1. Antioagulation Protocols Post LAA Closures
CRT 2015
Washington, DC, Feb 21-24, 2015
10min
Antioagulation Protocols Post LAA Closures
Sameer Gafoor,
Horst Sievert, Ilona Hofmann, Laura Vaskelyte, Stefan Bertog, Predrag Matić, Markus Reinartz
CardioVascular Center Frankfurt - CVC
Frankfurt, Germany .

2. Disclosures Institution name Company Relationship
CardioVascular Center Frankfurt
Abbott, Access Closure, AGA, Angiomed, Boston, CardioKinetix, CardioMEMS, Cierra, Coherex, Coaptus, Cordis, CSI, Edwards, EndoTex, ev3, Gore, Guidant, Lumen Biomedical, Kensey Nash, Mind Guard, NDC, Neovasc, NMT, OAS, Occlutech, Ovalis, Pathway, Percardia, Rox Medical, Sadra, Sorin, St. Jude, Terumo, Topspin, Velocimed, Venus, Xtent
Consulting fees,
Travel expenses,
Study honoraria
Cardiokinetics, Access Closure, Velocimed, Cierra, CoAptus, Lumen Biomedical, Square One
Stock options,
Stocks

3. Main questions What do we know? What protocols are there?
What do we do with thrombus and leak?
What device modifications can we make to prevent leaks?

4. Let’s start with what we know from PROTECTAF
Prospective randomized study
2:1 allocation ratio device to control
800 patients enrolled

5. PROTECT-AF algorithm

6. PROTECT-AF Anticoagulation “cessation”
87% of patients at 45 days, more at later time points
Reasons for continuing on warfarin
Flow in LAA (n=30)
Physician order (n=13
Other (n=9)

7. What if cannot tolerate anticoagulation?

8. Contraindications to oral anticoagulation
Hemorrhagic/bleeding (active PUD, overt bleeding)
Blood dyscrasia
Unsupervised patients with senility and/or high fall risk
Other documented reason (including hypersensitivity to warfarin)

9. ASAP trial regimen Aspirin and clopidogrel for 6 months
Average stroke risk CHADS2 2.8
7.4%/year
7.3%/year with aspirin
5.0%/year with aspirin and clopidogrel
Actual ischemic stroke rate 1.7%

10. What are the other options for ACP? Asia-Pacific registry
Lam Asia-Pacific: 20 patients
DAPT x 4 weeks, then aspirin
TEE at 1 month
No thrombus seen on these patients

11. Brazil-Bern paper Guerios Brazil: 86 patients
DAPT x 4 weeks, then aspirin for 3-4 months; lifelong aspirin if coronary artery disease
TEE at 1 month
If thrombus, continued coumadin x 3 months then repeat TEE

12. Iberian registry for ACP
Lopez-Mingues – Iberian registry 167 pts hadthe most rigorous regimen
Aspirin Clopidogrel 600 x 1 day
Aspirin Clopidogrel x 3-6 months
Aspirin alone for up to 12 months
TEE at 1, 3, 6, and 12 months
Thrombus occurred – subcutaneous lovenox for 2 weeks, aspirin and clopidogrel continued

13. Iberian registry (continued)
CHADS2 rate of 3; translates to 9.6% at one year, observed was 3.9%

14. Iberian registry (continued)
TEE check 1, 2, 6, and 12 months
Thrombus still seen on 8% of patients
Overall range is 5-17%
Higher when dual antiplatelet therapy withdrawn in first 2 months, falls with 2-3 week course of enoxaparin

15. Overall ACP registry

16. What about leaks?

17. Residual leaks after catheter closure PROTECT AF
“Any flow around the device”
Viles-Gonzalez JF J Am Coll Cardiol. 2012;59:

18. Residual leaks after catheter closure PROTECT AF
After 12m 32% had at least some degree of peri-device flow
Size of Leaks
Minor (<1mm) %
Moderate (1-3mm) 62.4%
Major (>3mm) 36.8%
Patients with residual leaks >5 mm were treated with anticoagulation
Viles-Gonzalez JF J Am Coll Cardiol. 2012;59:

19. .... because in PROTECT AF these patients received anticoagulation
We can only assume (from surgical experience) that a large leak (>5mm) is a risk factor for stroke ...
.... because in PROTECT AF these patients received anticoagulation

20. Is a small leak (<5mm) a risk factor for stroke?

21. PROTECT-AF Primary Efficacy Endpoints by Leak Severity
A higher chads 2 score equals a higher stroke risk
Comparison of primary efficacy (red), ischemic stroke (yellow), and a composite endpoint of stroke and systemic embolization (orange), showing no significant statistical relationship between the presence or severity of peri-device flow.
Primary Efficacy Event Rates in Patients With and Without Peri-Device Flow
Any Residual Flow
No Flow p
Efficacy
9/182 (5%)
18/263 (7%)
0.572
Ischemic stroke/systemic embolism
5/182 (3%)
11/263 (4%)
0.669
Viles-Gonzales, J et al. JACC 2012; 59(10):923-9.

22. What do we do with a large leak?
As you may have expected we started to close them

23. Residual leak after Watchman
+ AVP II
72 M with AF
TIA 2006, CAD, GI Bleeding
Watchman (31mm) Implantation May 2011
Leak at TEE 19 months later
M/72 AF, TIA 2006, CAD, GI Bleeding
Watchman (31mm) Implantation
Leak at TEE 19 months later

24. 8Fr Introductory sheath, Amplatz Extra Stiff
Amplatzer Vascular Plug (AVP II) 10 mm

25. Deployment of Device and Final Result

26. So there are many different protocols
How do we make sense of this?

27. We find our own middle ground: the CVC Protocol
Anticoagulation with warfarin may be too much – and many patients do not want this
Dual antiplatelet therapy for 3 months, then aspirin alone for 6 months
TEE at one month
Check for significant leak or thrombus

28. We find our own middle ground: the CVC Protocol
If thrombus
Warfarin or enoxaparin for 3 months then TEE again; remove aspirin and clopidogrel
If at repeat TEE still thrombus, continue for another three months with warfarin
If leak
If greater than 5 mm with high-risk criteria such as filling the LAA or reaching the back of the LAA – consider closure

29. Better than treating is to prevent the problem
How do we make the devices better?

30. How do we make devices better?
Risk of thrombus until neoendothelialization forms
Often checked in canine studies (many limitations)
At 28 days, all surfaces of Wtchman were covered
At 30 days, one canine had focal uncovered area at lower edge of disc and at the screw

31. Watchman vs. ACP Canine model 30 days
Kar S et al. JACC Interv 2014

32. However let’s not jump to conclusions yet
ACP
Amulet
New St. Jude system is called Amulet
Different end screw in place that is shorter

33. Amulet: Recessed End Screw
uniform surface in the left atrium
potentially less risk of thrombus formation
Preclinical canine model: Mature and stable neointima covering the device surface (arrows); the device was filled by organized thrombus (asterisk). 90 day cohort (H&E)

34. Thank you!