Coronary & Peripheral Guidewires Roby Rakhit
1 st wire for PTCA introduced by Simpson & Roberts in 1982
Choice of Guidewire Anatomy Vessel angulation, tortuosity, bifurcation, CTO Lesion Characteristics Location: ostial, bifurcation, distal Morphology: length, diffuse, calcific Device Strategy Size and length of stent Adjunctive technology eg rotablation
Guide wire - construction Most - calibre of 0.014 inch 3 main components of guidewire design: central core outer covering flexible distal tip The wire tip may be further subdivided into spring coil & short distal tip weld Also, all guidewires have a specific surface coating applied
Central core Longest & stiffest portion of guidewire Tapers distally to a variable extent 2-piece core- distal part of core does not reach distal tip of wire shaping ribbon, extends to distal tip 1-piece core- tapered core reaches distal tip weld 2-piece easy shaping & durable shape memory 1-piece better force transmission to tip & greater tactile response for operator
Central core Stainless steel superior torque characteristics, can deliver more push, provides good shapeability of tip in core-to-tip design wires more susceptible to kinking Durasteel- better tip shape retention and durability Nitinol pliable but supportive, less torquability than SS generally considered kink resistant & have a tendency to return to their original shape, making them potentially less susceptible to deformation during prolonged use
Distal tip Flexible, radio-opaque part Consists of spring coil extending from distal untapered part of central core to distal tip weld Integrates tapered core barrel (as well as shaping ribbon in 2-piece wire) Spring coil-variable length (1-25cm)-radio-opaque section located at its terminal end Distal tip weld- short ( 2mm)compact cap forming the true distal end of the wire - to trauma while the wire is traversing vessels
Wire Coating-hydrophilic vs hydrophobic Hydrophobic Repels water - requires no actuation/wetting friction (to ½ V/S no coating), trackability Preserves tactile feel, allows easier anchorability / parking - esp CTO Silicone, Teflon
Hydrophilic Attracts water - needs lubrication Thin, slippery, non-solid when dry becomes a gel when wet friction(⅙ no coating) glide through tortuous trackability Thrombogenic tactile feel- risk of perforation Tendency to stick to angioplasty cath Useful in negotiating tortuous lesions and in finding microchannels in total occlusions Lubricity is highest with hydrophilic wires, less with Silicone coating and least with PTFE or Teflon coating
Properties Of An Ideal Guidewire Steerability Torquability Trackability Tip support/mobility Flexibility Tip durability/elasticity Tip visibility (radiolucency) and markers Tactile feedback Prolapse tendency
Push transmission/steerability: ability of a guide wire tip to be delivered to the desired position in a vessel Torque transmission: ability to transmit rotational forces from the operators hand to the tip Body support/ trackability: ability to advance balloon catheters/other devices on guidewire Tip support/mobility: Allows moving the distal tip to search for the true lumen Tip durability/elasticity: Permits shape memory retention of the distal tip throughout Tactile feedback: feel of the wire tip s behavior, as perceived by the operator better appreciated with non-coated / hydrophobic coated, coil tipped wires and it with hydrophilic coating
Types Of Guidewires Depending on tip load- Balanced, Extra support, Floppy Tip load- force needed to bend a wire when exerted on a straight guide wire tip, at 1 cm from the tip Balanced 0.5-0.9g Extra support - >0.9g Floppy - <0.5g
Workhorse wire: default choice - balance btw stiffness/support & flexible tip majority lesions Stiff wires: offer extra support for tortuous/calcified coronaries Floppy wires: when vessel trauma is a concern (e.g. re-crossing a dissected lesion)
Workhorse (frontline) Guidewires ATW/ATW Marker Stabilizer BMW / BMW Universal Zinger Cougar XT Asahi Light / Medium Asahi Standard Asahi Prowater Flex Choice Floppy Luge IQ Forte Floppy Runthrough NS Galeo
Balance Middleweight Universal wire (Abbott Vascular/Guidant, Santa Clara, CA) Quite steerable - tip is suitable for bending in a J configuration for distal advancement into the distal vessel bed with minimal trauma while still maintaining some torque shape retention relatively poor -any J configuration tends to become magnified over time consequent loss in steerability moderately torquable- progression - minimal friction (light hydrophilic coating) - Dye injection may also be helpful to propagate distal advancement suitable for rapid, uncomplicated interventions low risk to cause dissections/distal perforations support - low to moderate
Balance Middleweight wires from the generation previous to the Universal lack light hydrophilic coating at the tip more steerability but requires greater effort for distal advancement more direct tactile feedback (v/s more automatic progression Universal) Support-moderate -power steering-
Guidewire Strategies for Approaching CTO A) Guidewires for Approaching Micro-channels Crosswire NT Whisper / Pilot 50 or 100 Shinobe / Shinobe Plus ChoICE PT / ChoICE PT ES PT Graphix int B) Guidewires for Drilling Strategy Miracle Bros Cross-It C) Guidewires for Penetrating Strategy Cross IT Conquest Pro D) Guidewires for Retrograde Technique Fielder/FielderFC X -treme Whisper ChoICE PT2 Runthrough / Runthrough Hypercoat
Retrograde CTO of RCA via LAD (Fielder wire)
Runthrough NS wire unique dual core design main shaft core of SS & a distal core of nitinol alloy, which extends into a nitinol shaping ribbon distal tip is hydrophilic coated
Runthrough NS wire
Guidewire Complications 1. Perforation Incidence <1%, caution hydrophilic wires 2. Guidewire Entrapment/fracture Calcified lesions Bifurcation lesions 3. Pseudolesions concertina effect May lead to unecessary stenting
ABBOTT WIRES Asahi Family of Wires Asahi by Abbott vascular ASAHI Confianza Coronary Guide Wires ASAHI Grand Slam Coronary Guide Wires ASAHI Light Coronary Guide Wires ASAHI Medium Coronary Guide Wires ASAHI Miracle Bros Coronary Guide Wires (3g, 4.5g, 6g and 12g) ASAHI Prowater Coronary Guide Wires ASAHI Prowater Flex Coronary Guide Wires ASAHI Standard Coronary Guide Wires Balance Wires by Abbott Vascular BALANCE (HI-TORQUE BALANCE Coronary Guide Wire) BALANCE (HI-TORQUE BALANCE MIDDLEWEIGHT UNIVERSAL Coronary Guide Wire) HI-TORQUE CROSS-IT XT Coronary Guide Wires by Abbott vascular 100 XT 200 XT 300 XT
BOSTON WIRES Crossing guide wires ChoICE PT ChoICE PT Extra support PT PT Graphix Intermediate Forte IQ Luge Mailman
CORDIS WIRES ATW All Track Wire ATW Marker Wire WIZDOM Steerable Guidewires WIZDOM ST Steerable Guidewires STABILIZER Balanced Performance Steerable Guidewires STABILIZER Plus Steerable Guidewires STABILIZER XS Steerable Guidewires STABILIZER Marker Wire SHINOBI Steerable Guidewires SHINOBI Plus Steerable Guidewires REFLEX Steerable Guidewires Steer it Deflecting Tip Guidewire E-1 Steerable Guidewire Accessories CINCH QR Extension Wire EASY TWIST Torquing Device
MEDTRONIC WIRES Cougar Zinger Persuader Thunder
Peripheral wires Spartacore (Abbott Victory 14 & 18 Mandril (steerable)