Does heart rate really matter to patients with heart failure?

Purpose of review Measurement of heart rate (HR) and rhythm is used to identify patients at increased risk of disease progression, guide selection of treatments and gauge response to therapy. Recent findings Lowering HR with a pure HR lowering agent (ivabradine) in heart failure with reduced ejection fraction (HFrEF) and sinus rate more than 70 beats/min despite beta blockade has been shown to improve outcomes. Additionally, coadministration of ivabradine and beta blockade may enhance symptoms and HR control. In the case of patients with heart failure and preserved ejection fraction (HFpEF), or with paced rhythm, optimal HR control is not known. Also, in atrial fibrillation the relationship between HR and outcomes is not clear and minimal evidence for HR reduction to less than 100 beats/min exists. Reasons for this disconnect between atrial fibrillation and sinus rhythm are not known. Summary HR continues to be a critical vital sign in assessment and forms the basis for a treatment target in patients with HFrEF at rates more than 70 beats/min. The target for HR patients with HFpEF and those who are paced continuously or in atrial fibrillation is less clear and at present is recommended to be in the 60-100 beats/min range at rest. Further study is needed to refine treatment strategies in these latter patients.