Sinuatrial Nodal Branch of Right Coronary Artery

Origin

The sinuatrial branch is one of the small atrial branches. It arises on the anterior aspect of the right atrium. However, it may originate along the lateral or sometimes the poster aspect of the right atrium (Standring, 2016). The sinuatrial nodal artery may also arise from the circumflex branch of the left coronary artery in 40% of individuals (Moore, Dalley and Agur, 2013; Pejković et al., 2008).

Course

The sinuatrial nodal branch typically courses between the right atrial appendage and the aorta. Despite its variable origin, it winds around the superior vena cava and gives off small branches as it courses towards the sinuatrial node.

Branches

There are several small branches which extend along the right and left atria. It also gives a larger branch to the crista terminalis, which courses through the sinuatrial node.

Supplied Structures

The sinuatrial nodal branch contributes to the vascular supply of the right atrium and supplies the sinuatrial node.

List of Clinical Correlates

- Coronary artery disease

- Coronary atherosclerosis

- Coronary bypass graft

- Coronary angioplasty

- Coronary occlusion

- Coronary revascularization

- Coronary artery fistula

References

Moore, K. L., Dalley, A. F. and Agur, A. M. R. (2013) Clinically Oriented Anatomy. Clinically Oriented Anatomy 7th edn.: Wolters Kluwer Health/Lippincott Williams & Wilkins.

Pejković, B., Krajnc, I., Anderhuber, F. and Kosutić, D. (2008) 'Anatomical aspects of the arterial blood supply to the sinoatrial and atrioventricular nodes of the human heart', J Int Med Res, 36(4), pp. 691-8.

Standring, S. (2016) Gray's Anatomy: The Anatomical Basis of Clinical Practice. Gray's Anatomy Series 41st edn.: Elsevier Limited.