Prognostic significance of remotely monitored nocturnal heart rate in heart failure patients with reduced ejection fraction

Heart Rhythm. 2023 Feb;20(2):233-240. doi: 10.1016/j.hrthm.2022.10.018. Epub 2022 Oct 28.

Abstract

Background: Elevated resting heart rate is a risk factor for cardiovascular events.

Objective: The purpose of this study was to investigate the clinical significance of nocturnal heart rate (nHR) and 24-hour mean heart rate (24h-HR) obtained by continuous remote monitoring (RM) of implantable devices.

Methods: We analyzed daily-sampled trends of nHR, 24h-HR, and physical activity in patients on β-blocker therapy for chronic heart failure and with implantable cardioverter-defibrillators or cardiac resynchronization therapy defibrillators (CRT-Ds). Patients were grouped by average nHR and 24h-HR quartile during follow-up to estimate the respective incidence of nonarrhythmic death and device-treated ventricular tachycardia/fibrillation (VT/VF).

Results: The study cohort included 1330 patients (median age 69 years [interquartile range 61-77 years]; 41% [n = 550] with CRT-D; median follow-up 25 months [interquartile range 13-42 months]). Compared with patients in the lowest nHR quartile (≤57 beats/min) group, patients in the highest quartile group (>65 beats/min) had an increased risk of nonarrhythmic death (adjusted hazard ratio [AHR] 2.25; 95% confidence interval [CI] 1.13-4.50; P = .021) and VT/VF (AHR 1.98; 95% CI 1.40-2.79; P < .001) and were characterized by the lowest level of physical activity (P ≤ .0004 vs every other nHR quartiles). The highest 24h-HR quartile group (>75 beats/min) showed an increased risk of VT/VF (AHR 2.13; 95% CI 1.52-2.99; P < .001) and a weaker though significant association with nonarrhythmic mortality (AHR 1.80; 95% CI 1.00-3.22; P = .05) as compared with the lowest 24h-HR quartile group (≤65 beats/min).

Conclusion: In remotely monitored patients with implantable cardioverter-defibrillator/CRT-D on β-blocker therapy for heart failure, elevated heart rates (nHR >65 beats/min and 24h-HR >75 beats/min) were associated with increased mortality and VT/VF risk. nHR showed a stronger association than 24h-HR with worst prognosis and lowest physical activity.

Keywords: Heart failure; Heart rate; Implantable cardioverter-defibrillator; Remote monitoring; Ventricular arrhythmia; β-Blockers.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Arrhythmias, Cardiac / therapy
  • Cardiac Resynchronization Therapy* / adverse effects
  • Defibrillators, Implantable* / adverse effects
  • Heart Failure* / complications
  • Heart Failure* / diagnosis
  • Heart Failure* / therapy
  • Heart Rate
  • Humans
  • Middle Aged
  • Prognosis
  • Risk Factors
  • Stroke Volume
  • Tachycardia, Ventricular* / etiology
  • Tachycardia, Ventricular* / therapy
  • Ventricular Dysfunction, Left* / complications
  • Ventricular Fibrillation / therapy