IntroductionAutologous vein is recommended for infrainguinal bypass due to improved freedom from occlusion compared to prosthetic graft. In patients without adequate vein, vein adjunct at the distal anastomosis has been suggested to improve patency in small studies. This study aimed to determine if performance of a distal vein adjunct was associated with improved freedom from occlusion in below knee popliteal and tibial bypasses compared to prosthetic bypass alone. MethodsA retrospective review of the Vascular Quality Initiative Infrainguinal Bypass database was conducted. Patients undergoing prosthetic-only and prosthetic with vein adjunct were compared. Inclusion criteria included age >18 years, and bypass to below knee popliteal or tibial vessels. Exclusion criteria included autologous vein conduits and prior interventions. Groups were further divided into below knee popliteal and tibial subgroups. ResultsA cohort of 3,939 patients underwent bypass to the below knee popliteal artery, with 287 (7.3%) receiving vein adjunct. More patients were male (68.8 vs 57.8%, p<.001) and had higher rates of CHF (21.1 vs 16.0%, p=.040) within the below knee popliteal group. Two-year bypass occlusion was decreased in patients receiving vein adjuncts (11.6 vs 17.1%, p=.004). A cohort of 2,378 patients underwent tibial bypass, with 473 (19.9%) receiving vein adjunct. Within the tibial group, patients were similar in age, BMI, race, comorbidities, and indications. Bypass occlusion (24.8 vs. 17.6%, p=.005) and amputation (20.5 vs. 15.9%, p=.048) rates at two years were worse for patients who did not receive a distal vein adjuncts to tibial arteries. ConclusionDistal vein adjuncts are associated with improved freedom from occlusion, amputation, MALEs, and overall survival when compared to bypasses performed with prosthetic graft alone for tibial bypasses within the VQI. Vein adjunct was not associated with improved freedom from occlusion in below knee popliteal bypasses. Consideration should be given to utilization of a distal vein adjunct to improve prosthetic bypass longevity and limb salvage for patients requiring tibial bypasses.