238 - Fetal Cardiac Speckle Tracking in Congenital Diaphragmatic Hernia – A Case-Control Study

Publication Number: 4234.238

Alexie Fonta Holder, Universite de Montreal Faculty of Medicine, Montréal, PQ, Canada; Camilo Lopez Ibarra, CHU Sainte-Justine, Université de Montréal, Montreal, PQ, Canada; Amanda Ohayon, Faculty of Medicine Université Laval, Montreal, PQ, Canada; Sam Amar, McGill University Faculty of Medicine and Health Sciences, Montreal, PQ, Canada; Sariya Sahussarungsi, Thammasat University, Khlong Luang, Pathum Thani, Thailand; Phoenix Plessas-Azurduy, McGill University Faculty of Medicine and Health Sciences, Montreal, PQ, Canada; Daniela Villegas Martinez, McGill University Faculty of Medicine and Health Sciences, Montreal, PQ, Canada; Mona Beaunoyer, Universite de Montreal Faculty of Medicine, Montreal, PQ, Canada; Pramod Puligandla, McGill University Faculty of Medicine and Health Sciences, Montreal, PQ, Canada; Marie-Josée Raboisson, Sainte Justine University Hospital Centre, Montreal, PQ, Canada; Tiscar Cavalle-Garrido, McGill University Faculty of Medicine and Health Sciences, Montreal, PQ, Canada; Anie Lapointe, Universite de Montreal Faculty of Medicine, Montreal, PQ, Canada; Gabriel Altit, McGill University Faculty of Medicine and Health Sciences, Montreal, PQ, Canada

Background: In congenital diaphragmatic hernia (CDH), the highest-risk infants often present decreased left ventricular (LV) dimensions, which is associated to extracorporeal membrane oxygenation (ECMO) use and mortality. Postnatally, a small LV may reflect true hypoplasia, reduced preload, and/or compression from a pressure-loaded right ventricle. Fetal assessment provides an opportunity to distinguish intrinsic LV hypoplasia from secondary adaptations when compared with normal fetuses.

Objective: To evaluate cardiac parameters in fetuses with CDH using speckle-tracking echocardiography (STE) from apical four-chamber views, and to compare them with gestational age (GA)-matched controls from uncomplicated pregnancies with normal fetal echocardiography.

Design/Methods: We conducted a retrospective, multicenter case-control study including fetuses with prenatally diagnosed CDH and live birth between 2014-2024. Exclusion criteria were preterm birth < 34 weeks, bilateral CDH, and major anomalies. Controls were selected from uncomplicated pregnancies referred for fetal echocardiography due to family history of congenital heart disease or inconclusive routine obstetrical scans, all with a structurally normal heart. Fetal echocardiography was performed between 20 and 32 weeks' GA. Clinical and prenatal data were extracted from patient charts (Table 1). For each case, the first available fetal echocardiogram was reviewed, and the apical four-chamber view was analyzed by STE (TomTec). Two controls were matched to each CDH case.

Results: Ninety-six fetuses were included: 39 (41%) with CDH and 57 (59%) controls - characteristics in Table 1. GA at fetal ECHO was similar between groups (Table 2). Compared with controls, fetuses with CDH had significantly greater RV fractional area change (41% vs 37%, p=0.02). RV free-wall strain (-25.3% vs -18.0%, p< 0.001) and strain rate (-1.9 s⁻¹ vs -0.9 s⁻¹, p< 0.001) were also increased in CDH. CDH fetuses exhibited smaller LV end-diastolic volume (0.45 ml vs 0.86 ml, p< 0.001). LV longitudinal strain (-25.0% vs -20.3%, p< 0.001) and strain rate (-1.8 s⁻¹ vs -1.1 s⁻¹, p< 0.001) were significantly higher, suggesting a compensatory response to reduced LV volume and stroke output (Figure 1).

Conclusion(s): Fetuses with CDH show distinct alterations in cardiac mechanics, characterized by reduced LV filling volumes and hyperdynamic biventricular strain responses. Fetal STE may provide early markers of altered LV dimensions in CDH, aiding in the identification of fetuses at higher risk and refining risk stratification. Future studies should validate these findings in other larger prospective cohorts.

Table 1: Demographics and Clinical Characteristics of Cohort
Data are presented as mean (standard deviation) or median (interquartile range), depending on the distribution, as well as count (percentage).  

Abbreviations: CDH (Congenital Diaphragmatic Hernia); GA (Gestational Age); SD (Standard Deviation); FETO (Fetal Endoluminal Tracheal Occlusion).

Table 2: Ventricular Deformations and Dimensions by Speckle-Tracking Echocardiography
Data are presented as mean (standard deviation) or median (interquartile range), depending on the distribution, as well as count (percentage).

Abbreviations: CDH (Congenital Diaphragmatic Hernia); EF (Ejection Fraction); EDV (End Diastolic Volume); ECHO (Echocardiography); GA (Gestational Age); GLS (Global Longitudinal Strain); LV (Left Ventricle); RV (Right Ventricle); SD (Standard Deviation)

Figure 1: Right and Left Ventricular Strain Rates