title: Fluid dynamics of coarctation of the aorta and effect of bicuspid aortic valve.
abstract: Up to 80% of patients with coarctation of the aorta (COA) have a bicuspid aortic valve (BAV). Patients with COA and BAV have elevated risks of aortic complications despite successful surgical repair. The development of such complications involves the interplay between the mechanical forces applied on the artery and the biological processes occurring at the cellular level. The focus of this study is on hemodynamic modifications induced in the aorta in the presence of a COA and a BAV. For this purpose, numerical investigations and magnetic resonance imaging measurements were conducted with different configurations: (1) normal: normal aorta and normal aortic valve; (2) isolated COA: aorta with COA (75% reduction by area) and normal aortic valve; (3) complex COA: aorta with the same severity of COA (75% reduction by area) and BAV. The results show that the coexistence of COA and BAV significantly alters blood flow in the aorta with a significant increase in the maximal velocity, secondary flow, pressure loss, time-averaged wall shear stress and oscillatory shear index downstream of the COA. These findings can contribute to a better understanding of why patients with complex COA have adverse outcome even following a successful surgery.
authors.affiliation: Laboratory of Biorheology and Medical Ultrasonics, University of Montreal Hospital Research Center (CRCHUM), Montréal, Québec, Canada ; Biomedical Engineering Department, University of Montreal, Montréal, Québec, Canada ; Laboratory of Cardiovascular Fluid Dynamics, Mechanical and Industrial Engineering Department, Concordia University, Montréal, Québec, Canada.
authors.forename: Zahra
authors.initials: Z
authors.lastname: Keshavarz-Motamed
authors.forename: Julio
authors.initials: J
authors.lastname: Garcia
authors.forename: Lyes
authors.initials: L
authors.lastname: Kadem
mesh_terms: D000465:Algorithms; D001011:Aorta / Q000503:physiopathology; D001017:Aortic Coarctation / Q000503:physiopathology*; D001021:Aortic Valve / Q000002:abnormalities* / Q000503:physiopathology; D000082882:Bicuspid Aortic Valve Disease; D001696:Biomechanical Phenomena; D001794:Blood Pressure; D003198:Computer Simulation; D006349:Heart Valve Diseases / Q000503:physiopathology*; D006439:Hemodynamics; D006801:Humans; D057446:Hydrodynamics; D008954:Models, Biological; D012039:Regional Blood Flow; D013312:Stress, Physiological