1. Departments of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
2. Department of Cardiology, Heart Institute, Asan Medical Center, University of Ulsan College of Medicine, 86 Asanbyeongwon-gil, Seoul 138-736, Korea
3. Clinical Epidemiology and Biostatistics, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
4. Department of Radiology, Ulsan University Hospital, University of Ulsan College of Medicine, Seoul, Korea
5. Department of Cardiology, Ulsan University Hospital, University of Ulsan College of Medicine, Seoul, Korea