The periprocedural events and myocardial function during nonocclusive coronary atherectomy by Rotablator or transluminal extraction catheter (TEC) may differ from events during balloon angioplasty. This may have important clinical consequences and needs to be defined further. Therefore, 17 patients undergoing Rotablator and 18 undergoing TEC atherectomy were assessed by clinical, hemodynamic and electrocardiographic monitoring and simultaneous transesophageal echocardiography. The findings were compared with similar parameters during subsequent balloon angioplasty performed in 16 of 17 patients undergoing Rotablator and 14 of 18 undergoing TEC atherectomy. Chest pain occurred more frequently during balloon inflation than during either atherectomy (p less than 0.02), whereas ST-segment and T-wave electrocardiographic changes were equally frequent. Transient second- or third-degree atrioventricular block occurred in 6 patients during Rotablator but in none during TEC atherectomy or balloon inflation (p less than 0.01 for each). Hemodynamic parameters and global left ventricular function remained unchanged during atherectomy. Regional myocardial function in the distribution of the target coronary artery, assessed by a wall motion score, was not affected during Rotablator, but deteriorated slightly during TEC atherectomy and more significantly during balloon inflation (score from 0.3 +/- 0.5 to 1.0 +/- 0.7 during TEC and 2.0 +/- 0.6 during balloon inflation, p less than 0.005 for both). Thus, chest pain is infrequent, whereas hemodynamics and global left ventricular function are preserved during Rotablator and TEC atherectomy. Transient atrioventricular block during Rotablator and regional myocardial dysfunction during TEC atherectomy may occur without significant consequences. These data suggest that these techniques may be preferable to balloon angioplasty for preserving intraprocedural left ventricular function.