Endothelial seeding of polytetrafluoroethylene popliteal bypasses. A preliminary report.

At St. Vincent Hospital, Indianapolis, 17 patients have undergone femoropopliteal bypass operations with polytetrafluoroethylene (PTFE) grafts that were seeded with enzymatically harvested, autogenous endothelium. Three patients received seeded grafts because satisfactory veins were not available. Twenty-eight patients alternately received seeded or unseeded, externally supported e-PTFE grafts. Graft patency was evaluated by clinical criteria and changes in the Doppler ankle-brachial systolic pressure ratios at 2 and 30 days postoperatively and at 3-month intervals thereafter. Occlusions were defined arteriographically if the clinical situation or the Doppler findings deteriorated. Smoking histories were taken, and carboxyhemoglobin (COHgb) levels were sampled 1 month postoperatively. Cumulative patency after 3 months was 93.3% +/- 6.5% for seeded and 84.0% +/- 10.4% for unseeded grafts. After 1 year it was 81.6% +/- 12.3% for seeded grafts and 30.8% +/- 18.7% for unseeded grafts (p = 0.02). Thus far all but one of the occlusions have occurred in patients with a history of smoking or with a COHgb level greater than 1.5%, whereas all of the seeded grafts in nonsmokers with COHgb levels less than or equal to 1.5% are patent. We conclude that endothelial seeding of PTFE femoropopliteal grafts is feasible. During this preliminary study period, a small number of patients had favorable patency rates with seeded as compared with unseeded grafts, especially among smokers. A multiple-institution study will be needed to establish the role of endothelial cell seeding in the treatment of vascular occlusions of the femoral and popliteal arteries.