I a (12), the catheter (14), and a fixation device (10) catheter set. Fixation device (10), the first protrusion provided on the tubular member is configured to radially enlarged and reduced in diameter by stretching in the axial direction (22), the opposite ends of tubular members (22) and (24) movable cylindrical body arranged to surround the tubular member (22) between the second protrusion (26), the first protrusion (24) and the second protruding portion (26) and (28), the catheter ( connecting the tip portion capable of abutting against at least (30), tip (30) movable cylindrical body (28) to the proximal end (42) tubular medical device 14) is inserted tip ( I provide support for supporting the 30) and (32).カテーテルセット(12)は、カテーテル(14)と、固定デバイス(10)とを備える。固定デバイス(10)は、軸線方向の伸縮によって縮径及び拡径するように構成された管状部材(22)と、管状部材(22)の両端部に設けられた第1突起部(24)及び第2突起部(26)と、第1突起部(24)と第2突起部(26)との間で管状部材(22)を囲んで配置された可動筒状体(28)と、カテーテル(14)が挿通される医療用管状デバイス(42)の基端部に少なくとも当接可能な先端部(30)と、先端部(30)と可動筒状体(28)とを連結し先端部(30)を支持する支持部(32)とを備える。
