Epicardial cyst. Report of a case with successful resection.

As a result of mass-screening, a 7-year-old girl was noted to have an abnormal shadow and was subsequently diagnosed as having a pericardial cyst. During surgery, we discovered that the cyst originated from the epicardium, and only its free wall was resected with the cyst left open to the pericardial cavity. The postoperative course was uneventful. This is presumed to be the first case of epicardial cyst ever reported in Japan. In diagnosing the epicardial cyst, the use of chest films, echocardiography and computed tomography assist angiography in making a differential diagnosis from intracardiac lesion. In treatment, surgical resection is advised. Even though the cyst may be asymptomatic, the possible compression on the surrounding organs and possible rupture into the pericardial cavity must be avoided.