Guiding catheters for directional coronary atherectomy.

The size and rigid length of the directional coronary atherectomy catheter creates a new set of demands and constraints for guiding catheter manufacturers. Large lumen guides with gradual, rather than abrupt, curves are necessary, and a number of unique shapes have been developed to address native coronary and saphenous vein graft anatomy. The guiding catheter has a tendency to straighten and disengage from the coronary or graft ostium as the DCA device is advanced, and coaxial alignment of the body of the guiding catheter is essential to engage the atherectomy device. Power-positioning and deep seating of these large lumen, thin walled, and rather rigid guides should be avoided, to minimize ostial complications. These guiding catheters require modifications of usual techniques for introduction, manipulation and maintenance or coaxial alignment with the target vessel, as well as for withdrawal through the aortic bifurcation. Strategies for successful guiding catheter selection and utilization are outlined.