Guidewire Types and Applications

Study Notes

Guidewires come in a variety of shapes and sizes, with different purposes and capabilities.
Non-steerable guidewires provide a supportive rail that allows the catheter to be advanced into position, but are not designed to negotiate stenoses or select branch vessels.
Steerable guidewires have shaped tips, and are constructed with good torque control so that when the shaft is rotated the tip turns a corresponding amount. This allows responsive 'steering'.
Hydrophilic guidewires are mostly steerable wires, which have a slippery 'hydrophilic' coating. This allows the wire to cross even the tightest stenosis if used properly.
Stiff guidewires are heavy-duty wires with particularly supportive shafts. A stiff wire may be required to support catheters/devices as they pass through occlusions/scar/fibrotic tissue or around challenging anatomy.
In some wires, the transition point is visible on fluoroscopy as the flexible tip is usually more radio-opaque.
Hybrid guidewires are a more recent development combining a steerable floppy tip with a supportive shaft. They are often pretty close to the original separate wires, and save both money and wire exchanges.