An electromechanical model of cardiac tissue: constitutive issues and electrophysiological effects.

Laboratory of Nonlinear Physics and Mathematical Modeling, Università Campus Bio-Medico, Roma, Italy.
Progress in Biophysics and Molecular Biology (Impact Factor: 3.38). 06/2008; 97(2-3):562-73. DOI: 10.1016/j.pbiomolbio.2008.02.001
Source: PubMed

ABSTRACT We present an electromechanical model of myocardium tissue coupling a modified FitzHugh-Nagumo type system, describing the electrical activity of the excitable media, with finite elasticity, endowed with the capability of describing muscle contractions. The high degree of deformability of the medium makes it mandatory to set the diffusion process in a moving domain, thereby producing a direct influence of the deformation on the electrical activity. Various mechano-electric effects concerning the propagation of cylindrical waves, the rotating spiral waves, and the spiral breakups are discussed.

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