Skip to main content

Unfortunately we don't fully support your browser. If you have the option to, please upgrade to a newer version or use Mozilla Firefox, Microsoft Edge, Google Chrome, or Safari 14 or newer. If you are unable to, and need support, please send us your feedback.

Elsevier
Publish with us
Atrioventricular Node
Nervous System

Atrioventricular Node

Nodus atrioventricularis

Read more

Description

The atrioventricular node (or AV node) is located in the base of the right atrium close to the interatrial septum. The AV node is a group of highly specialized cardiac muscle fibers that depolarize and produce action potentials. These electrical impulses are generated automatically in a rhythmic fashion, occurring roughly 40–50 times per minute. Typically, the basal rhythm of the AV node is masked by the higher pace of the SA node, but in pathologic situations, the AV node can take over pacemaker function for the heart.

Like most of the cells of the cardiac conduction system, and unlike typical myocardial cells, the cells of the AV node have few myofibers and are only weakly contractile.

The AV node receives input from the SA node via the three internodal tracts. Additionally, it receives sympathetic and parasympathetic inputs from the cardiac plexus to increase or decrease the rate of firing, respectively. All of these inputs modulate the rate at which the AV node fires an action potential. Once depolarized, the AV node transmits its action potential unidirectionally to the AV bundle, and from there throughout the ventricles (Katz, 2010; Anderson et al., 2009).

Complete Anatomy
The world's most advanced 3D anatomy platform
Try it for Free

References

Anderson, R. H., Yanni, J., Boyett, M. R., Chandler, N. J. and Dobrzynski, H. (2009) 'The anatomy of the cardiac conduction system', Clin Anat, 22(1), pp. 99-113.

Katz, A. M. (2010) Physiology of the Heart. M - Medicine Series: Wolters Kluwer Health/Lippincott Williams & Wilkins Health.

Learn more about this topic from other Elsevier products

Atrioventricular Node

ScienceDirect image

The atrioventricular node is an atrial structure that lies in the apex of the triangle of Koch (formed by the coronary sinus, the tendon of Todaro, and the annular attachment of the septal leaflet of the tricuspid valve).

Explore on ScienceDirect(opens in new tab/window)

Complete Anatomy

The world's most advanced 3D anatomy platform

Complete Anatomy