1. Division of Cardiology, Department of Medicine, Cardiovascular and Stroke Imaging Center, Heart Vascular and Stroke Institute, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
2. Division of Cardiovascular Diseases, Mayo Clinic College of Medicine, Rochester, Minnesota, USA.
3. Division of Cardiovascular Diseases, Mayo Clinic College of Medicine, Jacksonville, Florida, USA.
4. Department of Radiology, Cardiovascular and Stroke Imaging Center, Heart Vascular and Stroke Institute, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.