title: The impact of valve simplifications on left ventricular hemodynamics in a three dimensional simulation based on in vivo MRI data.
abstract: Left ventricle (LV) fluid dynamics and the function of its valves have a crucial impact on clinical diagnosis, treatment and prosthesis design. In this paper, we simulated left ventricular flow using 3D computational fluid dynamics (CFD) based on geometrical and deformational information obtained from MRI. Time variant smoothed LV shapes were extracted from MR images. Corresponding deformation data was interpolated using a cubic-spline interpolation. To evaluate valve influence on LV flow, we compared two planar valve models: physiologically corrected gradually opening/closing model and a simple on/off model. Endocardial displacement was applied to fluid boundary using fluid-structure interaction (FSI) approach. Arbitrary Lagrangian-Eulerian (ALE) formulation was used for unsteady incompressible viscous Newtonian blood flow in the fluid domain. Comparison of results for LV flow with two valve models demonstrated a clear distinction between pressure distribution, velocity distribution, vortex formation/growth/vanishing and energy dissipation especially in the filling phase. Consequently, LV flow simulation by ignoring geometrical details of valves׳ model may lead to non-realistic results in some aspects.
authors.affiliation: Department of Biomedical Engineering, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Iran.
authors.forename: Ali
authors.initials: A
authors.lastname: Imanparast
authors.affiliation: Department of Biomedical Engineering, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Iran. Electronic address: nasser@aut.ac.ir.
authors.forename: Nasser
authors.initials: N
authors.lastname: Fatouraee
authors.affiliation: Department of Polymer Engineering & Color Technology, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Iran.
authors.forename: Farhad
authors.initials: F
authors.lastname: Sharif
mesh_terms: D000328:Adult; D001021:Aortic Valve / Q000502:physiology*; D001783:Blood Flow Velocity / Q000502:physiology; D006439:Hemodynamics; D006801:Humans; D057446:Hydrodynamics; D008279:Magnetic Resonance Imaging; D008297:Male; D008943:Mitral Valve / Q000502:physiology*; D008955:Models, Cardiovascular; D016276:Ventricular Function
keywords: Aortic valve; Computational fluid dynamics; Mitral valve; Vortex structures