Generation of histo-anatomically representative models of the individual heart: tools and application

Abstract

This paper presents methods to build histo-anatomically detailed individualized cardiac models. The models are based on high-resolution three-dimensional anatomical and/or diffusion tensor magnetic resonance images, combined with serial histological sectioning data, and are used to investigate individualized cardiac function. The current state of the art is reviewed, and its limitations are discussed. We assess the challenges associated with the generation of histo-anatomically representative individualized in silico models of the heart. The entire processing pipeline including image acquisition, image processing, mesh generation, model set-up and execution of computer simulations, and the underlying methods are described. The multifaceted challenges associated with these goals are highlighted, suitable solutions are proposed, and an important application of developed highresolution structure-function models in elucidating the effect of individual structural heterogeneity upon wavefront dynamics is demonstrated.

Nonlinear physics of electrical wave propagation in the heart: a review

“…For the rest of the review we will consider the monodomain description of cardiac tissue propagation Eq. (28). Although this is not a correct description for two and three-dimensional tissue [50], since the intracellular medium is more anisotropic than the extracellular medium, it is usually a sufficient description of action potential propagation in most situations.…”

“…The effect of anisotropy can be incorporated into a model of wave propagation in cardiac tissue by the modification of the diffusion coefficient in the cable equation (28). In the monodomain approach the diffusion tensor is usually determined by two diffusion coefficient values: one in the direction of fast propagation (D ) and a second value for the two perpendicular directions (D ⊥ ).…”

“…Recently, many efforts have been undertaken to employ information on cardiac anatomy and geometry from MRI imaging, histology and other experimental techniques in order to built realistic models of three dimensional propagation. We do not cover these topics here and refer to the articles by Plank, Bishop, Clayton, Smaill, Lamata and colleagues [28][29][30][31][32].…”

Modeling Defibrillation

“…FEM and FVM are both very well suited for spatial discretizations of complex geometries with smooth representations of the boundaries, which is a key feature when polarization patterns induced via extracellularly applied currents are to be studied. Both FVM and FEM have been used to model electrical activity in anatomical realistic models of the atria (Harrild & Henriquez, 2000;Seemann et al, 2006;Vigmond et al, 2004;Virag et al, 2002) as well as the ventricles (Ashihara et al, 2008;Plank et al, 2009;Potse et al, 2006;Ten Tusscher et al, 2007). Mesh generation requirements are similar for both techniques, that is, the domain of interest has to be tessellated into a set of non-overlapping and conformal geometric primitives (Fig.…”

Comparing measured and simulated wave directions in the left atrium – a workflow for model personalization and validation

“…General models of the heart have been created and validated with respect to average parameters of cardiac anatomy and physiology [8] . For applications regarding diagnosis and therapy of individual patients, however, simulation parameters have to be personalized for each individual [16,21] .…”