Ffity-five patients with recurrent severe angina pectoris at rest that was resistant to medical therapy were treated with intraaortic balloon pumping (IABP), angiography, and vein bypass surgery. There were 25 patients with typical angina with ST depression during pain, 12 with Prinzmetal's angina, and 18 patients with angina in the early recovery phase following "transmural" myocardial infarction. The severity and frequency of ischemic attacks were documented with hemodynamic and continuous electrocardiographic monitoring. A marked reduction in both frequency and intensity of attacks was produced by IABP. Temporary cessation of IABP resulted in rapid recurrence of angina in 40% of patients. All underwent selective coronary angiography and revascularization surgery. The overall mortality was 5.5% and the incidence of intraoperative myocardial infarction was under 2%. Follow-up evaluation after an average of 18 months has shown no late deaths and sustained clinical improvement.