The aim of this study was to assess the importance of congestive heart failure and left ventricular (LV) systolic dysfunction after an acute myocardial infarction (AIM) on long-term mortality in different age groups. A total of 7,001 consecutive enzyme-confirmed AMIs (6,676 patients) were screened for entry into the TRAndolapril Cardiac Evaluation (TRACE) study. Medical history, echocardiographic estimation of LV systolic function determined as wall motion index, infarct complications, and survival were documented for all patients. To study the importance of congestive heart failure and wall motion index independent of age, we performed Cox proportional-hazard models in 4 different age strata (< or = 55 years, 56 to 65 years, 66 to 75 years, and > 75 years). Patients in these strata had 1-year mortality rates of 5%, 11%, 21%, and 32%, respectively. Three-year mortality rates were 11%, 20%, 34%, and 55%, respectively. The risk ratios (and 95% confidence limits) associated with congestive heart failure in the same 4 age strata were 1.9 (1.3 to 2.9), 2.8 (2.1 to 3.7), 1.8 (1.5 to 2.2) and 1.8 (1.5 to 2.2), respectively. The risk ratios associated with decreasing wall motion index were 6.5 (3.6 to 11.4), 3.3 (2.3 to 4.6), 2.7 (2.2 to 3.4), and 2.1 (1.7 to 2.6), respectively. In absolute percentages, there was an excess 3-year mortality associated with congestive heart failure in the 4 age strata of 14%, 24%, 25%, and 28% respectively. The absolute excess in 3-year mortality associated with LV systolic dysfunction in the 4 age strata was 15%, 19%, 25%, and 21%, respectively. Thus, the relative importance of LV systolic dysfunction and congestive heart failure diminished with increasing age. However, the absolute excess mortality associated with congestive heart failure and LV systolic dysfunction was more pronounced in the elderly than in the young.