1. Cardiology Division, Department of Internal Medicine, Kangnam Sacred Heart Hospital, Hallym University College of Medicine, Seoul, Korea.
2. Department of Internal Medicine, Seoul National University College of Medicine and Department of Cardiology, Seoul National University Bundang Hospital, Seongnam, Korea.
3. Severance Cardiovascular Hospital, Yonsei University College of Medicine, Seoul, Korea.
4. Department of Cardiology, Cardiovascular Center, Korea University Anam Hospital, Korea University College of Medicine, Seoul, Korea.
5. Division of Cardiology, Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Korea.
6. Department of Internal Medicine, Gyeongsang National University School of Medicine and Gyeongsang National University Hospital, Jinju, Korea.
7. Division of Cardiology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
8. Department of Cardiology, Yonsei University Wonju Severance Christian Hospital, Wonju, Korea.
9. Division of Cardiology, Chung-Ang University Gwangmyeong Hospital, Gwangmyeong and Department of Internal Medicine, Chung-Ang University College of Medicine, Seoul, Korea.
10. Division of Cardiology, Department of Internal Medicine, Kangwon National University College of Medicine, Kangwon National University School of Medicine, Chuncheon, Korea.
11. Department of Internal Medicine and Cardiovascular Center, Seoul National University Hospital, Seoul, Korea.
12. Department of Cardiology, Dong-A University Hospital, Busan, Korea.
13. Division of Cardiology, Ulsan University Hospital, University of Ulsan College of Medicine, Ulsan, Korea.