A 70-year-old woman, who was taking prednisolone to treat Takayasu arteritis, underwent surgery for aortic regurgitation and aneurysm of the ascending aorta. The probe of the transesophageal echocardiography (TEE) could not be inserted due to resistance during anesthesia induction and was inserted after starting cardiopulmonary bypass. The right pneumothorax was observed during surgery. After surgery, fever and a high C-reactive protein level continued, and a computed tomography (CT) examination revealed right thoracic empyema together with free air around the esophagus. The esophageal perforation diagnosis was confirmed by upper endoscopy. Esophageal leakage continued despite emergency esophageal repair and enterostomy. Although esophagectomy was performed 2 months later, the patient died 6 months after cardiac surgery due to sepsis. Thus, esophageal perforation related to TEE in open-heart surgery was considered to be associated with a poor prognosis.