Effect of Blood Flow Models on the Flow-Induced Vibrations of Coronary Arteries

Human coronary blood flow has been characterised by many various blood models in literature, resulting in discrepancies and contradictions on the effect of flow-induced vibrations and shear thinning on disease progression. With cardiovascular disease the largest cause of death globally, a clearer and more consistent approach to modelling the rheological properties of blood flow is needed. This investigation examines three prominent blood models used in literature and evaluates the flow-induced effects on artery vibration, through fluid-structure interaction (FSI) for the first time, and the implications for disease progression and failure. The FSI model was constructed through finite element methods in ANSYS to model a nonlinear, left main coronary artery with atherosclerotic plaque; the impacts of Newtonian blood and the Carreau and power law non-Newtonian blood models, based on literature, were assessed. The power law model considerably increased von Mises stress, wall shear stress and pressure; this was significant when compared to previous comparisons undertaken whilst assuming the artery as rigid. As wall shear stress in particular is important in disease initiation and progression, the flow-induced effects of non-Newtonian blood models are critical.