A meta-analysis to compare Dacron versus polytetrafluroethylene grafts for above-knee femoropopliteal artery bypass.
Surgical revascularization for lower limb ischemia remains an important component for optimization of quality of life and symptoms in patients with peripheral arterial disease. In the absence of a vein graft, prosthetic alternatives are considered. The objective of this meta-analysis was to establish which prosthetic graft, Dacron or polytetrafluroethylene (PTFE), has the better long-term patency in patients undergoing an above-knee femoropopliteal arterial bypass.
This meta-analysis was performed by use of Cochrane and Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. An electronic search of all relevant databases was performed from 1990 to 2013 with the Medical Subject Headings "Dacron," "polytetrafluroethylene," "PTFE," "above knee," "femoropopliteal," and "bypass" combined with the Boolean operator "AND." The inclusion criteria were randomized controlled trials, use of Dacron vs PTFE prosthetic conduits, and completion of an above-knee femoropopliteal arterial bypass involving adult patients older than 18 years presenting with disabling claudication, rest pain or tissue loss, occlusion of the superficial femoral artery, and reconstitution of the above-knee popliteal artery. Whenever studies included above- and below-knee data, only the above-knee arterial bypass data were extracted and analyzed. Graft patency rates were calculated with RevMan 5.1 software provided by the Cochrane Collaboration.
Ninety-one publications were reviewed. After exclusion of duplicate, nonrandomized, and alternative bypass surgery studies, eight randomized controlled trials were identified and included in the meta-analysis. Two of the included trials represented follow-up evaluation of two previous studies, and for the purpose of this analysis, the initial and follow-up studies were subsequently evaluated as one trial. In this meta-analysis, 1192 patients were assessed, including 601 Dacron and 591 PTFE above-knee lower limb arterial bypasses. Primary patency was calculated from all included studies. However, only four studies provided data to evaluate secondary patency. Mean age reported was 66 years. Although all studies described cardiovascular comorbidities and risk factors including myocardial ischemia, diabetes, hypertension, and smoking, exact patient numbers were not consistently provided. Included studies evaluated grafts from 5 to 8 mm. Although primary and secondary patency rates at 12 months were not significantly different (relative risk [RR], 0.78; P = .08, and RR, 0.84; P = .52), 24-, 36-, and 60-month primary patency rates were significantly better with Dacron compared with PTFE grafts (RR, 0.79; P = .003; RR, 0.80; P = .03; RR, 0.85; P = .02). Statistical analysis also supported higher secondary patency rates for Dacron at 24 months (RR, 0.75; P = .02) and 60 months (RR, 0.76-0.77; P = .03-.27). Although primary patency was similar between grafts (28% vs 28%; P = .12), secondary patencies were better with Dacron at 10 years (49% vs 35%; P = .01). Antiplatelet and anticoagulation protocols varied between the trials. There was no difference in amputation, overall morbidity, or mortality rates between the two surgical graft populations.
Current evidence suggests that Dacron prosthetic grafts are superior to PTFE grafts in above-knee femoropopliteal arterial bypass procedures. Further randomized trials targeting standardization of confounding variables, particularly graft size and best medical therapy, are warranted.
Rychlik IJ
，Davey P
，Murphy J
，O'Donnell ME
... -
《-》
Comparison of graft patency, limb salvage, and antithrombotic therapy between prosthetic and autogenous below-knee bypass for critical limb ischemia.
The autogenous vein is the preferred conduit in below-knee vascular reconstructions. However, many argue that prosthetic grafts can perform well in crural bypass with adjunctive antithrombotic therapy. We therefore compared outcomes of below-knee prosthetic versus autologous vein bypass grafts for critical limb ischemia and the use of adjunctive antithrombotic therapy in both settings.
Utilizing the registry of the Vascular Study Group of New England (2003-2009), we studied 1227 patients who underwent below-knee bypass for critical limb ischemia, 223 of whom received a prosthetic graft to the below-knee popliteal artery (70%) or more distal target (30%). We used propensity matching to identify a patient cohort receiving single-segment saphenous vein yet had remained similar to the prosthetic cohort in terms of characteristics, graft origin/target, and antithrombotic regimen. Main outcome measures were graft patency and major limb amputation within 1 year. Secondary outcomes were bleeding complications (reoperation or transfusion) and mortality. We performed comparisons by conduit type and by antithrombotic therapy.
Patients receiving prosthetic conduit were more likely to be treated with warfarin than those with greater saphenous vein (57% vs. 24%, P<0.001). After propensity score matching, we found no significant difference in primary graft patency (72% vs. 73%, P=0.81) or major amputation rates (17% vs. 13%, P=0.31) between prosthetic and single-segment saphenous vein grafts. In a subanalysis of grafts to tibial versus popliteal targets, we noted equivalent primary patency and amputation rates between prosthetic and venous conduits. Whereas overall 1-year prosthetic graft patency rates varied from 51% (aspirin+clopidogrel) to 78% (aspirin+warfarin), no significant differences were seen in primary patency or major amputation rates by antithrombotic therapy (P=0.32 and 0.17, respectively). Further, the incidence of bleeding complications and 1-year mortality did not differ by conduit type or antithrombotic regimen in the propensity-matched analysis.
Although limited in size, our study demonstrates that, with appropriate patient selection and antithrombotic therapy, 1-year outcomes for below-knee prosthetic bypass grafting can be comparable to those for greater saphenous vein conduit.
Suckow BD
，Kraiss LW
，Stone DH
，Schanzer A
，Bertges DJ
，Baril DT
，Cronenwett JL
，Goodney PP
，Vascular Study Group of New England
... -
《-》
The effect of graft configuration on 30-day failure of infrapopliteal bypasses.
Despite advances in endovascular techniques, infrapopliteal bypasses are still required for limb salvage. Short-term graft patency is an important outcome parameter reflecting technical considerations and acute graft thrombosis. Both are important prerequisites for long-term patency. In this analysis, we compared the 30-day patency of all conduit configurations for infrapopliteal bypasses.
All primary infrapopliteal bypasses from the American College of Surgeons-National Surgical Quality Improvement Program database between 2005 and 2010 were divided into six groups: (1) great saphenous vein (GSV); (2) prosthetic conduit (prosthetic); (3) prosthetic conduit with a distal anastomotic venous adjunct (ADJ), such as a cuff or patch (prosthetic + ADJ); (4) composite graft of prosthetic and a vein segment (composite); (5) spliced autogenous vein (spliced vein); and (6) arm vein. Thirty-day graft failure, patient demographics, and operative details were compared among groups. A multivariate model was used for statistical analysis.
A total of 5375 infrapopliteal bypasses were analyzed by conduit: GSV, 3983 (75%); prosthetic, 898 (17%); spliced vein, 160 (3%); prosthetic + ADJ, 112 (2%); arm vein, 93 (2%); and composite, 91 (2%). The difference among groups in demographics and comorbidities was not statistically significant. Perioperative mortality rates were similar among different conduits. After adjusting for sex, age, weight, race, and previous cardiac surgery, the bypass conduit had a significant independent association with 30-day graft patency (P = .006). The GSV failure rate was 7.5%. Composite had a significantly higher 30-day failure rate (15.4%, P = .006). There was no significant difference in 30-day failure rate of spliced vein (5.6%, P = .37) or arm vein (4.3%, P = .24) conduits compared with GSV. Prosthetic had significantly higher 30-day failure rate than GSV (10.5%, P = .004). The addition of adjuvant venous tissue at the distal anastomosis of prosthetic bypasses did not significantly improve their 30-day patency (failure rate of 9.8% for prosthetic + ADJ and 10.5% for prosthetic). There was no significant difference in graft patency between alternative venous conduits (arm vein/spliced vein) and prosthetic + ADJ.
Venous conduits (GSV, spliced vein, arm vein) deliver the best 30-day patency for infrapopliteal bypasses, and GSV remains the most commonly used graft. Prosthetic grafts had a higher 30-day failure rate. Composite grafts should be abandoned because their early patency is not better than pure prosthetic conduits. The addition of a distal venous adjunct did not seem to improve acute prosthetic graft patency, which may reflect lack of effect on thrombogenicity rather than the myointimal hyperplastic response that effects long-term failure of infrapopliteal bypass.
Nguyen BN
，Neville RF
，Abugideiri M
，Amdur R
，Sidawy AN
... -
《-》
ResearchGate
(全网免费下载)
钛学术
(全网免费下载)
