Patency failures in microvascular prosthetic grafts

Thirty knitted prosthetic grafts (calibre 2 mm, length 10 mm) of three different types were implanted into abdominal aorta of Wistar rats. The types were as follows: Type 1 (n=10), multifilamentous Dacron coated with polyurethane; Type 2 (n=10), monofilamentous Dacron coated with polyurethane; type 3 (n=10) multifilamentous Dacron coated with polylactide. The patency rates of the grafts were 10% after 1 month, and 0% after 2 months. The prostheses proved unworkable owing to high incidence of acute thrombosis, lack of endothelium formation, chondrification, and formation of collateral blood sinuses.