Achieved targeted heart rate following ivabradine therapy correlates with left ventricular reverse remodeling in non-ischemic dilated cardiomyopathy

The effect of ivabradine on left ventricular reverse remodeling (LVRR) in heart failure with reduced ejection fraction and its correlation with achieved heart rate (HR) by ivabradine in non-ischemic dilated cardiomyopathy (NIDCM) remain uncertain. A retrospective analysis of 255 sinus rhythm NIDCM patients at a tertiary center (2012-2021) were categorized into four groups based on the ivabradine use (Iva+/-) and achieved HR at 1-year (HR+/-). The HR cut-off of 70 bpm was determined via receiver operating characteristic curve analysis for LVRR, defined as an absolute ≥ 10% improvement in LV ejection fraction (LVEF) from baseline, with a final LVEF ≥ 40%. LVRR incidence at 1-year was, 46.8% in Iva-/HR70+, 46.6% in Iva-/HR70-, 62.9% Iva+/HR70+ and 71.1% in Iva+/HR70-. Ivabradine treated patients with HR < 70 bpm had higher incidence of LVRR than those without ivabradine (Iva+/HR70-vs. Iva-/HR70+, OR 4.85, 95%CI 1.97-11.96 P = 0.001; Iva+/HR70-vs. Iva-/HR70-, OR 3.60, 95% CI 1.41-9.18, P = 0.007) after adjustment for known predictors in a multivariate model. Consistent adherence to beta-blockers and ivabradine, along with guideline-directed medical therapy (GDMT) for HF, and sex were identified as independent predictors of LVRR. Ivabradine therapy achieving HR < 70 bpm correlated with increased LVRR incidence in NIDCM patients, underscoring the role of ivabradine in HR reduction adjunctive to GDMT.