[1] Hanyang Univ, Myongji Hosp, Dept Internal Med, Div Cardiol,Coll Med, Goyang, South Korea
[2] Chung Ang Univ, Chung Ang Univ Hosp, Cardiovasc & Arrhythmia Ctr, Coll Med, Seoul, South Korea
[3] Yonsei Univ, Severance Cardiovasc Hosp, Dept Internal Med, Div Cardiol,Coll Med, Seoul, South Korea
[4] Yonsei Univ, Gangnam Severance Hosp, Dept Internal Med, Div Cardiol,Coll Med, Seoul, South Korea
[5] Chungnam Natl Univ Hosp, Dept Internal Med, Div Cardiol, Daejeon, South Korea
[6] Seoul Natl Univ, Div Cardiol, Bundang Hosp, Seongnam, South Korea
[7] Korea Univ, Dept Internal Med, Div Cardiol, Anam Hosp, Seoul, South Korea
[8] Univ Ulsan, Asan Med Ctr, Dept Internal Med, Div Cardiol,Coll Med, Seoul, South Korea
[9] Chonbuk Natl Univ Hosp, Dept Internal Med, Div Cardiol, Jeonju, South Korea
[10] Sungkyunkwan Univ, Samsung Med Ctr, Dept Med, Div Cardiol,Sch Med, Seoul, South Korea
[11] Yonsei Univ, Yongin Severance Hosp, Dept Internal Med, Div Cardiol,Coll Med, Yongin, South Korea