Exercise-induced myocardial ischemia in a patient with dislocated right coronary artery orifice in the right sinus of Valsalva.

Anomalous origin of the right coronary artery (RCA) is a rare congenital anomaly, which may cause myocardial ischemia and sudden death. In most cases, the RCA orifice is located in the left sinus of Valsalva and the RCA courses between the great arteries. We report a case in whom the RCA orifice is located in the right sinus of Valsalva but myocardial ischemia in the territory of the RCA was induced by exercise. Multidetector-row computed tomography showed that the RCA orifice was located in the right sinus of Valsalva adjacent to the left sinus of Valsalva and the RCA coursed between the great arteries. Compression of the RCA by the great arteries during exercise was thought to be the major cause of myocardial ischemia.