Radiological reasoning: Right atrial mass.

OBJECTIVE

An older man with a history of urothelial cancer presented with an incidental right atrial mass. Cardiac MRI showed a pedunculated right atrial mass that was homogeneous and of intermediate signal intensity on T1- and T2-weighted images. No signal drop-out was seen on fat-suppressed images. The mass did not exhibit enhancement on the first-pass perfusion and delayed contrast-enhanced images.

CONCLUSION

A myxoma is the most common benign primary intracavitary cardiac mass. Although the MRI features are not pathognomonic, certain features such as location, presence of a stalk, and noninfiltrating nature may help to distinguish a myxoma from other intracavitary masses such as a thrombus, metastases, and primary cardiac malignancy. The final pathologic diagnosis was a right atrial myxoma.