Influence of mitral valve elasticity on flow development in the left ventricle

The Mitral valve of the human heart has a great relevance for numerous cardiac pathologies; however, the knowledge of relationships between valvular properties and cardiac function is still limited. On one side, this is partly due to the limited resolution of clinical imaging technologies that do not allow routinely visualization of the valve during its motion. On the other, its modeling presents serious challenges either due to the strong flow tissue interaction or because the mechanical properties of its constitutive elements are complex and not measurable in vivo. This work introduces a parametric model of the Mitral valve where the interaction with the blood flow obeys global balances and the overall elastic properties are summarized into a single functional parameter. This is integrated into a numerical model of left ventricular fluid dynamics with the aim to study the effect of varying the valvular stiffness. Results show that the elasticity of the valve influences the amplitude of the mitral opening, while the timings of opening/closure are driven by the transmitral blood flow due to the ventricular dynamics. In addition, the increase of stiffness increases the transvalvular pressure gradients required to ensure the same flow. These results are discussed in relation to parameters for monitoring valvular stiffness that are accessible through clinical imaging. (C) 2019 Elsevier Masson SAS. All rights reserved.