Plasma endothelin-1 in acute myocardial infarction with heart failure

Endothelin-1 is a potent vasoconstricting substance that may aggravate circulatory dysfunction in acute myocardial infarction. In 59 patients with acute myocardial infarction peripheral venous blood was sampled, and endothelin-1 was measured by radioimmunoassay. Hemodynamic measurements were performed with a flow-directed thermodilution catheter in 16 patients. Plasma endothelin-1 levels in Killip's classes were as follows: group I (no heart failure, n = 25), 1.97 +/- 0.69 pg/ml; group II (heart failure, n = 16), 2.74 +/- 1.02 pg/ml; group III (pulmonary edema, n = 13), 4.54 +/- 1.17 pg/ml; and group IV (cardiogenic shock, n = 5), 8.91 +/- 3.16 pg/ml (normal control group, n = 12: 1.51 +/- 0.39 pg/ml). There were significant correlations between the plasma endothelin-1 level and mean right atrial pressure (r = 0.554; p < 0.05), mean pulmonary artery pressure (r = 0.589; p < 0.02), and cardiac index (r = -0.534; p < 0.05). There were closer correlations between plasma endothelin-1 level and mean pulmonary artery wedge pressure (r = 0.678; p < 0.005) and total pulmonary vascular resistance (r = 0.831; p < 0.001). These results indicate that endothelin-1 is elevated in accordance with cardiac and pulmonary circulatory distress in patients with acute myocardial infarction, which may further aggravate circulatory dysfunction.