TY  - JOUR
N2  - Platelet activation induced by shear stresses and non-physiological flow field generated by bileaflet mechanical heart valves (BMHVs) leads to thromboembolism, which can cause fatal consequences. One of the causes of platelet activation could be intermittent regurgitation, which arises due to asynchronous movement and rebound of BMHV leaflets during the valve closing phase. In this numerical study, the effect of intermittent regurgitation on the platelet activation potential of BMHVs was quantified by modeling a BMHV in the straight and anatomic aorta at implantation tilt angles 0°, 5°, 10°, and 20°. A fully implicit Arbitrary Lagrangianâ??Eulerian-based Fluidâ??Structure Interaction formulation was adopted with blood modeled as a multiphase, non-Newtonian fluid. Results showed that the intermittent regurgitation and consequently the platelet activation level increases with the increasing implantation tilt of BMHV. For the straight aorta, the leaflet of the 20° tilted BMHV underwent a rebound of approximately 20° after initially closing, whereas the leaflet of the 10°, 5°, and 0° tilted BMHVs underwent a rebound of 8.5°, 3°, and 0°, respectively. For the anatomic aorta, the leaflet of the 20° tilted BMHV underwent a rebound of approximately 24° after initially closing, whereas the leaflet of the 10°, 5°, and 0° tilted BMHVs underwent a rebound of 14°, 10°, and 7°, respectively. For all the implantation orientations of BMHVs, intermittent regurgitation and platelet activation were always higher in the anatomic aorta than in the straight aorta. The study concludes that the pivot axis of BMHV must be implanted parallel to the aortic root's curvature to minimize intermittent regurgitation and platelet activation. © 2019 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.
VL  - 44
JF  - Artificial Organs
AV  - none
EP  - E39
KW  - Chemical activation; Non Newtonian flow; Non Newtonian liquids; Platelets; Shear flow; Shear stress; Valves (mechanical)
KW  -  Aortic root; Aortic root geometry; Bileaflet mechanical heart valves; Implantation tilting angle; Intermittent regurgitation; Numerical investigations; Physiological flow; Platelet activation; Stress flow; Tilting angle
KW  -  Blood vessels
KW  -  aortic flow; aortic root; Article; computer simulation; equipment design; heart hemodynamics; kinematics; mathematical computing; mathematical model; mitral valve regurgitation; priority journal; shear stress; thrombocyte activation; transcatheter aortic valve implantation; adverse event; aortic regurgitation; aortic valve; biological model; biomechanics; blood; computer simulation; devices; heart valve prosthesis; heart valve replacement; hemodynamics; human; pathophysiology; prosthesis design; surgery; thromboembolism
KW  -  Aortic Valve; Aortic Valve Insufficiency; Biomechanical Phenomena; Computer Simulation; Heart Valve Prosthesis; Heart Valve Prosthesis Implantation; Hemodynamics; Humans; Models
KW  -  Cardiovascular; Numerical Analysis
KW  -  Computer-Assisted; Platelet Activation; Prosthesis Design; Thromboembolism
PB  - John Wiley and Sons Inc
UR  - https://www.scopus.com/inward/record.uri?eid=2-s2.0-85076143780&doi=10.1111%2faor.13536&partnerID=40&md5=ac882ee26da2c6194010fa614b0a476e
SN  - 0160564X
TI  - Numerical investigation on the effect of bileaflet mechanical heart valve's implantation tilting angle and aortic root geometry on intermittent regurgitation and platelet activation
ID  - scholars13506
A1  - Abbas, S.S.
A1  - Nasif, M.S.
A1  - Al-Waked, R.
A1  - Meor Said, M.A.
Y1  - 2020///
N1  - cited By 7
SP  - E20
IS  - 2
ER  -