Polytetrafluoroethylene graft aneurysms: a report of five aneurysms.

True aneurysms have developed in nonreinforced, expanded polytetrafluoroethylene (PTFE). We report our experience in arterial reconstructions with PTFE in the legs of patients having symptomatic occlusive disease. Fifty-four femoropopliteal or femorotibial bypass operations were performed in 51 patients between January 1975 and December 1976. An unsuitable saphenous vein for a vascular conduit was found in 14 patients, and reconstruction was done with PTFE (IMPRA-graft). Two of the 14 PTFE grafts were composite and used a segment of saphenous vein. Aneurysmal dilation developed in five PTFE grafts (36%) in four patients three to 36 months following placement. Nonreinforced PTFE conduits as manufactured during 1975 and 1976 are unsatisfactory for use as limb arterial bypass grafts because of the high incidence of aneurysmal change. Those that are implanted must be followed up indefinitely because of late aneurysmal formation and rupture. Newer PTFE graft modifications should be used with caution.