SA node


Also found in: Dictionary, Thesaurus, Medical, Wikipedia.
Related to SA node: AV node

SA node

[¦es¦ā ′nōd]
(anatomy)
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
Mentioned in ?
References in periodicals archive ?
If not, then vagomimetic anesthetic drugs must be used with caution to avoid hypervagotonic activity to the SA node.
Sometimes, it can occur in highly trained athletes who have "high vagal tone," a condition that affects the SA node and slows the heartbeat.
In 70 cases, the artery was found to be single vessel (93.33%) which supply SA node. Dual blood supply was seen in 5 cases (6.67%).
Its job is to conduct electricity in a rapid and organized fashion from the SA node to the AV node and then down through the lower conduction pathways to the ventricles.
Although SA node has been demonstrated in other birds, there is still some doubt as to its position and even its presence as a discrete node in birds [17].
To prevent anarchy in the heart's electrical system, the pacemaker in the right atrium, the SA node, drives the show Specialized conductive tissue transmits impulses initiated at the SA node to the AV node near the ventricle and then throughout the heart muscle.
SA node is the natural pacemaker of the heart, controlling the rhythm of the heart by sending electrical impulses.
Medical conditions that affect the SA node or the propagation of the contraction signal to the ventricles are the types of heart problems for which a pacemaker may be appropriate.
During periods when the SA node produces its own electrical signal, the pacemaker does nothing but monitor.
The research team point out that the way electrical signals are generated in the SA node - and hence the heart rate - are far from simple.