Before closure, in 46 patients with ASD, the plasma ANP concentrations positively correlated with RVEDV (r = 050; p < 0.05) and RVESV (r = 050; p < 0.05); and it negatively correlated with RVEF (r = -0.38; p < 0.05) (Fig 5). Here, NPPA is linked to atrial septal defect.