Premium
Flow‐induced Platelet Activation and Damage Accumulation in a Mechanical Heart Valve: Numerical Studies
Author(s) -
Alemu Yared,
Bluestein Danny
Publication year - 2007
Publication title -
artificial organs
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.684
H-Index - 76
eISSN - 1525-1594
pISSN - 0160-564X
DOI - 10.1111/j.1525-1594.2007.00446.x
Subject(s) - shear stress , platelet activation , platelet , blood flow , mechanics , mechanical heart , heart valve , turbulence , materials science , cardiology , biomedical engineering , medicine , physics
A model for platelet activation based on the theory of damage, incorporating cumulative effects of stress history and past damage (senescence) was applied to a three‐dimensional (3‐D) model of blood flow through a St. Jude Medical (SJM) bileaflet mechanical heart valve (MHV), simulating flow conditions after implantation. The calculations used unsteady Reynolds‐averaged Navier–Stokes formulation with non‐Newtonian blood properties. The results were used to predict platelet damage from total stress (shear, turbulent, deformation), and incorporate the contribution of repeated passages of the platelets along pertinent trajectories. Trajectories that exposed the platelets to elevated levels of stress around the MHV leaflets and led them to entrapment within the complex 3‐D vortical structures in the wake of the valve significantly enhanced platelet activation. This damage accumulation model can be used to quantify the thrombogenic potential of implantable cardiovascular devices, and indicate the problem areas of the device for improving their designs.