NPPB and bronchopulmonary dysplasia: We could demonstrate significantly higher NT-proBNP values in infants with hsPDA (first week of life, p = 0.034), BPD (first week of life, p = 0.021; 4 ± 1 weeks of life, p < 0.001), PH (4 ± 1 weeks of life, p < 0.001), ROP stage 2 with plus disease or higher (4 ± 1 weeks of life, p = 0.007), infection (first week of life, p = 0.02, 4 ± 1 weeks of life, p = 0.032), IVH grade 2 or higher (first week of life, p = 0.014; 4 ± 1 weeks of life, p = 0.001), and intestinal complications like NEC, FIP, or gastric perforation (first week of life, p = 0.029; 4 ± 1 weeks of life, p = 0.007).