Right coronary artery cirsoid with fistulous connection to the coronary sinus.

A 61-yr-old woman was referred to our hospital for evaluation of a suspected right atrial myxoma. The transesophageal echocardiogram suggested the presence of an anomalous right coronary artery with fistulous connection to the coronary sinus. At cardiac catheterization, an oxygen step-up in the right atrium indicated a 1.3:1.0 left-to-right shunt. Aortic root angiography showed a large and calcified right coronary artery cirsoid draining to the coronary sinus, which appeared remarkably dilated. In this rare anomaly, cardiac catheterization is necessary, not only to quantify the magnitude of the left-to-right shunt, which is an important requirement for the indication to surgical treatment, but also to confirm the echocardiographic diagnosis.