Comparative evaluation of externally supported Dacron and polytetrafluoroethylene prosthetic bypasses for femorofemoral and axillofemoral arterial reconstructions

Purpose: Currently, the choice of a vascular prosthesis for an extra-anatom ic arterial bypass graft is left to the surgeon's preference because well-d esigned comparative evaluations have not been performed. The Department of Veterans Affairs Cooperative Study 141 was organized to identify whether th ere is improved patency with different prosthetic grafts for patients with femorofemoral or axillofemoral bypass grafts. Methods: Between June 1983 and June 1988, patients at 20 Veterans Affairs M edical Centers who had aortoiliac occlusive disease but were not considered suitable candidates for aortic bypass surgery were randomized to receive e ither an externally supported polytetrafluoroethylene or Dacron bypass graf t for an extra anatomic bypass. Doppler-derived ankle brachial indices (ABI s) were determined before the operation and serially after the operation. P atients were seen in follow-up every 3 months for the first year and every 6 months thereafter. All patients were instructed to take 650 mg of aspirin each day for the duration of the study. A bypass graft was considered to b e patent if the Doppler-derived postoperative ABI remained significantly im proved (0.15 units above the preoperative value), and additional clinical i nformation (such as subsequent ABIs, angiograms, or operations) did not con tradict these observations. Results: Three hundred forty patients with femorofemoral bypass grafts and 79 patients with axillofemoral or axillofemorofemoral bypass grafts were ra ndomized. The indication for the bypass operation was limb salvage in 72% o f the patients. The assisted primary patency rate for a Dacron bypass graft ing was 79% at 1 year, 63% at 3 years, and 50% at 5 years; for polytetraflu oroethylene bypass grafting, the patency was 77% at 1 year, 62% at 3 years, and 47% at 5 years. Conclusion: The overall results of this prospective randomized study sugges t that the current choices of prosthetic bypass grafting have similar long- term patency in patients who undergo femorofemoral or axillofemoral vascula r reconstruction.