Self-expanding Nitinol Stent Implantation Research Articles

Long-term Outcomes After Self-Expanding Nitinol Stent Implantation for the Treatment of Lesions in the Superficial Femoral Artery And Proximal Popliteal Artery: 3-Year Results From the BIOFLEX-I Trial

Long-term Outcomes After Self-Expanding Nitinol Stent Implantation for the Treatment of Lesions in the Superficial Femoral Artery And Proximal Popliteal Artery: 3-Year Results From the BIOFLEX-I Trial

Long term clinical outcome after self-expandable nitinol stent implantation for femoropopliteal occlusive disease in hemodialysis patients

Abstract Background Endovascular therapy (EVT) using self-expandable bare nitinol stent (BNS) has been commonly accepted in patients with symptomatic femoropopliteal (FP) occlusive disease. However, poor clinical outcomes in hemodialysis (HD) patients are major problems. We investigated the impact of HD on clinical outcome after EVT in patients with FP disease. Methods A total of 427 consecutive HD patients undergoing successful EVT with BNS for FP disease were enrolled with 157 non-HD patients as a control group. They were followed-up for 5 years. We collected data on target lesion revascularization (TLR) rate, and limb salvage rate as well as survival rate. Propensity-score matching analysis was performed to investigate the true impact of HD on the outcome. Results Critical limb ischemia was observed in 44.0% of overall population (43.0% in HD group vs. 46.8% in non-HD group, p=0.42). Rates of diabetes (67.1% vs. 58.1%, p=0.045) and coronary artery disease (73.5% vs. 58.3%, p=0.0008) were higher, while age (70±10 years old vs. 76±10 years old, p<0.0001) and TASC2 C/D lesion (27.9% vs. 44.6%, p=0.0002) were lower in HD group compared to non-HD group. Pre-procedural C-reactive protein level (0.4mg/l vs. 0.3mg/l, p=0.045) was higher and serum albumin level (3.6g/dl vs. 3.8g/dl, p=0.0045) was lower in HD group than those in non-HD group. The freedom rate from TLR at 5 years was significantly lower in HD group than in non-HD group [47.2% vs. 65.2%, hazard ratio (HR) 1.77, 95% confidence interval (CI) 1.23–2.64, p=0.0017]. The limb salvage rate was comparable between the groups (93.3% vs. 97.1%, HR 1.57, 95% CI 0.58–5.47, p=0.41), while the survival rate was significantly lower in HD group compared to non-HD group (60.6% vs. 86.0%, HR 2.53, 95% CI 1.56–4.36, p=0.0002). After propensity-score analysis, 250 patients (125 in each group) were matched without any difference of clinical characteristics in both groups. In the matched cohort, the freedom rate from TLR was still lower in HD group compared to non-HD group (46.7% vs. 66.6%, HR 2.25, 95% CI 1.35–3.87, p=0.0019). The adjusted limb salvage rate was consistently similar between the groups (95.4% vs. 97.3%, HR 1.10, 95% CI 0.20–5.94, p=0.91). Also, the adjusted survival rate was lower in HD group than in non-HD group (47.6% vs. 89.9%, HR 3.60, 95% CI 1.89–7.44, p<0.0001). Conclusion The freedom rate from TLR at 5 years after BNS implantation for FP disease were significantly lower in HD group than in non-HD group, though the limb salvage rate was similar between the groups. The survival rate was consistently lower in HD group compared to non-HD group. HD status had a great impact on TLR and mortality after EVT with BNS in patients with FP disease. Funding Acknowledgement Type of funding source: None

Kalsifiye Stenotik Süperfisyal Femoral Arter Lezyonlarının Tedavisinde Direksiyonel Aterektomi ile Kombine Edilmiş Paklitaksel Salınımlı Balon Anjioplasti ve Kendiliğinden Açılan Nitinol Stent Uygulamasının Karşılaştırılması

Aim: The frequency and variety of endovascular interventions have increased with the rise in peripheral arterial occlusive disease incidence and to lessen undesirable outcomes after peripheral vascular surgery. Extensive calcific stenotic lesions affect patency rates of endovascular interventions and enhance complication rates. In this study we aimed to compare paclitaxel eluting balloon angioplasty (PEBA) combined with directional atherectomy (DA) with self expandable nitinol stent (SENS) implantation in terms of patency rates.Material and Methods: Fifty-six patients (28 patients in each group) underwent endovascular interventions for calcific stenotic superficial femoral artery lesions between March 2013 and May 2014 at Cardiovascular Surgery clinic in Namık Kemal University Hospital were included in the study. Mean age was 65.4±7.6 and male to female ratio was 46/10. Patients were followed up with ankle brachial index (ABI), Rutherford score (RS) and Doppler ultrasonography (DUSG) from the pre-intervention period to sixth month after intervention.Results: Mean lesion length in DA and PEBA group was 66.4±24.8 mm and 65.0±20.6 mm in SENS group. Primary and secondary patency rates were 85.7% and 92.9% in DA and PEBA group, and 57.1% and 71.4% in SENS group in six months follow up. There was a statistically significant difference between groups. Significant improvement was detected in terms of ABI and RS in both groups.Conclusion: We conclude from this study results that PEBA combined with DA is better than SENS implantation, because of its successful early-term results, no intravascular foreign bodies, and continues the chance of surgery without affecting the anastomosis field.

P3569Predictive value of vessel size for the long-term patency following self-expanding nitinol stent implantation in the superficial femoral artery

P3569Predictive value of vessel size for the long-term patency following self-expanding nitinol stent implantation in the superficial femoral artery

TCTAP A-132 Impact of Stent Diameter on Stent Patency After Self-expanding Nitinol Stent Implantation in the Superficial Femoral Artery

TCTAP A-132 Impact of Stent Diameter on Stent Patency After Self-expanding Nitinol Stent Implantation in the Superficial Femoral Artery

Long-term risks for patency loss in patients with hemodialysis after bare self-expandable nitinol stent implantation to femoropopliteal artery occlusive lesions

BackgroundAlthough patients receiving hemodialysis (HD+) have significantly different backgrounds, including a history of progressive atherosclerotic disease, compared with those not receiving hemodialysis (HD−), there are no studies evaluating the risks for loss of primary patency (PP) and need for target lesion revascularization (TLR) in HD+ patients following bare self-expandable nitinol stent (BSNS) implantation to femoropopliteal (FP) artery occlusive lesions, after adjusting for differences using propensity score (PS) analysis in observed characteristics between groups. MethodsWe studied 531 limbs of 432 Japanese patients (HD+, n=107; HD−, n=325) who received BSNS implantation to FP lesions between 2004 and 2014. Patients were followed-up for an average of 44.3±33.6months. We compared the long-term results between HD+ and HD− patients using the Cox-proportional hazard model with adjustment for inverse probability treatment weight (IPTW) of PS, which was calculated for covariates with HD as a dependent variable. ResultsPP rate in HD+ vs. HD− patients at 9years after the procedure was 19.1% vs. 47.9%, with a freedom from TLR rate of 47.6% vs. 62.9%, respectively. Adjusted HRs in HD+ patients with 95% confidence intervals (CIs) were as follows: loss of PP: HR 1.64, 95% CI 1.052–2.557, P=0.03; TLR: HR 1.862, 95% CI 1.104–3.139, P=0.02. ConclusionsThe present study suggests that HD+ patients have an increased risk for loss of PP and need for TLR after BSNS implantation to FP lesions.

IMPACT OF NITINOL SELF-EXPANDING STENT ON THE PATENCY OF SUBINTIMAL ANGIOPLASTY FOR BELOW-THE-KNEE OCCLUSIONS WITH CRITICAL LIMB ISCHEMIA (NEXSIA-BTK): MULTICENTER, PROSPECTIVE REGISTRY

Subintimal angioplasty (SIA) is an efficient interventional approach for recanalization of long below-the-knee (BTK) chronic total occlusions (CTOs) in patients with critical limb ischemia (CLI). However, whether primary implantation of self-expanding nitinol stent in BTK lesions after SIA can

Chronic vascular response after self-expanding nitinol stent implantation in superficial femoral arteries: a serial intravascular ultrasound analysis

The mechanical properties of the self-expanding nitinol stents (SENS) and chronic biological stimulation on the wall from the SENS have not been fully investigated. This study evaluated the mechanical vascular response to SENS implantation in superficial femoral artery (SFA) lesions using serial volumetric intravascular ultrasound (IVUS). Twenty-five symptomatic patients due to de novo SFA lesions scheduled for SENS placement were prospectively enrolled. Serial IVUS studies were performed immediately after crossing with a guidewire, immediately after the procedure, and at a 8-month follow-up. Serial IVUS volumetric analysis was conducted after stent deployment and at follow-up. Mean stent, lumen and neointimal areas were calculated as the volume divided by the stent length, and the calcium arc was measured. At follow-up, SENS had increased 40.6% in overall volume. The chronic stent expansion tended to be larger, and the mean neointimal area at the 8-month follow-up was significantly larger in less calcified lesions compared to heavily calcified lesions. As a result, the mean late lumen area loss was significantly larger in lesions with calcium arcs of 0° and in the first and second quadrants than in those with calcium arcs in the third and fourth quadrants (2.8±7.2, 1.3±5.6, 0.6±5.9, 1.2±5.4, -0.8±5.2 mm(2), respectively; p<0.001). SENSs continued to enlarge with intimal proliferation over 8months in all lesions. Although arterial calcium affected the degree of chronic stent expansion during the follow-up period, neointimal proliferation was smaller in heavily calcified lesion compared to less calcified lesion following SENS implantation.

Impact of intravascular ultrasound findings on long-term patency after self-expanding nitinol stent implantation in the iliac artery lesion.

Although intravascular ultrasound (IVUS) predictors of stent patency for the coronary artery lesion have been established, little is known about IVUS predictors of stent patency for the aorto-iliac artery lesion. We analyzed 154 lesions of 122 patients who underwent stent implantation for iliac artery lesions. Quantitative and qualitative IVUS analyses were performed for pre- and post-procedural IVUS imaging in all lesions. Target lesion revascularization (TLR) was defined as clinically driven revascularization with >50 % angiographic stenosis of the target lesion. The mean follow-up period was 39 ± 16 months. TLRs were performed in 13 lesions (8.4 %). Post-procedural minimum stent area (MSA) was significantly smaller in the TLR group compared to the no-TLR group (16.0 ± 5.8 vs. 25.6 ± 8.5 mm(2), p < 0.001). Stent edge dissection was frequently observed in the TLR group compared to the no-TLR group (53.8 vs. 24.1 %, p = 0.04). Multivariate analysis revealed that post-procedural MSA (OR = 0.76, p < 0.01) and stent edge dissection (OR = 10.4, p < 0.01) were independent IVUS predictors of TLR. Receiver-operating characteristic analysis identified post-procedural MSA <17.8 mm(2) as the optimal cut-point for the prediction of TLR (AUC = 0.846). Post-procedural MSA and stent edge dissection could predict long-term stent patency in the iliac artery lesion. Our results propose that adequate stent enlargement without edge dissection might be important to reduce TLR in the iliac artery lesion.

TCT-537 Long-term Outcomes of Self-Expanding Nitinol Stent Implantation for Chronic Total Occlusion of the Superficial Femoral and Proximal Popliteal Artery

Although recent guideline show expanded indication of endovascular therapy (EVT) for superficial femoral and proximal popliteal artery (SFPA) lesion, only secondary patency rate after self-expanding nitinol stent implantation is comparable for vein-graft bypass. Long-term outcomes are necessary for

Five‐year outcomes of self‐expanding nitinol stent implantation for chronic total occlusion of the superficial femoral and proximal popliteal artery

To investigate the 5-year patency rates and predictors of restenosis after self-expanding nitinol stent implantation for chronic total occlusion (CTO) in superficial femoral and proximal popliteal artery (SFPA) lesions. Outcomes and long-term patency rates after self-expanding nitinol stent for CTO in the SFPA lesions have not been clarified. From January 2004 to December 2009, 861 serial arteriosclerosis obliterans patients, 1,017 limbs, underwent endovascular therapy with implantation of a self-expanding nitinol stent for SFPA lesions at four institutions in Japan. Of the cohort, 352 patients, 383 limbs, had self-expanding nitinol stents implanted for CTOs in the SFPA and were followed for 5 years. We retrospectively investigated patency rate and multivariate predictors associated with restenosis. Mean age was 72 ± 9 years and 31% were female patients. In total, 58% of the patients had diabetes mellitus and 25% were patients with critical limb ischemia. Occluded length was 194 ± 89 mm, mean total stent length was 198 ± 7 mm, and mean stent diameter was 7.1 ± 0.9 mm. Five-year primary and secondary patency rates were 51.8 and 79.5%, respectively, and the rates of freedom from bypass surgery, major or minor amputation, and all-cause death were 96.1, 96.2, and 78.4%, respectively. Female gender (odds ratio, 1.95; P = 0.0051) and mean stent diameter (odds ratio, 0.77; P = 0.0324) were factors strongly associated with restenosis. Women and patients requiring small stents failed to maintain primary patency when treated with self-expanding nitinol stents for CTO lesions in the SFPA. Although primary patency was low, the secondary patency rate was acceptable.

Mid-term Outcomes After Self-expanding Nitinol Stent Implantation for TASC II Type D Lesions of The Superficial Femoral Artery

Mid-term Outcomes After Self-expanding Nitinol Stent Implantation for TASC II Type D Lesions of The Superficial Femoral Artery

Impact of Post-Procedural Intravascular Ultrasound Findings on Long-Term Results Following Self-Expanding Nitinol Stenting in Superficial Femoral Artery Lesions

Previous intravascular ultrasound (IVUS) studies have reported that a tiny reference cross-sectional area (CSA), stent under-expansion, stent asymmetry, stent edge dissection, and tissue protrusion are associated with target lesion revascularization (TLR) after coronary intervention. In the lower limb, however, it has not been reported that these findings correlate with TLR after endovascular therapy (EVT). A total of 236 consecutive superficial femoral artery (SFA) lesions in patients who underwent IVUS after self-expanding nitinol stent implantation, were analyzed. Stent expansion ratio was calculated as minimum stent CSA/reference lumen CSA, radial stent symmetry index as minimum/maximum stent diameter, and axial stent symmetry index as minimum/maximum stent CSA. TLR was defined as clinically driven revascularization with ≥75% restenosis of the target lesion. The mean follow-up period was 34±15 months. TLR were performed in 42 lesions (17.8%). There were no significant differences in stent expansion ratio, stent symmetry indices, and tissue protrusion between the TLR and no-TLR groups. Multivariate analysis indicated that total stent length (odds ratio [OR], 1.004; P<0.05), distal reference CSA (OR, 0.91; P<0.01), and stent edge dissection (OR, 3.51; P<0.01) were independent predictors of TLR. Stent implantation in tiny vessels and stent edge dissection in SFA lesions are indicators of high risk of TLR. Post-procedural stent under-expansion and stent asymmetry, however, were not associated with TLR.

TCT-601: Midterm Outcomes of S.M.A.R.T. Self-Expanding Nitinol Stent Implantation for Chronic Total Occlusion of Superficial Femoral Artery

TCT-601: Midterm Outcomes of S.M.A.R.T. Self-Expanding Nitinol Stent Implantation for Chronic Total Occlusion of Superficial Femoral Artery

How to Interpret Data from the Superficial Femoral Artery Stenting Trials and Registries

Recent advances in endovascular technologies have made catheter-based interventions a preferred treatment strategy in patients with intermittent claudication or ischemic rest pain of the lower extremity. Although the current body of literature is inundated with clinical reports favoring countless endovascular devices and treatment techniques for femoropopliteal occlusive disease, analysis of available clinical reports regarding femoropopliteal lesions can be an overwhelming undertaking. In this report, we examine various challenges associated with data interpretation of clinical literature on endovascular treatment of femoropopliteal occlusive disease. Particular attention is focused on prospective randomized trials and clinical registries evaluating treatment efficacy of self-expanding nitinol stent implantation in femoropopliteal lesions. Prospective trials on the efficacy of drug-eluting stent placement and covered stent implantation of the superficial femoral artery are also discussed. Understanding current literature related to prospective randomized trials on femoropopliteal disease interventions is important to formulate an optimal treatment strategy based on appropriate patient selection and disease stratification so that successful treatment outcome can be achieved.

In-hospital Costs of Self-Expanding Nitinol Stent Implantation versus Balloon Angioplasty in the Femoropopliteal Artery (The VascuCoil Trial)

Although several prospective studies have examined the safety and efficacy of stent placement for femoropopliteal arterial disease, the current cost of these procedures is unknown. To estimate and compare hospital costs associated with conventional balloon angioplasty (percutaneous transluminal angioplasty [PTA]) and stent placement for patients with symptomatic peripheral arterial disease, the authors performed a prospective economic evaluation in conjunction with the Intracoil Femoropopliteal Stent Trial (VascuCoil). Between May 1997 and December 1999, 266 patients with stenotic or occluded superficial femoral or popliteal arteries were prospectively randomized to treatment with the IntraCoil stent or PTA. Detailed resource use and cost data for each patient's initial revascularization procedure and ensuing hospitalization were collected and analyzed on an intention-to-treat basis. Compared with conventional balloon angioplasty, stent placement did not improve clinical outcomes but increased procedure duration, equipment costs, and physician services. As a result, initial hospital costs were approximately 3,500 dollars higher for patients randomized to the IntraCoil stent, compared with PTA (8,435 dollars vs 4,980 dollars; P < .001). As performed in the VascuCoil trial, primary stent placement for femoropopliteal disease did not improve clinical outcomes but increased initial treatment costs by more than 3,000 dollars. Because there were no substantial differences in subsequent clinical outcomes between the two treatments, it is unlikely that these increased initial costs would be offset by savings in follow-up costs. These findings suggest that a strategy of routine stent implantation for patients undergoing femoropopliteal PTA is not optimal on economic grounds and that PTA with provisional stent implantation is preferred.