Hyperdominant Left Anterior Descending Artery: A Rare Coronary Artery Anomaly

The posterior descending artery supplying the posterior one-third of the inter ventricular septum usually arise from the right coronary artery (RCA) or the left circumflex artery (LCx). Posterior descending artery arising from the left anterior descending artery is a rare anomaly. A 66-year man presented with chest pain, ECG changes, and raised biomarkers. A diagnosis of non-ST elevation myocardial infarction was made. Coronary angiogram, done on the next day, revealed the posterior descending artery as a continuation of the left anterior descending artery (LAD) beyond the crux and a rudimentary right coronary artery. The left anterior descending artery had subcritical stenosis in proximal course (confirmed on fractional flow reserve) and was advised medical treatment.