Effective renal plasma flow response and atrial natriuretic peptide in patients with uncomplicated acute myocardial infarction.

Effective renal plasma flow was determined by using I-131 labeled iodo-ortho-hippurate in 17 Chinese patients admitted to the coronary care unit with uncomplicated acute myocardial infarction. The first determination, immediately after admission, was significantly higher than the second determination done a week later, 444.5 +/- 153.9 vs. 371.1 +/- 124.9 ml/min (p < 0.02). The initial rise of effective renal plasma flow (ERPF) after acute myocardial infarction seemed to be correlated to the initial elevation of atrial natriuretic peptide (ANP), which was determined sequentially 6 times in each patient (91.3 +/- 39.4, 25.6 +/- 9.7, 37.4 +/- 12.3, 51.8 +/- 18.2, 65.6 +/- 20.8, 57.4 +/- 19.2 pg/ml, respectively). It was concluded that, in the presence of uncomplicated acute myocardial infarction, patients may show renal vasodilatation, and that the elevation of ANP may play some role in this.