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
Origin
Right coronary artery in 60% of cases and the left coronary artery in 40% of cases.
Course
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
Related Radiopaedia articles
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