Right coronary artery

Function

The RCA leaves the right aortic sinus, dives into the right atrioventricular groove and circles the heart's base. In 80% of people ('right-dominant' circulation) it crosses the crux to supply the posterior descending artery — and with it the inferior wall, the AV node in 90% and the SA node in 60%.

Its marginal branches feed the right ventricle, and its infundibular branch anastomoses with the LAD in the circle of Vieussens — a primitive collateral path.

Blood supply

Right aortic sinus ostium.

Nerve supply

Autonomic vasomotor nerves.

Clinical relevance

Inferior MI

RCA occlusion causes ST elevation in II, III and aVF, often with bradyarrhythmia from AV nodal ischaemia.

SA nodal ischaemia

Sinus pauses and sick-sinus syndrome follow RCA disease that strangles the node's supply.

Related conditions

• Coronary artery disease
• Heart attack (myocardial infarction)