Cardiovascular & Arrhythmia Center;
Chung-Ang University Hospital;
Chung-Ang University College of Medieine;
Seoul;
South Korea;
Division of Cardiology;
Kangwon National University Hospital;
Chuncheon;
South Korea;
Division of Cardiology;
Yonsei University Wonju College of Medicine;
Wonju;
South Korea;
Division of Cardiology;
College of Medicine;
Hanyang University;
Seoul;
South Korea;
Department of Cardiology;
Soonchunhyang University College of Medicine;
Seoul;
South Korea;
Department of Cardiology;
Chungnam National University Hospital Daejeon;
South Korea;
Department of Cardiology;
Korea University Guro Hospital;
Seoul;
South Korea;