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Cardioversion: Electrical System of the Heart

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In the normal heart, electrical impulses pace the rhythm at which the heart contracts and relaxes. The sinoatrial (SA) node triggers the electrical impulse, causing the upper chambers (atria) to contract. The signal travels through the atrioventricular (AV) node to the atrioventricular bundle, which divides into the Purkinje fibers. The fibers carry the signal and cause the lower chambers (ventricles) to contract.

The electrocardiogram (EKG, ECG) tracing above reflects this normal electrical activity.

By Healthwise Staff
Primary Medical Reviewer Rakesh K. Pai, MD, FACC - Cardiology, Electrophysiology
Specialist Medical Reviewer John M. Miller, MD, FACC - Cardiology, Electrophysiology
Current as of March 12, 2014

WebMD Medical Reference from Healthwise

Last Updated: March 12, 2014
This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.

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