[1] Sungkyunkwan Univ, Sch Med, Dept Med, Heart Vasc Stroke Inst,Div Cardiol,Samsung Med Ct, Seoul, South Korea
[2] Sungkyunkwan Univ, Sch Med, Samsung Changwon Hosp, Dept Cardiol, Seoul, South Korea
[3] Yonsei Univ, Coll Med, Severance Cardiovasc Hosp, Div Cardiol, Seoul, South Korea
[4] Korea Univ, Dept Internal Med, Anam Hosp, Div Cardiol, Seoul, South Korea
[5] Ehwa Womans Univ, Sch Med, Seoul Hosp, Dept Cardiol, Seoul, South Korea
[6] Konkuk Univ, Med Ctr, Sch Med, Div Cardiol,Dept Internal Med, Seoul, South Korea
[7] Chungbuk Natl Univ, Dept Internal Med, Coll Med, Cheongju, South Korea
[8] Univ Inje, Ilsan Paik Hosp, Coll Med, Div Cardiol,Dept Internal Med, Seoul, South Korea
[9] Sejong Gen Hosp, Dept Med, Div Cardiol, Bucheon, South Korea
[10] Chung Ang Univ Hosp, Div Cardiol, Dept Med, Seoul, South Korea
[11] Chungnam Natl Univ Hosp, Dept Internal Med, Div Cardiol, Daejeon, South Korea
[12] Inha Univ Hosp, Dept Med, Div Cardiol, Incheon, South Korea
[13] Dankook Univ, Dankook Univ Hosp, Dept Internal Med, Div Cardiovasc Med,Coll Med, Cheonan, South Korea