1. Division of Cardiology, Department of Internal Medicine, Seoul National University Hospital and Seoul National University College of Medicine , Seoul 03080 , Republic of Korea
2. Division of Cardiology, Department of Internal Medicine, Chosun University Hospital , Gwangju , Republic of Korea
3. Division of Cardiology, Department of Internal Medicine, Korea University Guro Hospital , Seoul 08308 , Republic of Korea
4. Division of Cardiology, Department of Internal Medicine, Kangnam Sacred Heart Hospital , Seoul , Republic of Korea
5. Division of Cardiology, Department of Internal Medicine, Presbyterian Medical Center , Jeonju , Republic of Korea
6. Division of Cardiology, Department of Internal Medicine, Pusan National University Yangsan Hospital , Yangsan , Republic of Korea
7. Division of Cardiology, Department of Internal Medicine, Hanyang University Hospital , Seoul , Republic of Korea
8. Division of Cardiology, Department of Internal Medicine, Hallym General Hospital , Incheon , Republic of Korea
9. Division of Cardiology, Department of Internal Medicine, Chungbuk National University , Cheongju , Republic of Korea
10. Division of Cardiology, Department of Internal Medicine, Kangwon National University , Chuncheon , Republic of Korea
11. Division of Cardiology, Department of Internal Medicine, Seoul Medical Center , Seoul , Republic of Korea
12. Division of Cardiology, Department of Internal Medicine, Soonchunyang University Cheonan Hospital , Cheonan , Republic of Korea
13. Division of Cardiology, Department of Internal Medicine, Ajou University Medical Center , Suwon , Republic of Korea
14. Division of Cardiology, Department of Internal Medicine, Dong-A University Hospital , Busan , Republic of Korea