Electrical System of the Heart

Electrical system of the heart

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 fibres. The fibres carry the signal and cause the lower chambers (ventricles) to contract.

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

ByHealthwise Staff
Primary Medical Reviewer Rakesh K. Pai, MD, FACC - Cardiology, Electrophysiology
Brian D. O'Brien, MD - Internal Medicine
E. Gregory Thompson, MD - Internal Medicine
Adam Husney, MD - Family Medicine
Specialist Medical Reviewer John M. Miller, MD, FACC - Cardiology, Electrophysiology

Current as ofOctober 5, 2017

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