NPPB and Patent ductus arteriosus: *absolute frequency. Result are shown as median (min-max), P value is assessed by Mann-Whitney (gender) or Kruskal-Wallis test. TNA - transient neurological abnormalities. NT-proBNP - N-terminal pro b-type natriuretic peptide. hs-TnI - high sensitivity troponin I. CK - creatine kinase. CK-MB - creatine kinase-myocardial band. FO - foramen ovale. PDA - patent ductus arteriousus.