SA Node and AV Node

Electrical pulses in the heart are controlled by special groups of cells called nodes. The SA (sinoatrial) node generates an electrical signal that causes the upper heart chambers (atria) to contract. The signal then passes through the AV (atrioventricular) node to the lower heart chambers (ventricles), causing them to contract, or pump.

The SA node is considered the pacemaker of the heart. Its electrical signals normally cause the atria of an adult's heart to contract at a rate of about 60 to 100 times a minute.

Disturbance anywhere along this electrical pathway can cause irregular heartbeats (arrhythmia).

This information does not replace the advice of a doctor. Healthwise, Incorporated, disclaims any warranty or liability for your use of this information. Your use of this information means that you agree to the Terms of Use. Learn how we develop our content.

© 1995-2021 Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.