An 85-year-old patient suffered from progressive deterioration (NYHA III) for several months. Cardiac disease was suspected. Echocardiography as well as a CT scan of the heart revealed a heart tumor to be the cause. Tumor staging was negative. After transvenous biopsy, the diagnosis of a Burkitt lymphoma could be established. Due to the advanced age of the patient, the intented surgical therapy was turned down and the patient was treated with 6 courses of a potentially therapeutic chemotherapy (CHOP scheme), which was well tolerated by the patient. The following CT scan showed a complete remission of the tumor. Six months after chemotherapy the patient is in NYHA stage I.