CAROTID STENOSIS















  • Data is from studies where patients were taking daily aspirin
  • Reference [1]
Symptomatic carotid stenosis
Degree of stenosis Annual stroke rate
≥ 70% 13%
50 - 69% 4.4%
≤ 50% 3.74%
Asymptomatic carotid stenosis
Degree of stenosis Annual stroke rate
≥ 60% 2 - 3%

















  • Primary outcome - composite of same-sided stroke as carotid stenosis, any operative stroke, or any operative death
  • Nonsignificant = statistically nonsignificant
  • Reference [4]
Degree of stenosis Absolute risk reduction in the primary outcome after 5 years
(CEA minus medical therapy)
90 - 99% 32.4%
80 - 89% 17.7%
70 - 79% 15.8%
60 - 69% 5.9% (nonsignificant)
50 - 59% 4% (nonsignificant)
30 - 49% 3.2% (nonsignificant)
< 30% -2.2% (worse outcome for CEA)
(nonsignificant)
Near-occlusion
(defined as 95% stenosis)
-1.7% (worse outcome for CEA)
(nonsignificant)
See occlusion below





ACT I trial - CAS vs CEA for Asymptomatic Carotid Stenosis, NEJM (2016) [PubMed abstract]
  • The ACT I trial enrolled 1453 patients with asymptomatic carotid stenosis
Main inclusion criteria
  • Age ≤ 79 years
  • Asymptomatic carotid stenosis defined as having been free, in the ipsilateral hemisphere, from stroke, TIA, and amaurosis fugax for 180 days before enrollment
  • Stenosis of 70 - 99% in the absence of substantial (> 60%) contralateral stenosis
Main exclusion criteria
  • High risk for operative complications
  • Intracranial hemorrhage or hemorrhagic stroke within 1 year
Baseline characteristics
  • Average age 68 years
  • History of stroke ∼ 5.7%
  • History of TIA - 7%
  • Average % stenosis - 74%
  • Average lesion length - 18.5 mm
  • History of CAD - 52%
Randomized treatment groups
  • Group 1 (1089 patients) - CAS
  • Group 2 (364 patients) - CEA
  • All patients received aspirin 325 mg once daily starting 3 days before the procedure and continued indefinitely
  • Patients who had CAS received clopidogrel 75 mg once daily starting 3 days before the procedure and for 30 days thereafter
Primary outcome: Composite of death, stroke (ipsilateral or contralateral, major or minor) or myocardial infarction during the 30 days after the procedure or ipsilateral stroke during the 365 days after the procedure
Results

Duration: 365 days
Outcome CAS CEA Comparisons
Primary outcome 3.8% 3.4% p=0.69
Periprocedural stroke (within 30 days) 2.8% 1.4% p=0.23
Periprocedural heart attack (within 30 days) 0.5% 0.9% p=0.41
Overall mortality (estimated 5-year) 12.9% 10.6% p=0.21
Any stroke (estimated 5-year) 6.9% 5.3% p=0.44
  • 16 patients in the CAS group ended up having CEA, and 1 patient in the CEA group ended up having CAS (crossovers)
  • 31 patients in the CAS group and 20 patients in the CEA group did not undergo either procedure

Findings: In this trial involving asymptomatic patients with severe carotid stenosis who were not at high risk for surgical complications, stenting was noninferior to endarterectomy with regard to the rate of the primary composite end point at 1 year. In analyses that included up to 5 years of follow-up, there were no significant differences between the study groups in the rates of non-procedure-related stroke, all stroke, and survival.


ICSS trial - CAS vs CEA for Symptomatic Carotid Stenosis, Lancet (2015) [PubMed abstract]
  • The ICSS trial enrolled 1713 patients with symptomatic carotid stenosis
Main inclusion criteria
  • Symptomatic carotid artery stenosis with ≥ 50% stenosis of the carotid artery
  • Eligible for CEA and CAS
Main exclusion criteria
  • History of major stroke
Baseline characteristics
  • Average age 70 years
  • ≥ 70% stenosis - 90% of subjects
  • Most recent event: Ipsilateral ischemic stroke - 45% | Ipsilateral TIA - 33% | Amaurosis fugax - 17%
Randomized treatment groups
  • Group 1 (855 patients) - CAS
  • Group 2 (858 patients) - CEA
Primary outcome: Fatal or disabling stroke in any territory after randomisation to the end of follow-up
Results

Duration: Median of 4.2 years
Outcome CAS CEA Comparisons
Primary outcome 6.4% 6.5% HR 1.06, 95%CI [0.72 – 1.57], p=0.77
Any stroke 15.2% 9.4% HR 1.71, 95%CI [1.28 – 2.30], p<0.001
Overall mortality 17.4% 17.2% HR 1.17, 95%CI [0.92 – 1.48], p=0.19

Findings: Long-term functional outcome and risk of fatal or disabling stroke are similar for stenting and endarterectomy for symptomatic carotid stenosis
CREST trial - CAS vs CEA for Symptomatic and Asymptomatic Carotid Stenosis, NEJM (2010) [PubMed abstract]
  • The CREST trial enrolled 2522 patients with symptomatic or asymptomatic carotid stenosis
Main inclusion criteria
  • Symptomatic patients - stroke or TIA within 180 days of study entry, stenosis ≥ 70% (ultrasound, CTA, MRA) or ≥ 50% on angiography
  • Asymptomatic patients - carotid stenosis ≥ 60% on angiography, ≥ 70% on ultrasound, ≥ 80% on CTA or MRA
Main exclusion criteria
  • Previous severe stroke
  • A fib
  • MI within 30 days
Baseline characteristics
  • Average age 69 years
  • Asymptomatic carotid stenosis - 47%
  • Severe stenosis (≥ 70%) - 86%
Randomized treatment groups
  • Group 1 (1262 patients) - CAS
  • Group 2 (1240 patients) - CEA
Primary outcome: Composite of stroke, heart attack, periprocedural all-cause mortality, and same-sided stroke within 4 years of randomization (estimated with Kaplan-Meier curve)
Results

Duration: Median of 2.5 years
Outcome CAS CEA Comparisons
Primary outcome 7.2% 6.8% HR 1.11, 95%CI [0.81 - 1.51], p=0.51
Periprocedural stroke (within 30 days) 4.1% 2.3% HR 1.79, 95%CI [1.14 - 2.82], p=0.01
Periprocedural heart attack (within 30 days) 1.1% 2.3% HR 0.50, 95%CI [0.26 - 0.94], p=0.03
Overall mortality 11.3% 12.6% HR 1.12, 95%CI [0.83 - 1.51], p=0.45
  • 5.7% of patients in the CAS group ended up having CEA, and 1% of patients in the CEA group ended up having CAS (crossovers)
  • Patients aged < 70 years tended to have better outcomes with CAS, and patients > 70 years tended to have better outcomes with CEA

Findings: Among patients with symptomatic or asymptomatic carotid stenosis, the risk of the composite primary outcome of stroke, myocardial infarction, or death did not differ significantly in the group undergoing carotid-artery stenting and the group undergoing carotid endarterectomy. During the periprocedural period, there was a higher risk of stroke with stenting and a higher risk of myocardial infarction with endarterectomy.
CREST trial 10-year follow-up, NEJM (2016) [PubMed abstract]
  • A follow-up to the CREST trial was published in 2016. It tracked 2502 patients from the original trial for up to 10 years.

Duration: Median 7.4 years
Outcome (10-year estimated) CAS CEA Comparisons
Primary outcome 11.8% 9.9% HR 1.10, 95%CI [0.83 - 1.44], p=0.51
Stroke or periprocedural death 11% 7.9% HR 1.37, 95%CI [1.01 - 1.86], p=0.04
Any stroke 10.8% 7.9% HR 1.33, 95%CI [0.98 - 1.80], p=0.07
Postprocedural ipsilateral stroke 6.9% 5.6% HR 0.99, 95%CI [0.64 - 1.52]
  • There was no significant difference in treatment effect between symptomatic and asymptomatic patients [8]

Findings: Over 10 years of follow-up, we did not find a significant difference between patients who underwent stenting and those who underwent endarterectomy with respect to the risk of periprocedural stroke, myocardial infarction, or death and subsequent ipsilateral stroke. The rate of postprocedural ipsilateral stroke also did not differ between groups.