Cardiac Arrhythmias: Difference between revisions

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===Phase 2: Plateau===
===Phase 2: Plateau===
The plateau phase represents an equal influx and efflux of ions producing a stable membrane potential. The influx is mediated by Ca<sup>2+</sup> through the open L-type Ca<sup>2+</sup> channels (I<sub>Ca-L</sub>)and the exchange of Na<sup>+</sup> for internal Ca<sup>2+</sup> by the Na<sup>+</sup>/Ca<sup>2+</sup> exchanger. The efflux is the result of outward current carried by K<sup>+</sup> (I<sub>Kr</sub> and Cl<sup>-</sup> ions.
The plateau phase represents an equal influx and efflux of ions producing a stable membrane potential. This plateau phase is predominantly observed in the ventricular action potential. The influx is mediated by Ca<sup>2+</sup> through the open L-type Ca<sup>2+</sup> channels (I<sub>Ca-L</sub>)and the exchange of Na<sup>+</sup> for internal Ca<sup>2+</sup> by the Na<sup>+</sup>/Ca<sup>2+</sup> exchanger. The efflux is the result of outward current carried by K<sup>+</sup> (I<sub>Kr</sub> and Cl<sup>-</sup> ions.


===Phase 3: Final Rapid Repolarization===
===Phase 3: Final Rapid Repolarization===
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