title: Hemodynamic patterning of the avian atrioventricular valve.
abstract: In this study, we develop an innovative approach to rigorously quantify the evolving hemodynamic environment of the atrioventricular (AV) canal of avian embryos. Ultrasound generated velocity profiles were imported into Micro-Computed Tomography generated anatomically precise cardiac geometries between Hamburger-Hamilton (HH) stages 17 and 30. Computational fluid dynamic simulations were then conducted and iterated until results mimicked in vivo observations. Blood flow in tubular hearts (HH17) was laminar with parallel streamlines, but strong vortices developed simultaneous with expansion of the cushions and septal walls. For all investigated stages, highest wall shear stresses (WSS) are localized to AV canal valve-forming regions. Peak WSS increased from 19.34 dynes/cm(2) at HH17 to 287.18 dynes/cm(2) at HH30, but spatiotemporally averaged WSS became 3.62 dynes/cm(2) for HH17 to 9.11 dynes/cm(2) for HH30. Hemodynamic changes often preceded and correlated with morphological changes. These results establish a quantitative baseline supporting future hemodynamic analyses and interpretations.
authors.affiliation: Department of Biomedical Engineering, Cornell University, Ithaca, New York 14853-7501, USA.
authors.forename: Huseyin C
authors.initials: HC
authors.lastname: Yalcin
authors.forename: Akshay
authors.initials: A
authors.lastname: Shekhar
authors.forename: Tim C
authors.initials: TC
authors.lastname: McQuinn
authors.forename: Jonathan T
authors.initials: JT
authors.lastname: Butcher
mesh_terms: D000818:Animals; D001717:Birds / Q000196:embryology*; D001794:Blood Pressure / Q000502:physiology; D019521:Body Patterning / Q000502:physiology*; D002642:Chick Embryo; D003198:Computer Simulation; D003326:Coronary Circulation / Q000502:physiology*; D003971:Diastole / Q000502:physiology; D006351:Heart Valves / Q000000981:diagnostic imaging / Q000196:embryology*; D006439:Hemodynamics / Q000502:physiology*; D007091:Image Processing, Computer-Assisted / Q000379:methods; D014463:Ultrasonography; D054928:Validation Studies as Topic; D055114:X-Ray Microtomography