PROBLEM TO BE SOLVED: To provide a stent, the radial stiffness of which varies gradually along part of the length thereof, and in which the radial stiffness of the end region thereof is less than the radial stiffness of a first region located further inside from the end thereof, and the variation in radial stiffness reduces the area of blood vessel wall which has low wall shear stress, reduces the possibility of recirculation, and reduces the risk of neointimal hyperplasia.SOLUTION: The stent comprises a central section 2, a first intermediate section 3, a first end section 4, a second intermediate section 5, and a second end section 6. The stent is movable between a collapsed delivery configuration and an expanded deployment configuration. In the delivery configuration the central section, the first intermediate section, the first end section, the second intermediate section, and the second end section are all cylindrically shaped. In the deployment configuration the central section is helically shaped, while the first end section and the second end section remain cylindrically shaped. Each intermediate section 3, 5 acts as a blended region to provide a smooth transition from the helical shape of the central section to the cylindrical shape of the non-stented blood vessel.SELECTED DRAWING: Figure 1【課題】径方向剛性は長さの部分に沿って漸進的に変動し、端部領域の径方向剛性は、端部から更に内側に位置する第１の領域の径方向剛性よりも小さく、径方向剛性における変動が、低い壁剪断応力を有する血管壁の領域を減少させ、再循環の可能性を低減させ、新生内膜過形成の虞を低減させるステントを提供する。【解決手段】中央区画２、第１の中間区画３、第１の端部区画４、第２の中間区画５、第２の端部区画６からなり、潰れた搬送形態と拡張した展開形態との間で可動であり、搬送形態において、中央区画、第１の中間区画、第１の端部区画、第２の中間区画、及び第２端部区画は全て円筒形状であり、展開形態においては、中央区画は螺旋形状であり、一方、第１の端部区画及び第２の端部区画は円筒形状にとどまる。各々の中間区画３，５は混合領域として働く構成とし、さらに中央区画の螺旋形状から非ステント血管の円筒形状への円滑な移行を与える構成とする。【選択図】図１
