Clinical benefits and risks of antithrombotic therapy in patients with atrial fibrillation with comorbidities – A report from the CHART-2 Study

Background: The benefits of antithrombotic therapy (ATT) for atrial fibrillation (AF) are occasionally offset by major bleeding complications. However, the clinical benefits and risks of ATT in AF patients, with special references to comorbidities, such as heart failure (HF), coronary artery disease (CAD), and the patterns of AF, remain to be fully elucidated. Methods: A total of 3221 consecutive AF patients from our Chronic Heart Failure Analysis and Registry in the Tohoku District-2 (CHART-2) Study (N = 10,219) were divided into 4 groups based on ATT at enrollment; no-ATT, anticoagulant alone, antiplatelet alone, and both of them (AC&AP). Then, efficacy and safety outcomes including thromboembolic events, major bleeding, and mortality were evaluated among the 4 groups. Results: Anticoagulant monotherapy was associated with reduced risk of ischemic stroke in patients with but not in those without HF, CAD, or non-paroxysmal AF. Although there was no significant difference in major bleeding among the 4 groups, a composite of thromboembolism and major bleeding occurred more frequently in the AC&AP group, even in combination with anticoagulants and single antiplatelet therapy, indicating that the combination therapy is more harmful than anticoagulant monotherapy for AF patients, especially for those with HF or CAD. Lastly, no-ATT group was associated with worse prognosis compared with other 3 groups. Conclusions: These results indicate that ATT is beneficial for AF patients particularly for those with HF, CAD, or non-paroxysmal AF and that among ATT, anticoagulant monotherapy may be most profitable for both clinical benefits and risks for AF patients.