[1] Cardiovascular & Arrhythmia Center, Chung-Ang University Hospital, Chung-Ang University College of Medicine
[2] Division of Cardiology, Kangwon National University, Hospital
[3] Division of Cardiology, Yonsei University Wonju College of Medicine
[4] Division of Cardiology, College of Medicine, Hanyang University
[5] Department of Cardiology, Soonchunhyang University, College of Medicine
[6] Department of Cardiology, Chungnam National University Hospital
[7] Department of Cardiology, Korea University Guro