Single coronary ostium in right aortic sinus without other major cardiovascular abnormalities presenting as angina pectoris in an adult- a rare anatomical variant

Anomalous origin of coronary arteries represents a clinical challenge because of the anatomical variability, possible functional consequences and the lack of large published series. We report a 48 yr old diabetic female who presented with chest pain for 6 months. Her ECG, 2D Echo and TMT were normal. Coronary angiogram was done in view of persistent symptoms and diabetes which showed single coronary ostium in the right aortic sinus with anomalous origin of LMCA from proximal superdominant RCA. Epicardial coronaries were normal. CT coronary angiogram was done to evaluate the course of anomalous LMCA, which showed prepulmonic course excluding any extrinsic compression. What makes this case unusual is that; single coronary ostium without other major cardiovascular abnormalities in itself is a rare entity. To our knowledge, the anatomical subtype of our patient according to Shirani J et al classification of "solitary coronary ostium in aorta" is a rare subtype. In view of presentation at this age, prepulmonic course of LMCA, this anomaly was thought to be benign and she was advised medical management. Cause of angina in our patient could be multifactorial like microvascular angina, coronary spasm or exercise induced ischemia in the usual LCX territory as reported in patients with super dominant RCA. This case demonstrates the importance of evaluating young individuals with chest pain, since sudden death can occur with an anomalous coronary.