In vitro study of flow characteristics in abdominal aortic aneurysm

Hemodynamic factors play a key role in the endovascular aneurysm repair of abdominal aortic aneurysm (AAA). This study conducts an in vitro experiment in which a circulating platform for the experiment and modeling of the pulsatility of blood flow in the human body is established and combined with particle image velocimetry The characteristic parameter distribution of intra-tumoral flow under nonsteady conditions is investigated. Results show that counterflow is a crucial factor affecting the distribution of characteristics of nonsteady intra-tumoral flow, and the presence of single-peak pulsatile flow with counterflow causes the effects of counterflow to emerge at the tumor inlet from the near-wall region and then erode gradually to the streamwise flow region. The maximum intra-tumoral shear stress is found to be located at the near-wall region at the tumor inlet and outlet, and the counterflow formed from the attachment of vortices at the near-wall region leads to the drastic change of the intra-tumoral flow state. The results of the present experiment are useful for quantitatively evaluating the key areas of stress distribution in AAA, providing a basis for preventing risks during the implantation of medical devices.