Comparison of pulse wave propagation in viscoelastic and elastic arteries

The goal of this study was to determine the effect of arterial viscoelasticity upon the propagation of the pressure and flow weforms. A computational model of pulse wave propagation in a viscoelastic artery was developed and compared to the solution for an artery with linear elastic properties. An isotropic linear viscoelastic constitutive equation with one time constant, representing a standard linear solid, was used to model the vessel wall. In both the viscoelastic and elastic solutions, the vessel was assumed to behave as a thin walled pressure vessel and exhibit small strains. Fluid viscosity and vessel tapering were neglected. The material constants were obtained by matching in vitro data from human thoracic arteries at 1.25 Hz. The shape of the resulting pressure pulse was altered significantly as it propagated downstream, especially for the viscoelastic model. However, the fundamental frequency was not afflected.