Slowly to-and-fro movement of the stiff wire with rotation changing up to 180°. Advancement of the wire depends about CTO body length. This manuever makes several tears of tissue layers and creates micro-connections from subintimal to the luminal space
After scratching technique, de-escalation is needed to intermediate polymer jacket wires like Pilot 200/Gladius/Raider to try intraluminal redirection. For polymer jacket wires to ease re-entry, make primary typical CTO curve and secondary 30-45° curve.
When subintimal, a stiff wire scratching technique can serve as a good option for luminal wire redirection. It is easy reproducible, fast, cheap, can be successful in many cases. Scratching manuever is followed by specific wire de-escalation into intermediate tip wight polymer jacket wires.
Can serve as alternative or previous try to classic ADR with Stingray, subintimal guidewire redirection (SGR) or anterograde dual access technique (ADA) with Recross, subintimal anchor technique with double lumen microcatheters, classic parallel wire technique, AFR…. All mentioned techniques consume much more time and cost to complete the procedure.
Caution is needed, perforation possible with stiff wires, try not to retract the wire proximally to the cap, scratch mostly in the CTO segment and short part of the target, avoid much manipulation at the distal target to prevent hematoma formation, try not to follow the wire with the microcatheter to prevent anterograde hematoma filling, do not inject from the anterograde guiding…
Use double-wrist access when possible to reduce complications
Use of ULDR – ultra low dose radiation protocol, 3.75-4 fps fluoro/low for dramatic reduction of radiation exposure towards the patient and cath lab. Staff.
Best regards,
Mihajlo Kovacic