AIMS: The objective of the study was to investigate the influence of a history of arterial hypertension on long-term prognosis after an acute myocardial infarction in a representative population, and secondly to assess the impact on prognosis of left ventricular systolic function in hypertensives after acute myocardial infarction. METHODS: A retrospective analysis of survival data on 6676 patients with acute myocardial infarction screened for entry into the TRAndolapril Cardiac Evaluation (TRACE) study. Follow-up time was 4-6 years. RESULTS: One thousand five hundred and seven (23%) of the patients had a history of arterial hypertension. During the time of observation 763 (50.6%) hypertensives and 2253 (43.7%) normotensives died, corresponding to a risk ratio for death in hypertensives of 1.23 (1.13-1.33, P < 0.0001). In a multivariate analysis considering 12 other major risk factors after myocardial infarction, the risk ratio for death in hypertensives was 1.14 (1.04-1.24). There was a significant interaction between hypertension and age. Thus, hypertension only increased risk in patients aged 65 years or less (P < 0.001). No interaction with left ventricular systolic function was found. CONCLUSION: A history of arterial hypertension is a moderate risk factor for mortality after an acute myocardial infarction in patients aged 65 years or less. This excess risk is present at all levels of left ventricular systolic function.