Right ventricular outflow tract obstruction by cardiac metastasis as the first manifestation of follicular thyroid carcinoma.

A 40-year-old man was sent to the echocardiographic laboratory because of a heart murmur. An intracardiac mass, causing obstruction of flow within right ventricle, was diagnosed and the patient was referred to surgery. Histologic examination classified the mass as a metastasis of highly differentiated follicular carcinoma of the thyroid gland. Thyroidectomy was performed and radioiodine treatment instituted. Thus echocardiographic identification of right ventricular outflow obstructing mass was the initial presentation of follicular carcinoma of the thyroid gland. Early detection of this moderately disseminated malignancy allowed for surgical excision and systemic radioactive iodine treatment.