103 - Correlation of serum N-terminal pro-B-type natriuretic peptide with conventional and tissue Doppler imaging echocardiographic parameters in patients with transient tachypnea of the newborn.

Poster Number: 103
Publication Number: 103.2284

Background: Transient tachypnea of the newborn (TTN) is a consequence of inadequate neonatal lung fluid clearance. Heart and lungs are highly functionally related and are tightly interdependent. However, cardiac function in TTN was less evaluated and relationship between serum N-terminal pro-B-type natriuretic peptide (NT-proBNP) and cardiac function in TTN was still unknown.

Objective: The aim of the study was to investigate correlations between serum NT-proBNP level and conventional and tissue Doppler imaging (TDI) echocardiographic parameters in TTN.

Design/Methods: A retrospective study involving 70 infants with TTN and 10 controls ≥ 34 weeks gestational age was conducted between December 2019 and July 2023. In TTN group, < 33 weeks gestational age and complicated with congenital heart disease were excluded in this study. Serum NT-proBNP and cardiac functions evaluated by echocardiography were measured on admission (at birth or first day of life). Biventricular systolic, diastolic and global function were measured by conventional and TDI echocardiography. We measured right ventricular (RV) systolic (S) and left ventricular (LV) diastolic (D) duration using tricuspid regurgitation and transmitral flow from Doppler flow, to calculate the S:D ratio as a novel index of global ventricular interaction. We investigated correlation between NT-proBNP level and echocardiographic parameters in TTN by using univariate and multivariate logistic regression analysis.

Results: There was no significant difference in NT-proBNP level between TTN group and control group (control group: 2569pg/ml±1654, TTN group: 3405±5673pg/ml, p=0.35). In TTN group, NT-proBNP level was significantly correlated with LV deceleration time (DT) (r=-0.3, p< 0.05), LV myocardial performance index (MPI) (r=0.27, p< 0.05), the S:D ratio (r=0.35, p< 0.01) and RV MPI (r=0.33, p< 0.01). There were no correlations between NT-proBNP and all TDI echocardiographic parameters. In multivariate logistic regression analysis, RV MPI was independent factor associated with NT-proBNP in TTN group (regression coefficient: 9516, 95% CI: 1355-17677, p< 0.05).

Conclusion(s): Serum NT-proBNP in TTN group was associated with global biventricular dysfunction such as biventricular MPI and the S:D ratio, but not TDI echocardiographic parameters which indicated regional function. Global echocardiographic parameters, especially RV MPI, is an important indicator of cardiac condition in patients with TTN.