Summary

Male Wistar rats were used to evaluate micro-venous prosthetic grafting techniques and microvenous prostheses in the femoral vein. With the end-to-end technique to implant microvenous prostheses, there was extensive exposure of vessel wall collagen especially at the suture sites. Thrombus formation then led to complete occlusion in all but one of the 32 prostheses 60 min after implantation. However, with the sleeve anastomotic technique there was only minimal exposure of collagen and minimal thrombus accumulation. Fifty-nine of the 64 microvenous prostheses implanted with the sleeve technique were patent after 1 day, 1,3,6, and 12 weeks (patency rate 921170). All patent micro-venous prostheses were completely covered by an endothelial layer after 3 weeks. It was concluded that the rat is an appropriate experimental laboratory animal for evaluating new grafting techniques with microvenous prostheses and that the sleeve anastomotic technique gives the highest patency rates with microvenous prostheses