Inclusion Criteria

• ≥ 18 years of age.
• ability to cooperate with study procedures and agrees to return for all required follow-up visits, tests and exams
• Female subjects of childbearing potential must have a documented negative pregnancy test within 30 days prior to the index procedure.
• Subjects taking warfarin may be included if their dosage is reduced before the index procedure to result in an INR of 1.5 or less. Warfarin may be restarted to therapeutic dose after the index procedure.
• signed written informed consent prior to the initiation of any study procedures, using a form that is approved by the IRBoard or Ethics Committee
• life expectancy is at least two years
• lesion located in the internal carotid artery; the carotid bifurcation may be involved.
• target lesion is intended to be treated with a single stent
• Target ICA vessel diameter must be visually estimated to be:
• ≥ 2.5 mm & ≤ 7.0 for the Emboshield Pro,≥ 2.8 mm & ≤ 6.2 for the Emboshield (Gen 3) & ≥ 4.0 mm & ≤ 9.0 mm for the Xact stent treatment area.
• The subject has a carotid artery stenosis determined by ultrasound or angiography (visual estimate) to be: ≥ 50% for symptomatic subjects OR ≥ 80% for asymptomatic subjects
• High-risk inclusion criteria for either anatomical or co-morbid risk factors are present. The subject must fulfill at least one of the criteria in either category listed below.

Category I - Anatomic Risk Factors

• Previous radiation treatment to the neck or radical neck dissection
• Target lesion is at or above the second vertebral body C2 (level of jaw)
• Inability to extend the head due to cervical arthritis or other cervical disorders
• Tracheostomy or tracheal stoma
• Laryngectomy
• Contralateral laryngeal nerve palsy
• Severe tandem lesions

Category II - Co-morbid Risk Factors

• Previous CEA with significant restenosis (as defined for symptomatic or asymptomatic subjects)
• Total occlusion of the contralateral carotid artery Left ventricular ejection fraction < 35%
• Congestive Heart failure New York Heart Association (NYHA) Functional Class III or higher
• Dialysis dependent renal failure
• Canadian Cardiovascular Society Angina Classification III or higher or unstable angina
• Requires coronary artery bypass surgery, cardiac valve surgery, peripheral vascular surgery, or abdominal aortic aneurysm repair within 60 days
• ≥80 years of age
• MI within previous 6 wks
• Abnormal stress test. Treadmill, thallium or dobutamine echo are acceptable. The stress tests should be sufficiently abnormal to place the subject at increase risk for CEA

• Severe pulmonary disease, including at least one of the following: requires chronic O2 therapy; resting PO2 ≤ 60 mm Hg, Hematocrit ≥ 50%, FEV1 or DLCO

  • 50% of normal

Exclusion Criteria

• subject is participating in another investigational trial that would interfere with the conduct or result of this study
• dementia or a neurological illness that may confound the neurological evaluation
• Total occlusion of the target vessel
• existing, previously placed stent in the target artery
• known life-threatening allergy to the contrast media that cannot be treated.
• history of intolerance or allergic reaction to any of the study medications including aspirin, Clopidogrel bisulfate or Ticlopidine, heparin or Bivalirudin. Subjects must be able to tolerate a combination of aspirin and Clopidogrel or aspirin and Ticlopidine.
• GI bleed that would interfere with antiplatelet therapy
• known cardiac sources of emboli
• Hemoglobin < 8 gm/dL (unless on dialysis), platelet count < 50,000/mm3, or known heparin associated thrombocytopenia
• history of bleeding diathesis or coagulopathy including thrombocytopenia or an inability to receive heparin or Bivalirudin in amounts sufficient to maintain an ACT of >250, or will refuse blood transfusion
• atherosclerotic disease involving adjoining vessels that precludes safe placement of the guiding catheter or sheath
• abnormal angiographic findings that indicate the subject is at risk for a stroke due to a problem other than that of the target lesion
• evidence of a carotid artery dissection prior to the initiation of the index procedure
• angiographically visible thrombus
• any condition that precludes proper angiographic assessment or makes percutaneous arterial access unsafe
• Occlusion (TIMI 0 flow), or string sign of the ipsilateral common or internal carotid artery
• evidence of bilateral carotid stenosis that would require intervention within 30 days of the index procedure
• evidence of a stroke within the previous 30 days of the index procedure
• planned treatment of a non-target lesion within 30 days post index procedure
• history of intracranial hemorrhage within the previous 3 months, including hemorrhagic transformation of an ischemic stroke
• history of an ipsilateral stroke with fluctuating neurologic symptoms within 1 yr of the index procedure