Abstract
A rare case of epicardial cyst is reported. A 77-year-old man with no complaints was diagnosed with early gastric cancer. A preoperative chest CT scan incidentally revealed a cystic lesion located in the anterior mediastinum. Video-assisted thoracoscopic surgery was performed. Bloody pericardial effusion was observed. A large cystic lesion was found to extend from the anterior wall of the right ventricle. The cyst was fenestrated and bloody fluid contents were drained, followed by excision of its wall. Pathological examination showed the cyst to be lined by a single layer of mesothelial cells. A diagnosis of epicardial cyst was made. The bloody pericardial effusion suggested the possibility of subclinical rupture of the epicardial cyst.
