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To stent or not to Stent

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					  To Stent or Not to Stent?
Treatment of Carotid Artery
Stenosis in the 21 st Century

        Robert R. Carter MD
          April 21st 2010
           Grand Rounds
   Department of Vascular Surgery
       University of Kentucky
                   Goals
• Review history of carotid artery disease
• Summarize evidence for surgical intervention
• Summarize trials that compare stenting and
  carotid endarterectomy (CEA)
• Review FDA approved indications for stenting
                            1875
• First report linking
  stroke with extra cranial
  vascular disease by Sir
  William Richard
  Gowers.
   – Described a patient with
     right hemiplegia and
     blindness in the left eye.
   – He attributed this
     syndrome to an
     occlusion of the left
     carotid artery in the
     patient’s neck.
                            1914
• James Ramsay Hunt
  emphasized extra cranial
  carotid artery occlusive
  disease as a cause of stroke.
• Urged examination of the
  cervical portion of the
  carotid artery during
  autopsy.
• Suggested that transient
  cerebral ischemia was
  equivalent to intermittent
  claudication of the brain
  and represented a
  prodrome to a major stroke.
                        1937
• Egas Moniz reported
  that arteriography could
  be used to diagnose
  carotid artery occlusion.
• What is a TIA?

• What is a Stroke?

• How are they related?
   Transient Ischemic Attack (TIA)
• Definition
  – Any transient neurologic deficit lasting from
    several seconds to many hours but not longer
    than 24 hours.
                         TIA
• Two mechanisms
  – a brief vascular spasm in a partially blocked artery
    impedes blood flow to the brain temporarily
  – Small “mini” strokes where pieces of plaque
    dislodge and embolize
• Not benign
  – Degree of cerebral atrophy and infarction linked to
    number of TIA’s
               Amaurosis Fugax
• Definition
  – temporary monocular blindness (shade coming
    down over the eye) caused by embolization to the
    ophthalmic artery (first branch off the internal
    carotid artery)
  – TIA
  – Ulcerated plaque at common carotid bifurcation
    usual source
              Amaurosis Fugax
– Fundoscopic exam
  shows plaque traversing
  the retina
– First described by Robert
  W. Hollenhorst in 1961
   • Hollenhorst bodies
                      Stroke
• Definition
  – A sudden loss of brain function caused by an
    interruption in the supply of blood to the brain. A
    ruptured blood vessel or cerebral thrombosis may
    cause the stroke, which can occur in varying
    degrees of severity from temporary paralysis and
    slurred speech to permanent brain damage and
    death.
  – Neurologic deficit lasts longer than 24 hours
  How are TIA and stroke related?
• 35% of patients with a TIA will have a stroke in
  their lifetime
  – 50% of these will occur in the year following first
    TIA
• After first year stroke risk is 5% per year
                    Stroke
• 3rd leading cause of death in the united states
• 2nd most common cause of cardiovascular
  death
• #1 cause of death from a neurologic disorder
http://www.cdc.gov/
                        Stroke
• Incidence of new stroke is 160/100,000
• Annual financial impact estimated to be $45.3
  billion/year
  – Death
  – Disability
     • Long term care
     • Medical expenses
     • Inability to return to previous employment
                         Stroke
• Prognosis
  – 80% survive initial event
     •   29% regain normal function
     •   36% return to work
     •   18% unable to work, but can take care of themselves
     •   4% require custodial care
• Natural history
  – only 50% of stroke victims will be alive at five
    years.
• Is TIA a risk factor for stroke?
   – 33% of TIA patients will suffer a stroke within 5
     years, 17% within 1 year
• What about asymptomatic carotid stenosis?
                       Outcome in patients with
                    asymptomatic neck bruits 1986
     • NEJM
             – prospectively followed 113 asymptomatic patients
               with carotid stenosis ≥ 75% (Doppler)
             – 1 year 18% had ischemic cerebrovascular events over
               ¼ of these events strokes (5.5%)
             – At 2 years 22% had ischemic cerebrovascular events

             – In patients with less than 75% stenosis
                      • 1 year 3%
                      • 2 years 6%
Chambers BR, Norris JW. Outcome in patients with asymptomatic neck bruits. N Engl J Med 1986;315:860-865
   Outcome in patients with
asymptomatic neck bruits 1986
• What is the risk of stroke with asymptomatic
  carotid stenosis?
  – With ≥ 75% asymptomatic stenosis, 22% of
    patients will have an ischemic cerebrovascular
    event at 2 years
• What can we do about it?
                                   Medical Treatment
• Both systolic and diastolic blood pressure
  independently related to stroke incidence
       – 6mm reduction in DBP produces 42% reduction in
         stroke rate
       – Tx of isolated systolic hypertension in patients over 60
         reduces stroke incidence by 32%
• Smoking cessation
       – Relative risk 1.5-2.2
• Serum lipid levels
       – have not been shown to affect stroke rate but low
         levels slow progression of atherosclerosis
 Biller J, Feinberg WM, Castaldo JE, et al. Guidelines for carotid endarterectomy: a statement for healthcare professionals from a special writing
 group of the stroke council, american heart association. Circulation 1998;97:501-509
                              Medical Treatment
• Alcohol consumption
  – Heavy alcohol use associated with excessive stroke
    risk
  – Moderate consumption may have no or a slightly
    protective effect
• Antiplatelet therapy
  – 23% reduction in stroke with aspirin compared to
    placebo in patients with history of TIA/stroke
  – Also 22% reduction in MI/death
  Biller J, Feinberg WM, Castaldo JE, et al. Guidelines for carotid endarterectomy: a statement for healthcare professionals from a special writing
  group of the stroke council, american heart association. Circulation 1998;97:501-509
                        CEA
• Carotid Endarterectomy
  – Surgical removal of the inner layer of the carotid
    artery when narrowed by atheromatous intimal
    plaques
                      1953
• KJ Strully attempted
  (unsuccessfully) to
  operate on an occluded
  carotid artery.
                                                            1954
• First successful extra
  cranial carotid surgery
  preformed by Felix
  Eastcott.
• Patient with episodes of
  hemispheric cerebral
  ischemic attacks and an
  atherosclerotic lesion at
  the carotid bifurcation.
• Treated with resection
  and primary
  anastomosis.

Eastcott HHG, Pickering GW, Rob CG. Reconstruction of internal carotid artery in a patient with intermittent attacks of hemiplegia. Lancet
1954;2:994-6.
                        1953?
• Michael DeBakey
  published a similar
  operative case preformed
  prior to Eastcott’s case.
• However his report was
  published after Eastcott’s
  case and thus Eastcott is
  credited with bringing the
  possibility of carotid
  artery repair to medical
  attention.
                   1966

• Drs. Stanley Crawford and Michael DeBakey
  credited with first describing carotid
  endarterectomy in 1966. (although DeBakey
  claimed to have preformed it in 1953)
Cooley
   • Dr. Denton Cooley is
     credited with being the
     first to use an
     intravascular shunt
     during carotid surgery
   • Professional rivalry
     with DeBakey that
     lasted 40 years, made
     public amends
     November 7, 2007 at
     ages 99 and 87
Cooley
   • When asked by a Lawyer
     if he considered himself
     the best heart surgeon in
     the world he answered in
     the affirmative.
   • The lawyer then asked if
     he thought he was being
     rather immodest?
   • Cooley replied, “Perhaps,
     but remember I am under
     oath.”
• Does medical therapy decrease risk of stroke?
  – Smoking cessation, BP control, etoh in moderation
    and antiplatelet therapy all reduce stroke risk
• What about CEA?
                                             NASCET 1991
• North American Symptomatic Carotid Endarterectomy Trial (50
  centers US and Canada)
   – TIA or non disabling stroke within 120 days with 30-99% stenosis
   – Patients randomized to medical or surgical therapy
   – Patients symptomatic with high grade lesions
     (70 - 99% stenosis), 659 patients, <80 years old
   – Results
               • 24% medically managed patients had stroke within 18 months
               • 7% surgical patients had a stroke
       – Rate of perioperative major stroke/death was 2.1% in this trial



Nascet C. Beneficial effect of carotid endarterectomy in symptomatic patients with high-grade carotid stenosis. North American Symptomatic Carotid
Endarterectomy Trial Collaborators. N Engl J Med 1991;325:445-53
                  NASCET 1991
• Study stopped early
• Risk reduction at 2 years
   – 12% 70-79% stenosis
   – 18% 80-89% stenosis
   – 26% 90-99% stenosis
• Conclusion
   – CEA highly beneficial to patients with recent
     hemispheric and retinal transient ischemic attacks or
     non disabling strokes and ipsilateral high-grade
     stenosis (70-99%) of the internal carotid artery.
              Carotid endarterectomy and
           prevention of cerebral ischemia in
           symptomatic carotid stenosis 1991
  • 189 symptomatic patients >50% ipsilateral
    stenosis at 16 VA hospitals
  • Randomized to CEA or medical management
  • At 1 year
           – 7.7% stroke/TIA rate in CEA group
           – 19.4% stroke/TIA rate in medical group


Mayberg MR, Wilson SE, Yatsu F, et al. Carotid endarterectomy and prevention of cerebral ischemia in symptomatic carotid stenosis. JAMA 1991;266:3289-
3294.
                  NASCET 1998
• Does CEA benefit symptomatic pts with
  stenosis <70%
• Any ipsilateral stroke at 5 years
  – 50-69% stenosis
     • 15.7% CEA
     • 22.2% medical
  – <50% stenosis
     • 14.9% CEA
     • 18.7% medical (not statistically significant)
               NASCET 1998
• CEA in symptomatic patients with 50-69%
  yields only moderate reduction in risk of
  stroke and provided no benefit to patients
  with <50% stenosis.
• Patients with ≥70% stenosis had durable
  benefit at eight years.
• Can CEA reduce the stroke risk in symptomatic
  patients?
  – CEA reduces the risk of any stroke from 25% to
    10% at two years in patients with symptomatic
    stenosis of ≥ 70% (NASCET)
• Can CEA reduce the stroke risk in
  asymptomatic patients?
               Veterans Affairs Trial, 1993
• Asymptomatic Carotid Stenosis Veterans
  Administration Study
     – 11 centers, 1983-1991
     – 444 men with asymptomatic carotid stenosis
     – 50% stenosis or more (angiogram)
     – Evaluated combined incidence of TIA, Amaurosis
       Fugax, and stroke
     – Randomized to optimal medical treatment alone
       vs. optimal medical treatment plus carotid
       endarterectomy
Hobson RW 2nd, Weiss DG, Fields WS, Goldstone J, Moore WS, Towne JB, Wright CB. Efficacy of carotid endarterectomy for asymptomatic carotid
stenosis. The Veterans Affairs Cooperative Study Group. N Engl J Med. 1993 Jan 28;328(4):221-7.
      Veterans Affairs Trial, 1993
• All patients followed for an average of 48
  months
• Incidence of ipsilateral neurologic events
  – 8% CEA
  – 20.6% medical group
• Stroke/death rate within 30 days not different
  between groups
  Veterans Affairs Trial, 1993




Incidence of Neurologic End Points for Ipsilateral Events.
Veterans Affairs Trial, 1993




Kaplan-Meier Curves for Event-free Rates of First Ipsilateral Stroke and
Transient Ischemic Attack Including Transient Monocular Blindness.
                                                     ACAS, 1995
  • Asymptomatic Carotid Artery Study
           – Prospective randomized trial
           – 39 sites in the US and Canada
           – 1987-1993, 1662 patients with asymptomatic
             carotid artery stenosis 60% or greater
           – Daily aspirin administration and medical risk factor
             management for all patients
           – Medical vs. carotid endarterectomy
Executive Committee for the Asymptomatic Carotid Atherosclerosis Study. Endarterectomy for Asymptomatic Carotid Artery Stenosis. JAMA, 273(18), 10
May 1995, pp 1421-1428
                   ACAS, 1995
• Outcomes
  – Cerebral infarction occurring in the distribution of
    the study artery, any stroke or death
  – Perioperative risk
     • 30 days post op 2.3% in the surgery group
     • 42 days post randomization 0.4% in the medical group
  – Median follow-up 2.7 years
  – Combined risk of outcomes
     • 5.1% CEA
     • 11% medical management
ACAS, 1995
ACAS, 1995
ACAS, 1995
• Can CEA reduce the stroke risk in
  asymptomatic patients?
  – CEA reduces the risk of any stroke or death from
    11% to 5% at five years in patients with
    asymptomatic stenosis of ≥ 60% (ACAS)
• What about stenting?
  Carotid angioplasty and stenting
• The first case reports of carotid artery
  angioplasty were reported in the early 1980s.
        Carotid angioplasty and stenting
  • The first large series of carotid angioplasty and
    stenting was reported by Roubin et.al. in 1996
         – They preformed angioplasty in 107 patients
           deemed too medically/anatomically unstable to
           undergo endarterectomy.
         – 10% combined stroke/death rate




Roubin GS, Yadav S, Lyer SS, et al. Carotid stent supported angioplasty: a neurovascular intervention to prevent stroke. Am J Cardiol
              1996;78:8-12.
  Carotid angioplasty and stenting
• In 2000 a large multicenter report (14 groups)
  in which 358 arteries in 338 patients with
  restenosis after CEA was published.
    – 5 year follow-up
    – Stroke rate 3.7%
    – Mortality 1.1%
    – Adverse events 4%


 New G, Roubin GS, Iyer SS, et al. Safety, efficacy, and durability of carotid artery stenting for restenosis following carotid endarterectomy: a
 multicenter study. J Endovascul Ther 2000;7:345-352.
        Carotid angioplasty and stenting
  • In 2001 Mathias et al. presented data on over
    3,000 carotid artery stents (CAS).
         – Stroke rate 2%
         – Complication rate 3%


  • These and other series demonstrated that
    stenting could be preformed with an
    acceptable complication rate.
Mathias K, Jager H, Hennigs S, et al. Endoluminal treatment of internal carotid artery stenosis. World J Surg 2001;25:328-334.
• What about stenting?
  – Large series of CAS have shown that stenting can
    be preformed with an acceptable complication
    rate
• But is stenting equivalent to CEA?
• 3 types of studies available to review efficacy
  of stenting
  – Case series
  – Industry sponsored registries
  – Randomized trials
In
                  Case Series
•   51% patients symptomatic
•   >97% successfully stented
•   64% evaluated by neurologist
•   After 2002 embolic protection devices (EPDs)
    widely utilized
                Filters
• Filter wire

• Interceptor

• Angioguard

• Accunet

• Emboshield
                Case Series
• Stroke rate 1% - 8% (lower with experience
  and EPD use)
• Overall 30 day stroke rate 3%
• Overall 30 day stroke/MI/death rate 4%
• Early restenosis rates 1%-8% (reported in half
  the series)
Industry-sponsored registries of CAS
 Industry-sponsored registries of CAS
• Presented at national meetings but not
  published in peer reviewed journals
• 30 day stroke rates 2%-7%
• 30 day stroke, MI, death rates 3%-8%
• 27% of patients symptomatic
Randomized trials CAS vs. CEA
           Randomized trials
• All used independent neurologist
  examinations
• After 2001, all used EPDs
                                             CARESS 2003
    • Not really a randomized trial
            – CARESS assigned patients to CAS or CEA based on
              “selection criteria reflective of broad clinical
              practice”
                   • Equivalence cohort
                   • 397 patients




CARESS Steering Committee. Carotid Revascularization Using Endarterectomy or Stenting Systems (CARESS): Phase I Clinical Trial. J
Endovasc Ther 2003;10:1021-1030
                                             CARESS 2003
    •     CEA vs. CAS with embolic protection
    •     ≥ 50% symptomatic stenosis
    •     ≥ 75% asymptomatic stenosis
    •     30 day mortality, stroke and MI rate
            – CEA 3%
            – CAS 2%
    • 30 day mortality and stroke rate
            – CEA 2%
            – CAS 2%

CARESS Steering Committee. Carotid Revascularization Using Endarterectomy or Stenting Systems (CARESS): Phase I Clinical Trial. J
Endovasc Ther 2003;10:1021-1030
                                             CARESS 2003
    • Lowest stroke/complication rates for both CAS
      and CEA across all trials
            – Careful patient selection may be one of the most
              important determinants of outcome for both CAS
              and CEA




CARESS Steering Committee. Carotid Revascularization Using Endarterectomy or Stenting Systems (CARESS): Phase I Clinical Trial. J
Endovasc Ther 2003;10:1021-1030
                                              SAPPHIRE 2004
  • Stenting and Angioplasty with Protection for
    Patients at HIgh Risk for Endarterectomy
    (SAPPHIRE) trial
           – Data at 30 days and 1 year
           – EPDs used on all patients
           – 334 patients
           ≥ 50% symptomatic stenosis
           ≥ 80% asymptomatic stenosis

Yadav JS, Wholey MH, Kuntz RE, et al. Protected carotid artery stenting verses endarterectomy in high-risk patients. N Engl J Med 2004; 351:1493-1501.
                                      SAPPHIRE 2004
• Stenting and Angioplasty with Protection for
  Patients at HIgh Risk for Endarterectomy
  (SAPPHIRE) trial
   – Data at 30 days and 1 year
   – EPDs used on all patients
   – 334 patients
   ≥ 50% symptomatic stenosis
   ≥ 80% asymptomatic stenosis

  Yadav JS, Wholey MH, Kuntz RE, et al. Protected carotid artery stenting verses endarterectomy in high-risk patients. N Engl J Med 2004;
  351:1493-1501.
                                              SAPPHIRE 2004
  • SAPPHIRE
           – High risk for CEA
                    •   Clinically significant heart disease
                    •   Severe pulmonary disease
                    •   Contralateral carotid occlusion
                    •   Contralateral laryngeal nerve palsy
                    •   Previous radical neck surgery or radiation therapy
                    •   Recurrent stenosis after CEA
                    •   Age > 80 years

Yadav JS, Wholey MH, Kuntz RE, et al. Protected carotid artery stenting verses endarterectomy in high-risk patients. N Engl J Med 2004; 351:1493-1501.
                                              SAPPHIRE 2004
  • SAPPHIRE
           – High risk for CEA
                    •   Clinically significant heart disease
                    •   Severe pulmonary disease
                    •   Contralateral carotid occlusion
                    •   Contralateral laryngeal nerve palsy
                    •   Previous radical neck surgery or radiation therapy
                    •   Recurrent stenosis after CEA
                    •   Age > 80 years

Yadav JS, Wholey MH, Kuntz RE, et al. Protected carotid artery stenting verses endarterectomy in high-risk patients. N Engl J Med 2004; 351:1493-1501.
                                      SAPPHIRE 2004
 • SAPPHIRE
        – Randomized to CEA or CAS
        – 30 day stroke/MI/death rate
                • 4.4% CAS
                • 9.8% CEA
        – 1 year stroke/MI/death rate
                • 12% CAS
                • 20% CEA
        – High rates in CEA group secondary to high risk
          patients
        – Conclusion CAS with EPD not inferior to CEA in high
          risk patients
Yadav JS, Wholey MH, Kuntz RE, et al. Protected carotid artery stenting verses endarterectomy in high-risk patients. N Engl J Med
2004; 351:1493-1501.
                                     SAPPHIRE 2004
• Flaws with SAPPHIRE
      – Supported by Cordis Corp. manufacturer of stent used in
        study (Smart stent with Angioguard)
      – 747 pts evaluated only 334 randomized (406 entered into
        stent registries, 7 referred for CEA)
      – Stopped after 334 pts out of planned 2,900 pts enrolled
        due to “competing nonrandomized registries”
      – Troponin based MI
              • “non-Q-wave MI have 27 fold increased risk of MI in the next 6
                months”
              • This was not borne out in the long-term outcomes

Gurm, HS, Yadav JS, Fayad, P M.D.et.al.Long-Term Results of Carotid Stenting versus Endarterectomy in High-Risk
Patients. N. Engl. J. Med. 2008;358:1572-9
               SAPPHIRE 2004
• SAPPHIRE was used to gain FDA approval of
  the Cordis stent
  – 6 cardiologists, 2 interventional radiologists, 2
    vascular surgeons, 1 neurologist on panel
  – Approved 6 to 5
                SAPPHIRE 2008
• 3 year data, primary endoints plus death or
  ipsilateral stroke at 3 years
  – 24.6% CAS
  – 26.9% CEA
• 15 strokes in each group
  – 11 ipsilateral in the CAS group
  – 9 ipsilateral in the CEA group
• Conclusion – no difference in longterm
  outcome
                                          SPACE 2006
• Stent-Supported Percutaneous Angioplasty of the
  Carotid Artery vs. Endarterectomy (SPACE)
  collaborative group
     – Hypothesis was “that carotid-artery stenting is not
       inferior to carotid endarterectomy for the treatment
       of severe symptomatic carotid stenosis”
     – Endpoints
            • Ipsilateral stroke, intracerebral bleeding, or death within 30
              days
     – 1,183 symptomatic patients randomized to CAS or CEA
            • ≥ 50% stenosis
            • Low risk surgical patients

Group SC, Ringleb PA, Allenberg J, et al. 30 day results from the SPACE trial of stent-protected angioplasty verses carotid
endarterectomy in symptomatic patients: a randomised noninferiority trial. Lancet 2006;368:1239-1247.
                                          SPACE 2006
     – Rate of death/ipsilateral stroke at 30 days
            • 6.84% CAS
            • 6.34% CEA
     – Had same stroke/death rate in patients treated with
       and without embolic protection (27% of stented
       patients had EPD)
     – Stroke rate with continued deficits
            • 4% CAS
            • 2.9% CEA
     – Conclusion failed to prove noninferiority of CAS vs CEA

Group SC, Ringleb PA, Allenberg J, et al. 30 day results from the SPACE trial of stent-protected angioplasty verses carotid
endarterectomy in symptomatic patients: a randomised noninferiority trial. Lancet 2006;368:1239-1247.
1. Age >75 higher risk both CEA and CAS but increased more in CAS group
2. Female patients higher risk in CAS group
1. Age >75 higher risk both CEA and CAS but increased more in CAS group
2. Female patients higher risk in CAS group
                                              EVA-3S 2006
   • Endarterectomy vs. Angioplasty in Patients with
     Symptomatic Severe carotid Stenosis (EVA-3S) (Paris)
           – 527 high-risk patients with ≥ 60% symptomatic stenosis
           – randomized to CAS or CEA
           – 30 day stroke/death rate
                  • 3.9% CEA
                  • 9.6% CAS
           – 6 month stroke/death rate
                  • 6.1% CEA
                  • 11.7% CAS
   • Conclusion stroke/death rate after CEA lower than after
     CAS in this population.
   • Study stopped early for “reasons of safety and futility”

Mas J-L, Chatellier G, Beyssen B, et al. Endarterectomy versus stenting in patients with symptomatic severe carotid stenosis. N Engl J
Med 2006;355:1660-1671.
EVA-3S
EVA-3S
                                               CREST 2004
   • Carotid Revascularization Endarterectomy vs.
     Stenting Trial (CREST)
           – Randomized trial CEA vs. CAS in low risk patients with
             symptomatic ≥ 50% stenosis and asymptomatic ≥ 70%
             stenosis
           – Lead in phase of this study
                  • 749 patients underwent CAS (31% symptomatic)
                  • 30 day stroke/death rate higher with age ≥ 80 years
                         – 12.1% in patients ≥ 80 years
                         – 3.2% in patients < 80 years
   • Care should be taken when CAS is preformed on
     elderly patients
Hobson RW, Howard VJ, Roubin GS, et al. Carotid artery stenting is associated with increased complications in octogenarians: 30-
day stroke and death rates in the CREST lead-in phase. J Vasc Surg 2004; 40:1106-1112
CREST 2004
                    CREST 2010
• On February 26, 2010 presented results at the
  American Stroke Association’s Annual
  International Stroke Conference
• Now 2,502 patients at 2.5 years
  – Stroke rate
     • CEA 2.3%
     • Stent 4.1%
  – MI rate (don’t state criteria for MI)
     • CEA 2.3%
     • Stent 1.1%
                  CREST 2010
• "The data from the landmark CREST trial has shown
  that there was no difference between CAS and CEA in
  this large group of symptomatic and asymptomatic
  patients. From a practitioner's point of view, we and
  our patients now have a choice in terms of what
  type of revascularization therapy might be best for
  them," said Barry Katzen, MD, Founder and Medical
  Director of Baptist Cardiac and Vascular Institute and
  Clinical Professor of Radiology at the University of
  South Florida College of Medicine in Florida.
                 CREST 2010
• Christopher J. White, MD, Chairman,
  Department of Cardiovascular Diseases,
  Ochsner Clinic Foundation in New Orleans,
  Louisiana said, "I think this is clearly a game
  changer for carotid stenting. It is going to
  bring reimbursement. It is going to bring
  choice for our patients, especially in the
  seniors (the Medicare population) who are
  being forced to have surgery. I think many
  good things are going to come out of this."
                           ICSS 2009
• International Carotid Stenting Study (ICSS)
     – Randomized 1710, ≥ 50% stenosis, symptomatic
       patients
     – 30 day safety data showed
           • Twice as many strokes for CAS vs. CEA ( 7.0% vs. 3.3%)
           • Confirmed by blinded MRI
           • any stroke, death or perio‐op MI, CAS vs. CEA (8.5% vs.
             5.1%)
           • presented to the ICSS Investigators Meeting on
             05/22/09
     – Awaiting longterm results
http://www.cavatas.com/
                             ACT I
• Asymptomatic Carotid Trial (ACT I)
   – Randomize asymptomatic patients standard risk
     for surgery
   – ≥ 70% stenosis
   – Currently enrolling patients




  http://www.act1trial.com
                    High     30 day 30 day Long term             Long term
                    risk      CAS    CEA      CAS                   CEA
Sapphire (1 yr)      Yes      4.4%       9.8%         12%          20%
    Space            No       6.8%       6.3%          4%           2.9%
EVA-3S (6 mo)        Yes      9.6%       3.9%         12%            6%
Crest (2.5 yrs)      No                            Stroke 4%     Stroke 2%
                                                     MI 1%         MI 2%
     ICSS            No       8.5%         5.1


     Primary outcomes for various trials peri op and long term
        FDA Approved Devices
• SAPPHIRE trial by Cordis
  – FDA approval of angioguard system in April 2004
• ARCHeR registry by Guidant
  – FDA approval for Accunet/Acculink system in
    August 2004
• SECURITY registry by Abbott
  – FDA approval for Xact/Emboshield system in
    September 2005
Accunet/Acculink system
Xact/Emboshield system
        FDA Approved Devices
• Symptomatic patients with ≥ 50% ICA stenosis
  or asymptomatic patients with ≥ 80% ICA
  stenosis
• Patients must also be considered high risk for
  CEA
        FDA Approved Devices
• Symptomatic patients with ≥ 50% ICA stenosis
  or asymptomatic patients with ≥ 80% ICA
  stenosis
• Patients must also be considered high risk for
  CEA
                “High risk for CEA”
• High medical risk
   –   Severe coronary artery disease
   –   Severe pulmonary disease
   –   End stage renal disease
   –   Uncontrolled diabetes
• High anatomic risk
                “High risk for CEA”
• High medical risk
   –   Severe coronary artery disease
   –   Severe pulmonary disease
   –   End stage renal disease
   –   Uncontrolled diabetes
• High anatomic risk
   –   Contra lateral ICA occlusion
   –   Radiation therapy to the neck
   –   Distal ICA stenosis
   –   Spinal immobility
   –   Tracheostomy
   –   Contra lateral laryngeal nerve paralysis
Medicare/Medicaid Reimbursement
Medicare/Medicaid Reimbursement
 Medicare/Medicaid Reimbursement
• Only FDA approved devices
• Only treatment of symptomatic, high risk
  patients with > 70% stenosis in
  Medicare/Medicaid approved centers
• Will reimburse for high risk symptomatic
  patients with 50-69% stenosis and
  asymptomatic patients with > 80% stenosis
  only if enrolled in an approved clinical trial
            So what do we know?
• Is TIA a risk factor for stroke?
   – 33% of TIA patients will suffer a stroke within 5 years, 17%
     within 1 year
• What about asymptomatic carotid stenosis?
   – With ≥ 75% asymptomatic stenosis, 22% of patients will have an
     ischemic cerebrovascular event at 2 years
• Does medical therapy decrease risk of stroke?
   – Smoking cessation, BP control, etoh in moderation and
     antiplatelet therapy all reduce stroke risk
• Can CEA reduce the stroke risk in symptomatic patients?
   – CEA reduces the risk of any stroke from 25% to 10% at two years
     in patients with symptomatic stenosis of ≥ 70% (NASCET)
• Can CEA reduce the stroke risk in asymptomatic patients?
   – CEA reduces the risk of any stroke or death from 11% to 5% at
     five years in patients with asymptomatic stenosis of ≥ 60%
     (ACAS)
             So what do we know?
• What about stenting?
   – Large series of CAS have shown that stenting can be preformed with
     an acceptable complication rate
• But is stenting equivalent to CEA?
   – Current evidence does not support a change from the
     recommendation of carotid endarterectomy as the standard of care
     for carotid stenosis
• Has the FDA approved any stent systems? Does Medicare
  pay for stenting?
   – Three FDA approved stents, only for symptomatic patients with ≥ 50%
     ICA stenosis or asymptomatic patients with ≥ 80% ICA stenosis, also
     must be considered high risk for CEA
   – Medicare only pays for stenting of symptomatic > 70% stenosis outside
     of trials
             So what do we know?
• What about stenting?
   – Large series of CAS have shown that stenting can be preformed with
     an acceptable complication rate
• But is stenting equivalent to CEA?
   – Current evidence does not support a change from the
     recommendation of carotid endarterectomy as the standard of care
     for carotid stenosis
• Has the FDA approved any stent systems? Does Medicare
  pay for stenting?
   – Three FDA approved stents, only for symptomatic patients with ≥ 50%
     ICA stenosis or asymptomatic patients with ≥ 80% ICA stenosis, also
     must be considered high risk for CEA
   – Medicare only pays for stenting of symptomatic > 70% stenosis outside
     of trials
                Conclusions
• As with other minimally invasive surgical
  procedures, CAS has developed rapidly over
  the last decade
• Equivalence with CEA has been established
  only in high-risk patients?
• The effectiveness in lower-risk patients has
  not yet been determined
                 Conclusions
• The choice of CAS vs. CEA is primarily based on
  individual practitioner experience rather than on
  clear evidence-derived guidelines
• Increased utilization of CAS has been promoted
  by the popularity of “minimally invasive
  procedures” as well as the marketing of CAS
  system developers
• Ongoing randomized trials will help determine
  optimal carotid revascularization strategies in the
  future
Questions?
•
                                                         References
    Roubin GS, Yadav S, Lyer SS, et al. Carotid stent supported angioplasty: a neurovascular intervention to prevent stroke. Am J Cardiol 1996;78:8-12.
•   Mathias K, Jager H, Hennigs S, et al. Endoluminal treatment of internal carotid artery stenosis. World J Surg 2001;25:328-334.
•   Yadav JS, Wholey MH, Kuntz RE, et al. Protected carotid artery stenting verses endarterectomy in high-risk patients. N Engl J Med 2004; 351:1493-1501.
•   Group SC, Ringleb PA, Allenberg J, et al. 30 day results from the SPACE trial of stent-protected angioplasty verses carotid endarterectomy in symptomatic patients: a
    randomised noninferiority trial. Lancet 2006;368:1239-1247.
•   Mas J-L, Chatellier G, Beyssen B, et al. Endarterectomy versus stenting in patients with symptomatic severe carotid stenosis. N Engl J Med 2006;355:1660-1671.
•   CARESS Steering Committee. Carotid Revascularization Using Endarterectomy or Stenting Systems (CARESS): Phase I Clinical Trial. J Endovasc Ther 2003;10:1021-1030
•   Hobson RW, Howard VJ, Roubin GS, et al. Carotid artery stenting is associated with increased complications in octogenarians: 30-day stroke and death rates in the
    CREST lead-in phase. J Vasc Surg 2004; 40:1106-1112
•   http://www.cavatas.com/
•    http://www.ptca.org/pr_abbott/20050118.html
•   Kastrup A, Gröschel K, Krapf H, Brehm BR, et al. Early Outcome of Carotid Angioplasty and Stenting With and Without Cerebral Protection Devices: A Systematic
    Review of the Literature. Stroke 2003;34:813-819
•   http://www.cardiologytoday.com/view.aspx?rid=33027
•   http://www.invatec.com/tool/home.php?s=0,1,55,59,204
•   Hart JP, Peeters P, Verbist J, et al. Do device characteristics impact outcome in carotid artery stenting? J Vasc Surg 2006:44;725-730
•   Crawford ES, DeBakey ME, Garrett HE, Howell J. Surgical treatment of occlusive cerebrovascular disease. Surg Clin North Am. 1966;46:873-884
•   Cooley DA, Al-Naamanyd, Carton CA. Surgical treatment of arteriosclerotic occlusion of common carotid artery. J Neurosurg. 1956;13:500-506
•   Mayberg MR, Wilson SE, Yatsu F, et al. Carotid endarterectomy and prevention of cerebral ischemia in symptomatic carotid stenosis. JAMA 1991;266:3289-3294.
•   http://www.cdc.gov/
•   Biller J, Feinberg WM, Castaldo JE, et al. Guidelines for carotid endarterectomy: a statement for healthcare professionals from a special writing group of the stroke
    council, american heart association. Circulation 1998;97:501-509
•   Stoner MC, Abbott WM, Wong DR, et al. Defining the high risk patient for carotid endarterectomy: an analysis of the prospective National Surgical Quality
    Improvement Program database. J Vasc Surg 2006;43:285-295.
•   New G, Roubin GS, Iyer SS, et al. Safety, efficacy, and durability of carotid artery stenting for restenosis following carotid endarterectomy: a multicenter study. J
    Endovascul Ther 2000;7:345-352.
•   Nascet C. Beneficial effect of carotid endarterectomy in symptomatic patients with high-grade carotid stenosis. North American Symptomatic Carotid
    Endarterectomy Trial Collaborators. N Engl J Med 1991;325:445-53
•   Hobson RW 2nd, Weiss DG, Fields WS, Goldstone J, Moore WS, Towne JB, Wright CB. Efficacy of carotid endarterectomy for asymptomatic carotid stenosis. The
    Veterans Affairs Cooperative Study Group. N Engl J Med. 1993 Jan 28;328(4):221-7.
•   Executive Committee for the Asymptomatic Carotid Atherosclerosis Study. Endarterectomy for Asymptomatic Carotid Artery Stenosis. JAMA, 273(18), 10 May 1995,
    pp 1421-1428
•   Gray WA, Hopkins LN, Yadav S, Thomas D, et al. Protected carotid stenting in high-surgical-risk patients: The ARCHeR results. J Vasc Surg 2006;44:258-69.
•   Eastcott HHG, Pickering GW, Rob CG. Reconstruction of internal carotid artery in a patient with intermittent attacks of hemiplegia. Lancet 1954;2:994-6.
•   Gurm, HS, Yadav JS, Fayad, P M.D.et.al.Long-Term Results of Carotid Stenting versus Endarterectomy in High-Risk Patients. N. Engl. J. Med. 2008;358:1572-9
• Multiple reports on CEA stroke/death rates for
  octogenarians reveal no increased risk at 30
  days vs. younger population (1.9-4.4% vs 1.7-
  4.2%)
• However multiple reports on CAS seem to
  suggest a much higher rate of 30 day stroke,
  mi and death in this population (25%
  compared to 8.2%)
• Yet other reports show no difference
                                      High risk patients
• Multiple studies show a
  30 day stroke rate of 1-
  2% even in high risk
  patients with CEA
• CEA may be performed
  under local anesthesia
  with a significant
  reduction in
  stroke/mortality/MI in
  high risk patients
Stoner MC, Abbott WM, Wong DR, et al. Defining the high risk patient for carotid endarterectomy: an analysis of the prospective National Surgical
Quality Improvement Program database. J Vasc Surg 2006;43:285-295.
Non-Filter Embolic Protection Devices
• Balloons
• Flow reversal devices
        Guardwire by Medtronic
• Balloon placed distal to
  lesion for transient
  occlusion during
  angioplasty/stent
  placement
• Allows recovery of any
  liberated plaque by
  aspiration before
  restoration of antegrade
  flow
• May form distal thrombus
• Originally developed for
  coronary stent placement
                                 MOMA Device
• Invatec device
• ARMOUR trial to be completed in 2009.
     – 25 U.S. and European sites
     – hope for FDA approval by the end of 2009

                                                       Balloon in external carotid

                                                       Stent placement and aspirate
                                                       debris through port

                                                       Balloon in common carotid

http://www.cardiologytoday.com/view.aspx?rid=33027
http://www.invatec.com/tool/home.php?s=0,1,55,59,204
           Parodi Device by Gore
• Reversing of blood flow at the treatment site
• Liberated emboli directed away from the brain
• Selective occlusion of the common carotid and external
  carotid arteries
• Shunt between the carotid artery and femoral vein
• Blood from the opposite side of the brain via the Circle
  of Willis and collateral vessels is redirected to the lower
  pressure venous return
• Embolic particles are captured in a filter outside the
  body.
Parodi Device by Gore
         Parodi Device by Gore
• EMPiRE (Embolic Protection with flow
  Reversal) Clinical Study
  – Started July 2006
  – designed to demonstrate the safety and efficacy of
    the GORE Neuro Protection System when used for
    embolic protection during carotid artery stenting
    procedures
                                                          EPDs
   • 2003 review of the literature by Kastrup found
          – A 3-fold increased rate of 30 day stroke/death without
            protection compared with protection.
          – A 6-fold increase of minor stroke within 30 days of CAS
            without protection compared with protection.


                                                                                                       Without          With EPD
                                                                                                       EPD
                                                                                                       3.7%             0.55%
                                                                                                       1.1%             0.33%
                                                                                                       0.71%            0.89%
                                                                                                       5.5%             1.8%

Kastrup A, Gröschel K, Krapf H, Brehm BR, et al. Early Outcome of Carotid Angioplasty and Stenting With and Without Cerebral
Protection Devices: A Systematic Review of the Literature. Stroke 2003;34:813-819
                    Stent Design
• Open Cell more flexible
   – conforming




• Closed Cell stiffer
   – Scaffold and support
     fractured plaque better
   – Keep thrombogenic
     material away from lumen
                      Filter Design
• Eccentric filters
   – Filter placed
     eccentrically on wire
   – Better wall apposition
     leads to better TIA
     prevention


• Concentric filters
   – Filter placed
     concentrically on wire
        FDA Approved Devices
• FDA approval compared CAS system to
  estimated CEA 30 day stroke/death/MI and 1
  year ispsilateral stroke rates in high risk
  patients of 14.5%.
Hart JP, Peeters P, Verbist J, et al. Do device characteristics impact outcome in carotid artery stenting? J Vasc Surg 2006:44;725-730
                                                           ARCHeR




Gray WA, Hopkins LN, Yadav S, Thomas D, et al. Protected carotid stenting in high-surgical-risk patients: The ARCHeR results. J Vasc Surg 2006;44:258-69.
ACAS, 1995

				
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