Single right coronary artery-R-I subtype: a report of an extremely rare case.

A single coronary ostium with no associated congenital cardiac disease is a rare congenital coronary-artery anomaly. However, a single right coronary artery has a much rarer incidence. We report here the antemortem diagnosis of a case with R-I subtype single coronary artery supplying the entire myocardium. A 36-year-old female with chest pain and dyspnea on exertion was admitted to the hospital, whose coronary angiography revealed a single, large coronary artery originating in the right aortic sinus. No observable change was detected in her electrocardiogram and her angiographic examination did not reveal any significant luminal narrowing although she experienced chest pain and dyspnea on exertion. R-I type of single coronary artery is an anomaly with a very rare incidence, which may cause myocardial ischemia and sudden death and whose recognition might be of use to physicians when diagnosing and treating this anomaly.