Association between acute heart failure and major cardiovascular events in atrial fibrillation patients presenting at the emergency department: an EMERG-AF ancillary study

Background There is little evidence concerning the impact of acute heart failure (AHF) on the prognosis of atrial fibrillation patients attending the emergency department (ED). Objective To know the influence of AHF on adverse long-term outcomes in patients presenting with atrial fibrillation in ED. Design, setting and participants Secondary analysis of a prospective, multicenter, observational cohort of consecutive atrial fibrillation patients, performed in 62 Spanish EDs. Exposure Patients presenting with atrial fibrillation in ED were divided by the presence or absence of AHF at arrival. Outcome measures and analysis Primary outcome: combination of 1-year all-cause mortality, major bleeding, stroke and other major cardiovascular events (MACE). Secondary outcomes: each of these events analyzed separately. Cox and logistic regression were used to investigate adjusted significant associations between AHF and outcomes. Main results Totally, 1107 consecutive ED patients with atrial fibrillation attending ED were analyzed, 262 (23.7%) with AHF. The primary outcome occurred in 433 patients (39.1%), 1-year all-cause mortality in 151 patients (13.6%), major bleeding in 47 patients (4.2 %), stroke in 31 patients (2.8 %) and other MACE in 333 patients (30.1%). AHF was independently related to the primary outcome [odds ratio (OR), 1.422; 95% confidence interval (CI), 1.020-1.981; P = 0.037)] and 1-year MACE (OR, 1.797; 95% CI, 1.285-2.512; P = 0.001), but not to 1-year all-cause mortality, stroke or bleeding. Conclusions The coexistence of AHF in patients presenting with atrial fibrillation in ED is associated to a worse 1-year outcome mainly due to MACE, but does not impact in overall mortality.