What is the recommended approach for wire escalation in chronic total occlusions (CTO)?

Wire Escalation Strategy for Chronic Total Occlusions (CTO)

The recommended approach for wire escalation in chronic total occlusions (CTOs) is to begin with a polymer-jacketed, low penetration force, tapered guidewire for tapered proximal caps, and an intermediate penetration force polymer-jacketed or composite core guidewire for blunt proximal caps, with subsequent escalation to higher penetration force wires as needed. 1

Initial Wire Selection Based on CTO Characteristics

For Tapered Proximal Cap or Visible Channel:

• Start with polymer-jacketed, low penetration force, tapered guidewires
• Examples: Fielder XT (used in 45% of antegrade wire escalation procedures) 2

For Blunt Proximal Cap:

• Start with intermediate penetration force polymer-jacketed guidewires or composite core guidewires
• Examples: Pilot 200 (used in 56% of antegrade wire escalation procedures and successful in 36% of crossings) 2

Wire Escalation Algorithm

1. Initial Assessment:

   • Evaluate proximal cap morphology (tapered vs. blunt)
   • Assess occlusion length (short <20mm vs. long ≥20mm)
   • Identify distal vessel characteristics and bifurcations
   • Evaluate presence of collaterals for potential retrograde approach

2. For Short Occlusions (<20mm):

   • Favor antegrade wire escalation approach 3
   • Begin with soft tapered-tip polymer-jacketed guidewire
   • Rapidly escalate to stiffer wires if unsuccessful

3. For Resistant Areas:

   • Use stiff, high penetration force guidewires for highly resistant proximal caps
   • Examples: Confianza Pro 12 (used in 28% of procedures, successful in 11% of crossings) 2
   • After crossing 1-2mm of proximal cap, de-escalate to less penetrating guidewires to navigate through the CTO body 1

4. Microcatheter Support:

   • Always use a microcatheter for guidewire support (used in 81% of antegrade wire escalation attempts) 2
   • Corsair microcatheter is most commonly used (44% of cases) 2
   • Microcatheters provide better fluoroscopic feedback and greater freedom of advancement compared to over-the-wire balloons 1

Strategy Modification

• If antegrade wire escalation fails after reasonable attempts (typically 15-20 minutes), consider changing strategy 1
• Options include:
  1. Antegrade dissection/reentry (preferred for long occlusions ≥20mm)
  2. Retrograde approach (preferred for ambiguous proximal cap, poor distal target)

Success Rates by Complexity

• J-CTO score predicts success rates:
  • Easy (J-CTO 0): 83% success with antegrade wire escalation
  • Intermediate (J-CTO 1): 86% success
  • Difficult (J-CTO 2): 71% success
  • Very difficult (J-CTO ≥3): 43% success 4

Important Considerations

• Obtain coaxial guide position and strong guide support to facilitate CTO crossing 1
• Dual coronary angiography is essential for thorough assessment 1
• Complex CTOs (J-CTO score ≥2) often require dissection/reentry or retrograde techniques and should be performed by experienced operators 1
• Avoid getting stuck in a failure mode - be willing to change strategies if no progress is being made 1

Pitfalls to Avoid

1. Excessive wire manipulation without progress, which increases risk of perforation
2. Inadequate microcatheter support, making wire control difficult
3. Failing to de-escalate wire stiffness after crossing the proximal cap
4. Persisting with a failed strategy instead of changing approach
5. Inadequate guide support, making wire advancement difficult

By following this systematic approach to wire escalation in CTOs, operators can achieve high success rates while minimizing complications and procedure time.