INCREASED PLASMA ADRENOMEDULLIN IN ACUTE MYOCARDIAL-INFARCTION

Adrenomedullin has a potent vasodilating effect comparable to that of calcitonin gene-related peptide. To investigate the pathophysiologic r ole of endogenous adrenomedullin, we determined sequentially the plasm a adrenomedullin level in 15 consecutive patients with acute myocardia l infarction (AMI). Plasma adrenomedullin was higher immediately after the onset of AMI and decreased gradually; plasma levels during the 3- week period after the AMI were higher than plasma levels in 15 healthy control subjects (p < 0.001), with higher levels in patients with con gestive heart failure than in patients without congestive heart failur e throughout the period of the study (p < 0.05). Plasma adrenomedullin was positively correlated with pulmonary capillary wedge pressure, pu lmonary arterial pressure, right atrial pressure, and heart rate in th e early stage of AMI. These findings suggest that the elevation of pla sma adrenomedullin is related to the retention of body fluid volume, t he enhancement of sympathetic activity, and/or the elevation of pressu re in pulmonary vascular beds. Adrenomedullin may act against excessiv e vasoconstriclors increased in AMI.