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Nonpharmacologic therapy to prevent embolization in patients with atrial fibrillation

Authors
Ziyad M Hijazi, MD, MPH, FAAP, FACC, MSCAI, FAHA
Jacqueline Saw, MD, FRCPC, FACC
Section Editor
Bradley P Knight, MD, FACC
Deputy Editor
Gordon M Saperia, MD, FACC

INTRODUCTION

Most patients with atrial fibrillation should receive anticoagulant therapy to reduce the risk of systemic embolization. However, there are varying degrees of bleeding risk associated with anticoagulation and not all individuals are candidates for this therapy [1]. (See "Warfarin and other VKAs: Dosing and adverse effects" and "Risk of intracerebral bleeding in patients treated with anticoagulants".)

The optimal approach to reducing the risk of embolization in patients for whom long-term anticoagulation is indicated but who are unable to take it is not clear. Some nonpharmacologic strategies to prevent recurrent atrial fibrillation, such as radiofrequency catheter ablation, have not been proven to reduce the risk of embolic stroke. (See "Catheter ablation to prevent recurrent atrial fibrillation: Clinical applications".)

The left atrial appendage (LAA) is the usual source for clot that embolizes. (See 'Rationale' below.) Percutaneous approaches, often referred to as LAA exclusion procedures, that mechanically prevent embolization of LAA thrombi have been developed and tested and are discussed in this topic. In addition, some patients undergoing cardiac surgery for reasons such as valve replacement or repair or coronary artery bypass graft surgery are candidates for LAA exclusion at the time of surgery. (See 'Patients undergoing cardiac surgery' below.)

RATIONALE

Among patients with nonvalvular atrial fibrillation (AF), the vast majority of thrombus material is located within or involves the left atrial appendage (LAA). The intense fibrosis and inflammation seen in the left atrium of patients with AF, which are likely predisposing factors to thrombus formation, are particularly intense in the LAA. In addition, the fibrillating LAA is the only area within the left atrium that is comprised of pectinate muscle and can create an appropriate milieu for blood stasis and thrombus formation. It is estimated that 90 percent of left atrial thrombi are located in the LAA [2]. (See "Atrial fibrillation: Anticoagulant therapy to prevent embolization", section on 'Decide on anticoagulation'.)

The importance of the LAA in thromboembolic risk among patients with AF provides the rationale for ligation, amputation, or occlusion of the LAA, especially in patients who are candidates for but cannot receive oral anticoagulation, or those at high risk of bleeding with oral anticoagulation.

           

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Literature review current through: Nov 2016. | This topic last updated: Wed Sep 21 00:00:00 GMT 2016.
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References
Top
  1. Lane DA, Lip GY. Use of the CHA(2)DS(2)-VASc and HAS-BLED scores to aid decision making for thromboprophylaxis in nonvalvular atrial fibrillation. Circulation 2012; 126:860.
  2. Blackshear JL, Odell JA. Appendage obliteration to reduce stroke in cardiac surgical patients with atrial fibrillation. Ann Thorac Surg 1996; 61:755.
  3. Sievert H, Lesh MD, Trepels T, et al. Percutaneous left atrial appendage transcatheter occlusion to prevent stroke in high-risk patients with atrial fibrillation: early clinical experience. Circulation 2002; 105:1887.
  4. Block PC, Burstein S, Casale PN, et al. Percutaneous left atrial appendage occlusion for patients in atrial fibrillation suboptimal for warfarin therapy: 5-year results of the PLAATO (Percutaneous Left Atrial Appendage Transcatheter Occlusion) Study. JACC Cardiovasc Interv 2009; 2:594.
  5. Ostermayer SH, Reisman M, Kramer PH, et al. Percutaneous left atrial appendage transcatheter occlusion (PLAATO system) to prevent stroke in high-risk patients with non-rheumatic atrial fibrillation: results from the international multi-center feasibility trials. J Am Coll Cardiol 2005; 46:9.
  6. Holmes DR, Reddy VY, Turi ZG, et al. Percutaneous closure of the left atrial appendage versus warfarin therapy for prevention of stroke in patients with atrial fibrillation: a randomised non-inferiority trial. Lancet 2009; 374:534.
  7. Reddy VY, Doshi SK, Sievert H, et al. Percutaneous left atrial appendage closure for stroke prophylaxis in patients with atrial fibrillation: 2.3-Year Follow-up of the PROTECT AF (Watchman Left Atrial Appendage System for Embolic Protection in Patients with Atrial Fibrillation) Trial. Circulation 2013; 127:720.
  8. Reddy VY, Sievert H, Halperin J, et al. Percutaneous left atrial appendage closure vs warfarin for atrial fibrillation: a randomized clinical trial. JAMA 2014; 312:1988.
  9. Reddy VY, Holmes D, Doshi SK, et al. Safety of percutaneous left atrial appendage closure: results from the Watchman Left Atrial Appendage System for Embolic Protection in Patients with AF (PROTECT AF) clinical trial and the Continued Access Registry. Circulation 2011; 123:417.
  10. Viles-Gonzalez JF, Kar S, Douglas P, et al. The clinical impact of incomplete left atrial appendage closure with the Watchman Device in patients with atrial fibrillation: a PROTECT AF (Percutaneous Closure of the Left Atrial Appendage Versus Warfarin Therapy for Prevention of Stroke in Patients With Atrial Fibrillation) substudy. J Am Coll Cardiol 2012; 59:923.
  11. Alli O, Doshi S, Kar S, et al. Quality of life assessment in the randomized PROTECT AF (Percutaneous Closure of the Left Atrial Appendage Versus Warfarin Therapy for Prevention of Stroke in Patients With Atrial Fibrillation) trial of patients at risk for stroke with nonvalvular atrial fibrillation. J Am Coll Cardiol 2013; 61:1790.
  12. Holmes DR Jr, Kar S, Price MJ, et al. Prospective randomized evaluation of the Watchman Left Atrial Appendage Closure device in patients with atrial fibrillation versus long-term warfarin therapy: the PREVAIL trial. J Am Coll Cardiol 2014; 64:1.
  13. http://www.accessdata.fda.gov/cdrh_docs/pdf13/p130013a.pdf.
  14. Reddy VY, Möbius-Winkler S, Miller MA, et al. Left atrial appendage closure with the Watchman device in patients with a contraindication for oral anticoagulation: the ASAP study (ASA Plavix Feasibility Study With Watchman Left Atrial Appendage Closure Technology). J Am Coll Cardiol 2013; 61:2551.
  15. Meier B, Palacios I, Windecker S, et al. Transcatheter left atrial appendage occlusion with Amplatzer devices to obviate anticoagulation in patients with atrial fibrillation. Catheter Cardiovasc Interv 2003; 60:417.
  16. Tzikas A, Shakir S, Gafoor S, et al. Left atrial appendage occlusion for stroke prevention in atrial fibrillation: multicentre experience with the AMPLATZER Cardiac Plug. EuroIntervention 2016; 11:1170.
  17. Bartus K, Bednarek J, Myc J, et al. Feasibility of closed-chest ligation of the left atrial appendage in humans. Heart Rhythm 2011; 8:188.
  18. Lee RJ, Bartus K, Yakubov SJ. Catheter-based left atrial appendage (LAA) ligation for the prevention of embolic events arising from the LAA: initial experience in a canine model. Circ Cardiovasc Interv 2010; 3:224.
  19. Shetty R, Leitner JP, Zhang M. Percutaneous catheter-based left atrial appendage ligation and management of periprocedural left atrial appendage perforation with the LARIAT suture delivery system. J Invasive Cardiol 2012; 24:E289.
  20. Bartus K, Han FT, Bednarek J, et al. Percutaneous left atrial appendage suture ligation using the LARIAT device in patients with atrial fibrillation: initial clinical experience. J Am Coll Cardiol 2013; 62:108.
  21. Massumi A, Chelu MG, Nazeri A, et al. Initial experience with a novel percutaneous left atrial appendage exclusion device in patients with atrial fibrillation, increased stroke risk, and contraindications to anticoagulation. Am J Cardiol 2013; 111:869.
  22. Bartus K, Han FT, Bednarek J, et al. Percutaneous Left Atrial Appendage Suture Ligation Using the LARIAT Device in Patients With Atrial Fibrillation: Initial Clinical Experience. J Am Coll Cardiol 2013; 62:108.
  23. Price MJ, Gibson DN, Yakubov SJ, et al. Early safety and efficacy of percutaneous left atrial appendage suture ligation: results from the U.S. transcatheter LAA ligation consortium. J Am Coll Cardiol 2014; 64:565.
  24. Miller MA, Gangireddy SR, Doshi SK, et al. Multicenter study on acute and long-term safety and efficacy of percutaneous left atrial appendage closure using an epicardial suture snaring device. Heart Rhythm 2014; 11:1853.
  25. http://www.fda.gov/Safety/MedWatch/SafetyInformation/SafetyAlertsforHumanMedicalProducts/ucm454660.htm.
  26. García-Fernández MA, Pérez-David E, Quiles J, et al. Role of left atrial appendage obliteration in stroke reduction in patients with mitral valve prosthesis: a transesophageal echocardiographic study. J Am Coll Cardiol 2003; 42:1253.
  27. Katz ES, Tsiamtsiouris T, Applebaum RM, et al. Surgical left atrial appendage ligation is frequently incomplete: a transesophageal echocardiograhic study. J Am Coll Cardiol 2000; 36:468.
  28. Kanderian AS, Gillinov AM, Pettersson GB, et al. Success of surgical left atrial appendage closure: assessment by transesophageal echocardiography. J Am Coll Cardiol 2008; 52:924.
  29. Ohtsuka T, Ninomiya M, Nonaka T, et al. Thoracoscopic stand-alone left atrial appendectomy for thromboembolism prevention in nonvalvular atrial fibrillation. J Am Coll Cardiol 2013; 62:103.
  30. Ailawadi G, Gerdisch MW, Harvey RL, et al. Exclusion of the left atrial appendage with a novel device: early results of a multicenter trial. J Thorac Cardiovasc Surg 2011; 142:1002.
  31. Kirchhof P, Benussi S, Kotecha D, et al. 2016 ESC Guidelines for the management of atrial fibrillation developed in collaboration with EACTS: The Task Force for the management of atrial fibrillation of the European Society of Cardiology (ESC)Developed with the special contribution of the European Heart Rhythm Association (EHRA) of the ESCEndorsed by the European Stroke Organisation (ESO). Eur Heart J 2016.
  32. January CT, Wann LS, Alpert JS, et al. 2014 AHA/ACC/HRS guideline for the management of patients with atrial fibrillation: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines and the Heart Rhythm Society. J Am Coll Cardiol 2014; 64:e1.