Atrial fibrillation (AF) is the most common cardiac arrhythmia, affecting between 2.7 and 6.1 million people in the United States. The prevalence of AF increases with age and is often associated with structural heart disease and co-morbidities that are common in the Veteran population. AF is the most important cause of cardioembolic stroke, which accounts for 14-36% of all ischemic strokes. While patients at highest risk for AF-related stroke also often have other independent risk factors for stroke secondary to atherosclerotic aortic or carotid disease, most cardiac sources of embolism are thought to be due to thrombus formation from blood stasis in the left atrium. Among patients with non-valvular AF more than 90% of thrombi develop in the left atrial appendage (LAA). Antithrombotic therapy with aspirin, warfarin, or one of several newer oral anticoagulants reduces the risk of stroke due to both atrial fibrillation and atherosclerotic disease but is associated with a risk of serious bleeding. As a potential alternative to long-term anticoagulant therapy, various LAA exclusion procedures have been developed in an attempt to isolate the LAA from circulating blood flow. These procedures, including both surgical occlusion and removal of the LAA and percutaneous catheter-based interventions to occlude the LAA, may be beneficial in reducing risk of cardioembolic stroke originating from the LAA.

The purpose of this report is to systematically review the literature to better understand the balance of benefits and harms of surgical or percutaneous LAA exclusion procedures.

Contents

• PREFACE
• EXECUTIVE SUMMARY
  • INTRODUCTION
  • METHODS
  • SUMMARY OF FINDINGS
• ABBREVIATIONS
• INTRODUCTION
• METHODS
  • TOPIC DEVELOPMENT
  • SEARCH STRATEGY
  • STUDY SELECTION
  • DATA ABSTRACTION
  • QUALITY ASSESSMENT
  • DATA SYNTHESIS
  • RATING THE BODY OF EVIDENCE
  • PEER REVIEW
• RESULTS
  • LITERATURE FLOW
  • PERCUTANEOUS LAA INTERVENTIONS
  • SURGICAL LAA INTERVENTIONS
• SUMMARY AND DISCUSSION
  • Percutaneous LAA exclusion
  • Surgical LAA exclusion
  • LIMITATIONS
  • RESEARCH GAPS/FUTURE RESEARCH
  • CONCLUSIONS
• REFERENCES
• APPENDIX A SEARCH STRATEGIES
• APPENDIX B STUDY SELECTION
• APPENDIX C QUALITY ASSESSMENT
• APPENDIX D LAA DEVICE MANUFACTURERS
• APPENDIX E PEER REVIEWER COMMENTS AND AUTHOR RESPONSES

Prepared for: Department of Veterans Affairs, Veterans Health Administration, Quality Enhancement Research Initiative, Health Services Research & Development Service, Washington, DC 20420. Prepared by: Evidence-based Synthesis Program (ESP), Portland VA Medical Center, Portland, OR, Devan Kansagara, MD, Director

Suggested citation:

Noelck N, Papak J, Freeman M, Paynter R, Low A, Motu'apuaka M, Kondo K, Kansagara D. The Effectiveness of Procedures to Remove or Occlude the Left Atrial Appendage: A Systematic Review of the Evidence. VA ESP Project #05-225; 2015.

This report is based on research conducted by the Evidence-based Synthesis Program (ESP) Center located at the Portland VA Health Care System, Portland, OR, funded by the Department of Veterans Affairs, Veterans Health Administration, Office of Research and Development, Quality Enhancement Research Initiative. The findings and conclusions in this document are those of the author(s) who are responsible for its contents; the findings and conclusions do not necessarily represent the views of the Department of Veterans Affairs or the United States government. Therefore, no statement in this article should be construed as an official position of the Department of Veterans Affairs. No investigators have any affiliations or financial involvement (eg, employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties) that conflict with material presented in the report.