Relationship between plasma atrial natriuretic polypeptide concentration and hemodynamic measurements in children with congenital heart diseases.

The plasma alpha-atrial natriuretic polypeptide (alpha-ANP) concentration in the peripheral veins of children with congenital heart diseases was measured by radioimmunoassay and compared with cardiac catheterization data. Every patient with heart failure had a higher alpha-ANP concentration (132.1 to 858.7 pg/mL) than the upper limit of the normal range (11.7 to 98.7 pg/mL), whereas more than half of the patients without heart failure had a normal alpha-ANP concentration. Although none of the 13 children with atrial septal defect had heart failure, their mean (+/- SD) plasma alpha-ANP concentration (99.4 +/- 40.7 pg/mL) was significantly higher than that in control children (44.6 +/- 22.3 pg/mL). The plasma alpha-ANP concentration was significantly correlated with the pulmonary blood flow/systemic blood flow (Qp/Qs) ratio in the children with atrial septal defect. In the 34 children with ventricular septal defect the plasma alpha-ANP concentration increased in relation to increasing size of the defect. The plasma alpha-ANP concentration was significantly correlated with the Qp/Qs ratio, pulmonary artery pressure, and left atrial pressure, estimated from mean pulmonary artery wedge pressure, in the children with ventricular septal defect. In the children with tetralogy of Fallot, the mean plasma alpha-ANP concentration was normal, and mean right and left atrial pressures were not increased. The elevated alpha-ANP concentration in the three patients with heart failure decreased after their conditions improved with various treatments. Thus the measurement of alpha-ANP concentration may be valuable in evaluating the presence or absence of heart failure and the response to treatment in children with congenital heart diseases. Distention of the right and left atrial might induce the release of alpha-ANP in patients with atrial and ventricular septal defects, respectively.