Effectiveness of Stent in the Treatment of Renal Artery Aneurysm using FSI Simulation

Renal artery aneurysm (RAA) is a condition that affects approximately ۰.۱% of the general population. The rate of incidence is minimal compared to other type of aneurysm but a high number of ruptures have been reported in pregnancy, especially at the third trimester. The concerning issue is that the maternal mortality rate stretches up to ۵۰% and the fetal mortality rate approaching ۸۵% with a universal loss of the affected kidney. This study aimed at investigating the effectiveness of stent in treatment of RAA using the fluid-structure interaction (FSI) approach. The flow pattern, wall shear stress (WSS), deformation and von Mises stress experienced are compared between RAA model without stent and with Abbott RX Herculink stent. A simple PIV experiment, observing the flow profile was conducted as a validation steps in ensuring the simulation results are reliable and accurate. The findings show that the simulation and PIV data are in good agreement in terms of the flow profile. The presence of stent managed to reduce the blood flow maximum velocity down to ۴۶% and minimized the circulation of blood in the aneurysm dome. As for the WSS, the used of stent succeeded in decreasing the WSS experienced by the wall of aneurysm by ۷۱% and below the baseline level of WSS that could induced rupture. The deformation of RAA and maximum von Mises stress reduced by ۵۸% and ۷۳% respectively when stent is used. In addition, the maximum von Mises stress after the stent placement is lower than the threshold value for the ultimate tensile strength of the tissue. This study concluded that the stent placement is effective in reducing the risk of aneurysm rupture in renal artery it can be one of the baseline for the further study regarding the RAA.

Keywords:

Renal artery aneurysm , Stent , FSI , PIV