Effects of atrial fibrillation on long-term outcomes in patients hospitalized for heart failure in Japan - A report from the Japanese Cardiac Registry of Heart Failure in Cardiology (JCARE-CARD)

Background: Atrial fibrillation (AF) is a common arrhythmia in patients with heart failure (HF), but its prognostic importance is controversial. The effect of AF on long-term outcomes, including mortality and rehospitalization, among unselected HF patients hospitalized with HF in routine clinical practice in Japan was assessed in the present study. Methods and Results: The Japanese Cardiac Registry of Heart Failure in Cardiology (JCARE-CARD) prospectively studied the characteristics and treatment strategies of a broad sample of patients hospitalized with worsening HF and the outcomes were followed with an average of 2.4 years of follow-up. The study cohort (n=2,659) was grouped according to the presence (n=937; 35.2%) or absence (n=1,722; 64.8%) of AF at baseline. After multivariable adjustment, patients with and without AF had a comparable risk for all-cause death (adjusted hazard ratio (HR) 0.931, 95% confidence interval (CI) 0.690-1.258, P=0.643), cardiac death (adjusted HR 0.949, 95%CI 0.655-1.377, P=0.784), rehospitalization because of the worsening HF (adjusted HR 1.028, 95%CI 0.816-1.295, P=0.816), and all-cause death or rehospitalization (adjusted HR 1.039, 95%CI 0.842-1.281, P=0.722). Conclusions: Among patients hospitalized for HF in Japan, AF was common, but was not an independent risk for long-term adverse outcomes, including death or rehospitalization, in routine clinical practice.