Carotid stenosis caused by atherosclerosis is a significant risk factor for ischemic stroke, accounting for up to 15% of all strokes and transient ischemic attacks. Randomized clinical trials (RCTs) have demonstrated the benefits of carotid endarterectomy (CEA) in reducing stroke risk in patients with severe symptomatic carotid stenosis. Carotid artery stenting (CAS) has been developed as an alternative to CEA, offering several potential advantages, such as avoiding local surgical complications. However, unlike CEA, CAS has not been compared to medical therapy in RCTs for symptomatic carotid stenosis.

CEA vs CAS Comparison:

Early RCTs conducted in the 2000s showed that CAS was associated with a higher risk of procedural stroke or death compared to CEA (8.9% vs 5.8%; RR 1.53, 95% CI 1.20-1.96, p=0.0006). However, CAS was found to be as effective as CEA in preventing recurrent ipsilateral strokes up to 10 years after treatment. Interestingly, an ancillary study of the ICSS trial showed that significantly more patients in the CAS group (50%) than in the CEA group (17%) had new ischemic lesions on diffusion-weighted MRI (DWI), suggesting that DWI might serve as a surrogate outcome measure for future carotid intervention trials.

Data Analysis and Recent Advances:

Individual pooled data analysis of RCTs indicated that CAS could be as safe and effective as CEA in patients under 70 years old. Recent advances in CAS technology, stenting techniques, antiplatelet therapy, and pre-treatment imaging have improved the periprocedural safety of CAS. Due to its ability to treat patients soon after a stroke, CAS has become increasingly used in routine clinical practice.

Study Objectives:

The question remains whether CAS is as safe as CEA in patients with recent symptomatic severe carotid stenosis. The study's objectives are:

Primary Objective:

To assess whether carotid stenting is non-inferior to carotid endarterectomy in preventing new ischemic lesions on DWI MRI, confirmed by a core lab.

• To assess the difference between groups regarding post-intervention MRI characteristics in terms of ischemic lesion number and size, vessel occlusion and hemorrhagic transformation

• To assess differences between groups with regard to the procedural risks and efficacy (within 30 days after procedure) of

  1. any stroke or death
  2. any stroke,
  3. disabling or fatal stroke
  4. death
  5. transient ischemic attack
  6. myocardial infarction
  7. local complication
  8. cranial nerve palsy

Inclusion Criteria:

• Patient age 18 years or over
• Hemispheric or retinal transient ischemic attack or a non-disabling stroke (or retinal infarct) within 15 days before enrolment
• Stenosis of 50% to 99% in the symptomatic carotid artery (NASCET method) for whom revascularisation is decided according to guidelines

Exclusion Criteria:

• Patients unwilling or unable to participate in follow-up for whatever reason
• Preexisting disability (Modified Rankin Score ≥ 3)
• Nonatherosclerotic carotid disease
• Severe tandem lesions
• Previous revascularization of the symptomatic carotid stenosis
• History of bleeding disorder
• Unstable angina
• Contraindication to dual antiplatelet therapy
• Contraindication to MRI
• Life expectancy of less than 2 years
• Percutaneaous or surgical intervention within 30 days before or after the study procedure
• Stenotic lesion on arterial workup appeared as not a factor in the selection

Individual participant data (IPD) that underlie results in publication could be shared. IPD detailed in the protocol of a planned metaanalysis could be shared.

Two years after the last publication

Data sharing must be accepted by the sponsor and the PI. Technical feasibility and financial support will be discussed before mandatory contractualization. Processing of shared data must comply with GDPR.