6fr guideliner
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Intravascular ultrasonography and/or optical coherence tomography can assist with CTO crossing and stenting optimization, whereas covered stents and coils with appropriate delivery microcatheters are necessary for treating perforations, which is the most common complication of CTO PCI. Small balloons, various microcatheters, laser, atherectomy, and scoring balloons are often needed for balloon-uncrossable and balloon-undilatable lesions. Guide catheter extensions can increase support and also facilitate retrograde CTO PCI.
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Specialized equipment can facilitate dissection/reentry, and snares may be needed for retrograde guidewire externalization. CTO crossing should always be performed by advancing a guidewire through a microcatheter (preferred) or over-the-wire balloon, with careful selection of guidewires based on the lesion characteristics. CTO PCI equipment can be grouped into 12 categories: (1) sheaths, (2) guide catheters and guide catheter extensions, (3) microcatheters and support catheters, (4) guidewires, (5) dissection/reentry equipment, (6) snares, (7) equipment for balloon-uncrossable and balloon-undilatable lesions, (8) intravascular imaging, (9) equipment for managing complications, (10) equipment for minimizing operator radiation exposure, (11) balloons/stents, and (12) hemodynamic support devices. Availability of dedicated equipment and familiarity with its use are critical for successfully and safely performing chronic total occlusion (CTO) percutaneous coronary interventions (PCIs).