Cardiac actinomycosis: an unusual cause of an intracardiac mass.

Actinomycosis is a chronic disease characterized by abscess formation, tissue fibrosis, and draining sinuses that may involve the cervicofacial area, thorax, abdominopelvic region, or central nervous system. We describe a patient with cardiac actinomycosis presenting with pericardial disease and an intracardiac mass. The diagnosis failed to be obtained by pericardiocentesis, but was obtained after echocardiographically guided biopsy of the intracardiac mass. The patient recovered with long-term penicillin therapy. A review of the literature highlights the frequent pericardial presentation of cardiac actinomycosis, the potential difficulty in making the diagnosis, and the remarkable clinical response and good prognosis that can result when the correct diagnosis is made and appropriate antibiotic therapy administered.