Analysis of hemodynamic indicators in Bicuspid Aortic Valves using a computational mathematical model

Bicuspid Aortic Valve (BAV) is a congenital cardiac disorder, prevalent in 1%–2% of the general population, where 33% of BAV patients may experience vascular complications. BAV consists in two cusps instead of three, as in a normal valve (Tricuspid Aortic Valve, TAV). This work is devoted to the numerical study of hemodynamic effects in different BAV geometries (2D) using a Fluid Structure Interaction (FSI) method with an Arbitrary Lagrangian Eulerian (ALE) approach. One idealized TAV model and six BAVs corresponding to patient specific models (with aortic root dimensions measured from MRI exams) were analyzed. Comparing BAVs with TAV analysis, BAVs present asymmetric blood flow jets, vortices and larger WSS on the leaflets (in particular on the belly and on the tip), which can be a potential cause for early valvular calcification or exacerbate the existent calcification. In our FSI numerical simulations, applied to all BAV models, we verified: (i) maximum velocity magnitudes greater than 2 m/s; (ii) higher Von Mises stress on the leaflets, with maximum values of 1.0x10 Pa; (iii) abnormal WSS stresses with values greater than 8 N/m on the leaflets (higher WSS values on the pathological fused leaflet).