The value of adjunctive vein patches to improve the outcome of femorodistal polytetrafluoroethylene bypass grafts

Purpose: A non-randomised comparative study was carried out to determine whether an interposition vein patch improves the long-term outcome of infrapopliteal and distal PTFE bypass grafts. Patients and methods: A prospective study (1992-1999) was carried out between 2 groups of patients. The first group comprised 86 patients undergoing the same number of femoropopliteal or infrapopliteal bypass procedures between March 1992 and February 1999 at our institution. PTFE with modified interposition vein patch was used as bypass graft. The second group comprised 191 patients who received 216 autogenous vein bypass grafts in the same period. The third group consisted of 94 patients from a retrospective study between 1985-1992, in whom PTFE bypass procedures without interposition vein patches had been performed. The indication for surgery was critical lower limb ischemia in all groups. Primary, secondary and limb salvage rates were calculated using the life-table method. The life tables were compared with the log-rank test. Results: Five-year primary, secondary and limb salvage rates for PTFE with interposition vein patches were 53.4%, 60.7% and 68% for below- knee popliteal, and 29.5%, 35.5% and 41% for infrapopliteal bypass grafts, respectively. Five-year primary, secondary and limb salvage rates for autogenous vein grafts were 78.9%, 82.3% and 84.2% for below-knee popliteal, and 51%, 54.7% and 75% for infrapopliteal bypass grafts, respectively. Five-year primary, secondary and limb salvage rates for PTFE grafts without interposition vein patches were 29.7%, 37.8% and 43.6% for below-knee popliteal, and 6.9%, 9.2% and 14.7% for infrapopliteal bypass grafts, respectively. Statistical analysis showed a significant difference in primary, secondary and limb salvage rates between the groups. Conclusion: The results of our study indicate that autogenous vein still remains the graft of choice for below-knee and infrapopliteal bypass reconstruction. Their longterm patency and limb salvage rates were significantly better compared with PTFE grafts, with or without interposition vein patches. When adequate autogenous vein is not available, the interposition of a vein patch considerably improves the long-term outcome of PTFE bypass grafts.