Abstract
Surface-modified ePTFE grafts (2mm internal diameter and 30μm fibril length) produced by immobilization of fibronectin (FN) and by intermediary methacrylic acid (MA) grafting were implanted into the carotid arteries of New Zealand White rabbits to study early thrombogenicity, patency, and graft healing. In MA- or MA/FN-immobilized grafts, there were observed a smooth and thin fibrin thrombus layer on the luminal surface at 1 day, equivalent patency rates up to 12 weeks, and 3-6 times increase in endothelial coverage at 4 weeks, as compared with those observed in untreated grafts. In MA/FN-immobilized grafts, the improved endothelialization was seen at 12 weeks but not MA-immobilized grafts and thick pseudointima was formed compared with untreated and MA-immobilized grafts. These results suggest that the improved endothelialization of FN-immobilized ePTFE grafts is dependent on the appropriate pseudointima formation in addition to the formation of smooth thrombus layer on the luminal surface.
