1. Department of Thoracic and Cardiovascular Surgery, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea
2. Department of Thoracic and Cardiovascular Surgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
3. Department of Thoracic and Cardiovascular Surgery, Severance Hospital, Yonsei University College of Medicine, Seoul, Korea
4. Department of Thoracic and Cardiovascular Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
5. Department of Thoracic and Cardiovascular Surgery, Pusan National University Yangsan Hospital, Yangsan, Korea
6. Department of Thoracic and Cardiovascular Surgery, CHA Bundang Medical Center, Seongnam, Korea
7. Department of Thoracic and Cardiovascular Surgery, Wonju Severance Christian Hospital, Wonju, Korea
8. Department of Thoracic and Cardiovascular Surgery, Bucheon Sejong Hospital, Bucheon, Korea
9. Department of Thoracic and Cardiovascular Surgery, Inje University Ilsan Paik Hospital, Goyang, Korea
10. Department of Thoracic and Cardiovascular Surgery, Cardiovascular Center, Keimyung University Dongsan Hospital, Keimyung University College of Medicine, Daegu, Korea
11. Department of Thoracic and Cardiovascular Surgery, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, Korea