Primary cardiac sarcomas carry a dismal prognosis with no known curative therapy using standard treatment approaches. By its very location, the possibility of a radical complete resection—the underlying principle in the management of any soft-tissue sarcoma—is precluded. While literally in a continuous "blood bath," cardiac sarcomas are associated with a very high rate of hematogenous metastases. This report describes the management of a case in a 51-year-old white man with a high-grade unresectable cardiac sarcoma who was treated with hyperfractionated (twice daily) radiotherapy to a total dose of 7,050 cGy along with a radiosensitizer, (5'-iododeoxyuridine. The patient currently is disease-free and functioning well more than 5 years following this novel treatment approach.