Coronary arterial supply dictates specific myocardial territories. By convention, coronary dominance is determined by whichever artery supplies the posterior descending artery (PDA) — most commonly the right coronary artery (~85% of the population).
| Vessel | Territory |
|---|---|
| Left Anterior Descending (LAD) | Anterior wall · anteroseptal wall · the true cardiac apex |
| Left Circumflex (LCx) | Lateral wall of the left ventricle |
| Right Coronary Artery (RCA) | Inferior wall · inferoseptal wall |
When reviewing wall-motion abnormalities, map the affected segments back to the supplying vessel to predict the culprit lesion before you start scrolling through the angiogram.