Clostridium perfringens within intracardiac thrombus: a case of intracardiac gas gangrene.

A70-year-old man with ischemic dilated cardiomyopathy and a known right atrial mass, presumed to be thrombus, presented to the hospital with 3 weeks of fevers and chills. One year before this admission, transesophageal echocardiography had demonstrated a 333-cm mass in the right atrium, extending into the superior vena cava (Figure, panel a). The mass was contiguous with the tip of a Groshong catheter, which was used for home dobutamine infusion. Because of a high operative risk at that time, the patient had declined surgical resection of the right atrial mass. During the present hospital admission, the Groshong catheter was removed after 4 of 6 blood cultures grew Clostridium perfringens. The presumed source of the bacteremia was the patient’s oropharynx, because he had extremely poor dentition. Repeat transesophageal echocardiography demonstrated increased size of the mass with loss of echoes centrally and extensive shadowing posteriorly (panel b). CT of the chest revealed a gas-filled mass in the right atrium, occluding the superior vena cava and extending into the right brachiocephalic vein (panel c). Given the presence of bacteremia with a known gasproducing organism, it is likely that the thrombus was infected with C perfringens. Considering the extensive nature of the thrombus and the patient’s underlying cardiomyopathy, surgical treatment was not feasible, and the patient was placed on long-term antibiotic therapy with penicillin and metronidazole. To the best of our knowledge, this is the first reported case of such a lesion.