Simple percutaneous coronary intervention strategy with a novel guide extension catheter through a 5-Fr guiding catheter for a tortuous coronary artery.

A 78-year-old female diagnosed with effort angina underwent coronary angiography. The findings revealed subtotal occlusion in the tortuous circumflex. The lesion was initially treated with a drug-coated balloon alone; however, restenosis occurred after 2 months. Thus, percutaneous coronary intervention was performed again using a drug-eluting stent (DES) through a 5-Fr guiding catheter to minimize invasiveness. However, it was not possible to pass the lesion with the DES; thus, a novel guide extension catheter with a rapid exchange system was passed under balloon anchoring against the tortuous artery. The use of this guide extension catheter resulted in the successful delivery and implantation of the DES. This approach, using a novel guide extension catheter with a rapid exchange system through a 5-Fr guiding catheter, may facilitate the implantation of devices. Learning objective: Smaller guiding catheter (GC) using a 5-Fr contributes less invasive percutaneous coronary intervention (PCI) procedure for patients. However, sometimes GC stability and device pushability become insufficient in using 5-Fr GC. Hence, we report a case of PCI procedure through a 5-Fr GC with novel guide extension catheter, and it may be an alternative option when GC stability and device pushability are insufficient. It is meaningful to share this method of PCI procedure for all physicians.