Acute tamponade in a newborn infant caused by a massive cystic teratoma.

Accepted for publication 3 January 1996 A female infant of 3500 g born at term presented with bradycardia, respiratory distress, and severe metabolic acidosis. Polyhydramnios had been noted at 15 weeks' gestation but no fetal abnormality was detected at that stage. The rest of the pregnancy was uneventful. Echocardiography showed a large collection of pericardial fluid and a giant multicystic mass within the pericardium. The tumour appeared larger than the heart itself and was attached to the anterior aspect of the ascending aorta (fig 1). At thoracotomy a large cystic tumour occupying most of the pericardial space was found. Serous fluid (200 ml) was removed from the intrapericardial space, and myocardial function rapidly improved. The mass was dissected off the aorta and was completely removed. Histological study of the mass revealed a mature cystic teratoma measuring 6 x 5.5 x 2 8 cm. The cysts, 0 3 cm to 1 cm diameter, were lined by mucus-secreting epithelium of the respiratory type (fig 2). The patient remained symptom free with no signs of tumour recurrence at follow up five months later. Teratomas are usually benign tumours in childhood. They are often cystic, most commonly located in the pericardium, and may be attached to the ascending aorta.' Clinical manifestations of benign pericardial teratomas tend to be secondary to the degree of pericardial effusion. This occurs when cysts within the tumour rupture or when lymphatic Figure 2 Macroscopic appearance of the cystic mass. Bar = 1 cm.