Coronary atherectomy and coronary stenting effectively reduce the severity of coronary artery stenoses, but direct comparisons of these interventions with conventional balloon angioplasty have not been performed. To compare the immediate efficacy of these 3 interventions, the angiographic morphology and the severity of the residual coronary stenosis were quantitatively evaluated in 18 patients undergoing coronary atherectomy and in 21 patients treated by endoluminal coronary stenting. Each of these groups of patients was compared with a matched group of coronary angioplasty patients selected from a large, computerized data-base. The variables matched included patient age and sex, lesions site and severity, and lesion complexity. Both coronary atherectomy and coronary stenting more effectively reduced the severity of the coronary stenosis when compared with balloon angioplasty. The luminal diameter stenosis was reduced from 69 +/- 10 to 22 +/- 20% in the atherectomy group compared with a reduction from 74 +/- 11 to 44 +/- 14% in the matched coronary angioplasty population (p = 0.008). Similarly, the luminal diameter stenosis was reduced from 77 +/- 11 to 26 +/- 12% in the stented group compared with a reduction from 81 +/- 10 to 42 +/- 14% in the matched coronary angioplasty group (p = 0.014). In addition, moderate or severe coronary dissections were noted more frequently in the coronary angioplasty groups than in their respective atherectomy and stent groups (0 vs 33%, p = 0.008, and 5 vs 19%, p = 0.15, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)