Despite the rarity of primary malignant tumors of the heart (0.0017 to 0.03% of large postmortem series) and the infrequency of clinical signs and symptoms (0 to 50%) of the more common metastatic cardiac tumors, many cardiothoracic surgeons at some time will encounter a patient with one of these two conditions. A review of the medical literature yielded 28 cases of primary cardiac tumors, 10 of secondary tumors, and 12 of carcinoid heart disease treated surgically and followed sufficiently for retrospective evaluation. We summarized those cases and made the following conclusions. Primary malignant tumors of the heart are occasionally resectable, although cure is unlikely; survival may be enhanced by postoperative irradiation but probably not by postoperative chemotherapy. For patients with secondary malignant tumors of the heart, surgical intervention is rarely of benefit except for establishing a tissue diagnosis, effecting artificial cardiac pacing, decompressing symptomatic pericardial effusions, or reducing an obstructive tumor mass. Patients with carcinoid heart disease affecting the valves may derive benefit from valve replacement or repair. Thus, in selected patients with malignant cardiac disease, surgical intervention may be feasible and should always be among the therapeutic options considered.