Basic principles of the procedure Frijo Jose A

1. Percutaneous Coronary Interventions Basic principles of the procedure Frijo Jose A

4. Comparison- Diagnostic v/s Guiding catheters • Stiffer shaft • Larger internal diameter (ID) • Shorter & more angulated tip (110º vs. 90º) • Re-enforced construction (3vs.2 layers)

5. Guide catheter construction

6. Curves in guide catheter

7. Guiding catheter • For each given size of, its ID is either a standard, large or giant lumen • Larger sizes – • better opacification of the contrast • better guide support • allow pressure monitoring • increased risk of ostial trauma, vascular complications and the possibility of kinking of catheter shaft

10. Judkins and Amplatz Judkins • Extremely useful as a diagnostic cath - 1⁰ curve is fixed • Intubates small segment of ostium - ↓risk of trauma • Limitation while performing PCI - 1⁰ curve is fixed • May not be co-axial as cath makes an angle of ~90º with cor - may be difficult to pass balloons-esp LCX • JL- point of contact on ascAo -very high & narrow- ↑ chance of prolapse & dislodgement • JR- no point of contact on ascAo - extremely poor support

11. Backup force • 3 factors • Catheter size • Area of contact made by cath on Ao • Angle (theta) of cath on the reverse side of Ao • The angle (theta) determines the force that can dislodge the guiding catheter.

13. If this angle is ≈90⁰, it results in a greater backup force. Therefore a lower position is preferable as the point of contact on the reverse side of the aorta because the angle approaches 90º

15. Other Guiding Catheters Long tip cath like Xtra backup (XB) & Extra back up (EBU) • modifications for JL- stiffer & free 1⁰ curve • more co-axial & ↑support • XB distal tip - lies more horizontal within cor, sometimes pointing ↑, & intubating more LMCA • Longer segment of XB cath comes in contact with contra-lat wall of Ao- ↑ back-up support • XB cath- ~67% additional support v/s JR- at the cost of ↑ likelihood of trauma LMCA, esp - pre-existing plaque • ↑stiffer - ↑chance of injury XBLAD - ↑support for LAD interventions specifically

16. Xtra backup (XB) tip

17. Guide Catheter for RCA Interventions • JR or Hockey Stick (HS) is usually preferred • Extra-support-(CTO/tortuous)- AL1 • MP cath- espabn take-off, espinf • Three dimensional right curve (3 DRC) cath- tortuous, bent anatomy & postr/supr take off of RCA • XBR & XBRCA -new caths specifically for inf & sup take off of RCA respectively

19. Guide Catheter for LCX Interventions • JL 4 may be gently rotated clockwise to achieve a stable co-axial alignment • Ao root dialated / if JL 4 points anteriorly- JL 5 • If additional support –AL cath recommended • Unlike JL, a simple withdrawal can cause the tip to advance even furthe- best way to disengage an AL is to advance it slightly→prolapse tip out of cor & then rotate it out of the ostium • Vodacath- esp when a double PTCA of LAD & LCX in same sitting

20. The Voda catheter

21. Side Holes v/s No Side Holes • Side holes • where P gets freq damped (RCA) • where prolonged intubation of cor mandated (CTO) • to know P through out PCI (sole surviving art / LMCA) • P will not be damped • allow additnl blood flow out the tip- perfuse cor • may also avoid catastrophic dissections in the ostium of the artery if the guide catheter is not co-axial • it can be a false sense of security → Ao P, not cor P is being monitored • suboptimal opacification • ↓back up support- weak cath shaft & kinking at side holes

22. Guide Techniques for PCI of Tortuous Arteries Deep Seating of Guide • cath deeply intubated into cor- ↑support • RCA/LCX - clockwise rotation & gentle advancing of guide over the guide wire • LAD - counterclockwise rotation • ↑ risk of dissection & embolization, esp degenerated SVG

23. Guide Techniques for PCI of Tortuous Arteries Child in Mother Technique • 110cm long 5Fr guide (Child) in 100cm long 6Fr/7Fr guide catheter (Mother) • May provide up-to 70% more support • Trauma to vessel →dissection • Air embolism usually occurring during intubation of child catheter/during CAG performed via mother guide

24. Shepard's Crook RCA • Dramatic upturn with a ≈180º switchback turn • AL1/0.75 & 3DRC are best suited for this anatomy

25. Guide wire - construction • Most - calibre of 0.014 inch • Multi-layer constructions: • Core element (usually stainless steel/or nitinol): tapers at variable points towards wire tip to impart differential stiffness along wire's length • Terminal coil segment (often 30mm length; usually radio-opaque material e.g. platinum/iridium alloys): gives flexibility and allows wire tip to be shaped per operator requirements • Coating: most wires – silicone/Teflon outer coating to aid easy advancement. Some coated with a hydrophilic polymer coating that becomes a gel when wet to reduce surface friction and increase wire ‘slipperiness’

26. 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

27. 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

29. 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

30. 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

32. Wire Coating-hydrophilic/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

33. 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

34. Properties Of An Ideal Guidewire • Push transmission/steerability • Torque transmission/torquability • Body support/ trackability • Tip support/mobility • Flexibility • Tip durability/elasticity • Tip visibility and markers • Tactile feedback • Prolapse tendency

35. 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

37. 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 • General rule- when negotiating a vessel with J loop, distal bend ~ D of vessel—more bend -↑wire tip prolapsing, less bend -↓ steerability

38. 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

39. Workhorse wire: default choice - balance btw stiffness/support & flexible tip – majority lesions • Stiff wires: offer extra support for tortuous/calcified cor • Floppy wires: when vessel trauma is a concern (e.g. re-crossing a dissected lesion)

40. 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

41. 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

42. 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-

43. 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

44. Runthrough NS® wire

45. 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 / RunthroughHypercoat

46. CTO • Start with the intermediate wire • This provides 3g of distal force and moderate support • Conventional stainless steel core wire with 30mm of tip radio-opacity and 0.014 in. diameter • If this wire fails to cross, → Miracle series

47. Intermediate Wire (Asahi Intecc) • ●Tip load ............................... 3.0 g • ●Tip radiopacity .................... 3 cm • ●PTFE coating over the shaft

48. Miracle series (Asahi Intecc) • 0.014 in wires - specifically designed for CTO • 110mm of distal tip radio-opacity for optimal visualization • Come in 4 versions of ↑ distal force: 3g, 4.5g, 6g, 12g

49. ●Tip load ............................... 3.0 g ●Tip radiopacity .................. 11 cm ●PTFE coating over the shaft

50. ●Tip load ............................... 4.5 g ●Tip radiopacity .................. 11 cm ●PTFE coating over the shaft