Endothelial function: a novel marker to evaluate the prognosis of heart failure with reduced ejection fraction

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 mo of medical treatment. In addition, this study aimed to investigate the association between changes in endothelial function and the incidence of cardiovascular rehospitalizations or deaths. 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 mo. Patients were followed for 12 mo. The mean age was 61.9 ± 10.2 yr, with a sex ratio of 5:1. A total of 42.5% of patients tend to experience endothelial dysfunction at baseline. After 3 mo of optimal medical therapy (i.e., renin-angiotensin-aldosterone system inhibitors, β-blockers, the aldosterone antagonist spironolactone, and sodium-glucose cotransporter 2 inhibitors), EQI improved significantly (P < 0.001), correlating with improved echocardiographic and hemodynamic parameters. Over 12 mo, 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 [area under the curve (AUC) = 0.82] and rehospitalization risk (AUC = 0.837). A ΔEQI ≥ 0.2 predicted a better prognosis, with a reduced risk of 1-year rehospitalization for acute heart failure.NEW & NOTEWORTHY Endothelial dysfunction is highly prevalent in patients with heart failure, with significant improvements observed after medical optimization. Importantly, changes in endothelial function strongly correlated with echocardiographic and hemodynamic improvements and independently predicted mortality and rehospitalization risk. Notably, an improvement in endothelial function emerged as a valuable prognostic marker.