Abstract
We studied the healing characteristics and the patency of CORVITA® vascular graft. Thirteen grafts were implanted in abdominal aorta of mongrel dogs. The graft used was 6mm in diameter and 6cm in length. Three dogs died within 14 days and the remaining 10 dogs were followed from 3 to 21 months. The gross appearance of the graft revealed good healing at both anastomotic sites, and mild anastomotic stenosis at 3 and 6 months after implantation. In histological examinationthe intimal thickness of these regions was about 100μm. But fibrin clot and thrombus were found focally on the surface of the same grafts and the intimal thickness was more than 500μm there. In these grafts, the endothelial cell coverage was localized within several millimeters from the anastomotic site in electon microscopy. In one graft, a segmental stenosis was seen at the middle and distal portion of the graft at 7 months after implantation. There were no thrombus on the surface of the graft and the neointima was almost completed at 20 months after implantation. Seven grafts remained patent from 3 to 21 months (average 11.6 months) and the patency rate was 70%. In conclusion, severe anastomotic intimal hyperplasia was not seen in this study. But the intimal healing of CORVITA® graft is not better than we expected.
