The present invention provides a guide wire-catheter assembly, comprising: a catheter tube having a longitudinal channel, and a guide wire configured to be movable in the longitudinal channel characterized in that, the catheter tube comprises a bendable part near its distal end, wherein the bendable part comprises, in the circumferential direction of the catheter tube, a varying flexibility, such that exerting a longitudinal compression force in a proximal direction at a compression location distally of the distal end part results in bending of the bendable part, and in that the guide wire comprises an expandable part, wherein the expandable part is movable between a non-expanded position, in which a cross section of the expandable part is smaller than a smallest cross section of the longitudinal channel of the catheter tube and an expanded position, in which a cross section of the expandable part is larger than the smallest cross section of the longitudinal channel of the catheter tube, wherein, when the expandable part is in the non-expanded position, the guide wire can be moved completely in and out of the longitudinal channel of the catheter tube, and wherein, when the expandable part is in the non-expanded position, the expandable part is configured to exert the longitudinal compression force on the compression location in order to bend the bendable part of the catheter tube.
