Sporadic Form of Recurrent Atrial Myxoma: The Blob Strikes Back

Cardiac myxoma is a benign neoplasm composed of stellate to plump, cytologically bland mesenchymal cells set in a myxoid stroma. Although benign, as they can lead to severe complications, they are often removed surgically. A 39-year-old female presented with a chief complaint of generalized fatigue. Patient had a history of a large 7cm x 2.5cm left atrial myxoma resected at the age of 32 years after she presented with symptoms of dyspnea on exertion. The dyspnea was due to prolapse of the mass through the mitral valve during diastole, leading to functional severe mitral stenosis. The mass was resected with clear margins confirmed on biopsy. On physical examination, heart rate was regular with no murmurs. No signs of congestive heart failure were noted. A 2D echo revealed a mobile structure in the left atrium along with mild mitral regurgitation. Cardiac MRI showed a 21mm x 9mm well defined, pedunculated, mobile mass in the left atrium arising from inter-atrial septum. The mass was hyperintense on T2 weighted images with patchy delayed hyper-enhancement consistent with recurrence of a myxoma. The patient underwent a repeat median sternotomy with the removal of left atrial mass and repair of atrial septum with hemashield patch. The mass was sent for pathological evaluation confirming the diagnosis of recurrent myxoma. On genetic testing, patient tested negative for mutations in PRKAR1A gene (mutated in up to 60%-80% cases with Carney complex), MEN1, RET and sarcoma (TP53) genes. Cardiac myxomas are rare primary benign tumors of the heart with a small recurrence rate. Follow-up studies have rarely reported recurrences after complete resection. However, in our case not only did the patient have the sporadic form of myxoma with recurrence, but it also occurred within three years of the previous resection despite complete removal with clear margins.