Plasma endothelin-1 levels and clinical correlates in patients with chronic heart failure

Abstract

Background: Endothelin-1 (ET-1) is a potent vasoconstrictor peptide, and patients with chronic heart failure (CHF) are reported to have high plasma ET-1 levels. The aim of this study was to investigate the relation between plasma ET-1 levels and clinical correlates in patients with CHF. The effects of maximal exercise on plasma ET-1 levels were also investigated. Methods: Plasma concentrations of ET-1, norepinephrine, and atrial and brain natriuretic peptide (ANP and BNP) both at rest and after maximal cardiopulmonary exercise test were determined in 100 patients with CHF (60 ± 12 years, New York Heart Association [NYHA] class I-III, left ventricular ejection fraction [LVEF] = 36 ± 8%, peak oxygen uptake [VO2] = 18.2 ± 5.0 mL/min/kg) and 27 controls. Results: Patients with NYHA class II and III CHF had higher ET-1 levels (controls, NYHA class I, II, III: 2.1 ± 0.6, 2.1 ± 1.0, 2.6 ± 0.9, 3.4 ± 0.8 pg/mL, analysis of variance P <.0001). Maximal exercise did not alter ET-1 levels in controls or in each CHF subgroup. When all CHF patients were analyzed together, cardiothoracic ratio (P <.01), peak VO2 (P <.001), plasma norepinephrine (P <.01), plasma ANP (P <.01), and plasma BNP (P <.001) were significantly related with resting ET-1 levels on univariate analysis. Multivariate analysis revealed peak VO2 and plasma BNP levels showed an independent and significant relationship with the resting plasma ET-1 levels. Conclusions: Resting ET-1 levels were increased in symptomatic patients with CHF, and maximal exercise did not increase ET-1 levels. Peak VO2 and plasma BNP levels were independently associated with resting plasma ET-1 levels in patients with CHF.