Interventional catheterization decreases plasma levels of atrial natriuretic peptide (ANP) in children with congenital heart defects

Atrial natriuretic peptide (ANP) is one of the cardiac peptides implicated in volume and sodium homeostasis. We investigated the effect of interventional catheterization on plasma levels of ANP, aldosterone, and cortisol in 28 children with various congenital heart defects (CHD). Patients were divided by age into two groups: group A - infants and children over 3 months of age (n = 22), and group B - newborns (n = 6). These were compared to age-matched control groups. In group A, interventions included pulmonic valvotomy (n = 8), aortic valvotomy (n = 4), balloon angioplasty of native coarctation of the aorta (n = 3), balloon dilatation of the mitral valve (n = 1), and Rashkind double umbrella closure of patent ductus arteriosus (n = 6). Group B interventions included pulmonic valvotomy (n = 3), aortic valvotomy (n = 1), and balloon atrial septosomy (n = 2). In group A, mean ANP levels were markedly higher than in age-matched controls (125.2 ± 15.8 vs. 24.6 ± 4.6 pg/ml) (P <0.0001), and decreased immediately after intervention (75.6 ± 11.4 pg/ml, P <0.02), and more markedly on follow-up (42.9 ± 5.0 pg/ml, P <0.0001). In group B (newborns), mean basal plasma levels were high before and after intervention and were not different from age-matched controls (243 ± 42.1 vs. 220.8 ± 16.2 pg/ml). There was a significant decrease on follow- up measurement (62.1 ± 12.7 pg/ml, P <0.005). In both groups, plasma cortisol levels increased significantly immediately following catheterization (P < 0.02), and normalized on follow-up. Basal aldosterone levels were normal in group A and high in Group B (9.9 ± 3.8 vs. 167.6 ± 16.9 ng/dl) (P < 0.001). It is suggested that plasma ANP levels are increased in children with CHD, without overt heart failure, and decrease significantly following successful intervention. In newborns with CHD, the physiological high ANP levels obscure the effect of the CHD.