Prevalence and risk factors of silent brain infarcts in patients with AF detected by 3T-MRI

Abstract

Background Silent brain infarcts (SBI), a fnding on neuroimaging, are associated with higher risk of future stroke. Atrial Fibrillation (AF) has been previously identifed as a cause of SBI. Objectives The aim of this study is to determine the prevalence of and risk factors for SBI in patients with AF and low-tomoderate embolic risk according to CHADS2 and CHA2DS2VASc score. Methods Patients with a history of AF based on medical records who scored 0–1 in the CHADS2 score were selected from the Seville urban area using the Andalusian electronic healthcare database (DIRAYA). Demographic and clinical data were collected and a 3T brain MRI was performed on patients older than 50 years and with absence of neurological symptoms. Results 66 of the initial 443 patients (14.9%) and 41 of the 349 patients with low risk according to CHA2DS2VASc score (11.7%) presented at least 1 SBI. After adjusted multivariable analysis, an older age (OR 3.84, 95% CI 1.07–13.76) and left atrial (LA) enlargement (OR 3.13, 95% CI 1.15–8.55) were associated with SBI in the whole cohort, while only LA enlargement was associated with SBI in the low-risk cohort (OR 3.19, 95% CI 1.33–7.63). Conclusions LA enlargement on echocardiogram was associated with SBI in patients with AF and low or moderate embolic risk according to CHADS2 and in the low-risk population according to CHA2DS2VASc. Although further studies are needed, a neuroimaging screening might be justifed in these patients to guide medical therapies to improve stroke prevention.