1. Division of Cardiology, Yonsei University College of Medicine, Seoul, Korea.
2. Department of Cardiology, School of Medicine, Ewha Womans University, Seoul, Korea.
3. Department of Mechanical Engineering, Dankook University, Yongin, Korea.
4. Department of Otorhinolaryngology, Head and Neck Surgery, Inha University College of Medicine, Incheon, Korea.
5. Department of Preventive Medicine, Yonsei University College of Medicine, Yonsei University, Seoul, Korea.
6. Department of Cardiology, CHA Bundang Medical Center, CHA University, Seongnam, Korea.
7. The Division of Cardiology, Saint Carollo Hospital, Suncheon, Korea.