1. Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
2. Division of Cardiology, Department of Internal Medicine, Chungbuk National University Hospital, Chungbuk National University College of Medicine, Cheongju, Korea.
3. Department of Cardiology, Cardiovascular Center, Korea University Guro Hospital, Seoul, Korea.
4. Division of Cardiology, Hallym University Kangdong Sacred Heart Hospital, Hallym University College of Medicine, Seoul, Korea.
5. Division of Cardiology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
6. Department of Internal Medicine, Cardiovascular Center, Seoul National University Bundang Hospital, Seongnam, Korea.
7. Division of Cardiology, Department of Internal Medicine, Gachon University Gil Medical Center, Incheon, Korea.
8. Division of Cardiology, Department of Internal Medicine, Yonsei University Wonju College of Medicine, Wonju, Korea.
9. Division of Cardiology, Hallym University Dongtan Sacred Heart Hospital, Hallym University College of Medicine, Hwaseong, Korea.
10. Department of Internal Medicine, Seoul National University Hospital, Seoul, Korea.
11. Department of Cardiology, Bucheon St. Mary's Hospital, The Catholic University of Korea, Bucheon, Korea.
12. Division of Cardiology, Department of Internal Medicine, Kyungpook National University Hospital, Daegu, Korea.
13. Division of Cardiology, Hallym University Pyeongchon Sacred Heart Hospital, Hallym University College of Medicine, Anyang, Korea.
14. Department of Cardiovascular Medicine, Chonnam National University Hospital, Gwangju, Korea.
15. Division of Cardiology, Hallym University Kangnam Sacred Heart Hospital, Hallym University College of Medicine, Seoul, Korea.