Image-based models of cardiac structure with applications in arrhythmia and defibrillation studies.

Department of Biomedical Engineering, Institute for Computational Medicine, Johns Hopkins University, MD, USA.
Journal of electrocardiology (Impact Factor: 1.08). 02/2009; 42(2):157.e1-10. DOI: 10.1016/j.jelectrocard.2008.12.003
Source: PubMed

ABSTRACT The objective of this article is to present a set of methods for constructing realistic computational models of cardiac structure from high-resolution structural and diffusion tensor magnetic resonance images and to demonstrate the applicability of the models in simulation studies. The structural image is segmented to identify various regions such as normal myocardium, ventricles, and infarct. A finite element mesh is generated from the processed structural data, and fiber orientations are assigned to the elements. The Purkinje system, when visible, is modeled using linear elements that interconnect a set of manually identified points. The methods were applied to construct 2 different models; and 2 simulation studies, which demonstrate the applicability of the models in the analysis of arrhythmia and defibrillation, were performed. The models represent cardiac structure with unprecedented detail for simulation studies.

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