P = .06) and recurrent ST occurred in 4.0% and 5.2% of patients, respectively (P = .60). Malapposition was the most common finding in patients with late and very late ST and is more prevalent with DES in very late ST. In contrast, neoatherosclerosis was exclusively observed in patients with very late ST and mainly with BMS. Copyright © 2017 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.

  5. Critical Assessment of Implantable Drug Delivery Devices in Glaucoma Management

    Directory of Open Access Journals (Sweden)

    Dharani Manickavasagam

    2013-01-01

    Full Text Available Glaucoma is a group of heterogeneous disorders involving progressive optic neuropathy that can culminate into visual impairment and irreversible blindness. Effective therapeutic interventions must address underlying vulnerability of retinal ganglion cells (RGCs to degeneration in conjunction with correcting other associated risk factors (such as elevated intraocular pressure. However, realization of therapeutic outcomes is heavily dependent on suitable delivery system that can overcome myriads of anatomical and physiological barriers to intraocular drug delivery. Development of clinically viable sustained release systems in glaucoma is a widely recognized unmet need. In this regard, implantable delivery systems may relieve the burden of chronic drug administration while potentially ensuring high intraocular drug bioavailability. Presently there are no FDA-approved implantable drug delivery devices for glaucoma even though there are several ongoing clinical studies. The paper critically assessed the prospects of polymeric implantable delivery systems in glaucoma while identifying factors that can dictate (a patient tolerability and acceptance, (b drug stability and drug release profiles, (c therapeutic efficacy, and (d toxicity and biocompatibility. The information gathered could be useful in future research and development efforts on implantable delivery systems in glaucoma.

  6. An in vivo assessment of the effects of using different implant abutment occluding materials on implant microleakage and the peri-implant microbiome

    Science.gov (United States)

    Rubino, Caroline

    Microleakage may be a factor in the progression of peri-implant pathology. Microleakage in implant dentistry refers to the passage of bacteria, fluids, molecules or ions between the abutment-implant interface to and from the surrounding periodontal tissues. This creates a zone of inflammation and reservoir of bacteria at the implant-abutment interface. Bone loss typically occurs within the first year of abutment connection and then stabilizes. It has not yet been definitively proven that the occurrence of microleakage cannot contribute to future bone loss or impede the treatment of peri-implant disease. Therefore, strategies to reduce or eliminate microleakage are sought out. Recent evidence demonstrates that the type of implant abutment channel occluding material can affect the amount of microleakage in an in vitro study environment. Thus, we hypothesize that different abutment screw channel occluding materials will affect the amount of observed microleakage, vis-a-vis the correlation between the microflora found on the abutment screw channel occluding material those found in the peri-implant sulcus. Additional objectives include confirming the presence of microleakage in vivo and assessing any impact that different abutment screw channel occluding materials may have on the peri-implant microbiome. Finally, the present study provides an opportunity to further characterize the peri-implant microbiome. Eight fully edentulous patients restored with at dental implants supporting screw-retained fixed hybrid prostheses were included in the study. At the initial appointment (T1), the prostheses were removed and the implants and prostheses were cleaned. The prostheses were then inserted with polytetrafluoroethylene tape (PTFE, TeflonRTM), cotton, polyvinyl siloxane (PVS), or synthetic foam as the implant abutment channel occluding material and sealed over with composite resin. About six months later (T2), the prostheses were removed and the materials collected. Paper

  7. Evaluation of in-stent restenosis in the APPROACH trial (assessment on the prevention of progression by Rosiglitazone on atherosclerosis in diabetes patients with cardiovascular history)

    NARCIS (Netherlands)

    H.M. Garcia-Garcia (Hector); S.A. Garg (Scot); S. Brugaletta (Salvatore); G. Morocutti (Giorgio); R.E. Ratner (Robert); N.S. Kolatkar (Nikheel); B.G. Kravitz (Barbara); D.M. Miller (Diane); C. Huang (Chunmei); R.W. Nesto (Richard); P.W.J.C. Serruys (Patrick); R.P. Aftring (R.); N.S. Kolatkar (Nikheel); B.G. Kravitz (Barbara); J. Wolstenholme (Jane); J. Saarinen (Jari); R. Fowler (R.); J. Hoffman (Jonathan); D. Steele-Norwood (D.); R. Russell (Robert); S. Young (S.); Y.F. Chou; S. McMorn (Steve); C. Kirsch (Courtney); B. Louridas (Bonnie); T. Olivieria (Teresa); D. Mattioli (Debra); D. Miller (D.); C. Huang (Chunmei); C. Nguyen (C.); K. Jahnke (Kristoph); G.S. Mintz (Gary); J. Lachin (J.); M. Abrahamson (M.); P. Carson (P.); P. Jones

    2012-01-01

    textabstractTo determine (1) the medium-term effect of rosiglitazone and glipizide on intra-stent neointima hyperplasia, (2) restenosis pattern as assessed by intravascular ultrasound (IVUS) and quantitative coronary angiography (QCA) in patients with T2DM and coronary artery disease. A total of 462

  8. Percutaneous therapy of inoperable biliary stenoses and occlusions with a new self-expanding nitinol stent (SMART); Perkutane Therapie inoperabler maligner Stenosen und Verschluesse der Gallenwege mit einem neu entwickelten selbstexpandierbaren Nitinolstent (SMART)

    Energy Technology Data Exchange (ETDEWEB)

    Zorger, N.; Lenhart, M.; Strotzer, M.; Paetzel, C.; Hamer, O.; Feuerbach, S.; Link, J. [Regensburg Univ. (Germany). Inst. fuer Roentgendiagnostik

    2002-10-01

    Objective: To evaluate the treatment of malignant biliary stenoses and occlusions using a new stent. Methods: In a prospective study, 25 patients with malignant obstructive jaundice were treated with SMART stents. The handling and the quality of stent expansion were documented. Stent function was assessed 2-4 days after intervention by cholangiography and laboratory tests. A follow-up was performed three months, after stent placement. Results: All lesions were treated successfully, with a total of 35 stents implanted. In 14 patients a further balloon dilatation was performed after stent placement (8-10 mm diameter/40-80 mm length). The mean serum bilirubin level decreased significantly from 11.6 mg/dl to 4.6 mg/dl after intervention (p<0.05). The follow-up showed a mean serum bilirubin level at 4.0 mg/dl. In 4 cases (16%) a further intervention (PTCD or stent) was performed. Six patients died due to tumor progression. The stents proved to be patent in 79% (n=15) of patients alive at the time of follow-up. Conclusions: Placement of the SMART stent for the therapy of malignant biliary lesions yields good technical and clinical results. (orig.) [German] Zielsetzung: Evaluation der technischen Handhabung und Effizienz eines neu entwickelten Stents zur Therapie maligner Gallenwegsstenosen und Verschluesse. Material und Methodik: In einer prospektiven Studie wurden 25 Patienten mit Verschlussikterus bei maligner Gallengangsstenose palliativ mit dem SMART {sup trademark} -Stent behandelt. Evaluiert wurden die Handhabung des Stents und die Qualitaet der Stententfaltung. Die Stentfunktion wurde nach 2-4 Tagen ueber eine liegende interne/externe Drainage cholangiographisch sowie anhand des Verlaufs der Laborparameter kontrolliert. Eine zusaetzliche Kontrolle der Stentfunktion erfolgte nach drei Monaten. Dabei wurden das subjektive Wohlbefinden des Patienten, der aktuelle Gesamtbilirubinspiegel im Serum und die Anzahl weiterer, im Nachsorgezeitraum durchgefuehrter

  9. Comparison of Acute Recoil between Bioabsorbable Poly-L-lactic Acid XINSORB Stent and Metallic Stent in Porcine Model

    Directory of Open Access Journals (Sweden)

    Yizhe Wu

    2012-01-01

    Full Text Available Objective. To investigate acute recoil of bioabsorbable poly-L-lactic acid (PLLA stent. Background. As newly developed coronary stent, bioabsorbable PLLA stent still encountered concern of acute stent recoil. Methods. Sixteen minipigs were enrolled in our study. Eight PLLA XINSORB stents (Weite Biotechnology Co., Ltd., China and eight metallic stents (EXCEL, Jiwei Co., Ltd. China were implanted into coronary arteries. Upon quantitative coronary angiography analysis, acute absolute recoil was defined as the difference between mean diameter of inflated balloon (X and mean lumen diameter of stent immediately after deployment (Y, while acute percent recoil was defined as (X−Y/X and expressed as a percentage. Intravascular ultrasound (IVUS was performed immediately after implantation and 24 hours later to compare cross-sectional area (CSA between two groups and detect stent malapposition or collapse. Results. Acute absolute recoil in XINSORB and EXCEL was 0.02±0.13 mm and −0.08±0.08 mm respectively (P=0.19. Acute percent recoil in XINSORB and EXCEL was 0.66±4.32% and −1.40±3.83%, respectively (P=0.45. CSA of XINSORB was similar to that of EXCEL immediately after implantation, so was CSA of XINSORB at 24-hours followup. Within XINSORB group, no difference existed between CSA after implantation and CSA at 24-hours followup. No sign of acute stent malapposition was detected by IVUS. Conclusions. The acute stent recoil of XINSORB is similar to that of EXCEL. No acute stent malapposition or collapse appeared in both kinds of stent. This preclinical study was designed to provide preliminary data for future studies of long-term efficacy and safety of XINSORB stent.

  10. Angiographic patterns of in-stent restenosis classified by computed tomography in patients with drug-eluting stents: correlation with invasive coronary angiography

    International Nuclear Information System (INIS)

    Pan, Jingwei; Lu, Zhigang; Wei, Meng; Zhang, Jiayin; Li, Minghua

    2013-01-01

    To evaluate the diagnostic accuracy of Mehran's in-stent restenosis (ISR) classification by coronary computed angiography (CCTA), with reference to invasive coronary angiography (ICA). Consecutive symptomatic patients, who had clinically suspected ISR and implanted stent diameter ≥ 3 mm, were prospectively enrolled in our study. Mehran's classification was employed by CCTA and ICA to classify ISR lesions into four subtypes: focal, diffuse intrastent, diffuse proliferative and total occlusion. CCTA and ICA measurement of lesion length was further compared. Sixty-one patients with 101 implanted stents were included in our study. The overall sensitivity, specificity, PPV and NPV of CCTA diagnosis of binary ISR, as shown by patient-based analysis (n = 61), were 100 % (49/49), 75 % (8/12), 92.45 % (49/53) and 100 % (8/8) respectively. Mehran's classification of CCTA correlated well with ICA findings. The diagnostic accuracy of CCTA for class I, class II, class III and class IV lesions was 92.5 %, 91.67 %, 100 % and 100 % respectively. Lesion length was assessed to be significantly longer with CCTA than with ICA (11.03 ± 5.89 mm versus 8.56 ± 4.99 mm, P < 0.001). Angiographic patterns of in-stent restenosis can be accurately classified by coronary computed angiography. The lesion length measured by CCTA is longer than that assessed by invasive coronary angiography. (orig.)

  11. Optimal scanning protocols of 64-slice CT angiography in coronary artery stents: An in vitro phantom study

    Energy Technology Data Exchange (ETDEWEB)

    Almutairi, Abdulrahman Marzouq [Discipline of Medical Imaging, Department of Imaging and Applied Physics, Curtin University of Technology, Perth, Western Australia (Australia); Sun Zhonghua [Discipline of Medical Imaging, Department of Imaging and Applied Physics, Curtin University of Technology, Perth, Western Australia (Australia)], E-mail: z.sun@curtin.edu.au; Ng, Curtise [Discipline of Medical Imaging, Department of Imaging and Applied Physics, Curtin University of Technology, Perth, Western Australia (Australia); Al-Safran, Zakariya A.; Al-Mulla, Abeer A.; Al-Jamaan, Abdulaziz I. [Department of Medical Imaging, King Fahad Specialist Hospital, Dammam (Saudi Arabia)

    2010-04-15

    Purpose: The purpose of the study was to investigate the optimal scanning protocol of 64-slice CT angiography for assessment of coronary artery stents based on a phantom study. Materials and methods: Coronary stents with a diameter of 2.5 mm was implanted in thin plastic tubes with an inner diameter of 3.0 mm to simulate a coronary artery. The tubes were filled with iodinated contrast medium diluted to 178 HU, closed at both ends and positioned in a plastic container filled with vegetable oil (-70 to -100 HU). A series of scans were performed with a 64-slice CT scanner with the following protocols: section thickness: 0.67 mm, 1.0 mm, 1.5 mm, 2.0 mm, pitch value: 0.2, 0.3, 0.5 and reconstruction interval of 50% overlap of the section thickness. 2D axial and multiplanar reformatted images were generated to assess the visibility of stent lumen, while virtual intravascular endoscopy (VIE) was reconstructed to evaluate the artery wall and stent surface. Results: Our results showed that a scanning protocol of 1.0 mm slice thickness with a pitch of 0.3 produced acceptable images with best demonstration of the intrastent lumen and stent surface with minimal image noise or artifacts. In contrast, submillimeter scans with 0.67 mm resulted in moderate artifacts which affected visualization of the coronary lumen, in addition to the increased noise. When the section thickness increased to 1.5 mm and 2.0 mm, visualization of the artery wall and stent surface was compromised, although the intrastent lumen was still visible. Conclusion: Our in vitro study suggested that a scanning protocol of 1.0 mm section thickness with pitch of 0.3 is the optimal protocol for evaluation of coronary artery stents as it allows generation of acceptable images with better visualization of stent lumen, stent surface and coronary artery wall.

  12. In Vitro and In Vivo Assessment of Docetaxel Formulation Developed for Esophageal Stents.

    Science.gov (United States)

    Shaikh, Mohsin; Zhang, Huihui; Wang, Hongyuan; Guo, Xiuli; Song, Yunmei; Kanwar, Jagat Rakesh; Garg, Sanjay

    2017-01-01

    Esophageal cancer (EC) mostly affects the elderly population and is frequently diagnosed at an advanced stage. Self-expanding metal stents (SEMS) are the most popular mode of palliation, but they are associated with reocclusion caused by tumor growth. To overcome this problem, docetaxel (DTX)-loaded polyurethane formulations were prepared for stent application. The films were evaluated against the cancer cell lines, OE-19 and OE-21, and normal esophageal cell line Het-1A. The DTX and the formulations were evaluated in vitro for the cytotoxicity and in vivo in nude mice. It was found that DTX and the formulations have a weak activity against the EC cell lines and an even weaker activity against Het-1A cell line. Preliminary in vivo studies showed skin toxicity in nude mice necessitating modification of the formulation. Reevaluation in a mouse xenograft model resulted in toxicity at high dose formulations while the low dose formulation exhibited modest advantage over commercial IV formulation; however, there was no significant difference between the commercial IV and blank formulation. DTX combination with an anti-cancer agent having complementary mode of action and non-overlapping toxicity could yield better outcome in future.

  13. 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.

  14. 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)

  15. Antirestenotic Effects of a Novel Polymer-Coated D-24851 Eluting Stent. Experimental Data in a Rabbit Iliac Artery Model

    International Nuclear Information System (INIS)

    Lysitsas, Dimitrios N.; Katsouras, Christos S.; Papakostas, John C.; Toumpoulis, Ioannis K.; Angelidis, Charalampos; Bozidis, Petros; Thomas, Christopher G.; Seferiadis, Konstantin; Psychoyios, Nikolaos; Frillingos, Stathis; Pavlidis, Nikolaos; Marinos, Euaggelos; Khaldi, Lubna; Sideris, Dimitris A.; Michalis, Lampros K.

    2007-01-01

    Experimental and clinical data suggest that stents eluting antiproliferative agents can be used for the prevention of in-stent restenosis. Here we investigate in vitro the antiproliferative and apoptotic effect of D-24851 and evaluate the safety and efficacy of D-24851-eluting polymer-coated stents in a rabbit restenosis model (n = 53). Uncoated stents (n = 6), poly (dl-lactide-co-glycolide) (PLGA)-coated stents (n = 7), and PLGA-coated stents loaded with 0.08 ± 0.0025 μM (31 ± 1 μg; low dose; n = 7), 0.55 ± 0.02 μM (216 ± 8 μg; high dose; n = 6), and 4.55 ± 0.1 μM (1774 ± 39 μg; extreme dose; n = 5) of D-24851 were randomly implanted in New Zealand rabbit right iliac arteries and the animals were sacrificed after 28 days for histomorphometric analysis. For the assessment of endothelial regrowth in 90 days, 12 rabbits were subjected to PLGA-coated (n = 3), low-dose (n = 3), high-dose (n = 3), and extreme-dose (n = 3) stent implantation. In vitro studies revealed that D-24851 exerts its growth inhibitory effects via inhibition of proliferation and induction of apoptosis without increasing the expression of heat shock protein-70, a cytoprotective and antiapoptotic protein. Treatment with low-dose D-24851 stents was associated with a significant reduction in neointimal area and percentage stenosis only compared with bare metal stents (38% [P = 0.029] and 35% [P = 0.003] reduction, respectively). Suboptimal healing, however, was observed in all groups of D-24851-loaded stents in 90 days in comparison with PLGA-coated stents. We conclude that low-dose D-24851-eluting polymer-coated stents significantly inhibit neointimal hyperplasia at 28 days through inhibition of proliferation and enhancement of apoptosis. In view of the suboptimal re-endothelialization, longer-term studies are needed in order to establish whether the inhibition of intimal growth is maintained

  16. Early and Long-Term Results of Stent Implantation for Aortic Coarctation in Pediatric Patients Compared to Adolescents: A Single Center Experience

    Directory of Open Access Journals (Sweden)

    Sara Bondanza

    2016-01-01

    Full Text Available Background. Stents have become the treatment of choice for native aortic coarctation in adults and adolescents, but in pediatric patients insufficient data are currently available to identify the best therapeutic option. Methods. To compare the outcomes of pediatric and adolescent patients, we retrospectively evaluated early and long-term results of stenting for aortic coarctation in 34 patients divided into 2 groups (A and B composed, respectively, of 17 children (mean age 8.2±2.3, weight ≤30 kg and 17 adolescents (mean age 14.3±1.7, weight >30 kg. Results. No significant differences in outcome were found between groups immediately after the procedure. In all of our patients, peak systolic gradient pressure significantly decreased after stenting from 43.7±12 to 1.7±3.1 mmHg in group A and from 39.4±16.8 to 1.6±3 in group B (p<0.0001. We observed early and late adverse events in both groups: early femoral vessel injury or thrombosis was more frequent in younger patients, as well as restenosis due to vessel growth requiring stent redilatations, often complicated by stent fractures. Data from long-term follow-up showed that, in younger patients, stress-related hypertension was more frequent. Conclusions. The procedure was immediately safe and effective in both groups. Pediatric patients must be accurately selected before stenting because they could probably need reinterventions and stents could impact on their future therapeutic perspectives.

  17. Gastrointestinal stenting

    International Nuclear Information System (INIS)

    Zollikofer, C.L.; Schoch, E.; Jost, R.; Decurtins, M.

    2000-01-01

    Acute obstructions of the gastric outlet, the duodenum, or the large bowel require rapid treatment to relieve symptoms of retention or ileus. Large-caliber stents of 16 to 22 mm offer a new non-surgical alternative for treating these patients with minimal risks and high success rates. For gastroduodenal outlet obstructions palliated by self-expanded metal stents, clinical success rates are in the range of 80-100 %. Preoperative treatment of colorectal obstructions successfully relieves acute symptoms of ileus in 87-100 % allowing primary anastomosis and thereby reducing the costs caused by multiple operations and the need of intensive care by approximately 25 %. It is the purpose of this review to familiarize the reader with the indications, possibilities, and limits of intestinal stenting. (orig.)

  18. A novel self-expanding interwoven nitinol stent for complex femoropopliteal lesions: 24-month results of the SUPERA SFA registry.

    Science.gov (United States)

    Scheinert, Dierk; Grummt, Lars; Piorkowski, Michael; Sax, Jacqueline; Scheinert, Susanne; Ulrich, Matthias; Werner, Martin; Bausback, Yvonne; Braunlich, Sven; Schmidt, Andrej

    2011-12-01

    To examine the efficacy and integrity of a novel interwoven self-expanding nitinol stent system for the treatment of complex femoropopliteal lesions in a "real world" medical practice. This retrospective analysis included 107 consecutive patients (77 men; mean age 68.9 years) with atherosclerotic femoropopliteal lesions (occlusions in 31%) who underwent implantation of 137 SUPERA stents. The patients were followed for up to 24 months by Doppler ultrasound examinations, radiography of the stent, and assessments of Rutherford-Becker class and ankle-brachial index (ABI). The mean implanted stent length was 111±50 mm (range 40-270). Procedure success (residual stenosis <30%) was achieved in 99% of procedures. The 6-, 12-, and 24-month cumulative primary patency rates (± standard error) were 93.1%±2.5%, 84.7%±3.6%, and 76.1%±4.5%, respectively, and the secondary patency rates were 99.0%±0.1%, 94.8%±0.2% and 91.9%±0.3%, respectively. Between baseline and 24 months, mean ABI increased from 0.68±0.14 to 0.87±0.10 and the mean Rutherford-Becker class decreased from 3.3±0.7 to 2.0±1.0 (p<0.0001 for both). Radiographs performed in 91 patients at a mean of 16.8±7.0 months found no stent fractures. Over a 2-year surveillance period, excellent durability without stent fractures was documented after implantation of the SUPERA stent in complex femoropopliteal lesions. In addition, significant improvements were observed in symptom classification and hemodynamics.

  19. Third-generation zotarolimus-eluting and everolimus-eluting stents in all-comer patients requiring a percutaneous coronary intervention (DUTCH PEERS): a randomised, single-blind, multicentre, non-inferiority trial.

    Science.gov (United States)

    von Birgelen, Clemens; Sen, Hanim; Lam, Ming Kai; Danse, Peter W; Jessurun, Gillian A J; Hautvast, Raymond W M; van Houwelingen, Gert K; Schramm, Alexander R; Gin, R Melvyn Tjon Joe; Louwerenburg, Johannes W; de Man, Frits H A F; Stoel, Martin G; Löwik, Marije M; Linssen, Gerard C M; Saïd, Salah A M; Nienhuis, Mark B; Verhorst, Patrick M J; Basalus, Mounir W Z; Doggen, Carine J M; Tandjung, Kenneth

    2014-02-01

    Third-generation, permanent-polymer-based drug-eluting stents with novel, flexible designs might be more easily delivered than previous generations of stents in complex coronary lesions, but might be less longitudinally stable. We aimed to assess the safety and efficacy in all-comer patients of two third-generation stents that are often used clinically, but that have not yet been compared, and one of which has not previously been assessed in a randomised trial. In this investigator-initiated, single-blind, multicentre, randomised, two-arm, non-inferiority trial, patients aged 18 years and older who required a percutaneous coronary intervention with implantation of a drug-eluting stent were recruited from four study sites in the Netherlands. We randomly assigned patients by independently managed computer-generated allocation sequences in a 1:1 ratio to receive either cobalt-chromium-based zotarolimus-eluting stents (Resolute Integrity, Medtronic, Santa Rosa, CA, USA) or platinum-chromium-based everolimus-eluting stents (Promus Element, Boston Scientific, Natick, MA, USA). Patients and analysts were masked to the allocated stent, but treating clinicians were not. The primary endpoint of target-vessel failure was a composite of safety (cardiac death or target-vessel-related myocardial infarction) and efficacy (target-vessel revascularisation) at 12 months, analysed by intention to treat (with a non-inferiority margin of 3·6%). This trial is registered with ClinicalTrials.gov, number NCT01331707. Between Nov 25, 2010, and May 24, 2012, 1811 eligible all-comer patients, with 2371 target lesions, were enrolled in the study. 370 (20%) patients presented with ST-elevation myocardial infarction and 447 (25%) with non-ST-elevation myocardial infarction. 906 patients were assigned to receive zotarolimus-eluting stents and 905 to receive everolimus-eluting stents. Ease of stent delivery was shown by very low numbers of patients requiring treatment other than their assigned

  20. Biomimicry, vascular restenosis and coronary stents.

    Science.gov (United States)

    Schwartz, R S; van der Giessen, W J; Holmes, D R

    1998-01-01

    Biomimicry is in its earliest stages and is being considered in the realm of tissue engineering. If arterial implants are to limit neointimal thickening, purely passive structures cannot succeed. Bioactivity must be present, either by pharmacologic intervention or by fabricating a 'living stent' that contains active cellular material. As tissue engineering evolves, useful solutions will emerge from applying this knowledge directly to vascular biologic problems resulting from angioplasty, stenting, and vascular prosthesis research.

  1. Assessing outcomes to determine whether symptoms related to hypertension justify renal artery stenting.

    Science.gov (United States)

    Modrall, J Gregory; Rosero, Eric B; Timaran, Carlos H; Anthony, Thomas; Chung, Jayer; Valentine, R James; Trimmer, Clayton

    2012-02-01

    The goal of the study was to determine the blood pressure (BP) response to renal artery stenting (RAS) for patients with hypertension urgency, hypertension emergency, and angina with congestive heart failure (angina/congestive heart failure [CHF]). Patients who underwent RAS for hypertension emergencies (n = 13), hypertension urgencies (n = 25), and angina/CHF (n = 14) were included in the analysis. By convention, hypertension urgency was defined by a sustained systolic BP ≥ 180 mm Hg or diastolic BP ≥ 120 mm Hg, while the definition of hypertension emergency required the same BP parameters plus hypertension-related symptoms prompting hospitalization. Patient-specific response to RAS was defined according to modified American Heart Association reporting guidelines. The study cohort of 52 patients had a median age of 66 years (interquartile range 58-72). The BP response to RAS varied significantly according to the indication for RAS. Hypertension emergency provided the highest BP response rate (85%), while the response rate was significantly lower for hypertension urgency (52%) and angina/CHF (7%; P = .03). Only 1 of 14 patients with angina/CHF was a BP responder. Multivariate analysis showed that hypertension urgency or emergency were not independent predictors of BP response to RAS. Instead, the only independent predictor of a favorable BP response was the number of preoperative antihypertensive medications (odds ratio 7.5; 95% confidence interval 2.5-22.9; P = .0004), which is another indicator of the severity of hypertension. Angina/CHF was an independent predictor of failure to respond to RAS (odds ratio 118.6; 95% confidence interval 2.8-999.9; P = .013). Hypertension urgency and emergency are clinical manifestations of severe hypertension, but the number of preoperative antihypertensive medications proved to be a better predictor of a favorable BP response to RAS. In contrast, angina/CHF was a predictor of failure to respond to stenting, providing further

  2. 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.

  3. 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...... the national databases. The Academic Research Consortium definition of ST was used. RESULTS: The DES were implanted in 3,548 patients (5,422 lesions) and BMS were implanted in 8,847 patients (11,730 lesions). Definite, probable, or possible ST was found in 190 (2.15%) patients in the BMS group and in 64 (1...

  4. Endothelial Barrier Protein Expression in Biodegradable Polymer Sirolimus-Eluting Versus Durable Polymer Everolimus-Eluting Metallic Stents.

    Science.gov (United States)

    Mori, Hiroyoshi; Cheng, Qi; Lutter, Christoph; Smith, Samantha; Guo, Liang; Kutyna, Matthew; Torii, Sho; Harari, Emanuel; Acampado, Eduardo; Joner, Michael; Kolodgie, Frank D; Virmani, Renu; Finn, Aloke V

    2017-12-11

    This study sought to investigate endothelial coverage and barrier protein expression following stent implantation. Biodegradable polymer drug-eluting stents (BP-DES) have been purported to have biological advantages in vessel healing versus durable polymer DES (DP-DES), although clinical trial data suggest equipoise. Biodegradable polymer-sirolimus-eluting stents (BP-SES), durable polymer-everolimus-eluting stents (DP-EES), and bare-metal stents (BMS) were compared. In the rabbit model (28, 45, and 120 days), stented arteries underwent light microscopic analysis and immunostaining for the presence of vascular endothelium (VE)-cadherin, an endothelial barrier protein, and were subjected to confocal microscopy and scanning electron microscopy. A cell culture study in stented silicone tubes was performed to assess cell proliferation. Light microscopic assessments were similar between BP-SES and DP-EES. BMS showed nearly complete expression of VE-cadherin at 28 days, whereas both DES showed significantly less with results favoring BP-SES versus DP-EES (39% coverage in BP-SES, 22% in DP-EES, 95% in BMS). Endothelial cell morphologic patterns differed according to stent type with BMS showing a spindle-like shape, DP-EES a cobblestone pattern, and BP-SES a shape in between. VE-cadherin-negative areas showed greater surface monocytes regardless of type of stent. Cell proliferation was suppressed in both DES with numerically less suppression in BP-SES versus DP-EES. This is the first study to examine VE-cadherin expression after DES. All DES demonstrated deficient barrier expression relative to BMS with results favoring BP-SES versus DP-EES. These findings may have important implications for the development of neoatherosclerosis in different stent types. Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  5. Drug-eluting stents in renal artery stenosis

    Energy Technology Data Exchange (ETDEWEB)

    Zaehringer, M. [Marienhospital Stuttgart, Department of Radiology, Stuttgart (Germany); Pattynama, P.M.T. [Erasmus MC-University Medical Center Rotterdam, Rotterdam (Netherlands); Talen, A. [genae associates nv, Antwerp (Belgium); Sapoval, M. [Hopital Europeen Georges Pompidou, Service de Radiologie Cardio-Vasculaire, Paris (France); Inserm U 780 epidemiologie Cardio Vasculaire, Paris (France)

    2008-04-15

    Because of higher acute and long-term success rates compared with balloon angioplasty alone, percutaneous stent implantation has become an accepted therapy for the treatment of atherosclerotic renal artery stenosis. Restenosis rates after successful renal stent placement vary from 6 up to 40%, depending on the definition of restenosis, the diameter of the treated vessel segment and comorbidities. The safety and efficacy of drug-eluting stents for the treatment of renal-artery stenosis is poorly defined. The recently published GREAT study is the only prospective study, comparing bare-metal and sirolimus-coated low profile stent systems in renal artery stenosis, showing a relative risk reduction of angiographic binary in-stent restenosis by 50%. This is an opinion paper on indications, current treatment options and restenosis rates following renal artery stenting and the potential use of drug-eluting stents for this indication. (orig.)

  6. Intravascular ultrasound-guided optimized stent deployment. Immediate and 6 months clinical and angiographic results from the Multicenter Ultrasound Stenting in Coronaries Study (MUSIC Study)

    Science.gov (United States)

    de Jaegere, P; Mudra, H; Figulla, H; Almagor, Y; Doucet, S; Penn, I; Colombo, A; Hamm, C; Bartorelli, A; Rothman, M; Nobuyoshi, M; Yamaguchi, T; Voudris, V; DiMario, C; Makovski, S; Hausmann, D; Rowe, S; Rabinovich, S; Sunamura, M; van Es, G A

    1998-08-01

    A study was set up to validate the safety and feasibility of intravascular ultrasound-guided stenting without subsequent anticoagulation, and its impact on the 6 months restenosis rate. The study was designed to be multicentred, prospective, and observational. One hundred and sixty-one patients with stable angina and a de novo coronary artery lesion were enrolled. In four patients, the implantation of a Palmaz-Schatz (with spiral bridge) stent had failed. One of these four patients died 3 days following bypass surgery. In two other patients, intravascular ultrasound assessment was not performed. One hundred and twenty-five of the remaining 155 patients (81%) were treated with aspirin (100 mg x day(-1)), because all three criteria for optimized stent expansion were met. Twenty-two of the remaining 38 patients (25%), in whom at least one criterion was not met were treated with aspirin and acenocoumarol (3 months, INR 2.5-3.5), while 16 patients only received aspirin. Stent thrombosis was documented in two patients (1.3%) for which repeat angioplasty was performed. During the hospital stay, there were no deaths or Q-wave myocardial infarctions. Five patients (3.2%) sustained a non-Q-wave myocardial infarction. During the follow-up period (198+/-38 days, complete for all patients, except one), one patient (0.6%) sustained a Q-wave myocardial infarction, one (0.6%) underwent bypass surgery, and repeat angioplasty was performed in nine patients (5.7%). In two of the nine patients, repeat angioplasty involved another lesion. Therefore, the target lesion revascularization rate during follow-up was 4.5% (seven patients). At quantitative coronary angiography, the minimal lumen diameter (mean+/-SD) increased from 1.12+/-0.34 mm before to 2.89+/-0.35 mm after stenting. Repeat angiography at 6 months was performed in 144 patients (92%). The minimal lumen diameter at follow-up was 2.12+/-0.67 mm. Restenosis (diameter stenosis of 50% or more) was documented in 12 patients or 8

  7. Multiple stent delivery system Multi-LOC, a new technology for spot-stenting of the femoropopliteal artery - proof of concept study in a preclinical large animal model.

    Science.gov (United States)

    Sigl, Martin; Dudeck, Oliver; Jung, Johannes; Koelble, Heinz; Amendt, Klaus

    2017-10-01

    A new stent system was studied in a porcine model to evaluate its feasibility for spot-stenting of the femoropopliteal artery. In a preliminary study in a single pig, handling and mechanical features of the novel multiple stent delivery system were tested. The Multi-LOC system demonstrated great feasibility regarding its pushability, trackability, and crossability. Excellent visibility of the individual stents allowed exact anatomically controlled implantation. In our main study, four to five short Multi-LOC stents (13 mm long) were implanted into the femoropopliteal arteries of six domestic pigs and long (60 to 100 mm) self-expandable nitinol stents were implanted into the same target vessel contralaterally to allow for intraindividual comparison. After four weeks survival under dual antiplatelet treatment, control angiography was performed. The animals were euthanized, stented vessels were explanted, and histologic sections were examined for the presence of neointimal formation. Multi-LOC stents demonstrated no occlusion of the femoropopliteal axis (0 vs. 1 occlusion distal to a control stent), no stent fractures (0 out of 26 vs. 2 out of 6 control stents), and lower percentage diameter stenosis (0.564 ± 0.056 vs. 0.712 ± 0.089; p = 0.008) and length of stenosis (19.715 ± 5.225 vs. 39.397 ± 11.182; p = 0.007) compared to a standard control stent, which was similar in total length to the multiple stented artery segment. Histological examination confirmed myointimal hyperplasia underlying in-stent stenosis. The multiple stent delivery system was studied in a porcine model, which demonstrated its feasibility. Preclinical experience revealed favourable results concerning stent fracture, restenosis, and patency of spot-stented femoropopliteal arteries.

  8. Functional comparison between BuMA Supreme biodegradable polymer sirolimus-eluting and durable polymer zotarolimus-eluting coronary stents using Quantitative Flow Ratio: PIONEER QFR substudy

    NARCIS (Netherlands)

    Asano, Taku; Katagiri, Yuki; Collet, Carlos; Tenekecioglu, Erhan; Miyazaki, Yosuke; Sotomi, Yohei; Amoroso, Giovanni; Aminian, Adel; Brugaletta, Salvatore; Vrolix, Mathias; Hernandez-Antolín, Rosana; van de Harst, Pim; Iñiguez, Andres; Janssens, Luc; Smits, Pieter; Wykrzykowska, Joanna J.; Ribeiro, Vasco Gama; Periera, Helder; da Silva, Pedro Canas; Piek, Jan J.; Reiber, Johan H. C.; von Birgelen, Clemens; Sabaté, Manel; Onuma, Yoshinobu; Serruys, Patrick W.

    2017-01-01

    Quantitative Flow Ratio (QFR) based on 3-dimensional quantitative coronary angiography (3D-QCA) is a novel method to assess the physiological functionality after treatment with stents. The current study aimed to evaluate the difference in physiological functionality 9 months after implantation of a

  9. Bioresorbable vascular scaffold (BVS) for in-stent chronic total occlusion: Antegrade recanalization and IVUS-guided BVS implantation by radial access

    Energy Technology Data Exchange (ETDEWEB)

    Medda, Massimo [Interventional Cardiology Unit, Istituto Clinico Sant' Ambrogio, Milano (Italy); Casilli, Francesco, E-mail: frcasill@tin.it [Interventional Cardiology Unit, Istituto Clinico Sant' Ambrogio, Milano (Italy); Bande, Marta [Interventional Cardiology Unit, Istituto Clinico Sant' Ambrogio, Milano (Italy); Latini, Maria Giulia [Cardiologia Interventistica, IRCCS Policlinico San Donato, San Donato Milanese, Milano (Italy); Ghommidh, Mehdi [Interventional Cardiology Unit, Istituto Clinico Sant' Ambrogio, Milano (Italy); Del Furia, Francesca [Unità Operativa di Cardiologia, Azienda Ospedaliera di Melegnano, Milano (Italy); Inglese, Luigi [Interventistica Cardiovascolare, Gruppo Sanitario Policlinico di Monza, Milano (Italy)

    2016-01-15

    The completely absorbable stents represent one of the latest innovations in the field of interventional cardiology, prospecting the possibility of “vascular repair”. In the published trials (ABSORB Cohort A and B, ABSORB EXTEND, and ABSORB II, III and IV) chronic total occlusions (CTOs) were considered an exclusion criteria. More recently the CTO-ABSORB pilot study demonstrated the safety and feasibility of bioresorbable vascular scaffold (BVS) use in case of CTO recanalization. We present the first case, to our knowledge, of in-stent occlusion successfully treated with an everolimus-eluting BVS and discuss its potential advantages in such kind of lesions.

  10. Routine intraoperative stenting for renal transplant recipients.

    Science.gov (United States)

    Wilson, Colin H; Bhatti, Aftab A; Rix, David A; Manas, Derek M

    2005-10-15

    Major urological complications (MUCs) after kidney transplantation contribute to patient morbidity and compromise graft function. Ureteric stents have been successfully used to treat such complications and a number of centers have adopted a policy of universal prophylactic stenting, at the time of graft implantation, to reduce the incidence of urine leaks and ureteric stenosis. In conjunction with the Cochrane Renal Group we searched the Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, reference lists of articles, books and abstracts and contacted companies, authors and experts to identify randomized controlled trials examining the use of stents in renal transplantation. The primary outcome was the incidence of MUCs and data on this statistic was pooled and analyzed using a random effects model. Seven randomized controlled trials (1154 patients) of low or moderate quality were identified. The incidence of MUCs was significantly reduced (relative risk [RR] 0.24; 95% CI: 0.07 - 0.77; P=0.02; number needed to treat = 13) by prophylactic ureteric stenting. Urinary tract infections were more common in stented patients (RR 1.49), unless the patients were prescribed 480 mg cotrimoxazole once daily. With this antibiotic regime the incidence of infection was equivalent between the two groups (RR 0.97). Stents appeared generally well tolerated, although trials using longer stents (> or = 20 cm) for longer periods of time (>6 weeks) reported more problems with encrustation and migration. Universal prophylactic stenting reduces the incidence of MUCs and should be recommended on the basis of currently available randomized controlled trials.

  11. From histology and imaging data to models for in-stent restenosis

    NARCIS (Netherlands)

    Amatruda, C.M.; Bona Casas, C.; Keller, B.K.; Tahir, H.; Dubini, G.; Hoekstra, A.; Hose, D.R.; Lawford, P.; Migliavacca, F.; Narracott, A.J.; Gunn, J.

    2014-01-01

    The implantation of stents has been used to treat coronary artery stenosis for several decades. Although stenting is successful in restoring the vessel lumen and is a minimally invasive approach, the long-term outcomes are often compromised by in-stent restenosis (ISR). Animal models have provided

  12. Drug-eluting stents vs bare metal stents for the treatment of large coronary vessels.

    Science.gov (United States)

    Quizhpe, Arturo R; Feres, Fausto; de Ribamar Costa, José; Abizaid, Alexandre; Maldonado, Galo; Costa, Ricardo; Abizaid, Andrea; Cano, Manuel; Moreira, Adriana C; Staico, Rodolfo; Mattos, Luiz Alberto; Tanajura, Luiz Fernando; Chaves, Aurea; Centemero, Marinella; Sousa, Amanda M R; Sousa, J Eduardo M R

    2007-08-01

    Lately drug-eluting stents (DES) have dramatically reduced restenosis rates and need for repeat revascularization in a wide subset of lesion and patients. However, their benefit for the treatment of large vessels (> 3.0 mm) has yet to be established. We investigated whether DES are superior to bare metal stents (BMS) in terms of clinical outcomes for the treatment of large coronary vessels. This study assessed the long-term outcomes (cardiac death, acute myocardial infarction, and need for repeat intervention in the treated vessel) of patients treated with either a DES (Cypher and Taxus) or a BMS of > or = 3.5 mm in diameter. A total of 250 consecutive patients who underwent DES implantation were clinically followed for 1 year and compared to 250 patients who were treated with BMS. Interventions in the setting of acute ST elevation myocardial infarction and treatment of bypass grafts were excluded. Cypher was the DES deployed in 70.8% of cases. Most of the enrolled patients were men (78%) with single vessel disease (65.6%). The left anterior descending artery was the culprit vessel in 34.2% of cases. Bare metal stent and DES cohorts had equivalent interpolated reference vessel diameter (3.19 +/- 0.3 mm for BMS vs 3.18 +/- 0.2 for DES; P = .1). Lesion was significantly longer in the group treated with DES (13.4 +/- 5.1 mm for BMS group vs 14.3 +/- 3.5 for DES; P = .0018). After 1 year of clinical follow-up, 95.2% of patients treated with DES and 91.2% of the patients who received BMS were free of major events (P = .2). A trend toward higher target-lesion revascularization was noticed in the group treated with BMS (4.8% vs 1.6%; P = .07). Percutaneous treatment of large coronary vessels carries a low risk of clinical events irrespective of the type of stent used.

  13. 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.

  14. Polymeric photosensitizer-embedded self-expanding metal stent for repeatable endoscopic photodynamic therapy of cholangiocarcinoma.

    Science.gov (United States)

    Bae, Byoung-chan; Yang, Su-Geun; Jeong, Seok; Lee, Don Haeng; Na, Kun; Kim, Joon Mee; Costamagna, Guido; Kozarek, Richard A; Isayama, Hiroyuki; Deviere, Jacques; Seo, Dong Wan; Nageshwar Reddy, D

    2014-10-01

    Photodynamic therapy (PDT) is a new therapeutic approach for the palliative treatment of malignant bile duct obstruction. In this study, we designed photosensitizer-embedded self-expanding nonvascular metal stent (PDT-stent) which allows repeatable photodynamic treatment of cholangiocarcinoma without systemic injection of photosensitizer. Polymeric photosensitizer (pullulan acetate-conjugated pheophorbide A; PPA) was incorporated in self-expanding nonvascular metal stent. Residence of PPA in the stent was estimated in buffer solution and subcutaneous implantation on mouse. Photodynamic activity of PDT-stent was evaluated through laserexposure on stent-layered tumor cell lines, HCT-116 tumor-xenograft mouse models and endoscopic intervention of PDT-stent on bile duct of mini pigs. Photo-fluorescence imaging of the PDT-stent demonstrated homogeneous embedding of polymeric Pheo-A (PPA) on stent membrane. PDT-stent sustained its photodynamic activities at least for 2 month. And which implies repeatable endoscopic PDT is possible after stent emplacement. The PDT-stent after light exposure successfully generated cytotoxic singlet oxygen in the surrounding tissues, inducing apoptotic degradation of tumor cells and regression of xenograft tumors on mouse models. Endoscopic biliary in-stent photodynamic treatments on minipigs also suggested the potential efficacy of PDT-stent on cholangiocarcinoma. In vivo and in vitro studies revealed our PDT-stent, allows repeatable endoscopic biliary PDT, has the potential for the combination therapy (stent plus PDT) of cholangiocarcinoma. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Angioplasty and Vascular Stenting

    Science.gov (United States)

    ... vessel. Covered stents or stent-grafts have additional advantages over bare stents and are becoming more commonly ... us improve RadiologyInfo.org by taking our brief survey: Survey Do you have a personal story about ...

  16. Computational Modeling to Predict Fatigue Behavior of NiTi Stents: What Do We Need?

    Science.gov (United States)

    Dordoni, Elena; Petrini, Lorenza; Wu, Wei; Migliavacca, Francesco; Dubini, Gabriele; Pennati, Giancarlo

    2015-01-01

    NiTi (nickel-titanium) stents are nowadays commonly used for the percutaneous treatment of peripheral arterial disease. However, their effectiveness is still debated in the clinical field. In fact a peculiar cyclic biomechanical environment is created before and after stent implantation, with the risk of device fatigue failure. An accurate study of the device fatigue behavior is of primary importance to ensure a successful stenting procedure. Regulatory authorities recognize the possibility of performing computational analyses instead of experimental tests for the assessment of medical devices. However, confidence in numerical methods is only possible after verification and validation of the models used. For the case of NiTi stents, mechanical properties are strongly dependent on the device dimensions and the whole treatments undergone during manufacturing process. Hence, special attention should be paid to the accuracy of the description of the device geometry and the material properties implementation into the numerical code, as well as to the definition of the fatigue limit. In this paper, a path for setting up an effective numerical model for NiTi stent fatigue assessment is proposed and the results of its application in a specific case study are illustrated. PMID:26011245

  17. Improved predictive value of GRACE risk score combined with platelet reactivity for 1-year cardiovascular risk in patients with acute coronary syndrome who underwent coronary stent implantation.

    Science.gov (United States)

    Li, Shan; Liu, Hongbin; Liu, Jianfeng; Wang, Haijun

    2016-11-01

    Both high platelet reactivity (HPR) and Global Registry of Acute Coronary Events (GRACE) risk score have moderate predictive value for major adverse cardiovascular disease (CVD) events in patients with acute coronary syndrome (ACS) who underwent percutaneous coronary intervention (PCI), whereas the prognostic significance of GRACE risk score combined with platelet function testing remains unclear. A total of 596 patients with non-ST elevation ACS who underwent PCI were enrolled. The P2Y 12 reaction unit (PRU) value was measured by VerifyNow P2Y 12 assay and GRACE score was calculated by GRACE risk 2.0 calculator. Patients were stratified by a pre-specified cutoff value of PRU 230 and GRACE score 140 to assess 1-year risk of cardiovascular death, non-fatal myocardial infarction (MI), and stent thrombosis. Seventy-two (12.1%) patients developed CVD events during 1-year follow-up. Patients with CVD events had a higher PRU value (244.6 ± 50.9 vs. 203.7 ± 52.0, p risk independently. Compared to patients with normal platelet reactivity (NPR) and GRACE score risk (HR: 5.048; 95% CI: 2.268-11.237; p risk score yielded superior risk predictive capacity beyond GRACE score alone, which is shown by improved c-statistic value (0.871, p = 0.002) as well as net reclassification improvement (NRI 0.263, p risk of adverse CVD events. The combination of platelet function testing and GRACE score predicted 1-year CVD risk better.

  18. Virtual Humans for Implantable Device Safety Assessment in MRI: Mitigating Magnetic Resonance Imaging Hazards for Implanted Medical Devices.

    Science.gov (United States)

    Brown, James E; Qiang, Rui; Stadnik, Paul J; Stotts, Larry J; Von Arx, Jeffrey A

    2017-01-01

    Magnetic resonance imaging (MRI) is the preferred modality for soft tissue imaging because of its nonionizing radiation and lack of contrast agent. Due to interactions between the MR system and active implantable medical devices (AIMDs), patients with implants such as pacemakers are generally denied access to MRI, which presents a detriment to that population. It has been estimated that 50-75% of patients with a cardiac device were denied access to MRI scanning and, moreover, that 17% of pacemaker patients need an MRI within 12 months of implantation [1]. In recent years, AIMD manufacturers, such as Biotronik, have assessed the conditional safety of devices in MRI.

  19. Natural history of intravascular ultrasound-detected edge dissections from coronary stent deployment.

    Science.gov (United States)

    Sheris, S J; Canos, M R; Weissman, N J

    2000-01-01

    High-resolution intravascular ultrasound (IVUS) performed immediately after stent deployment often reveals dissection at the stent margin that may not be appreciated by angiography. However, the natural history of these edge dissections is unknown. These intimal disruptions at the stent margins have been previously reported to occur in 5% to 23% of stent implantations. The short-term prognosis of these lesions appears to be good; however, the longer-term effect on restenosis and/or vessel remodeling is not known. We therefore studied a cohort of patients with the use of IVUS immediately after stent implantation and at 6 months to assess the incidence and prognosis of coronary edge dissections. One hundred fifty patients undergoing Palmaz-Shatz stent implantation were imaged with IVUS with the use of a motorized pullback, and the incidence of edge dissections was determined and graded according to depth and circumferential extent. Arterial and lesional morphometric parameters were assessed by digital planimetry. Six-month IVUS images were aligned with the poststent IVUS to determine the natural history of these lesions. Sixteen (10.7%) of 150 had edge tears. All were angiographically silent. Most lesions (n = 9) were superficial intimal tears. Vessel, lumen, and plaque area were similar in the nondissection and dissection groups in both the proximal and distal reference segments. Plaque eccentricity was likewise similar in both groups. At 6 months, lesions (n = 12) healed without a change in plaque burden, undergoing a "tacking down" process. Vessel area (19. 1 +/- 6.4 vs 18.4 +/- 7.1 mm(2), P = not significant), lumen area (8. 2 +/- 4.1 vs 9.2 +/- 4.0 mm(2), P = not significant), and plaque area (10.0 +/- 3.3 vs 9.8 +/- 3.3 mm(2), P = not significant) were unchanged when compared with the lesion site taken at stent deployment. Edge dissections as detected by IVUS do not necessarily proscribe an adverse prognosis at 6 months. This finding may provide reassurance to

  20. Glaukos iStent inject® Trabecular Micro-Bypass Implantation Associated with Cataract Surgery in Patients with Coexisting Cataract and Open-Angle Glaucoma or Ocular Hypertension: A Long-Term Study

    Directory of Open Access Journals (Sweden)

    Pedro Arriola-Villalobos

    2016-01-01

    Full Text Available Purpose. To evaluate the long-term efficacy and safety of the iStent inject device (Glaukos Corporation, Laguna Hills, CA combined with phacoemulsification in patients with coexistent cataract and open-angle glaucoma or ocular hypertension (OHT. Methods. A prospective, uncontrolled, nonrandomized, interventional case series study was conducted in patients with both mild or moderate open-angle glaucoma or OHT and cataract. Patients underwent cataract surgery along with the implant of two iStent inject devices. Outcome measures were intraocular pressure (IOP, topical hypotensive medications required, and best-corrected visual acuity (BCVA. Results. 20 patients were enrolled. Mean follow-up was 47.4±18.46 months. Mean baseline IOP was 19.95±3.71 mmHg with medication and 26±3.11 mmHg after washout. Mean end-follow-up IOP was 16.25±1.99 mmHg, representing an IOP decrease of 36.92%, 9.74±3.14 mmHg (P<0.001, from baseline washout IOP. The mean number of medications was significantly reduced from 1.3±0.66 to 0.75±0.79 (P=0.017. 45% of patients were medication-free by the end of follow-up. Mean log⁡MAR BCVA improved significantly from 0.42±0.16 to 0.18±0.16 (P<0.001. No complications of surgery were observed. Conclusion. The iStent inject device combined with cataract surgery served to significantly reduce both IOP and medication use in the long term in patients with coexistent open-angle glaucoma or ocular hypertension (OHT and cataract.

  1. Upper Gastrointestinal Stent

    OpenAIRE

    Kim, Sang Gyun; Yang, Chang-Hun

    2012-01-01

    Gastrointestinal (GI) stent has been developed for palliation of obstructive symptoms in various diseases causing obstruction of GI tract. Self-expanding metal stent (SEMS) has replaced old type of plastic stent, and endoscopic insertion of stent has replaced fluoroscopy-guided insertion. Nowadays, newly-designed SEMSs have been developed for prevention of complications such as stent migration and re-obstruction, and indications of stent recently have been widened into benign conditions as we...

  2. OCT guidance during stent implantation in primary PCI: A randomized multicenter study with nine months of optical coherence tomography follow-up

    Czech Academy of Sciences Publication Activity Database

    Kala, P.; Červinka, P.; Jakl, M.; Kanovský, J.; Kupec, A.; Špaček, R.; Kvasnak, M.; Poloczek, M.; Červinková, M.; Bezerra, H.; Valenta, Zdeněk; Attizzani, G.; Schnell, A.; Hong, L.; Costa, M.

    2018-01-01

    Roč. 250, 1 January (2018), s. 98-103 ISSN 0167-5273 Institutional support: RVO:67985807 Keywords : optical coherence tomography * OCT * primary PCI * ST-segment elevation myocardial infarction * drug -eluting stents Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery Impact factor: 6.189, year: 2016

  3. Retrospective assessment of survival rate for short endosseous dental implants.

    Science.gov (United States)

    Omran, Mohamed Tarek A; Miley, Douglas D; McLeod, Dwight E; Garcia, M Nathalia

    2015-04-01

    The aim of this study was to determine the survival rate of short implants that were placed in a residency program. In addition, the potential influence of diabetes, smoking, sinus grafting, guided bone regeneration, and implant type on survival was analyzed. Through a retrospective chart review, patient information and parameters for short implants being equal or less than 10 mm and regular implants being more than 10 mm were collected. The cumulative survival rate and implant and patient information from 213 consecutively placed implants from May 2002 through October 2011 were analyzed. The average survival time for short implants was 47.3 months, with a range of 6 to 141 months. The implant survival rate was 95.77% for short implants, which was not statistically significant from the regular implants. Smoking had a statistically significant negative effect on the survival rate of short implants. No statistical differences were found with implant survival rates for other factors. It can be concluded that short implants can be predictably placed in the mouth with a high survival rate and that smoking has a negative influence on the survival rate of the short implants.

  4. 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.

  5. Ausência de interação clopidogrel-estatina em pacientes submetidos a implante de "stent" coronário Ausencia de interacción clopidogrel-estatina en pacientes sometidos a implante de "Stent" coronario Lack of clopidogrel-statin interaction in patients undergoing coronary stent implantation

    Directory of Open Access Journals (Sweden)

    Carlos Vicente Serrano Júnior

    2010-09-01

    , niveles de P-selectina y glucoproteína IIb/IIIa (con y sin estímulo de ADP a través de citometría de flujo. Los resultados fueron analizados antes y después de la intervención coronaria percutánea y de la administración de clopidogrel. RESULTADOS: Observamos reducción de la actividad plaquetaria con uso de clopidogrel. Además de eso, no hubo diferencias entre las variables analizadas que comprobasen reducción de la actividad del clopidogrel cuando está asociado a las estatinas. Se observaron niveles de p-selectina (pre-angioplastia: 14,23±7,52 x 11,45±8,83 x 7,65±7,09; post angioplastia: 21,49±23,82 x 4,37±2,71 x 4,82±4,47, ρBACKGROUND: Some studies have suggested reduced activity of clopidogrel on platelet activation and adherence in patients using statins. OBJECTIVE: To assess whether platelet activation and aggregation decrease with clopidogrel, and whether there is a reduction of the action of clopidogrel when associated with atorvastatin or simvastatin. METHODS: This prospective study included 68 patients with stable angina with previous use of simvastatin, atorvastatin, or no statin (control group, with previous elective indication of percutaneous coronary intervention (PCI. Platelet activation was analyzed by means of platelet count, levels of P-selectin and glycoprotein IIb/IIIa (with and without ADP stimulation by flow cytometry. The findings were analyzed before and after percutaneous coronary intervention and the administration of clopidogrel. RESULTS: We observed reduction in platelet activity with use of clopidogrel. Furthermore, no differences were found between the variables analyzed to prove reduced activity of clopidogrel when combined with statins. We observed levels of p-selectin (pre-angioplasty: 14.23 ± 7.52 x 8.83 x 11.45 ± 7.65 ± 7.09; after angioplasty: 21.49 ± 23.82 x 4 37 ± 2.71 x 4.82 ± 4.47, ρ < 0.01 and glycoprotein IIb/IIIa (pre-angioplasty: 98.97 ± 0.43 ± 1.25 x 98.79 x 99.21 ± 0.40 after angioplasty: 99.37 ± 0

  6. Infolding of covered stents used for aortic coarctation: report of two cases.

    Science.gov (United States)

    Wan, Andrea W; Lee, Kyong-Jin; Benson, Lee N

    2014-01-01

    Covered stents have been used for the treatment of aortic coarctation to protect the arterial wall during dilation. Early results have shown them to be safe and effective. We report two cases of infolding of the proximal edge of a covered aortic coarctation stent. Management required implantation of a second stent. Poor stent apposition to the vessel wall and/or recoil may allow conditions for these events to occur. Copyright © 2013 Wiley Periodicals, Inc.

  7. Insertion Torques of Self-Drilling Mini-Implants in Simulated Mandibular Bone: Assessment of Potential for Implant Fracture.

    Science.gov (United States)

    Hosein, Yara K; Smith, Angie; Dunning, Cynthia E; Tassi, Ali

    2016-01-01

    Fracture of orthodontic mini-implants during insertion is a limiting factor for their clinical success. The purpose of this study was to determine the fracture potential of commonly used self-drilling orthodontic mini-implants when placed into simulated thick, dense mandibular bone. Six mini-implant systems were assessed for the potential for fracture (Aarhus, Medicon; Dual-Top, Jeil Medical; OrthoEasy, Forestadent; tomas-pin, Dentaurum; Unitek, 3M; and VectorTAS, Ormco). First, mini-implants were inserted manually, without predrilling, into bone substitutes (Sawbones) with a 3-mm-thick, dense (1.64 g/cm(3)) cortical layer. A custom-made insertion device was used for placement of mini-implants. A sixaxis force/torque transducer was secured at the base of the bone blocks to measure the maximum torque experienced during insertion. Measured insertion torques were compared with previously reported fracture torques, yielding a torque ratio (insertion torque as a percentage of fracture torque), which was used as an indicator of the potential for mini-implant fracture. Mini-implants that experienced torque ratios ≥ 75% upon insertion underwent further testing, following the manufacturer's recommendations for predrilling in thick, dense bone conditions. Significant differences in torque ratios were found among all mini-implants, except between OrthoEasy and Dual-Top, and OrthoEasy and VectorTAS. Overall, Aarhus had the highest torque ratio (91% ± 3%), with Unitek showing the lowest ratio (37% ± 3%). Aarhus and tomas-pin mini-implants displayed torque ratios ≥ 75% and experienced fracture upon insertion. When the manufacturer's specific predrilling recommendations were followed, no changes in torque ratio were found for Aarhus and tomas-pin. However, while Aarhus continued to fracture upon insertion, all tomas-pin mini-implants were inserted fully without fracture following predrilling. These findings support the safe use of Unitek, VectorTAS, Dual-Top, and Ortho

  8. Four-dimensional flow MRI of stented versus stentless aortic valve bioprostheses

    Energy Technology Data Exchange (ETDEWEB)

    Kesteren, Floortje van [University of Amsterdam, Department of Radiology and Nuclear Medicine, Academic Medical Centre, Amsterdam (Netherlands); University of Amsterdam, Department of Cardiology, Academic Medical Centre, Amsterdam (Netherlands); Wollersheim, Laurens W.; Kaya, Abdullah; Mol, Bas A. de [University of Amsterdam, Department of Cardiothoracic Surgery, Academic Medical Centre, Amsterdam (Netherlands); Baan, Jan; Boekholdt, S.M. [University of Amsterdam, Department of Cardiology, Academic Medical Centre, Amsterdam (Netherlands); Nederveen, A.J.; Ooij, Pim van; Planken, R.N. [University of Amsterdam, Department of Radiology and Nuclear Medicine, Academic Medical Centre, Amsterdam (Netherlands)

    2018-01-15

    To evaluate aortic velocity, wall shear stress (WSS) and viscous energy loss (EL) of stented and stentless bioprostheses using 4D flow MRI 1 year after surgical aortic valve replacement. For this cross-sectional study 28 patients with stented (n = 14) or stentless (n = 14) bioprosthesis underwent non-contrast-enhanced 4D-flow MRI at 1.5 T. Analyses included a comparison of velocity, WSS and EL in the ascending aorta during peak systole for both spatially averaged values and a comparison of local differences using per-voxel analysis. No significant differences were found in peak and mean velocity (stented vs. stentless: 2.45 m/s vs. 2.11 m/s; p = 0.09 and 0.60 m/s vs. 0.62 m/s; p = 0.89), WSS (0.60 Pa vs. 0.59 Pa; p = 0.55) and EL (10.17 mW vs. 7.82 mW; p = 0.10). Per-voxel analysis revealed significantly higher central lumen velocity, and lower outer lumen velocity, WSS and EL for stentless versus stented prostheses. One year after aortic valve implantation with stented and stentless bioprostheses, velocity, WSS and EL were comparable when assessed for averaged values in the ascending aorta. However, the flow profile described with local analysis for stentless prosthesis is potentially favourable with a significantly higher central velocity profile and lower values for outer lumen velocity, WSS and EL. (orig.)

  9. A Novel Stent Coated with Antibodies to Endoglin Inhibits Neointimal Formation of Porcine Coronary Arteries

    Directory of Open Access Journals (Sweden)

    Song Cui

    2014-01-01

    Full Text Available Endoglin/CD105 is an accessory protein of the transforming growth factor-β receptor system that plays a critical role in proliferation of endothelial cells and neovasculature. Here, we aimed to assess the effect of novel stents coated with antibodies to endoglin (ENDs on coronary neointima formation. Thirty ENDs, thirty sirolimus-eluting stents (SESs, and thirty bare metal stents (BMSs were randomly assigned and placed in the coronary arteries in 30 juvenile pigs. Histomorphometric analysis and scanning electron microscopy were performed after stent implantation. Our results showed that after 7 days, there was no difference in the neointimal area and percent area stenosis in ENDs compared with SMSs or BMSs. After 14 days, the neointima area and percent area stenosis in ENDs were markedly decreased than those in BMSs or SESs (P<0.05. Moreover, the percentage of reendothelialization was significantly higher in ENDs than that in SESs or BMSs (P<0.01 at 7 and 14 days. The artery injury and the inflammation scores were similar in all groups at 7 and 14 days. In conclusion, our results demonstrated for the first time to our knowledge that endoglin antibody-coated stents can markedly reduce restenosis by enhancing reendothelialization in the porcine model and potentially offer a new approach to prevent restenosis.

  10. Association of stent-induced changes in coronary geometry with late stent failure: Insights from three-dimensional quantitative coronary angiographic analysis.

    Science.gov (United States)

    Zhang, Bu Chun; Tu, Sheng Xian; Karanasos, Antonios; van Geuns, Robert-Jan; de Jaegere, Peter; Zijlstra, Felix; Regar, Evelyn

    2018-02-05

    The relationship between vessel angulation and large changes in vessel geometry after stent implantation and the occurrence of stent failure still remains unclear. We sought to investigate the association of the change in the coronary bending angle after stenting and the risk for late stent failure by three-dimensional quantitative coronary angiography (3D QCA). The bending angle in coronary lesions that presented with late stent failure and those without stent failure was computed during the cardiac cycle, before and after stenting using a recently developed 3D QCA software. A total of 40 lesions with stent failure (cases) were successfully matched to 47 lesions without stent failure (controls).The mean duration to follow-up coronary angiography was 1,011 days in cases and 1,109 days in the control group (P = 0.14). In stent failure, the systolic bending angle after stenting was smaller (14.45° [12.18, 17.68] versus 18.20° [14.00, 20.30], P = 0.01), while the stent-induced change in systolic bending angle was significantly larger (4.15° [1.13, 7.20] versus 1.80° [-1.90, 4.40], P = 0.004). Multivariable logistic regression analysis suggested that systolic bending angle after stenting (odds ratio: 0.88; 95% CI: 0.79-0.99; P = 0.03), and decrease in systolic bending angle after stenting (odds ratio: 1.13; 95% CI: 1.02-1.26; P = 0.03) were predictors of stent failure. Our study suggests that a change in the natural tortuous course of the coronaries by stent implantation with the decrease in coronary bending angle is a potentially major contributor in stent failure. © 2018 Wiley Periodicals, Inc.

  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. Primary endpoint results of the OMEGA Study: One-year clinical outcomes after implantation of a novel platinum chromium bare metal stent

    Energy Technology Data Exchange (ETDEWEB)

    Wang, John C., E-mail: john.wang@medstar.net [MedStar Union Memorial Hospital, Baltimore MD (United States); Carrié, Didier, E-mail: carrie.didier@chu-toulouse.fr [Centre Hôpital Universitaire Rangueil, Toulouse (France); Masotti, Monica, E-mail: MASOTTI@clinic.ub.es [Hospital Clinic, University of Barcelona (Spain); Erglis, Andrejs, E-mail: a.a.erglis@stradini.lv [Pauls Stradins Clinical University Hospital, University of Latvia, Riga (Latvia); Mego, David, E-mail: David.Mego@arheart.com [Arkansas Heart Hospital, Little Rock, AR (United States); Watkins, Matthew W., E-mail: Matthew.Watkins@vtmednet.org [University of Vermont Medical Center, Burlington VT (United States); Underwood, Paul, E-mail: Paul.underwood@bsci.com [Boston Scientific, Marlborough MA USA (United States); Allocco, Dominic J., E-mail: Dominic.allocco@bsci.com [Boston Scientific, Marlborough MA USA (United States); Hamm, Christian W., E-mail: C.Hamm@kerckhoff-klinik.de [Kerckhoff Heart and Thoraxcenter, Bad Nauheim (Germany)

    2015-03-15

    Background/purpose: Bare metal stents (BMS) have similar rates of death and myocardial infarction (MI) compared to drug-eluting stents (DES). DES lower repeat revascularization rates compared to BMS, but may have higher rates of late stent thrombosis (ST) potentially due to impaired endothelialization requiring longer dual anti-platelet therapy (DAPT). OMEGA evaluated a novel BMS designed to have improved deliverability and radiopacity, in comparison to currently available platforms. Methods/materials: OMEGA was a prospective, multicenter, single-arm study enrolling 328 patients at 37 sites (US and Europe). Patients received the OMEGA stent (bare platinum chromium element stent) for the treatment of de novo native coronary artery lesions (≤ 28 mm long; diameter ≥ 2.25 mm to ≤ 4.50 mm). The primary endpoint was 9-month target lesion failure (TLF: cardiac death, target vessel-related MI, target lesion revascularization [TLR]) compared to a prespecified performance goal (PG) based on prior generation BMS. All major cardiac events were independently adjudicated. DAPT was required for a minimum of 1 month post procedure. Results: In the OMEGA study, the mean age was 65; 17% had diabetes mellitus. The primary endpoint was met; 9 month TLF rate was 11.5%, and the upper 1-sided 95% confidence bound of 14.79% was less than the prespecified PG of 21.2% (p < 0.0001). One-year event rates were low including a TLF rate of 12.8% and an ST rate of 0.6% at 12 months. Conclusions: One-year outcomes of OMEGA show low rates of TLF, revascularization and ST. This supports safety and efficacy of the OMEGA BMS for the treatment of coronary artery disease. - Highlights: • The OMEGA study evaluated a novel platinum chromium bare metal stent. • OMEGA enrolled 328 patients at 37 sites (US and Europe). • The primary endpoint of 9 month target lesion failure was 11.5%. • One-year event rates were low including an ST rate of 0.6% at 12 months.

  13. Primary endpoint results of the OMEGA Study: One-year clinical outcomes after implantation of a novel platinum chromium bare metal stent

    International Nuclear Information System (INIS)

    Wang, John C.; Carrié, Didier; Masotti, Monica; Erglis, Andrejs; Mego, David; Watkins, Matthew W.; Underwood, Paul; Allocco, Dominic J.; Hamm, Christian W.

    2015-01-01

    Background/purpose: Bare metal stents (BMS) have similar rates of death and myocardial infarction (MI) compared to drug-eluting stents (DES). DES lower repeat revascularization rates compared to BMS, but may have higher rates of late stent thrombosis (ST) potentially due to impaired endothelialization requiring longer dual anti-platelet therapy (DAPT). OMEGA evaluated a novel BMS designed to have improved deliverability and radiopacity, in comparison to currently available platforms. Methods/materials: OMEGA was a prospective, multicenter, single-arm study enrolling 328 patients at 37 sites (US and Europe). Patients received the OMEGA stent (bare platinum chromium element stent) for the treatment of de novo native coronary artery lesions (≤ 28 mm long; diameter ≥ 2.25 mm to ≤ 4.50 mm). The primary endpoint was 9-month target lesion failure (TLF: cardiac death, target vessel-related MI, target lesion revascularization [TLR]) compared to a prespecified performance goal (PG) based on prior generation BMS. All major cardiac events were independently adjudicated. DAPT was required for a minimum of 1 month post procedure. Results: In the OMEGA study, the mean age was 65; 17% had diabetes mellitus. The primary endpoint was met; 9 month TLF rate was 11.5%, and the upper 1-sided 95% confidence bound of 14.79% was less than the prespecified PG of 21.2% (p < 0.0001). One-year event rates were low including a TLF rate of 12.8% and an ST rate of 0.6% at 12 months. Conclusions: One-year outcomes of OMEGA show low rates of TLF, revascularization and ST. This supports safety and efficacy of the OMEGA BMS for the treatment of coronary artery disease. - Highlights: • The OMEGA study evaluated a novel platinum chromium bare metal stent. • OMEGA enrolled 328 patients at 37 sites (US and Europe). • The primary endpoint of 9 month target lesion failure was 11.5%. • One-year event rates were low including an ST rate of 0.6% at 12 months

  14. [Finite Element Analysis of Intravascular Stent Based on ANSYS Software].

    Science.gov (United States)

    Shi, Gengqiang; Song, Xiaobing

    2015-10-01

    This paper adopted UG8.0 to bulid the stent and blood vessel models. The models were then imported into the finite element analysis software ANSYS. The simulation results of ANSYS software showed that after endothelial stent implantation, the velocity of the blood was slow and the fluctuation of velocity was small, which meant the flow was relatively stable. When blood flowed through the endothelial stent, the pressure gradually became smaller, and the range of the pressure was not wide. The endothelial shear stress basically unchanged. In general, it can be concluded that the endothelial stents have little impact on the flow of blood and can fully realize its function.

  15. Protein losing enteropathy secondary to a pulmonary artery stent

    Directory of Open Access Journals (Sweden)

    Narayanswami Sreeram

    2012-01-01

    Full Text Available A 2-year-old patient with hypoplastic left heart syndrome presented 6 months following Fontan completion with protein-losing enteropathy (PLE. He had undergone stent implantation in the left pulmonary artery after the Norwood procedure, followed by redilation of the stent prior to Fontan completion. Combined bronchoscopic and catheterization studies during spontaneous breathing confirmed left bronchial stenosis behind the stent, and diastolic systemic ventricular pressure during expiration of 25 mm Hg. We postulate that the stent acts as a valve, against which the patient generates high expiratory pressures, which are reflected in the ventricular diastolic pressure. This may be the cause of PLE.

  16. Rapid assessment of bilateral cochlear implantation for children in Kazakhstan.

    Science.gov (United States)

    Kosherbayeva, Lyazzat; Hailey, David; Kozhageldiyeva, Laura

    2014-10-01

    The aim of this study was to evaluate the effectiveness of bilateral cochlear implantation (CI) compared with unilateral CI for deaf children in the context of the Republic of Kazakhstan health system. Methods. A literature search was conducted, using the PubMed, Cochrane, and Embase data bases for studies that compared the effectiveness of bilateral and unilateral CI in children. The search included English language, publications from 2002-2012. Two reviewers independently evaluated all relevant studies. Administrative data relevant to CI in Kazakhstan were obtained from the Ministry of Health. Three relevant systematic reviews and an health technology assessment report were found. There was evidence of incremental benefits from bilateral CI but the quality of the available studies was poor and there was little information on longer term outcomes. No conclusions could be drawn regarding later incremental improvements to speech perception, learning, and quality of life. To date, in the Republic of Kazakhstan there is not full coverage of audiological screening due to the lack of medical equipment. This leads to late detection of hearing-impaired children and a long rehabilitation period, requiring more resources. Age of implantation in children is late and only a small minority attend general schools. The clinical effectiveness of bilateral CI, an expensive health technology, requires further study. Given the current situation in Kazakhstan with audiological screening and access to unilateral CI, there appeared to be other priorities for improving services for children with profound hearing impairment.

  17. Outcome of Sirolimus-Eluting Versus Zotarolimus-Eluting Coronary Stent Implantation in Patients With and Without Diabetes Mellitus (a SORT OUT III Substudy)

    DEFF Research Database (Denmark)

    Maeng, Michael; Jensen, Lisette O; Tilsted, Hans-Henrik

    2011-01-01

    Diabetes is associated with an increased risk of major adverse cardiac events after percutaneous coronary intervention. We compared clinical outcomes in patients with and without diabetes mellitus treated with the second-generation Endeavor zotarolimus-eluting stent (ZES) or the first......-generation Cypher Select+ sirolimus-eluting stent (SES). We randomized 2,332 patients to treatment with ZESs (n = 1,162, n = 169 diabetics) or SESs (n = 1,170, n = 168 diabetics) and followed them for 18 months. Randomization was stratified by presence/absence of diabetes. The primary end point was major adverse...... cardiac events defined as a composite of cardiac death, myocardial infarction, or target vessel revascularization. Secondary end points included these individual end points plus all-cause mortality and target lesion revascularization. In diabetic patients, use of ZES compared to SES was associated...

  18. In vitro assessment of primary stability of Straumann® implant designs.

    Science.gov (United States)

    Romanos, Georgios E; Ciornei, Gabriela; Jucan, Adina; Malmstrom, Hans; Gupta, Bhumija

    2014-02-01

    Primary implant stability (PS) is one of the main factors influencing implant survival rate. Several methods to determine the PS have been used, such as Periotest values (PVs) and resonance frequency analysis (RFA) with implant stability quotient (ISQ) values. The aim of this study was to compare different implant designs in regard to PS assessed by Periotest and RFA in vitro. A total of 90 implants were placed in freshly slaughtered cow ribs. The implants (Straumann®, Institute Straumann AG, Basel, Switzerland; length 10 mm, ø3.3 mm) had the following three designs: Bone Level (BL, 30 implants), Standard Plus (SP, 30 implants), and Tapered Effect (TE, 30 implants). Before implant placement, the investigator was calibrated for every design according to the manufacturer's instructions. An independent observer, blinded to the study, assessed the accuracy of placement. RFA based on the Osstell device and PVs were performed after abutment connection. One-way analysis of variance and Tukey's post hoc test were used for statistical evaluation. All implants were mechanically stable. The mean PV for BL was -4.67(± 1.18), for SP, -6.07(± 0.94), and for TE, -6.57(± 0.57). The mean ISQ values were 75.02(± 3.65), 75.98(± 3.00), and 79.83(± 1.85), respectively. The one-way ANOVA showed significant difference among three implant designs in PV (p < .0001) and for the ISQ between BL/TE or SP/TE implants (p < .0001). In addition, the Tukey's (pair-wise comparison) test showed significant differences in PV and RFA between the BL/T (p < .0001). Within the limitations of this study, higher implant stability was found for tapered designed implants. © 2012 Wiley Periodicals, Inc.

  19. The ankylos endosseous dental implant: assessment of stability up to 18 months with the Periotest.

    Science.gov (United States)

    Morris, H F; Winkler, S; Ochi, S

    2000-01-01

    Osseointegration is an ongoing histometric process that may vary during clinical function. The implant must be stable at uncovering, which reflects the status of bone-implant interface. The physiology of bone healing associated with endosseous implants suggests that this process occurs between 8 and 12 months, and Periotest values (PTVs) tend to reflect changes in the stability of the bone-implant interface. Stability generally increases gradually from the time of uncovering to an optimal PTV that occurs at a point close to 12 months. This stable interface must remain intact for long-term clinical survival. Rapid development of this optimal PTV is highly desirable in order to prevent premature overloading of the bone-implant interface. The Ankylos implant is a new screw-type implant design in which the thread pitch and length vary to maximize trabecular bone contact. The purpose of this report is to evaluate to 18 months the stability (PTVs) of this implant design. More than 457 implants were placed and followed for a period of 18 months by the multicentered, multidisciplinary Ankylos Implant Clinical Research Group (AICRG). Implant stability (PTVs) was assessed using the Periotest at abutment connection and at 3, 6, 9, 12, and 18 months after uncovering. The Periotest values for all implants rapidly reached an optimal status between uncovering (-3.1 PTVs) and 3 months (-3.4 PTVs). This rapid increase in stability has not previously been reported for other implant designs. The mandibular arch was more negative (-3.8 PTVs) at uncovering as compared with the PTVs for the maxillary arch (-1.7 PTVs). Negative PTVs were recorded (1) as length and diameter increased, (2) as bone density increased, (3) in certain jaw regions, (4) as the number of implants/case increased, and (5) for implants stabile at placement. The Ankylos screw implant design produced rapid stabilization 3 months after uncovering.

  20. Hemodynamics in Transplant Renal Artery Stenosis and its Alteration after Stent Implantation Based on a Patient-specific Computational Fluid Dynamics Model

    OpenAIRE

    Wang, Hong-Yang; Liu, Long-Shan; Cao, Hai-Ming; Li, Jun; Deng, Rong-Hai; Fu, Qian; Zhang, Huan-Xi; Fei, Ji-Guang; Wang, Chang-Xi

    2017-01-01

    Background: Accumulating studies on computational fluid dynamics (CFD) support the involvement of hemodynamic factors in artery stenosis. Based on a patient-specific CFD model, the present study aimed to investigate the hemodynamic characteristics of transplant renal artery stenosis (TRAS) and its alteration after stent treatment. Methods: Computed tomography angiography (CTA) data of kidney transplant recipients in a single transplant center from April 2013 to November 2014 were reviewed. Th...

  1. Pro-inflammatory cytokines at zirconia implants and teeth. A cross-sectional assessment.

    Science.gov (United States)

    Cionca, Norbert; Hashim, Dena; Cancela, Jose; Giannopoulou, Catherine; Mombelli, Andrea

    2016-11-01

    The aim of this study was to compare the expression of host-derived markers in peri-implant/gingival crevicular fluid (PCF/GCF) and clinical conditions at ceramic implants and contralateral natural teeth. As a secondary objective, we compared zirconia implants with titanium implants. One zirconia implant (ZERAMEX® Implant System) and one contralateral natural tooth were examined in 36 systemically healthy subjects (21 males, 15 females, mean age 58). The levels of Il-1β, Il-1RA, Il-6, Il-8, Il-17, b-FGF, G-CSF, GM-CSF, IFNɣ, MIP-1β, TNF-α, and VEGF were assessed in PCF/GCF using the Bio-Plex 200 Suspension Array System. The plaque index (PI), gingival index (GI), probing depth (PD), and bleeding on probing (BOP) were assessed at six sites around each implant or tooth. Titanium implants were also assessed when present (n = 9). The zirconia implants were examined after a loading period of at least 1.2 years (average 2.2 years). The mean PI was significantly lower at zirconia implants compared to teeth (p = 0.003), while the mean GI, PD, and BOP were significantly higher (p zirconia implants and teeth. The levels of IL-1β and TNF-α were significantly higher at zirconia implants than at teeth. No significant differences were found between zirconia and titanium implants. A correlation was found between the levels of IL-1RA, IL-8, GM-CSF, and MIP-1β at zirconia and titanium implants. The correlation in the expression of five biomarkers at zirconia implants and teeth, and of four biomarkers at zirconia and titanium implants, is compatible with the existence of a patient-specific inflammatory response pattern. Higher mean GI, PD, and BOP around implants suggests that the peri-implant mucosa may be mechanically more fragile than the gingiva. Similar expression of selected biomarkers at zirconia implants and teeth and at zirconia and titanium implants reflects existence of patient-specific inflammatory response patterns.

  2. Under X-ray guidance stent implantation through retrograde popliteal artery puncturing for the treatment of superficial femoral artery occlusion: the initial results in nine cases

    International Nuclear Information System (INIS)

    He Xu; Gu Jianping; Lou Wensheng; Chen Liang; Chen Guoping; Su Haobo; Song Jinhua; Wang Tao; Xu Ke

    2011-01-01

    Objective: To discuss the application of retrograde popliteal artery puncturing under X-ray guidance in the interventional therapy for superficial femoral artery occlusion. Methods: Retrograde popliteal artery puncturing under X-ray guidance was carried out in nine patients with long-segment occlusion of superficial femoral artery as antegrade recanalization via femoral artery approach had failed in them. After retrograde route was successfully established, the balloon dilation and subsequent stent placement for occluded vessel were performed. Results: The technical success was obtained in all patients. The occluded superficial femoral arteries were reopened and the symptoms of intermittent claudication disappeared. No serious complications such as injuries of adjacent nerves or vessels occurred. The ankle-brachial index (ABI) increased from preoperative (0.38±0.13) to postoperative (0.92±0.11) with the difference being statistically significant (P<0.01). A follow-up period lasting for 2-16 months was conducted. Eleven months after the treatment, intermittent claudication recurred in one case, and CT angiography showed that the distal part of the stent was narrowed. The symptoms were improved after percutaneous transcatheter angioplasty was performed again. Conclusion: Retrograde popliteal artery puncturing under X-ray guidance is an effective and safe technique for the treatment of superficial femoral artery long-segment occlusion with stent placement, especially for patients in whom antegrade recanalization via femoral artery approach fails. (authors)

  3. Measurement, simulation and uncertainty assessment of implant heating during MRI

    International Nuclear Information System (INIS)

    Neufeld, E; Kuehn, S; Kuster, N; Szekely, G

    2009-01-01

    The heating of tissues around implants during MRI can pose severe health risks, and careful evaluation is required for leads to be labeled as MR conditionally safe. A recent interlaboratory comparison study has shown that different groups can produce widely varying results (sometimes with more than a factor of 5 difference) when performing measurements according to current guidelines. To determine the related difficulties and to derive optimized procedures, two different generic lead structures have been investigated in this study by using state-of-the-art temperature and dosimetric probes, as well as simulations for which detailed uncertainty budgets have been determined. The agreement between simulations and measurements is well within the combined uncertainty. The study revealed that the uncertainty can be kept below 17% if appropriate instrumentation and procedures are applied. Optimized experimental assessment techniques can be derived from the findings presented herein.

  4. Measurement, simulation and uncertainty assessment of implant heating during MRI

    Energy Technology Data Exchange (ETDEWEB)

    Neufeld, E; Kuehn, S; Kuster, N [Foundation for Research on Information Technologies in Society (IT' IS), Zeughausstr. 43, 8004 Zurich (Switzerland); Szekely, G [Computer Vision Laboratory, Swiss Federal Institute of Technology (ETHZ), Sternwartstr 7, ETH Zentrum, 8092 Zurich (Switzerland)], E-mail: neufeld@itis.ethz.ch

    2009-07-07

    The heating of tissues around implants during MRI can pose severe health risks, and careful evaluation is required for leads to be labeled as MR conditionally safe. A recent interlaboratory comparison study has shown that different groups can produce widely varying results (sometimes with more than a factor of 5 difference) when performing measurements according to current guidelines. To determine the related difficulties and to derive optimized procedures, two different generic lead structures have been investigated in this study by using state-of-the-art temperature and dosimetric probes, as well as simulations for which detailed uncertainty budgets have been determined. The agreement between simulations and measurements is well within the combined uncertainty. The study revealed that the uncertainty can be kept below 17% if appropriate instrumentation and procedures are applied. Optimized experimental assessment techniques can be derived from the findings presented herein.

  5. Comparison of haemodialysis patients and non-haemodialysis patients with respect to clinical characteristics and 3-year clinical outcomes after sirolimus-eluting stent implantation: insights from the Japan multi-centre post-marketing surveillance registry.

    Science.gov (United States)

    Otsuka, Yoritaka; Ishiwata, Sugao; Inada, Tsukasa; Kanno, Hiroyuki; Kyo, Eisho; Hayashi, Yasuhiko; Fujita, Hiroshi; Michishita, Ichiro

    2011-04-01

    Long-term outcomes after sirolimus-eluting stent (SES) implantation in haemodialysis (HD) patients have remained controversial. We investigated the impact of HD on outcomes after SES implantation. We analysed the data on 2050 patients who underwent SES implantation in a multi-centre prospective registry in Japan. Three-year clinical outcomes were compared between the HD group (n = 106) and the non-haemodialysis (NH) group (n = 1944). At the 3-year clinical follow-up, the rates of unadjusted cardiac mortality (HD: 16.3 vs. NH: 2.3%) and target-lesion revascularization (TLR) (HD: 19.4 vs. NH: 6.6%) were significantly higher in the HD group than the NH group (P 2.0 vs. NH: 0.7%) did not reach statistical significance. Using Cox's proportional-hazard models with propensity score adjustment for baseline differences, the HD group had higher risks of TLR [HD: 16.3 vs. NH: 6.1%; hazard ratio, 2.83; 95% confidence interval (CI): 1.62-4.93, P = 0.0003] and cardiac death (HD: 12.3 vs. NH: 2.3%; hazard ratio, 5.51; 95% CI: 2.58-11.78, P < 0.0001). The consistent results of analyses, whether unadjusted or adjusted for other baseline clinical and procedural differences, identify HD as an independent risk factor for cardiac death and TLR. Percutaneous coronary intervention with SES in HD patients has a higher incidence of repeat revascularization and mortality compared with those in NH patients. Haemodialysis appears to be strongly associated with mortality and repeat revascularization even after SES implantation.

  6. Biodegradable urethral stents seeded with autologous urethral epithelial cells in the treatment of post-traumatic urethral stricture: a feasibility study in a rabbit model.

    Science.gov (United States)

    Fu, Wei-Jun; Zhang, Xu; Zhang, Bing-Hong; Zhang, Peng; Hong, Bao-Fa; Gao, Jiang-Ping; Meng, Bo; Kun, Hu; Cui, Fu-Zhai

    2009-07-01

    To evaluate the adhesion and growth of rabbit urethral epithelial cells (UECs) on a biodegradable unbraided mesh urethral stent, and to assess the feasibility and effect of the cell-seeded urethral stent for treating post-traumatic urethral stricture (PTUS) in a rabbit model. Rabbit UECs were collected by biopsy from adult rabbit urethra and seeded onto the outer layer of a mesh biodegradable urethral stent. The growth of UECs in cell-scaffolds was assessed by scanning electron microscopy, immunohistochemical and fluorescence staining. In all, 32 male New Zealand rabbits were used, with either PTUS or uninjured, as a control group. Cell-seeded stents were implanted into the rabbits strictured urethra. The histological and immunohistochemical findings were assessed after death at 1, 2, 8, 12 and 24 weeks, respectively. The reconstruction and function were evaluated by urethroscopy and retrograde urethrography. The cultured UECs adhered to the stent and grew well. Immunohistochemistry showed that the cells were stained positively for cytokeratin. At 4 weeks, vs 2 weeks, the thickness of the papillary projections of the epithelium decreased and inflammatory cell infiltration diminished. At 24 weeks the injured urethra was completely covered by integrated regeneration of three to five layers of urothelium. There was no evidence of voiding difficulty, stricture recurrence or other complications. The unbraided mesh biodegradable urethral stent with autologous UECs seemed to be feasible for treating PTUS in the rabbit urethra, and provides a hopeful avenue for clinical application allowing reconstruction of PTUS.

  7. In Vivo Collagen Remodeling in the Vascular Wall of Decellularized Stented Tissue-Engineered Heart Valves.

    Science.gov (United States)

    Ghazanfari, Samaneh; Driessen-Mol, Anita; Sanders, Bart; Dijkman, Petra E; Hoerstrup, Simon P; Baaijens, Frank P T; Bouten, Carlijn V C

    2015-08-01

    Decellularized tissue-engineered heart valves (TEHVs) are under investigation as alternative for current heart valve prostheses with the potential to rapidly repopulate with cells within the body. Ideally, these valves are stented for transapical or minimally invasive delivery. It is unclear if and how the matrix of these valves remodels under in vivo hemodynamic loading conditions and in the presence of a stent. Here, we study the evolution of collagen orientation and tissue maturation in the wall of stented decellularized TEHVs with time after implantation. In a previous study, stented TEHVs based on rapidly degrading scaffolds were cultured in bioreactors, decellularized, and transapically implanted as pulmonary valve replacement in sheep. In the present study, collagen (re)orientation in the initially isotropic valvular wall was assessed using a fluorescent collagen probe combined with confocal imaging and image analysis of explanted tissue at 8, 16, and 24 weeks following implantation. Collagen tortuosity or waviness in the explants, as a measure of matrix maturity, was quantified using a Gabor wavelet method and compared with tortuosity in native sheep vascular wall tissue. Results indicate that on the luminal side of the valvular wall, fibers became aligned in circumferential direction, while tortuosity increased with implantation time, showing striking similarities with the native collagen structure after 24 weeks. On the outside of the wall, where the engineered tissue touches the stent, collagen fibers in the vicinity of the struts aligned along the struts, whereas collagen fibers in between struts were randomly oriented. Immunohistochemistry was performed to evaluate the presence of elastin and collagen type I and III. After 8 weeks, collagen types I and III were mostly present at the luminal side of the wall, whereas at 16 and 24 weeks, a homogenous distribution of collagen I and III was observed throughout the wall. Elastin was mostly expressed at the

  8. Resolution of Metallic Biliary Stent Allergic Reaction After Partial Stent Removal in a Patient with Nickel Sensitivity.

    Science.gov (United States)

    Esparaz, Anthony M; Ahmed, Muneeb

    2017-07-01

    Local and systemic reactions to implanted metallic devices, particularly to those containing nickel, are well documented. Metal ions are released due to exposure of the metal to blood, proteins, other body fluids, and sheer mechanical stress. Metal ions then complex with native proteins and become antigens, which can elicit hypersensitivity reactions. Another case report depicts a specific allergic complication (early stent occlusion) related to metallic biliary stent implantation. We present a case of allergic symptoms, associated with eating, in a patient who developed nickel sensitivity after biliary metal stent placement confirmed by allergic skin testing to the same metallic biliary stent placed one year earlier. Symptoms resolved following partial removal of the non-epithelialized portion of the biliary stent.

  9. The effects of surface processing on in-vivo corrosion of Nitinol stents in a porcine model.

    Science.gov (United States)

    Sullivan, Stacey J L; Madamba, Daniel; Sivan, Shiril; Miyashiro, Katie; Dreher, Maureen L; Trépanier, Christine; Nagaraja, Srinidhi

    2017-10-15

    A major limitation with current assessments of corrosion in metallic medical devices is the lack of correlation between in-vitro and in-vivo corrosion performance. Therefore, the objective of this study was to elucidate the relationship between pitting corrosion measured by breakdown potentials (E b ) in ASTM F2129 testing and corrosion resistance in-vivo. Four groups of Nitinol stents were manufactured using different processing methods to create unique surface properties. The stents were implanted into iliac arteries of minipigs for six months and explanted for corrosion analysis. Scanning electron microscopy and energy dispersive X-ray spectrometry analyses indicated that stents with a thick complex thermal oxide (420nm) and high corrosion resistance in-vitro (E b =975±94mV) were free from detectable corrosion in-vivo and exhibited no changes in Ni/Ti ratio when compared to non-implanted controls. This result was also found in mechanically polished stents with a thin native oxide (4nm; E b =767±226mV). In contrast, stents with a moderately thick thermal oxide (130nm) and low corrosion resistance in-vitro (E b =111±63mV) possessed corrosion with associated surface microcracks in-vivo. In addition, Ni/Ti ratios in corroded regions were significantly lower compared to non-corroded adjacent areas on explanted stents. When stents were minimally processed (i.e. retained native tube oxide from the drawing process), a thick thermal oxide was present (399nm) with low in-vitro corrosion resistance (E b =68±29mV) resulting in extensive in-vivo pitting. These findings demonstrate that functional corrosion testing combined with a detailed understanding of the surface characteristics of a Nitinol medical device can provide insight into in-vivo corrosion resistance. Nitinol is a commonly used material in the medical device industry. However, correlations between surface processing of nitinol and in-vivo corrosion has yet to be established. Elucidating the link between in

  10. Geographical Difference of the Interaction of Sex With Treatment Strategy in Patients With Multivessel Disease and Left Main Disease: A Meta-Analysis From SYNTAX (Synergy Between PCI With Taxus and Cardiac Surgery), PRECOMBAT (Bypass Surgery Versus Angioplasty Using Sirolimus-Eluting Stent in Patients With Left Main Coronary Artery Disease), and BEST (Bypass Surgery and Everolimus-Eluting Stent Implantation in the Treatment of Patients With Multivessel Coronary Artery Disease) Randomized Controlled Trials.

    Science.gov (United States)

    Sotomi, Yohei; Onuma, Yoshinobu; Cavalcante, Rafael; Ahn, Jung-Min; Lee, Cheol Whan; van Klaveren, David; de Winter, Robbert J; Wykrzykowska, Joanna J; Farooq, Vasim; Morice, Marie-Claude; Steyerberg, Ewout W; Park, Seung-Jung; Serruys, Patrick W

    2017-05-01

    The impact of sex on clinical outcomes of percutaneous coronary intervention and coronary artery bypass graft for patients with multivessel coronary disease and unprotected left main disease could be dissimilar between Western and Asian populations. To assess clinical outcomes after percutaneous coronary intervention or coronary artery bypass graft in women and men with multivessel coronary disease and unprotected left main disease, a pooled analysis (n=3280) was performed using the patient-level data from 3 large randomized trials: SYNTAX (Synergy between PCI with Taxus and Cardiac Surgery), PRECOMBAT (Bypass Surgery Versus Angioplasty Using Sirolimus-Eluting Stent in Patients With Left Main Coronary Artery Disease), and BEST (Bypass Surgery and Everolimus-Eluting Stent Implantation in the Treatment of Patients with Multivessel Coronary Artery Disease) trials. The primary end point was all-cause death. Of 3280 patients, 794 patients (24.2%) were women. The median follow-up period was 1806 days (1611-1837 days). In women, a high heterogeneity of the treatment effect among the 3 trials was found for all-cause death ( I 2 >50%), whereas in men, it was consistent across the 3 trials. In the Western trial (SYNTAX), female sex favored coronary artery bypass graft compared with percutaneous coronary intervention (hazard ratio (percutaneous coronary intervention) 2.213; 95% confidence interval, 1.242-3.943; P =0.007), whereas in the Asian women (PRECOMBAT and BEST), the treatment effect was neutral between both strategies. Sex interaction with treatment strategy was evident in the Western trial ( P interaction =0.019) but not in the Asian trials (PRECOMBAT P interaction =0.469 and BEST P interaction =0.472; I 2 =58%). The present meta-analysis suggested the presence of the heterogeneous sex-treatment interaction across Asian and Western trials. Considering the ongoing globalization of our medical practice, the heterogeneity of the sex-treatment interaction needs to be

  11. Biocompatibility of coronary stent materials: effect of electrochemical polishing

    Energy Technology Data Exchange (ETDEWEB)

    Scheerder, I. de [University Hospital Leuven (Belgium). Dept. of Cardiology; Sohier, J.; Froyen, L.; Humbeeck, J. van [Louvain Univ. (Belgium). Dept. of Metallurgy and Materials Engineering; Verbeken, E. [University Hospital Leuven (Belgium). Dept. of Pathology

    2001-02-01

    Percutaneous Transluminal Coronary Revascularization (PTCR) is now a widely accepted treatment modality for atherosclerotic coronary artery disease. Current multicenter randomized trials comparing PTCR with the more invasive Coronary Artery Bypass Grafting could not show long-term significant survival differences. During the last two decades progress has been made to further optimize PTCR. The most logic approach to treat atherosclerotic coronary narrowings is to remove the atherosclerotic material using especially developed devices. Several trials, however, could not show a significant beneficial outcome after use of these devices compared to plain old balloon angioplasty. Another approach was to implant a coronary prothesis (stent), scaffolding the diseased coronary artery after PTCA. This approach resulted in a decreased restenosis rate at follow-up. The beneficial effects of stenting, however, was not found to be related to the inhibition of the neointimal cellular proliferation after vascular injury, but simply to be the mechanical result of overstretching of the treated vessel segment. The most important remaining clinical problem after stenting remains the neointimal hyperplasia within the stent, resulting in a significant stent narrowing in 13 to 30% of patients. Further efforts to improve the clinical results of coronary stenting should focus on the reduction of this neointimal hyperplasia. Neointimal hyperplasia after stent implantation results from (1) a healting response to the injury caused by the stent implantation and (2) a foreign body response to the stent itself. Factors that seem to influence the neointimal hyperplastic response are genetic, local disease related, stent delivery related and stent related factors. Biocompatibilisation of coronary stents by looking for more biocompatible metal alloys, optimized surface characteristics and optimized stent designs should result in a better late patency. Furthermore drug eluting and radioactive stents

  12. Finite element simulation of ultrasonic wave propagation in a dental implant for biomechanical stability assessment.

    Science.gov (United States)

    Vayron, Romain; Nguyen, Vu-Hieu; Bosc, Romain; Naili, Salah; Haïat, Guillaume

    2015-10-01

    Dental implant stability, which is an important parameter for the surgical outcome, can now be assessed using quantitative ultrasound. However, the acoustical propagation in dental implants remains poorly understood. The objective of this numerical study was to understand the propagation phenomena of ultrasonic waves in cylindrically shaped prototype dental implants and to investigate the sensitivity of the ultrasonic response to the surrounding bone quantity and quality. The 10-MHz ultrasonic response of the implant was calculated using an axisymetric 3D finite element model, which was validated by comparison with results obtained experimentally and using a 2D finite difference numerical model. The results show that the implant ultrasonic response changes significantly when a liquid layer is located at the implant interface compared to the case of an interface fully bounded with bone tissue. A dedicated model based on experimental measurements was developed in order to account for the evolution of the bone biomechanical properties at the implant interface. The effect of a gradient of material properties on the implant ultrasonic response is determined. Based on the reproducibility of the measurement, the results indicate that the device should be sensitive to the effects of a healing duration of less than one week. In all cases, the amplitude of the implant response is shown to decrease when the dental implant primary and secondary stability increase, which is consistent with the experimental results. This study paves the way for the development of a quantitative ultrasound method to evaluate dental implant stability.

  13. On the use of EMI for the assessment of dental implant stability

    Science.gov (United States)

    La Malfa Ribolla, Emma; Rizzo, Piervincenzo; Gulizzi, Vincenzo

    2014-03-01

    The achievement and the maintenance of dental implant stability are prerequisites for the long-term success of the osseointegration process. Since implant stability occurs at different stages, it is clinically required to monitor an implant over time, i.e. between the surgery and the placement of the artificial tooth. In this framework, non-invasive tests able to assess the degree of osseointegration are necessary. In this paper, the electromechanical impedance (EMI) method is proposed to monitor the stability of dental implants. A 3D finite element model of a piezoceramic transducer (PZT) bonded to a dental implant placed into the bone was created, considering the presence of a bone-implant interface subjected to Young's modulus change. The numerical model was validated experimentally by testing bovine bone samples. The EMI response of a PZT, bonded to the abutment screwed to implants inserted to the bone, was measured. To simulate the osseointegration process a pulp canal sealer was used to secure the implant to the bone. It was found that the PZT's admittance is sensitive to the stiffness variation of the bone-implant interface. The results show that EMIbased method is able (i) to evaluate the material properties around the implant, and (ii) to promote a novel non-invasive monitoring of dental implant surgical procedure.

  14. 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

  15. 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.

  16. 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.

  17. [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.

  18. Stenver's radiographic assessment of the multichannel cochlear implant

    Energy Technology Data Exchange (ETDEWEB)

    Kweon, Dae Cheol; Kim, Dong Sung [Seoul National University Hospital, Seoul (Korea, Republic of); Jung, Hong Ryang; Kim, Myeong Soo; Lim, Cheong Hwan; Kim Jeong Koo [Hanseo University, Seosan (Korea, Republic of); Park, Peom [Ajou University, Suwon (Korea, Republic of)

    2002-06-15

    To assess the new multichannel cochlear implant by radiography in Stenver's projection, because MRI generates artifacts, inducing an electrical current and causing device magnetization. CT is relatively expensive and the metal electrodes scatter the image. Multichannel cochlear implant insertion using the multichannel cochlear implant device. Patients underwent postoperative radiography of their implants. The radiographs were obtained in a Stenver's. The insertion depth of the implant was measured on the radiographs and the results were correlated with the surgical results of insertion depth and with audiometric tests. Patients a correct inserted electrode was found, while in patient complications concerning the electrode were noticed. Radiographs in the Senver's projection are sufficient for the postoperative assessment of the multichannel cochlear implant device and an exact evaluation of the insertion depth.

  19. Role of stent type and of duration of dual antiplatelet therapy in patients with chronic kidney disease undergoing percutaneous coronary interventions. Is bare metal stent implantation still a justifiable choice? A post-hoc analysis of the all comer PRODIGY trial.

    Science.gov (United States)

    Crimi, Gabriele; Leonardi, Sergio; Costa, Francesco; Adamo, Marianna; Ariotti, Sara; Valgimigli, Marco

    2016-06-01

    Chronic kidney disease (CKD) is a powerful predictor of major cardiovascular events and stent thrombosis (ST) in patients undergoing percutaneous coronary interventions (PCI). No randomized data are available to compare, and guide the selection of type of stent between bare metal (BMS) or drug eluting stent (DES) in this population. We performed a post-hoc analysis of the PROlonging Dual antiplatelet treatment after Grading stent-induced Intimal hyperplasia studY (PRODIGY) trial, in which stable or unstable patients with coronary artery disease undergoing PCI were randomized 1:1:1:1 to receive BMS, paclitaxel- (PES), zotarolimus- (ZES-S), or everolimus- (EES) eluting stent. A total of 2003 patients were randomized, and 22 patients were excluded for missing serum creatinine leading to a final population of 1981 patients. Primary outcome was definite or probable ST. We also assessed MACE (myocardial infarction, stroke, or death), and all-cause death, as secondary outcome. CKD, defined with estimated glomerular filtration rate <60ml/min/1.73m(2), was found in 373 patients (18.8%). The incidence of ST at 2years was 5.1% in CKD and 2.1% in non-CKD patients (HR 2.57, 95% confidence interval (CI) 1.46 to 4.52, p<0.001). At multivariable regression we found that patients randomized to EES or ZES-S, but not PES, had lower risk of ST at two years as compared with BMS: adjusted HR=0.288, 95% CI [0.107-0.778, p=0.014] and HR=0.394, 95% CI [0.164-0.947, p=0.037] respectively. The number of patients needed to be treated to prevent 1 ST with an EES vs BMS was 20 in CKD and 50 in patients without CKD. EES patients had the lowest incident MACE events 26.4% as compared to BMS 35.1%, ZES-S 33.0%, or PES 35.7% patients, p=0.551. All-cause death was lowest in ZES-S group 10.6% as compared to BMS 18.1%, PES 25.5% and EES 14.9%, p=0.040. We found no significant interaction between DAPT duration (6 vs 24months) and stent type on primary outcome, PINT=0.47 for BMS, PINT=0.57 for PES, PINT

  20. One-year outcomes of the U.S. and Japanese regulatory trial of the Misago stent for treatment of superficial femoral artery disease (OSPREY study).

    Science.gov (United States)

    Ohki, Takao; Angle, John F; Yokoi, Hiroyoshi; Jaff, Michael R; Popma, Jeffrey; Piegari, Guy; Kanaoka, Yuji

    2016-02-01

    The purpose of this study was to assess the safety and efficacy of the Misago stent (Terumo Corp, Tokyo, Japan) in occlusive and stenotic superficial femoral artery (SFA) disease. The safety and efficacy of the Misago SFA stent were evaluated prospectively in this initial collaboration trial between Japan and the United States. Because this trial enrolled patients mainly from Japan and the United States and because there is a question as to whether a race difference exists in SFA stent performance, the race difference on outcome was also analyzed. In addition, results were compared with a prior SFA stent trial. The Misago stent was implanted in 261 subjects with TransAtlantic Inter-Society Consensus (TASC) type A and type B SFA lesions (201 subjects in the United States, 50 in Japan, 9 in Taiwan, 1 in South Korea). The mean age of the patients was 69.3 ± 10.0 years, and the mean lesion length was 83.8 ± 41.3 mm. The overall 12-month primary patency rate and clinically driven target lesion revascularization were 82.9% and 13.0%, respectively. Regional differences within the Occlusive/Stenotic Peripheral Artery Revascularization Study (OSPREY) and outcomes between U.S. and Asian patients were similar, including primary patency (82.9% vs 83.0%; P = .889), clinically driven target lesion revascularization (13.4% vs 11.7%; P = .829), stent fracture rate (1.3% vs 0.0%; P = 1.000), and stent thrombosis rate (0.5% vs 0.0%; P = 1.000). OSPREY 12-month data showed satisfactory outcome of the Misago stent for the treatment of TASC type A and type B SFA lesions and appears to be comparable to recent stent trials. In addition, the lack of difference in outcome among races supports the value of international trials. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  1. A bioabsorbable everolimus-eluting coronary stent system for patients with single de-novo coronary artery lesions (ABSORB): a prospective open-label trial.

    Science.gov (United States)

    Ormiston, John A; Serruys, Patrick W; Regar, Evelyn; Dudek, Dariusz; Thuesen, Leif; Webster, Mark W I; Onuma, Yoshinobu; Garcia-Garcia, Hector M; McGreevy, Robert; Veldhof, Susan

    2008-03-15

    A fully bioabsorbable drug-eluting coronary stent that scaffolds the vessel wall when needed and then disappears once the acute recoil and constrictive remodelling processes have subsided has theoretical advantages. The bioasorbable everolimus-eluting stent (BVS) has a backbone of poly-L-lactic acid that provides the support and a coating of poly-D,L-lactic acid that contains and controls the release of the antiproliferative agent everolimus. We assessed the feasibility and safety of this BVS stent. In this prospective, open-label study we enrolled 30 patients who had either stable, unstable, or silent ischaemia and a single de-novo lesion that was suitable for treatment with a single 3.0 x 12 mm or 3.0 x 18 mm stent. Patients were enrolled from four academic hospitals in Auckland, Rotterdam, Krakow, and Skejby. The composite endpoint was cardiac death, myocardial infarction, and ischaemia-driven target lesion revascularisation. Angiographic endpoints were available for 26 patients and intravascular-ultrasound endpoints for 24 patients. Clinical endpoints were assessed in all 30 patients at 6 and 12 months. In a subset of 13 patients, optical coherence tomography was undertaken at baseline and follow-up. Analysis was by intention to treat. This study is registered with ClinicalTrials.gov, number NCT00300131. Procedural success was 100% (30/30 patients), and device success 94% (29/31 attempts at implantation of the stent). At 1 year, the rate of major adverse cardiac events was 3.3%, with only one patient having a non-Q wave myocardial infarction and no target lesion revascularisations. No late stent thromboses were recorded. At 6-month follow-up, the angiographic in-stent late loss was 0.44 (0.35) mm and was mainly due to a mild reduction of the stent area (-11.8%) as measured by intravascular ultrasound. The neointimal area was small (0.30 [SD 0.44] mm2), with a minimal area obstruction of 5.5%. This study shows the feasibility of implantation of the bioabsorbable

  2. Complex bifurcation lesions: Randomized comparison of a fully bioresorbable modified t stenting strategy versus bifurcation reconstruction with a dedicated self-expanding stent in combination with bioresorbable scaffolds, an OCT study: Rationale and design of the COBRA II trial.

    Science.gov (United States)

    Bennett, J; Adriaenssens, T; Desmet, W; Dubois, C

    2016-11-15

    There is an ongoing controversy regarding the efficacy and safety of different percutaneous stenting techniques for coronary bifurcation lesions needing >1 stent. The promise of safe vessel restoration with bioresorbable scaffolds (BRS) may not be transferable to complex double BRS bifurcation techniques, and permanent metallic scaffolding of the bifurcation core may be needed. We identified modified-T stenting as the most promising fully bioresorbable 2-stent strategy in a preclinical setting. The objective of this study is to assess acute performance and compare long-term vessel healing with this strategy, versus an approach combining BRS with a dedicated metallic drug-eluting bifurcation stent. In a single center, 60 consecutive patients with true and complex coronary bifurcation lesions will be randomly assigned to treatment with the dedicated self-expanding Axxess ™ biolimus-eluting bifurcation stent in the proximal main vessel and additional Absorb ™ everolimus-eluting BRS in the branches versus a modified T technique using Absorb ™ only. Angiography and optical coherence tomography (OCT) will be performed immediately after implantation and at 30 months, and clinical follow-up is foreseen up to 5 years after implantation. The primary endpoint is the change in minimal luminal area assessed with OCT from baseline to 30 months in pre-specified bifurcation segments. To date the use of Absorb ™ BRS in complex coronary bifurcations has not been evaluated in a randomized clinical trial setting. The COBRA II study will examine the role and safety of a double BRS strategy in coronary bifurcations, alone or in combination with a metallic dedicated bifurcation device. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  3. Statistical parametric mapping and statistical probabilistic anatomical mapping analyses of basal/acetazolamide Tc-99m ECD brain SPECT for efficacy assessment of endovascular stent placement for middle cerebral artery stenosis

    International Nuclear Information System (INIS)

    Lee, Tae-Hong; Kim, Seong-Jang; Kim, In-Ju; Kim, Yong-Ki; Kim, Dong-Soo; Park, Kyung-Pil

    2007-01-01

    Statistical parametric mapping (SPM) and statistical probabilistic anatomical mapping (SPAM) were applied to basal/acetazolamide Tc-99m ECD brain perfusion SPECT images in patients with middle cerebral artery (MCA) stenosis to assess the efficacy of endovascular stenting of the MCA. Enrolled in the study were 11 patients (8 men and 3 women, mean age 54.2 ± 6.2 years) who had undergone endovascular stent placement for MCA stenosis. Using SPM and SPAM analyses, we compared the number of significant voxels and cerebral counts in basal and acetazolamide SPECT images before and after stenting, and assessed the perfusion changes and cerebral vascular reserve index (CVRI). The numbers of hypoperfusion voxels in SPECT images were decreased from 10,083 ± 8,326 to 4,531 ± 5,091 in basal images (P 0.0317) and from 13,398 ± 14,222 to 7,699 ± 10,199 in acetazolamide images (P = 0.0142) after MCA stenting. On SPAM analysis, the increases in cerebral counts were significant in acetazolamide images (90.9 ± 2.2 to 93.5 ± 2.3, P = 0.0098) but not in basal images (91 ± 2.7 to 92 ± 2.6, P = 0.1602). The CVRI also showed a statistically significant increase from before stenting (median 0.32; 95% CI -2.19-2.37) to after stenting (median 1.59; 95% CI -0.85-4.16; P = 0.0068). This study revealed the usefulness of voxel-based analysis of basal/acetazolamide brain perfusion SPECT after MCA stent placement. This study showed that SPM and SPAM analyses of basal/acetazolamide Tc-99m brain SPECT could be used to evaluate the short-term hemodynamic efficacy of successful MCA stent placement. (orig.)

  4. Caracterización de la restenosis de stents coronarios convencionales y liberadores de medicamentos en pacientes incluidos en el registro DRug Eluting STent (DREST Characterization of conventional coronary stents restenosis and drug eluting stents in patients included in the Drug Eluting Stent Registry (DREST

    Directory of Open Access Journals (Sweden)

    Jorge A Arroyave C

    2012-06-01

    risk factor associated with stent restenosis of drug-eluting stents (p <0.002. We found smaller diameter of the vessel involved as well as smaller diameter of the implanted stent mainly in the drug-eluting stents associated with stent restenosis (p = 0.000. The focal pattern of stent restenosis was higher with drug eluting stents, while the diffuse pattern with standard stents (p = 0.000. The one-year survival was higher in patients with drug-eluting stent. Conclusions: The rates of stent restenosis and the related characteristics found are similar to those currently published. Dyslipidemia appears as a significant associated factor. The stent restenosis manifested as acute coronary syndrome in 60% of cases; it can not be regarded as a benign condition in this population.

  5. Optical Coherence Tomography Guided Percutaneous Coronary Intervention With Nobori Stent Implantation in Patients With Non-ST-Segment-Elevation Myocardial Infarction (OCTACS) Trial

    DEFF Research Database (Denmark)

    Antonsen, Lisbeth; Thayssen, Per; Maehara, Akiko

    2015-01-01

    (s). A final OCT was performed in case of reintervention. Six-month OCT follow-up was available in 85 patients. Twenty-three (46%) OCT-guided patients had additional postdilation or stenting. The percentage of acutely malapposed struts was substantially lower in the OCT-guided group (3.4% [interquartile range......, 0.3-7.6] versus 7.8% [interquartile range, 2.3-19.4]; Pinterquartile range, 1.2-9.8] versus 9.0% [interquartile range, 5.5-14.5], P

  6. Assessment of the Survival of Dental Implants in Irradiated Jaws ...

    African Journals Online (AJOL)

    producing xerostomia, mucositis, and altering the healing process in irradiated tissues. Dental implants avoid these ... to radiotherapy for treatment of cancer have reduced healing capacity due to progressive fibrosis of ..... in irradiated and non-irradiated minipig alveolar bone: An experimental study. Clin Oral Implants Res ...

  7. Assessment of the survival of dental implants in irradiated jaws ...

    African Journals Online (AJOL)

    Background: In patients undergoing head and neck surgery for various pathologic conditions, implants are one of the best restorative options and are increasing widely used. Therefore, we evaluated the success of dental implants in the irradiated jaws of patients following treatment of oral cancer oral cancer treated patients ...

  8. Osseointegration of a Zirconia Implant : A Histologic Assessment

    NARCIS (Netherlands)

    Schepke, Ulf; Meijer, Gert J; Meijer, Henny Ja; Walboomers, X Frank; Cune, Marco

    2017-01-01

    PURPOSE: The aim of this study was to describe the histologic and histomorphometric features of a retrieved, functional endosseous zirconia implant in a human subject. MATERIALS AND METHODS: A maxillary zirconia implant (ZV3) placed in a 52-year-old man was retrieved after 2 years of uncompromised

  9. An experimental examination of mutimodal imagine system for implant site assessment

    International Nuclear Information System (INIS)

    Park, Chang Seo; Kim, Kee Deog

    1998-01-01

    The scanora X-ray unit uses the principles of narrow beam radiography and spiral tomography. Starting with a panoramic overview as a scout image, multiple tomographic projection could be selected. This study evaluated the accuracy of spiral tomography in comparison to routine panoramic radiography for dental implant treatment planing. An experimental study was performed on a cadaver mandible to assess the accuracy of panoramic radiography and spiral tomography film images for measurement of metallic spheres. After radiographic images of the metallic spheres on the surgical stent were measured and corrected for a fixed magnification of radiographic images, following results were obtained. 1. In the optimal position of the mandible, the minimal horizontal and vertical distortion was evident in the panoramic radiography images. The mean horizontal and vertical magnification error in anterior sites was 5.25% and 0.75%, respectively. The mean horizontal and vertical magnification error in posterior sites was 0.50% and 1.50%, respectively. 2. In the displaced forward or in and eccentric position of the mandible, the magnification error of the panoramic radiography images increased significantly over the optimal position. Overall, the mean horizontal magnification error of the anterior site in the different position changed dramatically within a range of -17.25% to 39.00%, compared to the posterior range of -5.25% to 8.50%. However, the mean vertical magnification error stayed with the range of 0.5% to 3.75% for all the mandibular positions. 3. The magnification effects in the tomographic scans were nearly identical for the anterior and posterior with a range of 2.00% to 5.75% in the horizontal and 4.50% to 5.50% in the vertical dimension, respectively. 4. A statistically significant difference between the anterior and posterior measurements was found in the horizontal measurements of the panoramic radiography images of the displaced dorward and backward position of the

  10. An experimental examination of mutimodal imagine system for implant site assessment

    Energy Technology Data Exchange (ETDEWEB)

    Park, Chang Seo; Kim, Kee Deog [Dept. of Dental Radiology, College of Dentistry, Yonsei University, Seoul (Korea, Republic of)

    1998-02-15

    The scanora X-ray unit uses the principles of narrow beam radiography and spiral tomography. Starting with a panoramic overview as a scout image, multiple tomographic projection could be selected. This study evaluated the accuracy of spiral tomography in comparison to routine panoramic radiography for dental implant treatment planing. An experimental study was performed on a cadaver mandible to assess the accuracy of panoramic radiography and spiral tomography film images for measurement of metallic spheres. After radiographic images of the metallic spheres on the surgical stent were measured and corrected for a fixed magnification of radiographic images, following results were obtained. 1. In the optimal position of the mandible, the minimal horizontal and vertical distortion was evident in the panoramic radiography images. The mean horizontal and vertical magnification error in anterior sites was 5.25% and 0.75%, respectively. The mean horizontal and vertical magnification error in posterior sites was 0.50% and 1.50%, respectively. 2. In the displaced forward or in and eccentric position of the mandible, the magnification error of the panoramic radiography images increased significantly over the optimal position. Overall, the mean horizontal magnification error of the anterior site in the different position changed dramatically within a range of -17.25% to 39.00%, compared to the posterior range of -5.25% to 8.50%. However, the mean vertical magnification error stayed with the range of 0.5% to 3.75% for all the mandibular positions. 3. The magnification effects in the tomographic scans were nearly identical for the anterior and posterior with a range of 2.00% to 5.75% in the horizontal and 4.50% to 5.50% in the vertical dimension, respectively. 4. A statistically significant difference between the anterior and posterior measurements was found in the horizontal measurements of the panoramic radiography images of the displaced dorward and backward position of the

  11. Teaching and assessment of implant dentistry in undergraduate and postgraduate education: a European consensus.

    Science.gov (United States)

    Mattheos, N; Albrektsson, T; Buser, D; De Bruyn, H; Donos, N; Hjørting Hansen, E; Lang, N P; Sanz, M; Nattestad, A

    2009-02-01

    This paper constitutes a summary of the consensus documents agreed at the First European Workshop on Implant Dentistry University Education held in Prague on 19-22 June 2008. Implant dentistry is becoming increasingly important treatment alternative for the restoration of missing teeth, as patients expectations and demands increase. Furthermore, implant related complications such as peri-implantitis are presenting more frequently in the dental surgery. This consensus paper recommends that implant dentistry should be an integral part of the undergraduate curriculum. Whilst few schools will achieve student competence in the surgical placement of implants this should not preclude the inclusion of the fundamental principles of implant dentistry in the undergraduate curriculum such as the evidence base for their use, indications and contraindications and treatment of the complications that may arise. The consensus paper sets out the rationale for the introduction of implant dentistry in the dental curriculum and the knowledge base for an undergraduate programme in the subject. It lists the competencies that might be sought without expectations of surgical placement of implants at this stage and the assessment methods that might be employed. The paper also addresses the competencies and educational pathways for postgraduate education in implant dentistry.

  12. Biodegradable Metals for Cardiovascular Stent Application: Interests and New Opportunities

    Directory of Open Access Journals (Sweden)

    Maryam Moravej

    2011-06-01

    Full Text Available During the last decade, biodegradable metallic stents have been developed and investigated as alternatives for the currently-used permanent cardiovascular stents. Degradable metallic materials could potentially replace corrosion-resistant metals currently used for stent application as it has been shown that the role of stenting is temporary and limited to a period of 6–12 months after implantation during which arterial remodeling and healing occur. Although corrosion is generally considered as a failure in metallurgy, the corrodibility of certain metals can be an advantage for their application as degradable implants. The candidate materials for such application should have mechanical properties ideally close to those of 316L stainless steel which is the gold standard material for stent application in order to provide mechanical support to diseased arteries. Non-toxicity of the metal itself and its degradation products is another requirement as the material is absorbed by blood and cells. Based on the mentioned requirements, iron-based and magnesium-based alloys have been the investigated candidates for biodegradable stents. This article reviews the recent developments in the design and evaluation of metallic materials for biodegradable stents. It also introduces the new metallurgical processes which could be applied for the production of metallic biodegradable stents and their effect on the properties of the produced metals.

  13. Advantages and disadvantages of biodegradable platforms in drug eluting stents.

    Science.gov (United States)

    Rodriguez-Granillo, Agustina; Rubilar, Bibiana; Rodriguez-Granillo, Gaston; Rodriguez, Alfredo E

    2011-03-26

    Coronary angioplasty with drug-eluting stent (DES) implantation is currently the most common stent procedure worldwide. Since the introduction of DES, coronary restenosis as well as the incidence of target vessel and target lesion revascularization have been significantly reduced. However, the incidence of very late stent thrombosis beyond the first year after stent deployment has more commonly been linked to DES than to bare-metal stent (BMS) implantation. Several factors have been associated with very late stent thrombosis after DES implantation, such as delayed healing, inflammation, stent mal-apposition and endothelial dysfunction. Some of these adverse events were associated with the presence of durable polymers, which were essential to allow the elution of the immunosuppressive drug in the first DES designs. The introduction of erodable polymers in DES technology has provided the potential to complete the degradation of the polymer simultaneously or immediately after the release of the immunosuppressive drug, after which a BMS remains in place. Several DES designs with biodegradable (BIO) polymers have been introduced in preclinical and clinical studies, including randomized trials. In this review, we analyze the clinical results from 6 observational and randomized studies with BIO polymers and discuss advantages and disadvantages of this new technology.

  14. Electronic assessment of peri-implant mucosal esthetics around three implant-abutment configurations: a randomized clinical trial.

    Science.gov (United States)

    Barwacz, Christopher A; Stanford, Clark M; Diehl, Ursula A; Qian, Fang; Cooper, Lyndon F; Feine, Jocelyne; McGuire, Michael

    2016-06-01

    To objectively assess the influence that three different implant-abutment interface designs had on peri-implant mucosal esthetics at 1 year post-implant placement via the pink esthetic score (PES). Additionally, to demonstrate the novel employment of a tablet-based digital imaging format to reliably assess and score clinical images as part of a multicenter clinical trial according to PES criteria. Adult subjects (n = 141) with healed tooth-bound edentulous sites in the anterior maxilla as well as first premolar region were randomized to receive one of three different implant-abutment interface designs (conical interface = CI; flat-to-flat interface = FI; or platform switch interface = PS). Immediate provisionalization was performed with prefabricated titanium abutments, with definitive custom CAD/CAM zirconia abutments and all-ceramic cement-based crowns being delivered 12-week post-implant placement. Bilateral (anterior sites) or unilateral (premolar sites) digital clinical photographs were made at 1, 3, 6, and 12 months post-implant placement. Five calibrated faculty evaluators of different clinical backgrounds scored images during a 4-week timeframe on a standardized, tablet-based, digital imaging format. Six hundred and forty-nine clinical photographs were evaluated resulting in a total of 3245 sum PES values and 22,715 individual PES values. Faculty evaluator intra- and inter-rater reliability was found to be "strong" (ICC = 0.84) and "substantial" (ICC = 0.64), respectively, demonstrating repeatability of both the PES, evaluator calibration, and standardization of tablet-based scoring. All implant-abutment interface groups demonstrated significant improvements in mean sum PESs up to 1 year, with the largest improvement between restoration delivery and 6 months. No significant differences were found between groups in mean sum PESs both for individual study visits as well as for changes between study visits. No significant differences in mean

  15. Assessment of modified gold surfaced titanium implants on skeletal fixation

    DEFF Research Database (Denmark)

    Zainali, Kasra; Danscher, Gorm; Jakobsen, Thomas

    2013-01-01

    shown to liberate gold ions through the process termed dissolucytosis. Furthermore, gold ions are known to act in an anti-inflammatory manner by inhibiting cellular NF-κB-DNA binding. The present study investigated whether partial coating of titanium implants could augment early osseointegration...... osseointegration compared to control titanium implants in a similar model. Since sufficient early mechanical fixation is achieved with this new coating, it is reasonable to investigate the implant further in long-term studies. © 2012 Wiley Periodicals, Inc....

  16. Assessment of the implant geometry in fractionated interstitial HDR breast brachytherapy using an electromagnetic tracking system.

    Science.gov (United States)

    Kellermeier, Markus; Fietkau, Rainer; Strnad, Vratislav; Bert, Christoph

    During the partial-breast treatment course by interstitial brachytherapy, electromagnetic tracking (EMT) was applied to measure the implant geometry. Implant-geometry variation, choice of reference data, and three registration methods were assessed. The implant geometry was measured in 28 patients after catheter implantation (EMT bed ), during CT imaging (EMT CT ), and in each of up to n = 9 treatment fractions (EMT F(k), k = 1, 2,… n ). EMT F(k) were registered to the planned implant reconstruction (CT plan ) by using all dwell positions (DPs), the button centers, or three fiducial sensors on the patient's skin. Variation in implant geometry obtained from EMT F(k) was assessed for EMT bed, EMT CT , and CT plan . EMT was used to measure 3932 catheters. A duration of 6.5 ± 1.7 min was needed for each implant measurement (mean, 17 catheters) plus setup of the EMT system. Data registration based on the DP deviated significantly lower than registration on button centers or fiducial sensors. Within a registration group, there was a geometry in high-dose-rate interstitial brachytherapy breast treatments. EMT bed , EMT CT , and CT plan data can serve as reference for assessment of implant changes. Copyright © 2017 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  17. Sirolimus-eluting stents for the treatment of symptomatic extracranial vertebral artery stenoses: Early experience and 6-month follow-up; Die Behandlung symptomatischer extrakranieller Stenosen der Arteria vertebralis mit sirolimusbeschichteten Stents: erste Erfahrungen und Ergebnisse nach 6 Monaten

    Energy Technology Data Exchange (ETDEWEB)

    Lugmayr, H.; Kastner, M.; Froehler, W.; Meindl, S.; Zisch, R. [Krankenhaus Wels (Austria). Institut fuer Radiologie

    2004-10-01

    Purpose: To evaluate the clinical and morphological effectiveness of sirolimus-eluting stents in patients with stenoses in the extracranial vertebral artery and to assess the 6-month results. Materials and Methods: Sirolimus-eluting stents were implanted in 8 stenoses of the extracranial vertebral artery in 7 patients with symptoms of vertebrobasilar insufficiency. Seven stenoses were located at the ostium, and one further cranially in segment V 1. The mean grade diameter of the stenoses was 85.1% (60.9%-98.3%). Clinical and angiographic follow-up was performed over a period of 6 months in all patients. Results: All lesions were successfully stented with a residual stenosis of 20.2% (0.0-38.5%). Clinically, all patients showed resolution or improvement of the symptoms after stenting. After 6 months, 5 of the 8 stenoses developed intimal hyperplasia with a stenosis grade >50%. The mean measured grade of stenosis after 6 months was 56.2% (0.0-94.1%). Five patients had no clinical symptoms of a vertebrobasilar insufficiency while two had recurrent symptoms. Conclusion: Sirolimus-eluting stents in the extracranial vertebral artery have a high and unsatisfactory re-stenosis rate after 6 months. (orig.)

  18. Accuracy of multislice CT angiography for the assessment of in-stent restenoses in the iliac arteries at reduced dose: a phantom study.

    Science.gov (United States)

    Perisinakis, K; Manousaki, E; Zourari, K; Tsetis, D; Tzedakis, A; Papadakis, A; Karantanas, A; Damilakis, J

    2011-03-01

    We investigated the potential of low-dose CT angiography for accurate assessment of in-stent restenoses (ISRs) of the iliac artery. A Rando anthropomorphic phantom (Alderson Research Labs, Stanford, CA), custom-made wax simulating hyperplastic tissue and a nitinol stent were used to simulate a patient with clinically relevant iliac artery ISRs. The cylindrical lumen was filled with a solution of iodine contrast medium diluted in saline, representing a patient's blood during CT angiography. The phantom was subjected to standard- and low-dose angiographic exposures using a modern multidetector (MD) CT scanner. The percentage of ISR was determined using the profile along a line normal to the lumen axis on reconstructed images of 2 and 5 mm slice thickness. Percentage ISRs derived using the standard- and low-dose protocols were compared. In a preliminary study, seven patients with stents were subjected to standard- and low-dose MDCT angiography during follow-up. The resulting images were assessed and compared by two experienced radiologists. The accuracy in measuring the percentage ISR was found to be better than 12% for all simulated stenoses. The differences between percentage ISRs measured on images obtained at 120 kVp/160 mAs and 80 kVp/80 mAs were below 6%. Patient image sets acquired using low-exposure factors were judged to be of satisfactory diagnostic quality. The assessment of ISR did not differ significantly between image sets acquired using the standard factors and those acquired using the low-exposure factors, although the mean reduction in patient effective dose was 48%. A reduction in exposure factors during MDCT angiography of the iliac artery is possible without affecting the accuracy in the determination of ISRs.

  19. Combined use of transcranial magnetic stimulation and metal electrode implants: a theoretical assessment of safety considerations

    Science.gov (United States)

    Golestanirad, Laleh; Rouhani, Hossein; Elahi, Behzad; Shahim, Kamal; Chen, Robert; Mosig, Juan R.; Pollo, Claudio; Graham, Simon J.

    2012-12-01

    This paper provides a theoretical assessment of the safety considerations encountered in the simultaneous use of transcranial magnetic stimulation (TMS) and neurological interventions involving implanted metallic electrodes, such as electrocorticography. Metal implants are subject to magnetic forces due to fast alternating magnetic fields produced by the TMS coil. The question of whether the mechanical movement of the implants leads to irreversible damage of brain tissue is addressed by an electromagnetic simulation which quantifies the magnitude of imposed magnetic forces. The assessment is followed by a careful mechanical analysis determining the maximum tolerable force which does not cause irreversible tissue damage. Results of this investigation provide useful information on the range of TMS stimulator output powers which can be safely used in patients having metallic implants. It is shown that conventional TMS applications can be considered safe when applied on patients with typical electrode implants as the induced stress in the brain tissue remains well below the limit of tissue damage.

  20. Drug-eluting or bare-metal stents for large coronary vessel stenting? The BASKET-PROVE (PROspective Validation Examination) trial: Study protocol and design

    DEFF Research Database (Denmark)

    Pfisterer, M.; Bertel, O.; Bonetti, P.O.

    2008-01-01

    Background Based on a subgroup analysis of 18-month BAsel Stent Kosten Effektivitats Trial (BASKET) outcome data, we hypothesized that very late (>12 months) stent thrombosis occurs predominantly after drug-eluting stent implantation in large native coronary vessel stenting. Methods To prove...... or refute this hypothesis, we set up an 11-center 4-country prospective trial of 2260 consecutive patients treated with >= 3.0-mm stents only, randomized to receive Cypher (Johnson & Johnson, Miami Lakes, FL), Vision (Abbott Vascular, Abbott Laboratories, IL), or Xience stents (Abbott Vascular). Only...... to cobalt-chromium bare-metal stents in this relevant, low-risk group of everyday patients. In addition, a comparison with similar BASKET patients will allow to estimate the impact of 12-versus 6-month dual antiplatelet therapy on these outcomes Udgivelsesdato: 2008/4...

  1. Random spectrum loading of dental implants: An alternative approach to functional performance assessment.

    Science.gov (United States)

    Shemtov-Yona, K; Rittel, D

    2016-09-01

    The fatigue performance of dental implants is usually assessed on the basis of cyclic S/N curves. This neither provides information on the anticipated service performance of the implant, nor does it allow for detailed comparisons between implants unless a thorough statistical analysis is performed, of the kind not currently required by certification standards. The notion of endurance limit is deemed to be of limited applicability, given unavoidable stress concentrations and random load excursions, that all characterize dental implants and their service conditions. We propose a completely different approach, based on random spectrum loading, as long used in aeronautical design. The implant is randomly loaded by a sequence of loads encompassing all load levels it would endure during its service life. This approach provides a quantitative and comparable estimate of its performance in terms of lifetime, based on the very fact that the implant will fracture sooner or later, instead of defining a fatigue endurance limit of limited practical application. Five commercial monolithic Ti-6Al-4V implants were tested under cyclic, and another 5 under spectrum loading conditions, at room temperature and dry air. The failure modes and fracture planes were identical for all implants. The approach is discussed, including its potential applications, for systematic, straightforward and reliable comparisons of various implant designs and environments, without the need for cumbersome statistical analyses. It is believed that spectrum loading can be considered for the generation of new standardization procedures and design applications. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. 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

    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...

  3. Allergy to Surgical Implants.

    Science.gov (United States)

    Pacheco, Karin A

    2015-01-01

    Surgical implants have a wide array of therapeutic uses, most commonly in joint replacements, but also in repair of pes excavatum and spinal disorders, in cardiac devices (stents, patches, pacers, valves), in gynecological implants, and in dentistry. Many of the metals used are immunologically active, as are the methacrylates and epoxies used in conjunction with several of these devices. Allergic responses to surgical components can present atypically as failure of the device, with nonspecific symptoms of localized pain, swelling, warmth, loosening, instability, itching, or burning; localized rash is infrequent. Identification of the specific metal and cement components used in a particular implant can be difficult, but is crucial to guide testing and interpretation of results. Nickel, cobalt, and chromium remain the most common metals implicated in implant failure due to metal sensitization; methacrylate-based cements are also important contributors. This review will provide a guide on how to assess and interpret the clinical history, identify the components used in surgery, test for sensitization, and provide advice on possible solutions. Data on the pathways of metal-induced immune stimulation are included. In this setting, the allergist, the dermatologist, or both have the potential to significantly improve surgical outcomes and patient care. Copyright © 2015 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  4. Stenting in paediatric and adult congenital heart diseases: A French multicentre study in the current era.

    Science.gov (United States)

    Hascoët, Sebastien; Jalal, Zakaria; Baruteau, Alban; Mauri, Lucia; Chalard, Aurélie; Bouzguenda, Ivan; Piéchaud, Jean-François; Thambo, Jean-Benoit; Lefort, Bruno; Guérin, Patrice; Le Gloan, Lauriane; Acar, Philippe; Houeijeh, Ali; Godart, François; Fraisse, Alain

    2015-12-01

    Many stents are used "off-label" during the management of congenital heart diseases (CHD). To describe indications for, results of, and adverse events associated with stenting in CHD in current practice. Participation in this study was proposed to all catheterization laboratories that specialize in CHD in France (M3C network). All paediatric and adult CHD cases with stent implantation in 2013 were included retrospectively. Overall, 207 stents were implanted in 151 patients across 11 centres. Median age was 13.7 years (range, 5 days to 70.1 years). Main procedure indications were branch pulmonary artery angioplasty (n=46, 29.1%), aortic (re)coarctation stenting (n=43, 27.2%), percutaneous pulmonary valve implantation (n=32, 20.2%) and ductus arteriosus stenting (n=14, 8.9%). The main stents implanted were the CP Stent™ (n=61, 29.5%), the Max™ LD stent (n=43, 20.8%), the Valeo(®) stent (n=28, 13.5%) and valved stents (n=30, 14.5%). Procedures were considered successful in 96.8% of cases (95% confidence interval [CI] 92.8-99.0%). Adverse events were observed in 23 procedures (14.7%, 95% CI 9.5-21.0%). Ductus arteriosus stenting (odds ratio 12.4, 95% CI 2.0-77.5; P<0.01) and pulmonary revalvulation (odds ratio 5.9, 95% CI 1.1-32.3; P=0.04) were risk markers for stent-related adverse events. Stents are used in various CHD catheterization procedures, from infancy to adult age. The adverse events rate is significant and is related to the type of procedure. Copyright © 2015. Published by Elsevier Masson SAS.

  5. 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.

  6. Outcome Assessment after Aptis Distal Radioulnar Joint (DRUJ Implant Arthroplasty

    Directory of Open Access Journals (Sweden)

    Amir Reza Kachooei

    2014-09-01

    Full Text Available Background:  Conventional treatments after complicated injuries of the distal radioulnar joint (DRUJ such as Darrach and Kapandji-Sauvé procedures have many drawbacks, which may eventually lead to a painful unstable distal ulna.  The development of DRUJ prosthesis has significantly evolved over the past years. In this study, we assessed the outcome results of patients after DRUJ implant arthroplasty using the Aptis (Scheker prosthesis. Methods: We identified 13 patients with 14 prosthesis during the past 10 years. Patients underwent DRUJ arthroplasty due to persistent symptoms of instability, chronic pain, and stiffness. Records and follow-up visits were reviewed to find the final post-operative symptoms, pain, range of motion, and grip strength with a mean follow-up of 12 months (range: 2-25 months. Also, patients were contacted prospectively by phone in order to  minister the disabilities of the armshoulder and hand (DASH, patient rated wrist evaluation (PRWE, and visual analogue scale (VAS, and to interview regarding satisfaction and progress in daily activities. Eleven patients out of 13 could be reached with a median followup time of 60 months (range: 2 to 102 months.  Results: No patient required removal of the prosthesis. Only two patients underwent secondary surgeries in which both required debridement of the screw tip over the radius. The median DASH score, PRWE score, VAS, and satisfaction were 1.3, 2.5, 0, and 10, respectively. The mean range of flexion, extension, supination, and pronation was 62, 54, 51, and 64, respectively. Conclusions: Distal radioulnar joint injuries are disabling and patients usually undergo one or more salvage surgeries prior to receiving an arthroplasty. The Scheker prosthesis has shown satisfactory results with 100% survival rate in all reports. The constrained design of this prosthesis gives enough stability to prevent painful subluxation.

  7. Changes in resonance frequency analysis assessed by Osstell mentor during osseointegration: comparison between immediately loaded implants and control implants without load

    Directory of Open Access Journals (Sweden)

    M. González-Jaranay

    2014-10-01

    Full Text Available Aim: The aim of this prospective clinical study was to evaluate the changes in resonance frequency analysis (RFA, assessed by Osstell Mentor, obtaining information on the implant stability quotient (ISQ during implants tissue integration for immediately loaded and non-loaded control implants. Materials and methods: A total of 40 implants, 20 implants with no immediate loading (control and 20 immediately loaded implants (test, were placed in 15 patients. ISQ implants was evaluated at baseline and at 6 and 8 weeks. Provisional crowns were removed at 8 weeks, when the definitive restoration was placed. Data of control and test implants and maxillary and mandibular areas were statistically compared. Results: At 8 weeks, all implants were integrated and there were no major postoperative complications. A statistically significant difference was found only at baseline between test and control maxillary implants (p=0.009 but not at 6 or 8 weeks (p>0.05. Conclusion: Immediate loading procedures may be applied with primary stability ISQ values >60 and inserted with a force of ≥30 N. The Osstell Mentor RFA may offer an objective method to determine when implant stability is adequate for immediate loading.

  8. Relation of body mass index to risk of stent thrombosis after percutaneous coronary intervention

    DEFF Research Database (Denmark)

    Schmiegelow, Michelle; Torp-Pedersen, Christian; Gislason, Gunnar H

    2012-01-01

    (BMS or DES) implanted at the index PCI were included. Median follow-up period was 26 months (interquartile range 12 to 44) and definite stent thrombosis occurred in 78 patients. Hazard ratio of definite stent thrombosis adjusted for number of stents at the index PCI was 0.92 (95% confidence interval...... [CI] 0.86 to 0.97) for each increase in kilograms per square meter of BMI. There was no significant interaction between stent type and BMI (p = 0.48). Hazard ratios for probable stent thrombosis and possible stent thrombosis adjusted for numbers of stents at the index PCI were 1.01 (CI 0.99 to 1...... mass index (BMI) and stent thrombosis after PCI with bare-metal stent (BMS) or drug-eluting stent (DES). We followed 5,515 patients who underwent PCI with implantation of ≥1 BMS or DES at a high-volume tertiary invasive cardiology center from 2000 through 2006. Only patients with a single type of stent...

  9. A novel device for resonance frequency assessment of one-piece implants.

    Science.gov (United States)

    Gabay, Eran; Cohen, Omer; Machtei, Eli E

    2012-01-01

    Immediate loading and/or restoration of dental implants requires the assessment of implant stability, which is best performed by resonance frequency analysis (RFA) prior to loading. One-piece dental implants are usually used for immediate loading, but there is currently no available reliable method to assess the primary stability of one-piece dental implants. Therefore, this study sought to validate a novel device designed for RFA measurements of one-piece implants. Thirty (3.75 x 13 mm) internal-hex implants (Seven, MIS) were divided into two groups; 15 were placed in an acrylic glass block and 15 were placed in fresh porcine jawbone using 30 N/cm2 of insertion torque. Implant stability quotient (ISQ) values were measured using the Osstell Mentor device; then, a new external fixation device was attached to the implant abutment with a 10-mm arm extending from the implant to an internal-hex ring at its proximal end. ISQ values were measured at the implant's internal hex and at the internal hex of the device, and the damping ratio was calculated. The measurements were repeated with 15 (3 x 13 mm) one-piece implants (UNO, MIS) attached to the same device. The damping ratio between the implant and the proximal device was 23.6% ± 4% in acrylic glass (50.1 ± 1.7 ISQ and 38.2 ± 1.8 ISQ, respectively) and 23.1% ± 3% in porcine bone (74.9 ± 2.8 ISQ and 57.5 ± 0.5 ISQ, respectively). ISQ values determined by the device on one-piece and two-piece implants were similar (57.4 ± 0.9 and 57.5 ± 0.5, respectively). With the present validation of this external fixation device for the measurements of implant stability using RFA, it is now possible to measure primary stability of any one-piece implant system, obviating the need for custom-made Osstell adaptors.

  10. Diagnostic accuracy of coronary in-stent restenosis using 320-row multidetector computed tomography

    International Nuclear Information System (INIS)

    Koeda, Tatsuhiko; Fusazaki, Tetsuya; Niinuma, Hiroyuki; Itoh, Tomonori; Tanaka, Ryoichi; Yoshioka, Kunihiro; Nakamura, Motoyuki

    2010-01-01

    Although a multidetector computed tomography (MDCT) was useful in assessing coronary artery disease, there were several limitations in detecting coronary in-stent restenosis (ISR). The aim of this study was to evaluate the diagnostic accuracy of coronary ISR using a 320-row MDCT (area detector computed tomography: ADCT) in patients after stent implantation. We performed ADCT in consecutive 102 patients (133 lesions) before coronary arteriography (CAG). In 133 lesions, 74 were treated with bare metal stents and 59 with drug eluting stents. The diagnostic accuracy of ADCT for coronary ISR was compared to the results of CAG. ISR was found in 18 cases with CAG analysis. To compare with CAG, sensitivity, specificity, positive predictive value, and negative predictive value to evaluate ISR by ADCT were 100%, 87.8%, 56.3% and 100% respectively. The ISR in a wide range of coronary artery disease was detected by ADCT with good diagnostic accuracy. ADCT may be a promising noninvasive diagnostic imaging modality to evaluate coronary ISR. (author)

  11. Initial clinical experience with the trabecular micro-bypass stent in patients with glaucoma.

    Science.gov (United States)

    Spiegel, Detlev; Wetzel, Wolfgang; Haffner, David S; Hill, Richard A

    2007-01-01

    This study was undertaken to evaluate the efficiency of a trabecular micro-bypass stent designed to allow direct aqueous drainage from the anterior chamber into Schlemm's canal in patients with glaucoma. In this prospective case series of 6 patients with open-angle glaucoma, the microstent was inserted ab interno under local anesthesia in an ophthalmic operating room. Patients were seen postoperatively at 1 to 2 d, 1 wk, and 1, 2, 6, and 12 mo. All stents were successfully placed within Schlemm's canal. Mean intraocular pressure (IOP) at preoperative baseline was 20.2+/-6.3 mm Hg (range, 14-31 mm Hg). Mean IOP decreased during the immediate postoperative period to approximately 12 to 13 mm Hg and was stabilized at 14 to 15 mm Hg with reduction of medication throughout 1 y of follow-up. No major complications occurred. According to observations reported in this feasibility study, the microstent was effective in reducing IOP and in decreasing the number of glaucoma medications required to control IOP. Implantation procedures were safe, and stents remained in place throughout the follow-up period. None of the complications traditionally associated with filtering surgery were reported. Further research on this stent in a larger group of patients is needed to assess its role in glaucoma therapy.

  12. [Biodegradable ureteral stents in treating patients with infravesical obstruction].

    Science.gov (United States)

    Chepurov, A K; Krivoborodov, G G; Zubarev, A V; Zaĭtsev, N V; Markina, N Iu

    2003-01-01

    Biodegradable endoprostheses SR-PLGA and SR-PLLA were used in combined treatment of 39 patients with urethral stricture (n = 24), neurogenic urinary bladder (n = 9), benign prostatic hyperplasia (n = 4), prostatic cancer (n = 2). In definition of indications for stent implantation the leading role was assigned to preoperative diagnosis of the state of the urinary bladder, urethra and sphincters using urodynamic tests and dynamic Doppler and three-dimensional echourethrography. Introduction of biodegradable urethral stents provides adequate spontaneous urination and allows avoiding external drainage. This prevents nosocomial infection and lowers the number of inflammatory complications. Palliative usage of stents in inoperable and neurological patients is effective in their medical and social rehabilitation. Analysis of errors and complications in 8 patients demonstrates that implantation of biodegradable stents is not absolute safe and requires some caution.

  13. Prospective versus retrospective ECG gating for dual source CT of the coronary stent: Comparison of image quality, accuracy, and radiation dose

    Energy Technology Data Exchange (ETDEWEB)

    Zhao Lei, E-mail: zhaolei219@sohu.com [Beijing Anzhen Hospital of the Capital University of Medical Sciences (China); Zhang Zhaoqi; Fan Zhanming; Yang Lin; Du Jing [Beijing Anzhen Hospital of the Capital University of Medical Sciences (China)

    2011-03-15

    Objective: To compare image quality, diagnostic accuracy and radiation dose of prospective and retrospective electrocardiogram (ECG) gated dual source computed tomography (DSCT) for the evaluation of the coronary stent, using conventional coronary angiography (CA) as a standard reference. Design, setting and patients: Sixty patients (heart rates {<=}70 bpm) with previous stent implantation who were scheduled for CA were divided in two groups, receiving either prospective or retrospective ECG gated DSCT separately. Two reviewers scored coronary stent image quality and evaluated stent lumen. Results: There was no significant difference in image quality between the two groups. In the prospective group, there were 86.4% (51/59) stents with interpretable images, in the retrospective group, there were 87.5% (49/56) stents with interpretable images. Image quality was not influenced by age, body mass index or heart rate in either group, but heart rate variability had a weak impact on the image quality of the prospective group. Image noise was higher in the prospective group, but this difference reached statistical significance only by using a smooth kernel reconstruction. Per-stent based sensitivity, specificity, and positive and negative predictive value were 100%, 84.1%, 68.2%, and 100%, respectively, in the prospective CT angiography group and 94.4%, 86.8%, 77.3%, and 97.1%, respectively, in the retrospective CT angiography group. There was a significant difference in the effective radiation dose between the two groups, mean effective dose in the prospective and retrospective group was 2.2 {+-} 0.5 mSv (1.5-3.2 mSv) and 14.6 {+-} 3.3 mSv (10.0-20.4 mSv) (p < .001) respectively. Conclusions: Compared with retrospective CT angiography, prospective CT angiography has a similar performance in assessing coronary stent patency, but a lower effective dose in selected patients with regular heart rates {<=}70 bpm.

  14. Phenomenological needs assessment of parents of children with cochlear implants.

    Science.gov (United States)

    Mostafavi, Firoozeh; Hazavehei, Seyed Mohammad Mahdi; Oryadi-Zanjani, Mohammad Majid; Rad, Gholamreza Sharifi; Rezaianzadeh, Abbas; Ravanyar, Leila

    2017-09-01

    The use of cochlear implants has been a remarkable success in reducing disabilities in those with impaired hearing, which have made a significant change in the patients' quality of life. Only by relying on cochlear implants, disabilities cannot be eliminated in the hearing impaired, and, alongside this intervention, rehabilitation practices such as through family and community support are necessary. To explain the needs of parents of children with cochlear implants to increase the quality of rehabilitation services and family-based interventions. A descriptive phenomenology study was performed with the participation of 16 people, including eight mothers, three fathers, and five experts involved with the rehabilitation of children aged 2-7 years with cochlear implants. The research setting was centers with speech therapy service providers for hearing-impaired children in the city of Shiraz (Iran) in 2015. Information was gathered through in-depth interviews with participants and analyzed by using Colaizzi's nine-step analysis method and MAXQDA (Ver10) applications. The mean age of participants was 34 years, and the average age of diagnosis of hearing problems in children was 12 months. The obtained data from the analysis of interviews about the needs of parents of children with cochlear implants were categorized into 19 sub-contents and five contents, as follows: the need for access to health care services; psychological needs; mood-related needs of a child; educational needs and financial requirements. Parents of children with cochlear implants have numerous needs, and they encounter problems based on their situation and experiences. The results indicate the necessity of close cooperation among different professionals such as an audiologist, pediatrician, psychologist, and speech therapist for the program's success.

  15. Treatment of malignant gastroduodenal obstruction with using a newly designed complex expandable nitinol stent: initial experiences

    International Nuclear Information System (INIS)

    Jung, Mi Hee; Ko, Ji Ho; Lee, Eun Jung; Oh, Kyeng Seung; Huh, Jin Do; Cho, Young Duk; Park, Seun Ja; Jung, Gyoo Sik

    2005-01-01

    We wanted to evaluate the usefulness of a new type of a complex expandable nitinol stent that was designed to reduce the stent's propensity to migration during the treatment of malignant gastroduodenal obstructions. Two types of expandable nitinol stent were constructed by weaving a single thread of 0.2mm nitinol wire in a tubular configuration: an uncovered stent 18mm in diameter and a covered stent 16mm in diameter. Both ends of the covered stent were fabricated by coaxially inserting the covered stent into the tubular uncovered stent and then attaching the two stents together with using nylon monofilament. Under fluoroscopic guidance, the stent was placed in 29 consecutive patients (20 men and 9 women, mean age: 65 years) who were suffering with malignant gastric outlet obstruction (n=20), duodenal obstruction (n=6) or combined obstruction (n=3). Clinical improvement was assessed by comparing the food intake capacity before and after the procedure. The complications were investigated during the follow up period. Stent placement was successful in all the patients. After stent placement, the symptoms improved in all but one patient. During the follow up, stent migration occurred in one patient (3%) at 34 days after the procedure. Despite the stent migration, the patient was able to resume a soft diet. Six patients developed recurrent symptoms of obstruction with tumor overgrowth at a mean of 145 days after the procedure; all the patients underwent coaxial placement of an additional stent with good results. One patient showed recurrence of obstruction due to tumor in-growth, and this was treated by placement of a second stent. Two patients with stent placement in the duodenum suffered from jaundice 26 days and 65 days, respectively, after their procedures. Placement of the newly designed complex expandable nitinol stent seems to be effective for the palliative treatment of malignant gastroduodenal obstructions. The new stent also seems to help overcome the

  16. Treatment of malignant gastroduodenal obstruction with using a newly designed complex expandable nitinol stent: initial experiences

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Mi Hee; Ko, Ji Ho; Lee, Eun Jung; Oh, Kyeng Seung; Huh, Jin Do; Cho, Young Duk; Park, Seun Ja [College of Medicine, Kosin University, Busan (Korea, Republic of); Jung, Gyoo Sik [Ulsan Hospital, Ulsan (Korea, Republic of)

    2005-12-15

    We wanted to evaluate the usefulness of a new type of a complex expandable nitinol stent that was designed to reduce the stent's propensity to migration during the treatment of malignant gastroduodenal obstructions. Two types of expandable nitinol stent were constructed by weaving a single thread of 0.2mm nitinol wire in a tubular configuration: an uncovered stent 18mm in diameter and a covered stent 16mm in diameter. Both ends of the covered stent were fabricated by coaxially inserting the covered stent into the tubular uncovered stent and then attaching the two stents together with using nylon monofilament. Under fluoroscopic guidance, the stent was placed in 29 consecutive patients (20 men and 9 women, mean age: 65 years) who were suffering with malignant gastric outlet obstruction (n=20), duodenal obstruction (n=6) or combined obstruction (n=3). Clinical improvement was assessed by comparing the food intake capacity before and after the procedure. The complications were investigated during the follow up period. Stent placement was successful in all the patients. After stent placement, the symptoms improved in all but one patient. During the follow up, stent migration occurred in one patient (3%) at 34 days after the procedure. Despite the stent migration, the patient was able to resume a soft diet. Six patients developed recurrent symptoms of obstruction with tumor overgrowth at a mean of 145 days after the procedure; all the patients underwent coaxial placement of an additional stent with good results. One patient showed recurrence of obstruction due to tumor in-growth, and this was treated by placement of a second stent. Two patients with stent placement in the duodenum suffered from jaundice 26 days and 65 days, respectively, after their procedures. Placement of the newly designed complex expandable nitinol stent seems to be effective for the palliative treatment of malignant gastroduodenal obstructions. The new stent also seems to help overcome the

  17. The Construct Validity and Reliability of an Assessment Tool for Competency in Cochlear Implant Surgery

    Directory of Open Access Journals (Sweden)

    Patorn Piromchai

    2014-01-01

    Full Text Available Introduction. We introduce a rating tool that objectively evaluates the skills of surgical trainees performing cochlear implant surgery. Methods. Seven residents and seven experts performed cochlear implant surgery sessions from mastoidectomy to cochleostomy on a standardized virtual reality temporal bone. A total of twenty-eight assessment videos were recorded and two consultant otolaryngologists evaluated the performance of each participant using these videos. Results. Interrater reliability was calculated using the intraclass correlation coefficient for both the global and checklist components of the assessment instrument. The overall agreement was high. The construct validity of this instrument was strongly supported by the significantly higher scores in the expert group for both components. Conclusion. Our results indicate that the proposed assessment tool for cochlear implant surgery is reliable, accurate, and easy to use. This instrument can thus be used to provide objective feedback on overall and task-specific competency in cochlear implantation.

  18. Desfechos clínicos por região geográfica em pacientes com implante de stent eluidor de Zotarolimus

    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 (<1,2% entre todos os pacientes em 1 ano e 2 anos. CONCLUSÃO: Os desfechos clínicos foram comparáveis entre os pacientes da América Latina e Europa, e América Latina e Pacífico Asiático, a despeito dos subgrupos clínicos menos favoráveis na América Latina, perfil de risco mais elevado e menor uso acentuado de terapia antiplaquetária dupla com o tempo.

  19. 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

  20. Outcomes of ≤6-month versus 12-month dual antiplatelet therapy after drug-eluting stent implantation: A meta-analysis and meta-regression.

    Science.gov (United States)

    Villablanca, Pedro A; Massera, Daniele; Mathew, Verghese; Bangalore, Sripal; Christia, Panagiota; Perez, Irving; Wan, Ningxin; Schulz-Schüpke, Stefanie; Briceno, David F; Bortnick, Anna E; Garcia, Mario J; Lucariello, Richard; Menegus, Mark; Pyo, Robert; Wiley, Jose; Ramakrishna, Harish

    2016-12-01

    The benefit of ≤6-month compared with 12-month dual antiplatelet therapy (DAPT) after percutaneous coronary intervention (PCI) with drug-eluting stent (DES) placement remains controversial. We performed a meta-analysis and meta-regression of ≤6-month versus 12-month DAPT in patients undergoing PCI with DES placement. We conducted electronic database searches of randomized controlled trials (RCTs) comparing DAPT durations after DES placement. For studies with longer follow-up, outcomes at 12 months were identified. Odds ratios and 95% confidence intervals were computed with the Mantel-Haenszel method. Fixed-effect models were used; if heterogeneity (I) > 40 was identified, effects were obtained with random models. Nine RCTs were included with total n = 19,224 patients. No significant differences were observed between ≤6-month compared with 12-month DAPT in all-cause mortality (OR 0.87; 95% confidence interval (CI): 0.69-1.11), cardiovascular (CV) mortality (OR 0.89; 95% CI: 0.66-1.21), non-CV mortality (OR 0.85; 95% 0.58-1.24), myocardial infarction (OR 1.10; 95% CI: 0.89-1.37), stroke (OR 0.97; 95% CI: 0.67-1.42), stent thrombosis (ST) (OR 1.37; 95% CI: 0.89-2.10), and target vessel revascularization (OR 0.95; 95% CI: 0.77-1.18). No significant difference in major bleeding (OR 0.72; 95% CI: 0.49-1.05) was observed, though the all-bleeding event rate was significantly lower in the ≤6-month DAPT group (OR 0.76; 95% CI: 0.59-0.96). In the meta-regression analysis, a significant association between bleeding events and non-CV mortality with 12-month DAPT was found, as well as between ST and mortality in addition to MI with ≤6-month DAPT. DAPT for ≤6 months is associated with similar mortality and ischemic outcomes but less bleeding events compared with 12-month DAPT after PCI with DES.

  1. A prospective clinical trial to assess the optical efficacy of pink neck implants and pink abutments on soft tissue esthetics.

    Science.gov (United States)

    Gil, Mindy S; Ishikawa-Nagai, Shigemi; Elani, Hawazin W; Da Silva, John D; Kim, David M; Tarnow, Dennis; Schulze-Späte, Ulrike; Bittner, Nurit

    2017-11-12

    The purpose of this prospective, randomized, controlled, multicenter clinical study was to analyze the optical effects of an anodized pink colored implant shoulder/abutment system in the peri-implant mucosa of immediately placed dental implants. Forty subjects with a restoratively hopeless tooth in the maxillary esthetic zone, were recruited and randomized to receive either a pink-neck implant, or a conventional gray implant. All patients received an immediate implant and immediate provisional and two identical CAD/CAM titanium abutments with different surface colors: pink and gray, and one zirconia all-ceramic crown. The color of the peri-implant mucosa was measured using a dental spectrophotometer and analyzed using CIELAB color system. The overall color difference between the peri-implant mucosa with a pink abutment and a gray abutment was ΔE = 4.22. Patients with gray implants presented a color change of ΔE = 3.86-4.17 with this abutment change, while patients with pink implants had a color change of ΔE = 3.84-4.69. The peri-implant mucosa with a pink abutment was significantly more red when compared with a gray abutment (P ≤ .01). When a pink abutment was used, there is a significant color change of the peri-implant mucosa that is above the detectable color threshold. Esthetic outcomes are important for the success of implant treatment of maxillary anterior implants. The phenomenon of the gray color of a dental implant and abutment shining through the peri-implant mucosa has been documented in the literature. The objective of this study was to assess the optical effect of an anodized pink-neck implant and a pink abutment on the color of peri-implant mucosa. This study demonstrates that using pink-neck implant and a pink abutment would contribute positively to the overall esthetic outcome for an anterior implant. © 2017 Wiley Periodicals, Inc.

  2. Many particle magnetic dipole-dipole and hydrodynamic interactions in magnetizable stent assisted magnetic drug targeting

    International Nuclear Information System (INIS)

    Cregg, P.J.; Murphy, Kieran; Mardinoglu, Adil; Prina-Mello, Adriele

    2010-01-01

    The implant assisted magnetic targeted drug delivery system of Aviles, Ebner and Ritter is considered both experimentally (in vitro) and theoretically. The results of a 2D mathematical model are compared with 3D experimental results for a magnetizable wire stent. In this experiment a ferromagnetic, coiled wire stent is implanted to aid collection of particles which consist of single domain magnetic nanoparticles (radius ∼10nm). In order to model the agglomeration of particles known to occur in this system, the magnetic dipole-dipole and hydrodynamic interactions for multiple particles are included. Simulations based on this mathematical model were performed using open source C++ code. Different initial positions are considered and the system performance is assessed in terms of collection efficiency. The results of this model show closer agreement with the measured in vitro experimental results and with the literature. The implications in nanotechnology and nanomedicine are based on the prediction of the particle efficiency, in conjunction with the magnetizable stent, for targeted drug delivery.

  3. 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)

  4. Preclinical evaluation of new indomethacin-eluting biodegradable urethral stent.

    Science.gov (United States)

    Kotsar, Andres; Nieminen, Riina; Isotalo, Taina; Mikkonen, Joonas; Uurto, Ilkka; Kellomäki, Minna; Talja, Martti; Moilanen, Eeva; Tammela, Teuvo L J

    2012-04-01

    To evaluate the effect of an indomethacin-eluting biodegradable urethral stent on the production of inflammatory cytokines in vitro and the degradation and biocompatibility of the new stent in vivo. The effects of an indomethacin and indomethacin-eluting biodegradable stent on monocyte chemoattractant protein (MCP)-1, RANTES (regulated on activation, normal T-cell expressed and secreted), and transforming growth factor-ß were measured in THP-1 cells by enzyme-linked immunosorbent assay. Stents (copolymer of L-lactide and glycolide acid) that were coated with 50L/50D polylactic acid and two different concentrations of indomethacin were inserted into the rabbit urethra. Stents without the drug were used as controls. Scanning electron microscopy (SEM) was used to assess the degradation of the stents. Biocompatibility was evaluated using histologic analyses of the urethral specimen. The measurements were performed at 3 weeks and 3 months. Indomethacin and indomethacin-releasing stent material inhibited MCP-1 and RANTES production in activated THP-1 macrophages. SEM analysis revealed that indomethacin coating had no effect on the degradation process of the stents and less epithelial polyposis had developed in the indomethacin stent group. In histologic analyses at 3 weeks, indomethacin-eluting stents caused more calcification but no significant differences in other tissue reactions. At 3 months, the indomethacin-eluting stents caused less inflammatory reaction and calcification compared with the control stents. Indomethacin-eluting property can be safely added to biodegradable stents without major influence on the degradation time. The development of epithelial polyposis in the urethra can be potentially reduced by the new indomethacin-eluting urethral stents.

  5. Ureteral in situ biocompatibility of L-lactide-glycolic acid copolymer 80:20 stent

    International Nuclear Information System (INIS)

    Hou Yuchuan; Wang Chunxi; Zhang Baogang; Chen Xuesi

    2006-01-01

    Objective: To evaluate the in situ biocompatibility of a new biodegradable ureteral stent made of L-lactide-glycolic acid copolymer 80:20 (PLGA 80:20). Methods: 16 dogs served as experimental animals. Ureteral stents of PLGA 80:20 were inserted in situ into the left ureter after transection at the mid level, then the ureters were routinely anastomosed. Ureters surrounding the stent were taken out 2, 4, 8 and 12 weeks postoperatively. The ureters were dissected to find changes of stents and local ureters. Histological analysis was performed to investigate tissue reactions to the stent and evaluate the biocompatibility. Rods of UROVISION stent served as controls. Results: The PLGA stent was degraded completely within 12 weeks post implantation. In the early stage (2-4 weeks), both stents induced epithelial hyperplasia and inflammatory cell reaction at local ureter (P>0.05). In the later stage (8-12 weeks), the tissue reaction nearly subsided in PLGA stented ureters after degradation of the device. Whereas, the tissue reaction induced by UROVISION stent had lasted throughout the observation period, even deteriorated with time going (P<0.05). Conclusion: The tissue reaction induced by PLGA stent is retrievable. PLGA is regarded highly compatible and can serve as an ideal material for biodegradable ureteral stent. (authors)

  6. Enteral stents.

    Science.gov (United States)

    Varadarajulu, Shyam; Banerjee, Subhas; Barth, Bradley; Desilets, David; Kaul, Vivek; Kethu, Sripathi; Pedrosa, Marcos; Pfau, Patrick; Tokar, Jeffrey; Wang, Amy; Song, Louis-Michel Wong Kee; Rodriguez, Sarah

    2011-09-01

    The American Society for Gastrointestinal Endoscopy (ASGE) Technology Committee provides reviews of existing, new, or emerging endoscopic technologies that have an impact on the practice of GI endoscopy. Evidence-based methodology is used, with a MEDLINE literature search to identify pertinent clinical studies on the topic and a MAUDE (U.S. Food and Drug Administration Center for Devices and Radiological Health) database search to identify the reported complications of a given technology. Both are supplemented by accessing the "related articles" feature of PubMed and by scrutinizing pertinent references cited by the identified studies. Controlled clinical trials are emphasized, but in many cases, data from randomized, controlled trials are lacking. In such cases, large case series, preliminary clinical studies, and expert opinions are used. Technical data are gathered from traditional and Web-based publications, proprietary publications, and informal communications with pertinent vendors. Technology Status Evaluation Reports are drafted by 1 or 2 members of the ASGE Technology Committee, reviewed and edited by the committee as a whole, and approved by the Governing Board of the ASGE. When financial guidance is indicated, the most recent coding data and list prices at the time of publication are provided. For this review, the MEDLINE database was searched through August 2010 for articles related to enteral, esophageal, duodenal, and colonic stents. Technology Status Evaluation Reports are scientific reviews provided solely for educational and informational purposes. Technology Status Evaluation Reports are not rules and should not be construed as establishing a legal standard of care or as encouraging, advocating, requiring, or discouraging any particular treatment or payment for such treatment. Copyright © 2011 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All rights reserved.

  7. Quality assurance of high-dose i.v. heparin treatment exemplified by patients implanted with coronary Palmaz-Schatz stents.

    Science.gov (United States)

    Haushofer, A; Halbmayer, W M; Prachar, H; Fischer, M

    1995-04-01

    The need to standardize treatment with high-dose IV standard heparin by using activated partial thromboplastin time (APTT) reagents tested for their heparin sensitivity and by establishing a standard treatment schedule led to the development of the "Lainz concept" of heparin management. The determination of heparin sensitivity of the 2 APTT reagents used (APTT Micronized Silica and APTT Actin FSL), their good agreement (r = .9977; P = .000), and their therapeutic APTT ratio of 1.5-2.5 fold of baseline APTT (therapeutic range, forty-five to seventy-five seconds) equivalent to 0.3-0.7 antifactor Xa units are presented. The "Lainz concept" was tested in 29 patients receiving high-dose heparin after coronary artery stenting. A mean dose of 1,273 U of standard heparin/hour (15.7 U/kg body