Increased plasma adrenomedullin levels in chronic congestive heart failure

Adrenomedullin is a potent vasodilator peptide and occurs in circulating blood of human beings and experimental animals. Because it is produced in intact aorta of rats and in cultured vascular endothelial cells, adrenomedullin seems to participate in regulation of local vascular tone. To determine the pathophysiological roles of adrenomedullin, we investigated its plasma concentrations in 49 patients with heart failure. Plasma adrenomedullin levels increased significantly with advancing severity of the disease (New York Heart Association functional class I, 4.1 +/- 1.0; II, 5.6 +/- 1.6; III, 6.4 +/- 0.8; IV, 13.2 +/- 6.8 (fmol/l). Plasma adrenomedullin was correlated with pulmonary artery pressure (r = 0.44, p = 0.0114) and pulmonary capillary wedge pressure (r = 0.53, p = 0.0002). These findings indicate that adrenomedullin may play some important role in the pathophysiologic makeup of heart failure by its vasodilating effects against the concomitant exaggeration of humor pressor agents such as catecholamine and the renin-angiotensin system. Hemodynamic changes in pulmonary circulation may have some influence on the increased synthesis and secretion of plasma adrenomedullin in chronic congestive heart failure.