Risk of embolic events in patients with Chagasic Cardiomyopathy and Atrial Fibrillation despite antithrombotic therapy: is anticoagulation enough?

Abstract Background Chagasic cardiomyopathy (CC) differs from other heart failure causes in multiple aspects, highlighting the risk of systemic embolisms. However, few studies have evaluated the risk of embolic events in anticoagulated patients with CC compared to other cardiomyopathies. Objective We aimed to analyze the incidence of systemic embolisms in a cohort of anticoagulated patients diagnosed with atrial fibrillation (AF) with and without CC. Methods A retrospective cohort study was conducted at a fourth-level hospital from 2014-2020. All patients diagnosed with cardiomyopathy of any etiology and AF on an anticoagulation regimen were included. The primary outcome was the incidence of embolic events. A survival analysis was performed using adjusted Cox proportional hazard models. A p-value of <0.05 was considered significant. All statistical tests were two-tailed. Results 149 anticoagulated patients with cardiomyopathy were evaluated (median age: 71 years; women: 30.20%). The cumulative incidence of embolic events was significantly higher in patients with CC (17.50%) compared to those with other cardiomyopathies (4.95%), despite that the latter had a substantially higher CHA2DS2-VASc score (p=0.013). After multivariate analysis, patients with CC had a significantly higher risk of embolic events regardless of the CHA2DS2-VASc score and the anticoagulant prescribed (HR 5.65. 95% CI 1.46-21.83; p=0.012). Conclusions CC was associated with a significantly higher risk of embolic events despite anticoagulation therapy in both groups. More research is required to understand the origin of this risk observed to translate this knowledge into specific indications for anticoagulation for patients with CC.Cumulative incidence of embolic events