TY - JOUR

T1 - A 2D electro-mechanical model of human atrial tissue using the discrete element method

AU - Brocklehurst, Paul

AU - Adeniran, Ismail

AU - Yang, Dongmin

AU - Sheng, Yong

AU - Zhang, Hengui

AU - Ye, Jianqiao

PY - 2015

Y1 - 2015

N2 - Cardiac tissue is a syncytium of coupled cells with pronounced intrinsic discrete nature. Previous models of cardiac electro-mechanics often ignore such discrete properties and treat cardiac tissue as a continuous medium, which has fundamental limitations. In the present study, we introduce a multi-scale 2D electro-mechanical model for human atrial tissue based on the discrete element method (DEM). In the model, single-cell dynamics are governed by strongly coupling the electrophysiological model of Courtemanche et al. to the myofilament model of Rice et al. with two-way feedbacks. Each cell is treated as a visco-elastic body, which is physically represented by a clump of nine particles. Cell aggregations are arranged in such a way that the anisotropic nature of cardiac tissue due to fibre orientations can be modelled. Each cell is electrically coupled to neighbouring cells, allowing excitation waves to propagate through the tissue. Cell-to-cell mechanical interactions are modelled using a linear contact bond model in DEM. By coupling cardiac electrophysiology with mechanics via the intracellular Ca2+ concentration, the DEM model successfully simulates the conduction of cardiac electrical waves and the corresponding tissue’s mechanical contractions in a 2D tissue model. In conclusion, we have developed a DEM based multi-physics model of cardiac electro-mechanics, allowing for better simulation of cardiac tissue’s discrete and anisotropic natures than traditional continuum mechanics approaches. The developed DEM model is numerically stable and provides a powerful method for studying the electro-mechanical coupling problem in the heart.

AB - Cardiac tissue is a syncytium of coupled cells with pronounced intrinsic discrete nature. Previous models of cardiac electro-mechanics often ignore such discrete properties and treat cardiac tissue as a continuous medium, which has fundamental limitations. In the present study, we introduce a multi-scale 2D electro-mechanical model for human atrial tissue based on the discrete element method (DEM). In the model, single-cell dynamics are governed by strongly coupling the electrophysiological model of Courtemanche et al. to the myofilament model of Rice et al. with two-way feedbacks. Each cell is treated as a visco-elastic body, which is physically represented by a clump of nine particles. Cell aggregations are arranged in such a way that the anisotropic nature of cardiac tissue due to fibre orientations can be modelled. Each cell is electrically coupled to neighbouring cells, allowing excitation waves to propagate through the tissue. Cell-to-cell mechanical interactions are modelled using a linear contact bond model in DEM. By coupling cardiac electrophysiology with mechanics via the intracellular Ca2+ concentration, the DEM model successfully simulates the conduction of cardiac electrical waves and the corresponding tissue’s mechanical contractions in a 2D tissue model. In conclusion, we have developed a DEM based multi-physics model of cardiac electro-mechanics, allowing for better simulation of cardiac tissue’s discrete and anisotropic natures than traditional continuum mechanics approaches. The developed DEM model is numerically stable and provides a powerful method for studying the electro-mechanical coupling problem in the heart.

M3 - Journal article

VL - 2015

JO - Biomed Research International

JF - Biomed Research International

SN - 2314-6133

M1 - 854953

ER -