Prevention of embolization prior to and after restoration of sinus rhythm in atrial fibrillation
- Robert Phang, MD, FACC, FHRS
Robert Phang, MD, FACC, FHRS
- Albany Associates in Cardiology
- Warren J Manning, MD
Warren J Manning, MD
- Section Editor — Noninvasive Cardiac Imaging and Stress Testing
- Professor of Medicine and Radiology
- Harvard Medical School
- Section Editors
- Bradley P Knight, MD, FACC
Bradley P Knight, MD, FACC
- Section Editor — Cardiac Arrhythmias
- Professor of Medicine
- Feinberg School of Medicine, Northwestern University
- Brian Olshansky, MD
Brian Olshansky, MD
- Section Editor — Cardiac Arrhythmias
- Professor of Medicine
- University of Iowa Medical Center
- N A Mark Estes, III, MD
N A Mark Estes, III, MD
- Editor-in-Chief — Cardiovascular Medicine
- Section Editor — Cardiac Arrhythmias
- Professor of Medicine
- Tufts University School of Medicine
Spontaneous or intended conversion of atrial fibrillation (AF) to sinus rhythm is associated with a short-term increase from baseline risk of clinical thromboembolism. This topic will discuss strategies that attempt to decrease this risk for patients who are not receiving long-term antithrombotic therapy.
The modalities used to perform cardioversion, long-term anticoagulation in patients with AF, and an overview of the management of AF are presented separately. (See "Atrial fibrillation: Cardioversion to sinus rhythm" and "Atrial fibrillation: Anticoagulant therapy to prevent embolization" and "Overview of atrial fibrillation".)
EXTREMELY HIGH-RISK PATIENTS
Patients with atrial fibrillation and valvular heart disease, especially rheumatic heart disease/mitral stenosis and prosthetic heart valves, are at extremely high risk of thromboembolization at all times, not just at the time of cardioversion. The approach to anticoagulation in such patients is discussed in other UpToDate topics. (See "Overview of the management of chronic mitral regurgitation", section on 'Anticoagulation' and "Antithrombotic therapy in patients with prosthetic heart valves" and "Medical management and indications for intervention for mitral stenosis", section on 'Prevention of thromboembolism'.)
RATIONALE FOR ANTICOAGULATION
All patients with atrial fibrillation (AF) have an increased risk of embolization compared to those without. (See "Atrial fibrillation: Risk of embolization", section on 'Epidemiology'.)
There is an incremental increase from the baseline risk in the immediate post-cardioversion period, whether planned or spontaneous. Most embolic events occur within 10 days of cardioversion for both warfarin and non-vitamin-K antagonist antithrombotics [1-4]. Patients undergoing cardioversion of AF of more than 48 hours duration represent a particularly high-risk group (compared to AF of shorter duration), with an embolic risk from as low as 1 to as high as 5 percent in the first month in the absence of anticoagulation [2-7]. This rate is substantially higher than the rate that would be calculated for the general population of patients with AF, in whom the yearly rate is between 1.3 and 5.1 (or higher) percent, depending on age and additional comorbidities. (See "Atrial fibrillation: Risk of embolization", section on 'Epidemiology'.)
- Berger M, Schweitzer P. Timing of thromboembolic events after electrical cardioversion of atrial fibrillation or flutter: a retrospective analysis. Am J Cardiol 1998; 82:1545.
- Nagarakanti R, Ezekowitz MD, Oldgren J, et al. Dabigatran versus warfarin in patients with atrial fibrillation: an analysis of patients undergoing cardioversion. Circulation 2011; 123:131.
- Flaker G, Lopes RD, Al-Khatib SM, et al. Efficacy and safety of apixaban in patients after cardioversion for atrial fibrillation: insights from the ARISTOTLE Trial (Apixaban for Reduction in Stroke and Other Thromboembolic Events in Atrial Fibrillation). J Am Coll Cardiol 2014; 63:1082.
- Cappato R, Ezekowitz MD, Klein AL, et al. Rivaroxaban vs. vitamin K antagonists for cardioversion in atrial fibrillation. Eur Heart J 2014; 35:3346.
- Kinch JW, Davidoff R. Prevention of embolic events after cardioversion of atrial fibrillation. Current and evolving strategies. Arch Intern Med 1995; 155:1353.
- Gentile F, Elhendy A, Khandheria BK, et al. Safety of electrical cardioversion in patients with atrial fibrillation. Mayo Clin Proc 2002; 77:897.
- Arnold AZ, Mick MJ, Mazurek RP, et al. Role of prophylactic anticoagulation for direct current cardioversion in patients with atrial fibrillation or atrial flutter. J Am Coll Cardiol 1992; 19:851.
- Manning WJ, Silverman DI, Keighley CS, et al. Transesophageal echocardiographically facilitated early cardioversion from atrial fibrillation using short-term anticoagulation: final results of a prospective 4.5-year study. J Am Coll Cardiol 1995; 25:1354.
- Weigner MJ, Thomas LR, Patel U, et al. Early cardioversion of atrial fibrillation facilitated by transesophageal echocardiography: short-term safety and impact on maintenance of sinus rhythm at 1 year. Am J Med 2001; 110:694.
- Klein AL, Grimm RA, Murray RD, et al. Use of transesophageal echocardiography to guide cardioversion in patients with atrial fibrillation. N Engl J Med 2001; 344:1411.
- Srimannarayana J, Varma RS, Satheesh S, et al. Prevalence of left atrial thrombus in rheumatic mitral stenosis with atrial fibrillation and its response to anticoagulation: a transesophageal echocardiographic study. Indian Heart J 2003; 55:358.
- Stoddard MF, Dawkins PR, Prince CR, Longaker RA. Transesophageal echocardiographic guidance of cardioversion in patients with atrial fibrillation. Am Heart J 1995; 129:1204.
- Black IW, Hopkins AP, Lee LC, Walsh WF. Evaluation of transesophageal echocardiography before cardioversion of atrial fibrillation and flutter in nonanticoagulated patients. Am Heart J 1993; 126:375.
- Black IW, Fatkin D, Sagar KB, et al. Exclusion of atrial thrombus by transesophageal echocardiography does not preclude embolism after cardioversion of atrial fibrillation. A multicenter study. Circulation 1994; 89:2509.
- Moreyra E, Finkelhor RS, Cebul RD. Limitations of transesophageal echocardiography in the risk assessment of patients before nonanticoagulated cardioversion from atrial fibrillation and flutter: an analysis of pooled trials. Am Heart J 1995; 129:71.
- Pritchett EL. Management of atrial fibrillation. N Engl J Med 1992; 326:1264.
- Connolly SJ, Ezekowitz MD, Yusuf S, et al. Dabigatran versus warfarin in patients with atrial fibrillation. N Engl J Med 2009; 361:1139.
- Botkin SB, Dhanekula LS, Olshansky B. Outpatient cardioversion of atrial arrhythmias: efficacy, safety, and costs. Am Heart J 2003; 145:233.
- Weinberg DM, Mancini J. Anticoagulation for cardioversion of atrial fibrillation. Am J Cardiol 1989; 63:745.
- Collins LJ, Silverman DI, Douglas PS, Manning WJ. Cardioversion of nonrheumatic atrial fibrillation. Reduced thromboembolic complications with 4 weeks of precardioversion anticoagulation are related to atrial thrombus resolution. Circulation 1995; 92:160.
- Israel CW, Grönefeld G, Ehrlich JR, et al. Long-term risk of recurrent atrial fibrillation as documented by an implantable monitoring device: implications for optimal patient care. J Am Coll Cardiol 2004; 43:47.
- Page RL, Wilkinson WE, Clair WK, et al. Asymptomatic arrhythmias in patients with symptomatic paroxysmal atrial fibrillation and paroxysmal supraventricular tachycardia. Circulation 1994; 89:224.
- Manning WJ, Leeman DE, Gotch PJ, Come PC. Pulsed Doppler evaluation of atrial mechanical function after electrical cardioversion of atrial fibrillation. J Am Coll Cardiol 1989; 13:617.
- Tejan-Sie SA, Murray RD, Black IW, et al. Spontaneous conversion of patients with atrial fibrillation scheduled for electrical cardioversion: an ACUTE trial ancillary study. J Am Coll Cardiol 2003; 42:1638.
- Optimal oral anticoagulant therapy in patients with nonrheumatic atrial fibrillation and recent cerebral ischemia. The European Atrial Fibrillation Trial Study Group. N Engl J Med 1995; 333:5.
- Hylek EM, Go AS, Chang Y, et al. Effect of intensity of oral anticoagulation on stroke severity and mortality in atrial fibrillation. N Engl J Med 2003; 349:1019.
- Piccini JP, Stevens SR, Lokhnygina Y, et al. Outcomes after cardioversion and atrial fibrillation ablation in patients treated with rivaroxaban and warfarin in the ROCKET AF trial. J Am Coll Cardiol 2013; 61:1998.
- Silverman DI, Manning WJ. Strategies for cardioversion of atrial fibrillation--time for a change? N Engl J Med 2001; 344:1468.
- Seto TB, Taira DA, Tsevat J, Manning WJ. Cost-effectiveness of transesophageal echocardiographic-guided cardioversion: a decision analytic model for patients admitted to the hospital with atrial fibrillation. J Am Coll Cardiol 1997; 29:122.
- Klein AL, Murray RD, Grimm RA. Role of transesophageal echocardiography-guided cardioversion of patients with atrial fibrillation. J Am Coll Cardiol 2001; 37:691.
- Manning WJ, Silverman DI, Gordon SP, et al. Cardioversion from atrial fibrillation without prolonged anticoagulation with use of transesophageal echocardiography to exclude the presence of atrial thrombi. N Engl J Med 1993; 328:750.
- Klein AL, Grimm RA, Jasper SE, et al. Efficacy of transesophageal echocardiography-guided cardioversion of patients with atrial fibrillation at 6 months: a randomized controlled trial. Am Heart J 2006; 151:380.
- Klein AL, Murray RD, Grimm RA, et al. Bleeding complications in patients with atrial fibrillation undergoing cardioversion randomized to transesophageal echocardiographically guided and conventional anticoagulation therapies. Am J Cardiol 2003; 92:161.
- 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. Circulation 2014; 130:e199.
- January CT, Wann LS, Alpert JS, et al. 2014 AHA/ACC/HRS guideline for the management of patients with atrial fibrillation: executive summary: a report of the American College of Cardiology/American Heart Association Task Force on practice guidelines and the Heart Rhythm Society. Circulation 2014; 130:2071.
- European Heart Rhythm Association, European Association for Cardio-Thoracic Surgery, Camm AJ, et al. Guidelines for the management of atrial fibrillation: the Task Force for the Management of Atrial Fibrillation of the European Society of Cardiology (ESC). Eur Heart J 2010; 31:2369.
- You JJ, Singer DE, Howard PA, et al. Antithrombotic therapy for atrial fibrillation: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines. Chest 2012; 141:e531S.
- Gallagher MM, Hennessy BJ, Edvardsson N, et al. Embolic complications of direct current cardioversion of atrial arrhythmias: association with low intensity of anticoagulation at the time of cardioversion. J Am Coll Cardiol 2002; 40:926.
- Weigner MJ, Caulfield TA, Danias PG, et al. Risk for clinical thromboembolism associated with conversion to sinus rhythm in patients with atrial fibrillation lasting less than 48 hours. Ann Intern Med 1997; 126:615.
- Airaksinen KE, Grönberg T, Nuotio I, et al. Thromboembolic complications after cardioversion of acute atrial fibrillation: the FinCV (Finnish CardioVersion) study. J Am Coll Cardiol 2013; 62:1187.
- Stoddard MF, Dawkins PR, Prince CR, Ammash NM. Left atrial appendage thrombus is not uncommon in patients with acute atrial fibrillation and a recent embolic event: a transesophageal echocardiographic study. J Am Coll Cardiol 1995; 25:452.
- Stellbrink C, Nixdorff U, Hofmann T, et al. Safety and efficacy of enoxaparin compared with unfractionated heparin and oral anticoagulants for prevention of thromboembolic complications in cardioversion of nonvalvular atrial fibrillation: the Anticoagulation in Cardioversion using Enoxaparin (ACE) trial. Circulation 2004; 109:997.
- Klein AL, Jasper SE, Katz WE, et al. The use of enoxaparin compared with unfractionated heparin for short-term antithrombotic therapy in atrial fibrillation patients undergoing transoesophageal echocardiography-guided cardioversion: assessment of Cardioversion Using Transoesophageal Echocardiography (ACUTE) II randomized multicentre study. Eur Heart J 2006; 27:2858.
- EXTREMELY HIGH-RISK PATIENTS
- RATIONALE FOR ANTICOAGULATION
- Left atrial thrombus
- Before cardioversion
- After cardioversion
- Spontaneous conversion
- AF OF MORE THAN 48 HOURS DURATION
- Anticoagulant approach
- TEE-based approach
- - Practical considerations
- AF OF LESS THAN 48 HOURS DURATION
- Urgent cardioversion
- INFORMATION FOR PATIENTS
- SUMMARY AND RECOMMENDATIONS