Can prolonged QTc and cTNT level predict the acute and long-term prognosis of stroke?

Abstract

Background: Previous studies in patients with stroke indicate that QTc prolongation and elevated cTNT are related to increased risk of all-cause and cardiovascular mortality.

Methods: We analysed the importance of electrocardiographic (ECG) abnormalities and elevated serum cardiac troponin (cTNT)--at baseline examination--as potential predictors for acute and long-term mortalities after stroke in a follow-up of 478 patients with a mean age of 78 years.

Results: In a multivariate analysis, strong predictors for poor prognosis during the acute phase were: elevated cTNT (p=0.001); stroke severity (p=0.004); ischemia on ECG (p=0.044); and age (p=0.050). Prolonged QTc interval was on the limit to statistical significance (p=0.050) when using multivariate analysis, while clearly significant in a Cox-regression (when corrected for missing cTNT values). One year after stroke, when adjusted for covariates (gender, diabetes mellitus, hypertension, and ischemic heart disease), elevated cTNT (p=0.001), stroke severity (p=0.014), and age (p=0.031) retained a significant relation with mortality. Moreover, atrial fibrillation was strongly correlated with poor survival (p=0.009). Cox regression confirmed the predictive value of QTc, cTNT, age, and stroke severity, as markers of acute mortality in relation to stroke.

Conclusion: Prolonged repolarization time independently predicts poor prognosis during the acute phase, but not one year after stroke. In the absence of acute myocardial infarction, elevated initial cTNT is strongly related to poor outcome, both during the acute phase and one year after stroke.