Renal Infarction Caused by Spontaneous Renal Artery Dissection: Treatment with Catheter-Directed Thrombolysis and Stenting

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Jeon, Yong Sun; Cho, Soon Gu; Hong, Ki Cheon

2009-01-01

Spontaneous renal artery dissection (SRAD) is rare and presents a diagnostic and therapeutic challenge. We report a case of a 36-year-old man who had an SRAD-complicated renal infarction. The patient experienced severe unilateral flank pain. Enhanced abdominal computed axial tomography scan showed renal infarction, and urinalysis showed no hematuria. Selective renal angiography was essential to evaluate the extent of dissection and suitability for repair. The patient was treated with catheter-directed thrombolysis and frenal artery stenting.

Accidental Coverage of Both Renal Arteries during Infrarenal Aortic Stent-Graft Implantation: Cause and Treatment

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Umberto Marcello Bracale

2014-01-01

Full Text Available The purpose of this paper is to report a salvage maneuver for accidental coverage of both renal arteries during endovascular aneurysm repair (EVAR of an infrarenal abdominal aortic aneurysm (AAA. A 72-year-old female with a 6 cm infrarenal abdominal aortic aneurysm was treated by endovascular means with a standard bifurcated graft. Upon completing an angiogram, both renal arteries were found to be accidentally occluded. Through a left percutaneous brachial approach, the right renal artery was catheterized and a chimney stent was deployed; however this was not possible for the left renal artery. A retroperitoneal surgical approach was therefore carried out with a retrograde chimney stent implanted to restore blood flow. After three months, both renal arteries were patent and renal function was not different from the baseline. Both endovascular with percutaneous access via the brachial artery and open retroperitoneal approaches with retrograde catheterization are feasible rescue techniques to recanalize the accidentally occluded renal arteries during EVAR.

Clinical effectiveness of secondary interventions for restenosis after renal artery stenting

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Simone, Thomas A.; Brooke, Benjamin S.; Goodney, Philip P.; Walsh, Daniel B.; Stone, David H.; Powell, Richard J.; Cronenwett, Jack L.; Nolan, Brian W.

2013-01-01

Objective Secondary interventions for renal artery restenosis (RAS) after renal artery stenting are common, despite limited data about their effectiveness. This study was designed to evaluate the outcomes of endovascular treatment of recurrent RAS. Methods We conducted a retrospective review of patients who underwent renal artery stenting between 2001 and 2011 at Dartmouth-Hitchcock Medical Center. Patients who required secondary interventions were compared with control patients who underwent only primary interventions for RAS. Multivariate regression models were used to identify factors associated with successful outcomes, as measured by changes in blood pressure, estimated glomerular filtration rate, and number of antihypertensive medications required. Results Sixty-five secondary (57 patients) renal interventions were undertaken for recurrent RAS associated with progressive hypertension or renal dysfunction and compared with outcomes after 216 primary (180 patients) renal artery stenting procedures. Patients undergoing primary vs secondary interventions did not differ significantly in the number of preoperative antihypertensive medications used, comorbid conditions, or blood pressure. All primary and secondary interventions were performed with stents and showed no difference in procedural complications. At a mean follow-up of 23 months (range, 1–128 months), similar improvements in renal function and blood pressure were found between patients undergoing primary and secondary interventions, and there was no difference in rates of restenosis or survival between cohorts. Regression models showed that the use of embolic protection devices was associated with improved renal function after primary (odds ratio [OR], 2.0; 95% confidence interval [CI], 1.1–3.8; P < .05) and secondary (OR, 4.7; 95% CI, 1.7–12.5; P < .05) interventions, whereas statin therapy was associated with improved renal (OR, 2.0; 95% CI, 1.3–3.2; P < .05) and blood pressure response (OR, 4

Reversal of end-stage renal disease after aortic dissection using renal artery stent: a case report

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Parikh Chirag R

2004-05-01

Full Text Available Abstract Background Medical management is the conventional treatment for Stanford Type B aortic dissections as surgery is associated with significant morbidity and mortality. The advent of endovascular interventional techniques has revived interest in treating end-organ complications of Type B aortic dissection. We describe a patient who benefited from endovascular repair of renal artery stenosis caused by a dissection flap, which resulted in reversal of his end-stage renal disease (ESRD. Case presentation A 69 y/o male with a Type B aortic dissection diagnosed two months earlier was found to have a serum creatinine of 15.2 mg/dL (1343.7 μmol/L on routine visit to his primary care physician. An MRA demonstrated a rightward spiraling aortic dissection flap involving the origins of the celiac artery, superior mesenteric artery, and both renal arteries. The right renal artery arose from the false lumen with lack of blood flow to the right kidney. The left renal artery arose from the true lumen, but an intimal dissection flap appeared to be causing an intermittent stenosis of the left renal artery with compromised blood flow to the left kidney. Endovascular reconstruction with of the left renal artery with stent placement was performed. Hemodialysis was successfully discontinued six weeks after stent placement. Conclusion Percutaneous intervention provides a promising alternative for patients with Type B aortic dissections when medical treatment will not improve the likelihood of meaningful recovery and surgery entails too great a risk. Nephrologists should therefore be aggressive in the workup of ischemic renal failure associated with aortic dissection as percutaneous intervention may reverse the effects of renal failure in this population.

Stent-Assisted Coil Embolization of a Mycotic Renal Artery Aneurysm by Use of a Self-Expanding Neurointerventional Stent

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Rabellino, Martin; García-Nielsen, Luis; Zander, Tobias; Baldi, Sebastián; Llorens, Rafael; Maynar, Manuel

2011-01-01

Mycotic aneurysms are uncommon, especially those located in visceral arteries. We present a case of a patient with two visceral mycotic aneurysms due to bacterial endocarditis, one located in right upper pole renal artery and the second in the splenic artery. Both aneurysms were treated as endovascular embolization using microcoils. In the aneurysm located at the renal artery, the technique of stent-assisted coils embolization was preferred to avoid coils migration due to its wide neck. The stent used was the Solitaire AB, which was designed for the treatment of intracranial aneurysms and was used recently in acute stroke as a mechanical thrombectomy device. Complete embolization of the aneurysm was achieved, preserving all the arterial branches without nephrogram defects in the final angiogram.

Long term results of endovascular treatment in renal arterial stenosis from Takayasu arteritis: Angioplasty versus stent placement

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Park, Hong Suk, E-mail: hongsukpark@gmail.com [Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Irwon-dong, Gangnam-gu, 135-710 Seoul (Korea, Republic of); Do, Young Soo, E-mail: ysdo@skku.edu [Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Irwon-dong, Gangnam-gu, 135-710 Seoul (Korea, Republic of); Park, Kwang Bo, E-mail: kbjh.park@samsung.com [Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Irwon-dong, Gangnam-gu, 135-710 Seoul (Korea, Republic of); Kim, Duk-Kyung, E-mail: dukkyung.kim@samsung.com [Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Irwon-dong, Gangnam-gu, 135-710 Seoul (Korea, Republic of); Choo, Sung Wook, E-mail: sw.choo@samsung.com [Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Irwon-dong, Gangnam-gu, 135-710 Seoul (Korea, Republic of); Shin, Sung Wook, E-mail: sw88.shin@samsung.com [Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Irwon-dong, Gangnam-gu, 135-710 Seoul (Korea, Republic of); Cho, Sung Ki, E-mail: sungkismc@samsung.com [Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Irwon-dong, Gangnam-gu, 135-710 Seoul (Korea, Republic of); Hyun, Dongho, E-mail: mesentery.hyun@samsung.com [Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Irwon-dong, Gangnam-gu, 135-710 Seoul (Korea, Republic of); Choo, In Wook, E-mail: inwook.choo@samsung.com [Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Irwon-dong, Gangnam-gu, 135-710 Seoul (Korea, Republic of)

2013-11-01

Purpose: To retrospectively evaluate and compare the long term patency and antihypertensive effect of angioplasty and stent insertion in renal artery stenosis caused by Takayasu arteritis, with CT angiography and clinical follow-up. Materials and methods: We retrospectively analyzed and compared effects on hypertension and patency of renal artery in 16 patients (age ranging from 16 to 58 years, mean: 32.1 years) with renovascular hypertension caused by Takayasu arteritis who underwent endovascular treatment including angioplasty (n = 13) and stent placement (n = 9) for 22 stenotic renal arteries. Results: Technical success was 95% (21/22) without major complications. In the last follow-up CT angiogram (mean 85 ± 41 months), restenosis was 8% (1/12) in angioplasty and 66% (6/9) in stent. Patency rates of angioplasty were 100%, 91.7%, 91.7% and primary unassisted and primary assisted patency rates of stent placement were 55.6%, 33.3%, 33.3% and 88.9%, 66.7%, 55.6% at 1-, 3- and 5-years, respectively. In clinical follow-up (mean 120 ± 37.8 months, range 48–183 months), beneficial effects on hypertension were obtained in 87% of patients (13/15) and there was no significant difference between the patients who were treated by only angioplasty and the patients who received stent placement in at least one renal artery, regardless of whether or not angioplasty had been performed in the other renal artery. Conclusion: Compared with stent placement, angioplasty demonstrated better long term patency and similar clinical benefit on renovascular hypertension in renal artery stenosis of Takayasu arteritis. We suggest that stent placement should be reserved for obvious angioplasty failure.

Endovascular repair of renal artery aneurysm with the multilayer stent – a short report

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Vojko Flis

2012-10-01

in the main left renal artery involving all three major branches of the renal artery. Via a percutaneous femoral approach a multilayer stent was deployed without complications. Blood flow inside the sac was immediately and significantly reduced. All the renal branches remained patent. Conclusion: New multilayer fluid modulating stent concept appears to be a very useful and attractive alternative to surgery or other endovascular techniques for those RAA involving or very close to major branch vessels, especially in patients with very high risk of loosing the only viable kidney, as in our case.

Stents in Renal Artery Bifurcation Stenosis: A Case Report

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Polytimi Leonardou

2011-01-01

Full Text Available A 39-year-old patient presented with poorly controlled hypertension, and she was referred to renal angiogram and potential renal angioplasty. Renal angiogram showed a bifurcation lesion of the right renal artery. A guide wire was used to cross the upper branch, while the lower branch was protected by another same-type guide wire through the same introducer. Two thin monorail balloons were used to dilate the two branches; however, despite balloon dilatation, the stenosis of the vessels persisted. The “kissing balloon” technique was then attempted by simultaneously inflating both branches using the same balloons, but more than a 70% residual stenosis persisted in each branch. Two stents were finally placed in a “kissing” way through the main renal artery. The imaging and clinical results were good, without any procedure-related complications. Three years clinical followup was also good, without any reason for further interventional approach.

Stents in Renal Artery Bifurcation Stenosis: A Case Report

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Leonardou, Polytimi; Pappas, Paris

2011-01-01

A 39-year-old patient presented with poorly controlled hypertension, and she was referred to renal angiogram and potential renal angioplasty. Renal angiogram showed a bifurcation lesion of the right renal artery. A guide wire was used to cross the upper branch, while the lower branch was protected by another same-type guide wire through the same introducer. Two thin monorail balloons were used to dilate the two branches; however, despite balloon dilatation, the stenosis of the vessels persisted. The “kissing balloon” technique was then attempted by simultaneously inflating both branches using the same balloons, but more than a 70% residual stenosis persisted in each branch. Two stents were finally placed in a “kissing” way through the main renal artery. The imaging and clinical results were good, without any procedure-related complications. Three years clinical followup was also good, without any reason for further interventional approach. PMID:21789043

The impact of renal artery stent revascularization on blood pressure: 1-year follow-up of 110 cases

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Wang Chao; Zou Yinghua; Yang Min; Wang Jian; Tong Xiaoqiang; Song Li

2007-01-01

Objective: To investigate the effect of renal artery revascularization through renal artery stenting(PTRAS)on blood pressure in patients with renal artery stenosis. Methods: During April 2000 through May 2005 110 cases of renal artery stenosis received PTRAS and followed up for at least 1 year with blood pressure measurements pre-and 1 year post-PTRAS. Results: The technical success rate was 100% for all 110 cases. The renal artery stenosis were decreased from 60%-100% before PTRAS to 0%-15% after the stent placement. There was significant difference between blood pressure pre-and 1 year post PTRAS. Systolic pressures decreased from(153 ± 32) mmHg to(131 ± 27) mmHg and diastolic pressures from(87 ± 19) mmHg to(75 ± 19) mmHg. The administration of antihypertensive diugs reduced from(2.6 ± 0.9 ) sorts to(1.9 ± 0.9) sorts. Conclusions: PTRAS revascularization is an effective procedure for blood pressure control in renal vascular hypertension during one year follow up. (authors)

Successful technical and clinical outcome using a second generation balloon expandable coronary stent for transplant renal artery stenosis: Our experience.

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Salsamendi, Jason; Pereira, Keith; Baker, Reginald; Bhatia, Shivank S; Narayanan, Govindarajan

2015-10-01

Transplant renal artery stenosis (TRAS) is a vascular complication frequently seen because of increase in the number of renal transplantations. Early diagnosis and management is essential to optimize a proper graft function. Currently, the endovascular treatment of TRAS using angioplasty and/or stenting is considered the treatment of choice with the advantage that it does not preclude subsequent surgical correction. Treatment of TRAS with the use of stents, particularly in tortuous transplant renal anatomy presents a unique challenge to an interventional radiologist. In this study, we present three cases from our practice highlighting the use of a balloon-expandable Multi-Link RX Ultra coronary stent system (Abbott Laboratories, Abbott Park, Illinois, USA) for treating high grade focal stenosis along very tortuous renal arterial segments. Cobalt-Chromium alloy stent scaffold provides excellent radial force, whereas the flexible stent design conforms to the vessel course allowing for optimal stent alignment.

Interventional treatment of transplanted renal artery stenosis

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Zhou Haihong; Chen Weiguo; Lu Wei; Chen Yong; Yan Xinmin; Zhou Jianyong; Li Yanhao

2002-01-01

Purpose: To evaluate the clinical application of percutaneous transluminal renal artery angioplasty (PTRA) in the treatment of transplanted renal artery stenosis. Methods: Nine patients with transplanted renal artery stenosis were treated by PTRA with balloon catheter through the f amoral artery. Metal stent was placed in 3 patients out of 9. Results: Technical success was obtained in all procedures. In 7 patients normal blood pressure was restored and serum creatinine remarkably decreased. But anti-hypertension drugs were still needed in rest 2 patients. Conclusion: PTRA and stent implantation are useful and valuable method in the treatment of transplanted renal artery stenosis

Efficacy of percutaneous transluminal renal angioplasty with stent in elderly male patients with atherosclerotic renal artery stenosis

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Zhao J

2012-10-01

Full Text Available Jiahui Zhao, Qingli Cheng, Xiaoying Zhang, Meihua Li, Sheng Liu, Xiaodan WangDepartment of Geriatric Nephrology, Chinese PLA General Hospital, Beijing, ChinaObjectives: Percutaneous transluminal renal angioplasty with stent implantation (PTRAS has become the treatment of choice for atherosclerotic renal artery stenosis (ARAS. This study evaluates the long-term effects of PTRAS on hypertension and renal function in elderly patients with ARAS.Methods: We conducted a retrospective cohort study of all patients who underwent PTRAS in the geriatric division of a tertiary medical center during the period 2003–2010. The clinical data were extracted from the medical records of each patient. Changes in blood pressure, antihypertensive treatment, and estimated glomerular filtration rate were analyzed before and after PTRAS.Results: Eighty-six stents in 81 elderly patients were placed successfully. The average age of the patients was 76.2 years (65–89 years. Mean follow-up was 31.3 months (range 12 –49 months. There was a significant decrease in both systolic and diastolic blood pressure at the third day after the PTRAS procedure and the reduction in blood pressure was constant throughout the follow-up period until 36 months after PTRAS. However, there was no marked benefit to renal function outcome during the follow-up period. The incidence of contrast-induced nephropathy was 9.9% in this study group. The rate of renal artery restenosis was 14.8%. The survival rate was 96.3% for 4 years after the procedure.Conclusion: It is beneficial to control blood pressure in elderly patients with ARAS up to 36 months after a PTRAS procedure. However, their renal function improvement is limited.Keywords: angioplasty, hypertension, renal function, elderly, renal artery stenosis

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

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

2005-01-01

To evaluate the technical feasibility of the implantation of the monorail RX Herculink system into the renal arteries without pre-dilatation. Forty-two patients (mean age 71 years) from four centers with a total of 44 renal artery stenoses underwent implantation of the RX Herculink 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). 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. Implantation of the RX Herculink 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.

Endovascular treatment of renal artery stenoses

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Lashari, M.N.

2015-01-01

To evaluate the procedure success and effect on hypertension after stenting of incidentally diagnosed atherosclerotic renal artery stenoses. Study Design: An experimental study. Place and Duration of Study: A multicentric study was conducted at the Plastic Surgery and General Hospital, National Medical Center and Ziauddin University Hospital, Karachi, Pakistan from January 2009 to March 2013. Methodology: Hypertension (systolic blood pressure > 160 and diastolic > 90 mmHg with two or more than two medications) with coronary artery disease were initially evaluated for coronary angiography, Renal artery angiography was also endovascular performed and stent was deployed for atherosclerotic renal artery stenosis when found. Blood pressure readings, reduction in need of antihypertensive medication and serum creatinine levels were taken as outcome measures. Patients having renal artery stenoses secondary to connective tissue disorders and fibromuscular dysplasia were excluded. Results: There were 25 patients, 14 (56%) male and 11 (44%) female, with mean age of 49 +- 6 years. Diabetes mellitus, dyslipidemia and smoking were seen in 11 (44%), 10 (40%) and 4 (16%) patients respectively. Renal insufficiency (serum creatinine > 1.5 mg/dl) was seen in one (04%) patient. Bilateral, and isolated right and left renal artery stenoses was seen in 5 (20%), 9 (36%) and 11(44%) patients respectively. Mean percentage of renal artery stenoses was 89%, ranged from 70% to 99% while ostial lesion was found in 20 (80%) patients. A significant decrease in systolic (168.20 +- 9.987 vs. 140.60 +- 5.649 mmHg, p < 0.001) and diastolic blood pressure (88.60 +- 5.50 vs. 77.20 +- 5.017 mmHg, p < 0.001) and reduction of medication (2.72 +- 0.458 vs. 1.5 +- 0.510, p < 0.01) were noted without a change in renal function (p= 0.061) after renal artery stenting. Conclusion: Endovascular stenting of renal artery stenoses in patients with poorly controlled hypertension is a safe and effective treatment

[Early results with a monorail-stent-balloon device for endovascular treatment of renal artery stenosis].

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Müller-Hülsbeck, S; Jahnke, T; Grimm, J; Behm, C; Hilbert, C; Frahm, C; Biederer, J; Brossmann, J; Heller, M

2002-03-01

To evaluate the technical feasibility of a new monorail-stent-balloon device for treatment of renal artery stenosis (RAS). During a study period of 18 months, 38 patients with proven RAS in 41 cases (hypertension n = 36, renal insufficiency n = 13) and indication for stenting (calicified ostial lesions n = 35, insufficient PTA n = 4, dissection n = 2) were enrolled into this prospective evaluation. Pre-mounted stents (Rx-Herculink(TM) 5 mm = 13, 6 mm = 34, 7 mm = 1) were implanted a transfemoral (n = 35) or transbrachial approach (n = 6). Mean grade and lengths of stenosis measured were 88 % plus minus 10 and 9 mm plus minus 5. Renal stent implantation was technically successful in all cases (100 %). In 7 cases a second stent had to be implanted to cover the entire lesion. The transstenotic pressure drop decreased from 88 mmHg plus minus 10 before to 1 mmHg plus minus 1.8 after the procedure. Remaining stenosis measured 0.7 % plus minus 4.2. Serum creatine levels decreased from 1.9 mm/dl to 1.5 mg/dl (n. s.), blood pressure decreased from 178/94 mmHg to 148/79 mmHg (p monorail-stend-balloon device a technically easy, secure and exact renal stent placement is guaranteed, patency rates are similar to those described in the current literature.

The Erasme Study: A Multicenter Study on the Safety and Technical Results of the Palmaz Stent Used for the Treatment of Atherosclerotic Ostial Renal Artery Stenosis

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Bakker, Jeannette; Goffette, Pierre P.; Henry, Michel; Mali, Willem P.T.M.; Melki, Jean-Pierre; Moss, Jon G.; Rabbia, Claudio; Therasse, Eric; Thomson, Kenneth R.; Thurnher, Siegfried; Vignali, Claudio

1999-01-01

Purpose: To assess, in a multicenter setting, safety, technical results, and restenosis rate of the Palmaz stent for treatment of atherosclerotic ostial renal artery stenosis. Methods: Ten centers enrolled 106 patients (120 treated renal artery stenoses) in the study. Patient selection was based on unsuccessful percutaneous transluminal renal angioplasty (residual stenosis ≥ 20%) performed for treatment of ostial stenosis ≥ 50%, in patients with hypertension and/or impaired renal function. Safety was assessed by means of the complication rate, and technical results by the number of successful stent placements and occurrence of restenosis (>50%) at intraarterial angiographic follow-up. Results: Stent placement was successful (n = 112) or partially successful (n = 5) in 117 (98%) arteries. Complications occurred in 19 procedures; seven were of serious clinical significance. Angiographic follow-up was performed in 89 of 117 (76%) cases, at a mean of 8 months (range 2.5-18 months). Fifteen stents (16.9%) showed restenosis (at a mean of 8.5 months), of which 10 were successfully redilated. Conclusion: Renal artery stenting has a high technical success rate, a complication rate comparable to percutaneous transluminal renal angioplasty, and a low rate of restenosis at 8 months angiographic follow-up

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.)

"The challenge facing renal artery revascularization: what have we not proven and why we must"?

LENUS (Irish Health Repository)

Hynes, B G

2012-01-04

Endovascular renal artery stent therapy for atherosclerotic renal artery stenosis (RAS) is associated with excellent acute technical success, low complication rates and acceptable long-term patency. However, the clinical benefits to patients of renal artery stenting remain uncertain. To facilitate debate regarding the treatment of RAS, we need to understand the epidemiology, basic physiology and clinical consequences of renal artery stenosis. We must attempt to determine which patients are likely to benefit from renal artery stenting, assess the nuances of the percutaneous procedure and review the current literature pertaining to renal artery stenting.

Low-profile stent placement with the monorail technique for treatment of renal artery stenosis: midterm results of a prospective trial.

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Müller-Hülsbeck, Stefan; Frahm, Christian; Behm, Charlotte; Schäfer, Phillip Jobst; Bolte, Hendrik; Heller, Martin; Jahnke, Thomas

2005-07-01

To determine feasibility, safety, and midterm patency of a monorail balloon stent device for the treatment of renal artery stenosis (RAS). During a period of 30 months, 47 patients (with severe hypertension, n=45; renal insufficiency, n=20) with 50 cases of RAS and indications for stent implantation (calcified ostial lesion, n=41; insufficient percutaneous transluminal angioplasty, n=6; dissection, n=3) were enrolled into the prospective evaluation. After predilation, 59 stents (Rx-Herculink 4 mm, n=2; 5 mm, n=19; 6 mm, n=35; 7 mm, n=3) were implanted under manometer control with use of the long-sheath technique (5 F; 6 F for 7-mm stents) via a femoral (n=44) or transbrachial approach (n=6). Parameters of hypertension and renal insufficiency were determined before and after the procedure and for a maximum of 18 months. Restenosis rate was determined with color duplex ultrasonography. Renal artery stent placement (mean diameter, 5.7 mm; mean length, 16 mm) was technically successful in all cases (100%). Mean blood pressure and serum creatinine level decreased from 177/93 mm Hg to 145/78 mm Hg and from 1.8 mg/dL to 1.5 mg/dL, respectively. Within 48 hours after the implantation, acute occlusions occurred in two patients, supposedly triggered by cholesterol embolization. Primary and primary assisted patency rates were 87% and 92% at 6 months and 75% and 84% at 18 months. Renal artery stent placement with the rapid-exchange monorail system is a safe procedure with promising patency rates. In combination with the long-sheath technique, adequate control of stent deployment is guaranteed during the entire intervention. The low profile of the device facilitates the use of small sheaths (5 F) to minimize access-site complications.

Early results with a monorail-stent-balloon device for endovascular treatment of renal artery stenosis

International Nuclear Information System (INIS)

Mueller-Huelsbeck, S.; Jahnke, T.; Grimm, J.; Behm, C.; Hilbert, C.; Frahm, C.; Biederer, J.; Brossmann, J.; Heller, M.

2002-01-01

Objective: To evaluate the technical feasibility of a new monorail-stent-balloon device for treatment of renal artery stenosis (RAS). Patients and Methods: During a study period of 18 months, 38 patients with proven RAS in 41 cases (hypertension n = 36, renal insufficiency n = 13) and indication for stenting (calicified ostial lesions n = 35, insufficient PTA n = 4, dissection n = 2) were enrolled into this prospective evaluation. Pre-mounted stents (Rx-Herculink TM 5 mm = 13, 6 mm = 34, 7 mm = 1) were implanted a transfermoral (n = 35) or transbrachial approach (n = 6). Mean grade and lengths of stenosis measured were 88% ±10 and 9 mm ±5. Results: Renal stent implantation was technically successful in all cases (100%). In 7 cases a second stent had to be implanted to cover the entire lesion. The transstenotic pressure drop decreased from 88 mmHg ± 10 before to 1 mmHg ± 1.8 after the procedure. Remaining stenosis measured 0.7% ±4.2. Serum creatine levels decreased from 1.9 mm/dl to 1.5 mg/dl (n.s.), blood pressure decreased from 178/94 mmHg to 148/79 mmHg (p [de

Interventional treatment of arterial complications in post renal transplantation

International Nuclear Information System (INIS)

Qian Xiaojun; Dai Dingke; Zhai Renyou

2004-01-01

Objective: To report our experience of interventional procedure for arterial complications in post renal transplantation and to evaluate its clinical value. Methods: In a retrospective analysis of renal transplantations in our center, 52 cases of renal allograft artery abnormalities had taken angiography. Interventional procedure included transluminal angioplasty of arterial stenoses, treatment of arterial occlusion, and embolization of pseudoaneurysm. Results: Renal allograft artery abnormalities included artery stenosis (n=21), artery thrombosis (n=13) and embolision (n=1), renal artery pseudoaneurysms (n=2), and decrease of renal artery flow (n=3). Of the 21 artery stenosis, 2 grafts with artery stenosis were lost because the stenosis could not be corrected, and 3 with mild stenosis received no treatment. Another 16 accepted renal artery angioplasty (balloon dilation, n=12, and stent implantation, n=4). 14 achieved long-term allograft function. 1 graft was lost because renal function failed to recover. Restenosis occurred in one stent implantation, and lost the allograft function after secondary dilation. 13 cases received thrombolytic therapy through artery catheter for thrombosis and 9 achieved long-term allograft function. Thrombolyses failed in 3 cases, and renal function failed to recover in 1 case. One pseudoaneurysm received stent implantation after embolization, and got a short-term allograft function. The other one received allograft excision. Conclusion: Intravascular interventional therapy will be the first-line therapy for any indications of complication in post renal transplantation, and it can surely save the kidney in a majority of instances. (authors)

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

International Nuclear Information System (INIS)

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

2011-01-01

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

Diabetes insipidus-like state complicating percutaneous transluminal renal stenting for transplant renal artery stenosis.

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Tian, Lu; He, Yangyan; Zhang, Hongkun; Wu, Ziheng; Li, Donglin; Chen, Shanwen

2014-07-01

To report the incidence, etiology, and treatments of diabetes insipidus-like state that complicate percutaneous transluminal renal stenting (PTRS) for transplant renal artery stenosis (TRAS). Data from 7 patients on whom PTRS for TRAS was performed between October 2008 and March 2012 were reviewed retrospectively. The parameters investigated included blood flow velocity, blood pressure, and creatinine levels before and after the intervention. The procedural success rate was 100%. Three cases developed a diabetes insipidus-like state in the immediate postprocedural period. Urine output returned to normal within 2 weeks after treatment. The median blood flow velocity was significantly reduced from 4.51 m/sec (4.31-4.61 m/sec) at the time of TRAS diagnosis to 1.33 m/sec (1.31-1.51 m/sec) at the most recent follow-up of the group with a diabetes insipidus-like state. The ratio of median blood flow velocity before and after stenting in the group with a diabetes insipidus-like state was significantly higher than that in the group without a diabetes insipidus-like state (3.39 vs. 1.93). Diabetes insipidus-like state that complicates PTRS for TRAS is not an uncommon event, but appears to be underreported in the medical literature. A high ratio of pre- and poststenting median blood flow velocity may be a predictor for a postprocedural diabetes insipidus-like state. The most probable cause may be the marked increase in renal arterial flow. Early recognition of the condition is essential to avoid dehydration and electrolyte imbalance. Copyright © 2014 Elsevier Inc. All rights reserved.

“Transcollateral” Renal Angioplasty for a Completely Occluded Renal Artery

International Nuclear Information System (INIS)

Chandra, Subash; Chadha, Davinder S.; Swamy, Ajay

2011-01-01

Percutaneous transluminal renal angioplasty with stenting has been effective in the control of hypertension, renal function, and pulmonary edema caused by atherosclerotic renal artery stenosis. However, the role of the procedure has not been fully established in the context of chronic total occlusion of renal artery. We report the successful use of this procedure in 57-year-old male patient who reported for evaluation of a recent episode of accelerated hypertension. A renal angiogram in this patient showed ostial stenosis of the right renal artery, which was filling by way of the collateral artery. Renal angioplasty for chronic total occlusion of right renal artery was successfully performed in a retrograde fashion through a collateral artery, thereby leading to improvement of renal function and blood pressure control.

Percutaneous renal angioplasty and stenting: application of embolic protection device in patients with normal renal function

International Nuclear Information System (INIS)

Tong Xiaoqiang; Yang Ming; Wang Jian; Song Li; Wang Chao; Lv Yongxing; Sun Hongliang; Zou Yinghua; Yin Ming

2007-01-01

Objective: To investigate the Value of embolic protection device (EPD)in renal artery stenting (RAS)for the patients with normal renal function. Methods: Total 24 patients (26 renal arteries) suffering from renal artery stenosis with normal serum creatinine were divided into two groups: EPD group (n12)and non-EPD group (n=12). Serum creatinine was calculated and analized statistically between the two groups, 1 month and 6months after stenting respectively, and followed by comparisons taking inside of each group and between both groups. Results: Serum creatinine of the EPD and non-EPD groups before, 1 month and 6 month after stenting were(99.18 ± 18.26) μmol/L, (101.73 ± 12.65) μmol/L, (96.82 ± 15.81) μmol/L and (100.18 ± 19.81) μmol/L, (107.36 ± 29.49) μmol/L, (127.64 ± 88.05) μmol/L, respectively; showing no significant difference inside each group individually (P>0.05), and also no statistically significant difference between the two groups (P>0.05). Conclusion: For the patients suffering from renal artery stenosis with normal serum creatinine, application of EPD may have no impact on renal function. Further evaluation is needed. (authors)

Feasibility of Angioplasty and Stenting for Abdominal Aortic Lesions Adjacent to Previously Stented Visceral Artery Lesions in Patients with Takayasu Arteritis

International Nuclear Information System (INIS)

Joseph, George; George, Paul V.; Pati, Purendra Kumar; Chandy, Sunil Thomas

2007-01-01

Two young female patients with Takayasu arteritis presented with symptomatic long-segment abdominal aortic stenosis in the vicinity of previously deployed celiac and renal artery stents that projected markedly into the narrowed aortic lumen. Crushing or distortion of the visceral artery stents during aortic angioplasty was avoided by performing simultaneous or alternating balloon dilatations in the aorta and in the visceral artery stents. Consequently, the visceral artery stents remained patent and shortened longitudinally, allowing unhindered deployment of Wallstents in the adjacent aorta and abolition of a pressure gradient across the aortic lesions. Access to side branches covered by the Wallstent was obtained without difficulty, enabling the performance of balloon dilatation in multiple side branches and ostial stent deployment in a renal artery. These techniques could increase the scope of endovascular therapy in the treatment of patients with Takayasu arteritis

The benefit of stent placement and blood pressure and lipid-lowering for the prevention of progression of renal dysfunction caused by atherosclerotic ostial stenosis of the renal artery. The STAR-study: rationale and study design.

NARCIS (Netherlands)

Bax, L.; Mali, W.P.Th.; Buskens, E.; Koomans, H.A.; Beutler, J.J.; Braam, B.; Beek, F.J.A.; Rabelink, T.J.; Postma, C.T.; Huysmans, F.T.M.; Deinum, J.; Thien, Th.; Schultze Kool, L.J.; Woittiez, A.J.J.; Kouwenberg, J.J.; Meiracker, A.H. van den; Pattynama, P.M.; Ven, P.J. van der; Vroegindeweij, D.; Doorenbos, C.J.; Aarts, J.; Kroon, A.A.; Leeuw, P.W. de; Haan, M.W. de; Engelshoven, J. van; Rutten, M.J.C.M.; Montfrans, G.A. van; Reekers, J.A.; Plouin, P.F.; Batide Alanore, A. La; Azizi, M.; Raynaud, A.; Harden, P.N.; Cowling, M.

2003-01-01

BACKGROUND: Atherosclerotic renal artery stenosis (ARAS) is associated with progressive loss of renal function and is one of the most important causes of renal failure in the elderly. Current treatment includes restoration of the renal arterial lumen by endovascular stent placement. However, this

Invasive assessment of renal artery atherosclerotic disease and resistant hypertension before renal sympathetic denervation.

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Ribichini, Flavio; Pighi, Michele; Zivelonghi, Carlo; Gambaro, Alessia; Valvo, Enrico; Lupo, Antonio; Vassanelli, Corrado

2013-01-01

Renal sympathetic denervation (RSD) is emerging as a new therapeutic option for patients with severe hypertension refractory to medical therapy. The presence of a renal artery stenosis may be both a cause of secondary hypertension and a contraindication to RSD if a renal artery stent is implanted; therefore, the definition of the functional importance of a renal artery stenosis in a patient with refractory hypertension is crucial. We describe the imaging and functional intravascular assessment of an angiographically severe stenosis of the renal artery in a patient with severe refractory hypertension, by means of intravascular ultrasound (IVUS), and measurement of the translesional pressure gradient with a pressure wire. Pressure wire examination excluded any severity of the stenosis, and IVUS showed the presence of a dissected plaque that resolved spontaneously after 3 months of intensive medical therapy and high-dose statin. Subsequently the patient was treated with RSD, achieving a significant effect on blood pressure control. Intravascular imaging and functional assessment of renal artery anatomy in patients with atherosclerotic disease may prove particularly suited to patients with refractory hypertension and multilevel vascular disease who are considered for endovascular therapies, either renal artery stenting or RSD.

A Systematic Review of Outcomes Following Percutaneous Transluminal Angioplasty and Stenting in the Treatment of Transplant Renal Artery Stenosis

NARCIS (Netherlands)

Ngo, A. T.; Markar, S. R.; de Lijster, M. S.; Duncan, N.; Taube, D.; Hamady, M. S.

2015-01-01

To evaluate outcomes following treatment of transplant renal artery stenosis by percutaneous transluminal angioplasty and stent insertion. A literature search was performed using Pubmed, MEDLINE, Embase, Wiley Interscience and the Cochrane Library databases. Outcome measures were glomerular

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

International Nuclear Information System (INIS)

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

2008-01-01

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

Renal embolic protection devices improve blood flow after stenting for atherosclerotic renal artery stenosis.

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Paul, Timir K; Lee, John H; White, Christopher J

2012-11-15

We sought to measure angiographic renal frame counts (RFC), as a quantitative angiographic assessment of renal blood flow, to evaluate microvascular compromise due to atheroembolism associated with RAS. Atheroembolism associated with renal artery stenting (RAS) has been implicated as a cause for worsening renal function following successful intervention. Use of a distal embolic protection device (EPD) during RAS has been shown to be safe with debris capture in a high percentage of cases. However, objective benefit for renal function with EPD has been difficult to demonstrate. A control group of 30 consecutive patients (33 kidneys) who underwent RAS without EPD were compared with 33 consecutive patients (33 kidneys) who underwent RAS with EPD using RFC measurement. The prestent and poststent mean RFC for the control group was 30.4 ± 12.1 vs. 23.7 ± 9.9 (P = 0.002) and for the EPD group it was 42.6 ± 12.6 vs. 28.3 ± 9.2 (P renal blood flow, manifested by a greater reduction of the RFC (Δ RFC) 14.2 ± 15.2 vs. 6.7 ± 11.7 (P = 0.03) compared with the control group. The use of an EPD was associated with a much larger improvement in renal blood flow (lower RFC) following RAS. This suggests that EPD's may be effective in preventing renal atheroembolic injury and that a controlled trial measuring the impact of EPD's on renal blood flow following RAS should be performed. Copyright © 2012 Wiley Periodicals, Inc.

Endovascular Exclusion of Renal Artery Aneurysm

International Nuclear Information System (INIS)

Andersen, Poul Erik; Rohr, Nils

2005-01-01

A patient who was operated for an abdominal aortic aneurysm 7 years earlier presented with recently discovered iliac and renal artery aneurysms. The renal artery had an angulation of 90 o , but the aneurysm was successfully excluded using a covered vascular stent graft placed over an extrastiff guidewire. Even in cases of complex anatomy of a renal aneurysm, endovascular treatment should be considered. With development of more flexible and low-profile endoprosthesis with accurate deployment, these have become more usable

Dynamic Geometric Analysis of the Renal Arteries and Aorta following Complex Endovascular Aneurysm Repair.

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Ullery, Brant W; Suh, Ga-Young; Kim, John J; Lee, Jason T; Dalman, Ronald L; Cheng, Christopher P

2017-08-01

Aneurysm regression and target vessel patency during early and mid-term follow-up may be related to the effect of stent-graft configuration on the anatomy. We quantified geometry and remodeling of the renal arteries and aneurysm following fenestrated (F-) or snorkel/chimney (Sn-) endovascular aneurysm repair (EVAR). Twenty-nine patients (mean age, 76.8 ± 7.8 years) treated with F- or Sn-EVAR underwent computed tomography angiography at preop, postop, and follow-up. Three-dimensional geometric models of the aorta and renal arteries were constructed. Renal branch angle was defined relative to the plane orthogonal to the aorta. End-stent angle was defined as the angulation between the stent and native distal artery. Aortic volumes were computed for the whole aorta, lumen, and their difference (excluded lumen). Renal patency, reintervention, early mortality, postoperative renal impairment, and endoleak were reviewed. From preop to postop, F-renal branches angled upward, Sn-renal branches angled downward (P renals exhibited increased end-stent angulation (12 ± 15°, P renals, whereas F-renals exhibited increased end-stent angulation (5 ± 10°, P renal stent patency was 94.1% and renal impairment occurred in 2 patients (6.7%). Although F- and Sn-EVAR resulted in significant, and opposite, changes to renal branch angle, only Sn-EVAR resulted in significant end-stent angulation increase. Longitudinal geometric analysis suggests that these anatomic alterations are primarily generated early as a consequence of the procedure itself and, although persistent, they show no evidence of continued significant change during the subsequent postoperative follow-up period. Copyright © 2017 Elsevier Inc. All rights reserved.

Nursing experience in clinical endovascular treatment for renal artery aneurysms

International Nuclear Information System (INIS)

Dong Yanfen; Pan Xiaoxia; Luan Shaoliang; Wei Ren

2012-01-01

Objective: To discuss the standardized clinical nursing measures for patients receiving endovascular treatment of renal artery aneurysms. Methods: The clinical data of 9 patients with renal artery aneurysm, who were admitted to authors' hospital during the period from Jan. 2010 to Aug. 2011 and received endovascular treatment, were retrospectively analyzed. The related nursing points as well as the received endovascular. Results: A total of 9 cases with renal artery aneurysm were treated nursing measures were summarized. Results: A total of 9 cases with renal artery aneurysm were with interventional management, including embolization (n = 6), stent implantation (n = 2) and stent implantation together with coil embolization (n = 1). The mean hospitalization time was (10±2) days. Postoperative retention of urine was observed in one patient and postoperative retroperitoneal hemorrhage occurred in another patient. Neither nursing-related nor operation-related complications occurred. Conclusion: Standardized perioperative nursing care for patients with renal artery aneurysm can surely help enhance the patient's tolerance to the surgery, and effectively prevent the complications. (authors)

Interventional treatment of renal artery stenosis: a mid-term evaluation of clinical efficacy

International Nuclear Information System (INIS)

Liu Jing; Zhang Xitong

2009-01-01

Objective: To assess the clinical efficacy of interventional management for the treatment of renal artery stenosis. Methods: Percutaneous transluminal balloon renal angioplasty and / or percutaneous transluminal renal artery stenting were performed in 47 patients with renal artery stenosis (55 stenosed arteries in total). A follow-up study on the blood pressure and renal function was conducted and the results were statistically analyzed. Results: Fifty-four stenosed renal arteries were successfully reopened, of which only percutaneous transluminal balloon angioplasty was adopted in 17 and percutaneous transluminal renal artery stenting in 37. One patient died during the procedure. A follow-up for a mean period of (2.5 ± 0.6) years was carried out. The blood pressure determined at one (n = 46), 6 (n = 46), 12 (n = 33) and 24 (n = 29) months after the treatment was significantly decreased when compared to that determined before the treatment (P < 0.01). The clinical effective rate was 89.13% (41 / 46), 72.73% (24 / 33) and 62.07% (18 / 29), respectively. After the therapy,the renal function was improved in 5, remained unchanged in 33 and became worse in 3 patients. The comparison of the post-operative renograms (obtained within 2 months) with the pre-operative ones showed that in eight patients there was an increase in renal blood flow with an improvement in renal function impairment, which took a turn from severe degree to mild or moderate degree. Nevertheless, severe impairment in renal blood flow remained in 3 patients. Conclusion: Percutaneous transluminal balloon renal angioplasty and percutaneous transluminal renal artery stenting are safe and effective treatments for the renal artery stenosis, which also has a beneficial effect on the related renal hypertension and renal insufficiency. (authors)

Renal artery entrapment by the diaphragmatic crus

International Nuclear Information System (INIS)

Thony, F.; Baguet, J.-P.; Rodiere, M.; Sessa, C.; Janbon, B; Ferretti, G.

2005-01-01

The aim of this study is to describe renal artery entrapment (RAE) by the diaphragmatic crus and to elucidate the diagnostic and therapeutic approach to this entity. From 1995 to 2002, 15 patients (mean age 65) were found to have a RAE. They were investigated by CT scan (n=14) and/or MRA (n=2) for hypertension (n=7), chronic renal insufficiency (n=4) or aneurysms (n=4). The right (n=11) or the left (n=4) renal artery (RA) was involved. The compression was ostial (n=8) or truncal (n=7), and was ≥50% in eight cases. The course of the RA along the aorta on angiographic views (n=8) or a concentric ostial stenosis in a patient free of atheromatous lesions (n=7) were two findings suggestive of an RAE. Seven RAEs were indicated for treatment but only three were treated, by mean of stenting. Among the latter, two stents were patent at 6-month follow-up and one evolved to restenosis because of a stent fracture. RAEs may be suspected on angiographic views and proved by cross-sectional imaging because of specific imaging features. It is of importance to detect this etiology of RA stenosis because angioplasty with stenting is probably not always advisable. (orig.)

Close to Transplant Renal Artery Stenosis and Percutaneous Transluminal Treatment

Directory of Open Access Journals (Sweden)

Leonardou Polytimi

2011-01-01

Full Text Available Purpose. To evaluate the efficacy of percutaneous transluminal angioplasty (PTA in the management of arterial stenosis located close to the allograft anastomosis (close-TRAS. Materials and Methods. 31 patients with renal transplants were admitted to our institution because of persistent hypertension and impairment of transplant renal function and underwent angiography for vascular investigation. 27 were diagnosed suffering from transplant renal artery stenosis (TRAS, whereas 4 had severe iliac artery stenosis proximal to the transplant anastomosis (Prox-TRAS. 3 cases of TRAS coexisted with segmental renal arterial stenosis, whereas 3 other cases of TRAS were caused by kinking and focal stenosis in the middle of the transplanted renal artery. Results. Angioplasty and stenting were successfully applied to all patients with iliac artery stenosis as well as to those with TRAS and segmental artery stenosis. Two of three patients with kinking were well treated with angioplasty and stenting, whereas one treated only with angioplasty necessitated surgery. No major procedure-related complications appeared, and the result was decrease of the serum creatinine level and of the blood pressure. Conclusions. PTA is the appropriate initial treatment of TRAS and close-TRAS, with low morbidity and mortality rates, achieving improvement of graft function and amelioration of hypertension.

How to manage hypertension with atherosclerotic renal artery stenosis?

Science.gov (United States)

Ricco, Jean-Baptiste; Belmonte, Romain; Illuminati, Guilio; Barral, Xavier; Schneider, Fabrice; Chavent, Bertrand

2017-04-01

The management of atherosclerotic renal artery stenosis (ARAS) in patients with hypertension has been the topic of great controversy. Major contemporary clinical trials such as the Cardiovascular Outcomes for Renal Artery lesions (CORAL) and Angioplasty and Stenting for Renal Atherosclerotic lesions (ASTRAL) have failed to show significant benefit of revascularization over medical management in controlling blood pressure and preserving renal function. We present here the implications and limitations of these trials and formulate recommendations for management of ARAS.

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

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

Suprarenal fixation barbs can induce renal artery occlusion in endovascular aortic aneurysm repair.

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Subedi, Shree K; Lee, Andy M; Landis, Gregg S

2010-01-01

Renal artery occlusion following endovascular abdominal aortic aneurysm repair with suprarenal fixation is uncommon. We report one patient who was found to develop renal artery occlusion and parenchymal infarction 6 months after repair using an endovascular graft with suprarenal fixation. Our patient underwent emergent endovascular repair of a symptomatic 6 cm abdominal aortic aneurysm. The covered portion of the endograft was inadvertently deployed well below the renal artery orifices. At the completion of the procedure both renal arteries were confirmed to be patent. One month postoperatively, a computed tomographic (CT) scan showed exclusion of the aortic sac and normal enhancement of both kidneys. At 6 months, the patient was found to have elevated serum creatinine levels despite having no clinical symptoms. CT scanning revealed a nonenhancing left kidney, and angiography demonstrated an occlusion of the left renal artery. A barb welded to the bare metal stent appeared to be impinging on the renal artery. We believe that renal artery occlusion after endovascular repair can occur due to repetitive injury to the renal artery orifice from barbs welded to the bare metal stent. To our knowledge, this is the first reported case of renal artery occlusion caused by repetitive injury from transrenal fixation systems. Copyright 2010 Annals of Vascular Surgery Inc. Published by Elsevier Inc. All rights reserved.

Evaluation of the efficacy and safety of endovascular management for transplant renal artery stenosis

Directory of Open Access Journals (Sweden)

Leonardo G.M. Valle

Full Text Available OBJECTIVES: To evaluate the safety and efficacy of endovascular intervention with angioplasty and stent placement in patients with transplant renal artery stenosis. METHODS: All patients diagnosed with transplant renal artery stenosis and graft dysfunction or resistant systemic hypertension who underwent endovascular treatment with stenting from February 2011 to April 2016 were included in this study. The primary endpoint was clinical success, and the secondary endpoints were technical success, complication rate and stent patency. RESULTS: Twenty-four patients with transplant renal artery stenosis underwent endovascular treatment, and three of them required reinterventions, resulting in a total of 27 procedures. The clinical success rate was 100%. All graft dysfunction patients showed decreased serum creatinine levels and improved estimated glomerular filtration rates and creatinine levels. Patients with high blood pressure also showed improved control of systemic blood pressure and decreased use of antihypertensive drugs. The technical success rate of the procedure was 97%. Primary patency and assisted primary patency rates at one year were 90.5% and 100%, respectively. The mean follow-up time of patients was 794.04 days after angioplasty. CONCLUSION: Angioplasty with stent placement for the treatment of transplant renal artery stenosis is a safe and effective technique with good results in both the short and long term.

Successful angioplasty of tripolar renal arteries in a single setting: a case report.

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Sharma, Gyarsi Lal; Morice, Marie-Claude; Catineau, Patrick

2002-08-01

Renal artery stenosis (RAS) is one of the important causes of correctable hypertension. There are various modes of therapy for RAS, including percutaneous transluminal renal angioplasty (PTRA) and surgery. PTRA has emerged as the treatment of choice in cases of renal artery stenosis. PTRA combined with stenting is associated with good immediate and long-term results. This case report describes successful angioplasty of bilateral multiple renal arteries in a single setting with good immediate and follow-up results.

Stent revascularization restores cortical blood flow and reverses tissue hypoxia in atherosclerotic renal artery stenosis but fails to reverse inflammatory pathways or glomerular filtration rate.

Science.gov (United States)

Saad, Ahmed; Herrmann, Sandra M S; Crane, John; Glockner, James F; McKusick, Michael A; Misra, Sanjay; Eirin, Alfonso; Ebrahimi, Behzad; Lerman, Lilach O; Textor, Stephen C

2013-08-01

Atherosclerotic renal artery stenosis (ARAS) is known to reduce renal blood flow, glomerular filtration rate (GFR) and amplify kidney hypoxia, but the relationships between these factors and tubulointerstitial injury in the poststenotic kidney are poorly understood. The purpose of this study was to examine the effect of renal revascularization in ARAS on renal tissue hypoxia and renal injury. Inpatient studies were performed in patients with ARAS (n=17; >60% occlusion) before and 3 months after stent revascularization, or in patients with essential hypertension (n=32), during fixed Na(+) intake and angiotensin converting enzyme/angiotensin receptors blockers Rx. Single kidney cortical, medullary perfusion, and renal blood flow were measured using multidetector computed tomography, and GFR by iothalamate clearance. Tissue deoxyhemoglobin levels (R(2)*) were measured by blood oxygen level-dependent MRI at 3T, as was fractional kidney hypoxia (percentage of axial area with R(2)*>30/s). In addition, we measured renal vein levels of neutrophil gelatinase-associated lipocalin, monocyte chemoattractant protein-1, and tumor necrosis factor-α. Pre-stent single kidney renal blood flow, perfusion, and GFR were reduced in the poststenotic kidney. Renal vein neutrophil gelatinase-associated lipocalin, tumor necrosis factor-α, monocyte chemoattractant protein-1, and fractional hypoxia were higher in untreated ARAS than in essential hypertension. After stent revascularization, fractional hypoxia fell (Pblood flow, whereas GFR and neutrophil gelatinase-associated lipocalin, monocyte chemoattractant protein-1, and tumor necrosis factor-α remained unchanged. These data demonstrate that despite reversal of renal hypoxia and partial restoration of renal blood flow after revascularization, inflammatory cytokines and injury biomarkers remained elevated and GFR failed to recover in ARAS. Restoration of vessel patency alone failed to reverse tubulointerstitial damage and partly

Atherosclerotic renal artery stenosis is associated with elevated cell cycle arrest markers related to reduced renal blood flow and postcontrast hypoxia.

Science.gov (United States)

Saad, Ahmed; Wang, Wei; Herrmann, Sandra M S; Glockner, James F; Mckusick, Michael A; Misra, Sanjay; Bjarnason, Haraldur; Lerman, Lilach O; Textor, Stephen C

2016-11-01

Atherosclerotic renal artery stenosis (ARAS) reduces renal blood flow (RBF), ultimately leading to kidney hypoxia and inflammation. Insulin-like growth factor binding protein-7 (IGFBP-7) and tissue inhibitor of metalloproteinases-2 (TIMP-2) are biomarkers of cell cycle arrest, often increased in ischemic conditions and predictive of acute kidney injury (AKI). This study sought to examine the relationships between renal vein levels of IGFBP-7, TIMP-2, reductions in RBF and postcontrast hypoxia as measured by blood oxygen level-dependent (BOLD) magnetic resonance imaging. Renal vein levels of IGFBP-7 and TIMP-2 were obtained in an ARAS cohort (n= 29) scheduled for renal artery stenting and essential hypertensive (EH) healthy controls (n = 32). Cortical and medullary RBFs were measured by multidetector computed tomography (CT) immediately before renal artery stenting and 3 months later. BOLD imaging was performed before and 3 months after stenting in all patients, and a subgroup (N = 12) underwent repeat BOLD imaging 24 h after CT/stenting to examine postcontrast/procedure levels of hypoxia. Preintervention IGFBP-7 and TIMP-2 levels were elevated in ARAS compared with EH (18.5 ± 2.0 versus 15.7 ± 1.5 and 97.4 ± 23.1 versus 62.7 ± 9.2 ng/mL, respectively; Pblood flow (r = -0.59, P= 0.004). These data demonstrate elevated IGFBP-7 and TIMP-2 levels in ARAS as a function of the degree of reduced RBF. Elevated baseline IGFBP-7 levels were associated with protection against postimaging hypoxia, consistent with 'ischemic preconditioning'. Despite contrast injection and stenting, AKI in these high-risk ARAS subjects with elevated IGFBP-7/TIMP-2 was rare and did not affect long-term kidney function. © The Author 2016. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.

Saccular aneurysm of segmental branch of the main renal artery: approach to diagnosis and treatment

International Nuclear Information System (INIS)

Karaman, B.; Hamcan, S.; Bozkurt, Y.; Kara, K.; Aslan, A.

2012-01-01

Full text: Introduction: Renal artery aneurysms rarely detected clinical situation. Mostly determined by symptoms such as hematuria, hypertension and flank pain. Generally detected during investigation of symptoms or incidentally. Objectives and tasks: We aim to present the findings of CTA and DSA of the 58-year-old male patient with flank pain, hematuria and hypertension complaints. Materials and methods: We performed CTA and selective renal angiography to 58-year-old male patient with complaints of hypertension, flank pain and hematuria. Results: Approximately 11.5x 13.5 mm size of saccular aneurysm at the upper segmental branch of the left renal artery and focal cortical infarct detected in CT abdomen of the patient before treatment. The aneurysm was confirmed with selective renal angiography examination and treated with Cardiatis stent in the same procedure. Conclusion: Primary goal of treatment of renal artery aneurysms is to prevent complications such as rupture and thrombosis. Renal artery aneurysms have been treated with open surgery previously. Parenchyma preventive and minimally invasive treatments such as Cardiatis stent placement successfully uses currently

Distal Embolic Protection for Renal Arterial Interventions

International Nuclear Information System (INIS)

Dubel, Gregory J.; Murphy, Timothy P.

2008-01-01

Distal or embolic protection has intuitive appeal for its potential to prevent embolization of materials generated during interventional procedures. Distal protection devices (DPDs) have been most widely used in the coronary and carotid vascular beds, where they have demonstrated the ability to trap embolic materials and, in some cases, to reduce complications. Given the frequency of chronic kidney disease in patients with renal artery stenosis undergoing stent placement, it is reasonable to propose that these devices may play an important role in limiting distal embolization in the renal vasculature. Careful review of the literature reveals that atheroembolization does occur during renal arterial interventions, although it often goes undetected. Early experience with DPDs in the renal arteries in patients with suitable anatomy suggests retrieval of embolic materials in approximately 71% of cases and renal functional improvement/stabilization in 98% of cases. The combination of platelet inhibition and a DPD may provide even greater benefit. Given the critical importance of renal functional preservation, it follows that everything that can be done to prevent atheroembolism should be undertaken including the use of DPDs when anatomically feasible. The data available at this time support a beneficial role for these devices

Interventional therapy of atherosclerotic renal artery occlusion

International Nuclear Information System (INIS)

Li Jian; Xu Ke; Xiao Liang

2009-01-01

Objective: To investigate the effectiveness of interventional therapy for the atherosclerotic renal artery occlusion (ARAO). Methods: During the period of June 2001-Dec. 2007, 16 patients with ARAO (total of 16 occluded arteries) underwent interventional managements, including percutaneous endovascular renal artery revascularization, balloon dilatation angioplasty and stent placement. Follow-up survey was made at regular intervals. The patent condition of the renal artery was evaluated with ultrasonography and digital subtraction angiography. The blood pressure and the renal function were determined and the data were statistically analyzed in order to assess the intermediate and long-term effect of the interventional therapy. Results: Of 16 patients, technical success was achieved in 15 (93.8%) and failure occurred in one. During a follow-up period of 9 - 24 months, 3 patients died. According to the data obtained at each patient's last follow-up survey, the hypertension fell to normal in 3 (25.0%), was improved in 7 (58.3%) and showed no marked change in 2 patients (16.7%), with a clinical efficacy of 83.3% (10 / 12). The renal function was improved in 2 (16.7%), stabilized in 6 (50%) and deteriorated in 4 patients (33.3%), with an effective rate of 66.7% (8 / 12). Conclusion: For the treatment of atherosclerotic renal artery occlusion, the interventional therapy carries high successful rate and can effectively lower the blood pressure level, in addition, it can also protect the renal function in a certain degree. (authors)

Hemodynamic Measurements for the Selection of Patients With Renal Artery Stenosis: A Systematic Review

NARCIS (Netherlands)

van Brussel, Peter M.; van de Hoef, Tim P.; de Winter, Robbert J.; Vogt, Liffert; van den Born, Bert-Jan

2017-01-01

Interventions targeting renal artery stenoses have been shown to lower blood pressure and preserve renal function. In recent studies, the efficacy of catheter-based percutaneous transluminal renal angioplasty with stent placement has been called into question. In the identification of functional

Anatomic study of juxta renal aneurysms: impact on fenestrated stent-grafts.

Science.gov (United States)

Azzaoui, Richard; Sobocinski, Jonathan; Maurel, Blandine; D'Elia, Piervito; Perrot, Céline; Bianchini, Aurélia; Guillou, Matthieu; Haulon, Stéphan

2011-04-01

Fenestrated stent-grafts allow for treatment of patients with juxtarenal aneurysms (JRA) when they present with contraindications for conventional treatment. The fenestrated module is a custom-made module, specially designed to fit a specific patient, using computed tomographic scan measurements, which entails manufacturing delay and high cost. The aim of our study was to evaluate the possibility to reproduce the interrenal aorta anatomy to design a standard fenestrated module that would fit the maximum number of patients with JRA. On a three-dimensional working station, we analyzed 289 preoperative computed tomographic scan results of patients with JRA and who were treated with fenestrated stent-grafts comprising two fenestrations for the renal arteries and a scallop for the superior mesenteric artery (SMA). On curvilinear reconstructions, we successively measured the interrenal aorta diameter, its orientation, as well as the height of each renal ostium, taking the ostium center of the SMA as a reference mark. Later, a statistical analysis of these measures distribution was performed so as to design a fenestrated module that would fit the maximum number of patients. The center of the left renal artery presented with a median orientation of 82.5° (range, 37.5-150) and a median distance of 9 mm (range, 0-30), in relation to the SMA ostium. The ostium center of the right renal artery presented with a median orientation of 285° (range, 240-337.5) and a median distance of 8 mm (range, 3-30), in relation to the SMA ostium. By positioning the current renal fenestrations (6-mm wide), on the basis of the calculated median positions, in our series, only 20% of the patients could be treated with a standard fenestrated module. Should the diameter of these fenestrations be increased by 10 mm, it would then be possible to treat 50% of our patients. The anatomy of the interrenal aorta and its branches is quite reproducible to design standard fenestrated stent-grafts that could

Extra-anatomic bypass for recurrent abdominal aortic and renal in-stent stenoses following radiotherapy for neuroblastoma.

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Luehr, Maximilian; Siepe, Matthias; Beyersdorf, Friedhelm; Schlensak, Christian

2009-04-01

We describe the case of an 11-year-old girl with an abdominal neuroblastoma which was operated and intraoperatively irradiated nine years ago. After six years, she developed stenoses of the infrarenal abdominal aorta and both renal arteries. Initial treatment of the stenosed vessels comprised endovascular balloon dilatations and repeated stent-graft implantations, including drug eluting stents. However, severe in-stent stenoses occurred during follow-up and the girl developed acute renal failure. Open surgery was performed with two extra-anatomic bypasses, a thoracic-to-abdominal aortic bypass and a left iliac-to-renal bypass, on an urgent basis. The postoperative course was uneventful and the patient was discharged home two weeks after the operation with full recovery of renal function. We conclude that endovascular stent-graft placement in children can only be a palliative treatment due to outgrowing of the stent-graft and the potential risk of re-stenosis, especially after a history of irradiation. Vascular surgery with placement of extra-anatomic bypasses will provide a definite treatment.

Renal angioplasty for atherosclerotic renal artery stenosis: Cardiologist′s perspective

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A S Gulati

2013-01-01

Full Text Available Atherosclerotic renal artery stenosis (ARAS is frequently associated with concomitant coronary and peripheral arterial disease with a significant impact on cardiovascular morbidity and mortality. Renal angioplasty of ARAS is more challenging because of increased incidence of technical failures, complications, and restenosis; while there is barely perceptible control of hypertension and only marginal improvement in renal function. This is because most of the patient population in recent randomized trials had unmanifested or clinically silent renovascular disease. Manifestations of RAS should be looked for and incorporated in the management plan particularly before deciding for revascularization. In the absence of clinical manifestation like renovascular hypertension, ischemic nephropathy, left ventricular failure, or unstable coronary syndromes; mere presence of RAS is analogous to presence of concomitant peripheral arterial disease which increases risk of adverse coronary events. Dormant-RAS in the absence of any manifestations can be managed with masterly inactivity. Chronological sequence of events and clinical condition of the patient help in decision making by identifying progressive renovascular disease. Selecting patients for renal artery stenting who actually will benefit from revascularization shall also decrease the unnecessary complications inherent with any interventional procedure. The present review is an attempt to analyze the current view on the diagnostic and management issues more specifically about the need and rationale behind angioplasty.

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

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Matthias C. Burg

2011-01-01

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

Salvage of bilateral renal artery occlusion after endovascular aneurysm repair with open splenorenal bypass

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Samuel Jessula, MDCM

2017-09-01

Full Text Available We report renal salvage maneuvers after accidental bilateral renal artery coverage during endovascular aneurysm repair of an infrarenal abdominal aortic aneurysm. A 79-year-old man with an infrarenal abdominal aortic aneurysm was treated with endovascular aneurysm repair. Completion angiography demonstrated coverage of the renal arteries. Several revascularization techniques were attempted, including endograft repositioning and endovascular stenting through the femoral and brachial approach. The patient eventually underwent open splenorenal bypass with a Y Gore-Tex graft (W. L. Gore & Associates, Flagstaff, Ariz. After 3 months, computed tomography showed no evidence of endoleak and patent renal arteries. Renal function was well maintained, and the patient did not require dialysis.

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

International Nuclear Information System (INIS)

Zhao Huipin; Li Shenmao; Zhang Guangping

2010-01-01

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

Preliminary Report of Carotid Artery Stenting Using a Tapered Stent

Energy Technology Data Exchange (ETDEWEB)

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

2011-10-15

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

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

International Nuclear Information System (INIS)

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

2010-01-01

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

Retinal artery occlusion during carotid artery stenting with distal embolic protection device.

Science.gov (United States)

Kohara, Kotaro; Ishikawa, Tatsuya; Kobayashi, Tomonori; Kawamata, Takakazu

2018-01-01

Retinal artery occlusion associated with carotid artery stenosis is well known. Although it can also occur at the time of carotid artery stenting, retinal artery occlusion via the collateral circulation of the external carotid artery is rare. We encountered two cases of retinal artery occlusion that were thought to be caused by an embolus from the external carotid artery during carotid artery stenting with a distal embolic protection device for the internal carotid artery. A 71-year-old man presented with central retinal artery occlusion after carotid artery stenting using the Carotid Guardwire PS and a 77-year-old man presented with branch retinal artery occlusion after carotid artery stenting using the FilterWire EZ. Because additional new cerebral ischaemic lesions were not detected in either case by postoperative diffusion-weighted magnetic resonance imaging, it was highly likely that the debris that caused retinal artery occlusion passed through not the internal carotid artery but collaterals to retinal arteries from the external carotid artery, which was not protected by a distal embolic protection device. It is suggested that a distal protection device for the internal carotid artery alone cannot prevent retinal artery embolisation during carotid artery stenting and protection of the external carotid artery is important to avoid retinal artery occlusion.

Rupture of the Renal Artery After Cutting Balloon Angioplasty in a Young Woman With Fibromuscular Dysplasia

International Nuclear Information System (INIS)

Oguzkurt, Levent; Tercan, Fahri; Gulcan, Oner; Turkoz, Riza

2005-01-01

A 24-year-old woman with uncontrollable high blood pressure for 3 months had significant stenosis of the left renal artery caused by fibromuscular dysplasia (FMD). The lesion was resistant to percutaneous transluminal angioplasty at 18 atm with a semicompliant balloon. Angioplasy with a 6 x 10 mm cutting balloon (CB) caused rupture of the artery. Low-pressure balloon inflation decreased but did not stop the leak. An attempt to place a stent-graft (Jostent; Jomed, Rangendingen, Germany) failed, and a bare, 6-mm balloon-expandable stent (Express SD; Boston Scientific, MN) was deployed to seal the leak, which had decreased considerably after long-duration balloon inflation. The bleeding continued, and the patient underwent emergent surgical revascularization of the renal artery with successful placement of a 6-mm polytetrafluoroethylene bypass graft. CBs should be used very carefully in the treatment of renal artery stenosis, particularly in patients with FMD

Angioplasty and stent placement - peripheral arteries

Science.gov (United States)

... medlineplus.gov/ency/article/007393.htm Angioplasty and stent placement - peripheral arteries To use the sharing features ... inside the arteries and block blood flow. A stent is a small, metal mesh tube that keeps ...

Orbital Atherectomy in the Renal Artery: A New Frontier for an Emerging Technology?

Science.gov (United States)

Valle, Javier A; Armstrong, Ehrin J; Waldo, Stephen W

2017-01-01

Orbital atherectomy has been developed as a method to modify calcified plaque in the peripheral vasculature, with extensive experience and data supporting its use in infrainguinal peripheral arterial disease. However, calcific atherosclerotic disease occurs in other vascular beds and may benefit from the application of this technology. In this case report, we describe the first reported use of orbital atherectomy in a renal artery. A 55-year-old male with severe drug-refractory hypertension was found to have renal artery stenosis, with severe calcification of the right renal artery. Orbital atherectomy was utilized for initial plaque modification, and he underwent stenting of the renal artery lesion with an excellent angiographic and clinical result at follow-up. In conclusion, orbital atherectomy is a safe and effective means of plaque modification for severely calcified lesions. The safe and effective use of orbital atherectomy in the renal vasculature suggests an opportunity for ongoing evaluation into expanded roles for this technology beyond the coronary and lower-extremity arterial beds.

Endovascular rescue from arterial rupture and thrombosis during middle cerebral artery stenting

Energy Technology Data Exchange (ETDEWEB)

Ahn, J.Y.; Chung, Y.S. [Department of Neurosurgery, College of Medicine, Pundang CHA Hospital, 351 Yatap-ding, Pundang-gu, 463-712, Sungnam (Korea); Lee, B.H. [Department of Interventional Neuroradiology, College of Medicine, Pundang CHA Hospital, 351 Yatap-dong, Pundang-gu, 463-712, Sungnam (Korea); Kim, O.J. [Department of Emergency Medicine, College of Medicine, Pundang CHA Hospital, 351 Yatap-dong, Pundang-gu, 463-712, Sungnam (Korea)

2003-08-01

Intravascular stents are being used with increasing frequency in interventional neuroradiology. Iatrogenic arterial rupture is an uncommon but serious complication. We present a case of arterial rupture and subarachnoid haemorrhage during middle cerebral artery stenting, treated by emergency additional, overlapping stenting and balloon tamponade of the dissected vessel. Thrombotic occlusion of the artery was managed by intra-arterial abciximab. Normal vessel patency was re-established within 20 min and the patient recovered with no neurological deficit. (orig.)

Spontaneous Renal Artery Dissection in a Patient with Neurofibromatosis Type I

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Nicolas W. Shammas

2016-01-01

Full Text Available We present a case of spontaneous renal artery dissection (SRAD in a 28-year-old female with history of neurofibromatosis type I (NF-1 treated successfully with endovascular stenting. The clinical presentation, diagnostic testing, and treatment options are discussed. An endovascular approach with stenting was successfully performed after failure of medical treatment with subcutaneous low molecular weight heparin. Patient’s blood pressure and symptoms improved significantly. This may be the first reported case of SRAD in a patient with NF-1 successfully treated with endovascular stenting.

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

Energy Technology Data Exchange (ETDEWEB)

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

2014-12-15

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

Angioplasty and stent placement - carotid artery

Science.gov (United States)

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

Angioplasty and stent placement - peripheral arteries - discharge

Science.gov (United States)

... medlineplus.gov/ency/patientinstructions/000234.htm Angioplasty and stent placement - peripheral arteries - discharge To use the sharing ... peripheral artery). You may have also had a stent placed. To perform the procedure: Your doctor inserted ...

Oversizing and Restenosis with Self-Expanding Stents in Iliofemoral Arteries

International Nuclear Information System (INIS)

Saguner, Ardan M.; Traupe, Tobias; Räber, Lorenz; Hess, Nina; Banz, Yara; Saguner, Arhan R.; Diehm, Nicolas; Hess, Otto M.

2012-01-01

Purpose: Uncoated self-expanding nitinol stents (NS) are commonly oversized in peripheral arteries. In current practice, 1-mm oversizing is recommended. Yet, oversizing of NS may be associated with increased restenosis. To provide further evidence, NS were implanted in porcine iliofemoral arteries with a stent-to-artery-ratio between 1.0 and 2.3. Besides conventional uncoated NS, a novel self-expanding NS with an antiproliferative titanium-nitride-oxide (TiNOX) coating was tested for safety and efficacy. Methods: Ten uncoated NS and six TiNOX-coated NS (5–6 mm) were implanted randomly in the iliofemoral artery of six mini-pigs. After implantation, quantitative angiography (QA) was performed for calculation of artery and minimal luminal diameter. Follow-up was performed by QA and histomorphometry after 5 months. Results: Stent migration, stent fracture, or thrombus formation were not observed. All stents were patent at follow-up. Based on the location of the stent (iliac/femoral) and the stent-to-artery-ratio, stent segments were divided into “normal-sized” (stent-to-artery-ratio < 1.4, n = 12) and “oversized” (stent-to-artery-ratio ≥ 1.4, n = 9). All stent segments expanded to their near nominal diameter during follow-up. Normal-sized stent segments increased their diameter by 6% and oversized segments by 29%. A significant correlation between oversizing and restenosis by both angiography and histomorphometry was observed. Restenosis rates were similar for uncoated NS and TiNOX-coated NS. Conclusions: TiNOX-coated NS are as safe and effective as uncoated NS in the porcine iliofemoral artery. All stents further expand to near their nominal diameter during follow-up. Oversizing is linearly and positively correlated with neointimal proliferation and restenosis, which may not be reduced by TiNOX-coating.

In-stent restenosis of innominate artery with critical stenosis of right internal carotid artery

International Nuclear Information System (INIS)

Hussain, S.; Raza, A.; Ahmed, W.

2011-01-01

A lady with aortitis syndrome developed in-stent restenosis (ISR) of the innominate artery stent and critical stenosis of right internal carotid artery. The therapeutic challenge was gaining access to the carotid vessel, after treating the innominate artery ISR and all the while using distal protection to circumvent potential cerebral embolism. Percutaneous transluminal angioplasty (PTA) with or without stenting is a safe therapeutic option for re-vascularization of the supra aortic vessels. In the event of re-stenosis, re-treatment with PTA and stenting is safe. Ample evidence-base exists now for carotid artery stenting (CAS) in preference to carotid endarterectomy in patients with stenotic lesions of the carotid vessels. (author)

When stenting in renal artery stenosis? Update on pathophysiology of ischemic nephropathy and management strategies

Directory of Open Access Journals (Sweden)

Alessandro Zuccalà

2013-11-01

Full Text Available In recent years, decisions taken on the optimal management of patients with renal artery stenosis have triggered off controversy and debate among clinicians dealing with renovascular disease. The main reason underlying this ongoing controversy may be the heterogeneity of the clinical entities that are normally associated with the umbrella definition of renal artery stenosis. Indeed a causal link between the stenosis and its clinical consequences (i.e. hypertension, renal failure can often demonstrated in some entities, such as fibromuscular dysplasia, truncal stenosis or arterial stenosis in the transplanted kidney, which can be defined as pure renal artery stenosis. On the contrary, the entity generally called ostial stenosis is a disease of the abdominal aorta where it encroaches the ostium of the renal artery at the end of a long process involving the entire vascular tree. Patients affected by ostial stenosis also suffer from generalized atherosclerosis, and kidney damage is often caused by the atherosclerotic environment with the stenosis acting as an innocent bystander. This may account for the low rate of renal function recovery in subjects with ostial stenosis. In our view, keeping the different entities separate along with a careful understanding of the mechanisms underpinning renal damage, particularly the intrarenal activation of the renin angiotensin system which in turn induces renal inflammation and oxidative stress, may enable clinicians to make the right decisions in regard to revascularization.

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

Thirty-day outcomes of direct carotid artery stenting with cerebral protection in high-risk patients

International Nuclear Information System (INIS)

Veselka, J.; Cerna, D.; Zimolova, P.; Blasko, P.; Fiedler, J.; Hajek, P.; Maly, M.; Zemanek, D.; Duchonova, R.

2007-01-01

Implantation of a carotid artery stent after predilation is a standard approach in the endovascular treatment of carotid artery stenoses. Stenting without predilation may be an alternative approach in a certain subset of patients. The present prospective, single-center registry was designed to evaluate the feasibility and safety of direct carotid artery stenting (DCAS) in high-risk patients. Symptomatic patients with stenosis >50% and asymptomatic patients with stenosis >70% were eligible for enrolment. Criteria for high-risk patients included: need or history of open heart surgery, history of myocardial infarction, multivessel coronary artery disease, left ventricular dysfunction (ejection fraction ≤40%), severe pulmonary or renal disease, significant contralateral carotid disease, previous endarterectomy, and age ≥80 years. All procedures were performed using a filter protection device. Patients underwent complete clinical examination before and after DCAS and at 30-day follow-up. A total of 83 consecutive patients (45 males, 68±9 years, 33% symptomatic) underwent 100 procedures and 103 stents were deployed successfully. The technical success rate of stenting was 100%. Predilation of carotid stenosis was necessary in 1 (1%) procedure. Carotid-artery stenoses before and after DCAS were 80±9% and 7±9%, respectively. The median fluoroscopic time for DCAS was 7 min. The overall rate of in-hospital major adverse cerebrovascular events (death, stroke, myocardial infarction) was 5% (2 minor strokes, 3 transient attacks). There was 1 (1%) minor stroke within the 30-day follow-up. DCAS is feasible and can be performed with an acceptable risk in high-risk patients. (author)

Stent-induced flow disturbances in the ipsilateral external carotid artery following internal carotid artery stenting: a temporary cause of jaw claudication.

Science.gov (United States)

Giurgea, Georgiana-Aura; Haumer, Markus; Mlekusch, Irene; Sabeti-Sandor, Schila; Dick, Petra; Schillinger, Martin; Minar, Erich; Mlekusch, Wolfgang

2017-07-01

We hypothesize that stenting of the internal carotid artery can immediately impede blood flow to the external carotid artery by either plaque shift or stent coverage of the ostium, and thereby cause ischemic symptoms like ipsilateral jaw claudication. Thirty-three patients with high-grade asymptomatic stenosis of the internal carotid artery who underwent endovascular treatment were examined by ultrasound of the external carotid artery and performed an exercise test by chewing chewing gum synchronously to an electronic metronome for 3 min. Tests were performed before, the day after, and 1 week after the stenting procedure. Claudication time was defined as the timespan until occurrence of pain of the masseter muscle and/or chewing dyssynchrony to the metronome for more than 15 s. Ten patients with an isolated, atherosclerotic stenosis of the external carotid artery served as controls. A significantly reduced claudication time (in seconds) was recorded in patients who underwent carotid artery stenting compared to baseline values; median 89 (interquartile range, IQR, 57 to 124) vs. median 180 (IQR 153 to 180; p external carotid artery into faster or slower as 200 cm/sec, the effect was even accentuated. Stenting values showed improvement 1 week after but did not return to baseline levels. No respective changes were found in controls. Stenting of the internal carotid artery lead to ipsilateral flow deterioration at the external carotid artery resulting in temporary jaw claudication. This impairment attenuated over the time and was significantly reduced after 1 week.

Stent Design Affects Femoropopliteal Artery Deformation.

Science.gov (United States)

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

2018-03-23

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

Stent Graft in Managing Juxta-Renal Aortoiliac Occlusion

International Nuclear Information System (INIS)

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

2003-01-01

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

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

International Nuclear Information System (INIS)

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

2005-01-01

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

BILATERAL DUPLICATION OF RENAL ARTERIES

OpenAIRE

Prajkta A Thete; Mehera Bhoir; M.V.Ambiye

2014-01-01

Routine dissection of a male cadaver revealed the presence of bilateral double renal arteries. On the right side the accessory renal artery originated from the abdominal aorta just above the main renal artery. On the left side the accessory renal artery originated from the abdominal aorta about 1 cm above the main renal artery. Knowledge of the variations of renal vascular anatomy has importance in exploration and treatment of renal trauma, renal transplantation, renal artery embolization, su...

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

International Nuclear Information System (INIS)

Goltz, J.P.; Kickuth, R.; Bastuerk, P.; Hoppe, H.; Triller, J.

2011-01-01

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.)

An argument for the use of multiple segment stents in curved arteries.

Science.gov (United States)

Kasiri, Saeid; Kelly, Daniel J

2011-08-01

Stenting of curved arteries is generally perceived to be more challenging than straight vessels. Conceptually implanting multiple shorter stents rather than a single longer stent into such a curved artery represents a promising concept, but little is known about the impact of such an approach. The objective of this study is to evaluate the effectiveness of using a multiple segment stent rather than a single long stent to dilate a curved artery using the finite element method. A double segment stent (DSS) and a single segment stent (SSS) were modeled. The stents were compared when expanded into a model of a curved artery. The model predicts that the DSS provides higher flexibility, more conformity, and lower recoil in comparison to the SSS. The volume of arterial tissue experiencing high levels of stress due to stent implantation is also reduced for the DSS. It is suggested that a multiple segment stenting system is a potential solution to the problem of higher rates of in-stent restenosis in curved arteries and mechanically challenging environments.

Bilateral renal artery variation

OpenAIRE

Üçerler, Hülya; Üzüm, Yusuf; İkiz, Z. Aslı Aktan

2014-01-01

Each kidney is supplied by a single renal artery, although renal artery variations are common. Variations of the renal arteryhave become important with the increasing number of renal transplantations. Numerous studies describe variations in renalartery anatomy. Especially the left renal artery is among the most critical arterial variations, because it is the referred side forresecting the donor kidney. During routine dissection in a formalin fixed male cadaver, we have found a bilateral renal...

Ex vivo repair of renal artery aneurysm associated with surgical treatment of abdominal aortic aneurysm

Directory of Open Access Journals (Sweden)

Kostić Dušan M.

2004-01-01

shorter arteries was implanted into the long artery, and another one into PTFE graft. After 30 minutes of explanation, autotransplantation of the kidney into the right iliac fossa was performed. The right renal vein was implanted into the inferior vein cava, and PTFE graft into the right limb of Dacron graft. Immediately following the completion of both anastomoses, large volume of urine was evident. Finally, ureteneocystostomy was performed with previous insertion of double "J" catheter. In the immediate postoperative period, renal function was restored to normal, while postoperative angiography revealed all patent grafts. DISCUSSION The most common causes of renal artery aneurysms are arteriosclerosis, as in our case, and fibro-muscular dysplasia. Very often, renal artery aneurysms are asymptomatic and discovered only during angiography in patients with aneurysmal and occlusive aortic disease. Other cases include: arterial hypertension, groin pain and acute or chronic renal failure. Due to relatively small number of evaluated cases, the risk of aneurysmal rupture is not known. According to some authors, the overall rupture rate of renal artery aneurysm is 5%, however, the rupture risk becomes higher in young pregnant woman. Several standard surgical procedures are available for the repair of renal artery aneurysms. These include saphenous vein angioplasty, bypass grafting, as well as ex vivo reconstruction with reimplantation or autotransplantation. Furthermore, interventional embolization therapy, as well as endovascular treatment with ePTFE covered stent, or autologous vein-coverage stent graft, have been also reported to be successful. CONCLUSION The major indications for surgical treatment of renal artery aneurysms are to eliminate the source of thromboembolism which leads to fixed renal hypertension and kidney failure, as well as prevention of aneurysmal rupture.

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

Science.gov (United States)

Lettau, Michael; Bendszus, Martin; Hähnel, Stefan

2013-06-01

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

A Renal Perforating Artery Mistaken for Arterial Bleeding after Percutaneous Renal Biopsy: A Case Report

International Nuclear Information System (INIS)

Kim, Ye Lim; Lee, Chang Hee; Kim, Kyeong Ah; Park, Cheol Min

2009-01-01

Perirenal hematoma after a renal biopsy is a common complication that usually resolves spontaneously, but this rarely requires transfusions or surgical/radiological intervention. We report here on a case of a renal perforating artery that was mistaken for renal arterial bleeding in a 53-year-old woman who was complicated with perirenal hematoma after undergoing a percutaneous renal biopsy. On the color and pulsed wave Doppler ultrasonography, linear blood flow was seen in the perirenal hematoma, which extended perpendicularly from the renal parenchyma into the perirenal space, and this linear blood flow exhibited an arterial pulse wave. On CT angiography, the renal perforating artery was demonstrated as a curvilinear vessel coursing tangentially to the renal margin and we decided that it was a pseudolesion caused by the renal perforating artery. A renal perforating artery may be mistaken for renal arterial bleeding after a percutaneous renal biopsy. A renal perforating artery and arterial bleeding can be differentiated by the location and shape seen on a color Doppler examination and the pulse waves characteristics

A Renal Perforating Artery Mistaken for Arterial Bleeding after Percutaneous Renal Biopsy: A Case Report

Energy Technology Data Exchange (ETDEWEB)

Kim, Ye Lim; Lee, Chang Hee; Kim, Kyeong Ah; Park, Cheol Min [Korea University College of Medicine, Seoul (Korea, Republic of)

2009-12-15

Perirenal hematoma after a renal biopsy is a common complication that usually resolves spontaneously, but this rarely requires transfusions or surgical/radiological intervention. We report here on a case of a renal perforating artery that was mistaken for renal arterial bleeding in a 53-year-old woman who was complicated with perirenal hematoma after undergoing a percutaneous renal biopsy. On the color and pulsed wave Doppler ultrasonography, linear blood flow was seen in the perirenal hematoma, which extended perpendicularly from the renal parenchyma into the perirenal space, and this linear blood flow exhibited an arterial pulse wave. On CT angiography, the renal perforating artery was demonstrated as a curvilinear vessel coursing tangentially to the renal margin and we decided that it was a pseudolesion caused by the renal perforating artery. A renal perforating artery may be mistaken for renal arterial bleeding after a percutaneous renal biopsy. A renal perforating artery and arterial bleeding can be differentiated by the location and shape seen on a color Doppler examination and the pulse waves characteristics

Metallic stent for the treatment of iliac arterial stenosis

Energy Technology Data Exchange (ETDEWEB)

Park, Jae Hyung; Chung, Jin Wook; Han, Joon Koo; Suh, Chul Soo; Yoo, Jae Wook; Han, Man Chung [Seoul National University College of Medicine, Seoul (Korea, Republic of); Song, Chi Sung [Seoul City Boramae Hospital, Seoul (Korea, Republic of)

1993-07-15

In order to study the clinical efficacy of the metallic stent of the treatment of iliac arterial stenosis, the clinical and arteriographic findings of the 8 patients were retrospectively reviewed. All 8 patients were males with an age of 51 to 79. The Fontaine class for the functional status of lower extremities was II in 4 patients, III in 3 patents and IV in 1 patient. Self expandable Gianturco stent was inserted of in 7 iliac arteries and balloon expandable Palmaz stent was inserted in 2 iliac arteries in the 8 patients. The indications for the metallic stent application were localized dissection with significant residual stenosis in 6 sites, recoiling due to calcification in one case and eccentricity of the stenosislesionin 2 sites. The deployment of the metallic stent was successful in all the cases to maintain the patency of iliac arteries with residual stenosis less than 30%. The Fontaine class was improved to 1 in 6 patients, IIa in 1 patient and IIb in another one. During the follow up period of 3 to 14 month, none except one developed recurrence of the symptom. On the basis of our experience, we believe that metallic stent is safe and effective for the treatment of iliac arterial stenosis. However, we think that it is a complementary measure to the percutaneous transluminal angioplasty. The comparative study between different types of metallic stent and the long term effect should be investigated further.

Angioplasty and stent placement - carotid artery - discharge

Science.gov (United States)

... medlineplus.gov/ency/patientinstructions/000235.htm Angioplasty and stent placement - carotid artery - discharge To use the sharing ... the hospital. You may have also had a stent (a tiny wire mesh tube) placed in the ...

Hepatic artery stent-grafts for the emergency treatment of acute bleeding

Energy Technology Data Exchange (ETDEWEB)

Bellemann, Nadine, E-mail: nadine.bellemann@med.uni-heidelberg.de [Department of Diagnostic and Interventional Radiology, University Hospital Heidelberg, INF 110, 69120 Heidelberg (Germany); Sommer, Christof-Matthias; Mokry, Theresa; Kortes, Nikolas; Gnutzmann, Daniel; Gockner, Theresa; Schmitz, Anne [Department of Diagnostic and Interventional Radiology, University Hospital Heidelberg, INF 110, 69120 Heidelberg (Germany); Weitz, Jürgen [Department of Surgery, University Hospital Heidelberg, INF 110, 69120 Heidelberg (Germany); Department for Visceral, Thoracic and Vascular Surgery at the University Hospital, Technical University Dresden (Germany); Kauczor, Hans-Ulrich; Radeleff, Boris; Stampfl, Ulrike [Department of Diagnostic and Interventional Radiology, University Hospital Heidelberg, INF 110, 69120 Heidelberg (Germany)

2014-10-15

Highlights: • We report our experiences with stent-grafts for the treatment of acute hemorrhage from the hepatic artery or the stump of the gastroduodenal artery. • The technical success of stent-graft implantation was 88%. • The bleeding ceased immediately after stent-graft implantation in 88%. • The complication rate was 21%. - Abstract: Purpose: We evaluated the technical success and clinical efficacy of stent-graft implantation for the emergency management of acute hepatic artery bleeding. Methods: Between January 2010 and July 2013, 24 patients with hemorrhage from the hepatic artery were scheduled for emergency implantation of balloon expandable stent-grafts. The primary study endpoints were technical and clinical success, which were defined as successful stent-graft implantation with sealing of the bleeding site at the end of the procedure, and cessation of clinical signs of hemorrhage. The secondary study endpoints were complications during the procedure or at follow-up and 30-day mortality rate. Results: In 23 patients, hemorrhage occurred after surgery, and in one patient hemorrhage occurred after trauma. Eight patients had sentinel bleeding. In most patients (n = 16), one stent-graft was implanted. In six patients, two overlapping stent-grafts were implanted. The stent-grafts had a target diameter between 4 mm and 7 mm. Overall technical success was 88%. The bleeding ceased after stent-graft implantation in 21 patients (88%). The mean follow-up was 137 ± 383 days. In two patients, re-bleeding from the hepatic artery occurred during follow-up after 4 and 29 days, respectively, which could be successfully treated by endovascular therapy. The complication rate was 21% (minor complication rate 4%, major complication rate 17%). The 30-day mortality rate was 21%. Conclusions: Implantation of stent-grafts in the hepatic artery is an effective emergency therapy and has a good technical success rate for patients with acute arterial hemorrhage.

COVERED STENTS IN IATROGENIC CORONARY ARTERY FISTULA; A CASE REPORT

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Masoud Poormoghaddas

2010-11-01

Full Text Available Abstract    BACKGROUND: Coronary artery fistula is an abnormal communication between a coronary artery and a cardiac chamber or major cardiac vessels, mostly congenital but some of them are acquired as a consequence of coronary artery perforation.    CASE PRESENTATION: We report a case of cavity spilling coronary artery perforation during percutaneous coronary intervention 7 years ago. Because of continuing symptoms and risk of developing heart failure and pulmonary hypertension we were ought to treat this iatrogenically formed coronary artery fistula. We used stent graft implantation to treat it with acceptable results.    CONCLUSION: Beside their application as a rescue for acute coronary artery perforations, stent grafts can be used with acceptable results in iatrogenically acquired coronary artery coronary artery fistula      Keywords: Coronary artery perforation, Coronary artery fistula, Stent graft.

Primary stent placement for recanalization of iliac artery occlusions: Using a self-expanding spiral stent

International Nuclear Information System (INIS)

Kim, Jae-Kyu; Kim, Yun-Hyeon; Chung, Sang-Yeung; Kang, Heoung-Keun

1999-01-01

Purpose: To report the clinical results for recanalizations of an occluded iliac artery by a self-expanding spiral stent.Methods: We attempted to recanalize 36 iliac artery occlusions in 34 patients [33 men, 1 woman, aged 51-75 years (average 61.6 years)]. The average lesion length was 6.92 cm (range 1-14 cm). The patients's chief complaints were intermittent claudication and resting pain. Fontaine classification was assigned before and after the procedure. Technical and clinical success were also analyzed.Results: Forty-five stents were successfully deployed in 34 patients. All 36 lesions (13 in the external iliac artery, 12 in the common iliac artery, and 11 in both) were patently recanalized on angiography. The follow-up period ranged from 6 months to 36 months (mean 11.9 months). Fourteen stents (39%) with incomplete expansion were dilated with a balloon catheter. Good technical (100%) and clinical (94%) results were obtained. The only complication was one hematoma at the puncture site. Reocclusions were noted in two lesions (5%) at 1 week and 15 months, respectively.Conclusion: A self-expanding spiral stent is a safe and effective device for recanalization of an iliac artery occlusion as the primary stent without any previous intervention.

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

Energy Technology Data Exchange (ETDEWEB)

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

2009-08-15

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

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

International Nuclear Information System (INIS)

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

2003-01-01

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

Bilateral triple renal arteries

International Nuclear Information System (INIS)

Pestemalci, Turan; Yildiz, Yusuf Zeki; Yildirim, Mehmet; Mavi, Ayfer; Gumusburun, Erdem

2009-01-01

Knowledge of the variations of the renal artery has grown in importance with increasing numbers of renal transplants, vascular reconstructions and various surgical and radio logic techniques being performed in recent years. We report the presence of bilateral triple renal arteries, discovered on routine dissection of a male cadaver. On the right side, one additional renal artery originated from the abdominal aorta (distributed to superior pole of the kidney) and one other originated from the right common iliac artery (distributed to lower pole of the kidney). On the left side, both additional renal arteries originated from the abdominal aorta. Our observation has been compared with variations described in the literature and their clinical importance has been emphasized. (author)

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

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Utku Şenol

2013-03-01

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

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

Science.gov (United States)

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

2018-04-01

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

Hemodynamic Measurements for the Selection of Patients With Renal Artery Stenosis: A Systematic Review.

Science.gov (United States)

van Brussel, Peter M; van de Hoef, Tim P; de Winter, Robbert J; Vogt, Liffert; van den Born, Bert-Jan

2017-05-22

Interventions targeting renal artery stenoses have been shown to lower blood pressure and preserve renal function. In recent studies, the efficacy of catheter-based percutaneous transluminal renal angioplasty with stent placement has been called into question. In the identification of functional coronary lesions, hyperemic measurements have earned a place in daily practice for clinical decision making, allowing discrimination between solitary coronary lesions and diffuse microvascular disease. Next to differences in clinical characteristics, the selection of renal arteries suitable for intervention is currently on the basis of anatomic grading of the stenosis by angiography rather than functional assessment under hyperemia. It is conceivable that, like the coronary circulation, functional measurements may better predict therapeutic efficacy of percutaneous transluminal renal angioplasty with stent placement. In this systematic review, the authors evaluate the available clinical evidence on the optimal hyperemic agents to induce intrarenal hyperemia, their association with anatomic grading, and their predictive value for treatment effects. In addition, the potential value of combined pressure and flow measurements to discriminate macrovascular from microvascular disease is discussed. Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Flow Velocities After Carotid Artery Stenting: Impact of Stent Design. A Fluid Dynamics Study in a Carotid Artery Model with Laser Doppler Anemometry

International Nuclear Information System (INIS)

Greil, Oliver; Kleinschmidt, Thomas; Weiss, Wolfgang; Wolf, Oliver; Heider, Peter; Schaffner, Silvio; Gianotti, Marc; Schmid, Thomas; Liepsch, Dieter; Berger, Hermann

2005-01-01

Purpose. To study the influence of a newly developed membrane stent design on flow patterns in a physiologic carotid artery model. Methods. Three different stents were positioned in silicone models of the carotid artery: a stainless steel stent (Wall-stent), a nitinol stent (SelfX), and a nitinol stent with a semipermeable membrane (MembraX). To increase the contact area of the membrane with the vessel wall, another MembranX model was modified at the outflow tract. The membrane consists of a biocompatible silicone-polyurethane copolymer (Elast-Eon) with a pore size of 100 μm. All stents were deployed across the bifurcation and the external carotid artery origin. Flow velocity measurements were performed with laser Doppler anemometry (LDA), using pulsatile flow conditions (Re = 220; flow 0.39 l/min; flow rate ratio ICA:ECA = 70:30) in hemodynamically relevant cross-sections. The hemodynamic changes were analyzed by comparing velocity fluctuations of corresponding flow profiles. Results. The flow rate ratio ICA:ECA shifted significantly from 70/30 to 73.9/26.1 in the MembraX and remained nearly unchanged in the SelfX and Wallstent. There were no changes in the flow patterns at the inflow proximal to the stents. In the stent no relevant changes were found in the SelfX. In the Wallstent the separation zone shifted from the orifice of the ICA to the distal end of the stent. Four millimeters distal to the SelfX and the Wallstent the flow profile returned to normal. In the MembraX an increase in the central slipstreams was found with creation of a flow separation distal to the stent. With a modification of the membrane this flow separation vanished. In the ECA flow disturbances were seen at the inner wall distal to the stent struts in the SelfX and the Wallstent. With the MembraX a calming of flow could be observed in the ECA with a slight loss of flow volume. Conclusions. Stent placement across the carotid artery bifurcation induces alterations of the physiologic flow

Renal artery stenosis

International Nuclear Information System (INIS)

Desberg, A.; Paushter, D.M.; Lammert, G.K.; Hale, J.; Troy, R.; Novic, A.; Nally, J. Jr.

1989-01-01

Renal artery disease is a potentially correctable cause of hypertension. Previous studies have suggested the utility of duplex sonography in accurately detecting and grading the severity of renal artery stenosis. The purpose of this paper is to evaluate color flow Doppler for this use. Forty-three kidneys were examined by color-flow Doppler and conventional duplex sampling in patients with suspected renovascular hypertension or those undergoing aortography for unrelated reasons. Doppler tracings were obtained from the renal arteries and aorta with calculation of the renal aortic ratio (RAR) and resistive index (RI). Results of Doppler sampling with color flow guidance were compared with aortograms in a blinded fashion

Transpedal approach for iliac artery stenting: A pilot study

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Zachariah, Jips J., E-mail: jzachariah@chpnet.org [Mount Sinai Beth Israel Hospital, New York, NY (Israel); Ratcliffe, Justin A.; Ruisi, Michael; Puma, Joseph [Mount Sinai Beth Israel Hospital, New York, NY (Israel); Bertrand, Olivier [Quebec Heart and Lung Institute, Quebec (Canada); Kwan, Tak [Mount Sinai Beth Israel Hospital, New York, NY (Israel)

2016-12-15

Objective: To demonstrate the safety and feasibility of the transpedal approach as an alternate arterial access site for iliac artery intervention. Background: The common femoral artery is the traditional access site for the endovascular treatment of iliac artery stenoses. However, this approach is associated with complication rates as high as 2%, including retroperitoneal bleeding which carries high patient morbidity and mortality. Furthermore, the standard femoral approach is associated with longer recovery times and longer time to ambulation which are important considerations especially when performing procedures in an ambulatory setting. Methods: Twelve patients were prospectively followed after treatment for symptomatic iliac artery stenosis via transpedal access. Under ultrasound guidance, one of the pedal arteries was visualized and accessed, and stenting of the iliac arteries were performed as per protocol. The patient was monitored immediately post procedure and clinical follow up was performed at one week and one month later. Results: The average age of the patients was 71 years old. 58% were male. Most patients had Rutherford class III symptoms. Successful stent placement was achieved in all 12 patients via transpedal access. No conversion to femoral access was required. No complications immediately post procedure nor at any time period during follow up were noted. Lower extremity arterial duplex at one month showed patent stents and patent pedal access site vessels in all patients. Conclusion: Transpedal arterial access may be a safe and feasible approach for iliac artery stenting. Given the possible benefits of avoiding femoral artery access, larger studies should be conducted directly comparing the different approaches.

Treatment of Intra- and Extracranial Arterial Dissections Using Stents and Embolization

International Nuclear Information System (INIS)

Joo, Jin Yang; Ahn, Jung Yong; Chung, Young Sun; Han, In Bo; Chung, Sang Sup; Yoon, Pyeong Ho; Kim, Sang Heum; Choi, Eun Wan

2005-01-01

Purpose. To evaluate the safety and efficacy of stent placement for extracranial and intracranial arterial dissections. Methods. Eighteen patients underwent endovascular treatment of carotid and vertebral dissections using intraluminal stent placement. Five patients with arterial dissection were treated, 2 using one insertion of a single stent and 3 using placement of two stents. Patients with a dissecting aneurysm were treated as follows: 7 patients with insertion of one stent, 4 with placement of two stents, and 2 by stent-assisted Guglielmi detachable coil embolization. In the 18 patients in whom stenting was attempted, the overall success in reaching the target lesion was 94.4%. Of the 17 patients treated with stents, stent release and positioning were considered optimal in 16 (94%) and suboptimal in one (6%). In patients who underwent a successful procedure, all parent arteries were preserved. There were no instances of postprocedural ischemic attacks, new neurologic deficits, or new minor or major strokes prior to patient discharge. In follow up, all patients were assessed, using the modified Rankin scale, as functionally improved or of stable clinical status. The reduction in dissection-induced stenosis or pseudoaneurysm, the patency rate obtained at follow-up, and the lack of strokes (ischemic or hemorrhagic) suggest that stent placement offers a viable alternative to complex surgical bypass or reconstructive procedures. The long-term efficacy and durability of stent placement for arterial dissection remain to be determined in a larger series

Interventional treatment of transplanted renal artery stenosis

International Nuclear Information System (INIS)

Zhang Zefu; Liang Huiming; Feng Gansheng; Zheng Chuansheng; Wu Hanpin; Zhou Guofeng

2008-01-01

Objective: To evaluate the treatment of transplanted renal artery stenosis (TRAS) by pereutaneous transluminal angioplasty (PTA)and stentplacement. Methods: The averange time from trans- plantation to the symptom occurrence of TRAS was 5.5 months (4-15 months)in 12 TRAS patients. All of them received the interventional therapy through femoral approach. Average BP, creatinine level and stenosis before and after the procedure were taken as the judgement standards. Results: PTA was performed with balloon (length 20-40 mm, diameter 5-7 mm)in 4 patients, stenting after PTA in 5, including 3 of direct stenting. Two cases (17%)occurred restenosis after PTA and restenting was undertaken. Three ases (25%)with restenosis after stentplacement were undergone PTA. One self-expandable stent and 9 balloon- dilatation stent were released in 10 eases. Stenosis significantly decreased from 65%-95% preoperatively to 15%-25% postoperatively, together with average BP decreased from 175/105 mmHg to 140/80 mmHg and creatinine level decreased from 475.5 μmol/L to 118.5 μmol/L. Among 12 cases included 4 healed, melioration (5), improvement (2), and inefficiency (1) during follow-up of 9 months (3-24 months). No complication occurred. Conclusion: The interventional therapy is effective and safe for TRAS with high rates of procedure success and efficacy. The proper selection of the adapted approach combined with PTA and stenting may effectively raise the long term efficacy for TRAS and success rate of the procedure. (authors)

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

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

2014-05-28

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

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

International Nuclear Information System (INIS)

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

2014-01-01

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

A rare complication after renal transplantation: Forgotten stent

Directory of Open Access Journals (Sweden)

Mustafa Karabıcak

2015-07-01

Full Text Available In renal transplantation surgery, double J stents (DJS are often used to reduce complications, protect the anastomosis between ureter and bladder, provide drainage in ureteral obstructions and enhance healing if there is an ureter injury. Urinary tract infections, hematuria and irritative voiding symptoms are the early complications of DJS. Migration, fragmantation, encrustation and rarely sepsis are among the late complications of DJS. In this report we describe a renal transplantation case whose DJS stent was forgotten because the patient did not attend the regular follow-up and noticed 5 years after surgery.

Antegrade jj stenting after percutaneous renal procedures: The 'pull and push' technique.

Science.gov (United States)

Ratkal, Jaideep M; Sharma, Elias

2015-06-01

A JJ stent is inserted antegradely after percutaneous renal procedures like percutaneous nephrolithotomy (PCNL) for renal calculus disease, and for endopyelotomy for pelvi-ureteric junction obstruction. We describe a technique for antegrade stent insertion after PCNL.

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

International Nuclear Information System (INIS)

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

2013-01-01

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

Stent grafting of acute hepatic artery bleeding following pancreatic head resection

International Nuclear Information System (INIS)

Stoupis, Christoforos; Ludwig, Karin; Triller, Juergen; Inderbitzin, Daniel; Do, Dai-Do

2007-01-01

The purpose of this study was to report the potential of hepatic artery stent grafting in cases of acute hemorrhage of the gastroduodenal artery stump following pancreatic head resection. Five consecutive male patients were treated because of acute, life-threatening massive bleeding. Instead of re-operation, emergency angiography, with the potential of endovascular treatment, was performed. Because of bleeding from the hepatic artery, a stent graft (with the over-the-wire or monorail technique) was implanted to control the hemmorhage by preserving patency of the artery. The outcome was evaluated. In all cases, the hepatic artery stent grafting was successfully performed, and the bleeding was immediately stopped. Clinically, immediately after the procedure, there was an obvious improvement in the general patient condition. There were no immediate procedure-related complications. Completion angiography (n=5) demonstrated control of the hemorrhage and patency of the hepatic artery and the stent graft. Although all patients recovered hemodynamically, three individuals died 2 to 10 days after the procedure. The remaining two patients survived, without the need for re-operation. Transluminal stent graft placement in the hepatic artery is a safe and technically feasible solution to control life-threatening bleeding of the gastroduodenal artery stump. (orig.)

53. Bilateral ductal stenting for nonconfluent pulmonary arteries in a newborn

Directory of Open Access Journals (Sweden)

K. Al Dhahri

2016-07-01

Full Text Available Bilateral PDA dependent pulmonary circulation with right and left pulmonary artery discontinuity is very rare. Limited data available for bilateral PDA stenting. Bilateral PDA stenting in nonconfluent pulmonary arteries is challenging procedure but can be considered as an option in the management of complex conditions like this. 12 days old Preterm (36 weeks gestation male baby with birth weight of 2.6 kg developed respiratory distress with severe cyanosis and desaturation upto 50%. Baby was intubated and started on Prostaglandin 0.05 mic/kg/mt. His saturation improved to 80%. Echocardiogram showed complex cyanotic heart disease, Situs ambiguous, dextrocardia, complete unbalanced AV septal defect, pulmonary atresia , nonconfluent small branch pulmonary arteries supplied by the bilateral patent ductus arteriosus (PDA from right aortic arch and all four pulmonary veins form a confluence and drain into superior vena cava(SVC through vertical vein with no obstruction. Baby was taken up for PDA stenting. descending aortogram showed right aortic arch with vertical tortuous duct to right pulmonary artery (RPA and another short duct with acute angle from left subclavian artery to left pulmonary artery (LPA . Both ducti stented with coronary stents. Vertical vein angiogram showed both lungs drain to a confluence and then to SVC via ascending vertical vein with no obstruction. After stenting lung perfusion improved and the baby was stable and maintained 80% saturation on room air. Bilateral PDA dependent pulmonary circulation with right and left pulmonary artery discontinuity is very rare. Our case is unique with Heterotaxy, TAPVC, Dextrocardia and double ducti. Eventhough bilateral ductal stenting is technically challenging it is successful through femoral artery approach.

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.

Percutaneous treatment of transplant renal artery stenosis in children.

Science.gov (United States)

Repetto, Horacio A; Rodríguez-Rilo, Laila; Mendaro, Esteban; Basso, Laura; Galvez, Hugo; Morrone, Gabriela; Vazquez, Luis A

2004-12-01

Percutaneous treatment of renal artery stenosis (RAS) is an accepted procedure and numerous reports have been published. However, experience with its use in RAS in the transplanted kidney in children is scarce. Since 1994 we have diagnosed RAS in seven children with the use of Doppler ultrasonography (US), confirming it with percutaneous angiography (PAG). In six of the seven patients percutaneous transluminal angioplasty (PTA) was performed. In one patient a metallic stent was placed due to the extension of the arterial lesion, and a second stent was placed in another child when a re-stenosis was diagnosed 1 month after the PTA. All patients presented with hypertension (de novo or 30% increase over previous values). After ruling out acute rejection, calcineurin inhibitor toxicity, and urinary obstruction, US was performed and, when an increase in arterial flux velocity was registered, PAG was also performed. Six children showed an increase in serum creatinine (Cr) and proteinuria. Blood pressure decreased after the procedure and Cr returned to previous levels in all children. One of the grafts was lost due to chronic transplant rejection 7 years later. The other children have a functioning kidney. Although this is a small group of patients, the consistently good results and the lack of reported experience prompted us to communicate our preliminary observation.

Subintimal stent placement in patients with long segment occlusion of the iliac artery

Energy Technology Data Exchange (ETDEWEB)

Yu, Ho Jung; Kim, Young Hwan; Kim, Si Hyung; Ko, Sung Min; Choi, Jin Soo; Lee, Hyun Jin; Kim, Hyung Tae; Jo, Won Hyun [Dongsan Medical Center, Keimyung University College of Medicine, Daegu (Korea, Republic of); Kim, Yong Joo [Andong General Hospital, Andong (Korea, Republic of)

2008-01-15

We evaluated the technical feasibility and clinical efficacy of subintimal stent placement for long segment occlusion of the iliac artery. From March 2003 to February 2007, subintimal stent placement for long segment occlusion of the iliac artery of 24 limbs in 22 patients was analyzed retrospectively. Endovascular access was performed via the ipsilateral femoral artery in 7 cases, via the contralateral femoral artery in 6 cases, via both femoral arteries in 10 cases and via the brachial artery in one case. The SAFARI (subintimal arterial flossing with antegrade-retrograde intervention) technique using a microcatheter was performed to recannalize iliac artery occlusion in three cases. Medical records were reviewed for the collection of follow-up data. The stent patency rate was analyzed by use of the Kaplan-Meier method. Subintimal stent placement was technically successful in 23 of 24 procedures (95.8%). The mean ankle-brachial index (ABI) increased form 0.26 to 0.82. The Fontaine classification was improved after stent placement in all patients. Major complications occurred in four procedures: three distal embolizations and one arterial rupture. All of the complications were successfully treated by endovascular intervention. The primary stent patency rates at 6-months, 1-, 2-and 3-years were 95%, 88%, 88% and 88%, respectively. Subintimal stent placement is a safe and effective treatment for long segment occlusion of the iliac artery.

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

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

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

Science.gov (United States)

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

2002-03-01

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

Renal Transplant Ureteral Stenosis: Treatment by Self-Expanding Metallic Stent

International Nuclear Information System (INIS)

Cantasdemir, Murat; Kantarci, Fatih; Numan, Furuzan; Mihmanli, Ismail; Kalender, Betul

2003-01-01

We report the use of a metallic stent in a transplant ureteral stenosis. A 28-year-old man with chronic renal failure due to chronic pyelonephritis, who received a living-donor renal transplant, presented with transplant ureteral stenosis. The stenosis was unresponsive to balloon dilation and was treated by antegrade placement of a self-expanding Memotherm stent. The stentedureter stayed patent for 3 years. It may be reasonable to treat post-transplant ureteral stenosis resistant to balloon dilation with self-expanding metallic stents. However, long-term follow-up is required to evaluate the efficacy of this treatment

Angioplasty and stent placement in the treatment of radiation-induced arterial injury

International Nuclear Information System (INIS)

Liu Pengcheng; Pierre, P.; Philippe, O.; Danial, C.; Jean-Paul, B.; Cyril, B.; Jean-Pierre, C.; Denis, K.; Helve, R.; Francis, J.

1999-01-01

Objective: Evaluation of therapeutic efficacy and longterm patency of angioplasty and stent for the treatment of radiation induced arterial disease. Methods: PTA was attempted in 18 arterial lesions following irradiation in 14 patients. Thirteen stents were placed in 8 patients to treat occlusion (n = 3), aneurysm (n = 1), residual stenosis (n =2), multiple stenoses (n = 1), and delayed restenosis after previous balloon angioplasty (n = 1). The stents were readily visualized and patency of the stent and the target artery determined with Doppler US and (or) CT in all patients. Results: Interventional procedure was successful in 14 patients of which 8 underwent stent placement for their arterial lesions. Eleven of these patients demonstrated primary patency with relief of clinical symptoms with a mean follow-up of 2 years (range, 8 months -60 months). Clinical improvement was noted for the other patients. Eleven patients underwent PTA once or twice. One patient had PTA four times and three stents were installed, two of which were in the area of the aortic bifurcation, and one in the celiac trunk. another patient also had PTA four times and two stents were placed in the superior mesenteric artery. A stent was implanted in one patient because of PTA induced dissection and occlusion, and the arterial lesion was considered to be cured clinically after a follow-up of 5 years. Conclusions: The results suggested that PTA with single or multiple techniques may be effective immediately in the treatment of arterial lesions caused by radiation and can be considered the first therapeutic option in these cases

Flow Characteristics Near to Stent Strut Configurations on Femoropopliteal Artery

Science.gov (United States)

Paisal, Muhammad Sufyan Amir; Fadhil Syed Adnan, Syed; Taib, Ishkrizat; Ismail, Al Emran; Kamil Abdullah, Mohammad; Nordin, Normayati; Seri, Suzairin Md; Darlis, Nofrizalidris

2017-08-01

Femoropopiteal artery stenting is a common procedure suggested by medical expert especially for patient who is diagnosed with severe stenosis. Many researchers reported that the growth of stenosis is significantly related to the geometry of stent strut configuration. The different shapes of stent geometry are presenting the different flow pattern and re-circulation in stented femoropopliteal artery. The blood flow characteristics near to the stent geometry are predicted for the possibility of thrombosis and atherosclerosis to be formed as well as increase the growth of stenosis. Thus, this study aims to determine the flow characteristic near to stent strut configuration based on different hemodynamic parameters. Three dimensional models of stent and simplified femoropopliteal artery are modelled using computer aided design (CAD) software. Three different models of stent shapes; hexagon, circle and rectangle are simulated using computational fluid dynamic (CFD) method. Then, parametric study is implemented to predict the performance of stent due to hemodynamic differences. The hemodynamic parameters considered are pressure, velocity, low wall shear stress (WSSlow) and wall shear stress (WSS). From the observation, flow re-circulation has been formed for all simulated stent models which the proximal region shown the severe vortices. However, rectangular shape of stent strut (Type P3) shows the lowest WSSlow and the highest WSS between the range of 4 dyne/cm2 and 70 dyne/cm2. Stent Type P3 also shows the best hemodynamic stent performance as compare to others. In conclusion, Type P3 has a favourable result in hemodynamic stent performance that predicted less probability of thrombosis and atherosclerosis to be formed as well as reduces the growth of restenosis.

Renal Branch Artery Stenosis

DEFF Research Database (Denmark)

Andersson, Zarah; Thisted, Ebbe; Andersen, Ulrik Bjørn

2017-01-01

Renovascular hypertension is a common cause of pediatric hypertension. In the fraction of cases that are unrelated to syndromes such as neurofibromatosis, patients with a solitary stenosis on a branch of the renal artery are common and can be diagnostically challenging. Imaging techniques...... that perform well in the diagnosis of main renal artery stenosis may fall short when it comes to branch artery stenosis. We report 2 cases that illustrate these difficulties and show that a branch artery stenosis may be overlooked even by the gold standard method, renal angiography....

Endovascular Repair of Acute Symptomatic Pararenal Aortic Aneurysm With Three Chimney and One Periscope Graft for Complete Visceral Artery Revascularization

International Nuclear Information System (INIS)

Brechtel, Klaus; Ketelsen, Dominik; Endisch, Andrea; Heller, Stephan; Heuschmid, Martin; Stock, Ulrich A.; Kalender, Guenay

2012-01-01

PurposeTo describe a modified endovascular technique for complete revascularization of visceral and renal arteries in symptomatic pararenal aortic aneurysm (PRAA).TechniqueArterial access was surgically established in both common femoral arteries (CFAs) and the left subclavian artery (LSA). Revascularization of the left renal artery, the celiac trunk, and the superior mesenteric artery was performed through one single sheath via the LSA. Suitable covered stents were put in the aortic branches but not deployed. The right renal artery was accessed over the left CFA. Due to the longitudinal extension of the presented aneurysm two stent-grafts were introduced via the right CFA. After deploying the aortic stent-grafts, all covered stents in the side branches were deployed consecutively with a minimum overlap of 5 mm over the cranial and caudal stent-graft edges. Simultaneous ballooning was performed to fully expand all stent-grafts and warranty patency. Conclusion: This is the first report in the literature of chimney grafting in PRAA for complete revascularization of visceral and renal branches by using more than two covered stents introduced from one side through one single sheath. However this technique is modified, it should be used only in bailout situations when branched stent-grafts are not available and/or surgery is not suitable.

Imaging of coronary artery stents using multislice computed tomography: in vitro evaluation

International Nuclear Information System (INIS)

Maintz, David; Juergens, Kai-Uwe; Heindel, Walter; Fischbach, Roman; Wichter, Thomas; Grude, Matthias

2003-01-01

The aim of this study was to evaluate imaging features of different coronary artery stents during multislice CT Angiography (MSCTA). Nineteen stents made of varying material (steel, nitinol, tantalum) and of varying stent design were implanted in plastic tubes with an inner diameter of 3 mm to simulate a coronary artery. The tubes were filled with iodinated contrast material diluted to 200 Hounsfield units (HU), closed at both ends and positioned in a plastic container filled with oil (-70 HU). The MSCT scans were obtained perpendicular to the stent axes (detector collimation 4 x 1 mm, table feed 2 mm/rotation, 300 mAs, 120 kV). Axial images and multiplanar reformations were evaluated regarding artifact size, lumen visibility, and intraluminal attenuation values. Artifacts characterized by artifactual thickening of the stent struts leading to apparent reduction in the lumen diameter and increased intraluminal attenuation values were observed in all cases. The stent lumen was totally obscured in the Wiktor stent, the Wallgraft stent, and the Nir Royal stent. Partial residual of the stent lumen could be visualized in all other utilized stent products (artificial lumen reductions ranged from 62% in the V-Flex stent to 94% in the Bx Velocity stent). Parts of the stent lumen can be visualized in most coronary artery stents; however, detectability of in-stent stenoses remains to be evaluated for each stent type. (orig.)

Stent angioplasty for the treatment of symptomatic stenosis of middle cerebral artery

International Nuclear Information System (INIS)

Lu Huisheng; Niu Huiming; Chao Yuanxiang; Li Xiaoning; Wu Dingfeng; Zhang Chenhong; Yang Jie; Zhang Liang

2010-01-01

Objective: To investigate the safety and feasibility of endovascular stent angioplasty in treating symptomatic stenosis of middle cerebral artery. Methods: Endovascular angioplasty with coronary stents was performed in 27 patients with symptomatic stenosis of middle cerebral artery. The clinical results were reviewed and analyzed. Results: Of the total 27 patients, successful placement of the coronary stents was achieved in 24. Angiography immediately after the procedure showed that the stenotic degree of the diseased artery was markedly decreased from preoperative (80 ± 19)% to postoperative (8 ±4)%, the improvement was very obvious. Percutaneous transcatheter angioplasty had to be employed in two cases because of the failure of stent placement. A mean follow-up period of 18 months was carried out. During the following up period no transient cerebral ischemia attack occurred in 25 patients and no newly-developed cerebral infarction in region fed by the responsible vessels occurred either.Re-irrigation cerebral hemorrhage was seen in one patient, which occurred three hours after the placement of the stent. In one case the placed stent fell off and immigrated into the siphon of internal carotid artery, and the displaced stent was took out later with a catching apparatus. In another case re-stenosis occurred six months after the stenting. Conclusion: Percutaneous endovascular stent angioplasty is a safe and effective treatment for symptomatic stenosis of middle cerebral artery, although its long-term results need to be further evaluated. (authors)

Primary stenting as emergency therapy in acute basilar artery occlusion

International Nuclear Information System (INIS)

Spreer, Joachim; Arnold, Sebastian; Klisch, Joachim; Schumacher, Martin; Els, Thomas; Hetzel, Andreas; Huppertz, Hans-Juergen; Oehm, Eckhardt

2002-01-01

In three patients with acute occlusion of the basilar artery intra-arterial fibrinolysis resulted in only partial recanalization and revealed severe stenosis as the underlying cause. Application of micro-stents without previous dilatation resulted in vessel re-opening. Two patients had an excellent clinical outcome. One patient died 10 days after the stroke due to brainstem infarction. Emergency primary stent application may improve the outcome in acute basilar artery occlusion, if intra-arterial thrombolysis fails to re-establish a sufficient flow. (orig.)

Treatment of carotid artery aneurysms with covered stents; Aneurysmabehandlung der Arteria carotis interna mit gecoverten Stents

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Rohr, A.; Alfke, K.; Doerner, L.; Jansen, O. [UKSH Kiel (Germany). Neurochirurgie Neuroradiologie; Bartsch, T.; Stingele, R. [UKSH Kiel (Germany). Neurologie

2007-10-15

Purpose: Evaluation of the use of covered stents in treating pseudoaneurysms of the cervical and intracranial/extradural carotid artery and determination of the periprocedural and short- to mid-term complication rate. Materials and Methods: 8 patients with 9 spontaneous dissecting aneurysms of the cervical carotid artery - 5 of which were symptomatic - plus one patient with ofthalmoplegia due to an aneurysm of the cavernous carotid artery were studied. While the latter was treated with a PTFE-covered balloon-mounted stainless steel stent (Jostent/Graftmaster), a self-expanding PTFE-covered Nitonol Stent (Symbiot) was used in all other cases. Intervention was performed with local anesthesia. Aspirin and Clopidogrel were both used as antiplatelet drugs. Clinical signs and symptoms and vascular imaging with DS, MR, CT angiography and ultrasound were recorded during patient follow-up, with a mean follow-up period of 14.6 months (4 - 30). Results: We were able to treat 8 out of 10 aneurysms (80 %) using covered stents. The aneurysms were immediately occluded and the associated stenoses of the parent vessel were eliminated. No clinically relevant complications occurred during the procedure or in the follow-up interval. In two cases, elongation of the carotid artery prevented the stent from being positioned over the aneurysm neck. These cases were shown to be stable with the use of antiplatelet drugs. Conclusion: Covered stents can be used in the treatment of pseudoaneurysms of the carotid artery as an alternative to long-term antithrombotic medication or surgery. In our study treatment was effective (80 %) and free of complications in the short- and mid-term follow-up. Possible indications, technique and the use of imaging modalities for patient follow-up are discussed. (orig.)

[Successful correction with stent-graft of coronary artery rupture after angioplasty].

Science.gov (United States)

Demin, V V

2003-01-01

Rupture and perforation of coronary arteries complicate in average 0.5% of radiosurgical coronary interventions and often are accompanied by serious consequences and high mortality. According to-type of coronary perforation different methods of correction are used, ranging from conservative measures to urgent cardiosurgical interventions. Coronary stent-grafts with 'sandwich' type of construction ore composed from two metal stents and PTFE layer between them. Development of such stents enabled effective radioguided endovascular repair of coronary ruptures. The paper presents the first Russian experience of stout-graft implantation for coronary artery rupture occurred during direct stenting of proximal anterior descending artery and balloon angioplasty in distal segment. The rupture occurred probably because of wall fragility between affected segment and muscular bridge. Stent-graft JoStent 16 mm in length connected with 3-mm balloon was implanted with subsequent complete restitution of blood flow, resolution of pain syndrome and ECG normalization. Echocardiography in operative theatre and one day after surgery showed no intrapericardial fluid. Stent-graft devices for urgent implantation in cases of coronary rupture must be included into obligatory equipment of radiosurgical facilities.

The use of coronary stent in hepatic artery stenosis after orthotopic liver transplantation

International Nuclear Information System (INIS)

Huang Mingsheng; Shan Hong; Jiang Zaibo; Li Zhengran; Zhu Kangshun; Guan Shouhai; Qian Jiesheng; Chen Guihua; Lu Minqiang; Yang Yang

2006-01-01

Purpose: This retrospective study was undertaken to evaluate the effectiveness of coronary stent placement in hepatic artery stenosis after orthotopic liver transplantation (OLT). Materials and methods: Of 430 consecutive adult orthotopic liver transplant recipients between November 2003 and September 2005, 17 had hepatic artery stenosis (HAS). Fourteen of them underwent coronary stent placement in the HAS. The technical results, complications, hepatic artery patency and clinical outcome were reviewed. Results: Technical and immediate success was 100%. After a mean follow-up of 159.4 days (range, 9-375 days), all patients obtained patent hepatic arteries except 2 patients occurred hepatic artery restenoses at 26 and 45 days after stent placement, respectively. Kaplan-Meier curve of patency showed cumulated stent patency at 3, 6, and 12 months of 78%, 58% and 45%, respectively. During the follow-up, 8 patients survived, 5 died of septic multiple-organ failure, 1 received retransplantation because of refractory biliary infection. Hepatic artery dissection induced by a guiding catheter occurred in one patient and was successfully treated with a coronary stent. Conclusion: Hepatic artery stenosis after OLT can be successfully treated with coronary stent placement with low complication rate and an acceptable 1-year hepatic artery patency rate

Nitinol Stents in the Femoropopliteal Artery: A Mechanical Perspective on Material, Design, and Performance

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Maleckis, Kaspars; Anttila, Eric; Aylward, Paul; Poulson, William; Desyatova, Anastasia; MacTaggart, Jason; Kamenskiy, Alexey

2018-01-01

Endovascular stenting has matured into a commonly used treatment for peripheral arterial disease (PAD) due to its minimally invasive nature and associated reductions in short-termmorbidity and mortality. The mechanical properties of the superelastic Nitinol alloy have played a major role in the explosion of peripheral artery stenting, with modern stents demonstrating reasonable resilience and durability. Yet in the superficial femoral and popliteal arteries, even the newest generation Nitinol stents continue to demonstrate clinical outcomes that leave significant room for improvement. Restenosis and progression of native arterial disease often lead to recurrence of symptoms and reinterventions that increase morbidity and health care expenditures. One of the main factors thought to be associated with stent failure in the femoropopliteal artery (FPA) is the unique and highly dynamic mechanical environment of the lower limb. Clinical and experimental data demonstrate that the FPA undergoes significant deformations with limb flexion. It is hypothesized that the inability of many existing stent designs to conform to these deformations likely plays a role in reconstruction failure, as repetitive movements of the leg and thigh combine with mechanical mismatch between the artery and the stent and result in mechanical damage to both the artery and the stent. In this review we will identify challenges and provide a mechanical perspective of FPA stenting, and then discuss current research directions with promise to provide a better understanding of Nitinol, specific features of stent design, and improved characterization of the biomechanical environment of the FPA to facilitate development of better stents for patients with PAD. PMID:29470746

Nitinol Stents in the Femoropopliteal Artery: A Mechanical Perspective on Material, Design, and Performance.

Science.gov (United States)

Maleckis, Kaspars; Anttila, Eric; Aylward, Paul; Poulson, William; Desyatova, Anastasia; MacTaggart, Jason; Kamenskiy, Alexey

2018-05-01

Endovascular stenting has matured into a commonly used treatment for peripheral arterial disease (PAD) due to its minimally invasive nature and associated reductions in short-term morbidity and mortality. The mechanical properties of the superelastic Nitinol alloy have played a major role in the explosion of peripheral artery stenting, with modern stents demonstrating reasonable resilience and durability. Yet in the superficial femoral and popliteal arteries, even the newest generation Nitinol stents continue to demonstrate clinical outcomes that leave significant room for improvement. Restenosis and progression of native arterial disease often lead to recurrence of symptoms and reinterventions that increase morbidity and health care expenditures. One of the main factors thought to be associated with stent failure in the femoropopliteal artery (FPA) is the unique and highly dynamic mechanical environment of the lower limb. Clinical and experimental data demonstrate that the FPA undergoes significant deformations with limb flexion. It is hypothesized that the inability of many existing stent designs to conform to these deformations likely plays a role in reconstruction failure, as repetitive movements of the leg and thigh combine with mechanical mismatch between the artery and the stent and result in mechanical damage to both the artery and the stent. In this review we will identify challenges and provide a mechanical perspective of FPA stenting, and then discuss current research directions with promise to provide a better understanding of Nitinol, specific features of stent design, and improved characterization of the biomechanical environment of the FPA to facilitate development of better stents for patients with PAD.

Testicular artery arising from an aberrant right renal artery | Suluba ...

African Journals Online (AJOL)

This case report we discovered the rare variation of the origin of the right testicular artery arising from the right aberrant renal artery with double renal artery irrigating both left and right kidneys. These variations in the testicular arteries and renal arteries have implication to surgical procedures such as orchidopexy repair for ...

Antegrade jj stenting after percutaneous renal procedures: The ‘pull and push’ technique

Science.gov (United States)

Ratkal, Jaideep M.; Sharma, Elias

2014-01-01

A JJ stent is inserted antegradely after percutaneous renal procedures like percutaneous nephrolithotomy (PCNL) for renal calculus disease, and for endopyelotomy for pelvi-ureteric junction obstruction. We describe a technique for antegrade stent insertion after PCNL. PMID:26413327

Treatment of splenic artery aneurysm with double overlapping bare stents: case report

International Nuclear Information System (INIS)

Kwak, Hyo Sung; Han, Young Min; Jin, Gong Yong

2004-01-01

The traditional treatment of splenic artery aneurysm (SAA) is generally surgery and/or transcatheter arterial embolization, but recently, the treatment of SAA using a stent graft has been reported. However, the acute angle of the celiac axis, as well as the tortuous path of the splenic artery makes the use of stent graft difficult for treatment of aneurysma. We report here a case of SAA treated with the technique of double overlapping metallic stents

Endovascular stent-assisted thrombolysis in acute occlusive carotid artery dissection

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Mourand, Isabelle [Hopital Gui de Chauliac, Department of Neurology, CHU Montpellier, Montpellier, Cedex 5 (France); Hopital Gui de Chauliac, Department of Neurology, Service de Neurologie, Montpellier, Cedex 5 (France); Brunel, Herve; Vendrell, Jean-Francois; Bonafe, Alain [Hopital Gui de Chauliac, Department of Neuroradiology, CHU Montpellier, Montpellier, Cedex 5 (France); Thouvenot, Eric [Hopital Gui de Chauliac, Department of Neurology, CHU Montpellier, Montpellier, Cedex 5 (France)

2010-02-15

Internal carotid artery dissection with tandem internal carotid and middle cerebral artery occlusion may be responsible for large cerebral infarction that carries a general poor prognosis. Recanalization of internal carotid artery (ICA) dissection by stent-assisted thrombolysis has been recently proposed. We report two cases of acute symptomatic ICA dissection with tandem occlusion successfully treated with emergent endovascular stent-assisted thrombolysis using new self-expandable intracranial stents. A 37-year-old woman and a 59-year-old man were admitted in our hospital after acute severe symptoms of right-hemispheric stroke with National Institutes of Health Stroke Scale (NIHSS) scores of 15 and 18, respectively. In both cases, magnetic resonance angiography showed tandem occlusion and angiography confirmed tandem occlusion with ICA dissection. An extensive mismatch region was diagnosed by Perfusion-diffusion MRI of the brain within 3 h after symptoms onset. Treatment was initiated 4 h after symptom onset by implantation of self-expandable intracranial stents into the dissected ICA and administration of intra-arterial recombinant tissue plasminogen activator. Recanalization of the ICA and middle cerebral artery (MCA) was accomplished within 6 h after symptoms onset. In both cases, no periprocedural complication was observed and follow-up CT scan showed only a mild brain infarct in the MCA territory. After, respectively, 12 and 10 months follow-up, patients had a favorable outcome with NIHSS 0 and mRS {<=}1. Endovascular stent-assisted thrombolysis appears to be a promising treatment in tandem occlusion due to ICA dissection. Our work underline the potential use of self-expandable intracranial stents in symptomatic acute ICA dissection. (orig.)

Blood Pressure Response to Main Renal Artery and Combined Main Renal Artery Plus Branch Renal Denervation in Patients With Resistant Hypertension.

Science.gov (United States)

Fengler, Karl; Ewen, Sebastian; Höllriegel, Robert; Rommel, Karl-Philipp; Kulenthiran, Saaraaken; Lauder, Lucas; Cremers, Bodo; Schuler, Gerhard; Linke, Axel; Böhm, Michael; Mahfoud, Felix; Lurz, Philipp

2017-08-10

Single-electrode ablation of the main renal artery for renal sympathetic denervation showed mixed blood pressure (BP)-lowering effects. Further improvement of the technique seems crucial to optimize effectiveness of the procedure. Because sympathetic nerve fibers are closer to the lumen in the distal part of the renal artery, treatment of the distal main artery and its branches has been shown to reduce variability in treatment effects in preclinical studies and a recent randomized trial. Whether this optimized technique improves clinical outcomes remains uncertain. We report a 2-center experience of main renal artery and combined main renal artery plus branches renal denervation in patients with resistant hypertension using a multielectrode catheter. Twenty-five patients with therapy-resistant hypertension underwent renal sympathetic denervation with combined main renal artery and renal branch ablation and were compared to matched controls undergoing an ablation of the main renal artery only. BP change was assessed by ambulatory measurement at baseline and after 3 months. At baseline, BP was balanced between the groups. After 3 months, BP changed significantly in the combined ablation group (systolic/diastolic 24-hour mean and daytime mean BP -8.5±9.8/-7.0±10.7 and -9.4±9.8/-7.1±13.5 mm Hg, P renal artery and branches appears to improve BP-lowering efficacy and should be further investigated. © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

The current role of vascular stents.

Science.gov (United States)

Busquet, J

1993-09-01

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

Time-dependent 3D simulations of the hemodynamics in a stented coronary artery

International Nuclear Information System (INIS)

Faik, Isam; Mongrain, Rosaire; Leask, Richard L; Rodes-Cabau, Josep; Larose, Eric; Bertrand, Olivier

2007-01-01

Stenting is becoming the major interventional cardiology procedure worldwide. However restenosis remains a major limitation to the effectiveness of stents. Alterations to the local hemodynamics in the stented segment of the artery could be a potential factor in the development of in-stent restenosis. The characterization of wall shear stress and of blood flow patterns in a stented artery is therefore necessary for a good understanding of the role of hemodynamics in the development of in-stent restenosis. We have used a time-dependent 3D numerical model of a stented coronary artery to study the characteristics of the blood flow and the shear stress distribution. Our results show that the presence of the stent produces significant secondary flow that is limited to an annulus in the near wall region. Low shear stress zones were localized in the vicinity of the struts while the tips of the struts exhibited high values of shear stress. These results support the hypothesis that local hemodynamics may affect the development of in-stent restenosis and could influence the choice of stent geometries for future stent designs

Renal Artery Stenosis (RAS) Case study

International Nuclear Information System (INIS)

Zaater, M.K.

2012-01-01

Renal Artery Stenosis (RAS), is one of the causes of secondary hypertension; there are many causes of renal artery stenosis, as atherosclerosis of the renal artery which account for 90% of cases of RAS; fibromuscular dysplasia accounts for 10% of RAS. Various causes of thrombophilia either due congenital causes or acquired causes and can lead to RAS. Our patient was presented by acute attack of epistaxis and hypertension. Angiography of the Renal Arteries,are showed no sign of renal artery stenosis. However, the right kidney showed upper pole infarction, and the left kidney showed evidence of functional lower pole renal artery stenosis, although there is no anatomical stenosis detected in angiography. Work up for the cause of thrombophilia did not help in the diagnosis, which may be due to an undiscovered cause of thrombophilia

Anatomic Patterns of Renal Arterial Sympathetic Innervation: New Aspects for Renal Denervation.

Science.gov (United States)

Imnadze, Guram; Balzer, Stefan; Meyer, Baerbel; Neumann, Joerg; Krech, Rainer Horst; Thale, Joachim; Franz, Norbert; Warnecke, Henning; Awad, Khaled; Hayek, Salim S; Devireddy, Chandan

2016-12-01

Initial studies of catheter-based renal arterial sympathetic denervation to lower blood pressure in resistant hypertensive patients renewed interest in the sympathetic nervous system's role in the pathogenesis of hypertension. However, the SYMPLICITY HTN-3 study failed to meet its prespecified blood pressure lowering efficacy endpoint. To date, only a limited number of studies have described the microanatomy of renal nerves, of which, only two involve humans. Renal arteries were harvested from 15 cadavers from the Klinikum Osnabruck and Schuchtermann Klinik, Bad Rothenfelde. Each artery was divided longitudinally in equal thirds (proximal, middle, and distal), with each section then divided into equal superior, inferior, anterior, and posterior quadrants, which were then stained. Segments containing no renal nerves were given a score value = 0, 1-2 nerves with diameter 4 nerves or nerve diameter ≥600 µm a score = 3. A total of 22 renal arteries (9 right-sided, 13 left-sided) were suitable for examination. Overall, 691 sections of 5 mm thickness were prepared. Right renal arteries had significantly higher mean innervation grade (1.56 ± 0.85) compared to left renal arteries (1.09 ± 0.87) (P renal artery has significantly higher innervation scores than the left. The anterior and superior quadrants of the renal arteries scored higher in innervation than the posterior and inferior quadrants did. The distal third of the renal arteries are more innervated than the more proximal segments. These findings warrant further evaluation of the spatial innervation patterns of the renal artery in order to understand how it may enhance catheter-based renal arterial denervation procedural strategy and outcomes. The SYMPLICITY HTN-3 study dealt a blow to the idea of the catheter-based renal arterial sympathetic denervation. We investigated the location and patterns of periarterial renal nerves in cadaveric human renal arteries. To quantify the density of the

Experimental research of covered stent implanted in canine hepatic artery

International Nuclear Information System (INIS)

Zhou Bing; Liu Linxiang; Li Minghua; Wang Yongli; Cheng Yongde

2007-01-01

Objective: To evaluate the feasibility of success rate of implantation, post-procedure stenosis rate, apposition ability and endothelialization level, etc. for implantation with balloon-expandable covered stent in canine hepatic artery. Methods: 8 adult canines were implanted with balloon-expendable stents covered by expandable poly Teflon ester membrane (e-PTFEM). Follow-up DSA was performed immediately, 2, 4 and 12 wk after the procedure. The canines were sacrificed for histopathologic examination and statistical analysis with correlation of implantation manenvor and angiographic manifestations. Results: 8 cases were all implanted with the covered stents in proper hepatic artery/right hepatic artery successfully; showing good apposition ability and non-opacification of the separated branches. 2 cases showed intraluminal obvious stenosis( > 50%)of the stent at 2 weeks follow-up, so did 3 cases at 12 weeks follow-up, and the total stenosis rate was 37.5% and 5 cases manifested full endothelialization (3 different locations of the sample all manifested full endothelialization), 3 cased manifested partial endothelialization (at least 1 location of the sample didn't show full endothelialization), and the two terminal parts were easier to get endothelialization than the central part. Before and after the stent implantation, hepatic function of all cases didn't demonstrate any obvious changes. Conclusions: Balloon-expandable covered stent can be implanted in canine hepatic artery. successfully, with good apposition ability, full endothelialization, and no influence on hepatic function. (authors)

Endovascular stent-assisted thrombolysis in acute occlusive carotid artery dissection

International Nuclear Information System (INIS)

Mourand, Isabelle; Brunel, Herve; Vendrell, Jean-Francois; Bonafe, Alain; Thouvenot, Eric

2010-01-01

Internal carotid artery dissection with tandem internal carotid and middle cerebral artery occlusion may be responsible for large cerebral infarction that carries a general poor prognosis. Recanalization of internal carotid artery (ICA) dissection by stent-assisted thrombolysis has been recently proposed. We report two cases of acute symptomatic ICA dissection with tandem occlusion successfully treated with emergent endovascular stent-assisted thrombolysis using new self-expandable intracranial stents. A 37-year-old woman and a 59-year-old man were admitted in our hospital after acute severe symptoms of right-hemispheric stroke with National Institutes of Health Stroke Scale (NIHSS) scores of 15 and 18, respectively. In both cases, magnetic resonance angiography showed tandem occlusion and angiography confirmed tandem occlusion with ICA dissection. An extensive mismatch region was diagnosed by Perfusion-diffusion MRI of the brain within 3 h after symptoms onset. Treatment was initiated 4 h after symptom onset by implantation of self-expandable intracranial stents into the dissected ICA and administration of intra-arterial recombinant tissue plasminogen activator. Recanalization of the ICA and middle cerebral artery (MCA) was accomplished within 6 h after symptoms onset. In both cases, no periprocedural complication was observed and follow-up CT scan showed only a mild brain infarct in the MCA territory. After, respectively, 12 and 10 months follow-up, patients had a favorable outcome with NIHSS 0 and mRS ≤1. Endovascular stent-assisted thrombolysis appears to be a promising treatment in tandem occlusion due to ICA dissection. Our work underline the potential use of self-expandable intracranial stents in symptomatic acute ICA dissection. (orig.)

Factors that affect mass transport from drug eluting stents into the artery wall

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Walsh Michael T

2010-03-01

Full Text Available Abstract Coronary artery disease can be treated by implanting a stent into the blocked region of an artery, thus enabling blood perfusion to distal vessels. Minimally invasive procedures of this nature often result in damage to the arterial tissue culminating in the re-blocking of the vessel. In an effort to alleviate this phenomenon, known as restenosis, drug eluting stents were developed. They are similar in composition to a bare metal stent but encompass a coating with therapeutic agents designed to reduce the overly aggressive healing response that contributes to restenosis. There are many variables that can influence the effectiveness of these therapeutic drugs being transported from the stent coating to and within the artery wall, many of which have been analysed and documented by researchers. However, the physical deformation of the artery substructure due to stent expansion, and its influence on a drugs ability to diffuse evenly within the artery wall have been lacking in published work to date. The paper highlights previous approaches adopted by researchers and proposes the addition of porous artery wall deformation to increase model accuracy.

Mechanical Recanalization of Cerebral Artery Embolic Occlusion Using a Self-Expanding Stent: Experimental Analysis in Canine Model

International Nuclear Information System (INIS)

Choi, Jin Woo; Kim, Snag Joon; Lee, Deok Hee; Suh, Dae Chul

2011-01-01

To evaluate the feasibility of a self-expanding stent for acute embolic occlusion, and recanalization mechanism by histologic examination. Five mongrel dogs were used as study subjects. Each vertebral artery was occluded, and a self-expanding stent was used for recanalization. We evaluated the technical success rate for the placement of the stent to the targeted vessel, the recanalization rate, and residual stenosis. We obtained two specimens of the stented vertebral arteries for histologic evaluation. One dog died of an unknown cause during the induction of anesthesia. In two dogs, only one side of the vertebral artery was used, whereas both vertebral arteries were used in the remaining dogs. A total of six vertebral arteries were successfully occluded. The technical success rate for stenting without complication was 66.7%. The immediate recanalization rate after stenting was 100%. The residual stenosis was 35.6 ± 18.6%. On microscopic examination, the stent concentrically displaced the clot and the clot was captured between the stent mesh and arterial wall. Self-expanding stents were effective in revascularizing the cerebrovascular embolic occlusion. The self-expanding stent seemed to achieve recanalization by pushing the clot to the arterial wall and capturing the clot between the stent mesh and arterial wall.

Mechanical Recanalization of Cerebral Artery Embolic Occlusion Using a Self-Expanding Stent: Experimental Analysis in Canine Model

Energy Technology Data Exchange (ETDEWEB)

Choi, Jin Woo; Kim, Snag Joon; Lee, Deok Hee; Suh, Dae Chul [Dept. of Radiology and Research Institute of Radiology, Asan Medical Center, Ulsan University College of Medicine, Seoul (Korea, Republic of)

2011-07-15

To evaluate the feasibility of a self-expanding stent for acute embolic occlusion, and recanalization mechanism by histologic examination. Five mongrel dogs were used as study subjects. Each vertebral artery was occluded, and a self-expanding stent was used for recanalization. We evaluated the technical success rate for the placement of the stent to the targeted vessel, the recanalization rate, and residual stenosis. We obtained two specimens of the stented vertebral arteries for histologic evaluation. One dog died of an unknown cause during the induction of anesthesia. In two dogs, only one side of the vertebral artery was used, whereas both vertebral arteries were used in the remaining dogs. A total of six vertebral arteries were successfully occluded. The technical success rate for stenting without complication was 66.7%. The immediate recanalization rate after stenting was 100%. The residual stenosis was 35.6 {+-} 18.6%. On microscopic examination, the stent concentrically displaced the clot and the clot was captured between the stent mesh and arterial wall. Self-expanding stents were effective in revascularizing the cerebrovascular embolic occlusion. The self-expanding stent seemed to achieve recanalization by pushing the clot to the arterial wall and capturing the clot between the stent mesh and arterial wall.

[Anatomy character of renal artery and treatment of living-donor renal transplantation].

Science.gov (United States)

Zhang, Lei; Fei, Ji-guang; Chen, Li-zhong; Wang, Chang-xi; Deng, Su-xiong; Qiu, Jiang; Li, Jun; Chen, Guo-dong; Huang, Gang

2009-12-15

To study the anatomy characters of renal artery and the treatment of multiple arteries in living donor renal grafts. Records of 142 living donors were analyzed in our center. We analyzed the anatomic structure of renal arteries by DSA and CTA pre-transplantation. Thirty-one kidneys with multiple arteries were transplanted after reconstruction. Then clinical effects were compared between multiple-renal-arteries group (n=31) and single-renal-artery group (n=111). The incidence of multiple renal artery was 30.99%, and there was no difference between both sides (left kidney 22.54%, right kidney 22.13%). If the multiple artery occurred in left or right kidney, the incidence of the multiple artery occurred in the other side was 56.25% and 60.00%, respectively. The diameter of left main renal artery was more magnanimous (P=0.001) and the first branch was more closed to abdominal aorta (P=0.004). Operation time and warm/cool ischemia time were longer in the multiple-renal-arteries group. However, estimated blood loss, delayed graft function, acute rejection and flow rate of arcuate artery were similar in both groups, the same as serum creatinine and serum creatinine clearance rate on day 7, 1 month and 3 month post-operation. It was shown by repeated measures ANOVA that graft with multiple arteries didn't affect the tendency of renal function at early time post-operation. Comprehending the character of renal artery and accurate treatment of multiple artery anastomosis are critical for the effect of the living kidney transplantation.

Use of a wire extender during neuroprotected vertebral artery angioplasty and stenting.

Science.gov (United States)

Lesley, Walter S; Kumar, Ravi; Rangaswamy, Rajesh

2010-09-01

The off-label use of an extender wire during vertebral artery stenting and angioplasty with or with neuroprotection has not been previously reported. Retrospective, single-patient, technical report. After monorail balloon angioplasty was performed on a proximal left vertebral artery stenosis, the 190 cm long Accunet neuroprotection filter device was not long enough for delivery of an over-the-wire stent. After mating a 145 cm long, 0.014 inch extension wire to the filter device, a balloon-mounted Liberté stent was implanted with good angiographic and clinical results. The off-label use of an extender wire permits successful over-the-wire stenting on a monorail neuroprotection device for vertebral artery endosurgery.

Risk factors for in-stent restenosis of vertebral artery origin after stent implantation: a Meta-analysis

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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

Robot-Assisted Antegrade In-Situ Fenestrated Stent Grafting

International Nuclear Information System (INIS)

Riga, Celia V.; Bicknell, Colin D.; Wallace, Daniel; Hamady, Mohamad; Cheshire, Nicholas

2009-01-01

To determine the technical feasibility of a novel approach of in-situ fenestration of aortic stent grafts by using a remotely controlled robotic steerable catheter system in the porcine model. A 65-kg pig underwent robot-assisted bilateral antegrade in-situ renal fenestration of an abdominal aortic stent graft with subsequent successful deployment of a bare metal stent into the right renal artery. A 16-mm iliac extension covered stent served as the porcine aortic endograft. Under fluoroscopic guidance, the graft was punctured with a 20-G customized diathermy needle that was introduced and kept in place by the robotic arm. The needle was exchanged for a 4 x 20 mm cutting balloon before successful deployment of the renal stent. Robot-assisted antegrade in-situ fenestration is technically feasible in a large mammalian model. The robotic system enables precise manipulation, stable positioning, and minimum instrumentation of the aorta and its branches while minimizing radiation exposure.

Self-Expandable Stent Placement in Infrapopliteal Arteries After Unsuccessful Angioplasty Failure: One-Year Follow-up

International Nuclear Information System (INIS)

Peregrin, J. H.; Smirova, S.; Koznar, B.; Novotny, J.; Kovac, J.; Lastovickova, J.; Skibova, J.

2008-01-01

The purpose of this prospective study was to evaluate whether stent placement in infrapopliteal arteries is helpful in failed percutaneous transluminal angioplasty (PTA). Infrapopliteal PTA was performed in 70 arteries of 66 patients with chronic critical lower limb ischemia. The group comprised 55 males and 11 females, with an average age of 63.4 (range, 42-82) years. Diabetes mellitus was present in 92.4% of patients. Only the palpable anterior tibial and posterior tibial arteries were evaluated. Stents (Xpert stent; Abbot Vascular, Redwood City, CA, USA) were placed in 16 arteries where PTA was not successful (the failure was defined as residual stenosis >30% after PTA). In 54 arteries simple PTA was performed and was technically successful. Twenty-four nondilated arteries with no significant stenosis served as a comparison group. The 12-month patency rate was evaluated according to a combination of palpation and Doppler ultrasound. In all cases stent placement restored the flow in the artery immediately after unsuccessful PTA. Twelve-month follow-up showed a patency rate of 82% in the PTA group, 78% in the stent group, and 69% in the comparison group. We conclude that stent placement in the case of unsuccessful infrapopliteal PTA changed technical failure to success and restored flow in the dilated artery. At 12-month follow-up the patency rate of infrapopliteal arteries stented for PTA failure did not differ significantly either from nonstented arteries with an optimal PTA result or from a comparison group of nonintervened arteries.

Study on the effect of location of intracranial arterial stenosis on the safety of stenting

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Yu-jie SUN

2017-11-01

Full Text Available Objective To investigate the effect of location of intracranial arterial stenosis on the safety of intracranial stenting. Methods A total of 73 patients with symptomatic intracranial atherosclerotic stenosis (ICAS were divided into intracranial internal carotid artery (IICA, N = 18, middle cerebral artery (MCA-M1 segment (MCA-M1, N = 11, intracranial vertebral artery (IVA, N = 27 and basilar artery (BA, N = 17. All of them underwent intracranial stenting. The improvement of intracranial arterial stenosis, cerebrovascular complications including perforating events, artery dissection, in-stent thrombosis, distal stent arterial embolism and cerebral hyperperfusion, and neurological complications including transient ischemic attack (TIA, ischemic stroke and intracranial hemorrhage were recorded. Modified Rankin Scale (mRS was used to evaluate the prognosis 30 d after operation. Results A total of 73 stents were implanted in 73 patients (35 Apollo balloon-expandable stents and 38 Wingspan self-expandable stents. Among them, 10 cases (10/18 were treated with Apollo stents and 8 cases (8/18 with Wingspan stents in IICA group, 5 cases (5/11 were treated with Apollo stents and 6 cases (6/11 with Wingspan stents in MCA-M1 group, 16 cases (59.26%, 16/27 were treated with Apollo stents and 11 cases (40.74%, 11/27 with Wingspan stents in IVA group, and 4 cases (4/17 were treated with Apollo stents and 13 cases (13/17 with Wingspan stents in BA group. No significant difference was seen in stent type among 4 groups (χ2 = 7.422, P = 0.201. The stenosis rate of IICA group after treatment [(10.94 ± 1.99%] was significantly improved than before treatment [(90.89 ± 7.71%; t = 69.545, P = 0.000]. The stenosis rate of MCA-M1 group after treatment [(10.37 ± 2.14%] was significantly improved than before treatment [(87.64 ± 9.46%; t = 26.000, P = 0.000]. The stenosis rate of IVA group after treatment [(11.02 ± 1.99% ] was significantly improved than before

Current global status of carotid artery stent placement.

Science.gov (United States)

Wholey, M H; Wholey, M; Bergeron, P; Diethrich, E B; Henry, M; Laborde, J C; Mathias, K; Myla, S; Roubin, G S; Shawl, F; Theron, J G; Yadav, J S; Dorros, G; Guimaraens, J; Higashida, R; Kumar, V; Leon, M; Lim, M; Londero, H; Mesa, J; Ramee, S; Rodriguez, A; Rosenfield, K; Teitelbaum, G; Vozzi, C

1998-05-01

Our purpose was to review the current status of carotid artery stent placement throughout the world. Surveys were sent to major interventional centers in Europe, North and South America, and Asia. Information from peer-reviewed journals was also included and supplemented the survey. The survey asked various questions regarding the patients enrolled, procedure techniques, and results of carotid stenting, including complications and restenosis. Of the centers which were sent surveys, 24 responded. The total number of endovascular carotid stent procedures that have been performed worldwide to date included 2,048 cases, with a technical success of 98.6%. Complications that occurred during carotid stent placement or within a 30-day period following placement were recorded. Overall, there were 63 minor strokes, with a rate of occurrence of 3.08%. The total number of major strokes was 27, for a rate of 1.32%. There were 28 deaths within a 30-day postprocedure period, resulting in a mortality rate of 1.37%. Restenosis rates of carotid stenting have been 4.80% at 6 mo. Endovascular stent treatment of carotid artery atherosclerotic disease is growing as an alternative to vascular surgery, especially for patients that are at high risk for standard carotid endarterectomy. The periprocedural risks for major and minor strokes and death are generally acceptable at this early stage of development.

Randomized Comparison of Paclitaxel-Eluting Balloon and Stenting Versus Plain Balloon Plus Stenting Versus Directional Atherectomy for Femoral Artery Disease (ISAR-STATH).

Science.gov (United States)

Ott, Ilka; Cassese, Salvatore; Groha, Philipp; Steppich, Birgit; Hadamitzky, Martin; Ibrahim, Tareq; Kufner, Sebastian; Dewitz, Karl; Hiendlmayer, Regina; Laugwitz, Karl-Ludwig; Schunkert, Heribert; Kastrati, Adnan; Fusaro, Massimiliano

2017-06-06

Atherosclerosis in the superficial femoral artery is common in patients suffering from peripheral artery disease. Paclitaxel-eluting balloon (PEB) angioplasty, stenting, and directional atherectomy (DA) have provided new options for the treatment of superficial femoral artery disease; however, the comparative efficacy of these interventional strategies remains uncertain. One hundred and fifty-five patients with symptomatic peripheral artery disease due to de novo superficial femoral artery stenotic or occlusive lesions were randomized to treatment with plain balloon angioplasty (BA) followed by PEB angioplasty and stenting (n=48), BA and stenting (n=52), or DA with distal protection and bailout stenting (n=55). The primary end point of the study was percentage diameter stenosis after 6 months measured by angiography. Other end points included target lesion revascularization, thrombosis, ipsilateral amputation, binary restenosis, and all-cause mortality at 6 and 24 months. Baseline and lesion characteristics were comparable in all groups with a mean lesion length of 65.9±46.8 mm and 56% total occlusions. At 6 months angiography, the percent diameter stenosis was significantly lower in patients treated by PEB angioplasty and stenting (34±31%) as compared with BA angioplasty and stenting (56±29%, P =0.009) or DA (55±29%, P =0.007). Similarly, binary restenosis was significantly lower after treatment with PEB and stenting as compared with BA and stenting or DA. Clinical follow-up at 24 months revealed a lower risk for target lesion revascularization after PEB angioplasty and stenting as compared with BA and stenting or DA. We found no difference in terms of target lesion thrombosis and mortality among groups, and no patient underwent amputation. Treatment of de novo superficial femoral artery lesions with PEB angioplasty and stenting is superior to BA angioplasty and stenting or DA in terms of angiographic diameter stenosis at 6 months and target lesion

Usefulness of CT angiography after metallic stent implantation of the internal carotid artery

International Nuclear Information System (INIS)

Yoon, Man Won; Kim, Hyeon Chul; Kim, Jae Kyu; Seo, Jeong Jin; Jeong, Gwang Woo; Kang, Heoung Keun

1999-01-01

To evaluate the usefulness of CT angiography in patients with implantation of metallic stent for stenosed internal carotid artery. Seven patients with atherosclerotic stenosis of the internal carotid artery underwent metallic stent implantation. All were male and their ages ranged from 36 to 69 years. A total of seven stents were placed in the internal carotid artery in five patients and in the carotid bifurcation in two. Spiral CT scans were obtained and CT angiographic images were reconstructed using MPR or curved MPR techniques at a workstation. The interval between CT and conventional angiography did not exceed six days except in one patient, in whom it was 61days. CT and conventional angiography were compared for stent position with respect to the carotid bifurcation, stent deformation, intraluminal filling defect, and luminal caliber and outflow. Luminal patency of the implanted stent was measured according to NASCET(North American Symptomatic Carotid Endarterectomy Trial) criteria, and statistically processed (p>.05). The presence or absence of intrastent thrombus and vascular wall calcification was determined using axial source images. In all patients, CT angiographic findings matched those obtained by conventional angiography. Complications such as migration or deformation of an implanted stent, intraluminal filling defect, change of luminal caliber or outflow of implanted stent were not observed in any patient. In two studies in which Wilcoxon signed rank test was used, degree of stent expansion correlated closely(p=0.237). Axial source images showed that in no patient was an intrastent thrombus present, though in five, vascular wall calcification of internal carotid arteries outside the stent was noted. CT angiography is useful for the assessment of positional change, occlusion, and luminal patency of a stent-implanted internal carotid artery

The new technique of using the epigastric arteries in renal transplantation with multiple renal arteries

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Mohammad Ali Amirzargar

2013-01-01

Full Text Available The most common anatomic variant seen in the donor kidneys for renal transplantation is multiple renal arteries (MRA, which can cause an increased risk of complications. We describe the long-term outcomes of 16 years of experience in 76 kidney transplantations with MRAs. In a new reconstruction technique, we remove arterial clamps after anastomosing the donor to the recipient′s main renal vessels, which cause backflow from accessory arteries to prevent thrombosis. By this technique, we reduce the ischemic times as well as the operating times. Both in live or cadaver donor kidneys, lower polar arteries were anastomosed to the inferior epigastric artery and upper polar arteries were anastomosed to the superior epigastric arteries. Injection of Papaverine and ablation of sympathic nerves of these arteries dilate and prevent them from post-operative spasm. Follow-up DTPA renal scan in all patients showed good perfusion and function of the transplanted kidney, except two cases of polar arterial thrombosis. Mean creatinine levels during at least two years of follow-up remained acceptable. Patient and graft survival were excellent. No cases of ATN, hypertension, rejection and urologic complications were found. In conclusion, this technique can be safely and successfully utilized for renal transplantation with kidneys having MRAs, and may be associated with a lower complication rate and better graft function compared with the existing techniques.

Self-expanding nitinol stents for treatment of infragenicular arteries following unsuccessful balloon angioplasty

International Nuclear Information System (INIS)

Tepe, Gunnar; Heller, Stephan; Wiskirchen, Jakub; Fischmann, Arne; Claussen, Claus D.; Zeller, Thomas; Coerper, Stephan; Beckert, Stefan; Balletshofer, Bernd

2007-01-01

The feasibility of self-expanding nitinol stents for treatment of infragenicular arteries following unsuccessful balloon angioplasty was assessed. Options for lower limb percutaneous revascularization are limited, especially for complex vessel obstruction. Depending on the lesion and the experience of the interventionalist, the failure rate of balloon angioplasty (PTA) ranges between 10 and 40%. Until recently, no self-expanding stent for the use in the infragenicular arteries was available. This is the first report of the results for 18 consecutive patients who received 4F sheath compatible self-expanding nitinol stents following unsuccessful PTA or early restenosis. Twenty-four stents were implanted in 21 lesions for various indications residual stenosis >50% due to heavy calcification, flow-limiting dissection, occluding thrombus resistant to thrombolyis, thrombaspiration, and PTA, and early restenosis after previous PTA. Stent implantation was feasible in all cases. No complications occurred. After the stent implantation, all primarily unsuccessful interventions could be transformed into successful procedures with no residual stenosis >30% in any case. After 6 ± 2 months, two of the 18 patients died, and 14 of the 16 remaining patients improved clinically. At follow-up, the patency could be assessed in 14 stented arteries. Three stents were occluded, one stent showed some neointimal hyperplasia (50-70% restenosis), the remaining ten stents showed no restenosis (0-30%). The use of self-expanding nitinol stents in tibioperoneal and popliteal arteries is a safe and feasible option for the treatment of unsuccessful PTA. The 6-months patency is high. (orig.)

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

Science.gov (United States)

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

2013-01-01

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

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

Relationship between the Direction of Ophthalmic Artery Blood Flow and Ocular Microcirculation before and after Carotid Artery Stenting.

Science.gov (United States)

Ishii, Masashi; Hayashi, Morito; Yagi, Fumihiko; Sato, Kenichiro; Tomita, Goji; Iwabuchi, Satoshi

2016-01-01

When internal carotid artery stenosis is accompanied by ocular ischemic syndrome, intervention is recommended to prevent irreversible visual loss. In this study, we used laser speckle flowgraphy to measure the ocular microcirculation in the optic nerve head before and after carotid artery stenting (CAS) of 40 advanced internal carotid stenosis lesions from 37 patients. The aim was to investigate the relationship between ocular microcirculation and the direction of ophthalmic artery blood flow obtained by angiography. We found that there was a significant increase in blood flow after CAS ( P = 0.003). Peak systolic velocity as an indicator of the rate of stenosis was also significantly higher in the group with retrograde/undetected flow of the ophthalmic artery than in the group with antegrade flow ( P = 0.002). In all cases where retrograde flow of the ophthalmic artery was observed before stenting, the flow changed to antegrade after stenting. Through the use of laser speckle flowgraphy, this study found that CAS can improve ocular microcirculation. Furthermore, while patients displaying retrograde flow of the ophthalmic artery before stenting have a poor prognosis, CAS corrected the flow to antegrade, suggesting that visual loss can be prevented by improving the ocular microcirculation.

Renal artery pseudoaneurysm

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Luiz Inácio Roman

Full Text Available Abstract The renal artery pseudoaneurysm embody a rare vascular complication coming of percutaneous procedures, renal biopsy, nephrectomy, penetrating traumas and more rarely blunt traumas. The clinical can be vary according the patient, the haematuria is the symptom more commom. Is necessary a high level of clinical suspicion for your diagnosis, this can be elucidated by through complementary exams as the eco-color Doppler and the computed tomography scan (CT. This report is a case of a patient submitted a right percutaneous renal biopsy and that, after the procedure started with macroscopic haematuria, urinary tenesmus and hypogastric pain. The diagnosis of pseudoaneurysm was given after one week of evolution when the patient was hospitalized because gross haematuria, tachycardia, hypotension and hypochondrium pain. In the angiotomography revealed a focal dilation of the accessory right renal inferior polar artery, dilation of renal pelvis and all the ureteral course with presence hyperdenso material (clots inside the middle third of the ureter. The treatment for the majority of this cases are conservative, through arterial embolization, indicated for thouse of smaller dimensions in patients who are hemodynamically stable. However, it was decided by clinical treatment with aminocaproic acid 1 g, according to previous studies for therapy of haematuria. The patient received discharge without evidence of macroscopic haematuria and with normal renal ultrasound, following ambulatory care.

Management of Endovascular Aortic Aneurysm Complications via Retrograde Catheterization Through the Distal Stent-Graft Landing Zone.

Science.gov (United States)

Zhang, Xicheng; Sun, Yuan; Chen, Zhaolei; Jing, Yuanhu; Xu, Miao

2017-08-01

A retrograde technique through the gap between the distal stent landing zone and the iliac artery wall has been applied to treat type II endoleak after endovascular aortic aneurysm repair (EVAR). In this study, we tried to investigate its efficacy in the management of type III endoleak and intraoperative accidental events. We reported 2 complications of EVAR that were difficult to treat with conventional methods. One patient had a sustained type III endoleak after EVAR, and the right renal artery was accidentally sealed by a graft stent in the other patient during the operation. Both complications were managed by the retrograde technique from the distal stent landing zone. In the first case, the endoleak was easily embolized by the retrograde catheterization technique, and in the second case, a stent was implanted in the right renal artery using the retrograde technique to restore blood flow. In some EVAR cases, the technique of retrograde catheterization through the distal stent-graft landing zone is feasible, safe, and easy to perform.

Assessment of coronary artery stent patency by electron-beam CT

International Nuclear Information System (INIS)

Knollmann, Friedrich D.; Felix, Roland; Moeller, Joerg; Gebert, Axel; Bethge, Christian

2004-01-01

Following coronary angioplasty and stent implantation, restenosis remains common and its outcome difficult to predict. We set out to determine the diagnostic accuracy of electron-beam computed tomography (EBCT) for the non-invasive detection of stent obstruction. In a prospective, blinded investigation, we included 152 coronary artery segments in 117 patients treated with a stent implant. All segments were evaluated by a dynamic EBCT study that depicted contrast bolus passage distal to the stent and a CT angiographic study of the entire coronary arteries. It was found that delayed contrast enhancement in the distal segment correlated with angiographic stent obstruction (Spearman's rank correlation, P=0.008), while all other indicators of stent occlusion did not correlate with angiographic diagnosis. However, direct comparison of patients with obstruction of less vs. more than 75% of luminal diameter did not yield any statistically significant differences of distal enhancement delay, and for the detection of >90% occlusion, the sensitivity was 72% at a specificity of 60%. Although delayed contrast enhancement distal to the stent upon EBCT did correlate with angiographical obstruction, the correlation did not suffice to appear clinically satisfactory. (orig.)

Assessment of coronary artery stent patency by electron-beam CT

Energy Technology Data Exchange (ETDEWEB)

Knollmann, Friedrich D.; Felix, Roland [Department of Radiology, Charite, Campus Virchow-Klinikum, Humboldt-University, Augustenburger Platz 1, 13353, Berlin (Germany); Moeller, Joerg; Gebert, Axel; Bethge, Christian [Department of Cardiology, Juedisches Krankenhaus, Berlin (Germany)

2004-08-01

Following coronary angioplasty and stent implantation, restenosis remains common and its outcome difficult to predict. We set out to determine the diagnostic accuracy of electron-beam computed tomography (EBCT) for the non-invasive detection of stent obstruction. In a prospective, blinded investigation, we included 152 coronary artery segments in 117 patients treated with a stent implant. All segments were evaluated by a dynamic EBCT study that depicted contrast bolus passage distal to the stent and a CT angiographic study of the entire coronary arteries. It was found that delayed contrast enhancement in the distal segment correlated with angiographic stent obstruction (Spearman's rank correlation, P=0.008), while all other indicators of stent occlusion did not correlate with angiographic diagnosis. However, direct comparison of patients with obstruction of less vs. more than 75% of luminal diameter did not yield any statistically significant differences of distal enhancement delay, and for the detection of >90% occlusion, the sensitivity was 72% at a specificity of 60%. Although delayed contrast enhancement distal to the stent upon EBCT did correlate with angiographical obstruction, the correlation did not suffice to appear clinically satisfactory. (orig.)

Does the presence of accessory renal arteries affect the efficacy of renal denervation?

Science.gov (United States)

Id, Dani; Kaltenbach, Benjamin; Bertog, Stefan C; Hornung, Marius; Hofmann, Ilona; Vaskelyte, Laura; Sievert, Horst

2013-10-01

This study sought to assess the efficacy of catheter-based renal sympathetic denervation in patients with accessory renal arteries and to compare the blood pressure (BP)-lowering effect with that observed in patients with bilateral single renal arteries after renal denervation. Catheter-based renal sympathetic denervation causes significant BP reductions in patients with resistant hypertension. Seventy-four patients were included in this study. Patients were assigned to 2 main groups: a bilateral single renal arteries group I (n = 54) and an accessory renal arteries group II (n = 20). Group II consisted of 9 patients whose accessory renal arteries were all denervated (group IIa), and 11 patients whose accessory renal arteries were not, or only incompletely, denervated (group IIb). The primary endpoint was the change in office systolic BP after 6 months. The procedure was successful in all patients. Group I: mean BP at baseline was 166.2/89.4 ± 20.5/14.6 mm Hg and decreased by -16.6 (p renal denervation in patients with accessory renal arteries is less pronounced than in patients with bilateral single renal arteries. Copyright © 2013 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Renal artery stenosis.

Science.gov (United States)

Tafur-Soto, Jose David; White, Christopher J

2015-02-01

Atherosclerotic renal artery stenosis (RAS) is the single largest cause of secondary hypertension; it is associated with progressive renal insufficiency and causes cardiovascular complications such as refractory heart failure and flash pulmonary edema. Medical therapy, including risk factor modification, renin-angiotensin-aldosterone system antagonists, lipid-lowering agents, and antiplatelet therapy, is advised in all patients. Patients with uncontrolled renovascular hypertension despite optimal medical therapy, ischemic nephropathy, and cardiac destabilization syndromes who have severe RAS are likely to benefit from renal artery revascularization. Screening for RAS can be done with Doppler ultrasonography, CT angiography, and magnetic resonance angiography. Copyright © 2015 Elsevier Inc. All rights reserved.

Renal Sympathetic Denervation System via Intraluminal Ultrasonic Ablation: Therapeutic Intravascular Ultrasound Design and Preclinical Evaluation.

Science.gov (United States)

Chernin, Gil; Szwarcfiter, Iris; Bausback, Yvonne; Jonas, Michael

2017-05-01

To assess the safety and performance of a nonfocused and nonballooned ultrasonic (US) catheter-based renal sympathetic denervation (RDN) system in normotensive swine. RDN with the therapeutic intravascular US catheter was evaluated in 3 experiments: (i) therapeutic intravascular US RDN vs a control group of untreated animals with follow-up of 30, 45, and 90 days (n = 6; n = 12 renal arteries for each group); (ii) therapeutic intravascular US RDN vs radiofrequency (RF) RDN in the contralateral artery in the same animal (n = 2; n = 4 renal arteries); and (iii) therapeutic intravascular US RDN in a recently stent-implanted renal artery (n = 2; n = 4 renal arteries). In the first experiment, therapeutic intravascular US RDN was safe, without angiographic evidence of dissection or renal artery stenosis. Neuronal tissue vacuolization, nuclei pyknosis, and perineuronal inflammation were evident after RDN, without renal artery wall damage. Norepinephrine levels were significantly lower after therapeutic intravascular US RDN after 30, 45, and 90 days compared with the control group (200.17 pg/mg ± 63.35, 184.75 pg/mg ± 44.51, and 203.43 pg/mg ± 58.54, respectively, vs 342.42 pg/mg ± 79.97). In the second experiment, deeper neuronal ablation penetrance was found with therapeutic intravascular US RDN vs RF RDN (maximal penetrance from endothelium of 7.0 mm vs 3.5 mm, respectively). There was less damage to the artery wall after therapeutic intravascular US RDN than with RF RDN, after which edema and injured endothelium were seen. In the third experiment, denervation inside the stent-implanted segments was feasible without damage to the renal artery wall or stent. The therapeutic intravascular US system performed safely and reduced norepinephrine levels. Deeper penetrance and better preservation of vessel wall were observed with therapeutic intravascular US RDN vs RF RDN. Neuronal ablations were observed in stent-implanted renal arteries. Copyright © 2017 SIR. Published

Acute transplant renal artery thrombosis due to distal renal artery stenosis: A case report and review of the literature

OpenAIRE

Fallahzadeh, Mohammad Kazem; Yatavelli, Rajini Kanth; Kumar, Ajay; Singh, Neeraj

2014-01-01

Background: Acute renal artery thrombosis is a devastating complication of renal transplantation that can result in graft loss if not detected early. Surgical and technical errors are the major cause of renal artery thrombosis. In this article, for the first time, we are reporting a case of acute renal artery thrombosis that developed early post-transplantation due to distal renal artery stenosis. Case Presentation: A 71-year-old woman presented with nausea, vomiting and decreased urine outpu...

Diagnostic use of angiotensin converting enzyme (ACE)-inhibited renal scintigraphy in the identification of selective renal artery stenosis in the presence of multiple renal arteries: A case report

International Nuclear Information System (INIS)

Morton, K.A.; Rose, S.C.; Haakenstad, A.O.; Handy, J.E.; Scuderi, A.J.; Datz, F.L.

1990-01-01

In patients with renovascular hypertension, it is unknown whether the angiotensin converting enzyme-(ACE) inhibited renal scan will identify stenosis of a segmental branch of a single renal artery or of an accessory artery where multiple renal arteries are present. Since multiple renal arteries may be present in approximately 25% of all individuals, it will be important to establish whether the ACE-inhibited renal scan is useful in this population. We report a case of stenosis involving a renal artery in a patient with multiple renal arteries, successfully identified by ACE-inhibited renal scintigraphy

Aortic Stent-Graft Infection Following Septic Complications of a Kidney Stone

International Nuclear Information System (INIS)

Berg, H. Rogier van den; Leijdekkers, Vanessa J.; Vahl, Anco

2006-01-01

A 73-year-old man was treated because of a renal pelvis blowout of the left kidney for which he received a nephrostomy catheter without antibiotic prophylaxis. Almost a year previously this patient had undergone endovascular repair of a symptomatic infrarenal abdominal aorta aneurysm. Four weeks after the diagnosis and treatment of the ruptured renal pelvis, a new computed tomography scan and ultrasound-guided fine needle aspiration confirmed the diagnosis of infected aortic stent-graft. An extra-anatomic axillo-uniiliac bypass and graft excision was performed. Two weeks after discharge the patient returned to the hospital with an occlusion of his left renal artery and died of renal failure. This is the first time an infected aortic stent-graft after a renal pelvis blowout has been reported. Although infections of aortic stent-grafts occur rarely, one should be aware of the possibility in aortic stent-graft patients undergoing abdominal procedures without antibiotic prophylaxis

Venous digital subtraction angiography for diagnosis of renal artery stenosis in arterial hypertony

International Nuclear Information System (INIS)

Schoerner, W.; Kempter, H.; Banzer, D.; Aviles, C.; Weiss, T.; Felix, R.

1984-01-01

Venous digital subtraction angiography was performed in 248 patients for the diagnosis of renal arterial stenosis. In 88% of the investigations the stenosis could be found. Comparison of digital angiography and conventional angiography was made for 57 renal arteries (25 investigations). In 52 renal arteries we found the same results with both methods, in 5 renal arteries we found the same results with both methods, in 5 renal arteries the digital angiography showed false positive results. The spatial resolution of digital subtraction angiography is sufficient for the correct diagnosis of significant renal arterial stenosis. With regard to the lower invasion of digital subtraction angiography compared to conventional angiography the first method should be used for clarification of renal arterial hypertension. (orig.)

Multiple Renal Artery Pseudoaneurysms in Patients Undergoing Renal Artery Embolization Following Partial Nephrectomy: Correlation with RENAL Nephrometry Scores

International Nuclear Information System (INIS)

Gupta, Nakul; Patel, Anish; Ensor, Joe; Ahrar, Kamran; Ahrar, Judy; Tam, Alda; Odisio, Bruno; Huang, Stephen; Murthy, Ravi; Mahvash, Armeen; Avritscher, Rony; McRae, Stephen; Sabir, Sharjeel; Wallace, Michael; Matin, Surena; Gupta, Sanjay

2017-01-01

PurposeTo describe the incidence of multiple renal artery pseudoaneurysms (PSA) in patients referred for renal artery embolization following partial nephrectomy and to study its relationship to RENAL nephrometry scores.Materials and MethodsThe medical records of 25 patients referred for renal artery embolization after partial nephrectomy were retrospectively reviewed for the following parameters: size and number of tumors, RENAL nephrometry scores, angiographic abnormalities, technical and clinical outcomes, and estimated glomerular filtration rates (eGFRs) after embolization.ResultsTwenty-four patients had primary renal tumors, while 1 patient had a pancreatic tumor invading the kidney. Multiple tumors were resected in 4 patients. Most patients (92 %) were symptomatic, presenting with gross hematuria, flank pain, or both. Angiography revealed PSA with (n = 5) or without (n = 20) AV fistulae. Sixteen patients (64 %) had multiple PSA involving multiple renal vessels. Higher RENAL nephrometry scores were associated with an increasing likelihood of multiple PSA. Multiple vessels were embolized in 14 patients (56 %). Clinical success was achieved after one (n = 22) or two (n = 3) embolization sessions in all patients. Post-embolization eGFR values at different time points after embolization were not significantly different from the post-operative eGFR.ConclusionA majority of patients requiring renal artery embolization following partial nephrectomy have multiple pseudoaneurysms, often requiring selective embolization of multiple vessels. Higher RENAL nephrometry score is associated with an increasing likelihood of multiple pseudoaneurysms. We found transarterial embolization to be a safe and effective treatment option with no long-term adverse effect on renal function in all but one patient with a solitary kidney.

Multiple Renal Artery Pseudoaneurysms in Patients Undergoing Renal Artery Embolization Following Partial Nephrectomy: Correlation with RENAL Nephrometry Scores

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Gupta, Nakul [Houston Methodist Hospital (United States); Patel, Anish [The University of Texas Southwestern Medical Center (United States); Ensor, Joe [Houston Methodist Research Institute, The Houston Methodist Cancer Center (United States); Ahrar, Kamran; Ahrar, Judy; Tam, Alda; Odisio, Bruno; Huang, Stephen; Murthy, Ravi; Mahvash, Armeen; Avritscher, Rony; McRae, Stephen; Sabir, Sharjeel; Wallace, Michael [The University of Texas MD Anderson Cancer Center, Department of Interventional Radiology (United States); Matin, Surena [The University of Texas MD Anderson Cancer Center, Department of Urology (United States); Gupta, Sanjay, E-mail: sgupta@mdanderson.org [The University of Texas MD Anderson Cancer Center, Department of Interventional Radiology (United States)

2017-02-15

PurposeTo describe the incidence of multiple renal artery pseudoaneurysms (PSA) in patients referred for renal artery embolization following partial nephrectomy and to study its relationship to RENAL nephrometry scores.Materials and MethodsThe medical records of 25 patients referred for renal artery embolization after partial nephrectomy were retrospectively reviewed for the following parameters: size and number of tumors, RENAL nephrometry scores, angiographic abnormalities, technical and clinical outcomes, and estimated glomerular filtration rates (eGFRs) after embolization.ResultsTwenty-four patients had primary renal tumors, while 1 patient had a pancreatic tumor invading the kidney. Multiple tumors were resected in 4 patients. Most patients (92 %) were symptomatic, presenting with gross hematuria, flank pain, or both. Angiography revealed PSA with (n = 5) or without (n = 20) AV fistulae. Sixteen patients (64 %) had multiple PSA involving multiple renal vessels. Higher RENAL nephrometry scores were associated with an increasing likelihood of multiple PSA. Multiple vessels were embolized in 14 patients (56 %). Clinical success was achieved after one (n = 22) or two (n = 3) embolization sessions in all patients. Post-embolization eGFR values at different time points after embolization were not significantly different from the post-operative eGFR.ConclusionA majority of patients requiring renal artery embolization following partial nephrectomy have multiple pseudoaneurysms, often requiring selective embolization of multiple vessels. Higher RENAL nephrometry score is associated with an increasing likelihood of multiple pseudoaneurysms. We found transarterial embolization to be a safe and effective treatment option with no long-term adverse effect on renal function in all but one patient with a solitary kidney.

Routine short-term ureteral stent in living donor renal transplantation: introduction of a simple stent removal technique without using anesthesia and cystoscope.

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Dong, J; Lu, J; Zu, Q; Yang, S; Sun, S; Cai, W; Zhang, L; Zhang, X

2011-12-01

We evaluated routine short-time insertion of ureteral stent in living donor renal transplant at a single center. It was easy to remove the stent without cystoscopy and anesthesia. Between October 2007 and July 2010, a single surgeon performed 76 living donor renal transplantations at one institute. All recipients underwent extravesical ureteroneocystostomy with a 2-0 silk suture passed through the venting side hole of the double-J stent into the bladder; a quadruple knot prevented the suture's slippage or distraction from the stent. After removal of the indwelling catheter at 5 days posttransplantation, the 2-0 silk passed with the urinary stream within 72 hours. The double-J stent was removed at 7 to 10 (mean 8.4) days after kidney transplantation by pulling the 2-0 silk out of the urethral orifice without anesthesia or cystoscopy. There was only one case of stenosis, which was resolved by surgery. No patient developed urinary leakage. There were three episodes of urinary tract infection in 70 patients during first 6 months' follow-up. Routine short-term stenting is a safe and effective technique in living donor renal transplantation. Removal of the stent is feasible without cystoscopy or anesthesia. Copyright © 2011 Elsevier Inc. All rights reserved.

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

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Hiroshi Fujita

2014-12-01

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

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

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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.

Renal artery origins: best angiographic projection angles.

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Verschuyl, E J; Kaatee, R; Beek, F J; Patel, N H; Fontaine, A B; Daly, C P; Coldwell, D M; Bush, W H; Mali, W P

1997-10-01

To determine the best projection angles for imaging the renal artery origins in profile. A mathematical model of the anatomy at the renal artery origins in the transverse plane was used to analyze the amount of aortic lumen that projects over the renal artery origins at various projection angles. Computed tomographic (CT) angiographic data about the location of 400 renal artery origins in 200 patients were statistically analyzed. In patients with an abdominal aortic diameter no larger than 3.0 cm, approximately 0.5 mm of the proximal part of the renal artery and origin may be hidden from view if there is a projection error of +/-10 degrees from the ideal image. A combination of anteroposterior and 20 degrees and 40 degrees left anterior oblique projections resulted in a 92% yield of images that adequately profiled the renal artery origins. Right anterior oblique projections resulted in the least useful images. An error in projection angle of +/-10 degrees is acceptable for angiographic imaging of the renal artery origins. Patients sex, site of interest (left or right artery), and local diameter of the abdominal aorta are important factors to consider.

Feasibility and Safety of Transradial Arterial Approach for Simultaneous Right and Left Vertebral Artery Angiographic Studies and Stenting

International Nuclear Information System (INIS)

Yip, H.-K.; Youssef, Ali A.; Chang, W.-N.; Lu, C.-H.; Yang, C.-H.; Chen, S.-M.; Wu, C.-J.

2007-01-01

Objectives. This study investigated whether the transradial artery (TRA) approach using a 6-French (F) Kimny guiding catheter for right vertebral artery (VA) angiographic study and stenting is safe and effective for patients with significant VA stenosis. Background. The TRA approach is commonly performed worldwide for both diagnostic cardiac catheterization and catheter-based coronary intervention. However, to our knowledge, the safety and feasibility of left and right VA angiographic study and stenting, in the same procedure, using the TRA approach for patients with brain ischemia have not been reported. Methods. The study included 24 consecutive patients (22 male, 2 female; age, 63-78 years). Indications for VA angiographic study and stenting were (1) prior stroke or symptoms related to vertebrobasilar ischemia and (2) an asymptomatic but vertebral angiographic finding of severe stenosis (>70%). A combination of the ipsilateral and retrograde-engagement technique, which involved a looping 6-F Kimny guiding catheter, was utilized for VA angiographic study. For VA stenting, an ipsilateral TRA approach with either a Kimny guiding catheter or a left internal mammary artery guiding catheter was utilized in 22 patients and retrograde-engagement technique in 2 patients. Results. A technically successful procedure was achieved in all patients, including left VA stenting in 15 patients and right VA stenting in 9 patients. The mean time for stenting (from engagement to stent deployment) was 12.7 min. There were no vascular complications or mortality. However, one patient suffered from a transient ischemic attack that resolved within 3 h. Conclusion. We conclude that TRA access for both VA angiographic study and VA stenting is safe and effective, and provides a simple and useful clinical tool for patients unsuited for femoral arterial access

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

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Ersan TatlI

2017-05-01

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

Luminal flow amplifies stent-based drug deposition in arterial bifurcations.

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Vijaya B Kolachalama

2009-12-01

Full Text Available Treatment of arterial bifurcation lesions using drug-eluting stents (DES is now common clinical practice and yet the mechanisms governing drug distribution in these complex morphologies are incompletely understood. It is still not evident how to efficiently determine the efficacy of local drug delivery and quantify zones of excessive drug that are harbingers of vascular toxicity and thrombosis, and areas of depletion that are associated with tissue overgrowth and luminal re-narrowing.We constructed two-phase computational models of stent-deployed arterial bifurcations simulating blood flow and drug transport to investigate the factors modulating drug distribution when the main-branch (MB was treated using a DES. Simulations predicted extensive flow-mediated drug delivery in bifurcated vascular beds where the drug distribution patterns are heterogeneous and sensitive to relative stent position and luminal flow. A single DES in the MB coupled with large retrograde luminal flow on the lateral wall of the side-branch (SB can provide drug deposition on the SB lumen-wall interface, except when the MB stent is downstream of the SB flow divider. In an even more dramatic fashion, the presence of the SB affects drug distribution in the stented MB. Here fluid mechanic effects play an even greater role than in the SB especially when the DES is across and downstream to the flow divider and in a manner dependent upon the Reynolds number.The flow effects on drug deposition and subsequent uptake from endovascular DES are amplified in bifurcation lesions. When only one branch is stented, a complex interplay occurs - drug deposition in the stented MB is altered by the flow divider imposed by the SB and in the SB by the presence of a DES in the MB. The use of DES in arterial bifurcations requires a complex calculus that balances vascular and stent geometry as well as luminal flow.

Iliac Artery Stent Placement Relieves Claudication in Patients with Iliac and Superficial Femoral Artery Lesions

International Nuclear Information System (INIS)

Ichihashi, Shigeo; Higashiura, Wataru; Itoh, Hirofumi; Sakaguchi, Shoji; Kichikawa, Kimihiko

2013-01-01

Purpose. To evaluate the efficacy of iliac artery stent placement for relief of claudication in patients with both iliac and superficial femoral artery (SFA) lesions. Methods. Stent placement for only iliac artery occlusive disease was performed in 94 limbs (74 patients) with both iliac and SFA occlusive disease on the same limb. All procedures were performed because intermittent claudication did not improve after continuation of antiplatelet medication therapy and home-based exercise for 3 months. Rutherford classification was 2 in 20 limbs and 3 in 74 limbs. Patients with critical limb ischemia were excluded. Median duration of follow-up was 40 months. Primary patency rates of the iliac stent, clinical improvement rates, and risk factors for requiring additional SFA procedures were evaluated. Results. Primary patency rates of the iliac stent at 1, 3, 5, and 7 years were 97, 93, 79, and 79 %, respectively. The initial clinical improvement rate was 87 %. Continued clinical improvement rates at 1, 3, 5, and 7 years were 87, 81, 69, and 66 %, respectively. SFA Trans-Atlantic Inter-Society Consensus (TASC) II C/D lesion was a significant risk factor for requiring additional SFA procedures. Conclusion. Intermittent claudication was relieved by iliac stent placement in most patients with both iliac and SFA lesions. Thus, the indications for treatment of the SFA intended for claudicants should be evaluated after treatment of the iliac lesion.

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

International Nuclear Information System (INIS)

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

2008-01-01

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

Anatomic variations of the renal vessels: focus on the precaval right renal artery.

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Bouali, Ourdia; Labarre, David; Molinier, François; Lopez, Raphaël; Benouaich, Vincent; Lauwers, Frédéric; Moscovici, Jacques

2012-07-01

The aim of this study was to determine the prevalence of precaval right renal artery and to investigate the distribution of renal arteries and veins. We discuss a theory of development of renal vascular variants. We retrospectively reviewed 120 arterial phase contrast material-enhanced spiral computerized tomography scans of the abdomen (1- to 2-mm section thickness) performed during a two-month period. Forty percent of the study group (48 patients) had one artery and one vein on each side, with typical course. There was a 9.17% prevalence of precaval right renal artery: 10 patients had a lower pole accessory artery in precaval position and one patient had the main and the accessory arteries that pass anterior to the inferior vena cava. In these cases, associated variations of renal vessels were higher than in the patients without precaval artery variant. There were multiple arteries in 28.3% of the right kidneys and in 26.7% of the left ones. Variants of the right renal vein consisted in multiple veins in 20% (24 cases). We detected no case of multiple left renal veins, but we described variations of its course (circum- or retroaortic vein) in 9.17% (11 cases). Twenty-six patients (21.7%) had associated variations of the renal pedicle. The current technical support allows for a minimally invasive study of vessels anatomy. In our study the prevalence of a precaval right renal artery appears to be higher than previously reported (9.17%). Knowledge on anatomical variations of right renal artery and associated renal vessels variations has major clinical implications.

Drug diffusion and biological responses of arteries using a drug-eluting stent with nonuniform coating

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Saito N

2016-03-01

Full Text Available Noboru Saito, Yuhei Mori, Sayaka Uchiyama Terumo Corporation R&D Center, Inokuchi, Nakai-machi, Ashigarakami-gun, Kanagawa, Japan Abstract: The purpose of this study was to determine the effect of a nonuniform coating, abluminal-gradient coating (AGC, which leaves the abluminal surface of the curves and links parts of the stent free from the drug coating, on the diffusion direction of the drug and the biological responses of the artery to drug-eluting stent (DES by comparing the AGC-sirolimus stent and the conventional full-surface coating (CFC sirolimus stent. The study aimed to verify whether the AGC approach was appropriate for the development of a safer DES, minimizing the risks of stent thrombosis due to delayed endothelialization by the drug and distal embolization due to cracking of the coating layer on the hinge parts of the DES on stent expansion. In the in vitro local drug diffusion study, we used rhodamine B as a model drug, and rhodamine B released from the AGC stent diffused predominantly into the abluminal side of the alginate artery model. Conversely, rhodamine B released from the CFC stent quickly spread to the luminal side of the artery model, where endothelial cell regeneration is required. In the biological responses study, the luminal surface of the iliac artery implanted with the AGC-sirolimus stent in a rabbit iliac artery for 2 weeks was completely covered with endothelial-like cells. On the other hand, the luminal surface of the iliac artery implanted with the CFC-sirolimus stent for 2 weeks only showed partial coverage with endothelial-like cells. While thrombosis was observed in two of the three CFC-sirolimus stents, it was observed in only one of the three AGC-sirolimus stents. Taken together, these findings indicate that the designed nonuniform coating (AGC is an appropriate approach to ensure a safer DES. However, the number of studies is limited and a larger study should be conducted to reach a statistically

Iliac artery stenting in patients with poor distal runoff: Influence of concomitant infrainguinal arterial reconstruction.

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Timaran, Carlos H; Ohki, Takao; Gargiulo, Nicholas J; Veith, Frank J; Stevens, Scott L; Freeman, Michael B; Goldman, Mitchell H

2003-09-01

Inadequate infrainguinal runoff is considered an important risk factor for iliac stent failure. However, the influence of concomitant infrainguinal arterial reconstruction (CIAR) on iliac stent patency is unknown. This study evaluated the influence of CIAR on outcome of iliac angioplasty and stenting (IAS) in patients with poor distal runoff. Over 5 years (1996 to 2001), 68 IAS procedures (78 stents) were performed in 62 patients with poor distal runoff (angiographic runoff score >or=5). The SVS/AAVS reporting standards were followed to define outcome variables and risk factors. Data were analyzed with both univariate analysis (Kaplan-Meier method [K-M]) and regression analysis (Cox proportional hazards model). Indications for iliac artery stenting were disabling claudication (59%) and limb salvage (41%). Of the 68 procedures, IAS with CIAR was performed in 31 patients (46%), and IAS alone was performed in 37 patients (54%). Patients undergoing IAS with CIAR were older (P =.03) and had more extensive and multifocal iliac artery occlusive disease, with more TASC (TransAtlantic Inter-Society Consensus) type C lesions (P =.03), compared with patients undergoing IAS alone. No other significant differences in risk factors were noted. Runoff scores between patients undergoing IAS with CIAR and those undergoing IAS alone were not significantly different (median runoff scores, 6 [range, 5-8] and 7 [range, 5-9], respectively; P =.77). Primary stent patency rate at 1, 3, and 5 years was 87%, 54%, and 42%, respectively, for patients undergoing IAS with CIAR, and was 76%, 66%, and 55%, respectively, for patients undergoing IAS. Univariate analysis revealed that primary stent patency rate was not significantly different between the 2 groups (K-M, log-rank test, P =.81). Primary graft patency rate for CIAR was 81%, 52%, and 46% at 1, 3, and 5 years, respectively. Performing CIAR did not affect primary iliac stent patency (relative risk, 1.1; 95% confidence interval, 0.49-2.47; P

ILIAC-ARTERY URETERAL-FISTULA ASSOCIATED WITH AN INDWELLING URETERAL STENT

NARCIS (Netherlands)

ZWEERS, HMM; VANDRIEL, MF; MENSINK, HJA

1991-01-01

We report on a patient with an ureteroiliac artery fistula, which developed after double J stenting. The stent was introduced because of unilateral hydronephrosis 2 months after a Wertheim-Meigs operation preceded by cesium application. The presenting symptom of gross hematuria was initially

Preliminary application of 320-detector spiral CT with ECG editing for assessing coronary artery in-stent restenosis

International Nuclear Information System (INIS)

Li Zhiming; Tan Lilian; Li Shuxin; Fu Xi; He Weihong; Liu Ke; Huang Yong; Yu Lin

2011-01-01

Objective: To determine the value of 320-detector spiral CT with retrospective ECG gating and editing software for detecting coronary artery in-stent restenosis. Methods: CT scans of 14 patients with coronary artery stnets were retrospectively analyzed. The examinations were performed using a 320-detector spiral CT scanner and retrospective ECG gating combined with ECG editing software. The image quality of reconstructed coronary artery in-stents was compared before and after the editing of synchronously recorded ECG. The paired-sample t test was used for statistical analysis. Results: Before ECG editing, arrhythmia and in-stent artifact resulted in image blurring, missing arterial segments, significant stepladder artifacts or non-visualization of the interior of stents. Of 14 cases before ECG editing, in-stent restenosis was detected in 10 and patency in 3. The coronary artery stent and distal bifurcation were delineated in one patient. After ECG editing, the image quality of coronary artery stents was improved with detection of in-stent restenosis (4 cases) including the one case that not evaluable before ECG editing. The average image quality score before ECG editing (2.14±0.86) was significantly (P<0.001) lower than that after ECG editing (3.07±0.73). Conclusion: Retrospective ECG gating combined with ECG editing of 320-detector spiral CT can reduce the artifacts produced by arrhythmia or in-stent swings and improve the imaging quality of coronary artery stents. (authors)

The efficacy of hemodialysis in interventional therapy in coronary artery disease patients with chronic renal insufficiency.

Science.gov (United States)

Zhai, Hongxia; Li, Liang; Yin, Yaxin; Zhang, Jinjin; Chen, Haiwei; Liu, Runmei; Xia, Yun-feng

2016-01-01

The aim of this study was to explore the efficacy and safety of hemodialysis in interventional therapy for patients with coronary artery disease combined with chronic renal insufficiency. With the aging and social development, the number of coronary artery disease patients with chronic renal insufficiency gradually increased. Total 58 coronary heart disease patients with chronic renal dysfunction were selected. These patients were characterized with typical angina symptoms and typical electrocardiogram (ECG) changes of onset angina. Continuous oral administration of sodium bicarbonate tablets 1 g 3/day × 3 days and slow intravenous input sodium chloride 1000 ∼1500 mL 3-12 h before operation were given. By this way, all patients were treated by hydration and alkalization. After percutaneous coronary intervention (PCI) treatment, patients were immediately transferred to undergo 4 h of dialysis treatment without removing indwelling of femoral artery puncture sheath tube to protect renal function. Changes in renal function including serum creatinine, glomerular filtration rate, and urine were observed and recorded. All patients were successfully underwent PCI treatment. Within one month after PCI, there were no obvious complication and no stent thrombosis occurred. Among of 58 patients, 56 cases showed no significant increase in serum creatinine levels compared with those before operation. However, serum creatinine level of one patient increased to 251 umol/L and one patient still required permanent dialysis. Using hemodialysis in interventional therapy in coronary artery disease patients with chronic renal insufficiency could significantly improve the prognosis of the patients.

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

Science.gov (United States)

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

2018-02-01

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

Potential mechanisms of in-stent occlusion in the femoropopliteal artery: an angioscopic assessment.

Science.gov (United States)

Ishihara, Takayuki; Iida, Osamu; Okamoto, Shin; Fujita, Masashi; Masuda, Masaharu; Nanto, Kiyonori; Shiraki, Tatsuya; Kanda, Takashi; Tsujimura, Takuya; Okuno, Shota; Yanaka, Koji; Uematsu, Masaaki

2017-10-01

Although stent implantation has become widespread for the treatment of patients with peripheral artery disease with femoropopliteal (FP) lesions, in-stent restenosis, especially in-stent occlusion (ISO), remains as a major concern for refractory recurrence. Furthermore, the mechanisms of ISO in FP lesions have not been well elucidated. We performed angioscopy for 6 lesions (bare-metal stent: 3, drug-eluting stent: 3) from 5 patients (mean age 74 ± 10 years, male 40 %) with ISO in the FP artery immediately after wire-passing or thrombus aspiration. The presence of thrombus as well as the presence and location of organic stenosis were evaluated. Median duration from stent implantation to angioscopic evaluation was 1099.5 (514.5-2272.5) days, while the duration from recurrence of symptoms to angioscopic evaluation was 45 (5.75-60) days. Mixed thrombi were observed in all stents. Organic stenosis was detected at the proximal edge of the stents in 5 lesions. Organic stenosis was observed at the overlapping segment of the stent in one lesion. The distal edge of the stents could be evaluated in 3 lesions, and all of them showed organic stenosis at the site. Mixed thrombi and organic stenosis were observed in all stents. Partial development of organic stenosis in a stent followed by thrombus formation may be the potential mechanism of the development of ISO in the FP artery though the sample size of this study was small and it had no serial angioscopic data so that we should consider it as preliminary one at best.

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

Drug-eluting versus bare-metal stents in large coronary arteries

DEFF Research Database (Denmark)

Kaiser, Christoph; Galatius, Soeren; Erne, Paul

2010-01-01

Recent data have suggested that patients with coronary disease in large arteries are at increased risk for late cardiac events after percutaneous intervention with first-generation drug-eluting stents, as compared with bare-metal stents. We sought to confirm this observation and to assess whether...

Interventional radiological management of complications in renal transplantation

International Nuclear Information System (INIS)

Popovic, P.; Surlan, M.

2004-01-01

Background. The most frequent radiologically evaluated and treated complications in renal transplantation are perirenal and renal fluid collection and abnormalities of the vasculature and collecting system. Renal and perirenal fluid collection is usually treated successfully with percutaneous drainage. Doppler US, MRA and digital subtraction angiography (DSA) are most important in the evaluation of vascular complications of renal transplantation and management of the endovascular therapy. Conclusions. Stenosis, the most common vascular complication, occurs in 1% to 12% of transplanted renal arteries and represents a potentially curable cause of hypertension following transplantation and/or renal dysfunction. Treatment with percutaneous transluminal renal angioplasty (PTRA) or PTRA with stent has been technically successful in 82 to 92% of the cases, and graft salvage rate has ranged from 80-100%. Complications such as arterial and vein thrombosis are uncommon. Intrarenal A/V fistulas and pseudoaneurysms are occasionally seen after biopsy, the treatment requires superselective embolisation. Urologic complications are relatively uncommon; they consist predominantly of the urinary leaks and urethral obstruction. Interventional treatment consists of percutaneous nephrostomy, balloon dilation, insertion of the double J stents, metallic stent placement and external drainage of the extrarenal collections. The aim of the paper is to review the role of interventional radiology in the management of complications in renal transplantation. (author)

Dual-therapy stent technology for patients with coronary artery disease : A great catch?

NARCIS (Netherlands)

Kalkman, D.N.

2018-01-01

This thesis investigates the possible advantages of a new stent technology that aims to improve care for patients with coronary artery disease. The COMBO stent (OrbusNeich Medical BV, The Netherlands) contains a dual-therapy stent technology. The stent combines two techniques: a sirolimus-elution

Transluminal endovascular stent-graft for the treatment of aortic aneurysms

Energy Technology Data Exchange (ETDEWEB)

Lee, Do Yun; Chang, Byung Chul; Shim, Won Heum; Cho, Seung Yun; Chung, Nam Sik; Kwon, Hyuk Moon; Lee, Young Joon; Lee, Jong Tae [Yonsei University College of Medicine, Seoul (Korea, Republic of)

1995-09-15

The standard treatment for aortic aneurysms is surgical replacement with a prosthetic graft. Currently there is great interest in endoluminal intervention for treatment of aortic aneurysm. The purpose of this study was to evaluate the safety and effectiveness of endoluminally placed Stent-graft for the treatment of aortic aneurysms. Transluminal endovascular Stent-graft placements were attempted in 9 patients with infra-renal aortic aneurysms(n 6), thoracic aortic aneurysm(n = 1), and aortic dissection(n = 2). The endovascular Stent-grafts were custom-designed for each patient and were constructed of self-expandable modified Gianturco Stents covered with polytetrafluroethylene. The Stent-grafts were introduced through a 16-18 French sheath and expanded to 17-30 mm in diameter. The endovascular therapy was performed using a common femoral artery cutdown with local anesthesia. The endovascular Stent-graft deployment was achieved in 7 of 9 patients. Two cases failed deployment of the Stent-graft due to iliac artery stenosis and tortousity. There were complete thrombosis of the thoracic and infra-renal aortic aneurysm surround the Stent-graft in 3 patients, and persistent leak with partial thrombosis in 2. Two patients with aortic dissection were successfully treated by obliteration of entry tears. There were no major complication associated with Stent-graft placement. These preliminary results show that transluminal endovascular Stent-grafts offer great promise and good results. Further investigation is needed to establish its long-term safety and efficacy.

Transluminal endovascular stent-graft for the treatment of aortic aneurysms

International Nuclear Information System (INIS)

Lee, Do Yun; Chang, Byung Chul; Shim, Won Heum; Cho, Seung Yun; Chung, Nam Sik; Kwon, Hyuk Moon; Lee, Young Joon; Lee, Jong Tae

1995-01-01

The standard treatment for aortic aneurysms is surgical replacement with a prosthetic graft. Currently there is great interest in endoluminal intervention for treatment of aortic aneurysm. The purpose of this study was to evaluate the safety and effectiveness of endoluminally placed Stent-graft for the treatment of aortic aneurysms. Transluminal endovascular Stent-graft placements were attempted in 9 patients with infra-renal aortic aneurysms(n 6), thoracic aortic aneurysm(n = 1), and aortic dissection(n = 2). The endovascular Stent-grafts were custom-designed for each patient and were constructed of self-expandable modified Gianturco Stents covered with polytetrafluroethylene. The Stent-grafts were introduced through a 16-18 French sheath and expanded to 17-30 mm in diameter. The endovascular therapy was performed using a common femoral artery cutdown with local anesthesia. The endovascular Stent-graft deployment was achieved in 7 of 9 patients. Two cases failed deployment of the Stent-graft due to iliac artery stenosis and tortousity. There were complete thrombosis of the thoracic and infra-renal aortic aneurysm surround the Stent-graft in 3 patients, and persistent leak with partial thrombosis in 2. Two patients with aortic dissection were successfully treated by obliteration of entry tears. There were no major complication associated with Stent-graft placement. These preliminary results show that transluminal endovascular Stent-grafts offer great promise and good results. Further investigation is needed to establish its long-term safety and efficacy

Effect of longitudinal anatomical mismatch of stenting on the mechanical environment in human carotid artery with atherosclerotic plaques.

Science.gov (United States)

Fan, Zhenmin; Liu, Xiao; Sun, Anqiang; Zhang, Nan; Fan, Zhanming; Fan, Yubo; Deng, Xiaoyan

2017-10-01

Longitudinal anatomic mismatch (LAM) of stenting (i.e., a stenotic artery segment is not fully covered by a deployed stent) worsens the mechanical environment in the treated artery, which most likely is the cause for the associated high risks of restenosis, myocardial infarction and stent thrombosis. To probe the possibility, we constructed a patient-specific carotid model with two components of plaques (lipid and calcified plaque) based on MRI images; we numerically compared three different stenting scenarios in terms of von Mises stress (VMS) distribution in the treated arteries, namely, the short stenting (LAM), the medium stenting and the long stenting. The results showed that the short stenting led to more areas with abnormally high VMS along the inner surface of the treated artery with a much higher surface-averaged VMS at the distal end of the stent than both the medium and long stenting. While the VMS distribution in the calcified plaques was similar for the three stenting models, it was quite different in the lipid plaques among the three stenting models. The lipid plaque of the short-stent model showed more volume of the lipid plaque subjected to high VMS than those of the other two models. Based on the obtained results, we may infer that the short stenting (i.e., LAM) may aggravate vascular injury due to high VMS on the artery-stent interaction surface and within the lipid plaque. Therefore, to obtain a better outcome, a longer stent, rather than a short one, might be needed for arterial stenting. Copyright © 2017 IPEM. Published by Elsevier Ltd. All rights reserved.

Late effects of low-energy gamma-emitting stents in a rabbit iliac artery model

International Nuclear Information System (INIS)

Strauss, Bradley H.; Li, Chris; Whittingham, Heather A.; Tio, Fermin O.; Kutryk, Michael J.B.; Janicki, Christian; Sparkes, John D.; Turnlund, Todd; Sweet, William L.

2002-01-01

Purpose: To determine the long-term dose response of novel low-dose γ-emitting stents in a rabbit iliac artery model. Methods and Materials: Control stents (n=24) and 103 Pd stents 1.0 to 4.0 mCi (n=36) were implanted in the iliac arteries of 30 New Zealand rabbits. Stents were evaluated by intravascular ultrasound (immediately post procedure and before killing) and by histomorphometry. Results: At 26 weeks, 28 rabbits were killed, with no evidence of stent thrombosis. In the body of the stent there was a dose-response relationship with 50% inhibition of intimal hyperplasia at the highest activity compared to control stents (p=0.07) and a significant increase in intimal hyperplasia at the lowest activity (p 103 Pd stents is feasible with reduction of in-stent hyperplasia in a dose-related manner. However, significant narrowing at the stent edges, increased in-stent hyperplasia at lower activities, and incomplete vascular healing with persistence of immature neointima at higher activities are significant limitations

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.

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

Studies on diagnosis and treatment of renal artery stenosis

NARCIS (Netherlands)

P. Krijnen (Pieta)

2004-01-01

textabstractThis thesis describes studies on ~onosis and treatment of renal artery stenosis in patients with drug-resistant hypertension. In Chapter 1, the clinical problem of renal artery stenosis is discussed. Renal artery stenosis, a narrowing of the renal artery, is a potential cause of

Restenosis after stenting in symptomatic vertebral arterial orifice disease and considerations for better outcome

Science.gov (United States)

Chang, Jun Young; Park, Hyun; Kwon, Oki

2017-01-01

We have performed stenting in 11 patients with symptomatic vertebral arterial orifice stenosis refractory to medical treatment or impairment in anterior circulation. Three of the 11 patients experienced asymptomatic severe in-stent restenosis or occlusion. Bare metal stents were used in those three patients, two of whom received revascularization therapy. Development of sufficient cervical collateral channels reconstituting the distal vertebral artery was the common feature in patients with asymptomatic in-stent restenosis. In selecting appropriate stents, consideration of mechanical strength and drug-eluting properties of a stent according to characteristics of the target vessel is important to reduce the risk of in-stent restenosis. Any decision to perform revascularization should be based on the presence of abundant cervical collaterals as well as clinical symptoms of vertebrobasilar ischemia. PMID:28304206

Renal artery origins and variations: angiographic evaluation of 855 consecutive patients.

Science.gov (United States)

Ozkan, Uğur; Oğuzkurt, Levent; Tercan, Fahri; Kizilkiliç, Osman; Koç, Zafer; Koca, Nihal

2006-12-01

To determine angiographically the origins and variations of renal arteries. The study included 855 consecutive patients (163 females, 692 males; mean age, 61 years) living in the Cukurova region of Turkey, who underwent either aortofemoropopliteal (AFP) angiography for the investigation of peripheral arterial disease, or renal angiography for renovascular hypertension, and were prospectively evaluated. Renal arteries were visualized by non-selective catheterization during AFP angiography and by selective or non-selective catheterization during renal angiography. Locations of renal artery origins and renal artery variations, including the presence of extra renal arteries and division patterns were analyzed on angiograms. The origin of main renal arteries off the aorta was between the upper margin of L1 and lower margin of L2 vertebra in 98% of the patients, and in 74%, this was the origin of extra renal arteries. The most common location for renal artery origin was the L1-L2 intervertebral disc level. A single renal artery was present in both kidneys in 76% of patients. Renal artery variations included multiple arteries in 24%, bilateral multiple arteries in 5%, and early division in 8% of the cases. Additional renal arteries on the right side were found in 16% and on the left side in 13% of cases. Of all the extra renal arteries, the percentage of accessory and aberrant renal arteries were 49% and 51%, respectively. Renal arteries originated between the first and the second lumbar vertebral levels in most patients. Extra renal arteries were quite frequent. These results should be kept in mind when a non-invasive diagnostic search is performed for renal artery stenosis, or when renal surgery related to renal arteries is performed.

Off-pump coronary artery bypass grafting or percutaneous transluminal coronary angioplasty with stenting for proximal left anterior descending coronary artery disease?

NARCIS (Netherlands)

Drenth, Derk Jan

2005-01-01

This thesis describes and discusses the results of a prospective randomized controlled clinical trial comparing percutaneous coronary angioplasty with stenting (stenting) and off-pump coronary artery bypass grafting with a left internal mammary artery (surgery) in patients with a high-grade stenosis

Dependence of renal blood flow on renal artery stenosis measured using CT angiography

Energy Technology Data Exchange (ETDEWEB)

Luedemann, Lutz [Charite - Universitaetsmedizin Berlin (Germany). Dept. of Radiotherapy; Nafz, B.; Persson, P. [Charite - Universitaetsmedizin Berlin (Germany). Inst. for Vegetative Physiology; Elsner, F. [Krankenhaus am Urban, Berlin (Germany). Dept. of Anesthesiology; Grosse-Siestrup, C.; Meissler, M. [Charite - Universitaetsmedizin Berlin (Germany). Experimental Animal Unit; Gutberlet, M. [Charite - Universitaetsmedizin Berlin (Germany). Dept. of Diagnostic and Interventional Radiology; Univ. Leipzig/ Leipzig Heart Center (Germany). Dept. of Diagnostic and Interventional Radiology; Lengsfeld, P.; Voth, M. [Bayer-Schering Pharma AG, Berlin (Germany). Global Medical Affairs Diagnostic Imaging

2011-03-15

The present study investigates the suitability of computed tomography angiography (CTA) depicting the degree of renal artery stenosis for estimating renal blood flow (RBF) in a kidney. Materials and Methods: We investigated renal artery stenosis assessment by CTA in eight adult female hybrid pigs with an ultrasound probe implanted at the renal vein for RBF measurement. An inflatable metal-free cuff was placed around the renal artery to control the RBF. The RBF was then reduced in four steps. For each reduced RBF value and baseline RBF, CTA with a reconstructed slice thickness of 0.625 mm was performed in the arterial phase following injection of 80 ml of nonionic intravenous contrast medium. The radius of the stenotic and non-stenotic renal artery segment was measured in the reconstructed images. Results: A significant linear correlation (p < 0.0001) was found between the relative apparent stenosis (calculated as the ratio of the radii of the actual stenotic segment and a non-stenotic renal artery segment) and RBF. The linear regression yielded a slope of 0.57 and a y-axis of 24.1 %. A significant linear correlation (p < 0.0001) was also found between the relative true stenosis (the ratio of the radii of the actual stenotic segment and a non-stenotic renal artery segment at baseline) and the RBF. The linear regression yielded a slope of 0.67 and a y-axis of 13.8 %. Conclusion: The results show that the relative stenosis apparent on CTA differs from the true degree of renal artery stenosis. Nevertheless, the degree of renal artery stenosis determined by CTA provides a reliable estimate of the resulting RBF reduction. (orig.)

Dependence of renal blood flow on renal artery stenosis measured using CT angiography

International Nuclear Information System (INIS)

Luedemann, Lutz; Nafz, B.; Persson, P.; Elsner, F.; Grosse-Siestrup, C.; Meissler, M.; Gutberlet, M.; Univ. Leipzig/ Leipzig Heart Center; Lengsfeld, P.; Voth, M.

2011-01-01

The present study investigates the suitability of computed tomography angiography (CTA) depicting the degree of renal artery stenosis for estimating renal blood flow (RBF) in a kidney. Materials and Methods: We investigated renal artery stenosis assessment by CTA in eight adult female hybrid pigs with an ultrasound probe implanted at the renal vein for RBF measurement. An inflatable metal-free cuff was placed around the renal artery to control the RBF. The RBF was then reduced in four steps. For each reduced RBF value and baseline RBF, CTA with a reconstructed slice thickness of 0.625 mm was performed in the arterial phase following injection of 80 ml of nonionic intravenous contrast medium. The radius of the stenotic and non-stenotic renal artery segment was measured in the reconstructed images. Results: A significant linear correlation (p < 0.0001) was found between the relative apparent stenosis (calculated as the ratio of the radii of the actual stenotic segment and a non-stenotic renal artery segment) and RBF. The linear regression yielded a slope of 0.57 and a y-axis of 24.1 %. A significant linear correlation (p < 0.0001) was also found between the relative true stenosis (the ratio of the radii of the actual stenotic segment and a non-stenotic renal artery segment at baseline) and the RBF. The linear regression yielded a slope of 0.67 and a y-axis of 13.8 %. Conclusion: The results show that the relative stenosis apparent on CTA differs from the true degree of renal artery stenosis. Nevertheless, the degree of renal artery stenosis determined by CTA provides a reliable estimate of the resulting RBF reduction. (orig.)

Primary Stenting of Subclavian and Innominate Artery Occlusive Disease: A Single Center's Experience

International Nuclear Information System (INIS)

Brountzos, E. N.; Petersen, B.; Binkert, C.; Panagiotou, I.; Kaufman, J. A.

2004-01-01

Purpose: To review immediate and midterm results of primary stenting for innominate and subclavian artery occlusive lesions. Methods: Retrospective data were collected from 48 consecutive symptomatic patients (27 men and 21 women, median age 64 years) having 49 subclavian and innominate artery lesions treated with stenting. Of the patients 52% had concomitant ischemic heart disease, and 30% had carotid and/or vertebral artery disease. Indication for treatment was vertebrobasilar insufficiency (VBI) in 16.6% of the patients; upper limb ischemia (ULI) in 31.3%; VBI and ULI in 12.5%; transient ischemic attack in 16.7%; angina in 12.5% before or after left internal mammary artery-to-coronary artery bypass grafting; and leg claudication in 10.4% before or after axillofemoral bypass grafting. Balloon-expandable stents were used in 44 lesions and self-expandable stents in 5 lesions. In total, 53 stents were placed in 48 patients. Results: Technical success was 96%, and clinical success 94%. We encountered four complications (two puncture site hematomas, one distal hand embolization and one transient cerebral ischemia). Two patients died within 30 days from other causes, and seven patients were lost to follow-up. Mean follow-up time was 16.7 months (range 0.3 to 68.2). Five patients had recurrent lesions treated by surgical (n = 2) or endovascular (n = 3) means. Cumulative primary patency rate was 91.7% and 77% at 12 and 24 months, respectively. Cumulative secondary patency rate was 96.5% and 91.7% at 12 and 24 months, respectively. Conclusion: Stenting of subclavian and innominate artery lesions resulted in immediate resolution of patients' symptoms with durable midterm effect and few complications in a larger patient group with serious comorbid conditions

Renal artery pulsatility index and renal volume: Normal fetuses versus growth-retarded fetuses

International Nuclear Information System (INIS)

Lee, Kyung Soon; Woo, Bock Hi

2001-01-01

To evaluate the blood flow velocity waveform of the renal artery and renal volume of growth-retarded fetuses and to compare them with those of normal fetuses. Pulsatility index of the renal artery and renal volume measured by three-dimensional ultrasonography were obtained from seventy eight normal fetuses at the gestational age from twenty five to thirty nine weeks and eighteen intrauterine growth retarded fetuses whose weight was below ten percentile at birth. We studied changes of the pulsatility index of the renal artery and renal volume according to the gestational age and compared with those of growth-retarded fetuses. Pulsatility index (PI) of the fetal renal artery decreased throughout the gestational period (r=0.703, p<0.0001). In growth-retarded fetuses, despite of abnormal doppler velocity waveform of the middle cerebral artery, which was showing fetal hypoxia, the renal PI was not increased significantly. The fetal renal volume increased throughout the gestational period (r=0.834, p<0.0001) whereas in growth-retarded fetuses, all renal volume was below fifth percentile of normal fetuses. In growth-retarded fetuses, fetal renal volume was decreased significantly without change of the renal vascular flow. Therefore, the fetal renal volume measured by three-dimensional ultrasonography may be a helpful parameter in the diagnosis of growth-retarded fetuses.

Renal artery pulsatility index and renal volume: Normal fetuses versus growth-retarded fetuses

Energy Technology Data Exchange (ETDEWEB)

Lee, Kyung Soon; Woo, Bock Hi [Ewha Womans University College of Medicine, Seoul (Korea, Republic of)

2001-06-15

To evaluate the blood flow velocity waveform of the renal artery and renal volume of growth-retarded fetuses and to compare them with those of normal fetuses. Pulsatility index of the renal artery and renal volume measured by three-dimensional ultrasonography were obtained from seventy eight normal fetuses at the gestational age from twenty five to thirty nine weeks and eighteen intrauterine growth retarded fetuses whose weight was below ten percentile at birth. We studied changes of the pulsatility index of the renal artery and renal volume according to the gestational age and compared with those of growth-retarded fetuses. Pulsatility index (PI) of the fetal renal artery decreased throughout the gestational period (r=0.703, p<0.0001). In growth-retarded fetuses, despite of abnormal doppler velocity waveform of the middle cerebral artery, which was showing fetal hypoxia, the renal PI was not increased significantly. The fetal renal volume increased throughout the gestational period (r=0.834, p<0.0001) whereas in growth-retarded fetuses, all renal volume was below fifth percentile of normal fetuses. In growth-retarded fetuses, fetal renal volume was decreased significantly without change of the renal vascular flow. Therefore, the fetal renal volume measured by three-dimensional ultrasonography may be a helpful parameter in the diagnosis of growth-retarded fetuses.

Treatment of non-neoplastic renal hemorrhage with segmental embolization of renal artery

International Nuclear Information System (INIS)

Zhu Bing

2007-01-01

Objective: To explore the value of segmental embolization of renal artery in dealing with non- neoplastic renal hemorrhage. Methods: Four cases of non-neoplastic hemorrhage, including 2 with bleeding after renal acupuncture biopsy, 2 with bleeding after nephrolithotomy and 1 with congenital renal arteriovenous malformation, were treated with superselective segmental embolization of renal artery. 2 were embolized with coil, 1 with alcohol plus coil and 1 with PVA parcels. Results: Hematuria disappeared in 1-3 days. There was no recurrence in 7-45 months follow up and no complications induced by embolization. Conclusion: It is a safe and reliable therapy to treat non-neoplastic renal hemorrhage with segmental embolization of renal artery. (authors)

Renal vein oxygen saturation in renal artery stenosis

DEFF Research Database (Denmark)

Nielsen, K; Rehling, M; Henriksen, Jens Henrik Sahl

1992-01-01

Renal vein oxygen-saturation was measured in 56 patients with arterial hypertension and unilateral stenosis or occlusion of the renal artery. Oxygen-saturation in blood from the ischaemic kidney (84.4%, range 73-93%) was significantly higher than that from the 'normal' contralateral kidney (81...... than its blood flow. This is probably due to decreased filtration fraction and filtered sodium with subsequent reduction in absolute tubular re-absorption of sodium ions....

Covered Stent and Coils Embolization of a Pulmonary Artery Pseudoaneurysm After Gunshot Wound

International Nuclear Information System (INIS)

Huet, Nicolas; Rodiere, Mathieu; Badet, Michel; Michoud, Marie; Brichon, Pierre-Yves; Ferretti, Gilbert; Thony, Frédéric

2016-01-01

We report the first case of endovascular covered stent implantation for the treatment of a large pulmonary artery pseudoaneurysm (PAPA) following a right thoracic gunshot wound. After resuscitation and hemodynamic stabilization, a CT angiography was performed to analyze the neck size of the PAPA and its position relative to the branches of the parent artery. Covered stent implantation with additional coil embolization was successfully performed. At the 4-year follow-up, the stents remained patent and there was neither pseudoaneurysm recurrence nor treatment-related complication.

Covered Stent and Coils Embolization of a Pulmonary Artery Pseudoaneurysm After Gunshot Wound

Energy Technology Data Exchange (ETDEWEB)

Huet, Nicolas, E-mail: nhuet@chu-grenoble.fr; Rodiere, Mathieu, E-mail: mrodiere@chu-grenoble.fr [Hôpital Universitaire de Grenoble and Université Grenoble Alpes, Department of Radiology and Medical Imaging (France); Badet, Michel, E-mail: michel.badet@ch-chambery.fr [Centre Hospitalier Métropôle Savoie, site de Chambéry, Intensive Care Unit (France); Michoud, Marie, E-mail: marie.michoud@ch-chambery.fr [Centre Hospitalier Métropôle Savoie, Site de Chambéry, Department of Radiology (France); Brichon, Pierre-Yves, E-mail: pybrichon@chu-grenoble.fr [Hôpital Universitaire de Grenoble and Université Grenoble Alpes, Department of Thoracic and Vascular Surgery (France); Ferretti, Gilbert, E-mail: gferretti@chu-grenoble.fr; Thony, Frédéric, E-mail: fthony@chu-grenoble.fr [Hôpital Universitaire de Grenoble and Université Grenoble Alpes, Department of Radiology and Medical Imaging (France)

2016-05-15

We report the first case of endovascular covered stent implantation for the treatment of a large pulmonary artery pseudoaneurysm (PAPA) following a right thoracic gunshot wound. After resuscitation and hemodynamic stabilization, a CT angiography was performed to analyze the neck size of the PAPA and its position relative to the branches of the parent artery. Covered stent implantation with additional coil embolization was successfully performed. At the 4-year follow-up, the stents remained patent and there was neither pseudoaneurysm recurrence nor treatment-related complication.

Angle change of the parent arteries after stent-assisted coil embolization of wide-necked intracranial bifurcation aneurysms

International Nuclear Information System (INIS)

Cho, W.-S.; Kang, H.-S.; Kim, J.E.; Kwon, O.-K.; Oh, C.W.; Cho, Y.D.; Han, M.H.

2014-01-01

Aim: To investigate the angle changes of the parent arteries after stent-assisted coil embolization of wide-necked intracranial bifurcation aneurysms. Materials and methods: The adjacent parent arterial angles before and after stent-assisted coil embolization were measured in 38 patients with aneurysms of the anterior communicating artery (ACoAA) and 41 patients with bifurcation aneurysms of the middle cerebral artery (MCABA). Variables were analysed in relation to the angle changes. Results: Vascular angles of the parent arteries significantly increased by 27.8° (±18.5°) immediately after stent-assisted coil embolization in 79 cases (p < 0.001), with 25.7° (±14.8°) in ACoAA and 29.7° (±21.4°) in MCABA, respectively. In 51 (64.6%) cases with follow-up angiography (mean interval 13.5 ± 4.1 months), vascular angles increased by 27.2° (±17.1°) immediately after treatment and further increased by 20.7° (±14.3°) at the last follow-up (all p < 0.001). More acute pre-stent angles of the parent arteries correlated with greater post-stent angle changes (p = 0.006). Younger age tended to be inversely related to post-stent angle changes (p = 0.091). Conclusion: Stent placement during coil embolization induced significant changes in the aneurysm–parent artery relationship. Further study is needed to elicit the association between angle change of the parent arteries and aneurysmal stability after coil embolization

Frequency and predictors of renal artery stenosis in patients with coronary artery disease

International Nuclear Information System (INIS)

Shah, S.S.; Hafeezullah, M.

2010-01-01

Background: Renal artery stenosis (RAS) is a common finding in patients undergoing coronary angiography. We designed this study to look for the frequency and any predictors of renal artery stenosis in patients with coronary artery disease (CAD). Methods: A total of 201 consecutive patients with CAD confirmed by coronary angiography underwent an abdominal aortogram in the same sitting to screen for RAS. Patient demographics and co-morbidities were analysed for any association with RAS. Results: Forty-one of the patients were female (20.4%); ninety patients were hypertensive (44.8%); 49 patients (24.4%) were smokers; 19 patients (9.5%) had renal insufficiency; 88 patients (43.8%) had high cholesterol levels; 44 patients (21.9%) were diabetic. Thirty-two patients (15.9%) had single coronary artery disease, 59 patients (29.4%) had two vessel disease, and 110 patients (54.7%) had three vessel disease. Significant renal artery stenosis (less or equal to 50% stenosis) was present in 26 patients (12.9%). Among the variables studied, only female gender was found to be associated with a higher frequency of renal artery stenosis (24.39% vs 10.0%, p=0.01). Conclusions: The frequency of renal artery stenosis in patients with coronary artery disease is 12.9%. Female gender is associated with a higher frequency of renal artery stenosis in patients with CAD. (author)

Multiple vascular anomalies involving renal, testicular and suprarenal arteries

Directory of Open Access Journals (Sweden)

Suresh Rao

2015-09-01

Full Text Available Knowledge of variations of blood vessels of the abdomen is important during operative, diagnostic and endovascular pro- cedures. During routine dissection of the abdominal cavity, we came across multiple vascular anomalies involving renal, suprarenal and testicular arteries. The left kidney was supplied by two renal arteries originating together from the abdomi- nal aorta, and the right kidney was supplied by two accessory renal arteries, one of which was arising from the right renal artery and the other one from the aorta (about 2 inches below the origin of the renal artery. Accessory renal veins were present on both sides. The right testicular artery was arising from the lower accessory renal artery. The left testicular artery was looping around the inferior tributary of the left renal vein, whereby forming a sharp kink. The left middle suprarenal artery was diving into three small branches; the upper two branches were supplying the left suprarenal gland, whereas the lower branch was supplying the left kidney. Furthermore, detailed literature and the clinical and surgical importance of the case are discussed. [Arch Clin Exp Surg 2015; 4(3.000: 168-171

Duplex ultrasound for identifying renal artery stenosis

DEFF Research Database (Denmark)

Zachrisson, Karin; Herlitz, Hans; Lönn, Lars

2017-01-01

Background Renal artery duplex ultrasound (RADUS) is an established method for diagnosis of renal artery stenosis (RAS), but there is no consensus regarding optimal RADUS criteria. Purpose To define optimal cutoff values for RADUS parameters when screening for RAS using intra-arterial trans...

Juxtarenal Modular Aortic Stent Graft Infection Caused by Staphylococcus aureus

Directory of Open Access Journals (Sweden)

Róbert Novotný

2016-01-01

Full Text Available Introduction. We are presenting a case report of an infected modular abdominal stent graft. Case Presentation. A 67-year-old male patient three years after Cook’s modular abdominal aortic aneurysm (AAA graft implantation for juxtarenal AAA with an implantation of a stent extension into the right common iliac artery for type Ib endoleak. The patient was admitted into our center in severe condition with suspected retroperitoneal bleeding. Computed tomography angiography (CTAG confirmed retroperitoneal bleeding in the right common iliac artery. An urgent surgical revision was indicated; destructed arterial wall around the stent extension in the right common iliac artery was discovered. Due to the severe state of health of the patient, a resection of the infected stent and affected arterial wall was performed, followed by an iliac-femoral crossover bypass. The patient was transported to the intensive care unit with hepatic and renal failure, with maximal catecholamine support. Combined antibiotic treatment was started. The patient died five hours after the procedure. The cause of death was multiorgan failure caused by sepsis. Hemocultures and perioperative microbiological cultures showed the infection agent to be Staphylococcus aureus methicillin sensitive. Conclusion. Stent graft infection is a rare complication. Treatment is associated with high mortality and morbidity.

Efficacy of stent angioplasty for symptomatic stenoses of the proximal vertebral artery

Energy Technology Data Exchange (ETDEWEB)

Weber, W. [Department of Radiology and Neuroradiology, Alfried Krupp Hospital, Essen (Germany); Mayer, T.E. [Department of Neuroradiology, Klinikum Grosshadern, University of Munich (Germany); Henkes, H. [Department of Radiology and Neuroradiology, Alfried Krupp Hospital, Essen (Germany); Kis, B. [Department of Neurology, Alfried Krupp Hospital, Essen (Germany) and Department of Psychiatry and Psychotherapy, University of Duisburg-Essen, Virchow Street 174, D-45147 Essen (Germany)]. E-mail: bernhard.kis@uni-duisburg-essen.de; Hamann, G.F. [Department of Neurology, Klinikum Grosshadern, University of Munich (Germany); Holtmannspoetter, M. [Department of Neuroradiology, Klinikum Grosshadern, University of Munich (Germany); Brueckmann, H. [Department of Neuroradiology, Klinikum Grosshadern, University of Munich (Germany); Kuehne, D. [Department of Radiology and Neuroradiology, Alfried Krupp Hospital, Essen (Germany)

2005-11-01

Background: To evaluate the safety and efficacy of stent angioplasty in the treatment of symptomatic arteriosclerotic stenoses of the proximal vertebral artery (VA). Methods: Thirty-eight symptomatic stenoses of the vertebral origin were treated with flexible balloon-expandable coronary stents. Angiographic and clinical follow-up examinations were obtained in 26 patients at a mean of 11 months. Results: The immediate post-procedural angiographic results showed no residual stenosis in 33 vessels and mild residual stenoses in five vessels. Periprocedurally, there were two asymptomatic technical complications and one TIA. During follow-up re-stenosis could be detected in 10 cases (36%), and vessel occlusions in two patients. Two stents were broken. One of the restenosis caused a TIA within the follow-up period. Conclusions: Flexible balloon-expandable coronary stents proved to be save and effective in preventing vertebrobasilar stroke but were incapable to preserve the proximal vertebral artery lumen. For the VA origine an adequate stent, self-expanding, bioresorbable, or drug-eluting has to be found.

Efficacy of stent angioplasty for symptomatic stenoses of the proximal vertebral artery

International Nuclear Information System (INIS)

Weber, W.; Mayer, T.E.; Henkes, H.; Kis, B.; Hamann, G.F.; Holtmannspoetter, M.; Brueckmann, H.; Kuehne, D.

2005-01-01

Background: To evaluate the safety and efficacy of stent angioplasty in the treatment of symptomatic arteriosclerotic stenoses of the proximal vertebral artery (VA). Methods: Thirty-eight symptomatic stenoses of the vertebral origin were treated with flexible balloon-expandable coronary stents. Angiographic and clinical follow-up examinations were obtained in 26 patients at a mean of 11 months. Results: The immediate post-procedural angiographic results showed no residual stenosis in 33 vessels and mild residual stenoses in five vessels. Periprocedurally, there were two asymptomatic technical complications and one TIA. During follow-up re-stenosis could be detected in 10 cases (36%), and vessel occlusions in two patients. Two stents were broken. One of the restenosis caused a TIA within the follow-up period. Conclusions: Flexible balloon-expandable coronary stents proved to be save and effective in preventing vertebrobasilar stroke but were incapable to preserve the proximal vertebral artery lumen. For the VA origine an adequate stent, self-expanding, bioresorbable, or drug-eluting has to be found

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

Science.gov (United States)

Shida, Takuya; Umezu, Mitsuo; Iwasaki, Kiyotaka

2018-06-01

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

Management of Renal Artery Stenosis - an Update | Alhadad ...

African Journals Online (AJOL)

The role of the renal vasculature in eliciting renovascular hypertension (RVH) was established in 1934, when Goldblatt et al. [1] in a classical experimental study demonstrated that partial obstruction of the renal artery increased mean arterial blood pressure (BP). The pathophysiology of renal artery stenosis (RAS) is ...

Pancreatitis-Associated Splenic Artery Pseudoaneurysm: Endovascular Treatment with Self-Expandable Stent-Grafts

International Nuclear Information System (INIS)

Brountzos, Elias N.; Vagenas, Kostantinos; Apostolopoulou, Sotiria C.; Panagiotou, Irene; Lymberopoulou, Dimitra; Kelekis, Dimitrios A.

2003-01-01

We present a patient with a splenic arterypseudoaneurysm (SAPA) treated with placement of self-expandable stent-grafts. The procedure was complicated by stent-graft migration,but successful management resulted in lasting exclusion of the SAPA,while the patency of the splenic artery was preserved. This is the first report of self-expandable stent-graft treatment of SAPA

The Influence of Positioning of the Nellix Endovascular Aneurysm Sealing System on Suprarenal and Renal Flow: An In Vitro Study.

Science.gov (United States)

Boersen, Johannes T; Groot Jebbink, Erik; Van de Velde, Lennart; Versluis, Michel; Lajoinie, Guillaume; Slump, Cornelius H; de Vries, Jean-Paul P M; Reijnen, Michel M P J

2017-10-01

To examine the influence of device positioning and infrarenal neck diameter on flow patterns in the Nellix endovascular aneurysm sealing (EVAS) system. The transition of the aortic flow lumen into two 10-mm-diameter stents after EVAS creates a mismatched area. Flow recirculation may affect local wall shear stress (WSS) profiles and residence time associated with atherosclerosis and thrombosis. To examine these issues, 7 abdominal aortic aneurysm flow phantoms were created, including 3 unstented controls and 3 stented models with infrarenal neck diameters of 24, 28, and 32 mm. Stents were positioned within the instructions for use (IFU). Another 28-mm model was created to evaluate lower positioning of the stents outside the IFU (28-mm LP). Flow was visualized using optical particle imaging velocimetry (PIV) and quantified by time-averaged WSS (TAWSS), oscillatory shear index (OSI), and relative residence time (RRT) in the aorta at the anteroposterior (AP) midplane, lateral midplane, and renal artery AP midplane levels. Flow in the aorta AP midplane was similar in all models. Vortices were observed in the stented models in the lateral midplane near the anterior and posterior walls. In the 32-mm IFU and 28-mm LP models, a steady state of vortices appeared, with varying location during a cycle. In all models, a low TAWSS (OSI of 0.5 and peak RRT of 10 4 Pa -1 . This region was more proximally located in the stented models. The 24- and 28-mm IFU models showed flow with a higher velocity at the renal artery inflow compared to controls. TAWSS in the renal artery was lower near the orifice in all models, with the largest area in the 24-mm IFU model. OSI and RRT in the renal artery were near zero for all models. EVAS enhances vorticity proximal to the seal zone, especially with lower positioning of the device and in larger neck diameters. Endobags just below the renal artery affect the flow profile in a minor area of this artery in 24- and 28-mm necks, while lower stent

Conformally integrated stent cell resonators for wireless monitoring of peripheral artery disease

KAUST Repository

Viswanath, Anupam; Green, Scott Ryan; Kosel, Jü rgen; Gianchandani, Yogesh B.

2013-01-01

This paper presents the design and in vitro evaluation of magnetoelastic sensors intended for wireless monitoring of tissue accumulation in peripheral artery stents. The sensors, shaped like stent cells, are fabricated from 28-μm thick foils

Percutaneous stenting of the superior mesenteric artery for the treatment of chronic mesenteric ischemia

International Nuclear Information System (INIS)

Gweon, Hye Mi; Suh, Sang Hyun; Won, Jong Yun; Lee, Do Yun; Kim, Sam Soo

2008-01-01

We wanted to evaluate the effectiveness of stent placement on the superior mesenteric artery as a treatment for chronic mesenteric ischemia. Seven patients (mean age: 55 years, age range: 43-66 years) with chronic mesenteric ischemia were enrolled between March 2000 and September 2003. All the patients underwent pre-procedure contrast enhanced computerized tomography to evaluate for occlusion or stenosis of the mesenteric arteries and they then underwent an angiographic procedure. A balloon-expandable metal stent was placed in the superior mesenteric artery, and this was combined with balloon angioplasty and thrombolysis. We evaluated the angiographic and procedural success after the procedures. Angiographic and procedural success was obtained in 100% of the patients and the clinical symptoms improved in 100% of the patients. The patency at 6-months and 1-year was 85% and 71%, respectively. The mean follow-up period was 12 months (range: 1-25 months). During the follow-up period, ischemic symptoms recurred in 2 patients, and restenosis in a stent was confirmed with angiography; one patient was successfully treated by stent placement in the celiac artery and the other patient died due to extensive mesenteric thrombosis. For the treatment of chronic mesenteric ischemia, percutaneous stent placement on the superior mesenteric artery showed a favorable result and it was an effective alternative to surgery for the high-risk patients

Clinical experience of cerebral protection with balloon occlusion during carotid artery stenting

International Nuclear Information System (INIS)

Jaeger, H.J.; Mathias, K.D.; Drescher, R.; Bockisch, G.; Hauth, E.; Demirel, E.; Gissler, H.M.; Witten/Herdecke Univ.

2001-01-01

Purpose: To asses the technical feasibility and the results of cerebral protection with the GuardWire Plus Temporary Occlusion and Aspiration System during carotid artery stenting for high-grade stenosis. Patients and Methods: In 20 patients 20 carotid artery stenoses were treated with stent placement under cerebral protection. A contralateral carotid occlusion was an exclusion criteria for the use of the protection device. In all cases only aspiration, but no flushing was used before deflation of the occlusion balloon. In 17 of 20 patients diffusion-weighted (DW-)MRT imaging of the brain was performed before and 24 hours after the procedure. Results: The stent implantation was successfully performed in all patients. In 3 patients neurologic symptoms occurred during the occlusion time. In these 3 patients the symptoms immediately disappeared after deflation of the balloon. In one case there was dilatation of the internal carotid artery at the site of the balloon inflation. In 3 of the 17 DW-MR images new ipsilateral cerebral lesions, in one case a new contralateral lesion occurred after the procedure. Conclusions: The cerebral protection procedure is technically feasible. The occlusion of the internal carotid artery was not tolerated by all patients. The DW-MR imaging demonstrated cerebral lesions indicating the occurrence of cerebral microemboli during the procedure. Further investigations are necessary to determine if the use of the cerebral protection device will improve the results of the carotid artery stenting for high-grade stenoses. (orig.) [de

MR angiography and the preoperative evaluation of renal arteries

International Nuclear Information System (INIS)

Nakahara, Kimitoshi; Yokoyama, Hiroshi; Tsuji, Yuji

2001-01-01

To determine the accuracy of gadolinium-enhanced, three-dimensional, magnetic resonance angiography (3D-MRA) in the visualization of the arterial anatomy of the kidney, we compared preoperative 3D-MRA results with surgical findings in 37 patients who underwent renal surgery. 3D-MRA findings were confirmed surgically in 30 of these patients (81%). However, 4 of 7 accessory renal arteries were missed by this imaging technique. Furthermore, 3D-MRA failed to visualize renal arteries in all of the three atrophic kidneys. 3D-MRA is a safe and reliable procedure for the preoperative evaluation of renal arteries. However, the depiction of smaller renal arteries, such as accessory and atrophic arteries, is less accurate. (author)

MR angiography and the preoperative evaluation of renal arteries

Energy Technology Data Exchange (ETDEWEB)

Nakahara, Kimitoshi; Yokoyama, Hiroshi; Tsuji, Yuji [Fukuoka Univ. (Japan). School of Medicine

2001-04-01

To determine the accuracy of gadolinium-enhanced, three-dimensional, magnetic resonance angiography (3D-MRA) in the visualization of the arterial anatomy of the kidney, we compared preoperative 3D-MRA results with surgical findings in 37 patients who underwent renal surgery. 3D-MRA findings were confirmed surgically in 30 of these patients (81%). However, 4 of 7 accessory renal arteries were missed by this imaging technique. Furthermore, 3D-MRA failed to visualize renal arteries in all of the three atrophic kidneys. 3D-MRA is a safe and reliable procedure for the preoperative evaluation of renal arteries. However, the depiction of smaller renal arteries, such as accessory and atrophic arteries, is less accurate. (author)

Renal sympathetic denervation: MDCT evaluation of the renal arteries.

LENUS (Irish Health Repository)

Hutchinson, Barry D

2013-08-01

Percutaneous transluminal renal sympathetic denervation is a new treatment of refractory systemic hypertension. The purpose of this study was to assess the clinical utility of MDCT to evaluate the anatomic configuration of the renal arteries in the context of renal sympathetic denervation.

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

International Nuclear Information System (INIS)

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

2001-01-01

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

Complications in percutaneous transluminal stenting for carotid artery stenosis

International Nuclear Information System (INIS)

Li Shenmao; Miao Zhongrong; Zhu Fengshui; Ji Xunming; Jiao Liqun; Qi Jianshu; Ling Feng

2007-01-01

Objective: To discuss the complications of endovascular stenting for carotid artery stenosis. Methods: Cerebral vascular angiography and cervical Doppler sonography were performed in 648 patients with carotid artery stenosis. Emboli-protected device was used in 365 patients and none in 283 patients. Results: All 648 patients were technically successful (100%). Symptoms disappeared or improved in 78.7% patients. Slow heart rate during operation existed in 26.4% patients. Embolism caused by dislodgment of emboli occurred in 5 patients, 3 of them recovered after treatment and 2 had unilateral dyskinesias. Intracranial hemorrhage occurred in 3 patients. Stroke or death within 30 days after operation occurred in 6 patients(1.24%). 322 patients (77.8%)were followed up. Restenosis occurred in 17 patients(3.3%). Conclusion: Percutaneous transluminal stenting is a safe option for carotid artery stenosis. Correct evaluation of clinical and angiographic data before operation, together with normative manipulation and nursing during and after operation are the key points to avoid complications. (authors)

Accessory renal arteries: Prevalence in resistant hypertension and an important role in nonresponse to radiofrequency renal denervation

Energy Technology Data Exchange (ETDEWEB)

VonAchen, Paige [Minneapolis Heart Institute and Foundation at Abbott Northwestern Hospital, Minneapolis, MN (United States); Hamann, Jason [Boston Scientific Corporation, Maple Grove, MN (United States); Houghland, Thomas; Lesser, John R.; Wang, Yale; Caye, David; Rosenthal, Kristi; Garberich, Ross F. [Minneapolis Heart Institute and Foundation at Abbott Northwestern Hospital, Minneapolis, MN (United States); Daniels, Mary [Vital Images/Toshiba, Minnetonka, MN (United States); Schwartz, Robert S., E-mail: rss@rsschwartz.com [Minneapolis Heart Institute and Foundation at Abbott Northwestern Hospital, Minneapolis, MN (United States)

2016-10-15

Objective: The aim of this study was to understand the role of accessory renal arteries in resistant hypertension, and to establish their role in nonresponse to radiofrequency renal denervation (RDN) procedures. Background: Prior studies suggest a role for accessory renal arteries in hypertensive syndromes, and recent clinical trials of renal denervation report that these anomalies are highly prevalent in resistant hypertension. This study evaluated the relationships among resistant hypertension, accessory renal arteries, and the response to radiofrequency (RF) renal denervation. Methods: Computed Tomography Angiography (CTA) and magnetic resonance imaging (MRI) scans from 58 patients with resistant hypertension undergoing RF renal denervation (RDN) were evaluated. Results were compared with CT scans in 57 healthy, normotensive subjects undergoing screening as possible renal transplant donors. All scans were carefully studied for accessory renal arteries, and were correlated with long term blood pressure reduction. Results: Accessory renal arteries were markedly more prevalent in the hypertensive patients than normotensive renal donors (59% vs 32% respectively, p = 0.004). RDN had an overall nonresponse rate of 29% (response rate 71%). Patients without accessory vessels had a borderline higher response rate to RDN than those with at least one accessory vessel (83% vs 62% respectively, p = 0.076) and a higher RDN response than patients with untreated accessory arteries (83% vs 55%; p = 0.040). For accessory renal arteries and nonresponse, the sensitivity was 76%, specificity 49%, with positive and negative predictive values 38% and 83% respectively. Conclusions: Accessory renal arteries were markedly over-represented in resistant hypertensives compared with healthy controls. While not all patients with accessory arteries were nonresponders, nonresponse was related to both the presence and non-treatment of accessory arteries. Addressing accessory renal arteries in

Accessory renal arteries: Prevalence in resistant hypertension and an important role in nonresponse to radiofrequency renal denervation

International Nuclear Information System (INIS)

VonAchen, Paige; Hamann, Jason; Houghland, Thomas; Lesser, John R.; Wang, Yale; Caye, David; Rosenthal, Kristi; Garberich, Ross F.; Daniels, Mary; Schwartz, Robert S.

2016-01-01

Objective: The aim of this study was to understand the role of accessory renal arteries in resistant hypertension, and to establish their role in nonresponse to radiofrequency renal denervation (RDN) procedures. Background: Prior studies suggest a role for accessory renal arteries in hypertensive syndromes, and recent clinical trials of renal denervation report that these anomalies are highly prevalent in resistant hypertension. This study evaluated the relationships among resistant hypertension, accessory renal arteries, and the response to radiofrequency (RF) renal denervation. Methods: Computed Tomography Angiography (CTA) and magnetic resonance imaging (MRI) scans from 58 patients with resistant hypertension undergoing RF renal denervation (RDN) were evaluated. Results were compared with CT scans in 57 healthy, normotensive subjects undergoing screening as possible renal transplant donors. All scans were carefully studied for accessory renal arteries, and were correlated with long term blood pressure reduction. Results: Accessory renal arteries were markedly more prevalent in the hypertensive patients than normotensive renal donors (59% vs 32% respectively, p = 0.004). RDN had an overall nonresponse rate of 29% (response rate 71%). Patients without accessory vessels had a borderline higher response rate to RDN than those with at least one accessory vessel (83% vs 62% respectively, p = 0.076) and a higher RDN response than patients with untreated accessory arteries (83% vs 55%; p = 0.040). For accessory renal arteries and nonresponse, the sensitivity was 76%, specificity 49%, with positive and negative predictive values 38% and 83% respectively. Conclusions: Accessory renal arteries were markedly over-represented in resistant hypertensives compared with healthy controls. While not all patients with accessory arteries were nonresponders, nonresponse was related to both the presence and non-treatment of accessory arteries. Addressing accessory renal arteries in

Percutaneous subclavian artery stent-graft placement following failed ultrasound guided subclavian venous access

Directory of Open Access Journals (Sweden)

Szkup Peter

2006-05-01

Full Text Available Abstract Background Ultrasound guidance for central and peripheral venous access has been proven to improve success rates and reduce complications of venous cannulation. Appropriately trained and experienced operators add significantly to diminished patient morbidity related to venous access procedures. We discuss a patient who required an arterial stent-graft to prevent arterial hemorrhage following inadvertent cannulation of the proximal, ventral, right subclavian artery related to unsuccessful ultrasound guided access of the subclavian vein. Case presentation During pre-operative preparation for aortic valve replacement and aorto-coronary bypass surgery an anesthetist attempted ultrasound guided venous access. The ultrasound guided attempt to access the right jugular vein failed and the ultrasound guided attempt at accessing the subclavian vein resulted in inappropriate placement of an 8.5 F sheath in the arterial system. Following angiographic imaging and specialist consultations, an arterial stent-graft was deployed in the right subclavian artery rather than perform an extensive anterior chest wall resection and dissection to extract the arterial sheath. The patient tolerated the procedure, without complication, despite occlusion of the right internal mammary artery and the right vertebral artery. There were no neurologic sequelae. There was no evidence of hemorrhage after subclavian artery sheath extraction and stent-graft implantation. Conclusion The attempted ultrasound guided puncture of the subclavian vein resulted in placement of an 8.5 F subclavian artery catheter. Entry of the catheter into the proximal subclavian artery beneath the medial clavicle, the medial first rib and the manubrium suggests that the operator, most likely, did not directly visualize the puncture needle enter the vessel with the ultrasound. The bones of the anterior chest impede the ultrasound beam and the vessels in this area would not be visible to ultrasound

Orbital atherectomy as an adjunct to debulk difficult calcified lesions prior to mesenteric artery stenting.

Science.gov (United States)

Manunga, Jesse M; Oderich, Gustavo S

2012-08-01

To describe a technique in which percutaneous orbital atherectomy is used to debulk heavily calcified superior mesenteric artery (SMA) occlusions as an adjunct in patients undergoing angioplasty and stenting. The technique is demonstrated in a 62-year-old woman with a replaced right hepatic artery originating from an SMA occluded by densely calcified lesions. Via a left transbrachial approach, a 7-F MPA guide catheter was used to engage the ostium of the SMA, which was crossed using a catheter and guidewire. The calcified lesion was debulked using the 2-mm Diamondback 360° orbital atherectomy system. The wire was exchanged for a 0.014-inch filter wire and 0.018-inch guidewire. Using a 2-guidewire technique, the SMA was stented with a self-expanding stent for the distal lesion that crossed side branches and a balloon-expandable stent at the ostium. A 0.014-inch guidewire was placed into the replaced hepatic artery through a cell of the self-expanding stent, followed by deployment of a small balloon-expandable stent to address the residual lesion. The use of orbital atherectomy to debulk occluded and heavily calcified SMA lesions may optimize the technical results with angioplasty and stenting.

MR angiography of in situ and transplanted renal arteries

International Nuclear Information System (INIS)

Smith, H.J.; Bakke, S.J.

1993-01-01

Three-dimensional (3D) time-of-flight (TOF) MR angiography (MRA) was performed in 34 patients with suspected renal artery disease. In situ (i.e., nontransplanted) renal arteries were studied with MRA in 14 patients. Of these, 12 had conventional angiography for comparison. Twenty-four MRAs of transplanted renal arteries were obtained in 20 patients; 8 of these had angiography as well. Significant stenoses of in situ renal arteries were diagnosed with a sensitivity of 100% and a specificity of 95%. The stenoses were all proximal; 3D TOF MRA proved inadequate for depiction of peripheral renal arteries. MRA and angiography showed good agreement between findings in 7 of 8 patients with renal transplants. In one patient with a renal transplant, MRA showed a significant stenosis of the arterial anastomosis which appeared completely normal at i.a. DSA, indicating that findings at MRA still need to be confirmed by more established alternative methods. (orig.)

Percutaneous transluminal angioplasty and stent placement for iliofemoral arterial atherosclerotic occlusive disease

International Nuclear Information System (INIS)

Zheng Yanbo; Jiang Wenjin; Liu Sheng; Song Xuepeng; Sheng Qirui

2006-01-01

Objectives: To assess the safety and efficacy of percutaneous transluminal angioplasty (PTA) and stent placement for the treatment of iliofemoral arterial atherosclerotic occlusive diseases. Methods From April 1999 to August 2004, 13 cases of iliofemoral arterial occlusions were recanalized with contact thrombolytic therapy combined with guide wire mechanical recanalization method, followed by angioplasty and stent placement. A total of 25 self-expanding Wallstents were deployed. All patients were followed up by means of duplex ultrasound, angiography, or both. Results: All 13 cases were successfully recanalized, with technical successful rate of 100%. Available follow-up for all patients from 8 months-5 years (mean 26.2 months) included one patient undergoing again with successful contact thrombolysis because of early thrombosis; another patient with recurrent symptoms at 19 month after operation undertaking surgical bypass because of later reocclusion; all of the rest stents showing patency by the end of the study. Conclusions: Contact thrombolysis combined with guide wire mechanical recanalization for iliofemoral arterial occlusion is safe and effective, whereas PTA and stent placement would have the nearly same efficacy for the disease with mild injury and low restenosis. (authors)

High-dose external beam irradiation inhibits neointima formation in stented pig coronary arteries

International Nuclear Information System (INIS)

Verheye, Stefan; Coussement, Patrick K.; Salame, Mahomed Y.; Fallahi, Payam; Cui Jianhua; Chronos, Nicolas A.F.; King, Spencer B.; Crocker, Ian R.; Robinson, Keith A.

2001-01-01

Purpose: To evaluate high-dose external beam irradiation (EBRT) in a pig coronary stent preparation because low and intermediate-dose EBRT failed to show inhibition of neointima formation in stented animal models. Methods and Materials: Thirty-five stents were implanted in the coronary arteries of 17 pigs. Seven pigs were exposed to a single dose of 21 Gy EBRT immediately after stenting. Ten stented, nonirradiated pigs served as controls. After 4 weeks, the study arteries and myocardium were examined by light and scanning electron microscopy. Results: Compared with controls, 21 Gy EBRT resulted in a larger lumen area (7.57±1.67 mm 2 vs. 4.00±1.63 mm 2 , p 2 vs. 3.36±2.26 mm 2 , p<0.001) and a smaller maximal intimal thickness (0.16±0.09 mm vs. 0.68±0.31 mm, p<0.001). Unresorbed intramural hemorrhages and adherent mural thrombi were present in the irradiated vessels, which also showed incomplete re-endothelialization. The irradiated hearts demonstrated diffuse interstitial and perivascular inflammation and fibrosis. Conclusions: EBRT at 21 Gy to the entire heart significantly inhibited neointima formation in stented pig coronary arteries but also resulted in incomplete re-endothelialization, myocardial inflammation, and fibrosis. Improvements in localization and delivery techniques are required to allow clinical implementation of this technique

Wingspan stent for symptomatic M1 stenosis of middle cerebral artery

International Nuclear Information System (INIS)

Guo Xinbin; Ma Nan; Hu Xiaobo; Guan Sheng; Fan Yimu

2011-01-01

Objective: Stent placement for intracranial atherosclerotic stenosis has become an alternative treatment technique; however, stent placement for middle cerebral artery (MCA) stenosis remains a technical and clinical challenge. Our purpose was to assess the safety and feasibility of Wingspan stent for patients with symptomatic M1 stenosis, and its initial effect on prevention of ischemic events. Methods: Fifty-three cases with recurrent symptomatic MCA stenosis resistant to medical therapy treated by self-expanding stent were reviewed retrospectively (average 58 ± 18.5 years old, 19 women). All patients underwent angioplasty and stenting with the Gateway balloon–Wingspan stent system, and advised follow-up with DSA or TCD at 6th month. Results: Patients had an average stenosis ratio of 76.5 ± 15.4% prior to the treatment. Of the 53 patients, the technical success rate was 98.1% as a whole (52/53). The mean degree of stenosis reduced from (76.5 ± 15.4)% to (18.2 ± 11.3)%. Complications associated with the procedure include subarachnoid hemorrhage (1.89%) and occlusion (3.78%) occurred. During a follow-up of 6 months, there was no recurrence of transient ischemic attack or stroke in 52 cases with successful stenting. Cerebral hemodynamics of MCA using transcranial Doppler monitoring were at normal level (<120 cm/s) in 41 follow-up patients. The follow up angiography at 6 month post-procedure was conducted in 32 patients and showed good patency in stented vessels. Conclusions: Wingspan stent for symptomatic stenosis of middle cerebral artery is a safe and feasible procedure. It improves clinical outcome in the intermediate follow up, but its long-term effect remains to be further evaluated.

Coronary artery stent mimicking intracardiac thrombus on cardiac magnetic resonance imaging due to signal loss

DEFF Research Database (Denmark)

Qayyum, Abbas Ali; Vejlstrup, Niels Grove; Ahtarovski, Kiril Aleksov

2012-01-01

Since the introduction of percutaneous coronary intervention for coronary artery disease, thousands of patients have been treated with the implantation of coronary stents. Moreover, several of the patients with coronary stent undergo cardiac magnetic resonance (CMR) imaging every year. This case...... report is of a 77-year-old man who was previously treated with the implantation of a coronary stent in the left circumflex artery. He underwent CMR imaging, which revealed a process 14×21 mm in the left atrium. Cardiac contrast computed tomography did not demonstrate any cardiac pathology. While...... the signal loss on MRI associated with implanted metallic devices is known, we report a case where an implanted coronary stent in the left circumflex artery led to an intracardiac signal loss mimicking intracardiac thrombus/tumor....

Renal artery stenosis: comparative assessment by unenhanced renal artery mra versus contrast-enhanced MRA

International Nuclear Information System (INIS)

Khoo, Michael M.Y.; Deeab, Dhafer; Gedroyc, Wladyslaw M.W.; Dick, Elizabeth A.; Duncan, Neil; Taube, David

2011-01-01

To evaluate steady-state free precession (SSFP) non-contrast-enhanced MR angiography (Unenhanced-MRA) versus conventional contrast-enhanced MR angiography (CE-MRA) in the detection of renal artery stenosis (RAS). Retrospective analysis of 70 consecutive patients referred for suspected RAS, examined by SSFP Unenhanced-MRA and CE-MRA. Image quality, quality of visible renal arterial segments, presence and grade of RAS were evaluated. The Unenhanced-MRA were compared against reference standard CE-MRA results. 149 renal arteries were assessed with 21 haemodynamically significant stenoses (≥50% stenosis) demonstrated by CE-MRA. Combined sensitivity and specificity for RAS detection by Unenhanced-MRA was 72.8% and 97.8% respectively. There is substantial correlation for RAS detection between Unenhanced-MRA and CE-MRA with kappa values of between 0.64 and 0.74. There was excellent inter-observer correlation for RAS on Unenhanced-MRA (kappa values 0.82-1.0). Our study has shown Unenhanced-MRA to be a viable alternative to CE-MRA, yielding images equal in quality without the requirement for gadolinium contrast agents. The sensitivity and specificity for the detection of haemodynamically significant stenoses are comparable to CE-MRA. Potentially, Unenhanced-MRA could be used as an initial investigation to avoid performing CE-MRA in patients with normal renal arteries, however we suggest that its real value will lie in being complementary to CE-MRA. (orig.)

Follow-up of renal and mesenteric artery revascularization with duplex ultrasonography

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Taylor, David C.; Houston, Gordon T.M.; Anderson, Caroline; Jameson, Margot; Popatia, Shelley

1996-01-01

Objective To evaluate the long-term anatomic results of renal revascularization procedures using duplex ultrasonography. Design A case series. Setting A university-affiliated hospital. Patients Twenty-five patients who had undergone renal percutaneous transluminal angioplasty (PTA) (18 arteries), renal bypass (10 arteries) and mesenteric bypass (6 arteries). The mean follow-up was 22 months (range from 3 to 48 months) for those who underwent renal PTA, 23 months (range from 1.5 to 70 months) for those who underwent renal bypass and 34 months (range from 8 to 144 months) for those who underwent mesenteric bypass. Main Outcome Measures Patency rates for the three procedures as assessed by duplex ultrasonography. Results Duplex ultrasonography demonstrated patency without stenosis after renal and mesenteric artery revascularization in 14 arteries subjected to renal PTA, 9 arteries subjected to renal bypass and 6 arteries subjected to mesenteric bypass. Three arteries that had renal PTA had recurrent vessel stenosis and one had occlusion. One artery that had renal bypass showed occlusion. Conclusions Renal PTA, renal bypass and mesenteric bypass are durable procedures at 2 years of follow-up, and duplex ultrasonography is a valuable method for assessing the patency of arteries after renal and mesenteric revascularization. PMID:8599785

Intravascular stenting in the superior mesenteric artery for chronic abdominal angina.

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Busquet, J

1997-11-01

Abdominal angina is an early clinical expression of occlusive mesenteric arterial insufficiency, a condition that requires aggressive treatment to prevent intestinal infarction. We report a case of chronic mesenteric ischemia in a young polyvascular man who had symptoms of abdominal angina. An aortic angiogram revealed a significant ostial stenosis of the superior mesenteric artery (SMA) associated with an occlusion of the inferior mesenteric artery. After predilation of the ostial portion of the SMA, significant residual stenosis remained. A balloon-expandable Palmaz P154 stent was deployed, restoring adequate luminal dimensions and blood flow. The patient was discharged after 2 days and remains asymptomatic at 5 months. Intraluminal stenting for treatment of mesenteric ischemia represents a viable alternative to surgical revascularization in selected cases.

Second generation drug-eluting stents versus bare-metal stents for percutaneous coronary intervention of the proximal left anterior descending artery

DEFF Research Database (Denmark)

Mangione, Fernanda Marinho; Biering-Sørensen, Tor; Nochioka, Kotaro

2017-01-01

OBJECTIVES: To compare mid-term outcomes between patients undergoing proximal left anterior descending artery (LAD) percutaneous coronary intervention (PCI) with second generation drug-eluting stent (DES) or bare-metal stent (BMS). BACKGROUND: PCI with BMS and first-generation DES have shown to b...

Acute renal haemodynamic and renin-angiotensin system responses to graded renal artery stenosis in the dog.

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Anderson, W P; Johnston, C I; Korner, P I

1979-01-01

1. The acute renal haemodynamic and renin-angiotensin system responses to graded renal artery stenosis were studied in chronically instrumented, unanaesthetized dogs. 2. Stenosis was induced over 30 sec by inflation of a cuff around the renal artery to lower distal pressure to 60, 40 or 20 mmHg, with stenosis maintained for 1 hr. This resulted in an immediate fall in renal vascular resistance, but over the next 5--30 min both resistance and renal artery pressure were restored back towards prestenosis values. Only transient increases in systemic arterial blood pressure and plasma renin and angiotensin levels were seen with the two milder stenoses. Despite restoration of renal artery pressure, renal blood flow remained reduced at all grades of stenosis. 3. Pre-treatment with angiotensin I converting enzyme inhibitor or sarosine1, isoleucone8 angiotensin II greatly attenuated or abolished the restoration of renal artery pressure and renal vascular resistance after stenosis, and plasma renin and angiotensin II levels remained high. Renal dilatation was indefinitely maintained, but the normal restoration of resistance and pressure could be simulated by infusing angiotensin II into the renal artery. 4. The effective resistance to blood flow by the stenosis did not remain constant but varied with changes in the renal vascular resistance. PMID:219182

The outcome of extracorporeal shockwave lithotripsy for renal pelvic stone with and without JJ stent--a comparative study.

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Mohayuddin, Nazim; Malik, Hamad Afzal; Hussain, Manzoor; Tipu, Salman Ahmed; Shehzad, Asad; Hashmi, Altaf; Naqvi, Syed Ali Anwar; Rizvi, Syed Adibul Hasan

2009-03-01

To compare the outcome of Extra corporeal shockwave lithotripsy for a renal pelvic stone with and without JJ stent. A comparative cross sectional study was carried out at Sindh Institute of Urology and Transplantation from January 2007 to January 2008. Eighty patients with renal pelvic stone measuring 2cm +/- 2mm were selected for treatment with Extra Corporeal Shockwave Lithotripsy (ESWL). All of these patients were adults with normal renal function and had unilateral renal stones with negative urine cultures. Patients with renal failure and children were excluded. They were divided into two groups of 40 each. Group A patients underwent ESWL without a JJ stent and in Group B a JJ stent was placed before ESWL. SLX F2 electromagnetic ESWL machine was used to impart shock waves. 3000 shockwaves were given in a session. Both the groups were compared for renal colic, steinstrasse, fever, lower urinary tract symptoms (LUTS) emergency room visits and hospital admissions, stone clearance, number of ESWL sessions, auxilliary procedures, (percutaneous nephrostomy or ureterorenoscopy) and cost. Ureteric colic occurred in 13 (32.5%) patients in group A and in 3 (7.5%) patient in group B. Steinstrasse developed in 4 (10%) patients with out JJ stent and in 3 (7.5%) patients with JJ stent. Fever was encountered in 1 (2.5%) patient in group A and in 3 (7.5%) patient in group B. Mean emergency room visits were 2.1 per patient in group A and 0.7 per patient in group B. Stone clearance occurred in 33 (82.5%) patients in group A and 31 (77.5%) in group B. In group B lower urinary tract symptoms were found in 50% versus 20% in group A. Auxillary procedure was performed in one (2.5%) patient each in both groups. Pre ESWL JJ stenting for a 2 cm +/- 2 mm renal stone was not beneficial in terms of steinstrasse, fever, stone clearance and number of ESWL sessions. However ureteric colic was significantly less in the stented group. Lower urinary tract symptoms (LUTS) was also significantly

Renal artery and parenchymal changes after renal denervation: assessment by magnetic resonance angiography

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Sanders, Margreet F.; Vink, Eva E.; Blankestijn, Peter J. [University Medical Center Utrecht, Department of Nephrology and Hypertension, PO Box 85500, Utrecht (Netherlands); Doormaal, Pieter Jan van; Habets, Jesse; Vonken, Evert-Jan; Leiner, Tim [University Medical Center Utrecht, Department of Radiology, Utrecht (Netherlands); Beeftink, Martine M.A.; Verloop, Willemien L.; Voskuil, Michiel [University Medical Center Utrecht, Department of Cardiology, Utrecht (Netherlands); Bots, Michiel L. [University Medical Center Utrecht, Julius Center for Health Sciences and Primary Care, Utrecht (Netherlands); Fadl Elmula, Fadl Elmula M. [Oslo University Hospital, Department of Internal Medicine and Department of Cardiology, Ullevaal, Oslo (Norway); Hammer, Frank [Cliniques Universitaires Saint-Luc, Universite Catholique de Louvain, Department of Radiology, Brussels (Belgium); Hoffmann, Pavel [Oslo University Hospital, Section for Interventional Cardiology, Department of Cardiology, Ullevaal, Oslo (Norway); Jacobs, Lotte; Staessen, Jan A. [University of Leuven, Studies Coordinating Centre, Research Unit Hypertension and Cardiovascular Epidemiology, KU Leuven Department of Cardiovascular Sciences, Leuven (Belgium); Mark, Patrick B.; Taylor, Alison H. [University of Glasgow, Institute of Cardiovascular and Medical Sciences, Glasgow, Scotland (United Kingdom); Persu, Alexandre; Renkin, Jean [Universite Catholique de Louvain, Pole of Cardiovascular Research, Institut de Recherche Experimentale et Clinique, Brussels (Belgium); Cliniques Universitaires Saint-Luc, Universite Catholique de Louvain, Cardiology Department, Brussels (Belgium); Roditi, Giles [Glasgow Royal Infirmary, Department of Radiology, Glasgow (United Kingdom); Spiering, Wilko [University Medical Centre Utrecht, Department of Vascular Medicine, Utrecht (Netherlands); Collaboration: on behalf of the European Network COordinating research on Renal Denervation (ENCOReD) Consortium

2017-09-15

Relatively little is known about the incidence of long-term renal damage after renal denervation (RDN), a potential new treatment for hypertension. In this study the incidence of renal artery and parenchymal changes, assessed with contrast-enhanced magnetic resonance angiography (MRA) after RDN, is investigated. This study is an initiative of ENCOReD, a collaboration of hypertension expert centres. Patients in whom an MRA was performed before and after RDN were included. Scans were evaluated by two independent, blinded radiologists. Primary outcome was the change in renal artery morphology and parenchyma. MRAs from 96 patients were analysed. Before RDN, 41 renal anomalies were observed, of which 29 mostly mild renal artery stenoses. After a median time of 366 days post RDN, MRA showed a new stenosis (25-49% lumen reduction) in two patients and progression of pre-existing lumen reduction in a single patient. No other renal changes were observed and renal function remained stable. We observed new or progressed renal artery stenosis in three out of 96 patients, after a median time of 12 months post RDN (3.1%). Procedural angiographies showed that ablations were applied near the observed stenosis in only one of the three patients. (orig.)

Valve-Like and Protruding Calcified Intimal Flap Complicating Common Iliac Arteries Kissing Stenting

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George S. Georgiadis

2015-01-01

Full Text Available Endovascular therapy for iliac artery chronic total occlusions is nowadays associated with low rates of procedure-related complications and improved clinical outcomes, and it is predominantly used as first-line therapy prior to aortobifemoral bypass grafting. Herein, we describe the case of a patient presenting with an ischemic left foot digit ulcer and suffering complex aortoiliac lesions, who received common iliac arteries kissing stents, illustrating at final antegrade and retrograde angiograms the early recognition of a blood flow obstructing valve-like calcified intimal flap protruding through the stent struts, which was obstructing antegrade but not retrograde unilateral iliac arterial axis blood flow. The problem was resolved by reconstructing the aortic bifurcation at a more proximal level. Completion angiogram verified normal patency of aorta and iliac vessels. Additionally, a severe left femoral bifurcation stenosis was also corrected by endarterectomy-arterioplasty with a bovine patch. Postintervention ankle brachial pressure indices were significantly improved. At the 6-month and 2-year follow-up, normal peripheral pulses were still reported without intermittent claudication suggesting the durability of the procedure. Through stent-protruding calcified intimal flap, is a very rare, but existing source of antegrade blood flow obstruction after common iliac arteries kissing stents.

Renal artery anatomy affects the blood pressure response to renal denervation in patients with resistant hypertension.

Science.gov (United States)

Hering, Dagmara; Marusic, Petra; Walton, Antony S; Duval, Jacqueline; Lee, Rebecca; Sata, Yusuke; Krum, Henry; Lambert, Elisabeth; Peter, Karlheinz; Head, Geoff; Lambert, Gavin; Esler, Murray D; Schlaich, Markus P

2016-01-01

Renal denervation (RDN) has been shown to reduce blood pressure (BP), muscle sympathetic nerve activity (MSNA) and target organ damage in patients with resistant hypertension (RH) and bilateral single renal arteries. The safety and efficacy of RDN in patients with multiple renal arteries remains unclear. We measured office and 24-hour BP at baseline, 3 and 6 months following RDN in 91 patients with RH, including 65 patients with single renal arteries bilaterally (group 1), 16 patients with dual renal arteries on either one or both sides (group 2) and 10 patients with other anatomical constellations or structural abnormalities (group 3). Thirty nine out of 91 patients completed MSNA at baseline and follow-up. RDN significantly reduced office and daytime SBP in group 1 at both 3 and 6 months follow-up (Pkidney function in any group. While RDN can be performed safely irrespective of the underlying renal anatomy, the presence of single renal arteries with or without structural abnormalities is associated with a more pronounced BP and MSNA lowering effect than the presence of dual renal arteries in patients with RH. However, when patients with dual renal arteries received renal nerve ablation in all arteries there was trend towards a greater BP reduction. Insufficient renal sympathetic nerve ablation may account for these differences. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Drug-eluting stent implantation for the percutaneous treatment of vertebro-basilar arterial stenosis

International Nuclear Information System (INIS)

Ma Rujun; Liu Jianmin; Huang Haiqing; Hong Bo; Xu Yi; Zhao Wenyuan; Zhao Rui; Chen Jun

2006-01-01

Objective: To evaluate the early results and mid-term outcomes following angioplasty of vertebro-basilar arterial stenosis with drug-eluting stents. Methods: All of the patients presented with recurrent TIA or ceretral infarction with >50% stenoses in vertebro-basilar arteries, and having failure in maximal medical therapy. All of the lesions were treated with primary stenting under local or general anesthesia and followed by continual anticoagulant therapy of clopidogrel and aspirin together with clinical follow-up and vascular imagings. Results: Of 28 stenoses (27 patients), 27 lesions were successfully treated with implantation of 24 Cypher stents, 2 Taxus stents and one Firebird stent. The mean stenotic severity reduced from (74 ± 6.7)% to (8.7 ± 4.4)%. Two patients had inchemic events relating to penetration vascular obstruction. During 2-14 months follow-up, the patients were clinically asymptomatic with no recurrent TIA/stoke. Angiographic follow-up was obtained in 14 patients at a mean of 7.2 months. Proximal restenosis (<50%) occurred in one patient (3.3%), and corrected with restenting, while others were free of intra-stent restenoses. Conclusion: Using DES in cerebrovascular stenosis is safe and effective with lowing the risk of intra-stent restenosis in comparison with bare stent. Further study for long term efficiency is still in need. (authors)

Carotid Artery Stenting Successfully Prevents Progressive Stroke Due to Mobile Plaque

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Masahiro Oomura

2015-05-01

Full Text Available We report a case of progressive ischemic stroke due to a mobile plaque, in which carotid artery stenting successfully prevented further infarctions. A 78-year-old man developed acute multiple infarcts in the right hemisphere, and a duplex ultrasound showed a mobile plaque involving the bifurcation of the left common carotid artery. Maximal medical therapy failed to prevent further infarcts, and the number of infarcts increased with his neurological deterioration. Our present case suggests that the deployment of a closed-cell stent is effective to prevent the progression of the ischemic stroke due to the mobile plaque.

Renal artery anatomy assessed by quantitative analysis of selective renal angiography in 1,000 patients with hypertension.

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Lauder, Lucas; Ewen, Sebastian; Tzafriri, Abraham Rami; Edelman, Elazer Reuven; Lüscher, Thomas Felix; Blankenstijn, Peter J; Dörr, Oliver; Schlaich, Markus; Sharif, Faisal; Voskuil, Michiel; Zeller, Thomas; Ukena, Christian; Scheller, Bruno; Böhm, Michael; Mahfoud, Felix

2018-05-20

With increasing attention to renovascular causes and targets for hypertension there arises a critical need for more detailed knowledge of renal arterial anatomy. However, a standardised nomenclature is lacking. The present study sought to develop a standardised nomenclature for renal anatomy considering the complexity and variation of the renal arterial tree and to assess the applicability of the nomenclature. One thousand hypertensive patients underwent invasive selective renal artery angiography in nine centres. Further, renovasography was performed in 249 healthy swine as a surrogate for normotensive anatomy. Anatomical parameters were assessed by quantitative vascular analysis. Patients' mean blood pressure was 168/90±26/17 mmHg. The right main renal artery was longer than the left (41±15 mm vs. 35±13 mm, prenal arteries and renal artery disease were documented in 22% and 9% of the patients, respectively. Other than exhibiting a longer left main renal artery in uncontrolled hypertensives (+2.7 mm, p=0.034) there was no anatomical difference between patients with controlled and uncontrolled hypertension. Main renal artery mean diameter was smaller in patients with impaired kidney function (GFR Renal arterial anatomy differs between sides but shows no difference between patients with and without blood pressure control. Impaired GFR was associated with small main renal artery diameter.

High-resolution ex vivo imaging of coronary artery stents using 64-slice computed tomography - initial experience

International Nuclear Information System (INIS)

Rist, Carsten; Nikolaou, Konstantin; Wintersperger, Bernd J.; Reiser, Maximilian F.; Becker, Christoph R.; Flohr, Thomas

2006-01-01

The aim of the study was to evaluate the potential of new-generation multi-slice computed tomography (CT) scanner technology for the delineation of coronary artery stents in an ex vivo setting. Nine stents of various diameters (seven stents 3 mm, two stents 2.5 mm) were implanted into the coronary arteries of ex vivo porcine hearts and filled with a mixture of an iodine-containing contrast agent. Specimens were scanned with a 16-slice CT (16SCT) machine; (Somatom Sensation 16, Siemens Medical Solutions), slice thickness 0.75 mm, and a 64-slice CT (64SCT, Somatom Sensation 64), slice-thickness 0.6 mm. Stent diameters as well as contrast densities were measured, on both the 16SCT and 64SCT images. No significant differences of CT densities were observed between the 16SCT and 64SCT images outside the stent lumen: 265±25HU and 254±16HU (P=0.33), respectively. CT densities derived from the 64SCT images and 16SCT images within the stent lumen were 367±36HU versus 402±28HU, P<0.05, respectively. Inner and outer stent diameters as measured from 16SCT and 64SCT images were 2.68±0.08 mm versus 2.81±0.07 mm and 3.29±0.06 mm versus 3.18±0.07 mm (P<0.05), respectively. The new 64SCT scanner proved to be superior in the ex vivo assessment of coronary artery stents to the conventional 16SCT machine. Increased spatial resolution allows for improved assessment of the coronary artery stent lumen. (orig.)

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

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

2017-09-01

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

Renal contrast-enhanced MR angiography: timing errors and accurate depiction of renal artery origins.

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Schmidt, Maria A; Morgan, Robert

2008-10-01

To investigate bolus timing artifacts that impair depiction of renal arteries at contrast material-enhanced magnetic resonance (MR) angiography and to determine the effect of contrast agent infusion rates on artifact generation. Renal contrast-enhanced MR angiography was simulated for a variety of infusion schemes, assuming both correct and incorrect timing between data acquisition and contrast agent injection. In addition, the ethics committee approved the retrospective evaluation of clinical breath-hold renal contrast-enhanced MR angiographic studies obtained with automated detection of contrast agent arrival. Twenty-two studies were evaluated for their ability to depict the origin of renal arteries in patent vessels and for any signs of timing errors. Simulations showed that a completely artifactual stenosis or an artifactual overestimation of an existing stenosis at the renal artery origin can be caused by timing errors of the order of 5 seconds in examinations performed with contrast agent infusion rates compatible with or higher than those of hand injections. Lower infusion rates make the studies more likely to accurately depict the origin of the renal arteries. In approximately one-third of all clinical examinations, different contrast agent uptake rates were detected on the left and right sides of the body, and thus allowed us to confirm that it is often impossible to optimize depiction of both renal arteries. In three renal arteries, a signal void was found at the origin in a patent vessel, and delayed contrast agent arrival was confirmed. Computer simulations and clinical examinations showed that timing errors impair the accurate depiction of renal artery origins. (c) RSNA, 2008.

Interventional Management of Delayed and Massive Hemobilia due to Arterial Erosion by Metallic Biliary Stent

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Jeong, Hee Seok [Dept. of Radiology, Gyeongsang National University Hospital, Jinju (Korea, Republic of); Shin, Tae Beom [Dept. of Diagnostic Radiology, Kimhae Jung Ang Hospital, Kimhae (Korea, Republic of); Hwang, Jae Cheol [Dept. of Radiology, Ulsan Hospital, Ulsan (Korea, Republic of); Bae, Jae Ik [Dept. of Radiology, Ajou University Hospital, Suwon (Korea, Republic of); Kim, Chang Won [Dept. of Radiology, Busan National University Hospital, Busan (Korea, Republic of)

2012-01-15

To evaluate the effectiveness of interventional management for delayed and massive hemobilia secondary to arterial erosion self expandable metallic stent (SES) in with biliary duct malignancy. Over 8-year period, eight patients who suffered from delayed massive hemobilia after SES placement for malignant biliary obstruction as palliative procedure, were included. The mean period between SES placement and presence of massive gastrointestinal hemorrhage was 66.5 days (15-152 days), pancreatic cancer (n = 2), Klatskin tumor (n = 2), common bile duct cancer (n = 2), intrahepatic cholangiocarcinoma (n = 1), and gastric cancer with ductal invasion (n = 1). Angiographic findings were pseudoaneurysm (n = 6), contrast extravasation (n = 1) and arterial spasm at segment (n = 1). Six patients underwent embolization of injured vessels using microcoils and N-butyl cyanoacrylate. Two patients underwent stent graft placement at right hepatic artery to prevent ischemic hepatic damage because of the presence of portal vein occlusion. Massive hemobilia was successfully controlled by the embolization of arteries (n = 6) and stent graft placement (n = 2) without related complications. The delayed massive hemobilia to arterial erosion metallic biliary stent is rare this complication be successfully treated by interventional management.

An experimental study on renal arterial and parenchymal change caused by selective renal infusion of epinephrine

International Nuclear Information System (INIS)

Jeon, Seok Chol; Yeon, Kyung Mo; Han, Man Chung

1981-01-01

Selective infusion of the epinephrine into the renal artery has been used in the field of the diagnostic and the therapeutic radiology for correct diagnosis and effective treatment, respectively. However, administration of overdose of epinephrine may cause serious complication, renal infarction. The study was undertaken to evaluate the sequential change of renal arterial constrictive effect of selective infusion of epinephrine into renal artery and to determine the critical doses of epinephrine producing irreversible renal infarct. A total of 25 rabbits are used, which are divided into 5 groups. Under the general anesthesia is made the selective infusion of various doses of epinephrine into the right renal artery of the rabbits. At the various time interval during and after the epinephrine infusion, renal angiography was done, and 24 hrs. later, gross and microscopic findings of the kidney were observed. The results are as follows; 1. Vasoconstriction of renal artery occurred within 2 mins. infusion, and maximum effect within 5 mins. 2. It seems that there is correlation between the amount of infused epinephrine and the time taken to recover from constriction of renal artery. 3. When epinephrine is infused into the renal artery in the rate of 1 ug/min., renal infarct is not noticed below the level of 10 mins., but correlation between the amount of infused epinephrine and the frequency of renal infarct occurs above 20 mins. infusion

Stenting for peripheral artery disease of the lower extremities: an evidence-based analysis.

Science.gov (United States)

2010-01-01

In January 2010, the Medical Advisory Secretariat received an application from University Health Network to provide an evidentiary platform on stenting as a treatment management for peripheral artery disease. The purpose of this health technology assessment is to examine the effectiveness of primary stenting as a treatment management for peripheral artery disease of the lower extremities. CONDITION AND TARGET POPULATION Peripheral artery disease (PAD) is a progressive disease occurring as a result of plaque accumulation (atherosclerosis) in the arterial system that carries blood to the extremities (arms and legs) as well as vital organs. The vessels that are most affected by PAD are the arteries of the lower extremities, the aorta, the visceral arterial branches, the carotid arteries and the arteries of the upper limbs. In the lower extremities, PAD affects three major arterial segments i) aortic-iliac, ii) femoro-popliteal (FP) and iii) infra-popliteal (primarily tibial) arteries. The disease is commonly classified clinically as asymptomatic claudication, rest pain and critical ischemia. Although the prevalence of PAD in Canada is not known, it is estimated that 800,000 Canadians have PAD. The 2007 Trans Atlantic Intersociety Consensus (TASC) II Working Group for the Management of Peripheral Disease estimated that the prevalence of PAD in Europe and North America to be 27 million, of whom 88,000 are hospitalizations involving lower extremities. A higher prevalence of PAD among elderly individuals has been reported to range from 12% to 29%. The National Health and Nutrition Examination Survey (NHANES) estimated that the prevalence of PAD is 14.5% among individuals 70 years of age and over. Modifiable and non-modifiable risk factors associated with PAD include advanced age, male gender, family history, smoking, diabetes, hypertension and hyperlipidemia. PAD is a strong predictor of myocardial infarction (MI), stroke and cardiovascular death. Annually, approximately

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

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

2016-02-01

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

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

Accessory renal arteries: Prevalence in resistant hypertension and an important role in nonresponse to radiofrequency renal denervation.

Science.gov (United States)

VonAchen, Paige; Hamann, Jason; Houghland, Thomas; Lesser, John R; Wang, Yale; Caye, David; Rosenthal, Kristi; Garberich, Ross F; Daniels, Mary; Schwartz, Robert S

The aim of this study was to understand the role of accessory renal arteries in resistant hypertension, and to establish their role in nonresponse to radiofrequency renal denervation (RDN) procedures. Prior studies suggest a role for accessory renal arteries in hypertensive syndromes, and recent clinical trials of renal denervation report that these anomalies are highly prevalent in resistant hypertension. This study evaluated the relationships among resistant hypertension, accessory renal arteries, and the response to radiofrequency (RF) renal denervation. Computed Tomography Angiography (CTA) and magnetic resonance imaging (MRI) scans from 58 patients with resistant hypertension undergoing RF renal denervation (RDN) were evaluated. Results were compared with CT scans in 57 healthy, normotensive subjects undergoing screening as possible renal transplant donors. All scans were carefully studied for accessory renal arteries, and were correlated with long term blood pressure reduction. Accessory renal arteries were markedly more prevalent in the hypertensive patients than normotensive renal donors (59% vs 32% respectively, p=0.004). RDN had an overall nonresponse rate of 29% (response rate 71%). Patients without accessory vessels had a borderline higher response rate to RDN than those with at least one accessory vessel (83% vs 62% respectively, p=0.076) and a higher RDN response than patients with untreated accessory arteries (83% vs 55%; p=0.040). For accessory renal arteries and nonresponse, the sensitivity was 76%, specificity 49%, with positive and negative predictive values 38% and 83% respectively. Accessory renal arteries were markedly over-represented in resistant hypertensives compared with healthy controls. While not all patients with accessory arteries were nonresponders, nonresponse was related to both the presence and non-treatment of accessory arteries. Addressing accessory renal arteries in future clinical trials may improve RDN therapeutic efficacy

Time-resolved MR angiography of the renal artery: morphology and perfusion

International Nuclear Information System (INIS)

Krause, U.J.; Pabst, T.; Koestler, H.; Helbig, C.; Kenn, W.; Hahn, D.

2002-01-01

Purpose: To prove the hypothesis that renal artery stenosis and changes in renal perfusion can be detected with contrast-enhanced time-resolved MR angiography in a single examination. Material and Methods: In 71 patients, 137 renal arteries and 14 accessory renal arteries were studied. The examinations were performed on a 1.5 T system. A T 1 -weighted gradient echo sequence with a temporal resolution of 7 s was used. Single dose of contrast material (0.1 mmol/kg Gd-DTPA) was injected with a power injector with a flow rate of 2 ml/s. Criterion for the assessment of renal perfusion was the slope ratio of the signal intensity time curve in both kidneys. Results: Forty renal artery stenoses and one occlusion of a renal artery were detected. In 48 kidneys (35%) segmental arteries were evaluated. The accuracy of the slope ratio (limit value 0.75) concerning the detection of unilateral renal artery stenosis was 92.6% (sensitivity 75%, specificity 95.7%). Conclusion: Time-resolved MR angiography can detect changes in renal perfusion in patients with unilateral renal artery stenosis. (orig.) [de

Enterprise stent in recanalizing non-acute atherosclerotic intracranial internal carotid artery occlusion.

Science.gov (United States)

Wang, Xiaofei; Wang, Zhigang; Ji, Yong; Ding, Xuan; Zang, Yizheng; Wang, Chengwei

2017-11-01

To investigate the safety and effectiveness of recanalization in non-acute occlusion of intracranial internal carotid arteries using the flexible Enterprise self-expanding stent. From June 2014 to June 2016, 12 consecutive patients with non-acute occlusion of intracranial internal carotid arteries received endovascular recanalization with Enterprise stenting. All patients received medication for anti-platelet aggregation therapy before and after the operation. The perioperative complications and recanalization efficacy were evaluated with the modified Rankin scoring system and digital subtraction angiography (DSA) follow-up, respectively. Endovascular recanalization was successfully performed in 10 out of 12 patients with Enterprise stenting. Stent implantation following balloon dilatation failed in one patient because the lumen diameter was too small. Another recanalization failed because the guide wire could not pass through the occlusion. No perioperative mortality was observed. One case of acute thrombosis and one case of intraoperative carotid spasm occurred, but these were resolved with thrombolytic therapy by microcatheter exposure treatment and antispasmodic medications, respectively. DSA follow-up in seven patients revealed no re-occlusion. One stroke event occurred in the 10 patients who completed the follow-up. A meaningful improvement in the modified Rankin score during follow-up was suggested by Wilcoxon signed-rank test results. The Enterprise stent was shown to be safe and efficient in recanalizing non-acute atherosclerotic intracranial internal carotid artery occlusion. However, the long-term outcomes need to be further investigated. Copyright © 2017 Elsevier B.V. All rights reserved.

Intra-renal localised reno-renal collaterals in the dog after tying of the main renal artery

International Nuclear Information System (INIS)

Rosenbusch, G.; Vincent, J.; Douveren, W. van; Sktonicki, S.; Arts, T.H.M.; Katholieke Univ. Nijmegen; Katholieke Univ. Nijmegen

1984-01-01

In 7 kidneys of 6 dogs one of the main stem of the renal artery was ligated. The development of the renorenal collaterals could be followed in 5, as two dogs died after the operation. In all cases intrarenal collaterals could be demonstrated, even in the postoperative dead dogs. The vessels responsible for the collateral circulation are preformed interarterial anastomoses, belonging to the extraglomerular arterial system. From the results of these and former experimental studies it can be concluded, that the renal artery of the dog when entering the renal sinus cannot be regarded as an anatomic, but at most as a functional end artery. (orig.) [de

Intra-renal localised reno-renal collaterals in the dog after tying of the main renal artery

Energy Technology Data Exchange (ETDEWEB)

Rosenbusch, G.; Vincent, J.; Douveren, W. van; Sktonicki, S.; Arts, T.H.M.

1984-01-01

In 7 kidneys of 6 dogs one of the main stem of the renal artery was ligated. The development of the renorenal collaterals could be followed in 5, as two dogs died after the operation. In all cases intrarenal collaterals could be demonstrated, even in the postoperative dead dogs. The vessels responsible for the collateral circulation are preformed interarterial anastomoses, belonging to the extraglomerular arterial system. From the results of these and former experimental studies it can be concluded, that the renal artery of the dog when entering the renal sinus cannot be regarded as an anatomic, but at most as a functional end artery.

Diagnosis of renal artery stenosis : spiral CTA vs. IA-DSA

International Nuclear Information System (INIS)

Kim, Tae Sung; Chung, Jin Wook; Park, Jae Hyung; Kim, Seung Hyup; Yeon, Kyung Mo; Han, Man Chung

1996-01-01

To evaluate the accuracy of spiral CT angiography(CTA) in the demonstration of accessory or multiple renal arteries and renal artery stenosis. We prospectively performed CTA in 50 patients (24 males and 26 females) between nine and 77 years old (mean 39.3) in whom renovascular hypertension was suspected (n=32), or who were potential renal donors (n=18). Within two days of CTA, intraarterial digital subtraction angiography(IA-DSA) was performed. Both spiral CTA and IA-DSA images were blindly compared by two radiologists with respect to the number of accessory renal arteries and the location and severity of renal artery stenosis. The severity of renal arterial stenosis was graded with a five-point scale (grades 0-4). CTA demonstrated 26 of total 27 accessory renal arteries (detection rate=96.5%). For the diagnosis of grade 2-4 stenosis (≥50% stenosis) (n=40 of a total of 127 renal arteries), the sensitivity, specificity, and accuracy of CTA were 90%, 96.5%, and 94.5%, respectively. For the detection of grade 3-4 stenoses (≥75% stenosis) (n=33), the sensitivity, specificity, and accuracy of CTA were 87.9%, 98.9%, and 96.1%, respectively. For the detection of grade 3-4 stenoses in the main renal artery (n=27), the sensitivity, specificity, and accuracy of CTA were 96.3%, 100%, and 99.0%, respectively. Spiral CTA is a reliable and accurate screening modality for the evaluation of renal artery in patients suspected to be suffering from renovascular hypertension, or who are potential renal donors

Renal artery stenosis after radiotherapy for Ewing's sarcoma

International Nuclear Information System (INIS)

Tacconi, S.; Bieri, S.

2008-01-01

Background: the fact that therapeutic irradiation can induce significant stenosis in the arteries of the head, neck, and chest, as welt as in the aorta and the iliac arteries, is familiar in daily practice and well documented in the literature. By contrast, radiation-induced renal artery stenosis seems to be a less widely known complication. Patients and methods: the sudden onset of medically refractory arterial hypertension and coma in a 27-year-old man is reported, who had been treated at age 20 with chemotherapy and radiotherapy for Ewing's sarcoma in the lumbar region. This treatment had been performed at the hospital of Sion, Switzerland in 2001. Also, the relevant literature from 1965 to 2007 is reviewed to underscore various aspects of this problem and to demonstrate the clinical relevance of renal artery stenosis as a potential long-term sequela of radiotherapy. Conclusion: radiation-induced renal artery stenosis has only rarely been described in the literature, but arterial hypertension due to radiation-induced renal artery stenosis is a serious long-term sequela that can appear at a latency of up to 20 years after treatment. The paucity of reports presumably reflects the lesser frequency of radiotherapy for retroperitoneal tumors as compared to head-and-neck cancers, as well as lower awareness of the problem due to diagnostic bias in the era before CT and MRI were in routine use: at that time, carotid artery stenosis was easy to diagnose by ultrasonography, while radiation-induced renal artery stenosis, whose real incidence may well be higher, probably often went undetected. Thus, when a patient with a history of abdominal or retroperitoneal radiotherapy unexpectedly develops intractable hypertension, radiation-induced renal artery stenosis must be included in the differential diagnosis. (orig.)

Use of a Stent Graft for Bleeding Hepatic Artery Pseudoaneurysm Following Pancreaticoduodenectomy

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Leoncio L. Kaw, Jr

2006-10-01

Full Text Available Although uncommon, bleeding following pancreaticoduodenectomy is associated with high mortality. Management generally includes surgical reexploration or, alternatively, transarterial embolization. We report the case of a 62-year-old man who presented with massive upper gastrointestinal bleeding 3 weeks after pancreaticoduodenectomy. Selective coeliac angiography revealed a large pseudoaneurysm involving the proper hepatic artery. This was treated successfully with a stent graft. There was no recurrence of bleeding at the 6-month follow-up. To our knowledge, this is the first report of stent graft repair of bleeding hepatic artery pseudoaneurysm following pancreaticoduodenectomy.

Efficacy of Carotid Artery Stenting by the Universal Protection Method.

Science.gov (United States)

Goto, Shunsaku; Ohshima, Tomotaka; Kato, Kyozo; Izumi, Takashi; Wakabayashi, Toshihiko

2018-04-18

To avoid distal plaques embolization during carotid artery stenting, we developed Universal Protection Method that combined the use of a proximal common carotid artery balloon, an external carotid artery balloon, and a distal internal carotid artery filter, with continuous flow reversal to the femoral vein. Herein, we assessed the efficacy of the Universal Protection Method by comparing stenting outcomes before and after its introduction. We assessed outcomes for 115 cases before and 41 cases after the Universal Protection Method was adopted (non-Universal Protection Method and Universal Protection Method groups, respectively). We then compared procedure details, magnetic resonance imaging (within 48 hours after the procedure), intraprocedural complications, and postoperative stroke rates. Ischemic stroke was not observed in the Universal Protection Method group, but 1 major stroke and 2 minor strokes were observed in the non-Universal Protection Method group. High-intensity areas were seen in 6 (15.0%) and 49 (42.6%) cases in the Universal Protection Method and non-Universal Protection Method groups, respectively (P = .001). Contrastingly, intraprocedural complications were observed in 9 (22.5%) and 21 (18.3%) cases in the Universal Protection Method and non-Universal Protection Method groups, respectively. Among these intraprocedural complication cases, high-intensity areas were observed in 1 case (11.1%) in the Universal Protection Method group and in 15 cases (71.4%) in the non-Universal Protection Method group. Universal Protection Method is a safe technique that is applicable to all patients undergoing carotid artery stenting, irrespective of individual risk factors. Notably, the incidence rates of both distal embolization and unexpected intraprocedural complications are low. Copyright © 2018 National Stroke Association. Published by Elsevier Inc. All rights reserved.

Variant anatomy of renal arteries in a Kenyan population.

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Ogeng'o, Julius A; Masaki, Charles O; Sinkeet, Simeon R; Muthoka, Johnstone M; Murunga, Acleus K

2010-01-01

Variant anatomy of renal arteries is important in renal transplant, vascular reconstruction, and uroradiological procedures. The variations show ethnic and population differences. Data from Africans are scarce and altogether absent for Kenyans. To describe patterns of origin, trajectories and branching of renal arteries in a Kenyan population. Descriptive cross-sectional study conducted in the Department of Human Anatomy, University of Nairobi. Three hundred and fifty six kidneys from 178 cadavers and postmortem specimens were used in the study. Aorta, renal arteries and kidneys were exposed by dissection. Number, trajectories, level of branching, number of branches and point of entry into the kidney were recorded. Data was analyzed using SPSS version 16.0, and presented using macrographs, tables, and bar charts. Additional arteries occurred in 14.3% of the cases. In 82.4% of these, there was one additional artery. Fifty nine point five per cent of the double renal arteries were parallel and 7.1% crossed. Of the 305 single arteries, 76.4% showed hilar, 21.6% prehilar and 2% intraparenchymal branching. In the hilar branching, ladder type was present in 65% and fork type in 35%. Bifurcation and trifurcation were present in 59.6% and 33.1% respectively. Polar arteries were present in 16.9% cases. Over 14% of the Kenyan population may have additional renal arteries while more than 20% show early branching. Several trajectories and hilar branching patterns exist which renal transplant surgeons and radiologists should be aware of to avoid inadvertent vascular injury.

Impaired renal allograft function is associated with increased arterial stiffness in renal transplant recipients

DEFF Research Database (Denmark)

Kneifel, M; Scholze, A; Burkert, A

2006-01-01

It is important whether impairment of renal allograft function may deteriorate arterial stiffness in renal transplant recipients. In a cross-sectional study, arterial vascular characteristics were non-invasively determined in 48 patients with renal allograft using applanation tonometry and digital...

Value of downstream circulation in renal artery stenosis with arterial hypertension: comparison between color Doppler flow and digital renal angiography in 123 patients

International Nuclear Information System (INIS)

Grataloup, C.; Challande, P.; Plainfosse, M.C.; Girerd, X.; Belattar, K.; Plouin, P.F.

1996-01-01

Digital renal angiography and color Doppler flow were compared for diagnosis of renal artery stenosis in 123 hypertensive patients with a prevalence of renal artery stenosis ≥75% of 21 %. Only color Doppler flow signs found downstream from the stenosis could be quantified. A rising time (RT) >0.07 s was the best marker for renal artery stenosis ≥ 75 % according to a receiver operating characteristic curve with a specificity of 97 %, a sensitivity of 88 %, a positive predictive value of 86 %, a negative predictive value of 98 % and an accuracy of 96 %. Digital renal angiography and color Doppler flow findings for renal artery lesions were classified into 4 degrees with agreement for 86 % of the kidneys. (authors). 13 refs., 5 figs., 8 tabs

Evaluation of peripheral artery stent with 64-slice multi-detector row CT angiography: Prospective comparison with digital subtraction angiography

International Nuclear Information System (INIS)

Li Xiaoming; Li Yuhua; Tian Jianming; Xiao Yi; Lu Jianping; Jing Zaiping; Sheng Jing; Edwin, Angela; Wu Fanghong

2010-01-01

Purpose: To assess the accuracy of 64-slice multi-detector row computed tomography (MDCT) angiography in the evaluation of peripheral artery in-stent or peristent restenosis, with conventional digital subtraction angiography (DSA) as the reference standard. Materials and methods: Forty-one patients (30 men, 11 women; mean age, 69.8 ± 9.2 years) with symptomatic peripheral arterial occlusive disease after peripheral artery stenting (81 stented lesions) underwent both conventional DSA and 64-slice MDCT angiography. Each stent was classified as evaluable or unevaluable, and every stent was divided into three segments (proximal stent, stent body, and distal stent), resulting in 243 segments. For evaluation, stenosis was graded as follows: 1, none or slight stenosis (<25%); 2, mild stenosis (25-49%); 3, moderate stenosis (50-74%); 4, severe stenosis or total occlusion (≥75%). Two readers evaluated all CT angiograms with regard to narrowing of in-stent or peristent restenosis by consensus. Results were compared with findings of the DSA. Results: Of 81 stents, 62 (76.5%) were determined to be assessable. The metal artifact of the gold marker and motion artifact increased uninterpretability of the images of stents. Overall, 24 of 28 in-stent restenosis and 38 of 53 persistent restenosis were correctly detected by MDCT (85.7% and 71.7% sensitivity). In evaluable stents, 21 of 22 in-stent restenoses and 27 of 28 persistent restenosis were correctly detected (95.4% and 96.4% sensitivity). Additionally, as the grade of stenosis increases, the mean level of CT values in the stent lumina decreases linearly accordingly. Conclusion: 64-Slice MDCT has a high accuracy for the detection of significant in-stent or peristent restenosis of assessable stents in patients with peripheral artery stent implantation and therefore can be considered as a valuable noninvasive technique for stent surveillance.

Impact of Chronic Renal Failure on Safety and Effectiveness of Paclitaxel-Eluting Stents for Femoropopliteal Artery Disease: Subgroup Analysis from Zilver PTX Post-Market Surveillance Study in Japan.

Science.gov (United States)

Ogawa, Yukihisa; Yokoi, Hiroyoshi; Ohki, Takao; Kichikawa, Kimihiko; Nakamura, Masato; Komori, Kimihiro; Nanto, Shinsuke; O'Leary, Erin E; Lottes, Aaron E; Saunders, Alan T; Dake, Michael D

2017-11-01

Favorable long-term outcomes of the Zilver PTX drug-eluting stent (DES) in femoropopliteal lesions have been demonstrated. Chronic renal failure (CRF) has been shown to be a risk factor for restenosis and decreased limb salvage. The results of the DES in patients with CRF have not previously been reported. This study compares the results with the DES in patients with CRF and those without CRF. This retrospective analysis from the Zilver PTX Japan Post-Market Surveillance Study included 321 patients with CRF and 584 patients without CRF. Outcomes included freedom from target lesion revascularization (TLR) and patency. Of the patients included in this subgroup analysis, 2-year data were available for 209 patients in the CRF group and 453 patients in the non-CRF group. The two groups were similar in terms of lesion length and the frequency of in-stent restenosis. Critical limb ischemia, severe calcification, and diabetes were more common in patients with CRF, whereas total occlusion was more common in patients without CRF. Freedom from TLR rates were 81.4 versus 84.9% (p = 0.24), and patency rates were 70.7 versus 70.3% (p = 0.95) in patients with and without CRF at 2 years, respectively. This is the first comparative study of the DES in femoropopliteal artery lesions in patients with and without CRF. These results indicate that the DES placed in femoropopliteal artery lesions of CRF patients is safe and effective with similar patency and TLR rates to patients without CRF. Level 3, Post-Market Surveillance Study.

Renal hemodynamics: the influence of the renal artery ostium flow diverter

Science.gov (United States)

Rossmann, Jenn Stroud; Albert, Scott; Balaban, Robert

2013-11-01

The recently identified renal artery ostium flow diverter may preferentially direct blood flow to the renal arteries, and may also influence flow patterns and recirculation known to be involved in atherogenesis. Three-dimensional computational fluid dynamics (CFD) simulations of steady and pulsatile blood flow are performed to investigate the influence of diverter size and position, and vascular geometry, on the flow patterns and fluid mechanical forces in the neighborhood of the diverter. CFD results show that the flow diverter does affect the blood distribution: depending on the diverter's position, the flow to the renal arteries may be increased or reduced. The results of simulations also show the diverter's effect on the Wall Shear Stress (WSS) distribution, and suggest that the diverter contributes to an atherogenic environment in the abdominal aorta, while being atheroprotective in the renal arteries themselves. These results support previous clinical findings, and suggest directions for further clinical study. The results of this work have direct implications in understanding the physiological significance of the diverter, and its potential role in the pathophysiological development of atherosclerosis.

Dual-artery stenting of a type III single coronary artery from right aortic sinus

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Shivanad Patil

2015-12-01

Full Text Available A single coronary artery presenting with stenosis in two of the three vessels arising from a common ostium is a rare anomaly Lipton et al. proposed a classification, which was modified by Yamanaka and Hobbs. In our case, a single coronary artery was giving rise to the LAD, left circumflex (LCx, and the right coronary artery (RCA. There was 80% stenosis in the ostium of the LCx. The RCA in the mid and distal segment had stenosis of 80% and 70%, respectively. We were able to successfully stent the three stenotic segments.

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)

Acute Carotid Artery Stent Thrombosis Due to Dual Antiplatelet Resistance

International Nuclear Information System (INIS)

Köklü, Erkan; Arslan, Şakir; Yüksel, İsa Öner; Bayar, Nermin; Koç, Pınar

2015-01-01

Carotid artery stenting (CAS) is a revascularization modality that is an alternative to carotid endarterectomy. The efficacy of CAS in primary and secondary prevention from ischemic stroke has been demonstrated in various trials. Acute thrombosis of CAS is a rare complication that can lead to dramatic and catastrophic consequences. We discuss a case of acute CAS thrombosis in a patient who had previously undergone successful CAS. CAS was performed in a 73-year-old man who had had dysarthria lasting 2 weeks with 95 % stenosis in his left internal carotid artery. An acute cerebrovascular event resulting in right-sided hemiplegia developed 24 h after the procedure. Computed tomographic carotid angiography revealed complete occlusion of the stent with thrombus. The cause of stent thrombosis was thought to be antiaggregant resistance to both acetylsalicylic acid and clopidogrel. The most important cause of acute CAS thrombosis is inadequate or ineffective antiaggregant therapy. Evaluating patients who are candidates for CAS for acetylsalicylic acid and clopidogrel resistance may preclude this complication

Fibrosing Mediastinitis: Successful Stenting of the Pulmonary Artery

Directory of Open Access Journals (Sweden)

Rennae Thiessen

2008-01-01

Full Text Available Fibrosing mediastinitis is a rare benign condition, which can cause compression of the pulmonary or systemic vessels, tracheobronchial tree, coronary arteries or esophagus, leading to disabling clinical symptoms and even death. The case of a 26-year-old woman who presented with dyspnea is described. She was found to have 80% stenosis of the right pulmonary artery secondary to fibrosing mediastinitis. The stenosis was managed successfully with an endovascular Palmaz-Schatz stent, and the patient remains symptom-free 10 years later.

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

International Nuclear Information System (INIS)

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

2010-01-01

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

Superselective renal artery embolization with lipiodol and absolute alcohol emulsion for renal tumor

International Nuclear Information System (INIS)

Yu Miao; Li Jiakai; Sun Minglu; Wang Huixian

2008-01-01

Objective: To evaluate the efficacy of the renal arterial embolization with lipidol and absolute alcohol emulsion in the treatment of renal tumors. Methods: The superselective renal arterial embolization by using coaxial-cathaterization with infusion of lipiodol and absolute alcohol (in proportion of 2 :1) emulsion was performed in twenty patients with malignant and benign kidney tumors. 4 weeks later, the renal arteriography was taken routinely and repeated embolization was performed in case of necessary; and follow up was carried out periodically. Results: The imaging findings showed thorough tumor necrosis and feeding vessel abruption in 18 cases after one session of treatment. The volume of tumors decreased more than a half in 13 patients (82.25%, 13/18) associated with a well-distributed lipidol inside the tumors. The second session of treatment was performed in other 2 patients and the clinical symptoms relieved obviously. Conclusions: The superselective renal artery embolization with lipidol and absolute alcohol emulsion can permanently embolize all tumor feeding arteries in capillary vessel level with maximum reservation of renal function, providing definitively efficacy and worthwhile to be recommended widely. (authors)

Arrangement of Renal Arteries in Guinea Pig.

Science.gov (United States)

Mazensky, David; Flesarova, Slavka

2017-03-01

The aim of this study was to describe origin, localization, and variations of renal arteries in guinea pig. The study was carried out on 26 adult guinea pigs. We prepared corrosion casts of the guinea pig arterial system. Batson's corrosion casting kit no. 17 was used as the casting medium. In 57.7% of specimens, a. renalis dextra was present as a single vessel with different level of its origin from aorta abdominalis. In 38.5% of specimens, two aa. renales dextrae were present with variable origin and arrangement. The presence of three aa. renales dextrae we found in one specimen. In 76.9% of specimens, a. renalis sinistra was present as a single vessel with different level of its origin from aorta abdominalis and variable arrangement. In 23.1% of specimens, we found two aa. renales sinistrae with variable origin and arrangement. The anatomical knowledge of the renal arteries, and its variations are of extreme importance for the surgeon that approaches the retroperitoneal region in several experiments, results of which are extrapolated in human. This is the first work dealing with the description of renal arteries arrangement in guinea pig. Anat Rec, 300:556-559, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Stent-Graft Repair of a Large Cervical Internal Carotid Artery Pseudoaneurysm Causing Dysphagia

International Nuclear Information System (INIS)

Gupta, Vivek; Niranjan, Khandelwal; Rawat, Lokesh; Gupta, A. K.

2009-01-01

Pseudoaneurysms of the cervical internal carotid artery (ICA) are rare and most frequently result from trauma, infection, or sometimes spontaneously. They have the potential to cause life-threatening hemorrhage; thus, their immediate management is necessary. Endovascular treatment by stent graft placement in the affected artery appears to be a safe and effective treatment option. We present a case of a child who presented with neck swelling and dysphagia caused by a ruptured cervical ICA pseudoaneurysm which was managed by stent graft placement.

Does complete renal denervation translate into superior clinical outcomes? Lessons learned from denervation of accessory renal arteries

OpenAIRE

Mendelsohn, Farrell O.

2014-01-01

Pre-clinical studies of renal denervation would suggest that the extent of renal nerve injury correlates with outcomes. The “completeness” of renal nerve injury following renal denervation correlates with treatment-based variables such as the depth of ablation, the number of ablations along the length of the artery, and the number of renal arteries successfully ablated. Renal denervation techniques targeting only main renal arteries may lead to suboptimal results in patients with accessory re...

Fracture and Collapse of Balloon-Expandable Stents in the Bilateral Common Iliac Arteries Due to Shiatsu Massage

Energy Technology Data Exchange (ETDEWEB)

Ichihashi, Shigeo, E-mail: shigeoichihashi@yahoo.co.jp; Higashiura, Wataru; Itoh, Hirofumi; Sakaguchi, Shoji; Kichikawa, Kimihiko [Nara Medical University, Department of Radiology (Japan)

2012-12-15

We report a case of stent fracture and collapse of balloon-expandable stents caused by shiatsu massage. A 76-year-old man presented with complaints of intermittent claudication of the right lower extremity. Stenoses of the bilateral common iliac arteries (CIAs) were detected. Balloon-expandable stents were deployed in both CIAs, resulting in resolution of symptoms. Five months later, pelvis x-ray showed collapse of both stents. Despite the stent collapse, the patient was asymptomatic, and his ankle brachial index values were within the normal range. Further history showed that the patient underwent daily shiatsu therapy in the umbilical region, which may have triggered collapse of the stent. Physicians should advise patients to avoid compression of the abdominal wall after implantation of a stent in the iliac artery.

Fracture and Collapse of Balloon-Expandable Stents in the Bilateral Common Iliac Arteries Due to Shiatsu Massage

International Nuclear Information System (INIS)

Ichihashi, Shigeo; Higashiura, Wataru; Itoh, Hirofumi; Sakaguchi, Shoji; Kichikawa, Kimihiko

2012-01-01

We report a case of stent fracture and collapse of balloon-expandable stents caused by shiatsu massage. A 76-year-old man presented with complaints of intermittent claudication of the right lower extremity. Stenoses of the bilateral common iliac arteries (CIAs) were detected. Balloon-expandable stents were deployed in both CIAs, resulting in resolution of symptoms. Five months later, pelvis x-ray showed collapse of both stents. Despite the stent collapse, the patient was asymptomatic, and his ankle brachial index values were within the normal range. Further history showed that the patient underwent daily shiatsu therapy in the umbilical region, which may have triggered collapse of the stent. Physicians should advise patients to avoid compression of the abdominal wall after implantation of a stent in the iliac artery.

Anatomical variations of hepatic arterial system, coeliac trunk and renal arteries: an analysis with multidetector CT angiography.

Science.gov (United States)

Ugurel, M S; Battal, B; Bozlar, U; Nural, M S; Tasar, M; Ors, F; Saglam, M; Karademir, I

2010-08-01

The purpose of our investigation was to determine the anatomical variations in the coeliac trunk-hepatic arterial system and the renal arteries in patients who underwent multidetector CT (MDCT) angiography of the abdominal aorta for various reasons. A total of 100 patients were analysed retrospectively. The coeliac trunk, hepatic arterial system and renal arteries were analysed individually and anatomical variations were recorded. Statistical analysis of the relationship between hepatocoeliac variations and renal artery variations was performed using a chi(2) test. There was a coeliac trunk trifurcation in 89% and bifurcation in 8% of the cases. Coeliac trunk was absent in 1%, a hepatosplenomesenteric trunk was seen in 1% and a splenomesenteric trunk was present in 1%. Hepatic artery variation was present in 48% of patients. Coeliac trunk and/or hepatic arterial variation was present in 23 (39.7%) of the 58 patients with normal renal arteries, and in 27 (64.3%) of the 42 patients with accessory renal arteries. There was a statistically significant correlation between renal artery variations and coeliac trunk-hepatic arterial system variations (p = 0.015). MDCT angiography permits a correct and detailed evaluation of hepatic and renal vascular anatomy. The prevalence of variations in the coeliac trunk and/or hepatic arteries is increased in people with accessory renal arteries. For that reason, when undertaking angiographic examinations directed towards any single organ, the possibility of variations in the vascular structure of other organs should be kept in mind.

Massive Bleeding from Guidewire Perforation of an External Iliac Artery: Treatment with Hand-made Stent-Graft Placement

Energy Technology Data Exchange (ETDEWEB)

Mehta, Vimal, E-mail: drvimalmehta@yahoo.co.in; Pandit, Bhagya Narayan; Mehra, Pratishtha; Nigam, Arima; Vyas, Aniruddha; Yusuf, Jamal; Mukhopadhyay, Saibal; Trehan, Vijay [G.B. Pant Institute of Postgraduate Medical Education and Research (India)

2016-01-15

We report life-threatening bleeding from an external iliac artery perforation following guidewire manipulation in a patient with atherosclerotic iliac artery disease. This complication was successfully managed by indigenous hand-made stent-graft made from two peripheral stents in the catheterization laboratory.

Massive Bleeding from Guidewire Perforation of an External Iliac Artery: Treatment with Hand-made Stent-Graft Placement

International Nuclear Information System (INIS)

Mehta, Vimal; Pandit, Bhagya Narayan; Mehra, Pratishtha; Nigam, Arima; Vyas, Aniruddha; Yusuf, Jamal; Mukhopadhyay, Saibal; Trehan, Vijay

2016-01-01

We report life-threatening bleeding from an external iliac artery perforation following guidewire manipulation in a patient with atherosclerotic iliac artery disease. This complication was successfully managed by indigenous hand-made stent-graft made from two peripheral stents in the catheterization laboratory

Power doppler ultrasound findings of renal infarct after experimental renal artery occlusion: comparison with spiral CT

International Nuclear Information System (INIS)

Jung, Seung Eun; Shinn, Kyung Sub; Kim, Hak Hee; Mun, Seok Hwan; Lee, Young Joon; Lee, Bae Young; Choi, Byung Gil; Lee, Jae Mun; Lee, Hee Jeong

1999-01-01

To evaluate the efficacy of power Doppler ultrasonography (PDUS) in depicting renal infarction in rabbits during experimental renal segmental arterial occlusion, and to compare the results with those of CT scanning. In 28 rabbits weighing 2.5 4kg, the segmental renal artery was occluded through the left main renal artery by embolization with Ivalon (Nycomed, Paris, France). Power Doppler ultrasonography and spiral CT scanning were performed before and at 2, 5, 8, 15, and 24 hours, and 3 and 7 days after occlusion of the segmental renal artery. The location of infarcted areas and collaterals, as seen on PDUS and CT scans, was evaluated by two radiologists. In all cases, as seen on power Doppler ultrasonography, infarcted areas-when compared with normal parenchyma, clearly demonstrated wedge-shaped perfusion defects in the kidney. The location of the lesion closely corresponded to the location seen during CT scanning. After renal arterial occlusion, transiently congested capsular arteries, which were named 'capsular sign', were seen in 63% of rabbits in the two and five-hour groups. No significant cortical rim sign was demonstrated on power Doppler ultrasonography, though it was noted on spiral CT at 15 and 24 hours, and 3 and 7 days after renal arterial occlusion. Power Doppler ultrasonography was useful for the diagnosis of renal infarction. Congested capsular artery seen in the early stage of renal infarction might be a characteristic finding of this condition, as seen on power Doppler ultrasonography

Detection of renal arteries with fast spin-echo magnetic resonance imaging

Energy Technology Data Exchange (ETDEWEB)

Tello, R.; Mitchell, P.J.; Witte, D.J.; Thomson, K.R. [University of Melbourne, Parkville, VIC (Australia). Department of Radiology

1998-08-01

With the increasing use of non-invasive imaging with MR and volumetric CT to evaluate renal arteries, the ability to accurately detect the number and state of native renal arteries becomes critical if conventional angiography is to be supplanted in these settings. The present study evaluated the utility of a fast spin-echo (FSE) T2-weighted sequence to detect the number and course of renal arteries and their ostia compared to conventional angiography. Ten patients underwent conventional catheter angiography either for renal artery stenosis evaluation or as potential renal donors. Each patient then had an MR study of the renal arteries and kidneys with FSE MR (TR = 4000 ms, TE = 102 ms, eight- echo train length, 5-mm-thick interleaved 128 phase encodes, superior and inferior saturation pulses, number of excitations (NEX) = 4, on a 1.5-T superconducting magnet). Images were reviewed by two `blinded` radiologists and renal arteries were counted and their ostia were evaluated. Results were compared with angiography and inter- and intra-observer statistics were calculated. All 10 patients underwent MR successfully, nine for renal artery stenosis (RAS) evaluation and one was a renal donor. A total of 24 renal arteries were imaged in 19 kidneys. Fast spin-echo MR is 95% accurate (95%CI: 88-100%) in detection of renal arteries, with no statistical difference between FSE MR and catheter angiography (McNemar P = 0.0). Inter- and intra-observer statistics demonstrate good-to-excellent agreement in renal artery detection (kappa: 0.63-0.90). In one case of RAS evaluation an incidental adrenal mass was detected as the aetiology of the patient`s hypertension. Fast spin-echo MR can be a useful adjunct as part of the imaging for renal arteries with MRI. Copyright (1998) Blackwell Science Pty Ltd 16 refs., 1 fig.

Detection of renal arteries with fast spin-echo magnetic resonance imaging