Atrial fibrillation (AF) and heart failure (HF) often coexist aggravating prognosis and constituting a major public health problem. The prevalence of AF especially in patients with chronic HF remains poorly understood in our country.

To assess the prevalence of AF in patients with HF recruited from the prospective NATURE-HF registry (NAtional TUnisian REgistry of Heart Failure).and to determine the clinical profile as well as the evolutionary modalities of this group.

Between October and November 2017, we prospectively registered 2040 patients with a history of HF. Patients with AF were picked. Clinical features, etiological characteristics, management as well as outcome were recorded within one year of follow-up.

Among 2040 patients with HF, 337 patients with a mean age of 65±13 years old presented with AF (16.5%). The frequency of cardiovascular risk factors associated with AF was: hypertension, diabetes, dyslipidemia and tobacco in respectively 42.9%, 29.8%, 20.8% and 19.7% of patients. The causes of underlying heart disease of HF associated with AF were: coronary artery diseases (30.4%), heart valve diseases (30.1%), primitive heart disease (24.7%); rythmic cardiopathy (12.8%) and hypertensive (1.2%). Over a follow-up of 12 months, there was no significant difference in terms of hospitalisation between HF patients with or without associated AF (6.3% vs. 7.5%, P=0.4). However, the presence of AF was associated with a worse prognosis in terms of mortality (17.9% in patients with AF compared to 12% in patients without AF, P=0.004) despite comparable clinical features to baseline with patients without AF.

NATURE HF showed that AF frequently appears in patients with HF and it occurs at an average age lower than that found in the literature. Otherwise, the results of NATURE HF emphasize that AF seems to worsen the prognosis in patients followed for HF.