1. Department of Emergency Medicine, Gachon University Gil Hospital, Incheon, Korea.
2. Department of Cardiovascular Surgery, Gachon University Gil Hospital, Incheon, Korea.
3. Department of Emergency Medicine, Seoul Metropolitan Boramae Hospital, Seoul, Korea.
4. Department of Emergency Medicine, Dongguk University Hospital, Goyang, Korea.
5. Department of Emergency Medicine, Pusan National University Hospital, Busan, Korea.