Abbas-Borazjani’s comprehensive model for simulating the coagulation kinetics in medical devices

We develop a generalizable, comprehensive model for simulating the coagulation cascade in Blood Contacting Medical Devices (BCMDs). Coagulation is a platelet-surface mediated process, requiring activated platelets for the binding and conversion of inactive zymogens to active enzymes. Thrombin, the main product of the coagulation cascade, not only converts soluble Fibrinogen to insoluble Fibrin, but also promotes the activation of further platelets. For the numerical methods to precisely predict the coagulation kinetics, therefore, the accurate estimation of platelet activation is critically significant. We propose a novel coagulation model that comprehensively incorporates the shear-, contact-, and enzyme-induced platelet activation caused by BCMDs in general, with application to Mechanical Heart Valves (MHVs) in specific. The surface-adhesion of platelets, and platelet-platelet cohesion is also modelled by tracking several platelet species, both mobile and bound, by solving a system of partial and ordinary differential equations. The model is extended to characterize the dominant mechanism of platelet activation (shear stresses versus foreign contact) in two designs of MHVs, being a Trileaflet MHV (TMHV) and a Bileaflet MHV (BMHV).