1. Department of Internal Medicine, Division of Cardiology, Hanyang University Seoul Hospital, Hanyang University College of Medicine, Seoul, Republic of Korea
2. Division of Cardiology, Department of Internal Medicine, Hanyang University Guri Hospital, Hanyang University College of Medicine, Guri, Republic of Korea
3. Department of Biostatistics, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea