Background: Heart diseases are currently a significant cause of morbidity and mortality in newborns. The existing diagnostic methods are often not sufficient or, in many cases, cannot be used. Great advances have been achieved in medical knowledge concerning biomarkers for the diagnosis of circulatory system disorders in adult patients. Among these biomarkers, N-terminal pro-brain type natriuretic peptide (NT-proBNP) plays a main role. However, in the existing literature, there is not enough data concerning the physiological features of this biomarker in newborns and its potential use in neonatal cardiac diagnostics.
Objectives: To evaluate the diagnostic usefulness of NT-proBNP measurements in correlation with other markers of circulatory failure and myocardial damage in newborns with heart defects.
Material and methods: This study involved 126 newborns. Patients were divided into 2 main groups: group I included infants with congenital heart defects (CHD) and group II (control) included healthy neonates. Newborns with CHD were further divided into 2 subgroups: group Ia with simple shunts and group Ib with combined heart defects. Patients in group I were further divided according to the hemodynamic significance of CHD. The NT-proBNP level was evaluated using the CARDIAC proBNP immunologic test (Cobas h232; Roche Diagnostics, Basel, Switzerland).
Results: The NT-proBNP concentrations were significantly higher in newborns with CHD compared to healthy ones. Newborns with combined heart defects had higher levels of NT-proBNP than newborns with simple shunts. The NT-proBNP concentrations in newborns with CHD correlated with echocardiographic parameters of hemodynamic significance and with left ventricular ejection fraction (LVEF). Additionally, NT-proBNP correlated with clinical symptoms of heart failure (HF; Ross classification, Reithmann's score).
Conclusions: Statistically significant differences in NT-proBNP level between newborns with heart defects and healthy controls were shown. In newborns with heart diseases, significant correlations were found between NT-proBNP level and the type of heart defect (simple shunt or combined defects), the hemodynamic significance of the defect, LVEF, and the clinical intensity of HF.
Keywords: NT-proBNP; biomarkers; congenital heart defects; newborns.