Quantitative evaluation of the changes in plasma concentrations of cardiac natriuretic peptide before and after transcatheter closure of atrial septal defect

The purpose of this study was to investigate the changes in plasma concentrations of atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) in patients with atrial septal defect (ASD) during transcatheter closure of defects. The plasma concentrations of ANP and BNP were obtained from 14 patients with ASD at before closure, and at 5 min, 24 h, 1 mo and 3 mo after transcatheter ASD closure using an Amplatzer septal occluder. Ten healthy children aged 6-18 y were studied as controls. All ASDs were successfully closed. Compared with control values (mean ± SD, 17 ± 6.8 ng l^-1), ANP concentrations before closure were significantly elevated (24 ± 9.8 ng l^-1, p < 0.05). ANP concentrations increased significantly at 5 min after closure (34 ± 18 ng l^-1, p < 0.05) compared with preclosure concentrations. At 24 h after closure, the concentrations decreased to values not different from control values (19 ± 11 ng l^-1, p = ns). BNP levels before closure (19 ± 9.9 ng l^-1) were also elevated significantly compared with control values (12 ± 4.9 ng l^-1, p < 0.05). BNP concentrations increased significantly at 5 min after closure (23 ± 14 ng l^-1, p < 0.05) compared with preclosure concentrations. ANP values at 24 h were lower than at 5 min after closure, whereas BNP values were higher (32 ± 11 ng l^-1, p < 0.05). As with ANP, the concentrations gradually decreased to values not different from control values at 3 mo after the procedure (12 ± 6.3 ng l^-1, p = ns). Conclusion: Plasma concentrations of ANP and BNP may become effective markers for evaluating changes in cardiac load after transcatheter ASD closure.