Veno-venous allografts: patency, subendothelial proliferation, and the role of platelet-active agents.

Patency and histology of 81 vein allografts and 10 autografts in the canine femoral venous system were compared and the effect of platelet active agents in altering patency rates and subendothelial proliferation in allografts was examined. It was found that allografts thrombose at a predictable interval after operation (18 +/- 7 days) and have significantly worse survival than autografts (P less than 0.001). Platelet-active agents did not alter allograft patency rate of the incidence of subendothelial proliferation in this model.