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

The recruitment status of this study is unknown. The completion date has passed and the status has not been verified in more than two years.
Verified February 2015 by Dallas VA Medical Center.
Recruitment status was:  Recruiting
American Heart Association
Information provided by (Responsible Party):
Carlos H. Timaran, Dallas VA Medical Center Identifier:
First received: August 5, 2011
Last updated: February 9, 2015
Last verified: February 2015
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.

Condition Intervention
Carotid Artery Disease
Procedure: Carotid filter
Procedure: Carotid reversal of flow

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single Blind (Outcomes Assessor)
Primary Purpose: Treatment
Official Title: Effects of Cerebral Protection With Filters vs. Flow Reversal on Cerebral Embolization After Carotid Artery Stenting

Further study details as provided by Dallas VA Medical Center:

Primary Outcome Measures:
  • Cerebral embolization [ Time Frame: Within 24 hours post carotid artery stenting ]
    Number of cerebral macro and microembolic events assessed as the number of new ipsilateral brain lesions detected by brain diffusion-weighted magnetic resonance imaging within 24 hours post carotid artery stenting and number of intraoperative microembolic signals detected by transcranial Doppler in the middle cerebral artery ipsilateral to the procedure during carotid artery stenting.

Secondary Outcome Measures:
  • Any Stroke, TIA, MI or death [ Time Frame: Within 30 days after carotid artery stenting ]
    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. ]
  • Stent thrombosis [ Time Frame: within 30 days post procedure ]
    Thrombosis of carotid artery stent implanted during the index procedure, assessed within 30 days after procedure

Estimated Enrollment: 50
Study Start Date: October 2011
Estimated Study Completion Date: June 2015
Estimated Primary Completion Date: April 2015 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Active Comparator: Carotid filter
For this intervention group, patients will receive FDA-approved filter devices for cerebral embolic protection during carotid artery stenting intervention.
Procedure: Carotid filter

Patients randomized to this group will receive filter devices to prevent cerebral embolization during carotid stenting, assessed by intraoperative transcranial Doppler and postoperative cerebral DW-MRI.

The filter used for this trial is the RX accunet embolic protection system manufactured by abbott.

Active Comparator: Carotid reversal of flow
For this intervention group, patients will receive reversal of flow with the FDA-approved Gore Neuroprotection System for cerebral protection during carotid artery stenting.
Procedure: Carotid reversal of flow
On the flow reversal arm two type of devices will be used. The first is the Gore flow reversal system, manufactured by LW Gore and the second device is the IVANTEC MoMa Ultra Embolic protection device, manufatured by IVANTEC.

  Show Detailed Description


Ages Eligible for Study:   18 Years and older   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

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.
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its identifier: NCT01414387

Contact: Carlos H Timaran, MD 214-857-1808

United States, Texas
Dallas VA Medical Center Recruiting
Dallas, Texas, United States, 75216
Contact: Carlos Timaran, MD    214-857-0336   
Sponsors and Collaborators
Dallas VA Medical Center
American Heart Association
Principal Investigator: Carlos H Timaran, MD Dallas VA Medical Center
  More Information

Responsible Party: Carlos H. Timaran, MD, Dallas VA Medical Center Identifier: NCT01414387     History of Changes
Other Study ID Numbers: 11GRNT7960035
Study First Received: August 5, 2011
Last Updated: February 9, 2015

Keywords provided by Dallas VA Medical Center:
carotid stenosis
cerebral embolization

Additional relevant MeSH terms:
Carotid Artery Diseases
Cerebrovascular Disorders
Brain Diseases
Central Nervous System Diseases
Nervous System Diseases
Vascular Diseases
Cardiovascular Diseases processed this record on April 28, 2017