PROBLEM TO BE SOLVED: To maintain an outer surface of a pericardium in a state of being exposed from a peripheral tissue without damaging the pericardium regardless of hard pulsation of a heart.SOLUTION: A device 1 for medical treatment includes: a slender cylindrical insertion unit 2 inserted into a body through a tissue and disposed with a tip face 2d adjacent to an outer surface of a pericardium A and position adjusting means 3 for moving the tip face 2d of the insertion unit 2 in a thickness direction of the pericardium A depending on displacement in the thickness direction of the pericardium A.COPYRIGHT: (C)2014,JPO&INPIT【課題】心臓の激しい拍動に関わらず、心膜に損傷を与えることなく、心膜の外面を周辺組織から露出させた状態に維持する。【解決手段】組織を貫通して体内に挿入され、先端面2dを心膜A外面に近接して配置される細長い筒状の挿入部2と、心膜Aの厚さ方向の変位に合わせて挿入部2の先端面2dを心膜Aの厚さ方向に移動させる位置調節手段3とを備える医療用デバイス1を提供する。【選択図】図2