Effects of ivabradine on endothelial function, aortic properties and ventricular-arterial coupling in chronic systolic heart failure patients.

Abstract

Heart rate (HR) is an important prognostic factor in patients affected by chronic heart failure (CHF); ivabradine has been demonstrated to significantly reduce nonfatal myocardial infarction and hospitalization rate for acute heart failure and to improve left ventricular (LV) reverse remodeling, quality of life, exercise capacity, and arterial elastance (Ea) in these patients. We aimed at evaluating the short-term effects of ivabradine on ventricular-arterial coupling (VAC), aortic stiffness, and endothelial function in stable patients with CHF. We evaluated 30 consecutive CHF patients (LVEF≤ 35%, NYHA class II) with sinus rhythm and HR ≥ 70bpm on optimized pharmacological therapy. All of them underwent both transthoracic echocardiogram to assess aortic elastic properties (aortic distensibility, AD; aortic stiffness index, ASI; systolic aortic strain, SAS) and VAC, and peripheral arterial tonometry to measure endothelial function. Therapy with ivabradine 5mg bid was added and each patient was evaluated with the same examinations after 4months. At the baseline, 73% of patients had impaired VAC and 63% endothelial dysfunction. After 4months, there was a significant improvement in the VAC value (ΔVAC -0.10±0.18, P=.021), mainly linked to Ea (ΔEa -0.40±0.23mm Hg/mL; P=.003). All the parameters of aortic elasticity underwent significant improvement (ΔAD 1.82±1.43cm² × dyn- ¹, P=.004; ΔASI -4.73±6.07, P=.033; ΔSAS -7.98±4.37%, P=.003). Lastly, we also noted a significant improvement of endothelial function (Δ RHI 0.35±0.35; P<.001). At follow-up 40% of patients had impaired VAC (P=.018) and 33% endothelial dysfunction (P=.038). In patients with CHF adding ivabradine on top to the standard optimized medical therapy, when indicated, seems to improve endothelial function, aortic properties, and VAC.