1. Division of Cardiology, Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Korea.
2. Division of Cardiology, Department of Internal Medicine, Kyung Hee University Medical College, Seoul, Korea.
3. Department of Cardiology, Chonnam National University Hospital, Gwangju, Korea.
4. Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.
5. Division of Cardiology, Eulji University College of Medicine, Daejeon, Korea.
6. Division of Cardiology, Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea.
7. Department of Cardiology, Ewha Woman University, Seoul, Korea.
8. Division of Cardiology, Department of Internal Medicine, Soon Chun Hyang University Hospital, Seoul, Korea.
9. Division of Cardiology, Department of Internal Medicine, Daegu Catholic University, Daegu, Korea.