Atrial fibrillation (AF) is frequently associated with heart failure and reduced ejection fraction (HFrEF) with a harmful interaction of these two pathologies. The prevalence of their association and its prognosis remains poorly understood in our country.

The objective of this study is to assess the prevalence of AF in patients with HFrEF, to determine their epidemiological characteristics and their evolutionary profile after optimization of their therapies.

We conducted a prospective monocentric therapeutic follow-up study with a minimum follow-up of 1 year for each recruited patient. We included patients over the age of 18 with chronic and symptomatic HFrEF.

During the study period, 252 patients were recruited. We find in the general population a clear predominance of men with a sex ratio of 2.4 and an average age of 59 years.The prevalence of AF in patients with HFrEF was 24.6%. The frequency of cardiovascular risk factors associated with AF was 45% for arterial hypertension, 25.8% for diabetes, and 27.4% for tobacco. The etiology of the HFrEF associated with AF was: ischemic in 25.8% of cases and valvular in only 16.1%. Atrial fibrillation was associated with lower functional capacity and increased physical signs of HF: the majority of patients with AF (70%) were at stage III of NYHA at baseline versus 53.6% of patients with sinus rhythm (SR). The evolution was favourable at 1 year after optimization of the treatment (86% were in stage I/II of NYHA, 90% of patients with SR. The crude mortality and HF hospitalization rates were higher in the patients with AF with a death rate of 25.8% compared to 16.3% in the SR group and a hospitalization rate for cardiovascular cause of around 28% in the group with AF compared to 12% in the group with SR.

Atrial fibrillation is common in the HFrEF patient population in our study and with a more severe prognosis.