Are femoro-infrapopliteal bypasses worthwhile for limb salvage?

Objective: This study was performed in order to determine if: 1-- femoral bypasses ending below the popliteal artery are justified in aged patients or in patients with poor general conditions, 2-- if the use of prosthetic material is justified when no vein is available, 3-- if reintervention is beneficial in case of bypass occlusion.

Experimental Design: Retrospective study of 162 infrapopliteal bypasses followed during 1 to 12 years (mean: 1.5).

Setting: Vascular Surgery Department of the University Hospital Henri Mondor based in a suburb of Paris, France.

Patients: All patients who underwent a femoral bypass ending below the popliteal artery for limb salvage from January 1984 to December 1995.

Intervention: These bypasses were performed with a vein in 131 cases and with a PTFE graft (with or without distal cuff) in 31 cases.

Measures: All patients were followed with clinical evaluation and duplex scan. Primary and secondary patency, limb salvage and patient survival were studied. The survival rates at 1 and 5 years were 87+/-3.8% and 66+/-9.6% respectively. Preoperative mortality was 7.4%. Renal insufficiency requiring dialysis, not age over 80, was associated with high perioperative mortality.

Results: The primary patency rates of the total series at 1 and 5 years were 55 and 35% respectively for the total series. For venous bypasses, it was 58 and 37% while for prosthetic bypasses, it was 49 and 15%. The secondary patency rates at 1 and 5 years were 67 and 46% for the total series. For venous bypasses, it was 70 and 49% and for prosthetic bypasses, it was 53 and 21%. Limb salvage rates at 1 and 5 years were 65 and 61% for the total series, 73 and 65% for venous bypasses and 48 and 41% for prosthetic bypasses.

Conclusion: 1-- Femorotibial or peroneal bypasses are worthwhile for limb salvage even in aged patients but renal insufficiency requiring dialysis may justify primary amputation. 2-- If no vein can be used, prosthetic or composite bypasses should be performed because they are associated with a 41% limb salvage rate at 5 years. 3-- If thrombosis occurs, the increase of patency after re-operation is 12% in case of venous bypass and 6% in case of prosthetic bypass.