1. Department of Thoracic and Cardiovascular Surgery, Biomedical Research Institute, Pusan National University School of Medicine, Busan, Korea
2. Department of Anesthesia and Pain Medicine, Pusan National University Hospital, Pusan National University School of Medicine, Busan, Korea
3. Department of Thoracic and Cardiovascular Surgery, Jeju National University Hospital, Jeju National University School of Medicine, Jeju, Korea