ENDOTHELIAL SEEDING OF POLYTETRAFLUOROETHYLENE FEMORAL POPLITEAL BYPASSES - THE FAILURE OF LOW-DENSITY SEEDING TO IMPROVE PATENCY

Purpose: We compared 66 seeded polytetrafluoroethylene and 53 autologous vein grafts to determine whether endothelial seeding could improve the patency of polytetrafluoroethylene femoral popliteal bypass grafts and to determine whether endothelial seeding could be performed consistently in multiple institutions. Methods: Nine surgeons at four hospitals randomized patients to receive either a seeded polytetrafluoroethylene or a vein graft, but if no satisfactory vein (It = 26) existed, an ''obligatory'' seeded polytetrafluoroethylene graft was used. Results: Scanning electron microscopy confirmed satisfactory initial attachment of endothelium on the discarded ends of the grafts. Patency was compared with the use of log rank analysis and revealed better patency in vein grafts at 30 months (vein 91.6% +/- 4.1%; seeded polytetrafluoroethylene = 37.8% +/- 9.4%; p = 0.006). Failed grafts revealed anastomotic hyperplasia. Conclusions: (1) Vein graft patency was better than seeded polytetrafluoroethylene grafts; (2) seeding did not improve patency in below-the-knee bypasses as suggested by pilot studies; (3) the failure of seeded grafts was associated with anastomotic hyperplasia but not with the failure of initial endothelial attachment; and (4) each institution reported similar results.