Modeling the Human Sinoatrial Node Based on Sequential Discharge Hypothesis

Document Type : Original Article


1 Department of Biomedical Engineering, Semnan University, Semnan, Iran

2 Department of Electrical Engineering, Faculty of Technology and Engineering, Adiban Institute of Higher Education, Garmsar, Iran.


The electrical synchronization of human sinoatrial (SA) node cells for propagating the pacemaker activity has always been an important challenge in literatures. Nevertheless, most literatures, that provide hypotheses for the electrical synchronization of SA node cells, only investigated the activity of a very small group of coupled SA node cells. Therefore, this study proposes a novel SA node model based on the sequential discharge hypothesis to estimate the electrical potential around the SA node, which electrodes measure it. This model consists of a three-dimensional regular network of Hodgkin-Huxley (HH) model modified by time constantthat propagates the action potentials of dominant pacemaker through the gap junctions. The results show that the HH model modified in this study not only has adequate capacity for generating oscillations between 40 and 180 beats per minute (BPM), but also their three-dimensional regular network can provide a suitable estimate from the electrical potential around the SA node. Therefore, this model is a good suggestion for the electrical synchronization of large mammalian SA node cells, especially human.


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