IMMEDIATE AND LATE CLINICAL OUTCOMES OF CAROTID ARTERY STENTING IN PATIENTS WITH SYMPTOMATIC AND ASYMPTOMATIC CAROTID ARTERY STENOSIS A 5 year Prospective Analysis

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IMMEDIATE AND LATE CLINICAL OUTCOMES OF CAROTID
ARTERY STENTING IN PATIENTS WITH SYMPTOMATIC AND
ASYMPTOMATIC CAROTID ARTERY STENOSISA 5 year
Prospective Analysis

• Gary S. Roubin, Gishel New, Sririam S. Iyer, Jiri
  J. Vitek, Nadim Al-Mubarak, Ming W. Liu, Jay
  Yadav, Camilo Gomez, Richard E. Kuntz
• Circulation 103(4)532-537, 2001 Jan 30

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AIMS

• Determine short and long term outcomes of carotid
  stenting in a large prospective cohort of patients

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METHODS(1) - PATIENT POPULATION

• 528 pts between 8/9/94 - 8/9/99
• 74 bilateral ( 604 hemispheres / arteries)
• Same three proceduralists
• Patients either symptomatic with gt50 stenosis,
  or asymptomatic with gt60 stenosis
• Included symptomatic patients ineligible for
  NASCET ( gt79yo, Prior CEA, AF etc)
• Included patients with disease of CCA and
  Fx-ECA(n2) lesions (not normally treated by CEA)

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METHODS(2) - PATIENT POPULATION

• Exclusions
• - Major neurological deficit
• - Illness impeding informed consent
• - Severe renal insufficiency
• - PVD preventing femoral a. access
• - Severe diffuse ATS of CCA
• - Chronic total occlusions
• - Long pre-occlusive lesions

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METHODS(3) - PREPROCEDURE PROTOCOL

• CT or MRI brain for baseline
• Aspirin 325mg BD Ticlopidine 250mg BD or
  Clopidogrel 150mg BD for 48hrs
• NIH Stroke Scale by certified neurologist before
  and within 24 hrs post-op

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METHODS(4) - TECHNIQUE

• No sedation
• Neurological assessment throughout procedure
• Hyper- and hypo-tension and bradycardia managed
• Cervical-cerebral angiography and intracranial
  viewsto assess C-of-W before and after stenting
• stenosis as per NASCET criteria
• Assessed by neurologist within 24 hrs and then
  discharged.
• Aspirin 325mg BD for life ticlopidine or
  clopidogrel for 4 weeks

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METHODS(5) - DATA COLLECTION / FOLLOW UP

• 518 of the 520 who survived gt30 days followed up
• Mean follow up 17 /- 12 months
• Phone I/views at 1 month then every 6 months
• Patients to notify if symptoms of neuro event
• Neurological event occurring ----gt rpt CT Head
  and neurologist assessment

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METHODS(5) - DATA COLLECTION / FOLLOW UP

• DEFINITIONS
• (A) TIA - focal retinal or hemispheric event from
  which pt recovers within 24 hrs
• (B) Minor Non-fatal Stroke - new neurological
  deficit resolving completely within 30 hrs or
  increases NIH Stroke Scale by lt 3
• (C) Major Non- fatal Stroke - new neurological
  deficit persisting gt30 days, increases NIH Stroke
  Scale by gt4

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RESULTS (1)- PATIENT CHARACTERISTICS
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RESULTS (2)- ANGIOGRAPHIC/ STENT RESULTS

• 270 pts had bilateral carotid artery disease
• 61 arteries (10) had occluded contralateral ICA
• 76 pts (15) had bilateral carotid artery
  stenting (30 in same procedure)
• Mean stenosis pre-stenting 74 /- 14
• Mean stenosis post-stenting 5 /- 9
• Stents used per vessel 1.2 /- 0.6
• 424 (70) stents self expandable rest balloon
  expandable
• 12 technically unsuccessful procedures (2)

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RESULTS (3)- 30 DAY OUTCOMES

• Symptomatic and asymptomatic pts had similar 30
  day complication rates ( 8.2 vs 6.3 P0.47)
• Male and female pts had similar 30 day cx rates
  (8.0 vs 5.9 p0.4)

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RESULTS (3)- 30 DAY OUTCOMES

• Patients gt80yo had higher rates major non-fatal
  stroke than lt80 yo

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RESULTS (3)- 30 DAY OUTCOMES
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RESULTS (4)- LATE FOLLOW UP

• 16 pts (3) required rpt angioplasty for
  restenosis
• 2 pts (0.3) required CEA ( 1 for failed attempt
  stenting, 1 for restenosis)
• 75 late non-neurological deaths (cardiac, ca)
• 2 late deaths indeterminate cause

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RESULTS (4)- LATE FOLLOW UP

• 3 year freedom from all all fatal and non-fatal
  strokes 88 /- 2 (A)
• For those surviving 30 days, 3 year freedom from
  all fatal and non-fatal strokes 95 /- 2 (B)

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RESULTS (4)- LATE FOLLOW UP

• A 3 year freedom from all fatal and non fatal
  strokes in lt80yo 90 /-2 versus gt80yo 73 /-
  4 (Plt0.0001)
• BExcluding 30 day post procedure period, 3 year
  freedom from all fatal and non fatal strokes in
  lt80yo 95 /- 2 versus gt80yo 91 /- 1
  (Plt0.01)
• Sex, presence /absence symptoms did not correlate
  with long term freedom from stroke

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AUTHORS DISCUSSION

• Similar periprocedural complication rates when
  compare results of this study to studies
  involving CEA in symptomatic (NASCET) and
  asymptomatic patients (ACAS)
• Favourable long term results in this trial
  compared to NASCET and ACAS patients
• Agegt80 a predictor for periprocedural and late
  complications
• CS has no neck wound or CN complications much
  lower risk of AMI

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LIMITATIONS OF THE STUDY (1)

• No randomisation. No control group.
• No blinding .
• - Patient, assessing neurologist and phone
  interviewers all knew patient had carotid
  stenting and hence reports of symptoms or short
  /long term effects could be biased

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LIMITATIONS OF THE STUDY (2)

• Selection bias
• (a) Included pts not normally treated by CEA
  (isolated CCA and Fx-ECA disease n36). May have
  better outcomes due to technical ease or less
  likely CVA
• Including these pts who arent in CEA group
  makes the groups inherently different and hence
  direct comparisons to results of these trials not
  valid

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LIMITATIONS OF THE STUDY (3)

• (b) Excluded patients with severe diffuse ATS of
  CCA, chronic total occlusions, and long
  preocclusive lesions. These patients included in
  NASCET and ACAS trials. Probably biases towards
  better results comparably for stent group as
  people with worse lesions selected out. To
  compare to NASCET/ACAS trials would have to
  exclude these patients with more difficult
  lesions from these trials.
• Not told how many patients excluded on these
  criteria.

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LIMITATIONS OF THE STUDY (4)

• ( c ) Included patients not eligible for NASCET -
  hence creates inherent differences in populations
  making direct comparison of results invalid.

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CONCLUSIONS

• Acceptable 30 day and late complication rates (
  but still no real proof that results better or
  comparable to CEA)
• Need large randomised controlled trial to answer
  the question of how this procedure really
  compares to CEA