Our objectives were to determine procedural success, clinical complications, and follow-up restenosis rates after rotational burr and transluminal extraction atherectomy of coronary artery and saphenous vein graft ostial stenoses. Balloon angioplasty of ostial lesions has been associated with low rates of success and high rates of clinical complications and restenosis compared to nonostial lesions. Atherectomy, due to its ability to excise (extraction atherectomy) or pulverize (rotational atherectomy) atheroma and the internal elastic lamina, may result in improved procedural outcome. We retrospectively studied 101 patients with ostial stenoses treated by rotational burr and transluminal extraction atherectomy over a 3-yr period. Quantitative angiography and clinical follow-up were reviewed to determine success, complication, and restenosis rates. Rotational burr (n = 29) and transluminal extraction (n = 72) atherectomy were associated with high procedural success (93% and 90%, respectively) and a low incidence of complications (6.9% and 4.2%, respectively). Post-atherectomy angiographic success was low (52% and 69%, respectively) and required adjunctive balloon angioplasty in 85% of patients overall. This lower success rate likely reflects device undersizing as the overall post-atherectomy artery to device ratio was near unity (0.95). The rates of angiographic ostial restenosis remain high (39.1% and 65.9%, respectively, P < 0.05). The high rate of restenosis after transluminal extraction atherectomy was due to the higher rate of restenosis in saphenous vein grafts (80%) compared to TEC treated coronary arteries (59%). When only coronary artery lesions were compared, there was no significant difference between atherectomy device groups with respect to restenosis rates or late loss.(ABSTRACT TRUNCATED AT 250 WORDS)