Transesophageal echocardiography (TEE) is frequently used in the operating room to assess surgical repairs in children with congenital heart disease. Complications from the procedure are unusual, but the potential for TEE probe compression of normal and abnormal posterior vascular structures has been recognized. We report a case of TEE probe compression of an aberrant right subclavian artery in a patient undergoing repair of an atrioventricular septal defect.