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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.
ByHealthwise StaffPrimary Medical ReviewerRakesh K. Pai, MD, FACC - Cardiology, ElectrophysiologyE. Gregory Thompson, MD - Internal MedicineSpecialist Medical ReviewerJohn M. Miller, MD, FACC - Cardiology, Electrophysiology
Current as ofJanuary 27, 2016
Current as of:
January 27, 2016
Rakesh K. Pai, MD, FACC - Cardiology, Electrophysiology & E. Gregory Thompson, MD - Internal Medicine & John M. Miller, MD, FACC - Cardiology, Electrophysiology
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