Numerical simulation of pulse wave propagation in arteries with structured-tree outflow conditions

When constructing the one-dimensional systemic artery tree, the Windkessel model based on parameters describing the total resistance and compliance is generally applied as outflow boundary conditions. However, the Windkessel model does not include wave propagation effects, and moreover, it is not obvious how the parameters should be estimated. Hence, the main purpose of this study is to develop an outflow boundary condition based on the underlying physiology of the arterioles, enabling the prediction of blood flow and pressure in the systemic arteries including the arterioles. The obtained numerical results show the followings. Firstly, we verified that applying the structured tree model as an outflow boundary condition can reproduce the essential characteristics of the arterial pulse better than applying the Windkessel model. Secondly, by analyzing the pulse wave velocity in aorta, we found a correlation between pulse wave velocity and the degree of arteriosclerosis which correspond to the clinical observation.