The Effect of Various Physical Phenomena on Wave Propagations in the Human Aorta

A physiologically-correct mathematical model of blood flow in the human aorta is developed from previously reported experimental data. The blood is assumed as a viscous fluid flowing through a compliant tube. This phenomenon is modeled by combining the Navier-Stokes’ equations and Laplace Law. The model is validated using experimental data collected at a leading specialist catheterisation laboratory. The mathematical model is then manipulated to derive a pressure transfer function between the aortic pressure and the pressure at the iliac bifurcation. The results of a comprehensive senstivity analysis carried out on this transfer function are discussed in this article. This study indicates that Coriolis and viscous effects insignificantly affect the wave propagation characteristics. The effect of arterial tapering on the transfer function is also recorded as insignificant. Changing the stiffness of the tube causes the pressure wave to travel faster through the system. The system natural frequency also increases when the tube wall is stiffened.