14th Experts Live CTO September 2nd - 3rd, 2022 - Mainz, Germany Main Session - Session 5: Retrograde – Technical aspects What is an interventional collateral? Sudhir Rathore, Guildford, UK Room: Guteberg Hall (Auditorium) - Saturday 10:10 Chairmen: Alfredo Galassi, Palermo, Italy; Dimitrios Karmpaliotis, Morristown, USA; Nicolaus Reifart, Königstein, Germany

1. What is an Interventional Collateral??
Dr Sudhir Rathore
MD, FRCP, FACC, FESC
Consultant Interventional Cardiologist
Frimley Health NHS Foundation Trust

2. Purpose and Definition
• IC is required for the successful completion of the CTO recannalization
in 1/3 of the cases.
• Collateral which allow successful passage of the currently available
guide wires and the MC Devices into the CTO segment.
• Successful retrieval of the hardware.
• Haemodynamic compromise: Non dominant.
• Minimise CC injury, perforation and Cardiac Tamponade.
• Definition could vary with Operators preference and experience.

3. CC, Werner Classification

4. Patterns of Septal
Collaterals
1. < 90 degree
2. >90 degree
3. Corkscrew
4. Corkscrew
5. Recipient vessel>90
6. >90 R Vessel

5. Patterns of Epicardial
channel
•Usually very tortuous,
Large, CC2, visible.
•Easier to cross with
Caravel.

7. Logistic Regression- Predictors of Retrograde Failure
Variables Odds Ratio 95% C.I P value
Channel used (epicardial) .515 0.28-9.57 0.656
CC angle with donor vessel 0.867
CC-Recipient vessel angle not
visible
47.09 1.65-1340.42 0.024
Tortuousity of CC-corkscrew 8.31 1.63-42.36 0.011
CC TYPE 1 2.16 0.43-10.74 0.346
Bridging Collaterals 1.09 0.29-4.00 0.896
Significant Side Branch 1.51 0.33-6.72 0.588
Severe tortuousity .757 0.11-4.94 0.771
Severe Calcification 2.67 0.51-13.93 0.243
CTO Length>20mm 0.971 0.93-1.01 0.138
Ostial location 1.34 0.22-7.98 0.744

8. EPI CTO
Score
Z Huang et al, JOIC, Aug 2017

9. CC Huang, HL Kao.
Circulation, CI, 2018

10. Tortuosity

11. Comparison of Scores

12. W Wang, B Luan,
https://doi.org/10.2147/CIA.S263216

13. Results

14. Evidence Based CC Morphology: Interventional
Collateral
• (C) Direct connection between the Donor and recipient artery:
RAO Cranial and Caudal View.
• (T) Tortuosity: Less bending, corkscrew unfavourable.
• (D) Diameter: > 0.9 mm, CC2>CC1>CC0
• (S) No Side branch at the tortuosity.
• (E) CC exit- CTO distal cap> 5 mm.
• (A) CC Entry and Exit angle> 90 degrees.
• Less tortuosity of the Donor vessel at the site of IC origin: PDA

15. Collateral channel isolation
• Selective CC angiography to assess the course and morphology
• Wires: Sion, Fielder FC, Fielder XT ,SUOH 3, with Corsair/ Finecross support

16. Wiring the collateral channel

17. LAD CTO: Multiple RCA Septal Collaterals: Which to use?

18. Selective Injection: MC: Using 2ml Leur Lock syringe

19. Surfing: Unsuccessful

20. Further sub selective septal injections

21. Further different Collateral Injection

22. Successful Collateral crossing into the distal LAD

23. RCA CRO: LAD septal and selective injections and no direct
connection

24. Different Septal: Direct connection and Interventional collateral

25. Successful Wiring and collateral crossing

26. RCA CTO: Selective septal injection

27. Successful Wire and device crossing

28. Ostial LAD CTO: Ambiguous Proximal Cap

29. Retrograde Wiring: Sion

30. Finecross and distal cap

31. Final Angiogram

32. Ostial LAD CTO: RCA Septal collaterals , SUOH 03

33. Caravel: Exchange to CP 12, Cautious

34. Simultaneous bilateral angiogram
Bilateral simultaneous angiography should be performed at low magnification
And without panning

35. Retrograde wiring with Fielder FC and Corsair

36. RCA CTO: Mid to Distal , Epicardial CC

37. Retrograde: Epicardial CC, CARAVEL150, Sion Black, Suoh 3

38. CC Crossing with Suoh 3 wire

39. Final Result

40. Second Attempt: AL1.0 SH, Anchor wire

41. Ipsilateral Epicardial Collateral, Corsair 150, Sion wire

42. Corsair Advancement, RWE, Gaia Second, Confianza Pro

43. Final Successful Strategies
RECHARGE Expert JCTO EURO CTO PROGRESS OPEN CTO
AWE (62%) (91%) 88.1% (55%) 59%
Parallel wire
IVUS usage entry
NA 14.4 (82.5%)
3.2 (75%)
Retrograde
RWE
RDR(RCART)
CART
Kissing Wire
(62%)
28
67
3
(87%)
16.3
62.4
3
17.7
79.3%
31
20
15
16
(60%)
17.8
66.1
1.7
1.7
62%
30
70
Collateral used
Septal
Epicardial
Bypass
64
25
6
57.9
19.6
3
65
13
5
57.3
34.7
15.7
ADR
Sting ray
STAR
LAST
(66%)
78
9
13
NA (66%)

44. Reasons of procedural failure
● Inability to cross collateral channel with wire= 15/20%.
● Inability to cross with device after successful wire
crossing= 5/10%
● Procedural failure after successful crossing CC with wire
and micro-catheter= 5/10%.

45. Take Home Message
•Careful CC Assessment in Orthogonal views to
visualize the course.
•IC helps in planning the case and efficient use of
resources.
•Favourable CC morphological features allows safe
completion of the procedure.
•Advancement in guide wire and MC technology
allows successful traversing and retrieval of the
Hardware.

46. Take Home Message
•Careful CC Assessment in Orthogonal views to
visualize the course.
•IC helps in planning the case and efficient use of
resources.
•Favourable CC morphological features allows safe
completion of the procedure.
•Advancement in guide wire and MC technology
allows successful traversing and retrieval of the
Hardware.