The document discusses coronary guidewires, which are used to access and cross coronary lesions during angioplasty procedures. It provides a brief history of angioplasty and guidewire development. The key components and characteristics of guidewires are described in detail, including core material, tapering, tip design, coil placement, covers, coatings, and how these influence flexibility, torque, and other performance factors. Common guidewire classifications and specific guidewire models are also mentioned along with guidance on optimal guidewire positioning and potential complications.

1. CORONARY GUIDEWIRES
Dr. Raji Rajan
&
Dr. A. George Koshy
Government Medical College,
Trivandrum

2. •GRUNTZIG First performed Angioplasty in 1974
•1977 – First coronary angioplasty
•Polyvinyl Chloride balloon catheter with short guidewire
attached to its tip

3. •1982 – Simpson reported
First experience with over
the balloon system
•It had an independently
movable guidewire within
the balloon dilation
catheter

4. • To track through the vessel
• To access the lesion
• To cross the lesion atraumatically
• To provide support for interventional devices

5. Guidewire main characteristics
 Torque control Is an ability to apply rotational force at a
proximalend of a guidewire and have that force transmitted
efficiently to achieve proper control at the distal end
 Trackability Is an ability of a wire to follow the wire tip
around curves and bends without bucking or kinking, to
navigate anatomy of vasculature
 Steerability Is an ability of a guidewire tip to be delivered to
the desired position in a vessel
 Flexibility Is an ability to bend with direct pressure

6.  Prolapse tendency Tendency of the body of a wire
not to follow the tip around bends
 Radiopacity/visibility Is an ability to visualise a
guidewire or guidewire tip under fluoroscopy.
 Tactile feedback Is tactile sensation on a proximal
end of a guide wire that physician has that tells him
what the distal end of the guidewire is doing
 Crossing Is an ability of a guidewire to cross lesion
with little or no resistance
 Support Is an ability of a guidewire to support a
passage of another device or system over it

7. STRUCTURE
 CORE-Material
Diameter
Core taper
 TIP
 COILS, COVERS & COATINGS

8. Core
• Inner part of the guidewire
• Extents through the shaft of the wire from the
proximal to the distal part
• Distal taper
• Stiffest part of the wire that gives stability and
steerability

9. Core Material
Core material affects the flexibility, support, steering
and trackability
• Stainless steel
– superior torque characteristics, can deliver more push,
provides good shapeability and excellent support
– more susceptible to kinking and is less flexible
• 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

10. Core Diameter
• Influences the performance of the wire
• Larger diameter improves support and allows 1:1
torque response
• Smaller diameter enhances the flexibility
Core taper
• Variable length
• Continuous/segmented
• Short taper and smaller number of widely spaces
gradual tapers increases support and transmission
of push force
• Longer tapers and larger numbers of segmented
tapering increases flexibility

11. Tip
• 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

13. Coils, Covers & Coating
Keeps the diameter at .014 inch
• Coils
– Stainless steel
– Outer coil Design – Coils placed over tapered core and
tip of the wire
– Tip coil Design – Tip alone is covered with coils
– Flexibility, support, steering, tracking, visibility &
tactile feedback
– Radio opaque platinum coils
– Intermediate coils placed on the working length of the
wire

14. Coils

15. • Covers
– Polymer or plastic
– Lubricity
• Coating
– Distal half
– Affects lubricity and tracking
– Creates tactile feel
– Reduces friction
– Facilitates movement of wire within the vessel and
deliverability of intervention equipment

16. Hydrophobic
• Applied over the entire working length except
the distal tip
• Require no activation by liquid
• ↓friction, ↑trackability
• Preserves tactile feel, allows easier
anchorability / parking - esp CTO
• Silicone, Teflon

17. Hydrophilic
• Applied over the entire working length of wire
including tip coils
• Attracts water - needs lubrication
• Thin, non slippery, solid when dry→ becomes a gel
when wet
– ↓friction
– ↑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

18. Shapeability and shaping memory
• Shapeability - allows to modify its distal tip
conformation
• Shaping memory - ability of tip to return back
to its basal conformation after having been
exposed to deformation & stress
– Both do not necessarily go in parallel
– SS core wires -easier to shape (↑memory- nitinol
core)
– 2-piece core + shaping ribbon - easier to shape &
↑memory

19. Classification
Based on Tip Flexibility
• Floppy – Eg:- Hi torque balance middle weight, Hi
torque balance, Hi torque transvers
• Intermediate – Eg:- Hi torque intermediate,
Choice intermediate
• Standard – Shinobi, Boston Scientific
Based on Device support
• Light – Eg:- Hi torque balance
• Moderate – Eg:- Hi torque balance middle Weight
• Extra support – Eg:- Hi torque whisper

20. Based on coating
• Hydrophilic : Eg:- CholCETM PT Floppy
• Hydrophobic : Eg:- Asahi soft
Depending on tip load
• Floppy, Balanced & Extra support
• Tip load - force needed to bend a wire when
exerted on a straight guide wire tip, at 1 cm
from the tip
– Floppy - <0.5g
– Balanced – 0.5-0.9g
– Extra support - >0.9g

22. Guidewire Manipulations
• Two step process
• Shaping the wire tip
– It minimizes the amount of force applied to the
wire
– For steering into the vessel
– For visualization of torquing effort

23. Shaping the Wire Tip

24. Steering of the wire
• Small alternating rotations to left and right
• Excessive rotations should be avoided to
prevent wire tip fracture

25. Optimum guide wire positioning
• Should be placed as distally as possible in the
target vessel
• Allows extra support when crossing with
balloon/stent catheters
• ↓ chance of the wire becoming displaced
backwards across the lesion and necessitating
re-crossing
Avoid vessel perforation when positioning
wires with hydrophilic coatings very distally

26. Strategies if Guidewire fails to cross
• Make the guide more coaxial with the lumen
of the artery
• Use a balloon to direct the wire
• Modify the bend at the tip of the wire
• Change the wire

27. Complications
• Vessel perforations
– Uncommon <1%
– Risk factors
• Hydrophilic wires, core to tip
• Chronic total occlusions
– Diagnosis
• Angiographic diagnosis
• Small extraluminal extravasation of blush in the distribution
of target vessel
• Emergency echo to r/o pericardial effusion and tamponade
– Prognosis
• Extend of extravasation into pericardium

28. – Classification
• Type I – Extraluminal crater without extravasation
• Type II – Containing pericardial or myocardial
blushing
• Type III - having≥ 1 mm diameter with contrast
streaming: and cavity spilling
– Management
• Reversal of anticoagulations
• Prolonged balloon inflation
• PTFE covered stent
• Coil embolization
• Use of gel foams

29. Pseudolesions/Concertina effect
• Stenosis that appears in any artery after the coronary
guidewire is placed in the artery
• Appears in tortuous vessels that have been straightened
out by the guidewire

30. Diagnosis
• Will disappear if the wire is withdrawn
• Replacement of a stiff wire with a flexible floppy
wire eliminates pseudolesion
• Microcatheter or a balloon catheter can be
placed distal to the lesion
Complications
• In some cases cause hemodynamic compromise
and ischemia

32. Guidewire Entrapment
Factors
• Presence of calcified vessels (Eg:- RCA)
• Repeated use of wire for multiple interventions
• Repeated attempts at crossing the same lesion
multiple times with the same wire
• Two wires my become entrapped when the
“Buddy wire” technique is used
• Crossing fresh stent struts

33. Management
• Advance a small profile balloon or a small caliber
catheter (transit catheter) to the attachment site
and pull back gently
• When a second or “buddy wire” gets trapped
between a stent and the vessel wall gentle
traction can be used
• Surgery

34. Guidewire fracture and Embolization
• Risk factors are calcified lesion, bifurcation
stenting and prolonged procedures
• Management
– Surgery
– Snaring the Embolized wire fragment
• The Amplatz Gooseneck Microsnare
• The EnSnare Triple Loop Device
• The X Pro Micro Elite Snare
• The Alligator Retrieval Device
– Push and paste

35. 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

36. Fielder™ / Fielder FC™ (Asahi Intec Co.)
• Special guidewire - distal coil coated with
polymer sleeve & further coated with a
hydrophilic coating
• Provides advanced slip performance &
trackability for highly stenosed lesion & tortuous
vessels
• Very good torque performance
• Combines both slide and torque performance
• Primary wire used in the retrograde technique of
recanalization of CTO

38. Whisper
• Durasteel™ Core-to-tip designed to improve
steering, durable shape retention and tactile
feedback
• Full Polymer cover with Hydrophilic coating
intended for deliverability and smooth lesion
access
• Responsease™ “transitionless” core grind
designed to provide improved tracking and better
torque response
• Tip coils designed to provide softer, shapeable tip
and also improve tactile feedback

40. Galeo guide wire

41. Guidewire Strategies for Approaching CTO
• A) Guidewires for
Approaching Micro-channels
– Crosswire NT
– Whisper / Pilot
– Rinato
– Shinobe / Shinobe Plus
– ChoICE PT / ChoICE PT ES
– PT Graphix
– PT2
• B) Guidewires for Drilling
Strategy
– Persuader
– Miracle Bros
– Cross-It
• C) Guidewires for Penetrating
Strategy
– Cross IT
– Conquest Pro
– Liber 8
• D) Guidewires for Retrograde
Technique
– Fielder/FielderFC
– X -treme
– Whisper
– ChoICE PT2
– Runthrough / Runthrough
Hypercoat

42. Selection of a Guidewire
• Vessel anatomy
• Lesion morphology
• Devices to be used

43. Conclusion
It is suggested that the operator may use a
limited number of wires from the several
types available for purchase