Interdependence of cardiac and endothelial function in patients with symptomatic chronic heart failure of nonischemic etiology

Objective: Endothelial dysfunction has emerged as a therapeutic target in patients with chronic congestive heart failure (CHF). Endothelial dysfunction may impair left ventricular (LV) systolic function by increasing systemic vascular resistance. Conversely, LV impairment may negatively impact endothelial function by reducing shear stress and vascular nitric oxide (NO) bioavailability. This study was undertaken to determine the association between LV and endothelial function in patients with CHF. Methods: Echocardiographic and vascular ultrasound studies were performed to measure left ventricular ejection fraction (LVEF) and brachial artery flow-mediated vasodilatation (FMD) in 30 subjects with stable New York Heart Association class II-III CHF. All patients received optimal medical therapy. Results: LVEF averaged 25 ± 9% and brachial artery FMD 1.3 ± 2.4%. LVEF strongly correlated with FMD among all patients (r = 0.64, P< 0.001) and among those patients with nonischemic (n = 19, r = 0.66, P = 0.002), but not in patients with ischemic etiology (n = 11, r = 0.27, P = 0.42). Conclusions: LVEF and endothelium-dependent NO vasodilatation are strongly correlated in stable ambulatory patients with systolic CHF of nonischemic etiology. Our study underscores the mutual interaction between central cardiac and peripheral vascular function, thus strengthening a mechanistic rationale for the systemic beneficial effects of interventions targeting either the heart or the vascular endothelium in CHF.