1. Division of Cardiology, Department of Internal Medicine, Inje University College of Medicine, Seoul Paik Hospital, Seoul, Korea.
2. Division of Cardiology, Department of Internal Medicine, Inje University College of Medicine, Ilsan Paik Hospital, Goyang, Korea.
3. Division of Cardiology, Department of Internal Medicine, Chuncheon Sacred Heart Hospital, Hallym University, Chuncheon, Korea.
4. Division of Cardiology, Department of Internal Medicine, Gyeongsang National University Changwon Hospital, Changwon, Korea.
5. Division of Cardiology, Department of Internal Medicine, Heart Vascular Stroke Institute, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.