Heart failure (HF) and atrial fibrillation (AF) often coexist, being 
closely interrelated as the one increases the prevalence and incidence 
and worsens the prognosis of the other. Their frequent coexistence 
raises several challenges, including under-diagnosis of HF with 
preserved ejection fraction in AF and of AF in HF, characterization and 
diagnosis of atrial cardiomyopathy, target and impact of rate control 
therapy on outcomes, optimal rhythm control strategy in the era of 
catheter ablation, HF-related thromboembolic risk and management of 
anticoagulation in patients with comorbidities, such as chronic kidney 
disease or transient renal function worsening, coronary artery disease 
or acute coronary syndromes, valvular or structural heart disease 
interventions and cancer. In the present document, derived by an expert 
panel meeting, we sought to focus on the above challenging issues, 
outlining the existing evidence and identifying gaps in knowledge that 
need to be addressed.