1. Sanbon Hospital, Wonkwang University College of Medicine, Gunpo, Korea.
2. Division of Cardiology, Severance Cardiovascular Hospital, Yonsei University College of Medicine, Seoul, Korea.
3. Cardiovascular Research Institute, Yonsei University College of Medicine, Seoul, Korea.
4. Severance Biomedical Science Institute, Yonsei University College of Medicine, Seoul, Korea.