Relationship Between Fibril Length and Tissue Ingrowth in the Healing of Expanded Polytetrafluoroethylene Grafts

Abstract

To determine whether fibril length is correlated with graft healing as well as cellular and capillary ingrowth in a canine carotid implantation model. Expanded polytetrafluoroethylene (ePTFE) vascular grafts with three different fibril lengths (30, 60, and 90 microm) were implanted into the carotid artery in dogs. They were retrieved 4 weeks later, and subjected to histomorphometric analysis. Endothelial healing was best in the 60-microm grafts. Not only cellular ingrowth but also capillary ingrowth was most evident in the 60-microm grafts, followed by the 90-microm grafts and then the 30-microm grafts. Better endothelial healing of ePTFE vascular grafts is correlated with more cellular and capillary ingrowth, but more cellular and capillary ingrowth is not correlated with longer fibril length or higher air porosity.