Hemodynamical aspects of endovascular repair for aortic arch aneurisms

The presented study is focused on the hemodynamics aspects of thoracic aortic aneurysm and approaches for restoring hemodynamics in the aortic arch. The study includes numerical investigation of the aortic arch hemodynamics of a healthy aorta, aorta with aneurysm, and of two endovascular repairing procedures. The first endovascular repair approach is the total aortic arch hybrid debranching. The second implantation uses chimney graft technique. The analysis includes the fluid dynamics in the aorta and branching arteries under time-dependent physiological conditions. The results show the effect of aneurysm on blood flow in the descending aorta and in aortic arch side branches. In the aneurysmatic case, the aneurysm provokes a highly disturbed flow and large recirculation regions, especially during diastole. Out of the two endovascular techniques, the hybrid procedure was found preferred from hemodynamics point of view, with less disturbed and recirculating regions. Although the chimney procedure requires less manufacturing times and cost, it is associated with higher risks rate, and therefore, it is recommended only for emergency cases. This study may shade light on the hemodynamic factors for these complications, and provide insights on ways to improve the procedure.