Role of cardiovascular magnetic resonance in an adolescent with a giant intrapericardial mass.

A 14 -year-old boy presented with chest pain and breathlessness. Echocardiography showed a large pericardial effusion with cardiac tamponade features and suspicion of cardiac mass. Cardiovascular magnetic resonance demonstrated a large, well-defined pericardial mass, suggesting atypical large coronary fistula with pericardial haematoma or primary cardiac/pericardial tumour such as angiosarcoma. Histology confirmed a mixed-type vascular malformation. Sirolimus therapy was initiated.