DO DISTAL ARTERIOVENOUS-FISTULAS IMPROVE PATENCY RATES OF PROSTHETIC INFRAPOPLITEAL ARTERIAL BYPASSES

We retrospectively analyzed if distal anastomotic adjunctive arteriove nous fistulae (AVF) improved patency rates of prosthetic bypasses to i nfrapopliteal arteries. Between July 1, 1991 and June 30, 1996, we per formed 43 polytetrafluoroethylene (PTFE) bypasses to infrapopliteal (1 9 peroneal, 13 anterior tibial, 11 posterior tibial) arteries. All byp asses were performed for limb salvage when autologous vein was not ava ilable for a conduit. Adjunctive AVFs were performed in 21 bypasses (P TFE-AVF) and 22 bypasses did not have a fistula (PTFE-ONLY). Patients were allocated to the PTFE-AVF or PTFE-ONLY groups at the discretion o f the surgeons, with adjunctive AVFs being performed for small arterie s with poor run-off. There were no significant differences in age, sex , site of the proximal anastomosis, or indication for surgery (p > 0.0 5). There were statistically significant differences in the site of di stal anastomosis and quality of arterial run-off based on the Society for Vascular Surgery Ad Hoc Committee on Reporting Standards criteria (p < 0.05). All patients were placed on heparin 500 units/hour postope ratively, maintained on life-long Coumadin and followed every 3 months with duplex ultrasonography to assess graft patency. Aggressive inter vention was carried out for failing grafts suspected by duplex scannin g. The hospital mortality rate was 2.3% (1/43; 1 PTFE-AVF). Two-year p rimary patency rates were significantly better for PTFE-AVF grafts tha n for PTFE-ONLY grafts (23% versus 5%) (p = 0.04). Although statistica l significance was not reached, there was a suggestion of higher assis ted primary (34% versus 1 5%) (p > 0.05) and secondary (61% versus 48% ) (p > 0.05) patency rates in the PTFE-AVF group versus the PTFE-ONLY group, although limb salvage rates were similar (74% versus 71%) (p > 0.05). Two AVFs required ligation because of steal resulting in dimini shed distal perfusion. These results support the use of adjunctive dis tal AVFs to improve overall two-year patency rates of prosthetic infra popliteal arterial bypasses.