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

AIMS

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

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 >50% stenosis,

or asymptomatic with >60% stenosis

• Included symptomatic patients ineligible for NASCET ( >79yo, Prior CEA, AF etc)

• Included patients with disease of CCA and Fx-ECA(n=2) lesions (not normally treated by CEA)

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

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

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

METHODS(5) - DATA COLLECTION / FOLLOW UP

• 518 of the 520 who survived >30 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 ----> rpt CT Head and neurologist assessment

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 < = 3

(C) Major Non- fatal Stroke - new neurological deficit persisting >30 days, increases NIH Stroke Scale by >4

RESULTS (1)- PATIENT CHARACTERISTICS

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%)

RESULTS (3)- 30 DAY OUTCOMES

• Symptomatic and asymptomatic pts had similar 30 day complication rates ( 8.2% vs 6.3%; P=0.47)

• Male and female pts had similar 30 day cx rates (8.0% vs 5.9%; p=0.4)

RESULTS (3)- 30 DAY OUTCOMES

• Patients >80yo had higher rates major non-fatal stroke than <80 yo

RESULTS (3)- 30 DAY OUTCOMES

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

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)

RESULTS (4)- LATE FOLLOW UP

• A: 3 year freedom from all fatal and non fatal strokes in <80yo = 90 +/-2% versus >80yo = 73 +/- 4% (P<0.0001)

• B:Excluding 30 day post procedure period, 3 year freedom from all fatal and non fatal strokes in <80yo = 95 +/- 2% versus >80yo = 91 +/- 1 % (P<0.01)

• Sex, presence /absence symptoms did not correlate with long term freedom from stroke

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

• Age>80 a predictor for periprocedural and late complications

• CS has no neck wound or CN complications ; much lower risk of AMI

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

LIMITATIONS OF THE STUDY (2)

• Selection bias:

(a) Included pts not normally treated by CEA (isolated CCA and Fx-ECA disease; n=36). May have better outcomes due to technical ease or less likely CVA

Including these pts who aren’t in CEA group makes the groups inherently different and hence direct comparisons to results of these trials not valid

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.

LIMITATIONS OF THE STUDY (4)

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

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