1. Department of Thoracic and Cardiovascular Surgery, Seoul National University Bundang Hospital, Seoul, Korea
2. Department of Thoracic and Cardiovascular Surgery, College of Medicine, Seoul National University, Seoul, Korea
3. Department of Thoracic and Cardiovascular Surgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
4. Department of Thoracic and Cardiovascular Surgery, Daegu-Fatima Hospital, Daegu, Korea
5. Department of Thoracic and Cardiovascular Surgery, Severance Hospital, Yonsei University College of Medicine, Seoul, Korea
6. Department of Thoracic and Cardiovascular Surgery, College of Medicine, Dankook University, Yongin, Korea
7. Department of Thoracic and Cardiovascular Surgery, Catholic University of Korea, St. Vincent’s Hospital, Suwon, Korea