Excerpt

Acute ischemic strokes are associated with poor outcomes and high healthcare burden. In patients with occlusions of large cerebral vessels, patients with high baseline stroke severity scores as defined by the National Institute of Health Stroke Score (NIHSS), and patients unlikely to benefit or having failed treatment with intravenous (IV) recombinant tissue plasminogen activator (rtPA), there is a need for alternative methods of revascularization which can improve outcomes without increasing the risk for intracranial hemorrhage. The uses of various neurothrombectomy devices (clot retrievers, aspiration/suction devices, snare-like devices, ultrasonography technologies, and lasers) have been examined in these populations. Currently, two neurothrombectomy devices are FDA-cleared through the FDA 510(k) process: the MERCI clot retriever and the Penumbra System. Various ongoing clinical trials are currently evaluating the impact of these devices, as well as other (off-label) neurothrombectomy devices, for the treatment of acute ischemic stroke. The goal of this technical brief is to describe neurothrombectomy devices currently being used or actively investigated in the treatment of patients with acute ischemic stroke and to summarize the evidence supporting their use.

Contents

• Preface
• Executive Summary
  • Background
  • Methods
  • Results
  • Discussion
  • Summary
• Background and Objectives for the Systematic Review
  • Prevalence of Ischemic Stroke
  • Natural History of Ischemic Stroke
  • Reperfusion Strategies for Treatment of Ischemic Stroke
  • Advances in Recanalization Using Neurothrombectomy Devices
  • Statement of Work
  • The Key Questions
  • Analytic Framework
• Methods
  • Key Terminology and Definitions
  • Criteria for Inclusion/Exclusion of Studies in the Review
  • Searching for the Evidence: Literature Search Strategies for Identification of Relevant Studies To Answer the Key Questions
  • Data Abstraction and Data Management
  • Assessment of Methodological Quality of Individual Studies
  • Data Synthesis
  • Grading the Evidence for Each Key Question
  • Future Research/Research Gaps
• Results
  • Key Question 1 What are the different types of neurothrombectomy devices in use or in development for treatment of acute ischemic stroke?
  • Key Question 2 From a systematic scan of studies of different types of neurothrombectomy devices, what are the type(s) of devices, study designs and sizes, patient characteristics, comparators used in comparative studies, lengths of follow-up, concurrent or prior therapies, outcomes measured, and adverse events, harms, and safety issues reported?
  • Key Question 3 What are the variables associated with use of the devices that may impact outcomes (e.g. time to deployment, training/expertise of interventionalist, location of infarct, concurrent therapies)?
• Discussion
  • Future Research/Research Gaps
• Summary
• References
• Appendixes
  • Appendix A MEDLINE and CENTRAL Search Strategies
  • Appendix B Citations for Included and Excluded Reports
  • Appendix C Tables of Included Study Characteristics, Inclusion and Exclusion Criteria
  • Appendix D Summary Figures and Tables

Acknowledgments: The University of Connecticut/Hartford Hospital Evidence-based Practice Center thanks Robert Quercia, M.S., Medical Editor; Jeffrey Mather, M.S., Statistician, Database Design; and Sharon Giovenale, M.S., Medical Librarian, for their invaluable help in completing this Technical Brief.

Technical Expert Panel: Colin P Derdeyn, MD, Vice-Chair, AHA Stroke Council’s Scientific Statements Oversight Committee, Professor of Radiology, Neurology and Neurological Surgery, Director, Center for Stroke and Cerebrovascular Disease, Washington University School of Medicine; Anthony J Furlan, MD, Gilbert Humphrey Professor, Chairman Department of Neurology, Neurological Institutes, University Hospitals Case Medical Center, Case Western Reserve University School of Medicine, Cleveland, OH; Patrick D Lyden, MD, FAAN, Chairman, Department of Neurology, Carmen & Louis Warschaw Chair in Neurology, Cedars-Sinai Medical Center, Los Angeles, CA; Wade S Smith, MD, PhD, Daryl R Gress Endowed Professor of Neurocritical Care and Stroke, Director, UCSF Neurovascular Intensive Care Unit, Department of Neurology, University of California, San Francisco School of Medicine.

Prepared for: Agency for Healthcare Research and Quality, U.S. Department of Health and Human Services, Contract No. 290-2007-10067-I. Prepared by: University of Connecticut/Hartford Hospital Evidence-based Practice Center (EPC)

Suggested citation:

Baker WL, Colby JA, Tongbram V, Talati RA, Silverman IE, White CM, Kluger JK, Coleman CI. Neurothrombectomy Devices for Treatment of Acute Ischemic Stroke. Technical Brief No. 4. (Prepared by the University of Connecticut/Hartford Hospital Evidence-based Practice Center under Contract No. 290-2007-10067-I.) AHRQ Publication No. 11-EHC020-EF. Rockville, MD; Agency for Healthcare Research and Quality. January 2011. Available at: http://www.effectivehealthcare.ahrq.gov/reports/final.cfm.

This report is based on research conducted by the University of Connecticut/Hartford Hospital Evidence-based Practice Center under contract to the Agency for Healthcare Research and Quality (AHRQ), Rockville, MD (Contract No. 290-2007-10067-I). The findings and conclusions in this document are those of the author(s), who are responsible for its content, and do not necessarily represent the views of AHRQ. No statement in this report should be construed as an official position of AHRQ or of the U.S. Department of Health and Human Services.

The information in this report is intended to help clinicians, employers, policymakers, and others make informed decisions about the provision of health care services. This report is intended as a reference and not as a substitute for clinical judgment.

This report may be used, in whole or in part, as the basis for the development of clinical practice guidelines and other quality enhancement tools, or as a basis for reimbursement and coverage policies. AHRQ or U.S. Department of Health and Human Services endorsement of such derivative products or actions may not be stated or implied.

None of the investigators have any affiliations or financial involvement that conflicts with the material presented in this report.

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