An In Vitro Analysis of the Influence of the Arterial Stiffness on the Aortic Flow Using Three-Dimensional Particle Tracking Velocimetry

A three-dimensional pulsatile aortic flow in a human ascending aorta is investigated in-vitro in this paper. A non-intrusive measurement technique, 3D Particle Tracking Velocimetry (3D-PTV), has been applied to the anatomically accurate silicon replicas. A compliant and a stiff aortic model were analyzed to better understand the influence of the arterial stiffness. The realistic models are transparent which allows optical access to the investigation domain. Our results showed that increasing the arterial stiffness considerably increases the systolic velocity and hencemean kinetic energy. Quite strikingly, the turbulent kinetic energy is about one order of magnitude higher in the stiffer model during the deceleration phase which manifests that a blood element is exposed to higher shear stresses in the stiffer model. Moreover, we found that the compliant model introduces pressure oscillations during the diastolic phase which are associated with the Windkessel effect.