Association of resting heart rate changes over one year with clinical outcomes in heart failure: A multicenter prospective observational study

Background Resting heart rate (RHR) is a well-established prognostic marker in patients with heart failure (HF), with higher RHR associated with increased mortality and hospitalization rates1. Elevated RHR reflects increased sympathetic activity and impaired autonomic regulation, both of which result in adverse cardiovascular outcomes. While baseline RHR has been extensively studied, limited data are available regarding the prognostic implications of temporal changes in RHR (ΔRHR) in patients with chronic HF (CHF)2. Purpose We examined the association between ΔRHR (change in RHR over one year) and cardiovascular events in patients with CHF. Methods We analyzed 3,412 patients with CHF (male 2,369 (69%)/ female 1,043 (31%), mean age 67.9 years) enrolled in our multicenter, prospective CHART-2 (Chronic Heart Failure Analysis and Registry in the Tohoku District-2) Study. Time-dependent Cox regression was used to assess the relationship between ΔRHR and the composite outcome of cardiovascular death and HF hospitalization, stratified by cardiac rhythm (sinus rhythm [SR] vs. atrial fibrillation [AF]) and left ventricular ejection fraction (LVEF). Results Higher ΔRHR was consistently associated with increased risk of adverse cardiovascular outcomes across the overall cohort. After adjusting for baseline RHR and potential confounders, each 10 bpm increase in ΔRHR was significantly associated with an elevated risk of the composite outcome (adjusted hazard ratio [HR] 1.08, 95% confidence interval [CI] 1.04–1.13, P = 0.0002) (Figure). This association was particularly pronounced in patients with sinus rhythm (n=2,118; HR 1.13, CI 1.05–1.22, P = 0.0016), with the strongest relationship observed in those with SR and LVEF ≤50% (n=429; HR 1.23, CI 1.08–1.40, P = 0.0017). In contrast, the association was not significant in patients with SR and LVEF >50% (n=1,080; HR 1.10, CI 0.97–1.24, P = 0.13). In contrast, among those with atrial fibrillation, a significant association was found in patients with LVEF >50% (n=745; HR 1.10, CI 1.02–1.18, P = 0.0089), whereas no significant association was noted in those with LVEF ≤50% (n=204; HR 0.90, CI 0.80–1.02, P = 0.10). Conclusions Changes in RHR over one year were significantly associated with prognosis in patients with CHF, independent of baseline RHR. The strength of this association was particularly notable in patients with sinus rhythm and reduced LVEF, highlighting the clinical relevance of monitoring ΔRHR in HF management, especially when stratifying by LVEF and cardiac rhythm.