Acute STEMI in a single coronary artery type R-III: Focus on diagnosis and treatment of a rare variant

A 61 year-old-man on treatment for type II diabetes mellitus presented to the emergency with rest angina. Electrocardiogram and troponin T were suggestive of an acute inferior wall myocardial infarction and the patient was taken up for primary percutaneous intervention (PCI) immediately. When the ostium of the left coronary artery couldn't be located on angiogram, aortography was done and revealed a common trunk arising from the right coronal sinus giving rise to the right coronary artery, an anomalous left coronary artery and an anomalous left circumflex artery. The anomalous branches were however not the culprit artery and the thrombus in the mid RCA responsible for the myocardial infarction was stented. MDCT done later proved the coronary artery anomaly to be of Type RIII with a dangerous inter-arterial course of the left anterior descending. The case report discussed the diagnostic modalities for accurate diagnosis and management options for this variant.