This study was undertaken to test the hypothesis that percutaneous transluminal coronary angioplasty (PTCA) is a reasonable alternative to coronary artery bypass grafting (CABG) for some high-risk patients with medically refractory rest angina. Over a 5-year period, 1 operator at a tertiary Veterans Affairs Medical Center performed angioplasty on 624 patients, of whom 441 had unstable angina. Of these 441 patients, 288 had rest angina and 225 had medically refractory rest angina. Medically refractory unstable angina was defined as reversible myocardial ischemia occurring at rest in an intensive care unit setting with low flow oxygen despite the following medications: (1) oral aspirin, intravenous heparin, or both; (2) some combination of beta blocker, calcium blocker, and/or nitrate so that resting heart rate is < 70 beats/min or resting blood pressure < 140 mm Hg, or both. There were 207 patients with medically refractory rest angina who had > or = 1 of the following characteristics predictive of a more than twofold increased risk of operative death at CABG: age > 70 years, prior CABG, recent myocardial infarct, need for intravenous nitroglycerin, need for intraaortic balloon pump, and left ventricular ejection fraction < 0.35. Of these 207 patients, 11 died (5%) during index hospitalization, 196 (95%) were discharged, and 186 (90%) went home angina free. There were 2 emergency CABGs and 9 acute myocardial infarctions. At follow-up (3 to 60 months, average 24), there were 27 late deaths (for a total of 38 [18%]), 8 (4%) late CABGs, and 44 (21%) late PTCAs (with 17 [8%] late myocardial infarctions). The 2-year mortality of 18% for this cohort is comparable to a 21% 2-year mortality observed in a group of 1,073 "high-risk" patients who underwent CABG in the Veterans Affairs Medical Center from 1987 to 1988. These data support the hypothesis that PTCA provides an alternative to CABG in some high-risk patients with medically refractory rest angina.