1. Division of Cardiology, Department of Internal Medicine, Samsung Changwon Hospital, Sungkyunkwan University School of Medicine, Changwon, Korea.
2. Department of Emergency Medicine, Samsung Changwon Hospital, Sungkyunkwan University School of Medicine, Changwon, Korea.
3. Division of Cardiology, Department of Internal Medicine, Dong-A University College of Medicine, Busan, Korea.