Incidentally Detected Mediastinal Mass by Transesophageal Echocardiography in a Patient With Severe Mitral Stenosis.

A mediastinal mass can be incidentally detected during transesophageal echocardiography, so clinicians performing this procedure should be aware of this possibility and able to interpret related echocardiographic findings. In evaluating a 69-year-old man with dyspnea, mitral stenosis was identified on transthoracic echocardiography. Subsequently, during transesophageal echocardiography, a mediastinal mass in the posterior mediastinum was observed. The computed tomography scan confirmed the transesophageal echocardiography findings and suggested that lymphoma and metastatic malignancy should be considered in the differential diagnosis.