An image-based computational hemodynamics study of the Systolic Anterior Motion of the mitral valve

Polygonal surface processing and mesh generation tools for the numerical simulation of the cardiac function

“…However, in some applications we could be interested to attach a given surface to a reference surface, by deforming its boundary ring onto the reference one. In Figure 5, as an example of this situation, we show a case that may happen for example, for patient‐specific hemodynamic simulations, 28 when only a part of the computational domain can be reconstructed from medical images: the left ventricle endocardium (in gray) is segmented from a short‐axis cine‐MRI—that in standard clinical exam typically captures only the ventricular geometry—while the remaining left‐heart comes from a template geometry, in this case the Zygote Solid Heart Model 15 . In order to address this situation, we propose here a new algorithm that exploits the solution of a Laplace‐Beltrami equation.…”

“…The harmonic‐extension algorithm succeeds in recovering the fibers on the missing regions (Figure 9, right), even in the case of sharp changes (see e.g., the uppermost region). Another possible example concerns the image‐based hemodynamics simulations in hybrid patient‐specific/template geometries (see Figure 5), where the deformation field reconstructed from dynamic medical images—for example, on the left‐ventricle—can be harmonically extended to the rest of the template domain 28 …”

“…This kind of refinements is necessary when the valve is treated as an immersed surface in a fluid‐dynamics model 46 without the necessity of using a conforming mesh with its surface. Indeed, in this cases the valve can be modeled as an implicit surface without the necessity of generating a fluid mesh conforming with its leaflets 25,28 …”

“…In this work electrophysiology simulations on a four‐chambers cardiac geometry were performed, as shown in Figure 17A. This complex mesh has been generated by exploiting most of the proposed algorithms of this paper, especially the ones concerning tagging, connections, and mesh‐size function definition; in their multiscale study of the cardiac active mechanics, Regazzoni et al 92 used our algorithms to generate a left‐ventricular mesh for electro‐mechanical simulations, as shown in Figure 17B; Fumagalli et al 28 performed a computational hemodynamics study of the left heart to assess the pathological systolic anterior motion of the mitral valve, as shown in Figure 17C. They used both the harmonic‐connection and harmonic‐extension algorithms in order to connect the patient‐specific ventricle with a template geometry and to extend the image‐based displacement field on the whole domain.…”

“…Starting from these general considerations, in the literature we can find a variety of computational studies focused on completely different aspects of the cardiac function: standalone electrophysiology simulations 17‐19 often focused on particular pathologies and clinical applications 13,20 ; electromechanics studies 2,7,21,22 ; fluid‐dynamics simulations involving the cardiac valve modeling 23‐28 ; and, more seldom, full electro‐mechano‐fluid simulations of the heart, albeit with some simplifications 29,30 …”