Endothelial Function: A Novel Marker to Evaluate the Prognosis of Heart Failure with Reduced Ejection Fraction

Abstract

Background Endothelial function, a key determinant of prognosis in heart failure with reduced ejection fraction (HFrEF), is still frequently under-assessed in clinical practice. The present study aimed to assess endothelial function in patients with HFrEF and investigate its association with echocardiography and hemodynamics over 3 months of medical treatment. Additionally, this study aimed to investigate the association between changes in endothelial function and the incidence of cardiovascular rehospitalizations or deaths. Methods This prospective longitudinal study included 120 patients with HFrEF. Hemodynamic parameters were assessed using impedance cardiography. Endothelial function was evaluated using digital thermal monitoring to calculate the Endothelial Quality Index (EQI) at baseline and after 3 months. Patients were followed for 12 months. Results The mean age was 61.9 ± 10.2 years, with a sex ratio of 5:1. 42.5% of patients tend to experience endothelial dysfunction at baseline. After 3 months of optimal medical therapy (i.e., renin-angiotensin35 aldosterone system inhibitors, beta-blockers, the aldosterone antagonist spironolactone, and sodium- glucose co-transporter 2 inhibitors), EQI improved significantly (p<0.001), correlating with improved echography and hemodynamic parameters. Over 12 months, there were 5 deaths (4.16%) and 44 heart failure rehospitalizations (36.6%), predominantly among those with severe endothelial dysfunction (p=0.008). Improved EQI was associated with reduced mortality (AUC = 0.82) and rehospitalization risk (AUC = 0.837). A ΔEQI ≥ 0.2 predicted a better prognosis (HR: 0.157, 95% CI: 0.054-0.454, p=0.001). Conclusion Patients with HFrEF exhibited endothelial dysfunction. The improvement in endothelial function after an optimized treatment is associated with an enhancement in echography and hemodynamic parameters. Additionally, endothelial function was a strong prognostic marker.

Keywords: Chronic heart failure; echography; endothelial function; impedance cardiography; prognosis.