A Computational Investigation of Blood Flow in Realistic AAA Stent-Grafts

Abdominal aortic aneurysm (AAA) is treated with two methods — open repair and endovascular repair. The endovascular method has many advantages over open repair, such as shorter hospital stays, non-invasiveness and shorter recovery times but there have been several reported problems with these devices, including graft migration, endoleaks and limb occlusion. Graft migration occurs in approximately 10% of grafts [1] while limb occlusion occurs in 11% of cases [2]. The consequence of endoleaks and migration not being treated may be the ultimate rupture of the aneurysm. The occlusion of iliac graft limbs can lead to peripheral vascular problems such as ischemia and gangrene. Some of the influencing factors on migration, occlusion and endoleaks are fluid, drag, stent-graft angulation and flow characteristics such as Deans flow.