A guidewire (1) for re-canalizing a vascular occlusion comprises a core wire (5) which terminates at its distal end (4) in a terminal member (7) for opening the occlusion. A helical coil sleeve (10) extends around the core wire (5) from the terminal member (7) to a location (11) along the core wire (5). The terminal member (7) defines first and second planar surface portions (13,14) which converge towards a distal transversely extending leading edge portion (8). As the terminal member (7) is urged through the vascular occlusion, the first and second surface portions (13,14) act on the occlusion to form an opening therethrough. A distal portion (28) of the core wire (5) is of spade-like configuration for facilitating bending thereof for directing the terminal member (7) out of a central major plane (35) defined by the distal portion (28) for facilitating aligning of the terminal member (7) with a branched vessel of the vascular system.