1 Division of Cardiology, Department of Medicine, Gyeongsang National University Hospital, Gyeongsang National University School of Medicine, Jinju, South Korea.
2 Division of Cardiology, Department of Medicine, University of California, Irvine Medical Center, Orange, California, USA.
3 Division of Cardiology, Department of Internal Medicine, Chung-Ang University Gwangmyeong Hospital, Chung-Ang University College of Medicine, Gwangmyeong, South Korea.