To compare the 30-day safety and efficacy of the GORE Flow Reversal System when used with approved carotid stents to an Objective Performance Criterion derived from distal embolic protection studies.

The GORE Flow Reversal System, manufactured by W. L. Gore & Associates, Inc., was developed as a proximal occlusion device to reverse the flow of blood in the carotid artery. It is designed to achieve embolic protection prior to crossing the lesion in the majority of cases in order to minimize the possibility of an adverse event occurrence.

The objective of this study is to assess the safety and effectiveness of the GORE Flow Reversal System when used to provide embolic protection during Carotid Artery Stent (CAS) procedures. Subjects diagnosed with carotid stenosis requiring revascularization and are at high risk for adverse events from CEA are eligible to participate.

Inclusion Criteria:

• Carotid stenosis requiring revascularization and indicating either symptomatic status, with carotid stenosis ≥ 50% OR asymptomatic status with carotid stenosis ≥ 80%
• Target lesion is located in one of the following:(a) internal carotid artery (ICA) (b) bifurcation (c) common carotid artery (CCA) proximal to the bifurcation
• At Anatomic risk for adverse events from CEA (e.g. restenosis after a prior CEA) OR at Co-morbid risk for adverse events from CEA (e.g., unstable angina with ECG changes)

Exclusion Criteria:

• Recent surgical procedure within 30 days before or after the stent procedure
• Uncontrolled sensitivity to contrast media
• Renal Insufficiency
• Recent evolving, acute stroke within 21 days of study evaluation
• Myocardial infarction within 72 hours prior to stent procedure
• History of a prior major ipsilateral stroke with residual neurological deficits likely to confound the neurological assessments (e.g., NIHSS)
• Neurological deficits not due to stroke likely to confound the neurological assessments (e.g., NIHSS)

Angiographic Exclusion Criteria:

• Isolated ipsilateral hemisphere leading to subject intolerance to reverse flow
• Total occlusion of the ipsilateral carotid artery
• Pre-existing stent in the ipsilateral carotid artery OR the contralateral carotid artery that extends into the aortic arch
• Presence of a filling defect, thrombus, occlusion or "string sign" in the target vessel
• Severe lesion calcification restricting stent deployment
• Carotid stenosis located distal to target stenosis that is more severe than target stenosis
• > 50% stenosis of the CCA proximal to target vessel
• Known mobile plaque in the aortic arch

30 days postprocedure (0-40 days given 10-day late follow-up window)

AEs reported by investigative sites via Adverse Event Case Report Form (CRF), using study-specific coding. Site-reported adverse events that were potential Major Adverse Events (stroke or TIA) were adjudicated by the independent Clinical Events Committee.