CT diagnosis of isolated anomalous origin of the RCA arising from the main pulmonary artery.

Anomalies of the coronary arteries can be benign or life threatening. The prevalence of these anomalies is reported to be approximately 0.3% to 1%, however, this may be an underestimation as conventional angiography may not allow correct identification of these abnormalities. Morphologic variations can arise in the origin, course, or termination of coronary arteries. These variations may be related to other congenital abnormalities or isolated. Some anomalies can lead to myocardial ischemia and have been implicated in episodes of sudden death in young adults. Noninvasive imaging modalities such as multidetector computerized tomography provide an efficient method of evaluating coronary artery anomalies by allowing more complete visualization of chest, mediastinal, and vascular structures. We describe a case of anomalous origin of the right coronary artery originating from the main pulmonary trunk demonstrated by computerized tomography in a patient with exertional ischemia. In the past, this diagnosis has only been made by angiography, echocardiography, and at autopsy.