Plasma nitric oxide products correlate with cardiac index of congenital heart disease.

We wished to determine the relationship between circulating levels of nitric oxide (NO) and cardiac index (CI) in children with congenital heart diseases. We measured the plasma levels of nitrate/nitrite (NO(x)), the stable end products of NO production as well as tumor necrosis factor-alpha (TNF-alpha), atrial natriuretic peptide (ANP), and brain natriuretic peptide in relation to various parameters determined simultaneously. The plasma NO(x) levels correlated negatively with CI (r = -0.541, p < 0.05). No correlation was observed between NO(x) and cardiac output. TNF-alpha correlated with NO(x) levels (r = 0.593, p < 0.005) but not with either CI or cardiac output. Plasma levels of ANP and TNF-alpha were higher in atrial septal defect than those in the control group (p < 0.001 and p < 0.05, respectively). Elevated plasma NO(x) could explain the increased basal release of endothelial NO due to high pulmonary blood flow. Plasma NO(x) correlate negatively with CI in young patients with left-to-right shunt congenital heart diseases.