Longitudinal Live Imaging-Derived 4D Hemodynamics and Dynamic Tissue Mechanics Across Outflow Tract Morphogenesis
Gening Dong1,2, Jaehyun Rhee2, Shivani J Kumar2
1The Sibley School of Mechanical and Aerospace Engineering, Cornell University, 14853, Ithaca, NY, United States.
Annals of Biomedical Engineering
|February 17, 2026
Summary
Mechanical forces like wall shear stress drive cardiac outflow tract development and septation. This study reveals how blood flow and tissue mechanics influence congenital heart defect formation.
Area of Science:
- Cardiovascular Development
- Biomedical Engineering
- Developmental Biology
Background:
- Cardiac outflow tract (OFT) growth and remodeling are crucial for normal heart development but remain poorly understood.
- Congenital heart defects (CHDs) are often linked to OFT abnormalities, yet the role of mechanical forces is less characterized than genetic factors.
Purpose of the Study:
- To investigate the interplay between dynamic blood flow and tissue mechanics in OFT remodeling.
- To longitudinally quantify OFT hemodynamics and mechanics across key developmental stages.
- To understand the contribution of mechanical forces to OFT development and septation.
Main Methods:
- Developed a novel live high-frequency ultrasound-derived four-dimensional (4D) computational fluid dynamics (CFD) simulation approach.
- Enabled longitudinal tracking of OFT hemodynamics and tissue mechanics in chicken embryos (Hamburger-Hamilton stages 21-27).
Main Results:
- Wall shear stress (WSS) increased over fourfold from HH21 to HH27, correlating with distal OFT extension.
- Proximal OFT experienced greater expansive strains and higher hydrostatic stress compared to the distal OFT.
- Identified a double-helical flow pattern in the OFT lumen, potentially aiding septation and indicating blood flow streaming.
Conclusions:
- Hemodynamic forces and tissue mechanics are identified as key drivers of OFT tissue development.
- Mechanical stimuli significantly contribute to OFT remodeling and septation processes.
- This research advances understanding of how mechanical forces influence OFT development and CHD etiology.
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