Mette Olufsen, North Carolina State University

Title: The Cardiovascular System

Friday January 25th, 4pm, Phillips 332
(refreshments served in Phillips 330 starting at 3:30)

Abstract: The cardiovascular system has given rise to numerous models ranging from lumped parameter models to complex 3D fluid dynamics models. In this talk I will discuss aspects of these models. First I will discuss how properties of the arterial wall can be mapped using an elastic and a viscoelastic model validated against data from 7 arteries from 11 sheep. Results of this study have shown that elastic properties including Young's modulus and the vessel wall thickness varied across locations (smaller arteries were stiffer than larger arteries) while viscoelastic relaxation parameters did not differ significantly across locations. We also showed that for all locations, the inclusion of viscoelastic behavior is important to capture pressure-area dynamics. Second, Ill present a 1D model of the circle of Willis that includes viscoelasticity. This model is validated against data from a healthy young subject. Results of this study showed that realistic mapping of the geometry of the circle of Willis is important to predict blood flow and pressure. Finally, Ill discuss how structured tree model can be used to predict pressure drop along the small arteries and arterioles. This last model can either be used as outflow boundary conditions for a 1D model, or in itself e.g. coupled to a model predicting the return in the venous vascular network.