Multi-layered nature of the wall of the carotid-artery bifurcation on hemodynamic and mechanical stress and strain

Arterial diseases, namely atherosclerosis, are believed to be a product of abnormal changes in both hemodynamic and non-hemodynamic factors. In order to explore the role of different factors in initiation and progression of this disease, a CFD technique was applied to study Interaction between the structure of the artery and blood flow for different suggested models that were used to describe mechanics of vessel wall. This study presents a three-dimensional, steady state simulation of blood flow through the single and double layered carotid artery bifurcation using fluid - structure interaction (FSI) method. The wall shear stress and mechanical stress/strain are computed and analyzed under two different sets of steady state boundary conditions. Blood was treated as Newtonian fluid in this study. To better understand the importance of layered nature of the wall and also the importance of different types of boundary conditions, a comprehensive comparison was drawn between results of all compliant and rigid models. Under steady state boundary condition, considering a layered nature for the wall may not affect the local hemodynamic considerably but in comparison with single-layered model it has significant effects on total mechanical stress/strain and leads to a more pessimistic estimation.