The failure of balloon angioplasty to provide a durable result has led to the development of other methods of catheter-associated interventional therapy. In this study, 112 patients with superficial femoral artery stenosis or occlusion were treated with percutaneous atherectomy. Patients were considered to have a simple lesion if the occluded or stenotic arterial segment was less than 5 cm, and a complex lesion if the length of the occluded segment was greater than 5 cm. All atherectomies were performed in the superficial femoral and popliteal arteries; urokinase thrombolysis was used in conjunction with atherectomy in 16 patients. Atherectomy was considered successful if there was less than 20% residual stenosis determined by arteriography. Initial atherectomy results (30 day patency) were 100% successful in the group with a simple lesion and 93% successful in the group with a complex lesion. At a mean follow-up period of 12 months (range 5 to 24), there was a continued patency rate of 93% and 86%, respectively, in the simple and complex groups. In the patients who had restenosis, all pathologic specimens obtained during the second procedure demonstrated myointimal hyperplasia and organized thrombus. Eight major complications (7.1%) occurred, including one fatal myocardial infarction. The complication rate was 3.5% in the simple group and 8.3% in the complex group. With the exception of the myocardial infarction, all complications were associated with catheter entry site hematomas. Femoropopliteal atherectomy has a high rate of success and low morbidity and mortality for both simple and complex lesions and is a viable and competitive alternative therapy for patients with severe peripheral vascular disease.(ABSTRACT TRUNCATED AT 250 WORDS)