Document Type : Full Research Paper


1 Biomechanics Division, Department of Biomedical Engineering, AmirKabir University of Technology

2 Faculty of Medicine, Department of Pharmacology, Iran Medical Sciences University

3 Faculty of Medicine, Department of Physiology, Shaheid Beheshti Medical Sciences University



Effective pharmacological analysis encompassing both the pharmacodynamics and the pharmacokinetics of the heart, dictates the necessity for responses made by the main channel receptors, to be appropriately modelled. This approach is of critical value when the pharmacological responses of the organ during pathological states are under investigation. To this effect, the electrochemical phenomenon in the heart was simulated using a specifically simplified three dimensional model based on the cellular physiological concepts. Various advanced models for different types of heart cells were combined to produce a three dimensional model capable of describing the electrophysiological, electrochemical and geometric characteristics of a heart in a non-pathological state. Various cell type models such as central and peripheral SA node, AV node, atrial myocyte, ventricular myocyte, and specialized cells for rapid conductance like purkinje fibres were included in the 3D model. The cellular architecture in the model follows the non-heterogeneity of the heart structure accompanied by gap junctions representing cellular interconnections. Here the transport of Na+, Ca++, K+ and CL- was primarily governed by such factors as electrical and chemical potential gradients along with other energetic mechanisms. The simplified heart geometry is introduced through 18 layers with 25 cells in each layer. Model equations were solved to simulate a one second using a 2.6 GHz Pentium IV PC. The simulation was performed utilizing MA TLAB programming language which provides effective visualization capabilities. The CEP model could be adopted as a preliminary basis towards individualizations in pharmacology and electrophysiology.


Main Subjects

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