|Abstract:|| This work deals with a numerical study on how the presence of a bicuspid aortic valve influences the hemodynamics in the ascending aorta. In particular it focuses on analysing how the inclusion of the geometry of the valve leaflets affects the results compared with more simplified models that ignore the presence of the leaflets. BAV is the most common congenital heart disease (about 1-2 % of the population) and consists in the fusion of two of the aortic valve leaflets resulting in a bicuspid sistolic orifice instead of the normal tricuspid configuration. This induces an increased prevalence of ascending aortic dilatation and risk of aneurysm in normally functioning valvular regime when compared to tricuspid aortic valve. The main purpose of the thesis is the comparison between numerical simulations obtained in real geometries, with and without valve leaflets. In particular, two real configurations of ascending aorta are studied, a case with a dilated aortic root and a case with physiological dimensions. We have built two meshes for each geometry, one including the presence of the valve leaflets, the other with the simple presence of the valve orifice considered as an inlet in the simulation. We made also a comparison with a simulation on a TAV (tricuspid aortic valve) geometry.
All simulations have been carried out using LifeV, a finite element library for the solution of PDEs. The numerical results show that bicuspid valve causes a significant asymmetry in the blood flow, and that such an asymmetry considerably increases in presence of the valve leaflets.|