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

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.