Prognostic significance of changes in heart rate following uptitration of beta-blockers in patients with sub-optimally treated heart failure with reduced ejection fraction in sinus rhythm versus atrial fibrillation

Background In patients with heart failure with reduced ejection fraction (HFrEF) on sub-optimal doses of beta-blockers, it is conceivable that changes in heart rate following treatment intensification might be important regardless of underlying heart rhythm. We aimed to compare the prognostic significance of both achieved heart rate and change in heart rate following beta-blocker uptitration in patients with HFrEF either in sinus rhythm (SR) or atrial fibrillation (AF).