Speaker
Description
Mathematical and computational models of the heart offer insights into cardiac function that cannot be captured directly by medical imaging alone. Such models can inform patient-specific treatment planning, playing a central role in precision medicine. The mitral valve (MV) plays a important role in the cardiac function, regulating blood flow from the left atrium to the left ventricle. It is commonly impacted by pathologies such as prolapse, regurgitation and stenosis. In this talk, we first develop a fluid-structure interaction (FSI) model of the mitral valve that uses a physiologically realistic description of the MV leaflets and chordae tendineae. We implement this model in a validated immersed-boundary/finite-element framework, exploring the nodal coupling approach, which uses an identical set of points (the nodes of the structural mesh) for both the quadrature rule and Lagrangian interpolant, to obtain a diagonal mass matrix. In general, this requires 5-10 times fewer interaction points than the elemental approach used in previous work, improving the efficiency of simulations. However, leakage through the structure can occur when the structural mesh is relatively coarser than the background Eulerian grid. Results show that this approach is able to capture important characteristics of MV flow, such as vortices around the MV leaflets. Secondly, we explore a FSI model of a commercial phantom MV, that has been designed for learning and practicing leaflet repair. We match our structural mesh, boundary conditions, and the material properties of the leaflets and chordae to the experimental data, and show that our model is capable of reproducing results for leaflet closure, blood flow through the valve and fibre stress on the leaflets.