Randomized Study of Noninferiority Comparing Prosthetic and Autologous Vein Above-Knee Femoropopliteal Bypasses

Abstract

Background: The main aim of this study was to compare the 5 years rates of secondary patency of above-knee femoropopliteal revascularizations with autologous veins or prosthetic grafts. The secondary objectives were to compare the rates of primary patency, limb salvage, morbidity, and mortality between the 2 groups.

Methods: This was a single-blind randomized study of noninferiority (ratio 1:1), carried out in 11 centers of vascular surgery with 2 parallel groups between July 2002 and November 2005. Follow-up finished in May 2011. The monitoring protocol included a clinical examination and an ultrasound control at 1 month, 3 and 6 months, then annually.

Results: One hundred patients were included and randomized in the study, 52 in the prosthetic group and 48 in the autologous vein group. Four patients randomized in the vein group received a prosthetic graft. No patient was excluded from the analysis. In the in intent-to-treat analysis, the 5 years secondary patency was 84.6% in the prosthetic group (IC 95%, 71.9-93.1) and 70.8% in the autologous vein group (IC 95%: 55.9-83.1), and the difference in secondary patency between the prosthetic and the autologous vein groups was 13.8% (IC 95%, -4.4 to 32.0). In the under treatment analysis, the 5 years secondary patency was 96.2% among patients receiving a prosthesis (IC 95%, 80.4-99.9) and 90.5% among patients receiving an autologous vein (IC 95%, 66.9-98.9), and the difference in the rate of patency between prostheses and veins was 5.7% (IC 95%, -13.2 to 24.6). Although there was no significant difference at 5 years, the death rate and the rate of amputation were higher in the prosthetic group.

Conclusions: Although it is impossible to conclude definitely to the noninferiority of prosthetic bypass compared with venous bypass because of the insufficient number of inclusions, this randomized study nevertheless showed at 5 years the satisfactory results obtained with prostheses compared with autologous vein for above-knee femoropopliteal bypasses.