Endarterectomy versus Stenting in Patients with Symptomatic Severe Carotid Stenosis

1. Endarterectomy versus Stenting in Patients with Symptomatic Severe Carotid Stenosis Dr. Quan, Dr. Mirhashemi, Dr. Chiang N Engl J Med 2006; 355:1660-71

2. Objective • Know when to send patients for carotid artery stenting vs endarterectomy • Learn about Relative Risk • Know when is Relative Risk significant

3. Overview • Step 1 – Get patients with symptomatic carotid stenosis • Step 2 – Send patients to have carotid stenting or endarterectomy • Step 3 – Evaluate 30-day stroke or death of both groups

4. Purpose • To evaluate the efficacy of carotid stentingvsendarterectomy in patients with symptomatic carotid-artery stenosis

5. Time and Place • November 2000 to September 2005 • 20 academic and 10 non-academic centers in France • Approved by ethics committee

6. Centers and Investigators • 1+ Neurologist • 1+ Vascular Surgeon • Performed 25 endarterectomies • 1+ Interventional Physician • Performed 12 carotid-stenting or • Performed 35 stenting procedures in supraaortic trucks (5 in carotid artery)

7. Patients • 18+ years old • Hemispheric or retinal TIA or nondisabling stroke within 120 days • Carotid Artery Stenosis of 60 to 99% • Confirmed by angiography or both duplex scanning and MRA

8. Reference: http://neuro.wehealny.org/endo/proc_stents-angioplasty.asp

9. Reference: http://www.diagnosticclinic.com/health/articles/images/MRA/carotid_stenosis.jpg

10. Excluded Patients • Modified Rankin score of 3+ • Nonatherosclerotic carotid disease • Severe tandem lesions (proximal common carotid artery or intracranial artery that was more severe than carotid lesion) • Previous revascularization • History of bleeding disorder

11. Excluded Patients • Uncontrolled HTN or DM • Unstable Angina • Contraindication to heparin, ticlopidine, or clopidogrel • Life expectancy of less than 2 years • Percutaneous or surgical intervention within 30 days

13. Standard Procedures • Surgeons performed endarterectomy according to customary practice • Carotid stenting via femoral route with the use of cerebral protection device (01/2003 approved by safety committee)

14. Cerebral Protection Device Reference: http://radinfo.musc.edu/Interventional/index.php?module=pagemaster&PAGE_user_op=view_page&PAGE_id=58

15. Endarterectomy Reference: http://radinfo.musc.edu/Interventional/index.php?module=pagemaster&PAGE_user_op=view_page&PAGE_id=58

19. Anticoagulation • Aspirin 100-300mg qd • Clopidogrel 75 mg qd or • Ticlopidine 500mg qd • Take 3 days before and 30 days after stenting

20. Follow-up • 48 hours • 30 days • 6 months after treatment • Then every 6 months thereafter

21. End Points • Any stroke or death occurring within 30 days after treatment

22. Results

23. Predicted Statistics • Require 872 patients whether stenting was not inferior to endarterectomy with regard to the 30-day incidence of stroke or death • Expected 30-day incidence of stroke or death (Endarterectomy 5.6%, Stent 4%)

26. Local Injuries • Cranial-nerve injury was significantly more common after endarterectomy than after stenting (7.7% vs 1.1%, P<0.001) • Median hospital stay (stent, 3 days, endarterectomy – 4 days, P=0.01)

27. Weakness • by Dr. Mirhashemi

28. Strengths • Baseline patients characteristics in stentingvsendarterectomy are statistical similar

31. Adjusted Relative Risk • Age – 2.4 • History of stroke – 2.6 • More patients in the stenting group had contralateral carotid occlusion; none of them had a stroke after stenting

32. Strength • Computer-generated sequence randomly assigned to undergo endarterectomy or stenting • Operator independent

33. Learning Curve • No significant differences in outcome related to the number of stenting procedures performed in individual centers or to the experience of the interventional physicians • Experience with any new device was required before its use in the trial

34. Effects of Cerebral Protection • 30-day incidence of stroke or death was lower among patients who underwent stenting with cerebral protection (7.9%) than stenting alone (25%) • However, the RR over endarterectomy did not differ significantly (2.0 before and 3.4 after)

35. Antiplatelet Therapy • 30-day incidence of stroke or death after stenting didn’t differ significantly between pts who received dual antiplatelet therapy (19 of 211, 9.0%) and those who received single antiplatelet therapy (4 of 36, 11.1%, P=0.75)

36. Strengths • The events committee assess the occurrence of stroke, death, and other outcomes, unaware of the treatment assignments

37. Discussion • Lower surgical risk in our study • Previous trials – 30-day incidence of stroke or death after endovascular repair of the carotid artery is 8.1% (51 of 632)

38. Stenting • 30-day incidence of stroke after stenting in our study 9.2% which was higher than SAPPHIRE trial 3.6% (most patients had asymptomatic stenosis)

40. Safety and Futility • September 2005, safety committee recommended stopping enrollment due to increased risk of stroke or death after stenting and requiring to enroll more than 4000 patients to test the noninferiority of stenting

41. Conclusion • Patients with symptomatic carotid stenosis of 60% or more, treatment with endarterectomy results in lower rates of stroke or death at 30days and 6 months than does stenting.

42. THANK YOU…