Increased Plasma Concentrations of Endothelin in Congestive Heart Failure in Humans

Congestive heart failure is characterized by decreased cardiac output and increased peripheral vascular resistance. Endothelin, a peptide found in plasma, is a potent vasoconstrictor. We hypothesized that plasma concentrations of endothelin are increased in humans with congestive heart failure. Plasma samples were obtained from 71 healthy control subjects and 56 patients with congestive heart failure. The mean plasma concentration of endothelin, measured by radioimmunoassay, was 7.1 ± 0.1 pg/ml in the 71 normal control subjects but 12.6 ± 0.6 pg/ml in the 56 patients with heart failure (P = 0.001). To evaluate the relationship between circulating endothelin and clinical stage of congestive heart failure, we categorized patients into two groups—those with mild heart failure (New York Heart Association class I or II) and those with severe heart failure (class III or IV). Circulating endothelin in the 24 patients with mild disease was 11.1 ± 0.7 pg/ml, significantly higher than in normal subjects (P