A coronary artery bypass grafting device includes a plurality of attachment members each having: a flexible tube (102) a suction cup portion (101) provided in a tip end side of the flexible tube (102) a three-way cock (103) provided in the flexible tube (102) and a holding member (104) that holds the flexible tube (102). At least one of the attachment members further includes a duckbill valve (111) provided in the flexible tube (102).
