Increased endothelin-1 production in patients with chronic heart failure

Abstract

Endothelin-1 (ET-1) concentrations are elevated in patients with congestive heart failure (CHF), although the cause of this increase remains uncertain. We hypothesized that abnormalities in ET-1 production, clearance, or a combination of these may be the cause of elevated ET-1 concentrations in chronic CHF. The kinetics of clearance of ET-1 were measured with ¹²⁵I-labeled ET-1 in eight patients with CHF and five age-matched normal individuals. In both normal subjects and the CHF group, the kinetics of ET-1 clearance were best described by a three-compartment model. The steady-state volume of distribution of ET-1 was significantly greater in the CHF group compared with normal subjects (25.2 ± 3.9 vs. 13.8 ± 2.1 l/kg; P < 0.05). The total clearance rate from plasma was greater in the CHF group (0.119 ± 0.018 vs. 0.047 ± 0.013 l·kg^–1·min^–1; P = 0.05). The total body production rate of ET-1 was also significantly higher in patients with CHF (0.21 ± 0.03. vs. 0.06 ± 0.02 ng·kg^–1·min^–1; P < 0.05). It appears that increased ET-1 production rather than decreased clearance is the cause of elevated ET-1 concentrations in patients with chronic CHF.