1. Division of Cardiology, Department of Internal Medicine, Samsung Changwon Hospital, Sungkyunkwan University, College of Medicine, Changwon, Korea.
2. Division of Cardiology, Department of Internal Medicine, College of Medicine, Dongguk University, Gyeongju, Korea.
3. Department of Anatomy, Dongguk Medical Institute, College of Medicine, Dongguk University, Gyeongju, Korea.