sinoatrial node(redirected from Atrial sinus)
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Related to Atrial sinus: SA node
sinoatrial node[¦sī·nō′ā·trē·əl ′nōd]
A bundle of Purkinje fibers located near the junction of the superior vena cava with the right atrium which acts as a pacemaker for cardiac excitation. Abbreviated SA node. Also known as sinoauricular node.