A 55-year-old man came with progressive exertional dyspnea, palpitations, and two episodes of syncope over the past month. Cardiovascular examination revealed a mid-diastolic murmur best heard at the apex.
Contrast-enhanced CT scan of the chest shows a well-defined, lobulated soft tissue mass in the left atrium, measuring approximately 3.5 × 3.2 cm, arising from the interatrial septum near the fossa ovalis. The lesion projects into the mitral inflow tract, with partial prolapse toward the mitral valve. Punctate calcific foci are noted in the lesion, suggestive of chronicity. There is dilatation of both the left and the right atrium. There is no pericardial effusion.