Cardiac metastasis from epithelial thyroid cancer is a very rare and potentially serious complication. We have identified only 54 reported cases over a 130-year period. Here we review this literature. Cardiac metastases are frequently asymptomatic, but when symptoms develop these tend to be severe and often fatal. The prognosis of cardiac metastases from thyroid cancer is unclear as survival data are often missing or absent in reported cases. However, as many patients died suddenly from cardiac complications, the prognosis seems poor. Of those patients who survived, all underwent surgical intervention. Trans-thoracic echocardiography is the diagnostic modality of choice as it allows dynamic evaluation of intracardiac masses. Metastatic involvement of the heart from thyroid cancer is uncommon. Left untreated this complication seems likely to be fatal. Therefore, in patients with established thyroid malignancy who develop cardiac arrhythmias, new murmurs, or signs of cardiac decompensation, we suggest that cardiac metastases be considered. Echocardiography should be performed in patients with advanced thyroid cancer and cardiac symptoms or signs. If a cardiac metastasis is present, we recommend surgical intervention if possible.