Restenosis after successful percutaneous coronary angioplasty (PTCA) is a major problem because it occurs in 25% to 35% of all patients. Because psychological factors, especially anger and vital exhaustion, have been found to increase the risk of new cardiac events after PTCA, a behavioral intervention might contribute to the reduction of the risk of restenosis. To investigate the operational and methodological aspects of a behavioral intervention, and to estimate the effect size of the risk reduction, we did a feasibility study of angioplasty patients who remained exhausted after PTCA. Breathing therapy was used as the main method for intervention. Thirty patients who participated in the intervention program and 65 controls were followed during an average period of 16 and 18 months, respectively. It was observed that the intervention resulted in a significant decrease of the mean exhaustion scores and reduced the risk of a new coronary event (cardiac death, coronary artery bypass grafting, myocardial infarction, rePTCA, restenosis) by 50% ((X)=2.19; p=0.13). These results indicate that a clinical trial to test the hypothesis that a reduction of vital exhaustion and hostility reduces the risk of a new cardiac event after PTCA, is feasible and merits the efforts required. (C) 1997 Elsevier Science Inc.