The coronary arteries supply oxygenated blood to the myocardium. Understanding their branching patterns and territories is essential for PA students preparing for exams or for understanding cardiac specimens in autopsy service.
Right Coronary Artery (RCA)
Supplies:
- Entire free wall of the right ventricle
- SA node
- AV node
- Posterior 1/3 of the interventricular septum (in right-dominant hearts)
The RCA courses along the right AV groove and typically gives rise to the Posterior Descending Artery (PDA) in most individuals.
Left Coronary Artery (LCA)
Quickly divides into:
Left Anterior Descending (LAD)
Supplies:
- Anterior left ventricular wall
- Apex of the heart
- Anterior 2/3 of the interventricular septum
This is the classic “widowmaker” artery.
Left Circumflex (LCx)
Supplies:
- Lateral left ventricular wall
- Posterior wall of left ventricle + posterior 1/3 of ventricular septum (in left-dominant hearts)
Why Coronary Territory Matters
Understanding supply territories helps you:
- Understand and predict infarct patterns
- Prepare for cardiac autopsy cases
- Improve exam performance
Knowing this is foundational for understanding ischemic heart disease.