Multicenter randomized prospective trial comparing a pre-cuffed polytetrafluoroethylene graft to a vein cuffed polytetrafluoroethylene graft for infragenicular arterial bypass. Randomized clinical trial of distal anastomotic interposition vein cuff in infrainguinal polytetrafluoroethylene bypass grafting. Does an adjuvant AV-fistula improve the patency of a femorocrural PTFE bypass with distal vein cuff in critical leg ischaemia?--a prospective randomised multicentre trial. Prospective randomised trial of distal arteriovenous fistula as an adjunct to femoro-infrapopliteal PTFE bypass. Randomized trial comparing infrainguinal polytetrafluoroethylene bypass grafting with and without vein interposition cuff at the distal anastomosis. The Joint Vascular Research Group. Early results of a prospective randomized trial of spliced vein versus polytetrafluoroethylene graft with a distal vein cuff for limb-threatening ischemia. Prospective randomized study on bilateral above-knee femoropopliteal revascularization: Polytetrafluoroethylene graft versus reversed saphenous vein. PTFE bypass to below-knee arteries: distal vein collar or not? A prospective randomised multicentre study. Dacron vs. polytetrafluoroethylene grafts for femoropopliteal bypass: a prospective randomised multicentre trial.
Poor patency of synthetic grafts for infragenicular revascularization has led to use of distal vein patches or cuffs. The aim of this study was to compare the distally widened Distaflo PTFE graft, which mimics a vein cuff, with a PTFE graft with distal vein modification. In this prospective, randomized, multicenter trial we compared use of a precuffed PTFE graft wit that of PTFE grafts with distal vein modification for infragenicular revascularization in patients with critical limb ischemia without saphenous vein. Study end points were primary and secondary patency and limb salvage rates at 2 years. From January 28,1999 to November 1, 2000, 104 patients were enrolled in 10 North American centers. Thirteen were excluded for protocol violation. Ninety-one bypasses were performed in 89 patients with a mean age of 73 years (range 47-90). By randomization, 47 bypasses were done with the precuffed graft and 44 with PTFE graft with vein cuff. Both groups were comparable for comorbidities and operative variables, except for a higher incidence of acute ischemia in the precuffed group (19% vs. 4.5%, p = 0.03). Bypass was a redo procedure in 53% and was performed at the infrapopliteal vessels in 79%. Operative mortality was 2.2% (2/91). Mean follow-up was 14 months (range 1-30). At 1 and 2 years, primary patency was 52% and 49% for the precuffed group and 62% and 44% for the vein cuffed group, respectively (p = 0.53). At 1 year and 2 years, the limb salvage rate was 72% and 65% for the precuffed group and 75% and 62% in the vein cuffed group (p = 0.88). Although numbers are small and follow-up short, this midterm analysis shows similar results for the Distaflo precuffed grafts and PTFE grafts with vein cuff. A precuffed graft is a reasonable alternative conduit for infragenicular reconstruction in the absence of saphenous vein and provides favorable limb salvage. The aim was to examine the effect of a Miller vein cuff at the distal anastomosis on the medium- to long-term patency and limb salvage rates of femoral to above-knee and femoral to below-knee popliteal artery polytetrafluoroethylene (PTFE) bypasses.
                This study involved extended follow-up of the original cohort of patients included in a previously reported multicentre randomized clinical study. Outcome measures were bypass graft patency and limb salvage.
                Two hundred and sixty-one bypass operations were originally randomized. For this study, full data were available on 235 (120 with a Miller cuff, 115 without). The cumulative 5-year patency rate for above-knee bypasses with a Miller cuff was 40 per cent, compared with 42 per cent for non-cuffed bypasses (P = 0.702). The cumulative 3-year patency rate for below-knee bypasses with a Miller cuff was 45 per cent, compared with 19 per cent for non-cuffed bypasses (P = 0.018). A Miller cuff had no significant effect on limb salvage for above-knee or below-knee bypasses.
                Three-year patency rates of femoral to below-knee popliteal PTFE bypasses were improved by a Miller cuff. Miller cuffs had no effect on patency rates for femoral to above-knee popliteal bypasses at 5 years and did not improve limb salvage in either group.
                Copyright 2004 British Journal of Surgery Society Ltd. A lack of suitable veins can cause serious problems when attempting to revascularise critically ischaemic legs. Prosthetic grafts have much worse patency in the femocrural position, despite the use of distal anastomotic cuffs. The use of adjuvant AV-fistula at the distal anastomosis should increase the graft flow above the thrombotic threshold velocity and thus increase prosthetic graft patency.
                The aim of the study was to evaluate the benefit of an adjuvant AV-fistula on the patency of a femorocrural PTFE bypass with a distal vein cuff.
                This prospective randomised multicentre trial was conducted in four centres. A total of 59 patients with critical leg ischaemia and no suitable veins for grafting were randomised to receive a femocrural PTFE bypass and distal vein cuff, with or without an adjuvant AV-fistula. Thirty-one patients were randomised to the AV-fistula group (AVFG) and 28 to the control group (CG). Six patients were lost to follow-up during the 2-year study time.
                There were six immediate occlusions in each treatment group, but half of these were saved by re-operation. The mean postoperative ankle-brachial index (ABI) was 0.85 in the AVFG and 0.94 in the CG. The primary and secondary patency rate at 2 years was 29 and 40% for the AVFG and 36 and 40% for the CG (NS). Leg salvage at 2 years was 65 and 68%, respectively (NS).
                Adjuvant AV-fistula does not improve the patency of a femorocrural PTFE bypass with a distal vein cuff. To compare graft patency and limb salvage rate following femoro-infrapopliteal bypass using ePTFE grafts with and without the addition of adjuvant arterio-venous fistula.
                A prospectively randomised controlled trial.
                Patients referred to two teaching hospital vascular surgery units in the U.K. for the treatment of critical limb ischaemia.
                Eighty-seven patients (M:F; 2.3:1) undergoing 89 femoro-intrapopliteal bypass operations with ePTFE grafts for critical limb ischaemia were randomly allocated to have AVF included in the operative procedure (n = 48) or to a control group without AVF (n = 41). An interposition vein-cuff was incorporated at the distal anastomosis in all patients.
                The cumulative rates of primary patency and limb salvage at 1-year after operation for patients with AVF were 55.2% and 54.1% compared to 53.4% and 43.2%, respectively, for the control group. The differences between the AVF and control groups did not reach statistical significance, in terms of either graft patency or limb salvage, at any stage after operation (Log-Rank test).
                AVF confers no additional significant clinical advantage over interposition vein cuff in patients having femoro-infrapopliteal bypass with ePTFE grants for critical limb ischaemia. A multicenter randomized prospective study was undertaken to determine whether an interposition vein cuff improved the short-term and medium-term patency and limb salvage rates of femoral-above-knee and femoral-below-knee popliteal artery polytetrafluoroethylene (PTFE) bypass procedures.
                Two hundred sixty-one bypass operations were randomized (133 to vein cuff and 128 to no vein cuff). One hundred fifty grafts were to the above-knee popliteal artery, 96 to the below-knee popliteal artery, and 15 to tibial vessels. The median follow-up was 617 days.
                The 12-month patency rates for cuffed and uncuffed above-knee popliteal artery PTFE bypass grafts were 80% and 84%, and the 2-year patency rates were 72% and 70%, respectively. The patency rates for bypass grafts to the below-knee popliteal artery at 12 months were 80% and 65% and at 2 years 52% and 29%, respectively (p = 0.03). At the below-knee site, this was reflected in 24-month difference in limb salvage rates of 84% and 62%, respectively (p = 0.08).
                There was no improvement in the patency rate with the use of a distal anastomosis interposition vein cuff in femoral-above-knee popliteal PTFE bypass grafts, but there was a statistically significant advantage when PTFE bypass grafts were anastomosed to the popliteal artery below the knee. Single-piece vein remains the conduit of choice in patients who need bypass grafting for limb salvage. When this option is not available, two of the remaining options are prosthetic bypass graft or several segments of vein spliced together. In this study, we compare spliced vein bypass grafting versus polytetrafluoroethylene grafting with a distal vein cuff in patients with limb-threatening ischemia.
                Between 1996 and 2000, 39 bypass grafting procedures in 36 patients were performed for limb-threatening ischemia. These procedures were prospectively randomized to either spliced vein bypass grafting (spliced group, 19 bypass grafts) or polytetrafluoroethylene grafting with a distal vein cuff (cuff group, 20 bypass grafts). All the patients in the cuff group underwent anticoagulation therapy with warfarin sodium after surgery. The inclusion criteria included: no single-piece vein option for bypass grafting, adequate vein for splice, no composite sequential option, and limb-threatening ischemia. The demographics were similar between the two groups.
                The primary patency rate at 2 years was 44% and 49% for the spliced and cuff groups, respectively. In the spliced group, seven of 19 bypass grafts underwent revision in the follow-up period, and two of 20 cuffed bypass grafts were successfully revised. The secondary patency rate was 87% and 59% (P <.05), with limb salvage rates of 94% and 85% for spliced and cuff groups, respectively. Four patients in the spliced vein group needed reoperation for wound complications related to vein harvest. One polytetrafluoroethylene graft needed removal for infection. Two early mortalities occurred in the spliced group, one from myocardial infarction and one from stroke. The overall survival rate at 2 years between the two groups was 67% and 100% for the spliced and cuff groups, respectively (P <.05).
                Although this is a preliminary report, it appears that both spliced vein bypass grafting and polytetrafluoroethylene bypass grafting with a distal vein cuff produce acceptable limb salvage rates. The secondary patency rate for spliced vein is better, but these bypass grafts more often need revision or reoperation for wound complications. Some controversy exists as to whether polytetrafluoroethylene (PTFE) is equivalent to reversed saphenous vein (SV) as bypass graft material for above-knee femoropopliteal revascularization. We compared the 5-year patency rate with reversed SV and PTFE grafts in patients with claudication who underwent bilateral above-knee femoropopliteal revascularization.
                Between January 1994 and December 1997, 51 patients (102 limbs) with bilateral disabling claudication due to superficial femoral artery occlusion underwent above-knee femoropopliteal bypass grafting, with SV in one limb and PTFE graft in the other limb. Patients were randomly selected for sequential surgical treatment with either SV-PTFE or PTFE-SV. Kaplan-Meier analysis was used to estimate patency rate, and various factors were analyzed to ascertain any association with revascularization failure.
                There was no perioperative (30 day) limb loss or death, but five late deaths (late survival rate, 90%). Mean follow-up was 59 months. In the SV group, three bypass grafts failed, requiring repeat operation in only one patient. In the PTFE group, eight bypass grafts failed, leading to five repeat operations. There was no statistically significant difference in primary "assisted" patency rate for the two grafts: 100%, 98%, and 94% for SV grafts, and 96%, 84%, and 84% for PTFE grafts (P =.09), after 1, 3, and 5 years, respectively.
                The overall results of this randomized study show that SV and PTFE grafts have a statistically comparable patency rate when used above the knee in patients with claudication. Use of SV, however, leads to fewer occlusions and repeat operations. Patency and limb salvage after synthetic bypass to the arteries below-knee are inferior to that which can be achieved with autologous vein. Use of a vein collar at the distal anastomosis has been suggested to improve patency and limb salvage, a problem that is analysed in this randomised clinical study.
                Patients with critical limb ischaemia undergoing polytetrafluoroethylene (PTFE) bypass to below-knee arteries were randomly either assigned a vein collar or not in two groups - bypass to the popliteal artery below-knee (femoro-popliteal below-knee (FemPopBK)) and more distal bypass (femoro-distal bypass (FemDist)). Follow-up was scheduled until amputation, death or at most 5 years, whichever event occurred first.
                In the FemPopBK and in the FemDist groups, 115/202 and 72/150 were randomised to have a vein collar, respectively. Information was available for 345 of 352 randomised patients (98%). At 3 years, primary patency was 26% (95% confidence interval (CI) 18-38) with a vein collar and 43 (33-58) without a vein collar for femoro-popliteal bypass and 20 (11-38), and 17 (9-33) for femoro-distal bypass, respectively. The corresponding figures for limb salvage were 64 (54-75) and 61 (50-74) for femoro-popliteal bypass, and 59 (46-76) and 44 (32-61) for femoro-distal bypass with and without a vein collar, respectively. Log-rank-test for the whole Kaplan-Meier life table curve showed no statistically significant differences with or without vein collar primary patency: p = 0.0853, p = 0.228; secondary patency: p = 0.317, p = 0.280; limb salvage: p = 0.757, p = 0.187 for FemPopBK and FemDist, respectively. The use of a vein collar did not influence patency or limb salvage.
                This study failed to show any benefit for vein collar with PTFE bypass to a below-knee artery.
                Copyright (c) 2010 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved. To compare the patency of PTFE (Polytetrafluoroethylene) and unsealed knitted Dacron femoro-popliteal bypasses.
                Multi-centre prospective randomised trial.
                Of 203 patients randomised, 194 were included in the final analysis (103 Dacron grafts and 91 PTFE grafts). The median follow-up was 36 months (range: 6-72 months); the distal anastomosis was above-knee in 141 and below-knee in 53 cases. Univariate comparisons of patency were made by the Kaplan-Meier method, multivariate calculations on the effects of covariables by a Cox regression analysis.
                There was no difference regarding primary and secondary patency or limb salvage between Dacron and PTFE. The primary 3-year patency for Dacron grafts was 64% (95% confidence interval [C.I.] 55-74%) and for PTFE grafts 61% (C.I. 49-72%). The corresponding 3-year secondary patency was 81% (C.I. 73-89%) and 75% (C.I. 65-86%) respectively, the limb salvage rate 90% (C.I. 84-96%) and 91% (C.I. 84-97%). Upon multivariate analysis below-knee anastomosis was the principal independent predictor of primary graft failure (risk ratio 1.7 [C.I. 1.05-2.8]), impaired secondary patency was associated with infragenicular bypass (risk ratio 3.3 [C.I. 1.8-6.3]) and distal gangrene (risk ratio [C.I. 1.01-3.8]p=0.048), major amputation was independently predicted by below-knee bypass, tissue necrosis, and poor run-off index.
                PTFE and Dacron are equally suitable for femoro-popliteal bypass.
There is some evidence that a vein cuff at the distal anastomosis site improves primary graft patency rates for below knee PTFE graft, but this does not reduce the risk of limb loss. Evidence for this beneficial effect of vein cuffed PTFE grafts is weak and based on an underpowered trial. Pre-cuffed PTFE grafts have comparable patency and limb salvage rates to vein cuff PTFE grafts. The use of spliced veins improved secondary patency but this did not translate into improved limb salvage. The use of an AVF alone showed no added benefits. A large study with a specific focus on below knee vein cuff prosthetic grafts, including PTFE, is required.