Atrial fibrillation in heart failure is associated with an increased risk of death only in patients with ischaemic heart disease

The prognostic importance of atrial fibrillation (AF) in heart failure (HF) populations is controversial and may depend on patient selection. In the present study, we investigated the prognostic impact of AF in a large population with HF of various aetiologies. We included 2881 patients admitted to hospital with symptoms of worsening HF over a 4-year period (2001-2004), all patients were participants in the Echocardiography and Heart Outcome Study (ECHOS). Patients were followed for up to 7 years for all-cause mortality stratified according to heart rhythm (sinus rhythm, paroxysmal, or chronic AF) and according to the presence of ischaemic heart disease (IHD). During follow-up, 1934 patients (67%) died. In HF patients with a history of IHD, chronic AF was associated with an increased risk of death [hazard ratio (HR) 1.44; 95% confidence interval (CI): 1.18-1.77; P < 0.001). In contrast, in patients without IHD, chronic AF was not associated with an increased mortality risk (HR 0.88; 95% CI: 0.71-1.09; P = 0.25). There was significant interaction between the aetiology of HF and the prognostic importance of chronic AF (P-interaction = 0.003). In patients with HF, AF is associated with an increased risk of death only in patients with underlying IHD.