1. Department of Internal Medicine; Seoul National University College of Medicine, Seoul National University Bundang Hospital; Seongnam Korea
2. the Medical Research Collaborating Centre; Seoul National University Bundang Hospital; Seongnam Korea
3. Division of Cardiology; Yonsei University Wonju Severance Christian Hospital; Wonju Korea
4. Division of Cardiology; Yonsei University Severance Hospital; Seoul Korea
5. Department of Internal Medicine; University of Ulsan College of Medicine, Asan Medical Centre; Seoul Korea
6. Department of Internal Medicine; The Catholic University of Korea, Seoul St Mary's Hospital; Seoul Korea
7. Department of Internal Medicine; Chungbuk National University College of Medicine; Cheongju Korea
8. Department of Internal Medicine; Sungkyunkwan University College of Medicine, Samsung Medical Centre; Seoul Korea
9. Department of Internal Medicine; Kyungpook National University College of Medicine; Daegu Korea
10. Department of Internal Medicine; Konkuk University Medical Centre; Seoul Korea
11. Department of Internal Medicine; Seoul National University College of Medicine, Seoul National University Hospital; Seoul Korea