10:14 Calcium and CTO Claudia Cosgrove (London - UK) ___________________________________________ PARALLEL SESSION Challenges And Opportunities In Cto Recanalization Auditorium Zubin Mehta - Saturday 10:00 - 11:10 Chairperson: Jonathan Hill (London - UK) Discussants: Lesnek Bryniarski (Krakow - PL), Ugo Fabrizio (Vercelli), Paul Knaapen (Amsterdam - NL), Eugenio La Scala (Ollioiouls - F) ___________________________________________ 15th Experts Live CTO, EUROCTO Club meeting in partnership with the GISE CTO meeting. September 8th - 9th, 2023 Florence, Italy

1. Claudia Cosgrove
Calcium in CTO

2. Pathophysiology
Sakakura, EHJ, 2014
CTO with organising thrombus Proteoglycan-rich CTO Calcified CTO
CTO duration

3. The proximal cap is often calcified

4. Post-CABG CTO
Accelerated atherosclerosis in grafted arteries
Blood stasis, low shear stress
Post-bypass CTOs more severely calcified than non-bypass CTOs
Within CTO segment
In adjacent proximal and distal vessel
Distal cap is more likely to be calcified than in non-CABG CTOs
(exposed to aortic pressure)
Less likely to negatively remodel ?calcium acts as scaffold

5. Success and safety in calcific CTO

6. Imaging of coronary calcium in CTO

7. Procedural challenges- Lesion crossing

8. Techniques to resolve an uncrossable proximal cap
McEntegart and VP Ed

9. Techniques to resolve an undilatable proximal cap
McEntegart and VP Ed

10. Procedural challenges- calcium modification
Oknes, JIC, 2021

13. Shockwave IVL
Potential mechanistic advantages
13
No requirement for a
specialized wire.
Able to protect side branch
with second wire.
Lithotripsy allows Ca2+ modification to
be performed at low balloon pressure
thereby avoiding the risk associated with
high pressure inflations.
Shockwaves are selective for
disrupting Ca2+.
Shockwaves pass through the plaque
/ vessel wall enabling modification
of deeper lying Ca2+.
Disrupted Ca2+ remains within
vessel wall thereby reducing the
risk of distal embolization.
As with balloon-based therapies, the Shockwave
IVL system is easy to learn compared to other
forms of Ca2+ modification.

14. Rotational atherectomy in CTO: proximal cap modification

15. Rotational atherectomy in CTO: undilatable lesion after wire crossing

16. • Calcium is common in CTO, particularly in post-CABG
• Calcium is problematic during CTO crossing and optimizing stent
expansion
• Calcium is an independent predictor of procedural success,
complications and long term clinical outcomes
• Specific techniques and tools can facilitate crossing calcified proximal
and distal caps, the occlusive segment and in re-entry
• IVUS is recommended to confirm calcium modification and stent
optimisation