Sinoatrial nodal artery

The sinoatrial (SA) nodal artery is the small artery that supplies the sinoatrial (SA) node of the heart (the pacemaker). 

Gross anatomy


Right coronary artery in 60% of cases and the left coronary artery in 40% of cases.


The artery turns posteriorly below the superior vena caval opening.

Variant anatomy

The SA node can arise from its own opening in the anterior aortic sinus. 

A study of 516 SA nodal arteries using MDCT found 96.4% of arteries were single whilst 3.6% were double. In this study only 53.4% of SA nodal arteries originated from the right coronary artery with 43% originating from the left circumflex artery

Other variants include

  • S-shaped variant 4
Anatomy: Thoracic

Anatomy: Thoracic

Article information

rID: 52834
System: Cardiac
Section: Anatomy
Synonyms or Alternate Spellings:
  • SA nodal artery
  • Sinoatrial nodal branch

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