Serial assay of plasma atrial natriuretic peptide （ANP） levels in patients with acute myocardial infarction

To evaluate plasma levels of immunoreactive atrial natriuretic peptide in patients with acute myocardial infartion（AMI）, we studied 23 patients and 16 normal subjects. The results showed that the average plasma ANP levels in patients with AMT was more higher than that in normal subjects (544.36±90.81 pg/ml and 293.88±39.94pg/ml, respectively, P＜（0.05）. Following myocardial infarction, plasma ANP levels rose, having two peaks each in the first and the seventh day. When the extensive anterior wall or two walls of left vetricle were involved, the plasma ANP was 575.78±78.51pg/ml, which was much higher than that in normal subjects （P＜0.01）. The average plasma ANP concentrations were different in patients with various types of AMI, being 547.92±112.52pg/ml in KILLIP class Ⅰ, Ⅱ and 577.55±121.44pg/ml in KILLIP class Ⅲ. It was significantly higher in class Ⅰ—Ⅲ than in normal subjects （P＜0.05 and P＜0.01, respectively）. Finally, the mechanism and the clinical significance of the change in plasma ANP levels in patients with AMI was briefly discussed.