1. Division of Cardiology, Department of Internal Medicine, Kangwon National University School of Medicine, Chuncheon, Republic of Korea
2. Department of Cardiology, Chonnam National University Hospital, Gwangju, Republic of Korea
3. Division of Cardiology, Severance Cardiovascular Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea
4. Division of Cardiology, Inje University College of Medicine, Haeundae Paik Hospital, Busan, Republic of Korea