PROBLEM TO BE SOLVED: To provide a distal movable sheath that enables highly accurate myocardial biopsy for a heart of a cardiomyopathy patient in a short time. A tube (2) having a deflecting part (2a) at its distal end and having a lumen for guiding a biopsy forceps catheter, and a deflecting part (2a) provided at the proximal end of the tube (2) according to its rotation. The tube 2 has an operation part 3 for deflecting, and the tube 2 has a body part 2d having a straight body shape connected to the operation part, and a bent part 2e having a bent shape connected to a distal end of the body part 2d. And a connecting portion 2f that connects the distal end of the bent portion 2e and the proximal end of the deflecting portion 2a, and from the boundary position between the main body portion 2d and the bent portion 2e on the central axis of the main body portion 2d. The direction of the linear distance to the boundary position between the connecting portion 2f and the deflecting portion 2a on the central axis of the connecting portion 2f forms an angle other than 0° with respect to the central axis of the main body portion 2d. [Selection diagram] Fig. 6【課題】心筋症患者の心臓に対して短時間で確度が高い心筋生検を可能にする先端可動シースを提供する。【解決手段】その遠位端に偏向部２ａを有するとともに、生検鉗子カテーテルを案内する内腔を有するチューブ２と、チューブ２の近位端に設けられ、その回転に応じて偏向部２ａを偏向させる操作部３と、を有し、チューブ２は、操作部に接続される直胴状の本体部２ｄと、本体部２ｄの遠位端に接続される屈曲した形状を有する屈曲部２ｅと、屈曲部２ｅの遠位端と偏向部２ａの近位端とを接続する接続部２ｆと、を更に有し、本体部２ｄの中心軸上の本体部２ｄと屈曲部２ｅとの境界位置から、接続部２ｆの中心軸上の接続部２ｆと偏向部２ａとの境界位置までの直線距離の方向が、本体部２ｄの中心軸に対して０°以外の角度をなす。【選択図】図６
