Radioiodide imaging of struma cordis.

This is the first reported case in which struma cordis was demonstrated with radionuclide imaging. A 56-year-old white woman underwent surgical excision of a benign intracardiac thyroid mass (struma cordis). Subsequent radionuclide imaging with I-123 sodium iodide and Tc-99m labeled red blood cells demonstrated a normal cervical thyroid gland as well as a focus of activity in the mediastinum consistent with intracardiac thyroid.