The prognostic value of heart rate at discharge in acute decompensation of heart failure with reduced ejection fraction

Abstract

Aims: The effect of elevated heart rate (HR) on morbidity and mortality is evident in chronic stable heart failure; data in this regard in acute decompensated heart failure (ADHF) setting are scarce. In this single-centre study, we sought to address the prognostic value of HR and beta-blocker dosage at discharge on all-cause mortality among patients with heart failure and reduced ejection fraction and ADHF.

Methods and results: In this retrospective observational study, 2945 patients were admitted for the first time with the primary diagnosis of ADHF between January 2008 and February 2018. Patients were divided by resting HR at discharge into three groups (HR < 70 b.p.m., HR 70-90 b.p.m., and HR > 90 b.p.m.). Evidence-based beta-blockers were defined as metoprolol, bisoprolol, and carvedilol. The doses of prescribed beta-blockers were calculated into a percentage target dose of each beta-blocker and divided to four quartiles: 0 < Dose ≤ 25%, 25% < Dose ≤ 50%, 50% < Dose ≤ 75%, and >75% of the target dose. Cox regression was used to calculate the hazard ratio for various HR categories and adjusting for clinical and laboratory variables. At discharge, 1226 patients had an HR < 70 b.p.m., 1347 patients had an HR at range 70-90 b.p.m., and 372 patients with an HR > 90 b.p.m. The 30 day mortality rate was 2.2%, 3.7%, and 12.1% (P < 0.001), respectively. Concordantly, 1 year mortality rate was 14.6%, 16.7%, and 30.4% (P < 0.001) among patients with HR < 70 b.p.m., HR 70-90 b.p.m., and HR > 90 b.p.m., respectively. The adjusted hazard ratio was significantly increased only in HR above 90 b.p.m. category (hazard ratio, 2.318; 95% confidence interval, 1.794-2.996).

Conclusions: Patients with ADHF and an HR of <90 b.p.m. at discharge had significantly a lower 1 year mortality independent of the dosage of beta-blocker at discharge. It is conceivable to discharge these patients with lower HR.

Keywords: Acute decompensated heart failure; Beta-blockers; Discharge; Heart rate.