COMPLICATED PERICARDIAL CYST - ATYPICAL ANATOMY AND CLINICAL COURSE

Pericardial cysts are usually detected by chance and are clinically si lent in most cases. Nevertheless, symptoms and serious complications m ay occur. We describe a case of pericardial cyst diagnosed in an 8-yea r-old boy who was admitted with chest pain. Echocardiography revealed a mild to moderate pericardial effusion and a 7.5 x 5.5 cm intraperica rdial echo-free lesion consistent with a pericardial cyst. Surgery was carried out 3 days afterward because of the patient's worsening condi tion, the progressive increase of pericardial effusion, and the onset of initial signs of cardiac tamponade. The cyst showed a long and easi ly movable vascular pedicle and inflammatory areas involving the peric ardial surface. Like the pericardial effusion, the contents of the mas s appeared as serosanguineous fluid on aspiration. Histologic examinat ion confirmed the diagnosis of pericardial cyst and showed findings ac cording to ischemia-related lesions of the cyst. The coexistence of pe ricardial cyst and cardiac tamponade is very unusual. The atypical ana tomy and clinical course suggest a distinct and so far undescribed pat hogenetic mechanism for this association: the torsion of a vascular pe dicle and the subsequent development of ischemia-related lesions of th e cyst.