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.