1. Naresuan University Hospital, Naresuan University, Division of Cardiovascular and Thoracic Surgery, Department of Surgery, Phitsanulok, Thailand
2. Buddachinaraj Hospital, Division of Cardiovascular and Thoracic Surgery, Department of Surgery, Phitsanulok, Thailand
3. King Chulalongkorn Memorial Hospital, Chulalongkorn University, Division of Cardiovascular and Thoracic Surgery, Department of Surgery, Bangkok Thailand