NT-proBNP is associated with different diseases of prematurity; increased NT-proBNP and BNP levels have been found in infants with hemodynamically significant patent ductus arteriosus (hsPDA) [6–9], bronchopulmonary dysplasia (BPD) [10–15], pulmonary hypertension (PH) [16–22], retinopathy of prematurity (ROP) [23, 24], inflammation or sepsis [25–27], and congenital heart diseases [28, 29], but published data remain inconclusive. This evidence concerns the gene NPPB and pulmonary arterial hypertension.