1. Division of Cardiology, Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Korea.
2. Division of Cardiology, Department of Internal Medicine, Ewha Womans University School of Medicine, Seoul, Korea.
3. Division of Cardiology, Department of Internal Medicine, Korea University Medical Center, Seoul, Korea.
4. Division of Cardiology, Department of Internal Medicine, Kyung Hee University School of Medicine, Seoul, Korea.
5. Division of Cardiology, Department of Internal Medicine, Sanggye Paik Hospital, Inje University College of Medicine, Seoul, Korea.
6. Division of Cardiology, Department of Internal Medicine, Bundang CHA Medical Center, CHA University, Seongnam, Korea.
7. Division of Cardiology, Department of Internal Medicine, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Korea.
8. Department of Neurology and Epilepsy Research Institute, Yonsei University College of Medicine, Seoul, Korea.
9. Department of Preventive Medicine, Yonsei University College of Medicine, Seoul, Korea.