To examine the role of percutaneous transluminal coronary angioplasty (PTCA) in patients with silent ischemia, 50 consecutive patients (mean age 54 years, 88% men) with 1-vessel disease and absent or minimal symptoms who underwent PTCA were identified. Nineteen patients (38%) were asymptomatic and 31 patients (62%) had minimal angina (at most 1 episode/month, and with marked exertion only). Exercise-induced ischemia was present in 45 of 49 patients (92%) tested. The remaining 5 patients had a critical stenosis in a vessel supplying a large myocardial territory. A total of 75 lesions were dilated, 71 successfully (95%). There were no procedural deaths or infarctions. The single complication was an urgent bypass operation. After PTCA, only 3 of 46 patients exercised (7%) had inducible ischemia (p less than 0.0005 vs before PTCA). At a mean follow-up of 36 months, 46 of 49 patients alive (94%) were asymptomatic (p less than 0.0005 vs before PTCA). The 3-year actuarial survival and infarct-free survival were 98 and 96%, respectively. However, 5 patients (10%) crossed over to bypass surgery and 14 patients (28%) underwent repeat PTCA. Progression of native coronary disease was present in 9 of these patients (47%). As in symptomatic patients, elective PTCA can be performed safely and with a high success rate in patients with silent ischemia, and can markedly reduce the incidence of exercise-induced ischemia. With this approach, greater than 90% of the patients were asymptomatic at the 3-year follow-up; however, 34% required a further revascularization procedure for restenosis or progression of native disease or both.(ABSTRACT TRUNCATED AT 250 WORDS)