Wave pumping mechanism from aortic stretch and recoil in the systemic circulation*

Understanding the hemodynamic interactions between the heart and the vasculature is the crucial step toward developing new diagnostic devices and therapeutic approaches. One such interaction is the physical connection between the proximal ascending aorta, aortic annulus, and the left ventricle (LV). Recent clinical studies have visualized aortic root motion due to the LV systolic long-axis shortening, wherein the aortic root is displaced downward during systole and returns passively to its previous position in diastole. While this displacement results in energy storage in aorta’s spring-like elements, it is unknown whether the stretch-related aortic dynamic mode can result in a wave pumping effect in the aorta, and hence offers the heart a supplementary pumping mechanism. This study is designed to understand the underlying wave pumping mechanism created by aortic stretching and recoil. To investigate this phenomenon, we employ an in-vitro hydraulic model that has hemodynamic properties similar to the human systemic circulation. A driving component is designed and employed to mimic the stretch-related aortic dynamic mode.