Fluoropolymer coated dacron or polytetrafluoroethylene for femoropopliteal bypass grafting: a multicentre trial

Background: This trial was designed to compare graft patency between expanded polytetrafluoroethylene (PTFE) and fluoropolymer coated Dacron for femoropopliteal bypass in patients in whom saphenous vein was unavailable. Methods: A multicentre prospective trial randomized 129 patients (74 men, 55 women) who underwent femoropopliteal bypass using either a PTFE or fluoropolymer coated Dacron graft. The indication for operation was disabling claudication in 68 (52.7%) and critical limb ischaemia in 61 (47.3%) patients. Distal anastomosis was above the knee in 76 (58.9%) and below the knee in 53 (41.1%) patients. Results: Primary patency at 6, 12 and 24 months was 71%, 56% and 47% for PTFE and 50%, 36% and 36% for fluoropolymer coated Dacron (P = 0.002), respectively. Secondary patency at 6, 12 and 24 months was 77%, 60% and 48% for PTFE and 66%, 49% and 46% for fluoropolymer coated Dacron (P = 0.13), respectively. The superior primary patency of PTFE over fluoropolymer coated Dacron was most evident in patients with poor prognostic indicators for graft survival: critical limb ischaemia (P = 0.001); below-knee anastomosis (P = 0.01); and smaller (6 mm) diameter grafts (P = 0.002). Graft thrombosis developed in the first month in 22 of 61 (36%) patients receiving fluoropolymer coated grafts compared to six of 68 (8.8%) patients receiving PTFE, which accounts for the difference in primary patency. Successful thrombectomy in 10 of the 22 fluoropolymer coated grafts resulted in similar secondary patency. Conclusion: Polytetrafluoroethylene has superior primary patency and similar secondary patency to fluoropolymer coated Dacron. These results support the preferential use of PTFE in patients with critical limb ischaemia, especially when a below-knee distal anastomosis and smaller diameter graft is required.