Right coronary artery
The RCA arises from the right coronary sinus as one of only two branches from the ascending aorta.
The RCA courses to the right in the right atrioventricular groove, along the anterior surface to the inferior surface of the heart.
- In people with right dominant circulation (seen in the majority of people), the RCA turns anteriorly at the crux to become the inferior interventricular artery.
- In people with left dominant circulation the RCA peters out usually as an acute marginal artery and the inferior interventricular artery usually arises from the left circumflex artery.
- conus artery
- sinotubular artery
- acute marginal arteries
- terminal branches
- inferior interventricular artery also known as posterior descending artery (PDA)
- Posterior left ventricular branch (PLV or PLB)
Variations in origin:
- from the aorta at or above the sinotubular junction
- from the left coronary sinus or left coronary artery where the proximal RCA takes a 'malignant' inter-arterial course in which the vessel is prone to extrinsic compression
- in up to 50% of cases there are separate ostia for the RCA and conus artery 2
Variations in branching:
- PDA and PLV as terminal branches
- PDA as the only terminal branch (in which PLV is supplied by the LCx)
- Terminates as an acute marginal branch (in left dominant circulations)
Variations in course:
- intra-atrial course (figure 1)
- inter-arterial course (due to aberrant origin)
See main article: congenital coronary artery anomalies.