INCREASED PLASMA ADRENOMEDULLIN LEVELS IN PATIENTS WITH ACUTE MYOCARDIAL-INFARCTION IN PROPORTION TO THE CLINICAL SEVERITY

Objectives-To investigate the pathophysiological role of adrenomedulli n in myocardial infarction. Patients and design-Plasma concentrations of adrenomedullin, atrial natriuretic factor, and brain natriuretic pe ptide were measured by radioimmunoassay in 31 patients with acute myoc ardial infarction over four weeks, and in 44 normal subjects. Results- In patients with acute myocardial infarction, plasma adrenomedullin re ached a peak of (mean (SD) 14.0 (9.0) pmol/l at 24 hours after the ons et of symptoms and remained increased at all sampling points except th e four week point compared with the value in normal subjects (5.0 (2.0 ) pmol/l). Adrenomedullin concentrations on admission were higher in p atients from Killip class II, III, and IV than class I, and correlated positively with peak plasma creatine kinase and left ventricular end diastolic volume index, and negatively with left ventricular ejection fraction. The values from 12 to 48 hours were negatively correlated wi th systemic vascular resistance index. During the time course studied, adrenomedullin concentrations were positively correlated with atrial natriuretic factor (r = 0.40, p < 0.001) and brain natriuretic peptide (r = 0.53, p < 0.001). Conclusions-Plasma adrenomedullin concentratio ns increased in the acute phase of myocardial infarction in proportion with clinical severity, suggesting that adrenomedullin may play an im portant role in the pathophysiology of myocardial infarction.