Abstract 2391: Are Elevated Levels of Troponin T in Acute Ischemic Stroke Due to Myocardial Infarction?
Introduction: The pathophysiological mechanisms underlying elevated levels of troponin during acute ischemic stroke have not been clarified.
Hypothesis: We assessed the hypothesis that reported elevated troponin levels during an acute ischemic stroke may in part be due to an unnoticed myocardial infarction.
Methods: In 244 patients with an acute ischemic stroke but without known ischemic heart disease, Troponin T (TnT) and creatine kinase-MB (CK-MB) concentrations were measured and a 12 - lead ECG was obtained on a daily basis during the first 5 days of admission. Myocardial perfusion scintigraphy (MPS) was performed in patients with TnT levels ≥0.10 μg/L and in control patients without elevation of TnT. The patients were followed for a mean of 19 ± 7 months with all cause mortality as the clinical end-point.
Results: Elevated levels of TnT (>0.03 μg/L) and CK-MB (≥10.00 μg/L) were observed in 10 % and 9 % of the patients, respectively. Patients with elevated TnT frequently had heart- and/or renal failure. MPS perfusion abnormalities were not more frequent or pronounced in patients with levels of TnT ≥0.10 μg/L than in the control group. Only 7 patients (3 %) had elevation of TnT or CK-MB and ST-T changes with a pattern suggesting an acute myocardial infarction. In Cox analysis, patients with TnT elevation (>0.03 μg/L) had a significantly increased mortality compared to patients without TnT elevation (HR=3.39; [95 % CI, 1.34 – 8.60], p<0.01) with adjustment for age, stroke severity, heart- and/or renal failure.
Conclusion: In 10% of patients presenting with an acute ischemic stroke elevated levels of TnT can be demonstrated. However, in only one third of the cases the diagnosis of an acute myocardial infarction is likely. When present, TnT elevation is useful in identifying patients at heightened risk of mortality during up to 2 years of follow-up.