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 of: September 7, 2022
Author: Healthwise Staff
Medical Review: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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