1. Tepecik Training and Research Hospital, Department of Cardiovascular Surgery, Izmir 35180, Turkey
2. Bakirkoy Dr. Sadi Konuk Training and Research Hospital, Department of Cardiovascular Surgery, Istanbul 34147, Turkey
3. Gulhane Training and Research Hospital, Department of Cardiovascular Surgery, Ankara 06010, Turkey
4. Hacettepe University Faculty of Medicine, Department of Cardiovascular Surgery, Ankara 06230, Turkey