Carotid Artery Disease

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SVS Clinical Research
Priorities: Carotid
Disease
John J Ricotta MD FACS
Background: Public Health Impact
(AHA Heart Disease and Stroke Statistics 2011 Update,
Circ 2011;123: e18-e209)
7M strokes, 13M silent infarctions
 795k strokes/yr – 610k new, 185k recurrent
- 87% (690k) ischemic (140-200k CAD)
- 2/3 unheralded
- 150k fatal (16.7% of all CVD)
- 15-30% survivors permanent serious
disabled, only 1/3 completely recover
 250-500 K TIA/yr – 17% stroke w/in 90 days
 Early RX of TIA/Stroke reduces death and
disability from recurrence
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Background: Imaging
CDUS preferred for initial imaging
 No agreement on best imaging protocols
CDUS, CTA, MRA, DSA
 Neck imaging not routinely incorporated
into acute stroke protocols
 No agreement on role of imaging in
asymptomatic patients
 No agreement on follow up protocols
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Background: Therapy
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CEA beneficial for Sx and Asx CS
CAS beneficial for Sx pts
CEA decreasing CAS increasing
86% /14%
CREST: CEA reduced stroke/death
CAS reduced MI
Composite endpoints equivalent
90% of Interventions on Asymptomatic pts.
NNT 16-19
Role of BMT?
CEA vs CAS Met Analysis
(Murad et al JVS 2011;53:792-7)
Background: Economic Impact
(AHA Heart Disease and Stroke Statistics 2011 Update,
Circ 2011;123: e18-e209)
Annual stroke Cost 40.8 Billion
-direct costs 25.2 Billion
 Lifetime Cost / stroke $140,048
 CEA cost effective even Asx pts
- low stroke rate, longevity and high
cost of stroke
 CEA more cost effective than CAS d/t
procedural costs ($4,000/ case)
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Background Economic Impact
Carotid and Neuroimaging costs are a significant
portion of health care costs
- CMS reimbursed 3m CDUS/yr
- CT/ MRI cost likely much more
 Defining appropriate algorithms for case finding
and follow up is important
 Identifying imaging protocols that identify stroke
prone lesions is important
-avoid unnecessary Interventions in Asx pts.
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Current Evidence
Review recent Guidelines from ASA/ACC/AHA
and SVS to Identify clinical issues that require
further study
 Review SVS Membership recommendations
 Issues divided based on several criterion
- Resource Utilization
- Patient Selection for Intervention
- Comparison of Alternative Therapies
- Conditions with little data to guide
treatment
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Guidelines: Imaging
No Benefit to population based Screening
- bruit alone not an indication
 High Risk screening may be indicated
- smokers, PVD, CAD (L main), age
>65, multiple factors increase yield
 F/U with disease or after intervention
indicated but no agreement on intervals or
what to do with pts who are “normal”
after intervention
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Guidelines: Imaging
Plaque character, surface ulceration, “hits” on
TCD, asymptomatic lesions on brain imaging all
associated with increased stroke risk
 Impression but no evidence that severity (60-79
vs. 80-99) of Asymptomatic Stenosis is related
to stroke risk
 Duplex, CT and MR all utilized to describe plaque
character but with inconsistent results
 Silent on imaging protocols in acute stroke
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Imaging in Acute Stroke Patients
“Brain attack” protocols focus on MRI with
intracranial MRA
-neck MRA or carotid duplex is not standard
 “Just in time” duplex not mentioned in patients
with ANS, EXPRESS data shows expedited
evaluation reduces recurrent Sxs
 This is inconsistent with recommendation for
early CEA in acute stroke patients
 Selection of therapy depends on distribution of
intracranial and extracranial disease
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Imaging Questions
When is screening Asymptomatic Pts for
CS indicated?
 How do we define “stroke prone” lesions?
 Impact of early duplex in TIA pts
 What imaging is needed in the acute
stroke patient IC vs EC ?
 What follow up is appropriate for CS or
after carotid intervention?
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Potential Studies
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Identify “high risk” subgroups to screen with
CDUS
Identify/ Compare reproducible, available
techniques to identify plaque and surface
characteristics to identify “high risk” lesions
Determine natural history of 60-79% vs 80-99%
stenosis
Evaluate “just in time” imaging in TIA pts
Evaluate yield of routine neck imaging in acute
stroke patients (race, age)
Utility of post intervention imaging
Guidelines: Patient Selection
Intervention for Sx > 50%, Asx >60%,
>70% provided AHA procedural
guidelines met
 CEA preferred to CAS in good risk pts.
 CAS preferred in High risk SX pts
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CAS an alternative in Sx and Asx pts
within AHA guidelines
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In Sx pts intervention preferred within 2
weeks of Symptoms
Guidelines: Patient Selection
Acknowledge the dysjunction of the
“composite” endpoints of stroke, death,
MI
 Definition of “Medical High Risk”
 Acknowledge need for Medical arm in
Asymptomatic patients
 Intervention for High Grade
recurrent stenosis despite poor data
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Guidelines Unanswered Questions
Definition of “High Risk” CAS / CEA pts
 Ideal stent , EPD
 Long term sequelae of “silent hits” on
MRI, chemical MI
 Recommendations on combined carotid
and coronary disease
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Patient Selection Questions
Medical Treatment vs intervention in Asx
pts. (2 ongoing trials underway)
 Long term cognitive impact of MRI lesions
 How to reduce MI in CEA and Stroke in
CAS
 What is contemporary CEA/CAS High Risk
 When to intervene in restenosis
 Carotid interventions in CABG pts
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Potential Studies
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CAS/CEA/Med Rx in asymptomatic pts
- can combine with lesion characterization
Long Term Cognitive Function CAS/CEA/BMT
Intervention vs observation in Asx restenosis
Role of Carotid Screening in CAD pts
-identify “high yield” group
Revascularization Strategies in CABG pts
-unilateral Asx >80%, b/l Asx >70%, Sx
>50% ( evaluate aortic arch)
Potential Studies
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How to improve results of Interventions
- Role of CAD screening in Asx CEA pts
- Role of anatomic selection in CAS
-“Learning curve” in CAS
- Influence of stent design, EPD type
in CAS
Guidelines: Insufficient Data to
Guide Treatment
Intervention in acute stroke
 Crescendo TIA
 Stroke in Evolution
 FMD - symptomatic and asymptomatic
 Carotid Dissection
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Questions
Define acute stroke pts who will benefit
from urgent/emergent intervention
-size infarct IC vs EC disease
 Treatment of SIE, Crescendo TIA
 Treatment for FMD – sx and asx
-observation, AP, AC, CAS
 Carotid dissection – if/when to intervene,
AC vs. AP
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Potential Studies
Urgent (<48hrs) vs. Early (<2wks)
intervention in acute stroke –role of brain
imaging and arterial anatomy in selection
 FMD – Asx: Antiplt vs. observation
Sx: Antiplt vs. CAS
 Dissection – AC vs. AP vs. CAS in
symptomatic pts
 Early intervention vs. Medical Rx for
Crescendo TIA and SIE, selection factors
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Priorities
CAS/CEA/BMT in Asymptomatic pts
 Optimal imaging protocols
 Improving results of Interventions
 Management of Pts with combined
disease, recurrent stenosis
 Management of Acute Neurological
Syndromes
 Unusual Conditions
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