title: Non-Newtonian Blood Flow Simulation of Diastolic Phase in Bileaflet Mechanical Heart Valve Implanted in a Realistic Aortic Root Containing Coronary Arteries.
abstract: Coronary arteries, which are branched from the sinuses, have tangible effects on the hemodynamic performance of the bileaflet mechanical heart valve (BMHV), especially in the diastolic phase. To better understand this issue, a computer model of ascending aorta including realistic sinus shapes and coronary arteries has been generated in this study in order to investigate the BMHV performance during diastole. Three-dimensional transient numerical analysis is conducted to simulate the diastolic blood flow through the hinges and in coronary arteries under the assumption of non-Newtonian behavior. Results indicate that as blood flows to the coronary arteries mainly during diastole, leakage flow from the hinge and other gaps will change considering the influence of coronary arteries. In addition, BMHV in the case of aortic replacement will increase blood flow rate into the coronary arteries about 100% as the mechanical valve resistance is higher than a native heart valve. Also, it will change the wall shear stress (WSS) distribution and increase coronary artery disease (CAD) potential. It is found out that although less leakage flow reduces the velocity magnitudes through the gaps, the shear stress acting on blood elements with non-Newtonian assumption will be detrimental in the hinge corner at the ventricular side. High WSS of 1800 Pa is observed at beginning of diastole at this region.
authors.affiliation: Center of Excellence in Design and Optimization of Energy Systems, School of Mechanical Engineering, College of Engineering, University of Tehran, Tehran, Iran. hanafizadeh@ut.ac.ir.
authors.forename: Pedram
authors.initials: P
authors.lastname: Hanafizadeh
authors.affiliation: Center of Excellence in Design and Optimization of Energy Systems, School of Mechanical Engineering, College of Engineering, University of Tehran, Tehran, Iran.
authors.forename: Nima
authors.initials: N
authors.lastname: Mirkhani
authors.affiliation: Biomedical Engineering, Katholieke Universiteit Leuven, Leuven, Belgium.
authors.forename: Mohammad Reza
authors.initials: MR
authors.lastname: Davoudi
authors.affiliation: Center of Excellence in Design and Optimization of Energy Systems, School of Mechanical Engineering, College of Engineering, University of Tehran, Tehran, Iran.
authors.forename: Mahtab
authors.initials: M
authors.lastname: Masouminia
authors.affiliation: Center of Excellence in Design and Optimization of Energy Systems, School of Mechanical Engineering, College of Engineering, University of Tehran, Tehran, Iran.
authors.forename: Keyvan
authors.initials: K
authors.lastname: Sadeghy
mesh_terms: D001011:Aorta / Q000033:anatomy & histology / Q000502:physiology*; D001783:Blood Flow Velocity; D003198:Computer Simulation; D003331:Coronary Vessels / Q000033:anatomy & histology / Q000502:physiology*; D003971:Diastole; D004867:Equipment Design; D006350:Heart Valve Prosthesis; D006439:Hemodynamics; D006801:Humans; D008953:Models, Anatomic; D008955:Models, Cardiovascular
keywords: Bileaflet mechanical heart valve; Coronary arteries; Diastolic phase; Non-Newtonian; Numerical simulation