[Intracardiac ectopic thyroid: a report of a clinical case with a long-term follow-up].

We describe the prolonged follow-up of a 64-year-old female patient, with an ectopic intracardiac thyroid gland. The mass was first detected 14 years ago, during a routine echocardiographic examination. The patient suffered from episodes of palpitation and cardiac auscultation revealed a systolic murmur. At cardiac surgery a right ventricular mass penetrating most of the interventricular septum was found. The mass was also prolapsing into the pulmonary infundibulum and could not be removed. On histopathology examination, the presence of a normal tissue was demonstrated. Two main clinical events characterized the prolonged follow-up: the gradual development of a massive tricuspid insufficiency, probably due to the strict anatomic relationship between the septal tricuspid papillary muscle and the mass itself; frequent supraventricular arrhythmias, partially refractory to different pharmacologic regimens, which could be ascribed to the chronic overload of the right atrium. The mass size has been stable over the years, and no thyroid hormone derangement was ever found.