Achieving electrical synchronization among sinoatrial (SA) node cells, which is essential for initiating and propagating pacemaker activity, remains a complex and widely discussed issue in cardiac electrophysiology. While several previous studies have proposed theoretical models to explain this synchronization, the majority have been limited to small-scale simulations involving only a few interconnected SA node cells. To address this limitation, the present study introduces a novel computational model of the human SA node grounded in the sequential discharge hypothesis. This model features a three-dimensional (3D) lattice of cells governed by a modified Hodgkin-Huxley (HH) framework, where the membrane dynamics are adjusted using a time constant to simulate realistic propagation of action potentials through gap junctions. Simulation results demonstrate that the proposed model can produce stable oscillatory activity within a physiological heart rate range of 40 to 180 beats per minute (BPM). Furthermore, the 3D network effectively estimates the extracellular electrical potential in the vicinity of the SA node, closely matching the signals recorded by clinical electrodes. These findings suggest that the model offers a more comprehensive and scalable approach for studying the electrical synchronization mechanisms of large populations of SA node cells, particularly in human cardiac tissue.
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Yaghoobi Karimi,R. , Azadi,S. and Rahamni Seryasat,O. (2020). Modeling the Human Sinoatrial Node Based on Sequential Discharge Hypothesis. Transactions on Machine Intelligence, 3(1), 43-56. doi: 10.47176/TMI.2020.43
MLA
Yaghoobi Karimi,R. , , Azadi,S. , and Rahamni Seryasat,O. . "Modeling the Human Sinoatrial Node Based on Sequential Discharge Hypothesis", Transactions on Machine Intelligence, 3, 1, 2020, 43-56. doi: 10.47176/TMI.2020.43
HARVARD
Yaghoobi Karimi R., Azadi S., Rahamni Seryasat O. (2020). 'Modeling the Human Sinoatrial Node Based on Sequential Discharge Hypothesis', Transactions on Machine Intelligence, 3(1), pp. 43-56. doi: 10.47176/TMI.2020.43
CHICAGO
R. Yaghoobi Karimi, S. Azadi and O. Rahamni Seryasat, "Modeling the Human Sinoatrial Node Based on Sequential Discharge Hypothesis," Transactions on Machine Intelligence, 3 1 (2020): 43-56, doi: 10.47176/TMI.2020.43
VANCOUVER
Yaghoobi Karimi R., Azadi S., Rahamni Seryasat O. Modeling the Human Sinoatrial Node Based on Sequential Discharge Hypothesis. Trans. Mach. Intell., 2020; 3(1): 43-56. doi: 10.47176/TMI.2020.43