Elevated levels of troponin have been reported in patients with acute ischemic stroke. In this prospective study, the prevalence and characteristics of troponin elevation were examined in 244 patients with acute ischemic stroke but without overt ischemic heart disease. Troponin T (TnT) and creatine kinase-MB (CK-MB) concentrations were measured and 12-lead electrocardiograms obtained daily during the first 5 days of admission. Myocardial perfusion scintigraphy was performed in patients with TnT levels of 0.10 micro g/L and in comparable controls without elevation of TnT. Patients were followed for a mean of 19 +/- 7 months, with all-cause mortality as the clinical end point. Elevated levels of TnT (>0.03 micro g/L) and creatine kinase-MB (> or =10 micro g/L) were observed in 10% and 9% of patients, respectively. Patients with elevated TnT had higher frequencies of heart and/or renal failure. Perfusion abnormalities on myocardial perfusion scintigraphy at rest were not more frequent or pronounced in patients with TnT levels of > or =0.10 micro g/L than in the control group. Only 7 patients (3%) had elevations of TnT or creatine kinase-MB and electrocardiographic changes suggesting acute myocardial infarctions. According to univariate and multivariate analyses, elevation of TnT was significantly associated with mortality. In conclusion, elevated levels of TnT are rare in patients presenting with ischemic stroke but without overt ischemic heart disease. Heart and renal failure rather than myocardial infarction are the most likely causes. When present, elevation of TnT seems to be useful in identifying patients who are at increased risk of dying within the following 2 years.