Moving Domain Computational Fluid Dynamics to Interface with an Embryonic Model of Cardiac Morphogenesis

• DOI: 10.1371/journal.pone.0072924
• Publication Date: 2013-08-23T21:07:01Z
• Authors: Juhyun Lee; Mahdi Esmaily Mog...; Ethan Kung; Hung Cao; Tyler Beebe; Yury Miller; Beth L. Roman; Ching-Ling Lien; Neil C. Chi; Alison L. Marsden; Tzung K. Hsiai
• Keywords: Atrioventricular canal; Cardiac cycle

Peristaltic contraction of the embryonic heart tube produces time- and spatial-varying wall shear stress (WSS) pressure gradients (∇P) across atrioventricular (AV) canal. Zebrafish (Danio rerio) are a genetically tractable system to investigate cardiac morphogenesis. The use Tg(fli1a:EGFP)y1 transgenic embryos allowed for delineation two-dimensional reconstruction endocardium. This time-varying motion was then prescribed in moving domain computational fluid dynamics (CFD) model, providing new insights into spatial temporal variations WSS ∇P during development. CFD simulations were validated with particle image velocimetry (PIV) canal, revealing an increase both velocities rates, but decrease duration atrial systole from early later stages. At 20-30 hours post fertilization (hpf), simulation results revealed bidirectional AV canal response peristaltic wall. 40-50 hpf, structure undergoes looping, accompanied by nearly 3-fold magnitude. 110-120 distinct valve, atrium, ventricle, bulbus arteriosus form, incremental increases magnitude ∇P, bi-directional flow. Laminar flow develops at persists hpf. Reynolds numbers 0.07±0.03 hpf 0.23±0.07 (p< 0.05, n=6), whereas Womersley remain relatively unchanged 0.11 0.13. Our highlights hemodynamic changes relation morphogenesis; thereby, 2-D quantitative approach complement imaging analysis.