Elastic and thrombogenic properties for different vascular grafts and its influence on graft patency

In a sheep model elastic and thrombogenic properties for various vascular graft materials were studied using peroperative compliance measurements and Indium-111-oxine labeled platelets in vivo. It was found that the least thrombogenic arterial vascular substitute was the autologous vein while a significantly higher thrombogenicity was recorded for the polytetrafluoroethylene (PTFE) graft and the Chinese pure silk graft. The two latter grafts did not differ significantly in thrombogenicity except for that the silk graft revealed a significantly higher peak value for deposited platelets onto its surface than the PTFE graft. Compliance measurements at graft implantation revealed that both the silk and the vein grafts were more elastic than the PTFE graft. The two grafts did not differ in elasticity from each other significantly. Elasticity for all grafts increased during the first 10 weeks after implantation. There was a good correlation between elastic properties and graft patency for all tested graft materials. However, the silk graft with favourable elastic characteristics was found to have less favourable thrombogenic properties and is therefore in its present form not the ideal graft for small caliber artery reconstructions.