Right to left intracardiac shunt: a unique presentation of metastatic cardiac disease.

A 54 year old man presented with signs and symptoms of severe hypoxemia. He had a history of a nasopharyngeal epidermoid carcinoma that was thought to have been totally eradicated 2 years earlier. He was found to have a right to left interatrial shunt through a patent foramen ovale due to tricuspid valve obstruction by a solitary cardiac metastasis. No other such reported case of a metastatic cardiac lesion could be found.