Heart Failure Resulting from Giant Left Atrial Synovial Sarcoma Metastasis

Synovial sarcoma metastasis affecting the heart and infiltrating the mitral valve is a very rare pathology. We report the case of a 44-year-old male treated with chemotherapy for atypical synovial sarcoma of the oral mucosa who presented to our clinic after cardiac decompensation with a presumptive diagnosis of myxoma of the left atrium. A large necrotic tumour positive for CK 22, EMA, CD 99 and BCL-2 but negative for translocation in COBRA-FISH analysis by break-apart probe could be excised and revealed a very rare subtype of synovial sarcoma metastasis arising from the endocard of the left atrium. The tumour was resected and the mitral valve reconstructed through ring annuloplasty.