TOP 30 - Correlation between Lung Ultrasound Scores and Echocardiographic Markers of Chronic Pulmonary Hypertension in Extremely Preterm Infants

Publication Number: 1790.TOP 30

Meredith Kinoshita, University of Toronto Temerty Faculty of Medicine, Toronto, ON, Canada; Jenna Ibrahim, University of Toronto Temerty Faculty of Medicine, Toronto, ON, Canada; Amish Jain, University of Toronto Temerty Faculty of Medicine, Toronto, ON, Canada; Adel Mohamed, University of Toronto Temerty Faculty of Medicine, Mississauga, ON, Canada

Background: Chronic pulmonary hypertension (cPH) is a serious complication of bronchopulmonary dysplasia (BPD), affecting 20–30% of extremely preterm infants with moderate-to-severe BPD. Its presence is associated with increased mortality and adverse neurodevelopmental outcomes, making early identification of high-risk infants critically important. However, the optimal timing and strategy for cPH surveillance remain uncertain. Echocardiography (ECHO), the current standard for screening, is typically performed later in the course of evolving BPD (after 32 weeks postmenstrual age [PMA]), potentially missing opportunities for earlier detection and intervention. Lung ultrasound (LUS) is a non-invasive bedside tool that quantifies lung disease severity using standardized scoring. Early LUS (within 14 days) predicts the development of BPD, but its role in predicting cPH has not been explored. Given the pathophysiologic relationship between parenchymal lung injury and pulmonary vascular remodeling, we hypothesize that LUS correlates with ECHO markers of cPH and that early LUS may identify infants at risk before overt pulmonary vascular disease develops. This study aims to evaluate whether LUS can improve early risk stratification and guide targeted cPH surveillance in extremely preterm infants.

Objective: To determine the correlation between LUS scores and echocardiographic findings obtained at or after 32 weeks PMA for cPH screening. Secondary objectives are to assess whether early LUS (day 7–14) predicts subsequent cPH and to examine correlations between LUS scores and specific ECHO parameters of pulmonary hypertension.

Design/Methods: This retrospective cohort study included infants born < 28 weeks gestation admitted to the Mount Sinai Hospital NICU (Toronto, Canada) from January 2020-June 2025. Approval was obtained from local research ethics board (REB #1504). Eligible infants had LUS performed early (day 7–14) and/or late (≥32 weeks PMA) and an ECHO obtained at ≥32 weeks for cPH assessment. Infants with major anomalies or structural heart disease (except PDA, ASD, or PFO) were excluded.
LUS was scored using a standardized six-zone protocol (0–18 total). ECHO parameters included pulmonary artery acceleration time (PAAT), tricuspid annular plane systolic excursion (TAPSE), RV ejection time/PAAT ratio and septal flattening consistent with RV pressure overload. Infants were classified as cPH or no cPH based on ECHO findings. Univariate and correlation analyses will compare LUS and ECHO measures and multivariable regression will adjust for gestational age, BPD severity, PDA and respiratory support.