Transcript Slide 1

 Learn neurology “stroke by stroke.” C.M.Fisher
History
 Wepfer was the first in 1658, to recognize the
significance of carotid obstruction and its relationship
to underlying "fibrous masses" and thrombus.
 It was Fisher who, in 1951, recognized that the two
basic mechanisms causing focal cerebral ischemia
from carotid artery disease were embolization,
decreased flow through the carotid arteries, or both.
 In 1954, Eastcott et al reported a successful operation
on a 66-year-old woman with recurrent transient
ischemic attacks (TIAs) and an angiographically
defined carotid stenosis.
Diagnosis of stroke
 The diagnosis of stroke is clinical and depends crucially on an
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accurate history, taken from the patient,carer or witness.
The neurological symptoms and signs are focal (i.e.
neuroanatomically localizing) rather than non-focal
The focal neurological symptoms are negative in quality
The onset of the focal neurological symptoms was sudden
The focal neurological symptoms were maximal at onset (i.e.
evolving over minutes in all of the affected body parts) rather
than progressive
Transient Ischemic Attack (TIA)
 Reversible focal dysfunction, usually lasts minutes
 Among TIA pts who go to ED:
 5% have stroke in next 2 days
 25% have recurrent event in next 3 months
 Stroke risk decreased with proper therapy
Stroke
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Stroke
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Risk Factor +
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b
a+b
Risk Factor -
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d
c+d
a+c
b+d
 Reletive Risk (RR)= a/a+b/c/c+d=a(c+d)/c(a+b)
 Odds ratio (OR)=a/b/c/d=ad/bc
Risk factors
 The proportion of ischemic stroke in the population
that can be attributed to a particular risk factor is
called the attributable risk (AR) .
 This equation shows the influence of both relative risk
and prevalence of the risk factor on the value of AR.
Carotid Artery Stenosias
 Patients were classified as symptomatic if they had a
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carotid distribution TIA or nondisabling stroke in the
preceding 6 months
In asymptomatic patients with stenosis < 80% and Aspirin
treatment only, there is 1% per year risk of stroke .
The risk of stroke in symptomatic patients treated with
antiplatelet therapy alone is thought to be 26% in 2 years.
Population-based studies indicate that the prevalence of
carotid stenosis is 0.5% by the sixth decade of life, but
increases to 10% by age 80 years
Extracranial internal carotid artery stenosis accounts for 15
to 20% of ischemic strokes
Prevention
 Absolute risk reduction
 Relative risk reduction
 Number need to treat
 Life expectency
 Procedure risk
 Subgroup analysis
Shall I ……………or shall I not?
symptomatic carotid stenosis
 North American Symptomatic Carotid
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Endarterectomy Trial (NASCET)
The European Carotid Surgery Trial (ECST)
The 2-year ipsilateral stroke risk in 70 to 99% stenosis
was 26% in the medically treated patients and 9% in
the BMT +CE group (p <0 .001).
The absolute risk reduction (ARR) was 17.0% and the
number needed to treat (NNT) was six at 2 years.
The greatest benefit found in men, patients above age
75 years, and those randomized within 2 weeks of their
last symptomatic event
symptomatic carotid stenosis
 Benefit for CE was shown for: 50 to 69% stenosis,
 ARR of 4.6% (over 5 years), NNT=22.
 No benefit in stenosis < 50%
symptomatic carotid stenosis
 A symptomatic carotid stenosis of 70 to 99 percent is a proven
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indication for CEA
The surgical risk should not exceed 6 %
The greatest benefit from CEA is likely to be achieved if surgery
takes place within two weeks of a nondisabling stroke or TIA.
It is recommended that the patient have at least a 5-year life
expectancy.
CEA is acceptable, but with a marginal to moderate degree of
benefit, for patients with symptomatic carotid stenosis of 50 to
69 percent (men who have surgery within two weeks of a
nondisabling stroke or TIA)
CE should not be considered for symptomatic patients with less
than 50% stenosis
Asymptomatic carotid disease
 The Asymptomatic Carotid Surgery Trial (ACST)
 The ACST showed that the net benefit of CEA is
delayed
 Seventeen patients need to be treated with CEA to
prevent 1 stroke over 5 years.
 Largest benefit is seen among men aged <65 years.
Asymptomatic carotid disease
 If CEA is considered for asymptomatic patients, the
potential benefit is most likely to be realized in:
 medically stable men with stenoses of 60 to 99
(especially 80 to 99)percent
 have a life expectancy of at least five years and
 treated by surgeons with a demonstrated perioperative
complication rate that is less than 3 percent
 The evidence supporting CEA in asymptomatic
women is less compelling.
Carotid artery stenting
 CAVATAS: The Carotid Artery Vertebral Artery
Transluminal Angioplasty Study (CAVATAS)
 SAPPHIRE: The Stenting and Angioplasty with
Protection in Patients at High Risk for Endarterectomy
(SAPPHIRE)
 EVA-3S: Endarterectomy versus Angioplasty in
Patients with Symptomatic Severe carotid Stenosis
 SPACE: Stent Protected Angioplasty versus Carotid
Endarterectomy (SPACE)
Risk of any stroke or death (%) within
30 days of treatment
acronym
Publication
date
Patients
Endovascular Surgical Notable
features
CAVATAS
2001
504
10%
9.9%
22%
stented. No
protection
SAPPHIRE
2004
307
4.8%
5.6%
Protection
devices in
100%
EVA-3S
2006
520
9.6%
3.9%
Protection
devices in
92%
SPACE
2006
1183
7.7%
6.5%
Protection
devices in
27%
Carotid artery stenting
 SAPPHIRE trial concluded that, among patients with severe
carotid-artery stenosis and coexisting conditions, carotid
stenting with the use of an emboli-protection device is not
inferior to carotid endarterectomy.
 SPACE failed to prove non-inferiority of carotid stenting
compared with endarterectomy.
 Ongoing trials include the North American CREST trial that is
randomizing patients with >50% symptomatic or >70%
asymptomatic carotid stenoses and the International Carotid
Stenting Study(ICSS or CAVATAS 2), which is randomizing
patients with symptomatic >70% carotid stenoses.
 While the durability of CEA is known, the long-term risk of
restenosis among stented patients is unclear
High Surgical Risk
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Clinically significant cardiac disease
Contralateral carotid occlusion
Severe pulmonary disease
Contralateral laryngeal-nerve palsy
Previous radical neck surgery or radiation therapy to
the neck
 Recurrent stenosis after endarterectomy
 High cervical lesion or low common carotid lesion
poorly accessible by surgery
 Severe tandem lesions and intracranial lesions
Conclusion
 CEA remains the standard of care for patients with
severe carotid disease in the absence of concomitant
medical or anatomical conditions known to increase
the risk of surgery.
 High-risk patients may be potential candidates for
stenting, as suggested with the SAPPHIRE trial.
 CAS is a reasonable option when performed by
operators with established peri-procedural morbidity
and mortality rates of 4% to 6%
 There is no role for stenting in asymptomatic patients
at this time