Pediatric Heart Disease

1357070 - Normal range of left ventricular wall thickness by CMR analysis among healthy children

Wednesday, January 25, 2023

Location: E-POSTER

Presenting Author(s)

LT

Lauren S. Talley, MD

Pediatric Cardiology Fellow
The University of Texas Health Science Center at Houston
Houston, Texas, United States

Primary Author(s)

LT

Lauren S. Talley, MD

Pediatric Cardiology Fellow
The University of Texas Health Science Center at Houston
Houston, Texas, United States

Co-Author(s)

AB

Amulya Buddhavarapu, MBBS

Fellow, Pediatric Cardiac Imaging
The University of Texas Health Science Center at Houston
Houston, Texas, United States
DA

Dilachew Adebo, MD, FSCMR

Associate Professor of Pediatrics
The University of Texas Health Science Center at Houston
Houston, Texas, United States
Arpit Kumar Agarwal, MD, MSc, FSCMR

Assistant Professor of Pediatrics, Medical Director Advanced Cardiac Non-Invasive Imaging and 3D
The Children's Hospital of San Antonio
San Antonio, Texas, United States

Background: Measurements of left ventricular (LV) wall thickness by cardiac magnetic resonance imaging (CMR) currently have no established normal values within the pediatric population and are mostly derived from published data from other imaging modalities. While studies have been published regarding the normal range of LV mass, their applicability to a wider population remains to be determined. A major difficulty has been in determining the optimal method of measurement and establishing a reference normal range of LV mass and wall thickness measurements in the context of rapid and variable growth velocities among pediatric patients. Our study aims to study absolute values of LV wall thickness and mass parameters by CMR among children with structurally normal hearts and no LV pathology. We further assessed the trend of these LV dimensions stratified by gender and body surface area (BSA)

Methods:
Using data from two independent sites, we performed a retrospective analysis of 147 children (36% female) aged 4 to 18 years who underwent routine CMR between 2016 and 2022 due to suspected heart disease and found to have normal findings. Patients with a history of systemic hypertension were also excluded from this study. Direct measurements of interventricular septal wall thickness (IVST) and LV posterior wall thickness (PWT) were made in the ventricular short axis plane on balanced steady state free precession cine images. Measurements were performed in end-diastole at ventricular mid-cavitary level between the papillary muscles as shown in figure 1. Epicardial/endocardial contouring was performed to measure ventricular mass and volumes. All measurements including wall thickness were indexed to body surface area (BSA).

Results: The mean age of the study subjects is 13.15 ± 4.4 years. Mean LV PWT was 4.86 ± 1.42 mm among the entire study population. Mean LV PWT among females was 4.54 ± 1.24 mm and among males was 5.05 ±1.49 mm. Indexed LV PWT was 3.39 ± 1.08 mm/m2. Mean IVST was 6.56 ± 1.59 mm among the entire study population. Mean IVST among females was 6.22 ± 1.36 mm and among males was 6.76 ±1.68 mm. Indexed IVST was 4.57 ± 1.18 mm/m2. Indexed mean LV mass was 49.62 ± 10.63 grams/m2 (Mean absolute LV mass was 74.53 ± 27.45 g). Data of absolute and indexed values stratified by gender is depicted in table 1.

Conclusion: To the best of our knowledge, this is the first multi-center study to propose a standardized approach and location of measurement of LV wall thickness by CMR which is comparable to location of echocardiographic measurements. This analysis successfully provides absolute and indexed normative reference ranges of LV wall thickness among structurally normal hearts. Indexed measurements of LV wall thickness can be a reliable method of assessing wall thickness among the growing children.