1. Division of Cardiology, Gimcheon Jeil Hospital, Gimcheon, Korea.
2. Division of Cardiology, Daegu Catholic University Medical Center, Daegu, Korea.
3. Pohang St. Mary Hospital, Pohang, Korea.
4. Division of Cardiology, Dongguk University Medical Center, Gyeongju, Korea.
5. Division of Radiology, Daegu Catholic University Medical Center, Daegu, Korea.