Pericardial cyst simulating intracardiac mass

Although pericardial celomic or mesothelial cysts are infrequent mediastinal lesions, they represent the most common benign mass lesion of the pericardium. Most often they are located at the right cardiophrenic junction. As a rule, they are asymptomatic and are discovered incidentally on routine chest radiography. A symptomatic pericardial cyst is described in a patient with congestive cardiomyopathy, causing progressive atypical chest pain, dyspnea, and palpitation. On computer tomography (CT) and other imaging methods, the lesion simulated a cardiac mass. Thoracotomy revealed a large hemorrhagic pericardial celomic cyst compressing and displacing the heart and midmediastinal vasculature.