Cardiac arrhythmia - conduction system overview

The heart is a muscular organ that beats in a rhythmic and coordinated fashion. This property of the heart is mainly due to the presence of a specialized in-house conduction system that generates electrical impulses in an orderly way. This system is known as the cardiac conduction system.

The sequential, rhythmic, coordinated contractions of the heart are the result of the activity of the cardiac conduction system and the presence of gap junctions between adjacent cardiac muscle cells. The cardiac conduction system consists of specialized cardiac cells that are capable of generating and propagating electrical impulses throughout the heart muscle in a coordinated and sequential manner.

The cardiac conduction system consists of the following structures: the sinoatrial (SA) node, the atrioventricular (AV) node, the atrioventricular (AV) bundle or the Bundle of His, the right and left bundle branches, and the Purkinje fibers.

Review Date:5/27/2024
Reviewed By:Michael A. Chen, MD, PhD, Associate Professor of Medicine, Division of Cardiology, Harborview Medical Center, University of Washington Medical School, Seattle, WA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.

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