1. Division of Cardiology, Department of Internal Medicine, Myongji Hospital, Hanyang University College of Medicine, Goyang, Korea.
2. Cardiovascular & Arrhythmia Center, Chung-Ang University Hospital, Chung-Ang University College of Medicine, Seoul, Korea.
3. Division of Cardiology, Department of Internal Medicine, Severance Cardiovascular Hospital, Yonsei University College of Medicine, Seoul, Korea.
4. Division of Cardiology, Department of Internal Medicine, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Korea.
5. Division of Cardiology, Department of Internal Medicine, Chungnam National University Hospital, Daejeon, Korea.
6. Division of Cardiology, Seoul National University Bundang Hospital, Seongnam, Korea.
7. Division of Cardiology, Department of Internal Medicine, Korea University Anam Hospital, Seoul, Korea.
8. Division of Cardiology, Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
9. Division of Cardiology, Department of Internal Medicine, Chonbuk National University Hospital, Jeonju, Korea.
10. Division of Cardiology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
11. Division of Cardiology, Department of Internal Medicine, Yongin Severance Hospital, Yonsei University College of Medicine, Yongin, Korea.