Computational Fluid Dynamics Analysis of Blood Flow in an Abdominal Aorta with an Infrarenal Aneurysm Post `Chimney` Endovascular Aneurysm Repair (ChEVAR)

Abdominal aortic aneurysms (AAAs) are a key cause of death in the elderly population throughout the western world. They predominantly form in the infrarenal aorta. AAAs that develop near the ostia of major arteries are difficult to repair endovascularly using standard stent grafts since these grafts might block the ostia, depriving vital organs of blood. The renal arteries are at the highest risk of blockage. An endovascular alternative to this method is the patient-specific fenestrated stent graft, which takes months to fabricate. The `Chimney` EndoVascular Repair (ChEVAR) technique is an off-the-shelf solution whereby parallel to a stent graft implanted in the aorta to exclude the AAA, additional stent grafts are inserted into each adjacent artery, to maintain their blood flow. The study compares idealized anatomical aorta models following ChEVAR with different chimney graft lengths by numerically (CFD, Fluent) investigating blood flow patterns and shear stresses. The numerical technique is validated by comparing results for a healthy aorta to available literature data.