Aneurysm Formation and Perforation in Glutaraldehyde-Tanned Umbilical Vein Grafts

Abstract

Dilatation and perforation of the prosthetic wall represent major problems limiting long-term function of biologic arterial substitutes. One case of multiple aneurysm formation and one of graft wall perforation, occurring nine and three years, respectively, after human umbilical vein (HUV) femoropopliteal reconstructions, are reported. Both grafts were well functioning. At microscopic examination, the aneurysmal HUV wall showed no degenerative changes, while appearing thinner with respect to the undilated zones (about one third). The HUV flow surface remained thromboresistant, except for the dilated areas. Partial endothelialization of the inner graft surface was documented. In conclusion, the risk of HUV graft dilatation and perforation increases when function is maintained for periods longer than three years from implantation. However, the umbilical vein retains over time its thromboresistant properties.