Heart Rate Reduction and Outcomes in Heart Failure Outpatients

Aim. Pharmacologic reduction in heart rate with beta-blockers (BB) or ivabradine is associated with improved survival in heart failure (HF) with sinus rhythm. We analyzed the association of different heart rate-reducing drug treatments on outcomes in HF outpatients. Methods. Consecutive patients with HF in sinus rhythm referred to a specialized tertiary service were prospectively enrolled from August 2015 until March 2018. Clinical characteristics were assessed at baseline. We performed Cox regression analyses to examine the effect of the resting heart rate and different heart rate-reducing drug regimens on all-cause mortality and a composite endpoint of "all-cause mortality or heart transplantation" over a mean follow-up of 3.1 years. Results. Of the 278 patients included, 213 (76.6%) were male, the median age was 57.0 years (IQR 49.0-66.1), and 185 (73.7%) had an ejection fraction <40%. Most patients received BB in submaximal [n = 118] or maximum dose [n = 136]. Patients on BB in maximum dose plus ivabradine [n = 24] were younger (53.0 vs. 58.0 years) and had a lower EF (25 vs. 31%). Higher resting heart rate was associated with an increased risk of death or transplantation (HR 1.03 [1.01, 1.06], p = 0.0072), even after adjusting for age and sex. There were no differences between the groups concerning all-cause mortality or the composite endpoint. Conclusion. Our prospective study confirms the association between low heart rate and survival in HF patients receiving various heart rate-reducing medications. We could not identify a specific effect of either regimen.