Antithrombotic treatment in patients with heart failure and associated atrial fibrillation and vascular disease: a nationwide cohort study.

OBJECTIVES:The aim of this study was to investigate the impact of atrial fibrillation (AF) and antithrombotic treatment on the prognosis in patients with heart failure (HF) as well as vascular disease. BACKGROUND:HF, vascular disease, and AF are pathophysiologically related, and understanding antithrombotic treatment for these conditions is crucial. METHODS:In hospitalized patients with HF and coexisting vascular disease (coronary artery disease or peripheral arterial disease) followed from 1997 to 2009, AF status was categorized as prevalent AF, incident AF, or no AF. Risk of thromboembolism (TE), myocardial infarction (MI), and serious bleeding was assessed by Cox regression models (hazard ratio [HR] with 95% confidence interval [CI]) with antithrombotic therapy and AF as time-dependent variables. RESULTS:A total of 37,464 patients were included (age, 74.5 ± 10.7 years; 36.3% females) with a mean follow-up of 3 years during which 20.7% were categorized as prevalent AF and 17.2% as incident AF. Compared with vitamin K antagonist (VKA) in prevalent AF, VKA plus antiplatelet was not associated with a decreased risk of TE (HR: 0.91; 95% CI: 0.73 to 1.12) or MI (HR: 1.11; 95% CI: 0.96 to 1.28), whereas bleeding risk was significantly increased (HR: 1.31; 95% CI: 1.09 to 1.57). Corresponding estimates for incident AF were HRs of 0.77 (95% CI: 0.56 to 1.06), 1.07 (95% CI: 0.89 to 1.28), and 2.71 (95% CI: 1.33 to 2.21) for TE, MI, and bleeding, respectively. In no AF patients, no statistical differences were seen between antithrombotic therapies in TE or MI risk, whereas bleeding risk was significantly increased for VKA with and without single-antiplatelet therapy. CONCLUSIONS:In AF patients with coexisting HF and vascular disease, adding single-antiplatelet therapy to VKA therapy is not associated with additional benefit in thromboembolic or coronary risk, but notably increased bleeding risk.