RESUMO
Calcified amorphous tumor (CAT) of the heart is a rare nonneoplastic cardiac mass that may exhibit symptoms resembling malignancy. In this report, we presented a 4-month-old male baby with repeated attacks of cyanosis and a cardiac murmur. Echocardiography revealed a tumoral noncircumscribed mass in the right atrium adhering to the interatrial septum which extends to the inferior vena cava. Cardiac exploration was carried out to excise the tumor. A histopathological study demonstrated the presence of thrombus-like tissue with extensive calcification and foreign body type giant cell reactions. After operation, the patient had an uneventful hospitalization. Although CAT is mainly diagnosed in adult patients, it should be considered in the causes of cardiac mass in the neonatal period.