Abstract

The hemostatic system has evolved to prevent the loss of blood at the site of vascular injury. The response is rapid to limit bleeding and is regulated to prevent excessive clotting that can limit flow. The processes that are involved in the assembly of a thrombus (blood clot) include complex interactions among multiple molecular and cellular components in the blood and vessel wall occurring under fluid flow. Formation of a thrombus (thrombogenesis) involves the close interplay between many processes that occur at different scales (subcellular, cellular and multicellular). In the past, these processes have been studied separately.

In this talk an extended multi-scale model will be described for studying the formation of platelet thrombi in blood vessels. The model describes the interplay between viscous, incompressible blood plasma, activated and non-activated platelets, as well as other blood cells, activating chemicals, fibrinogen and vessel walls. The macroscale dynamics of the blood flow is represented by the continuous submodel in the form of the Navier-Stokes equations. The microscale cell-cell interactions are described by extended stochastic lattice and off-lattice models. Simulations indicate that increase in flow rates leads to greater structural heterogeneity of the clot. As heterogeneous structural domains within the clot affect thrombus stability, understanding the factors influencing thrombus structure is of significant biomedical importance.

Xu, Z., Chen, N., , Kamocka, M.M., Rosen, E.D., and M.S. Alber [2008], Multiscale Model of Thrombus Development, Journal of the Royal Society Interface 5 705-722.

Xu, Z., Chen, N., Shadden, S., Marsden, J.E., Kamocka, M.M., Rosen, E.D., and M.S. Alber, Study of Blood Flow Impact on Growth of Thrombi Using a Multiscale Model, Soft Matter DOI :10.1039/b300001a (to appear).