An integrated framework to quantitatively link mouse-specific hemodynamics to aneurysm formation in angiotensin II-infused ApoE -/- mice.

Locally disturbed flow has been suggested to play a (modulating) role in abdominal aortic aneurysm (AAA) formation, but no longitudinal studies have been performed yet due to (a.o.) a lack of human data prior to AAA formation. In this study we made use of recent advances in small animal imaging technology in order to set up entirely mouse-specific computational fluid dynamics (CFD) simulations of the abdominal aorta in an established ApoE -/- mouse model of AAA formation, combining (i) in vivo contrast-enhanced micro-CT scans (geometrical model) and (ii) in vivo high-frequency ultrasound scans (boundary conditions). Resulting areas of disturbed flow at baseline were compared to areas of AAA at end-stage. Qualitative results showed that AAA dimension is maximal in areas that are situated proximal to those areas that experience most disturbed flow in three out of four S developing an AAA. Although further quantitative analysis did not reveal any obvious relationship between areas that experience most disturbed flow and the end-stage AAA dimensions, we cannot exclude that hemodynamics play a role in the initial phases of AAA formation. Due to its mouse-specific and in vivo nature, the presented methodology can be used in future research to link detailed and animal-specific (baseline) hemodynamics to (end-stage) arterial disease in longitudinal studies in mice.