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Cardiac Electrophysiology: The Sinoatrial Node in Focus
Mathematics Letters
Volume 4, Issue 4, December 2018, Pages: 59-66
Received: Sep. 27, 2018; Accepted: Nov. 19, 2018; Published: Jan. 3, 2019
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Nzerem Francis Egenti, Department of Mathematics and Statistics, University of Port Harcourt, Port Harcourt, Nigeria
Ugorji Hycinth Chimezie, Department of Mathematics and Statistics, University of Port Harcourt, Port Harcourt, Nigeria
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The integrity of the cardiac cells and muscles is essential for quality of life. The sinoatrial node cells are the definitive cells of cardiac electrophysiology. They are the primary source of action potentials. Lamentably, the question of ion currents that generate the much needed cardiac action potentials is yet to be resolved. The nagging issue of the presence or otherwise of the sodium ion (Na+) in the sino-atrial node cells may cast doubts at the propriety of clinical measures that target some cardiac events. Some literatures suggest the presence of the said ion at the periphery of the sino-atrial node while contending that it is totally absent in the node centre. Other literatures hold that it is present the entire sino-atrial node. In the light of these, this paper proposed a refined model equation of the cardiac sino-atrial node membrane current. The node centre, known to be the origin of cardiac action potential, was given a bit closer look. Physiological delay arising from the flow of a class of calcium ion current (L-Type calcium current), the bastion of the sino-atrial node centre action potential, was also considered. Ostensibly, the timing of specific ion currents during action potentials may furnish some clues on cardiac conditions.
Action Potentials, Cardiac, Delay, Ion Channels, Mathematical, Equations, Periodic, Physiological
To cite this article
Nzerem Francis Egenti, Ugorji Hycinth Chimezie, Cardiac Electrophysiology: The Sinoatrial Node in Focus, Mathematics Letters. Vol. 4, No. 4, 2018, pp. 59-66. doi: 10.11648/
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