1. Cardiology Division, Kangnam Sacred Heart Hospital, Hallym University College of Medicine, Seoul, Korea.
2. Cardiology Division, Severance Cardiovascular Hospital, Yonsei University College of Medicine, Seoul, Korea.
3. Cardiology Division, Seoul St. Mary's Hospital, The Catholic University College of Medicine, Seoul, Korea.
4. Cardiology Division, Kyungpook National University Hospital, Daegu, Korea.
5. Cardiology Division, Ajou University Medical Center, Suwon, Korea.
6. Cardiovascular Center, Korea University Anam Hospital, Seoul, Korea.
7. Cardiology Division, National Health Insurance Coperation Ilsan Hospital, Goyang, Korea.
8. Cardiovascular Center, Seoul National University Bundang Hospital, Seongnam, Korea.
9. Department of Cardiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
10. Cardiology Division, Wonju Christian Hospital, Yonsei University Wonju College of Medicine, Wonju, Korea.
11. Cardiology Division, Chonnam National University Hospital, Gwangju, Korea.