An active guide wire (1) that can be used in a narrow blood vessel in a
complicate vascular system such as intracerebral is disclosed as well as a method
of making the same. The active wire comprises a bias coil spring (3); an
outer tube (4) having the bias coil spring (3) sheathed therewith
and providing an external wall for the active wire guide (1); and a shape
memory alloy (SMA) actuator (5) in the form of a flat sheet anchored in
and securely connected to the outer tube (4), wherein the flat sheet SMA
actuator (5) is shape memorized so as to bend in a direction of the thickness
of the flat sheet and has a shape running zigzag longitudinally thereof. The actuator
(5) is energized with an electric current and thereby heated to have its
leading end bent.