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.

Current as ofJuly 22, 2018

Author: Healthwise Staff
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
Martin J. Gabica MD - Family Medicine
John M. Miller MD, FACC - Cardiology, Electrophysiology

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