Impact of atrial fibrillation and the clinical outcomes in patients with acute myocardial infarction from the K-ACTIVE registry

Abstract

BackgroundThe clinical incidence and impact of atrial fibrillation (AF) in Japanese acute myocardial infarction (AMI) patients is not fully understood. MethodsTo elucidate the clinical incidence and impact of AF on in-hospital mortality in AMI patients, we analyzed a Japanese observational prospective multicenter registry of acute myocardial infarction (K-ACTIVE: Kanagawa ACuTe cardIoVascular rEgistry), which spans 2015 to 2019. A major adverse cardiac event (MACE) was defined as cardiovascular death, non-fatal myocardial infarction (MI), and non-fatal stroke. For assessing bleeding events, Bleeding Academic Research Consortium (BARC) type 3 or 5 was used. MACE plus BARC type 3 or 5 bleeding were considered as composite events. The clinical outcomes were followed for 1 year. ResultsThe total of 5059 patients included 531 patients with AF (10.5%) and 4528 patients with sinus rhythm (SR; 89.5%). AF patients were significantly older and tended to have more comorbidities than SR patients. Oral anticoagulation therapy (OAC) was used in 44% of AF patients while single antiplatelet therapy was selected for 52% of patients with OAC. Crude in-hospital mortality was significantly greater in AF patients than in SR patients (10.4%, 5.0%, respectively, p < 0.01). The multivariate analysis was adjusted for age, sex, diabetes, hypertension, hemodialysis, smoking, previous MI, body mass index, Killip classification, out of hospital cardiac arrest, and OAC. In-hospital mortality was still significantly greater in AF patients than in SR patients in the logistic regression analysis [adjusted odds ratio 2.02 (1.31–3.14)]. AF was an independent risk factor for MACE and composite events in the Cox proportional hazards model [adjusted risk ratio (ARR) 1.91 (1.36–2.69), p < 0.01; ARR 1.72 (1.25–2.36), p < 0.01]. In contrast, AF was not an independent risk factor for bleeding [ARR 1.71 (0.79–3.71), p = 0.18]. ConclusionIn Japanese AMI patients, AF was often observed and was associated with worse MACE but not worse bleeding.