Cardiovascular Biomarkers during Acute Periods of Ischemic Stroke due to Non-Valvular Atrial Fibrillation

Background A subanalysis study of the ENGAGE AF-TIMI 48 trial showed that cardiac troponin I, N-terminal proB-type natriuretic peptide, and D-dimer, were powerful predictors of cerebrovascular adverse events. We aimed to evaluate D-dimer and cardiac troponin I levels during the acute period of ischemic stroke in anticoagulation-naïve patients with non-valvular atrial fibrillation (NVAF) and also studied the association between these biomarkers and stroke severity. Methods Consecutive anticoagulation-naïve patients with acute ischemic stroke due to NVAF were enrolled within two days after each stroke event, and all patients were stratified into either moderate-to-severe or mild neurologic deficit groups using the National Institutes of Health Stroke Scale (NIHSS) at admission. Results A total of 98 patients were enrolled in this study. The median value for the D-dimer was above the upper limit of the normal reference range, but the troponin I value was within the normal range for all patients. After adjusting for CHA2DS2-VASc risk factors, the log-transformed values for D-dimer were positively correlated with an increasing NIHSS score (r=0.233; P=0.051). In the multivariate logistic analysis, the log-transformed D-dimer was positively associated with more severe strokes (odds ratio, 30.1; 95% confidence interval [CI], 1.9-486.2 and 29.7; 95% CI, 2.0-430.8 in the upper two quartiles respectively). The log-transformed values for troponin I did not correlate with the NIHSS score. Conclusion D-dimer levels were higher and an independent risk factor for severe stroke in anticoagulation-naïve patients with NVAF related stroke. In contrast, troponin I levels were normal and were not associated with stroke severity.