108 - Impact of Postnatal Dexamethasone on Right Heart Performance in Premature Neonates

Monday, May 1, 2023

9:30 AM – 11:30 AM ET

Poster Number: 108
Publication Number: 108.426

Jejelola Ladele, University of Toronto Temerty Faculty of Medicine, Toronto, ON, Canada; Talal Altamimi, Imam Abdulrahman Bin Faisal University, Dammam, Ash Sharqiyah, Saudi Arabia; Ayman Saker, Children's Hospital of Eastern Ontario, Ottawa, ON, Canada; Renjini Lalitha, The University of Western Ontario - Schulich School of Medicine & Dentistry, London, ON, Canada; Soume Bhattacharya, The University of Western Ontario - Schulich School of Medicine & Dentistry, London, ON, Canada

Presenting Author(s)

Jejelola Ladele, MBCh.B, FMCPaed

Staff Neonatologist, Assistant Professor
University of Toronto Temerty Faculty of Medicine
Toronto, Ontario, Canada

Background: Use of postnatal Dexamethasone in prevention and treatment of chronic lung disease (CLD) in premature neonates is well established. While studies have documented the effect of Dexamethasone on the left side of the heart, impact on right heart function and pulmonary vascular resistance (PVR) has not been well studied

Objective:

To determine the effects of Dexamethasone on echocardiographic measures of PVR and right heart performance.

Design/Methods: This prospective cohort study was conducted at a neonatal intensive care unit in Southwestern Ontario between March 2019 to July, 2022 after obtaining ethical approval. Neonates < 30 weeks gestational age, who needed Dexamethasone to prevent /treat CLD were eligible. We conducted echocardiograms at 3 time points – first prior to initiation of Dexamethasone (Echo 1), a second one at 24- 48 hours of completing Dexamethasone (Echo 2) and third at 7-14 days after course completion (Echo 3). PVR was measured by ratio of Pulmonary Acceleration Time to Right Ventricular Ejection Time (PAAT:RVET) and right heart performance was measured using Tricuspid Annular Systolic Plane Excursion (TAPSE), RV S’ by Tissue Doppler, Right Ventricular Fractional Area Change (RV FAC) and Right Ventricular Velocity Time Integral ( RV VTI). Chi Square /Mc Nemar Test and paired T test were used as appropriate.

Results:

28 neonates with mean gestational age of 25 weeks and birthweight of 652 grams were included. Mean cumulative dose of Dexamethasone was 0.98 mg/kg given over 8-10 days. Analysis of echocardiographic parameters before Dexamethasone and at treatment completion (Table 1) showed a significant improvement in RV FAC (.45 vs .49, P 0.025) and in TAPSE (.65cm vs .70 cm ,P .013). RV S’, RV VTI, PAAT:RVET ratio appeared to be similar. Left ventricular ejection function were similar, with a statistically significant increase in LV s’ (4.77 vs 6.01, P .006) . Left ventricular wall thickness did not show a significant increase. Longitudinal analysis at three time points, showed a statistically significant increase in RV FAC [0.02 units (95%CI=0.00 – 0.04), p=0.037],TAPSE [0.09 units (95%CI=0.06 – 0.13), p< 0.001] and reduction in Eccentricity Index [0.07 units (95%CI=-0.14 – -0.01), p=0.030.]. As expected, respiratory parameters showed significant improvement during the treatment course.

Conclusion(s): Use of postnatal dexamethasone for prevention/treatment of CLD in premature neonates, resulted in expected improvement in respiratory status along with significant improvement in echocardiographic measures of right heart performance.