title: An animal-specific FSI model of the abdominal aorta in anesthetized mice.
abstract: Recent research has revealed that angiotensin II-induced abdominal aortic aneurysm in mice can be related to medial ruptures occurring in the vicinity of abdominal side branches. Nevertheless a thorough understanding of the biomechanics near abdominal side branches in mice is lacking. In the current work we present a mouse-specific fluid-structure interaction (FSI) model of the abdominal aorta in ApoE(-/-) mice that incorporates in vivo stresses. The aortic geometry was based on contrast-enhanced in vivo micro-CT images, while aortic flow boundary conditions and material model parameters were based on in vivo high-frequency ultrasound. Flow waveforms predicted by FSI simulations corresponded better to in vivo measurements than those from CFD simulations. Peak-systolic principal stresses at the inner and outer aortic wall were locally increased caudal to the celiac and left lateral to the celiac and mesenteric arteries. Interestingly, these were also the locations at which a tear in the tunica media had been observed in previous work on angiotensin II-infused mice. Our preliminary results therefore suggest that local biomechanics play an important role in the pathophysiology of branch-related ruptures in angiotensin-II infused mice. More elaborate follow-up research is needed to demonstrate the role of biomechanics and mechanobiology in a longitudinal setting.
authors.affiliation: IBiTech-bioMMeda, Ghent University - iMinds Medical IT, De Pintelaan 185B, 9000, Ghent, Belgium, bram.trachet@ugent.be.
authors.forename: Bram
authors.initials: B
authors.lastname: Trachet
authors.forename: Joris
authors.initials: J
authors.lastname: Bols
authors.forename: Joris
authors.initials: J
authors.lastname: Degroote
authors.forename: Benedict
authors.initials: B
authors.lastname: Verhegghe
authors.forename: Nikolaos
authors.initials: N
authors.lastname: Stergiopulos
authors.forename: Jan
authors.initials: J
authors.lastname: Vierendeels
authors.forename: Patrick
authors.initials: P
authors.lastname: Segers
mesh_terms: D000758:Anesthesia; D000804:Angiotensin II / Q000009:adverse effects / Q000494:pharmacology; D000818:Animals; D001012:Aorta, Abdominal / Q000503:physiopathology*; D017544:Aortic Aneurysm, Abdominal / Q000139:chemically induced / Q000503:physiopathology*; D004195:Disease Models, Animal; D051379:Mice; D018345:Mice, Knockout; D008955:Models, Cardiovascular
chemical_list: D000804:Angiotensin II