Background: Atrial septal defect (ASD) accounts for 10% of all congenital heart lesions and represent the third most congenital cardiac defect seen in adults. Atrial natriuretic peptide (ANP) is an important regulator of the sodium and volume homeostasis. This study was designed to investigate the changes in plasma ANP concentrations and three-dimensional echocardiography (3DE) measurements of cardiac volume in patients with ASD during transcatheter closure of defect.
Methods: Plasma ANP concentrations and transthoracic 3DE measurements of right ventricular volume were performed in 46 patients with ASD before closure, and at 3 days after closure. 22 healthy subjects matched for age, sex served as control subjects.
Results: The 46 patients (20 men, 26 women; mean age 26.32 +/- 13.28, range 6 to 63 years) were diagnosed to secundum ASD (the stretched diameters of ASD were from 9~36(25.34 +/- 7.80 mm), and had been successfully placed Amplatzer septal occluder (the sizes of occluder were from 11 to 40 mm). The results showed that compared with control subjects, plasma ANP concentrations were elevated in patients with ASD. Plasma ANP concentrations positively correlated significantly with pulmonary artery pressure (PAP) (r = 0.74, p < 0.05) and 3DE measurements of cardiac volumes (right ventricular end-diastolic (r = 0.50, p < 0.05) and end-systolic volume (r = 0.50, p < 0.05) and negatively correlated with RVEF (r = -0.38, p < 0.05). Transthoracic 3DE measurements of right ventricular volume and plasma ANP concentrations decreased significantly at 3 days after closure (p < 0.05) compared with it before closure.
Conclusion: Plasma ANP concentrations were markedly elevated in patients with pulmonary arterial hypertension and right ventricular volume overload and decreased significantly after closure of ASD. This study suggested that ANP may help to identify patients with ASD complicated by pulmonary arterial hypertension and right ventricular volume overload that demanded early intervention and may become effective marker for evaluating changes in cardiac load after transcatheter ASD closure.