From November 1988 to May 1992, 108 patients (79 men, 29 women) 75 years or older (mean 78 +/- 3, range 75-90 years) underwent coronary angioplasty (group I: n = 62) or coronary bypass surgery (group II: n = 46). Group II patients were younger (76 +/- 2 vs 79 +/- 4, P = 0.002) and had a higher proportion of multivessel disease. The two groups were comparable with regard to the presence of unstable angina, left ventricular ejection fraction and Q wave infarction. In-hospital mortality was similar in the two groups (6.4% vs 4.3%). Complete revascularization (72% vs 47%, P < 0.05) and left anterior descending artery revascularization (100% vs 45%, P < 0.01) were more frequent in group II. Two-year infarction-free survival was similar (group I: 76 +/- 6%; group II: 79 +/- 6%) but recurrent class III or IV angina (36% vs 9%, P < 0.05) and repeat procedures (26% vs 0%, P < 0.05) were more frequent in group I.