nitinol and Atherosclerosis

The performance of paclitaxel-coated balloon (PCB) or primary bare nitinol stent (BNS) versus uncoated balloon angioplasty (UCB) for femoropopliteal artery disease and the relative efficacy and safety of PCB versus BNS are still debated.. A meta-analysis of trials in which patients were randomly assigned to PCB versus UCB or BNS versus UCB was performed, as well as an indirect comparison of PCB versus BNS, with UCB common comparator. The primary endpoint was target lesion revascularization (TLR); secondary endpoints were restenosis, death and amputation.. In total, 1464 patients were assigned to revascularization with PCB versus UCB (n = 441) or BNS versus UCB (n = 1023). Treatment with PCB versus UCB reduced the risk of TLR (odds ratio [95% confidence interval] = 0.29 [0.15-0.56], p < 0.001) and restenosis (0.31 [0.19-0.51], p < 0.001) without affecting mortality (1.05 [0.41-2.71], p = 0.92) or amputation (0.68 [0.04-10.31], p = 0.78). BNS versus UCB therapy reduced the risk of TLR (0.46 [0.27-0.80], p = 0.006) and restenosis (0.51 [0.34-0.77], p = 0.02) without affecting mortality (2.08 [0.93-4.66], p = 0.07) or amputation (0.84 [0.30-2.35], p = 0.74). The indirect comparison found no difference with PCB versus BNS in the risk of TLR (0.63 [0.26-1.48] p = 0.29), restenosis (0.60 [0.32-1.15], p = 0.13) death (0.50 [0.05-4.82], p = 0.55) or amputation (0.80 [0.04-15.63], p = 0.66).. In atherosclerotic disease of femoropopliteal artery, both PCB and BNS therapy have superior antirestenotic efficacy to UCB, without safety issues. At indirect comparison, PCB and BNS may have comparable antirestenotic efficacy and safety.

Topics: Alloys; Angioplasty, Balloon, Coronary; Atherosclerosis; Coated Materials, Biocompatible; Femoral Artery; Humans; Myocardial Revascularization; Paclitaxel; Popliteal Artery; Randomized Controlled Trials as Topic; Stents; Treatment Outcome

To assess safety and efficacy of the S.M.A.R.T. Vascular Stent System (Cordis Corp, Fremont, California) in obstructive superficial femoral artery (SFA) disease.. The single-arm, multicenter STROLL study (S.M.A.R.T. Nitinol Self-Expanding Stent in the Treatment of Obstructive Superficial Femoral Artery Disease) included 250 patients (250 lesions in SFA or proximal popliteal artery). The efficacy endpoint was primary patency defined by freedom from binary restenosis (peak systolic velocity ratio > 2.5) as derived by duplex ultrasound plus clinically driven target lesion revascularization (TLR) at 12 months.. Mean age of patients was 67.7 years ± 10.3; 47.2% of patients had diabetes; distribution of Rutherford/Becker classes 2, 3, and 4 was 45.8%, 51.4%, and 2.8%. Mean lesion length and reference vessel diameter were 77.3 mm ± 35.3 and 4.9 mm ± 0.7, respectively (23.6% cases with total occlusions). The 30-day freedom from major adverse events (death, index limb amputation, clinically driven TLR) was 100%. The 1-year primary patency was 81.7% by Kaplan-Meier estimate. The presence of diabetes or total occlusion had no effect on primary patency. Ankle-brachial index was 0.4-0.8 in 84.6% of patients at baseline and improved to > 0.8 in 81.0% of patients at 12 months. The proportion of patients in Rutherford/Becker class 3-4 was reduced from 54.2% at baseline to 8.0% at 12 months. Four patients (2.0%) experienced single-stent strut fracture (type I) at 1 year, without associated loss of stent patency.. The S.M.A.R.T. Vascular Stent System proved to be safe and effective for endovascular treatment of obstructive SFA and proximal popliteal artery disease, based on 1-year vessel patency and associated hemodynamic and clinical improvements.

Topics: Aged; Alloys; Atherosclerosis; Constriction, Pathologic; Female; Femoral Artery; Follow-Up Studies; Humans; Male; Peripheral Arterial Disease; Stents; Treatment Outcome; Ultrasonography, Interventional

To evaluate the long-term efficacy and integrity of the PROTEGE EverFlex stent in superficial femoral artery (SFA) lesions in symptomatic patients with peripheral artery disease (PAD).. A prospective, multicenter, nonrandomized study enrolled 151 subjects (111 men; mean age 67.8 years, range 42-93) undergoing percutaneous treatment of de novo, restenotic, or reoccluded SFA lesions between August 11, 2006, and June 26, 2007. Subjects were scheduled to receive a single stent and be evaluated through 12 months following the implant procedure. Occlusions were present in 40% of the patients. Mean lesion length was 96.4 mm (range 10-150).. A total of 161 stents (158 EverFlex) were implanted in the 151 patients: single stents in 93.4% (141/151) and a second stent in 6.6% (10/151). One-year follow-up information was available for 88.7% (134/151) of the study participants; of the remaining 17 subjects, 6 subjects withdrew from the study, 2 were lost to follow-up, and 9 died. Freedom from restenosis data were available for 99.3% (133/134) of the subjects who completed a 12-month follow-up visit. The mean Rutherford classification fell from 2.8+/-0.8 (range 1-5) at baseline to 0.6+/-1.1 (range 0-5) at 12 months. The mean ankle-brachial index rose from 0.6+/-0.2 (range 0-1.4) at baseline to 0.9+/-0.2 (range 0-1.2) at 12 months. The rates for freedom from >50% restenosis at 6 and 12 months were 91.3% (95% CI 84.9% to 95.2%) and 72.2% (95% CI 63.8% to 79.6%), respectively. The freedom from target lesion revascularization rate at 12 months was 79.1% (95% CI 71.2% to 85.6%). The 1-year stent fracture rate was 8.1% (95% CI 4.0% to 14.4%).. The high freedom from >50% restenosis and low fracture rate at 12 months suggests that the PROTEGE EverFlex stent offers a safe and acceptably efficacious means of treating SFA lesions in symptomatic subjects with PAD.

Topics: Adult; Aged; Aged, 80 and over; Alloys; Angioplasty, Balloon; Atherosclerosis; Equipment Design; Female; Femoral Artery; Follow-Up Studies; Graft Occlusion, Vascular; Humans; Male; Middle Aged; Peripheral Vascular Diseases; Stents; Time Factors; Treatment Outcome

To review clinical outcomes of patients with chronic limb ischemia and TASC type C lesions treated with sirolimus-eluting versus bare SMART nitinol self-expanding stents.. Data were obtained from a randomized, multicenter, double-blinded study conducted in 2 phases. All 93 patients had chronic limb ischemia and superficial femoral artery (SFA) occlusions or stenoses (average lesion length 8.3 cm). In total, 47 patients (31 men; mean age 66.3+/-9.1 years, range 50-84) received the sirolimus-eluting SMART stent and 46 patients (36 men; mean age 65.9 +/-10.8 years, range 38-83) received a bare SMART nitinol stent. Both groups were followed for a mean 24 months.. Both the sirolimus-eluting and the bare SMART stents were effective in revascularizing the diseased SFA and in sustaining freedom from restenosis. For both types of stents, improvements in ankle-brachial indices (ABI) and symptoms of claudication were maintained over 24 months (median 24-month ABI 0.96 for the sirolimus group versus 0.87 for the bare stent group, p>0.05). At 24 months, the restenosis rate in the sirolimus group was 22.9% versus 21.1% in the bare stent group (p>0.05). The cumulative in-stent restenosis rates according to duplex ultrasound were 4.7%, 9.0%, 15.6%, and 21.9%, respectively, at 6, 9, 18, and 24 months; the rates did not differ significantly between the treatment groups. The TLR rate for the sirolimus group was 6% and for the bare stent group 13%; the TVR rates were somewhat higher: 13% and 22%, respectively. Mortality rates did not differ significantly between the groups.. These data demonstrate that the sirolimus-eluting and the bare SMART stent are effective, safe, and free from restenosis in a majority of patients for up to 24 months. Because the restenosis rate in the bare stent group is unexpectedly low, no significant difference could be found between the sirolimus-eluting and the bare SMART stents.

Topics: Adult; Aged; Aged, 80 and over; Alloys; Angioplasty, Balloon; Anti-Bacterial Agents; Atherosclerosis; Blood Vessel Prosthesis Implantation; Coated Materials, Biocompatible; Double-Blind Method; Drug Carriers; Female; Femoral Artery; Humans; Kaplan-Meier Estimate; Male; Middle Aged; Prospective Studies; Prosthesis Failure; Recurrence; Safety; Sirolimus; Stents; Treatment Outcome

The Misago iliac stent has not been compared with other stents. This study aimed to evaluate the 2-year clinical outcomes between the Misago stent and other self-expandable nitinol stents for symptomatic chronic aortoiliac disease.. This retrospective, single-center observational study enrolled 138 patients (180 limbs; Rutherford classification, between categories 2 and 6) treated with a Misago stent (N.=41) or self-expandable nitinol stent (N.=97) between January 2019 and December 2019. The primary endpoint was patency for up to 2 years. The secondary endpoints were technical success, procedure-related complications, freedom from target lesion revascularization, overall survival, and freedom from major adverse limb events. Multivariate Cox proportional hazards analysis was used to investigate predictors of restenosis.. The mean follow-up duration was 710±201 days. The 2-year primary patency rate was comparable between the groups (Misago, 89.6% and self-expandable nitinol stent, 91.0%, P=0.883). The technical success rate was 100% in both groups, and procedure-related complications were equivalent between the groups (1.7% and 2.4%, respectively; P=0.773). Freedom from target lesion revascularization was not significantly different between the groups (97.6% and 94.4%, respectively; P=0.890). The overall survival rate and freedom from major adverse limb events were not significantly different between the groups (77.2% and 70.8%, respectively, P=0.209; 66.9% and 58.4%, respectively, P=0.149). Statin therapy was positively associated with primary patency.. The Misago stent for aortoiliac lesions demonstrated comparable and acceptable clinical results of safety and efficacy for up to 2 years compared with other self-expandable stents. Statin use predicted the prevention of patency loss.

Topics: Alloys; Atherosclerosis; Femoral Artery; Humans; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Peripheral Arterial Disease; Popliteal Artery; Prosthesis Design; Retrospective Studies; Stents; Time Factors; Treatment Outcome; Vascular Patency

To analyze the outcomes of Supera stent deployment in Chinese patients with atherosclerotic femoropopliteal artery (FPA) disease in a real-world setting.. This retrospective cohort study collected and analyzed the medical records of 246 consecutive patients who received Supera stents for FPA disease at the China Academy of Chinese Medical Sciences Xiyuan Hospital between February 2017 and December 2019. All study patients underwent balloon angioplasty and were treated with Supera stents (Abbott Vascular, Santa Clara, CA, USA). The primary outcome was the rate of primary patency 12 months after discharge.. The analyses included 246 consecutive patients and 260 lesions. The mean ± SD age was 73.2 ± 9.9 years and most patients (60.2%) were males. Of the 260 treated lesions, Supera stents were deployed in eight (3.1%) cases after a previous stent fracture. Critical limb ischemia was diagnosed in 87.3% of the limbs, and 84 (32.3%) and 83 (31.5%) cases were classified as TransAtlantic Inter-Society Consensus (TASC) C and D, respectively. Most of the lesions were in situ (80.8%) and located in the superficial femoral artery (45.0%) or the FPA (45.8%). The mean lesion length was 147.7 mm. Nominal deployment (-10 to 10% compression) was the most common deployment scenario (84.1%). The 1-year primary patency rate was 80.6%. Lesions that occurred as restenosis (odds ratio [OR]: = 3.34, 95% confidence interval [CI]: 1.03-10.85, P = 0.045) or in-stent restenosis (OR: = 2.88, 95% CI: 1.03-8.07, P = 0.045) were independently associated with occlusion or stenosis after stent deployment. No stent fracture was observed in this study.. Our study indicates that the use of Supera stents is feasible for the treatment of Chinese patients with FPA disease. The long-term results reveal high primary patency.

Topics: Aged; Aged, 80 and over; Alloys; Atherosclerosis; Constriction, Pathologic; Female; Femoral Artery; Humans; Male; Middle Aged; Peripheral Arterial Disease; Popliteal Artery; Prosthesis Design; Retrospective Studies; Risk Factors; Stents; Treatment Outcome; Vascular Patency

To evaluate efficacy, safety, and midterm patency of endovascular treatment of obstructive popliteal artery (PA) disease.. A retrospective evaluation of patients with atherosclerotic PA disease who underwent percutaneous transluminal balloon angioplasty and provisional stent, based on both conventional and dynamic angiographies, was conducted from June 2011 to June 2014. Forty-three patients were included in the study, and most patients had limited surgical revascularization options. Demographic characteristics, angiographic findings, interventional data, complications, vessel patency, limb salvage rates, and survival rates were analyzed.. The median lesion length was 5 cm with 72.1% having total occlusions. The second popliteal segment (P2) was involved most frequently (60.5%, n = 26). Critical limb ischemia was present in 69.8%. The technical success rate was 92.9% (42/43 limbs), with 29 cases requiring adjunctive nitinol stents after balloon angioplasty (47.6% based on conventional angiography, 21.4% based on dynamic angiography, and 4.8% additional stents based on dynamic angiography). Complications included thromboembolism (2.3%), perforation (2.3%), pseudoaneurysm (2.3%), and myocardial infarction (2.3%). Stent fracture was present in three cases (7.1%) during the mean follow-up period of 18.3 months. The baseline ankle-brachial index significantly improved after the intervention, from 0.49 ± 0.11 to 0.92 ± 0.14 (P < .01). The Rutherford-Becker class decreased from 3.95 ± 0.76 to 1.76 ± 0.95 (P < .01) at 12 months. The 1-year primary, primary-assisted, and secondary patency rates were 75.2% ± 6.8%, 82.4% ± 6.0%, and 89.9% ± 4.8%, respectively. The limb salvage and amputation-free survival rates at 12 months were 91.6% and 87.0%, respectively.. Balloon angioplasty with a provisional stent based on dynamic angiography is a feasible, safe, and effective therapy for patients with obstructive PA disease. Although the occurrence of stent fracture is still inevitable, patients with critical limb ischemia who have limited surgical options may get more benefits from the endovascular treatment of PA obstructive diseases.

Topics: Aged; Aged, 80 and over; Alloys; Amputation, Surgical; Angiography; Angioplasty, Balloon; Ankle Brachial Index; Atherosclerosis; China; Critical Illness; Female; Humans; Ischemia; Kaplan-Meier Estimate; Limb Salvage; Male; Popliteal Artery; Predictive Value of Tests; Proportional Hazards Models; Prosthesis Design; Retreatment; Retrospective Studies; Risk Factors; Stents; Survival Rate; Time Factors; Treatment Outcome; Vascular Patency

To evaluate the relationship between 1-year primary patency and lesion length in patients with femoropopliteal disease treated with bare nitinol stents.. The study was a retrospective analysis of a prospectively maintained multicenter database. Between January 2004 and December 2011, 1047 consecutive patients (mean age 72 years; 765 men) underwent femoropopliteal stenting with nitinol stents in 1373 limbs. The mean vessel diameter was 5.3±0.7 mm and the mean lesion length was 142±75 mm. One-year follow-up data were collected and analyzed to ascertain which lesion length would be expected to demonstrate a 1-year primary patency above the established 66% objective performance goal (OPG).. The lower limit of the 95% confidence interval (CI) for the unadjusted 1-year primary patency was >66% when the lesion length was ≤243 mm. After adjustment of the covariates to match those of the OPG-derived population, the 1-year primary patency decreased linearly with longer lesion length. The 1-year primary patency was 83.2% (95% CI 79.8% to 86.1%) for a 100-mm lesion length, 76.4% (95% CI 71.7% to 80.5%) for a 200-mm lesion length, and 70.7% (95% CI 62.4% to 77.7%) for a 300-mm lesion length. The maximum lesion length providing a 1-year primary patency significantly greater than 66% was calculated to be 263 mm.. The 1-year primary patency of femoropopliteal lesions treated with bare nitinol stents decreased linearly with longer lesion length. The maximum lesion length providing a higher patency rate than the OPG of 66% was ~25 cm.

Topics: Aged; Alloys; Atherosclerosis; Endovascular Procedures; Female; Femoral Artery; Humans; Male; Peripheral Arterial Disease; Popliteal Artery; Prosthesis Design; Retrospective Studies; Stents; Vascular Patency

Popliteal artery stenting is not routinely performed due to concerns related to the high mobility of the knee joint and the potential for external stent compression, fractures, and occlusion. Open bypass is traditionally considered the gold standard for popliteal artery atherosclerotic lesions. The Supera stent (IDEV Technologies Inc, Webster, Tex) was developed to provide superior radial strength, fracture resistance, and flexibility compared with laser-cut nitinol stents. This study represents the initial United States experience in the management of popliteal artery atherosclerotic disease with the Supera interwoven wire stent.. Patients undergoing stent implantation in the 20-month period after the 2008 Food and Drug Administration clearance were included. Medical records, radiographic imaging, and procedural data were examined. Procedural angiograms were classified according to Trans-Atlantic Inter-Society Consensus criteria. Patency and limb loss rates were calculated using Kaplan-Meier analysis.. A total of 39 stents were placed in 34 patients due to isolated popliteal artery occlusive disease. Clinical follow-up was a mean of 12.7 months (range, 0.2-33.7 months), and radiologic follow-up was a mean of 8.4 months (range, 0-26.8 months). Most patients had critical limb ischemia (CLI), with tissue loss (38.2%) or rest pain (35.3%) as the indication for intervention. In 20 patients (58.8%), the most distal end of the stent(s) landed in the below-the-knee popliteal segment, 12 (35.3%) landed in the above-the-knee segment, and two (5.9%) landed precisely at the knee. Other than angioplasty and stenting, 47% of patients did not receive any adjuvant concomitant therapy in the treated leg. Two patients underwent concomitant atherectomy of the popliteal segment. Primary, primary assisted, and secondary patency rates by duplex ultrasound imaging were 79.2%, 88.1% and 93%, respectively, by Kaplan-Meier estimates, with a mean stented length of 12 cm. Six instances of stent occlusion were noted, and six patients were identified with hemodynamically significant in-stent stenosis. Three patients sustained limb loss (8.8%), two related to uncontrolled infections, and one due to perioperative ischemic complications (both with patent stents at the time of limb loss). The overall mortality was 8.8% during the study period. Knee roentgenography was performed in all but one patient, and no stent fractures were identified.. Stenting of the popliteal artery using the Supera stent system appears to be safe and effective. The interwoven stent design may better serve areas under extreme mechanical stress. Our results with this highly diseased patient population justify a prospective trial in this subject.

Topics: Aged; Aged, 80 and over; Alloys; Amputation, Surgical; Angioplasty; Atherosclerosis; Critical Illness; Female; Hemodynamics; Humans; Intermittent Claudication; Ischemia; Kaplan-Meier Estimate; Male; Middle Aged; Multivariate Analysis; Popliteal Artery; Proportional Hazards Models; Prosthesis Design; Radiography; Retrospective Studies; Risk Factors; Stents; Time Factors; Treatment Outcome; Ultrasonography, Doppler, Duplex; United States; Vascular Patency

The histologic response to self-expanding stent implantation into advanced atherosclerotic lesions has not been systematically investigated. We tested the hypothesis of whether gradual expansion of advanced atherosclerotic plaques by self-expanding stents would be an appropriate method to seal atherosclerotic lesions without causing plaque disruption as is usually observed with balloon-expandable stents.. Twelve New Zealand white rabbits were fed an atherogenic diet (1% cholesterol) followed by arterial denudation and injection of washed autologous erythrocytes. Nitinol self-expanding stents of two different stent designs and strengths (n=12 for SX and n=12 for Micro-SX) were implanted into the previously formed lesions within the abdominal aorta six weeks following injection of erythrocytes. Four weeks following stent implantation, animals were sacrificed, specimens harvested and processed for histology. Histomorphometry was performed on stented and adjacent non-stented regions. Atherosclerotic lesions were composed of foam cells, cholesterol clefts and necrotic plaque. While SX stents showed an unfavourable outcome with respect to vessel remodelling and the percentage of uncovered stent struts, Micro-SX stents had fewer uncovered stent struts, less positive remodelling and less plaque injury.. Nitinol Micro-SX self-expanding stents might be a valuable approach to seal high risk atherosclerotic lesions.

Topics: Alloys; Animals; Aorta, Abdominal; Aortic Diseases; Atherosclerosis; Blood Vessel Prosthesis; Endothelium, Vascular; Prosthesis Design; Rabbits; Stents

To compare aortic intimal thickening of normal and hyperhomocysteinemic pigs (induced with a methionine-rich diet) following placement of a self-expanding nitinol stent.. Eighteen Macau pigs were used. They were older than eight weeks in age and had an average weight of 30 kg. Pigs were randomly divided into two groups. The first, Group C (control), was fed a regular diet, and the second group, Group M, was fed a methionine-rich diet for 30 days to induce hyperhomocysteinemia. The self-expandable nitinol stents were 25mm in length and 8 mm in diameter after expansion. Blood samples were collected to measure total cholesterol, triglycerides, HDL and homocysteine concentrations. All animals were subjected to angiography. Thirty days after the procedure, the animals were sacrificed, and the abdominal aorta was removed for histological and digital morphometry analysis.. Under microscopic evaluation, the intima was significantly thicker in Group C than in Group M. When groups were compared by digital morphometric analysis, intimal thickening of the vessel wall was higher in Group C than in Group M. There was no significant change in total cholesterol, triglycerides or HDL concentrations in either group. In group C the levels of plasma homocysteine ranged from 14,40 to 16,73 micromol/l; in Group M, plasma homocysteine levels ranged from 17.47 to 59.80 micromol/l after 30 days of a methionine-rich diet.. Compared to normal pigs, less intimal hyperplasia was observed in the abdominal aortas of hyperhomocysteinemic pigs thirty days after the insertion of a self-expandable nitinol stent.

Topics: Alloys; Animals; Aorta; Aorta, Abdominal; Atherosclerosis; Biocompatible Materials; Cholesterol, HDL; Coronary Restenosis; Diet, Atherogenic; Disease Models, Animal; Hyperhomocysteinemia; Hyperplasia; Random Allocation; Stents; Swine; Triglycerides; Tunica Intima

This analysis proposes safety and performance goals for prospective single-arm trials of bare nitinol stents to treat patients with debilitating claudication associated with femoropopliteal (FP) atherosclerotic lesions.. To date there have been no analyses of clinical trials data to set efficacy and safety benchmarks for new bare nitinol stents in the treatment of claudication from FP disease. Industry has been reluctant to sponsor studies of nitinol stents due to logistical barriers.. VIVA Physician's, Inc. (VPI) analyzed subject-level data from the PTA control arm of three randomized FDA device trials conducted by industry. Subjects with Rutherford category 2-4 claudication and FP lesion lengths 4-15 cm with 12 month duplex ultrasound (DUS) assessment were identified. These data were combined with the results of a survey of the medical literature (1990-2006) for similar subjects.. Analysis of the industry derived control arm PTA data identified 116 patients (mean lesion length 8.7 cm) with a 12 month DUS defined FP patency of 28%. A similar cohort of 191 patients was identified from the medical literature in which the 12-month vessel patency equaled 37%; from these combined patient cohorts, expected vessel patency for PTA was estimated to equal 33%.. Based on the PTA performance efficacy rate of 33% derived from industry clinical trial data and the medical literature, and the requirement that the bare nitinol stent 12-month efficacy performance goal be set to equal twice this rate, the patency efficacy goal equals 66%. Additional information is provided on safety and other reporting standards and stent integrity evaluation for bare metal stents.

Topics: Alloys; Angioplasty, Balloon; Atherosclerosis; Clinical Trials as Topic; Endpoint Determination; Femoral Artery; Guidelines as Topic; Humans; Intermittent Claudication; Peripheral Vascular Diseases; Popliteal Artery; Prospective Studies; Randomized Controlled Trials as Topic; Registries; Research Design; Sample Size; Severity of Illness Index; Stents; Treatment Outcome; Vascular Patency; Vascular Surgical Procedures

To evaluate the initial and mid-term results of a new self-expanding low strut profile nitinol stent for treatment of atherosclerotic lesions stenoses and occlusions in the superficial femoral artery (SFA).. In 8 patients (4 male, 4 female, mean age 74.8 +/- 8.8 years) with SFA lesions and non-satisfying results after PTA treatment alone, 10 self-expanding nitinol Xpert stents were deployed via a 4 F sheath. Stent characteristics and handling were graded by the interventionalist. Fontaine classification, duplex flow measurements and ankle brachial index (ABI) at rest and stress were taken prior and one day after stent placement. Patients were followed 3, 6 and 12 months after the procedure obtaining the same parameters at each appointment.. Initial stent treatment was successful in all patients. Stent handling and positioning were rated very good and safe. All patients improved clinically by at least one Fontaine stage (range before treatment: stage IIb to IV). The mean ABI at rest (stress) improved initially from 0.68 (0.70) to 1.07 (0.99). During a mean follow-up period of 8.3 months no case of clinically relevant in-stent stenosis was observed with stable values of ABI at rest and stress.. Treatment of SFA lesions using the 4F-compatible self-expanding nitinol Xpert stent is technically simple, safe and shows good initial and mid-term results.

Topics: Aged; Aged, 80 and over; Alloys; Angioplasty, Balloon; Arterial Occlusive Diseases; Atherosclerosis; Cohort Studies; Equipment Design; Female; Femoral Artery; Follow-Up Studies; Humans; Male; Middle Aged; Prospective Studies; Radiography; Stents

To test the feasibility of self-expanding drug-coated nitinol stents for prevention of restenosis in an animal model. Stent implantation in the carotid artery (CA) has been shown to be feasible for treatment of CA stenosis. Even though the restenosis rate in CA is reported to be lower than in the coronary and peripheral arteries, problems may arise with increasing numbers of treated patients and lengthier follow-up.. After predilatation with 8-mm balloons, 8 Goettinger minipigs were randomly selected to receive a sirolimus-eluting self-expanding nitinol stent (7 mm/80 mm) as well as the same stent without sirolimus/polymer coating in the right or left CA. Aspirin was given starting 3 days before the intervention and administered for an additional 4 weeks. Clopidogrel was administered for 10 days.. After 6 weeks, 2 subacute occlusions were observed in both groups. In the remaining vessels, the neointima was significantly reduced by sirolimus/polymer-coated stents (5.9+/-2.5 versus 0.7+/-1.0 mm2).. Sirolimus self-expanding nitinol stents may be an effective tool in reducing neointimal formation in CA.

Topics: Alloys; Angioplasty, Balloon, Coronary; Animals; Anti-Inflammatory Agents, Non-Steroidal; Aspirin; Atherosclerosis; Carotid Arteries; Clopidogrel; Coronary Angiography; Coronary Restenosis; Disease Models, Animal; Male; Polymers; Sirolimus; Stents; Swine; Ticlopidine; Time Factors; Ultrasonics

To compare quantitative and qualitative parameters obtained from digital subtraction angiography (DSA) with multislice computed tomographic angiography (MSCTA) in the follow-up of superficial femoral artery (SFA) stents.. Thirteen patients who had SMART stents implanted in the SFA were examined systematically with DSA and MSCTA (16-row scanner) at 6 months. Quantitative analysis and morphological assessment were performed on DSA images by an independent core laboratory, while the MSCTA images were analyzed by 2 radiologists in consensus. DSA measurements included stent length, minimal lumen diameter and reference diameter at mid stent and 5 mm either side of the stent, and percentage of stenosis. For MSCTA images, lumen area and the minimum, maximum, and mean diameters were also recorded. The images were analyzed qualitatively for diameter stenosis (<50%, 50% to 70%, 71% to 99%, and occlusion), bends, fractures, and calcifications.. There were no statistical differences between lengths of stented segments, diameter measurements, or percentages of stenosis from DSA and MSCTA images. The Bland-Altman method showed good agreement between the 2 methods of measurement. MSCTA detected in-stent proliferation with a diameter stenosis <50% in all 13 cases diagnosed on DSA (there was no stenosis >50%). There were no bends or stent fractures on either set of images. The agreement between DSA and MSCTA for the presence and grading of calcifications was moderate (kappa=0.5).. MSCTA provided quantitative and qualitative data comparable with DSA in the analysis of SFA nitinol stents.

Topics: Aged; Aged, 80 and over; Alloys; Angiography, Digital Subtraction; Atherosclerosis; Blood Vessel Prosthesis Implantation; Calcinosis; Female; Femoral Artery; Follow-Up Studies; Humans; Male; Middle Aged; Radiographic Image Interpretation, Computer-Assisted; Research Design; Severity of Illness Index; Stents; Tomography, X-Ray Computed; Treatment Outcome

To report the complications, rescue procedures, and consequences related to the use of an embolus protection filter during carotid artery stenting (CAS).. A retrospective review was undertaken of 72 patients (58 men; mean age 70.0+/-8.2 years, range 56-87) with extracranial atherosclerotic carotid stenosis who underwent 77 CAS procedures under filter protection. Filter-related events and rescue procedures according to each procedural step were retrospectively evaluated on CAS angiograms. In addition, neurological events and outcomes were also assessed.. CAS using a filter was successful in 99% of cases, and the overall rate of minor stroke (n=1), major stroke (0), or mortality (n=1) was 2.6% at 30 days. Filter placement was successful in all cases. However, arterial tortuosity made it difficult for a filter to pass through the stenosis in 1 case; this was overcome with an additional supportive wire (0.018-inch). Filter-related events were flow impairment in 6 (7.8%), filter wedging in the catheter tip in 4 (5.2%), vasospasm >50% narrowing in 7 (9.1%), filling defects within the filter membrane in 5 (6.5%), retrieval failure with the provided retriever in 3 (3.9%), and insecure retrieval without filter collapse in 2 (2.6%). Flow impairment caused drowsy mentality and impaired verbal response in 4, which resolved after prompt filter retrieval. All the cases of filter wedging were resolved with a catheter pulled down into the stented segment to separate the filter element from the catheter tip. Significant vasospasm and filling defects were spontaneously resolved in all cases after filter retrieval. Inability to pass a retriever catheter through a stent was overcome with curved 5-F catheter manipulation in all 3 cases.. The use of a filter during CAS may induce various angiographic or technical events at each step. For a severely stenotic and tortuous carotid lesion with difficult access, a filter may become trapped or irretrievable during flow arrest. Physicians should be aware of the preventive and rescue maneuvers to counter filter-related events, perhaps even considering another type of protection mechanism or carotid endarterectomy.

Topics: Aged; Aged, 80 and over; Alloys; Angioplasty, Balloon; Atherosclerosis; Blood Vessel Prosthesis Implantation; Carotid Stenosis; Endarterectomy, Carotid; Equipment Design; Equipment Failure; Female; Filtration; Humans; Intracranial Embolism; Male; Middle Aged; Radiography; Retrospective Studies; Risk Factors; Safety; Stents; Stroke; Treatment Outcome; Vascular Patency; Vasospasm, Intracranial

To assess the technical feasibility and efficacy of distal embolus protection with an intra-aortic filter during stent-graft repair in a patient diagnosed with a shaggy aorta.. In a 75-year-old man with a severely atherosclerotic thoracic aortic aneurysm, stent-graft repair was combined with transposition of the arch branches to the ascending aorta under thoracotomy. A filtration-type embolus protection device with a nitinol basket and polyester fabric was introduced through a 12-F sheath and opened in the supraceliac aorta during the stent-graft procedure; it was safely pulled back into the sheath after the stent-grafts were implanted. The stent-graft repair was successful, and abundant atheromatous debris was captured in the filter. Neither procedure-related embolic events nor neurological deficits were observed.. Use of the intra-aortic filter device to prevent distal embolism during thoracic stent-graft repairs may be feasible and efficacious in severely atherosclerotic patients.

Topics: Aged; Alloys; Aortic Aneurysm, Thoracic; Atherosclerosis; Blood Vessel Prosthesis; Blood Vessel Prosthesis Implantation; Contrast Media; Embolism; Feasibility Studies; Humans; Male; Prosthesis Design; Stents; Tomography, X-Ray Computed; Treatment Outcome

The purpose of this study was to evaluate the patentcy rates and physiological effectiveness of angioplasty and stenting as a primary therapy for superficial femoral (SFA), popliteal (POP), and tibial (TIB) arterial occlusive disease. Seventy-eight patients had stents placed in the infra-inguinal vessels between January 1, 2001, and July 31, 2004. We collected data on patient demographics, symptoms, as well as pre- and postprocedure ankle-brachial index (ABI) and angiographic findings. Patency rates at 6 months, 12 months, and 24 months were analyzed by life table methods. Thirty-one men and 47 women had a mean age of 68 years (range 36-94 years). Risk factors included diabetes in 50 per cent, hypertension in 79 per cent, smoking in 41 per cent, and end-stage renal disease in 10 per cent. The indications for intervention were claudication in 52 per cent and limb salvage in 48 per cent of patients. Stents were placed in the SFA in 54 patients (69%), in the POP in 15 patients (18%), and in the TIB artery in 6 patients (8%). Average follow-up was 11.2 months. The mean postprocedural increase in ABI was 0.29. The 6-month, 1-year, and 2-year primary patency rates were 83 per cent, 58 per cent, and 47 per cent, respectively. Limb salvage was achieved in 66 per cent of patients treated for limb-threatening ischemia. There was one major and three minor complications. Stenting of the infra-inguinal vessels has a low morbidity, high success rate, and acceptable patency and limb-salvage rates.

Topics: Adult; Aged; Aged, 80 and over; Alloys; Atherosclerosis; Female; Femoral Artery; Humans; Male; Middle Aged; Peripheral Vascular Diseases; Popliteal Artery; Prospective Studies; Stents; Tibial Arteries