Plasma immunoreactive endothelin in the acute and subacute phases of myocardial infarction in patients undergoing fibrinolysis.

Endothelin is a potent vasoconstrictor of coronary arteries. We measured plasma concentrations of immunoreactive endothelin (irET) in 46 patients with confirmed acute myocardial infarction (AMI). When compared with irET concentrations in healthy individuals who served as controls, irET concentrations in patients were already significantly elevated at the time of admission (P = 0.002) and remained significantly elevated for at least 2 days after AMI (P < 0.01). IrET concentrations peaked 1 h (mean) after admission (8.5 +/- 3.9 ng/L, P = 0.02 compared with values at time of admission). Reperfusion of the infarct-related artery markedly influenced irET release. Before the start of thrombolytic therapy, irET concentration in patients with early reperfusion did not differ significantly from that of those without early reperfusion. However, irET time courses were significantly (P = 0.03 by analysis of variance) different in patients who did and did not have early reperfusion. In the latter, peak irET concentrations correlated closely with the angiographic left ventricular ejection fraction (r = -0.71, P = 0.03), maximum creatine kinase MB mass concentrations (r = 0.69, P = 0.01), and creatine kinase activities (r = 0.59, P = 0.03). Reflow and reversion of myocardial ischemia are associated with a reduced irET release in patients with AMI.