Summary and Recommendations
Specific recommendations regarding CTO PCI technique are as follows:
- Dual injection is recommended for nearly all CTO PCI to determine the optimal crossing strategy and guide wire advancement into the distal true lumen.
- Strategies that provide enhanced guide catheter support (such as long sheaths, large-bore guiding catheters, use of guide catheter extensions, and anchor techniques) are important for maximising the success rate and efficiency of CTO PCI.
- Use of an over-the-wire system is strongly recommended in CTO PCI for enhancing the penetrating power of the guidewire, enabling change in tip shape and allowing guidewire change (stiff CTO guidewires are not optimal for crossing non-occluded coronary segments).
- Adherence to a procedural strategy (Figure 1) that standardises CTO technique and facilitates procedural success is recommended. Such a strategy would permit stepwise decision making for antegrade and retrograde methods, inform guidewire selection and incorporate alternative approaches for instances of initial failure.
- Given the paucity of long-term outcomes with use of novel crossing techniques (antegrade dissection/re-entry and retrograde), antegrade wire escalation is the preferred frontline CTO crossing technique, if technically feasible.
- Using measures to minimise radiation exposure (including but not limited to use of 7.5 frames per second fluoroscopy and use of low magnification) and contrast administration is recommended.
- CTO PCI is best performed at centres with dedicated CTO PCI experience and expertise. Use of crossing difficulty prediction tools, such as the J-CTO score,9 can facilitate the selection of cases with a high likelihood of quick crossing that can be attempted at less experienced centres.