In
electrocardiography, the atrial action potential are
action potential
An action potential occurs when the membrane potential of a specific cell location rapidly rises and falls. This depolarization then causes adjacent locations to similarly depolarize. Action potentials occur in several types of animal cells, ...
s that occur in the
heart atrium
The atrium ( la, Ätrium, , entry hall) is one of two upper chambers in the heart that receives blood from the circulatory system. The blood in the atria is pumped into the heart ventricles through the atrioventricular valves.
There are two at ...
. They are similar to
ventricular action potential with the exception of having a more narrow phase 2 (plateau phase) due to a smaller calcium influx. Also, in comparison to the ventricular action potential, atrial action potentials have a more gradual
repolarization
In neuroscience, repolarization refers to the change in membrane potential that returns it to a negative value just after the depolarization phase of an action potential which has changed the membrane potential to a positive value. The repolarizat ...
period. This indicates that the atria's repolarization currents are not very large and they do not undergo a large repolarization peak.
[Vigmond E.J, Tsoi V, Yin Y, Page P, & Vinet A. (2009). Estimating Atrial Action Potential Duration from Electrograms. IEEE Transactions on Biomedical Engineering (pp. 1546-1555). Vol. 56, No 5. Retrieved on March 27, 2012.]
See also
Cardiac action potential
The cardiac action potential is a brief change in voltage ( membrane potential) across the cell membrane of heart cells. This is caused by the movement of charged atoms (called ions) between the inside and outside of the cell, through proteins c ...
References
Cardiac electrophysiology
Action potentials
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