Polytetrafluoroethylene versus human umbilical vein in above-knee femoropopliteal bypass: six-year results of a randomized clinical trial. Dacron or ePTFE for femoro-popliteal above-knee bypass grafting: short- and long-term results of a multicentre randomised trial. Human umbilical vein versus heparin-bonded polyester for femoro-popliteal bypass: 5-year results of a prospective randomized multicentre trial. Four years' results of a prospective, randomized clinical trial comparing polytetrafluoroethylene and modified human umbilical vein for below-knee femoropopliteal bypass. A prospective randomized trial comparing vein with polytetrafluoroethylene in above-knee femoropopliteal bypass grafting. Dacron vs. polytetrafluoroethylene grafts for femoropopliteal bypass: a prospective randomised multicentre trial. Prospective randomized study on bilateral above-knee femoropopliteal revascularization: Polytetrafluoroethylene graft versus reversed saphenous vein. Dacron or PTFE for above-knee femoropopliteal bypass. a multicenter randomised study. Heparin-bonded Dacron or polytetrafluorethylene for femoropopliteal bypass: five-year results of a prospective randomized multicenter clinical trial. Comparing vein with collagen impregnated woven polyester prosthesis in above-knee femoropopliteal bypass grafting. Randomized clinical trial of distal anastomotic interposition vein cuff in infrainguinal polytetrafluoroethylene bypass grafting.
In a prospective, randomized trial 6 mm polytetrafluoroethylene (PTFE) and 6 mm human umbilical vein (HUV) were compared in above-knee femoropopliteal bypass grafting. In claudicants a prosthetic graft was used intentionally, in limb-salvage cases only when autologous vein was insufficient. Ninety-six extremities were randomized (49 PTFE and 47 HUV). Operative indication was disabling claudication in 77 and limb salvage in 19 extremities. The two groups were comparable as to preoperative risk factors and operative and postoperative treatment. Median follow-up was 76 months (range 47 to 91 months), during which 23 patients died of nonrelated causes with functioning grafts. Thirty-eight grafts failed (33 because of occlusion and five for other reasons). At 6 years the primary patency rate was 38.7% in the PTFE group and 71.4% in the HUV group (p < 0.001). Corresponding rates for secondary patency at 6 years were 51.4% and 76.4% (p < 0.005). To compare expanded polytetrafluoroethylene (ePTFE) prosthesis and collagen-impregnated knitted polyester (Dacron) for above-knee (AK) femoro-popliteal bypass grafts.
                A prospective multicentre randomised clinical trial.
                Between 1992 and 1996, 228 AK femoro-popliteal bypass grafts were randomly allocated to either an ePTFE (n=114) or a Dacron (n=114) vascular graft (6mm in diameter). Patients were eligible for inclusion if presenting with disabling claudication, rest pain or tissue loss. Follow-up was performed and included clinical examination and duplex ultrasonography at all scheduled intervals. All patients were treated with warfarin. The main end-point of this study was primary patency of the bypass graft at 2, 5 and 10 years after implantation. Secondary end-points were mortality, primary assisted patency and secondary patency. Cumulative patency rates were calculated with life-table analysis and with log-rank test.
                After 5 years, the primary, primary assisted and secondary patency rates were 36% (confidence interval (CI): 26-46%), 46% (CI: 36-56%) and 51% (CI: 41-61%) for ePTFE and 52% (CI: 42-62%) (p=0.04), 66% (CI: 56-76%) (p=0.01) and 70% (CI: 60-80%) (p=0.01) for Dacron, respectively. After ten years these rates were respectively 28% (CI:18-38%), 31% (CI:19-43%) and 35% (CI: 23-47%) for ePTFE and 28% (CI: 18-38%), 49% (CI: 37-61%) and 49% (CI: 37-61%) for Dacron.
                During prolonged follow-up (10 years), Dacron femoro-popliteal bypass grafts have superior patency compared to those of ePTFE grafts. Dacron is the graft material of choice if the saphenous vein is not available. To compare long-term patency of Heparin-Bonded Dacron (HBD) and Human Umbilical Vein (HUV) vascular prostheses in above-knee femoro-popliteal bypass surgery.
                A prospective randomized multi-centre clinical trial.
                Femoro-popliteal bypasses were performed in 129 patients between 1996 and 2001. After randomization 70 patients received an HUV and 59 an HBD prosthesis. Patients were followed up every three months during the first postoperative year and yearly thereafter. The median follow-up was 60 months (range 3-96 months). Graft occlusions were detected by duplex scanning, angiography or surgical exploration.
                The cumulative primary patency rates were 79%, 66% and 58% at 1, 3 and 5 years postoperatively. Primary patency rates for HUV were 74%, 64% and 58% at 1, 3 and 5 years and 84%, 68% and 58% for HBD, respectively (log-rank test, p=0.745). Overall secondary patency rates were 82%, 72% and 61% at 1, 3 and 5 years postoperatively. The overall cumulative limb salvage at 5 years follow-up was 89% (CI 80%-91%) and was not dependent on graft type. Smoking (p=0.019), number of patent crural arteries (p=0.030) and previous cerebro-vascular events (p=0.030) were significant predictors of graft occlusion.
                There was no difference in long-term graft performance between HUV and HBD for above knee infrainguinal bypass. Polytetrafluoroethylene (PTFE) (Gore-Tex) and human umbilical vein (Biograft) arterial grafts were compared for below-knee femoropopliteal bypass grafting in a prospective randomized clinical trial. One hundred five patients (105 limbs) entered the trial. Seventy-six percent suffered from rest pain, ulceration, or gangrene. The median postoperative ankle-arm blood pressure index was 0.36. Twenty-three limbs had three patent tibial arteries, 46 limbs had two tibial arteries, 31 limbs had one patent artery, and five limbs had isolated popliteal segments. Thirty-four percent were repeat operations. Fifty-five patients were allocated to receive PTFE grafts and 50 to receive human umbilical vein grafts. The two groups were comparable as to preoperative risk factors and operative and postoperative treatment. During the first 4 years (maximum 1609 days) 40 PTFE grafts and 24 umbilical veins occluded. At 1 year the PTFE patency rate was 53% and at 4 years was 22%. For umbilical vein the corresponding figures were 74% and 42% (p = 0.005, Gehan test). During follow-up the incidence of PTFE failure was on the average 2.1 times higher than that of umbilical vein failure (95% confidence limits 1.2 to 3.4). Despite many clinical studies, there is still uncertainty as to whether venous material is superior to polytetrafluoroethylene for femoropopliteal reconstruction proximal to the knee joint. Supported by early satisfactory results with thin-walled, stretched polytetrafluoroethylene for suprageniculate bypass grafts, a prospectively randomized clinical trial was designed to evaluate the effectiveness of reversed saphenous vein in comparison with that of polytetrafluoroethylene in above-knee arterial reconstruction.
                In a 3-year period, 151 above-knee femoropopliteal bypass graft operations were performed in 136 patients (77 male, 59 female). The indication for operation was severe claudication in 120 cases, rest pain in 20 cases, and ulceration in 11 cases. For the bypass graft, a reversed saphenous vein was used in each of 75 cases, and a polytetrafluoroethylene prosthesis was used in each of 76 cases. Preoperative risk factors were diabetes (24%), a history of myocardial infarction (23%), and current status with respect to smoking (74%). There was no hospital mortality; 5% of patients had minor postoperative complications.
                After 2 years, the primary patency was 83% for saphenous vein and 67% for polytetrafluoroethylene (P =.065); the secondary patency was 83% for saphenous vein and 77% for polytetrafluoroethylene (P =.298). During a follow-up period of 2 years, we found no statistically significant difference in primary and secondary patency between saphenous vein and polytetrafluoroethylene. We found no predictive factor for occlusion of either bypass graft.
                The use of polytetrafluoroethylene above the knee is a reasonable alternative in femoropopliteal bypass grafting that is associated with acceptable short-term patency rates. 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. 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. To compare polytetrafluorethylene (PTFE) and polyester grafts (Dacron) for above knee femoropopliteal bypass.
                Multicenter randomised clinical trial.
                427 patients were randomised between 6mm Dacron (Uni-Graft, B. Braun Melsungen AG, 34212 Melsungen, Germany) and PTFE (Goretex, W. L. Gore & Ass. Inc., Newark DE 19711, USA) above-knee femoropopliteal bypass grafts within 13 centres in Denmark (n=261), Norway (n=113) & Finland (n=53) between 1993 and 1998. Fourteen (3%) patients were excluded, leaving 413 patients with 208 Dacron and 205 PTFE grafts for analysis. Age, gender, indication (claudication: 65%), run-off (2 or 3 vessels: 76%), diabetes (17%) and hypertension (31%) as well as cerebrovascular (9%) and cardiac (33%) risks were evenly distributed. Patients were followed postoperatively at 1, 12 and 24 months. Patency assessment was based on ankle-brachial pressures or imaging in case of doubt.
                The two-year primary patency rates for Dacron and PTFE were 70% and 57% (p=0.02), whereas the secondary patency rates were 76% and 65% (p=0.04), respectively. Primary patency at two years was significantly influenced by the number of patent crural vessels (two or three 67%, one 50%, p=0.01). Amputations at two years, major in 4% and minor in 3%, 30-days mortality and complications (wound infections: 3% and other wound complications: 13%) occurred equally frequent in both groups. At two years, patients treated for critical limb ischemia had a major amputation more often than patients operated on for intermittent claudication, 10 and 3 respectively (p=0.003), and had higher mortality rates, 20% and 8% respectively (p=0.001).
                This trial confirms that Dacron is at least as durable as PTFE for above-knee bypass procedures, and might even be superior. Dacron was largely abandoned for femoropopliteal bypass 30 years ago, because better patency rates were achieved with saphenous vein. Despite the range of potential prosthetics, polytetrafluoroethylne (PTFE) clearly predominates in current femoropopliteal practice. We compared heparin-bonded Dacron (HBD) with PTFE in a randomized multicenter clinical trial.
                Over 28 months, 209 patients (179 above-knee disease, 30 below-knee disease) were randomized to receive HBD (n = 106) or PTFE (n = 103) grafts. Aspirin, 300 mg/d, was started before surgery, and was continued if tolerated.
                At follow-up for a minimum of 5 years (mean, 76 months; range, 60-89 months), 37 patients (17.7%) had died with patent grafts and 121 (58%) grafts were occluded. Primary patency rate, measured with Kaplan-Meier survival analysis, was 46% (95% confidence interval [CI], 35%-57%) at year 5 for HBD, compared with 35% for PTFE (CI, 25%-45%; P < .055). Long-term patency was achieved in only 4 of 78 interventions performed in 55 thrombosed grafts. Secondary patency rate for HBD was 47% (CI, 36%-58%), and for PTFE was 36% (CI, 26%-46%). Risk factors for arterial disease did not significantly influence prosthetic patency. Major limb amputation was necessary in 9 patients with HBD grafts and 20 patients with PTFE grafts (P < .025). Two amputations in the HBD group and 8 amputations in the PTFE group were in patients undergoing bypass surgery to treat claudication only. Limb salvage rate was 86% (CI, 77%-95%) and 74% (CI, 64%-84%), respectively.
                Significantly better patency rates were achieved with HBD than with PTFE at 3 years (P < .044), but the difference was no longer statistically significant at 5 years (P < .055). The incidence of major limb amputation, however, was significantly greater (P < .025) in the PTFE group compared with the HBD group at both 3 and 5 years of follow-up. Despite many clinical studies, there is still uncertainty as to whether venous material is superior to prosthetic materials for femoropopliteal reconstruction proximal to the knee joint. A prospectively randomized clinical trial was designed to evaluate the effectiveness of reversed saphenous vein in comparison with that of collagen impregnated woven polyester prosthesis in above-knee arterial reconstruction.
                In a 3-year period, 103 above-knee femoropopliteal bypass graft operations were performed and followed in 85 patients (52 male, 33 female). The indication for operation was severe claudication in 74 cases, rest pain in 7 cases, and ulceration in 4 cases. For the bypass graft, a reversed saphenous vein was used in each of 51 cases, and a collagen impregnated woven polyester prosthesis was used in each of 52 cases. Preoperative risk factors were diabetes (24%), a history of myocardial infarction (23%), and current status with respect to smoking (74%). There was no hospital mortality; 5% of patients had minor postoperative complications.
                After 2 years of follow-up, the primary patency was 81% for saphenous vein and 67% for collagen impregnated woven polyester prosthesis (P=0.065); the secondary patency was 81% for saphenous vein and 77% for collagen impregnated woven polyester prosthesis (P=0.298). During this follow-up period of 2 years, we found no statistically significant difference in primary and secondary patency between saphenous vein and collagen impregnated woven polyester prosthesis. We found no predictive factor for the occlusion of either bypass graft.
                The use of collagen impregnated woven polyester prosthesis above the knee is a reasonable alternative in femoropopliteal bypass grafting that is associated with acceptable short-term patency rates. 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.