Effects of Cerebral Protection With Filters vs. Flow Reversal on Cerebral Embolization After Carotid Artery Stenting

• Any Stroke, TIA, MI or death [ Time Frame: Within 30 days after carotid artery stenting ] [ Designated as safety issue: Yes ]
  Occurrence of any stroke, transient ischemic attack (TIA), myocardial infarction, or death within 30 days after carotid artery stenting.
• Technical success of carotid artery stenting [ Time Frame: 4 weeks. ] [ Designated as safety issue: No ]
• Stent thrombosis [ Time Frame: within 30 days post procedure ] [ Designated as safety issue: Yes ]
  Thrombosis of carotid artery stent implanted during the index procedure, assessed within 30 days after procedure

• Any Stroke, TIA, MI or death [ Time Frame: Within 30 days after carotid artery stenting ] [ Designated as safety issue: Yes ]
  Occurrence of any stroke, transient ischemic attack (TIA), myocardial infarction, or death within 30 days after carotid artery stenting.
• Technical success of carotid artery stenting [ Time Frame: Within 24 hours post procedure ] [ Designated as safety issue: No ]
• Stent thrombosis [ Time Frame: within 30 days post procedure ] [ Designated as safety issue: Yes ]
  Thrombosis of carotid artery stent implanted during the index procedure, assessed within 30 days after procedure

Carotid artery stenting (CAS) with cerebral embolic protection is the preferred treatment for narrowing of the carotid arteries in patients at high risk for open surgery. Special devices are used to protect the brain from particles(emboli) that may break off when the narrowing or blockage is cleared during the angioplasty and stenting procedure. Although filters are most frequently used, protection systems consisting of balloons and flow reversal are also available for cerebral embolic protection. However, there is little information about the effectiveness of filters compared with balloons and flow reversal for prevention of embolization during CAS. The aim of our study is to address this major problem. Our study was designed to answer two specific questions: First, the study will investigate whether balloon-based protection systems are more effective than filters in reducing the amount of particles that break off and travel to the brain during CAS. For this purpose two imaging techniques will be used: magnetic resonance imaging of the brain (MRI), and transcranial doppler (detection of microparticles in the small brain vessels using ultrasound). Second, it will be investigated whether the use of balloon-based protection devices are more effective than filters for prevention of stroke, heart attacks, and death after carotid stenting. The results of the study will provide important information to find out the best way to protect the brain from plaque fragments that may break off during CAS.

• Carotid Artery Disease
• Stroke

• Active Comparator: Carotid filter
  Patients randomized to this arm of the study will receive FDA-approved filter devices for cerebral embolic protection during carotid artery stenting
  Intervention: Procedure: Type of embolic protection method
• Active Comparator: Carotid reversal of flow
  Patients randomized to this arm of the study will receive reversal of flow with the FDA-approved Gore Neuroprotection System for cerebral protection during carotid artery stenting.
  Intervention: Procedure: Type of embolic protection method

Inclusion Criteria:

1. Patient is at least 18 years old;
2. Patient is willing and capable of complying with the study protocol requirements, including the specified follow-up period;
3. Patient is willing to provide written informed consent prior to enrollment in the study;
4. Male, infertile female, or non-lactating female of child bearing potential practicing an acceptable method of birth control with a negative pregnancy test within 7-days prior to study procedure;
5. Patient is either symptomatic, i.e. with a history of TIAs or non-disabling stroke within 6 months of the procedure, with carotid stenosis ≥ 50%, or asymptomatic with carotid stenosis ≥ 80%, as diagnosed by angiography using NASCET methodology;4
6. The target lesion is located in the internal carotid artery (ICA) and the reference vessel diameter, i.e. the common carotid artery (CCA) is < 10 mm based on angiographic assessment.

Exclusion Criteria:

1. Acute evolving or recent stroke within 7 days of study evaluation;
2. Cardiac embolism;
3. Acute myocardial infarction less than 72 hours prior to the procedure;
4. Major surgical procedure within 30 days preceding CAS;
5. Major surgical procedure within 30 days after the index procedure;
6. Prior major ipsilateral stroke with residual deficit or other neurologic conditions that may affect neurological assessments;
7. Pregnancy or breastfeeding;
8. Severe chronic renal insufficiency (serum creatinine is ≥ 2.5 mg/dL);
9. Contraindication to study medications, including antiplatelet therapy;
10. Prior sensitivity to contrast media that cannot adequately be controlled with pre-medication;
11. Untreatable bleeding diathesis or hypercoagulable state or refusal to blood transfusions;
12. History of uncontrolled pulmonary hypertension;
13. Intracranial pathology;
14. Patient unable or unwilling to undergo DW-MRI of the brain
15. Patient without adequate transtemporal window for transcranial Doppler examination
16. Other anatomic or co-morbid conditions that, in the investigator's opinion, could limit the patient's ability to participate in the study or to comply with follow-up requirements, or impact the scientific soundness of the study results.
17. Isolated ipsilateral hemisphere leading to subject intolerance to flow reversal;
18. Anatomic conditions that preclude performance of carotid artery stenting.