Rare Occurrence of Myxoma in Heart Transplant Recipient: A Case Report.

BACKGROUND Cardiac myxomas are the most common primary cardiac tumors in the general population but are exceedingly rare in orthotopic heart transplant recipients. Fewer than 5 cases have been reported. Their pathogenesis in the setting of chronic immunosuppression remains unclear. CASE REPORT A 57-year-old woman with end-stage heart failure due to coronary artery disease underwent an orthotopic heart transplant in August 2017 with use of the bicaval technique. Her postoperative course included immunosuppressive therapy with tacrolimus, mycophenolate mofetil, and prednisone, with 2 episodes of moderate rejection during the early post-transplant period. Early echocardiograms revealed no abnormalities. At a routine follow-up in May 2022, she was asymptomatic; however, transthoracic echocardiography detected a mobile left atrial mass attached to the interatrial septum. Transesophageal echocardiography confirmed a nodular lesion in the left atrium, measuring 1.6×2.4 cm, located in the region of the fossa ovalis. Cardiac computed tomography demonstrated a 2.5×1.6×1.5 cm contrast-enhancing lesion consistent with myxoma. The patient underwent surgical excision under extracorporeal circulation, including partial septal resection. Histopathology confirmed the diagnosis of myxoma. DNA profiling was inconclusive regarding donor or recipient origin. At 1-year follow-up, the patient remained asymptomatic, with preserved graft function and no recurrence. CONCLUSIONS This is the fourth reported case of myxoma developing in a transplanted heart. The case emphasizes the importance of vigilant long-term echocardiographic surveillance in heart transplant recipients and raises questions regarding the potential role of immunosuppression in benign cardiac tumorigenesis.