^○Kanji Matsuzaki^1,2, Yusuke Iguchi¹, Toru Tsukada¹, Yasunori Watanabe¹ (1.Hitachi General Hospital, Department of Cardiovascular Surgery, 2.University of Tsukuba Hospital, Hitachi Social Cooperation Education Research Center)

^○Mitsuaki Matsumoto, Yoji Kubo, Reiko Kemmochi (Tsuyama Chuo Hospital Department of Cardiovascular Surgery)

^○Hideyuki Iwaki¹, Tomoki Chou³, Astushi Matumoto³, Hiroto Tomita¹, Fimie Saitou¹, Susumu Isoda², Munetaka Masuda³ (1.Department of cardiovascular surgery, Saiseikai Yokohamashi Nanbu Hospital, Yokohama, Japan, 2.Department of cardiovascular surgery, Fujisawa shimin hospital, 3.Department of Surgery, Yokohama City University)

^○Hikaru Uchiyama¹, Koujirou Furukawa¹, Yuuichirou Hirata¹, Tomohiro Ueda¹, Tatsuji Onzuka¹, Eiki Tayama¹, Shigeki Morita¹, Akira Shiose² (1.Kyushu Medical Center Cardiovascularsurgery, 2.Kyushu University Hospital Cardiovascularsurgery)