title: 4D subject-specific inverse modeling of the chick embryonic heart outflow tract hemodynamics.
abstract: Blood flow plays a critical role in regulating embryonic cardiac growth and development, with altered flow leading to congenital heart disease. Progress in the field, however, is hindered by a lack of quantification of hemodynamic conditions in the developing heart. In this study, we present a methodology to quantify blood flow dynamics in the embryonic heart using subject-specific computational fluid dynamics (CFD) models. While the methodology is general, we focused on a model of the chick embryonic heart outflow tract (OFT), which distally connects the heart to the arterial system, and is the region of origin of many congenital cardiac defects. Using structural and Doppler velocity data collected from optical coherence tomography, we generated 4D ([Formula: see text]) embryo-specific CFD models of the heart OFT. To replicate the blood flow dynamics over time during the cardiac cycle, we developed an iterative inverse-method optimization algorithm, which determines the CFD model boundary conditions such that differences between computed velocities and measured velocities at one point within the OFT lumen are minimized. Results from our developed CFD model agree with previously measured hemodynamics in the OFT. Further, computed velocities and measured velocities differ by [Formula: see text]15 % at locations that were not used in the optimization, validating the model. The presented methodology can be used in quantifications of embryonic cardiac hemodynamics under normal and altered blood flow conditions, enabling an in-depth quantitative study of how blood flow influences cardiac development.
authors.affiliation: Department of Mechanical Engineering, Texas A&M University, College Station, TX, 77843, USA.
authors.forename: Sevan
authors.initials: S
authors.lastname: Goenezen
authors.affiliation: Department of Biomedical Engineering, Oregon Health and Science University, Portland, OR, 97239, USA.
authors.forename: Venkat Keshav
authors.initials: VK
authors.lastname: Chivukula
authors.affiliation: Department of Biomedical Engineering, Oregon Health and Science University, Portland, OR, 97239, USA.
authors.forename: Madeline
authors.initials: M
authors.lastname: Midgett
authors.affiliation: Department of Biomedical Engineering, Oregon Health and Science University, Portland, OR, 97239, USA.
authors.forename: Ly
authors.initials: L
authors.lastname: Phan
authors.affiliation: Department of Biomedical Engineering, Oregon Health and Science University, Portland, OR, 97239, USA. rugonyis@ohsu.edu.
authors.forename: Sandra
authors.initials: S
authors.lastname: Rugonyi
mesh_terms: D000818:Animals; D001783:Blood Flow Velocity / Q000502:physiology; D002642:Chick Embryo; D003198:Computer Simulation; D006321:Heart / Q000502:physiology*; D006439:Hemodynamics; D057446:Hydrodynamics; D008955:Models, Cardiovascular; D011312:Pressure; D013314:Stress, Mechanical; D041623:Tomography, Optical Coherence; D018608:Ultrasonography, Doppler
keywords: Cardiac defects; Chick embryonic heart; Congenital heart disease; Hemodynamics; Inverse methods; Outflow tract; cardiac development