Guidewire general techniques

Overview
The ability to cross an atherosclerotic lesion with a coronary guidewire depends upon both the performance characteristics of the giudewire and the skill of the operating physician. This chapter discusses the technique of crossing an atherosclerotic lesion with a coronary guidewire.

Workhorse Guidewire
It is a good general practice to use the same coronary guidewire for the majority of cases. In doing so, the operator becomes very familiar with the behavior characteristics of the wire, and becomes very sensitive to any changes in the behavior of the wire. In general, a flexible wire with a floppy tip that does not have a hydrophilic coating is a good choice as a workhorse guidewire. 90% of lesions should be able to be crossed with this workhorse guidewire.

Preparing the Guidewire

 * For the majority of lesions, create a curve at the tip of the guidewire which is roughly the length of the diameter of the vessel proximal to the lesion.
 * If you are attempting to cross a total occlusion the tip of the guidewire should be left straighter or with a minimal bend.

Strategies If the Guidewire Fails to Cross the Lesion

 * Adjust the guide so that it is more coaxial with the lumen of the artery
 * Use a balloon, transit, ultrafuse or twin pass catheter to direct the wire in a more favorable direction
 * Modify the bend at the tip of the wire. In tortuous segments, a more proximal secondary bend approximating shape the artery may be required
 * Change the wire

Safety Tips In Advancing The Coronary Guidewire

 * Avoid bending or buckling the wire. Buckling or bending of the wire can be a sign of a subintimal position.
 * Never push a wire if you feel undue resistance.
 * A ventricular premature beat could be a suggestion that the wire is too dital or has perforated the artery. Check the position of the wire in the presence of PVCs.
 * If the patient goes into sustained ventricular tachycardia, check the position of the wire but do not lose wire position if at all possible.
 * Be vigilant for coronary perforation when hydrophilic wires are used.
 * Once you cross with the hydrophilic wire consider switching out for a non-hydrophilic wire.
 * If there is a suspicion of a perforation, then an emergent Echo should be performed immediately while the patient is on the table.