Abstract
Background: Atrial fibrillation (AF) may be detected at the time of ischemic stroke or newly detected after stroke. While AF detected after stroke (AFDAS) is associated with poor outcomes compared to sinus rhythm, its prognostic implications relative to known-AF are inconsistent. High-sensitivity cardiac troponin (hs-cTn) is a biomarker of myocardial injury, but its role in predicting AFDAS in stroke patients is unclear. We aimed to evaluate hs-cTn as a predictor for AFDAS and to compare all-cause death, readmission for heart failure (HF) and readmission for stroke among patients with non-AF, AFDAS, and known-AF in the post-ischemic stroke period. Methods: From August 2014 to July 2017, 1506 patients with acute ischemic stroke were consecutively enrolled in a retrospective single-center registry. Out of these, 1019 patients were selected for analysis. The primary outcome was major adverse cardiac and cerebrovascular events (MACCE), a composite of all-cause death, HF-caused readmission, or stroke-caused readmission during follow-up. Results: Out of 1019 ischemic stroke patients, 121 (13.8%) developed AFDAS over a median of 22.5 months; 135 had known-AF and 763 were maintained sinus rhythm during follow-up. Elevated hs-TnI (≥99th percentile), age > 75, and left atrial volume index >34 mL/m(2) independently predicted AFDAS. Both AFDAS and known-AF groups had a significantly increased risk of MACCE compared to the non-AF group (adjusted hazard ratio (HR) 1.85 and 1.76, respectively; p < 0.05 for both). The known-AF group also had a higher risk of all-cause mortality (adjusted HR 2.05, p = 0.02). The risks for MACCE and all-cause death did not differ significantly between the AFDAS and known-AF groups. Conclusions: An elevated hs-TnI level is independently associated with development of AFDAS and may serve as a valuable marker for stratifying the risk of future cerebrocardiovascular events following ischemic stroke.