The aim of this study was to evaluate the results of predischarge stress testing in the elderly, and to assess the prognostic value of the test during one-year follow-up. The database consisted of 48 patients older than 64 years of age and 109 patients 55-64 years of age, who survived acute myocardial infarction, out of 532 consecutive patients admitted for myocardial infarction. Stress-test results were not different in the two groups. During one-year follow-up mortality was 6% in the younger patients and 4% in the older group, and the incidence of non-fatal reinfarctions was 8% in both groups. Mortality was best predicted by the extent of blood pressure rise (43 +/- 26 mmHg in survivors vs 19 +/- 15 mmHg in non-survivors, P less than 0.001). Stress-test results were no more predictive when non-fatal reinfarction was added to mortality as an end-point. We conclude that for patients in whom the stress test is not contraindicated, age does not affect stress test results, the extent of blood pressure rise during a stress test is the best single predictor of mortality, stress tests are not predictive of reinfarctions.