Fluid-Structure Interaction of Pre- and Post-operative Abdominal Aortic Aneurysms

摘要

Endovascular aneurysm repair (EVAR) is a surgical technique for the treatment of abdominal aortic aneurysms (AAA). The aim of EVAR is to shield the aneurysm from the pressure of arterial blood flow. It has been shown in idealised models that the stress on the aneurysm wall does not reduce to zero after EVAR. A fluid solver (Fluent) and structural solver (Abaqus) were coupled via an external software (MpCCI) to calculate the wall stresses in a patient specific AAA. CT scan data was used to reconstruct both pre- and post-operative models. Simulations indicated that the peak wall stress on the aneurysm was reduced by 95% after EVAR. The highest post-operative stresses were found to exist in locations where the stent-graft was in contact with the artery walls. Post-operative stress patterns may explain how aneurysm morphology changes over time after EVAR.