Cardiac tamponade caused by a mediastinal teratoma.

Mediastinal masses in children younger than 2 years often cause symptoms from tracheal compression, but clinical indications later in childhood are less frequent. Mediastinal teratomata arise in the anterior region, and when they produce symptoms these are usually manifestations of tracheal compression, pain, pleural perforation or secondary infection of the tumour. Pericardial perforation is a rare and life-threatening complication. A case of sudden pericardial perforation and cardiac tamponade caused by a mediastinal teratoma is described.