Hemodynamic and Structural Comparison of Human Fetal Heart Development Between Normally Growing and Hypoplastic Left Heart Syndrome-Diagnosed Hearts

Abstract

Congenital heart defects (CHDs) affect a wide range of societies with an incidence rate of 1.0–1.2%. These defects initiate at the early developmental stage and result in critical health disorders. Although genetic factors play a role in the formation of CHDs, the occurrence of cases in families with no history of CHDs suggests that mechanobiological forces may also play a role in the initiation and progression of CHDs. Hypoplastic left heart syndrome (HLHS) is a critical CHD, which is responsible for 25–40% of all prenatal cardiac deaths. The comparison of healthy and HLHS hearts helps in understanding the main hemodynamic differences related to HLHS. Echocardiography is the most common imaging modality utilized for fetal cardiac assessment. In this study, we utilized echocardiographic images to compare healthy and HLHS human fetal hearts for determining the differences in terms of heart chamber dimensions, valvular flow rates, and hemodynamics. The cross-sectional areas of chamber dimensions are determined from 2D b-mode ultrasound images. Valvular flow rates are measured via Doppler echocardiography, and hemodynamic quantifications are performed with the use of computational fluid dynamics (CFD) simulations. The obtained results indicate that cross-sectional areas of the left and right sides of the heart are similar for healthy fetuses during gestational development. The left side of HLHS heart is underdeveloped, and as a result, the hemodynamic parameters such as flow velocity, pressure, and wall shear stress (WSS) are significantly altered compared to those of healthy hearts.

Recasting Current Knowledge of Human Fetal Circulation: The Importance of Computational Models

“…The human fetal heart can be reliably imaged using ultrasound beginning at mid-gestation [ 145 ]. Despite the rapid fetal heartbeat, rigid wall simulations of the heart wall (myocardium) can lead to a number of insights [ 146 , 147 ]. Depending on the question being asked, FSI simulations may prove more appropriate.…”

Deep Learning Technique for Congenital Heart Disease Detection Using Stacking-Based CNN-LSTM Models From Fetal Echocardiogram: A Pilot Study

“…HLHS is also associated with anatomical abnormalities of the atrial septum when the superior edge of the septum and/or the primum, deviates posteriorly and leftward, resulting in obstruction of the atrial shunt [15]. The abnormal development in cardiac valves or the left ventricle itself may be caused by HLHS [16,17]. We have recently revealed evolving 2 VOLUME 4, 2023 hemodynamics in normally and HLHS diagnosed human fetuses and demonstrated severe hemodynamic abnormalities in fetal HLHS hearts [18,19].…”

Experimental assessment of cardiovascular physiology in the chick embryo

“…Consequently, alteration of hemodynamics during development significantly alters the developmental trajectory of the cardiovascular system through chronic cardiovascular impairment in vertebrates 7‐9 . Indeed, disturbed hemodynamics during the embryo stages are a major factor contributing to the development of CHDs in humans 10,11 …”

“…[7][8][9] Indeed, disturbed hemodynamics during the embryo stages are a major factor contributing to the development of CHDs in humans. 10,11 Due to difficulties in accessing the human fetus, animal studies are instrumental in studying how hemodynamics contribute to the patterning of the developing heart. The chick embryo (Gallus gallus domesticus) is a particularly well-established model organism for developmental physiology research for over 2000 years, with roots going back to Aristotle.…”