PROBLEM TO BE SOLVED: To provide a suction catheter, a suction system, and a treatment method capable of effectively removing an object flowing in a living body lumen and providing a stable procedure.SOLUTION: A suction catheter 500 inserted into a blood vessel for sucking thrombus 301 in the blood vessel includes: a tubular base part 503； and a distal side tubular part 505 located on the distal side of the base part 503, which is inclined toward a predetermined direction X with respect to a central axis of the base part 503. The distal side tubular part 505 includes a distal side opening 506 at the end of the distal side that is inclined with respect to a central axis of the distal side tubular part 505. The distal side opening 506 is open facing a direction opposite to an inclined direction X with respect to the base part 503 of the distal side tubular part 505.SELECTED DRAWING: Figure 21COPYRIGHT: (C)2020,JPO&INPIT【課題】生体管腔内を流れる物体を効果的に除去でき、かつ安定した手技を提供できる吸引カテーテルおよび吸引システム並びに処置方法を提供する。【解決手段】血管内に挿入されて当該血管内の血栓３０１を吸引するための吸引カテーテル５００であって、管状の基部５０３と、前記基部５０３の遠位側に位置して前記基部５０３の中心軸に対して所定の方向Ｘへ向かって傾斜する管状の遠位側管状部５０５と、を有し、遠位側管状部５０５は、遠位側の端部に遠位側管状部５０５の中心軸に対して傾斜する遠位側開口部５０６を有し、遠位側開口部５０６は、遠位側管状部５０５の基部５０３に対する傾斜方向Ｘと反対方向を向いて開口している。【選択図】図２１
