Elderly patients have a higher mortality after acute myocardial infarction (MI) yet are treated less aggressively than younger patients. To determine (l) the risk-factor profiles, (2) presentation, (3) management, and (4) hospital outcomes for the elderly (> or = 75 years) compared with middle aged (66 to 74 years) and younger (< or = 65 years) patients in the 1990s, we studied 561 consecutive patients with acute MI. Compared with younger patients, the elderly more frequently had congestive heart failure (40 percent vs 14 percent; p < 0.00001) and non-Q wave infarctions (76 percent vs 56 percent; p < 0.005), received thrombolysis (9 percent vs 34 percent; p < 0.0001), and underwent catheterization (35 percent vs 73 percent; p < 0.00001), percutaneous transluminal coronary angioplasty (9 percent vs 31 percent; p < 0.0002), and coronary artery bypass grafting (5 percent vs 15 percent; p < 0.03) less frequently. Those who did not receive thrombolysis all had contraindications. Mortality was higher in the elderly (19 percent vs 5 percent; p < 0.004), especially among those who did not receive thrombolysis (20 percent vs 7 percent; p < 0.03). Multivariate predictors of mortality included age, and congestive heart failure. In addition, when clinical course and management variables were considered, use of the intraaortic balloon pump was a predictor of mortality, whereas undergoing coronary angiography was a negative predictor (relative risk, 0.3; 95 percent confidence intervals, 0.1 to 0.6).