Abstract 12077: Stroke as the First Manifestation of Atrial Fibrillation

Introduction: Atrial fibrillation (AF) may remain undiagnosed until an ischemic stroke occurs. In this retrospective cohort study we assessed the prevalence of ischemic stroke or transient ischemic attack (TIA) as the first manifestation of AF in a cohort of patients with AF-associated stroke or TIA. Methods: Altogether 3,623 patients treated for their first ever ischemic stroke or TIA during 2003-2012 were identified from the electronic patient records of four clinical centers. Two groups were formed: patients with a history of AF and patients with new AF diagnosed during hospitalization for stroke or TIA. A control group of 781 patients with intracranial hemorrhage was compiled similarly to explore the direction of causality between new AF and stroke. Results: The median age of the patients was 78.3 [13.0] years and 2,009 (55.5%) were women. New AF was diagnosed in 753 (20.8%) patients with stroke or TIA, compared to 15 (1.9%) with intracranial hemorrhage. Younger age (odds ratio [OR]: 1.01; 95% confidence interval [CI]: 1.00-1.02; p=0.014) and no history of coronary artery disease (OR: 1.45; 95% CI: 1.16-1.82; p=0.001) or other vascular diseases (OR: 1.75, 95% CI: 1.09-2.79. p=0.020), heart failure (OR: 2.62; 95% CI: 1.94-3.54, p<0.001), or hypertension (OR: 1.22; 95% CI:1.01-1.47; p=0.041) were the independent predictors of new AF detected concomitantly with an ischemic event. Thus, ischemic stroke was the first clinical manifestation of AF in 37% of younger (<75 years) patients with no history of cardiovascular diseases (Figure). Conclusions: In conclusion, AF is too often diagnosed only after an ischemic stroke has occurred, especially in middle-aged healthy individuals. New AF seems to be predominantly the cause of the ischemic stroke and not triggered by the acute cerebrovascular event.