Plasma atrial natriuretic peptide in patients with congenital heart diseases.

The plasma level of human alpha-atrial natriuretic peptide was measured in healthy children and patients, 1 month to 15 years of age, with congenital heart diseases. Significant increases were found in patients with a ventricular septal defect, tricuspid valve atresia, patent ductus arteriosus, and atrial septal defect but not in those with pulmonary valve stenosis or tetralogy of Fallot. The levels were significantly higher in children with ventricular septal defects (221 +/- 123 pg/mL) or patent ductus arteriosus (124 +/- 38 pg/mL) than in those with atrial septal defects (65 +/- 42 pg/mL) (P less than .01). The increased levels appeared to be correlated with enlargement of the left atrium (r = .85, P less than .01) but not with the right atrial size or the mean right atrial pressure. They were higher in younger than in older healthy infants, but this age difference did not affect the results. These findings indicate that human alpha-atrial natriuretic peptide is released into the circulation in response to chronic atrial expansion in patients with congenital heart disease and may have an important role in volume homeostasis.