CASE REPORT Right Atrial Myxoma: Unusual Clinical Presentation and Atypical Glandular Histology

SUMMARY A 57-year-old black female presented with a 1-month history of right-sided congestive heart failure and clinical evidence of pulmonic and tricuspid valvular stenosis and insufficiency. The echocar-diographic examination and ventriculography demonstrated a large right atrial tumor interfering with the function of both right-sided valves. The patient underwent successful surgical resection of the tumor. Histologically, the tumor had cellular areas typical of myxoma, as well as glandular areas, a feature which has been described very rarely in this lesion. Electron microscopy of the glandular zones, which has never been reported previously, showed cells having essential homology with the usual myxoma elements. The atypical histopathology of this lesion supports the theory that atrial myxomas are true neoplasms, and are not derived from unusually organized mural thrombi. ATRIAL MYXOMAS ARE UNCOMMON but often curable tumors that may produce atypical car-diac symptoms. Approximately one-fourth of myx-omas are right-sided, and the majority of patients with these lesions have right-sided congestive heart failure.' These tumors can now be diagnosed with reasonabl