SPATIOTEMPORAL WAVEFRONT PROPAGATION IN 3D GEOMETRIC EXCITABLE HEART TISSUE

The electrochemical phenomena in the heart were simulated using a specifically simplified three dimensional model based on the cellular physiological concepts. The resulting CEP model (Combined Electrochemical Path), was shown to have the advantage of presenting the electrochemical interactions between various cellular substructures. The cellular architecture in the model follows the non-heterogeneity of the heart structure accompanied by gap junctions representing cellular interconnections. The evaluation is performed through comparisons made between the CEP simulation results and the reported characteristics of various pacemaker heart cells, obtained when the cells were investigated individually. Furthermore, it is shown that spatiotemporal propagation of the electromechanical wave, influenced by the characteristics of 3D geometric architecture in an excitable heart tissue, alters the individual cellular electrophysiological behaviour. The simplified heart geometry is introduced through 18 layers with 25 cells in each layer The CEP model could be adopted as a preliminary basis towards understanding the electrophysiology and pharmacology properties of spatiotemporal wavefront propagation in heart cells.

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