Hemodynamic and mechanical aspects of fenestrated endografts for treatment of Abdominal Aortic Aneurysm

Fenestrated endovascular aneurysm repair (f-EVAR) stent grafts offer an alternative treatment for conventional open heart surgery for patients with juxsta-renal Abdominal Aortic Aneurysms (AAA) that are unsuitable for the common infrarenal endovascular aneurysms repair (EVAR) procedure. The f-EVAR endograft includes branched stent grafts fixed to the aortic endograft main body via designated strengthened fenestrations. Repetitive stresses activated upon the endograft by the pulsatile flow might cause detachment or fracture of branching. Thus, investigation of the flow forces and stresses on the graft may help minimize complications and improve the endograft design. The present work investigates the flow and stress fields of the fenestrated endograft configuration using a fluid structure interaction (FSI) model in order to evaluate risks for graft fracture or detachments. The results show that the f-EVAR dramatically improves the aortic and iliac flow and that elevated cyclic stresses are found at the graft's bifurcation and branches' connections.