• A previous report from this group indicated a very poor long-term patency rate (19%) for occluded femoro-distal vein grafts that require initial thrombectomy prior to patch angioplasty for documented stenosis. Patients with vein grafts were therefore followed up by Doppler pressure determinations of the ankle/brachial index (ABI) postoperatively at three weeks, six weeks, and every four months thereafter for two years in an effort to identify vein-graft failure prior to actual thrombosis. During the past six years we performed 322 vein grafts of which 29 grafts were identified by diminished Doppler ABI and were found to have stenotic segments on subsequent arteriography. Twenty-two of these patients (group 1) underwent reconstruction with patch angioplasty resulting in a five-year cumulative patency rate of 82%. The remaining seven patients (group 2) underwent percutaneous transluminal angioplasty of their stenotic segments yielding a significantly lower five-year patency rate of 43%. These two groups were compared with a third group of 25 patients with thrombosed grafts mandating initial thrombectomy prior to patch angioplasty. The thrombectomized group 3 patients demonstrated a significantly lower five-year cumulative patency rate of 28%. These data suggest that patients with femoro-distal bypass vein grafts be followed up at frequent intervals early in their postoperative course with determinations of Doppler ABI measurements. Any significant reduction in Doppler ABI compared with the highest postoperative Doppler determination should be aggressively evaluated with digital-subtraction or routine angiography in an effort to locate a stenotic lesion prior to graft thrombosis. Patients found to have such a graft stenosis are then ultimately treated with patch angioplasty in anticipation of satisfactory long-term patency rates. (Arch Surg 1986;121:758-759)