Atrial fibrillation cardioversion


 * Associate Editor(s)-In-Chief: ; Varun Kumar, M.B.B.S.

Synonyms and related keywords: AF, Afib, fib

Overview
Rhythm control methods include electrical and chemical cardioversion:
 * Electrical cardioversion involves the restoration of normal heart rhythm through the application of a DC electrical shock.
 * Chemical cardioversion is performed with drugs, such as amiodarone, dronedarone, procainamide, ibutilide, propafenone or flecainide.

The main risk of cardioversion is systemic embolization of a thrombus (blood clot) from the previously fibrillating left atrium. Cardioversion should not be performed without adequate anticoagulation in patients with more than 48 hours of atrial fibrillation. Cardioversion may be performed in instances of AF lasting more than 48 hours if a transesophogeal echocardiogram (TEE) demonstrates no evidence of clot within the heart.

Whichever method of cardioversion is used, approximately 50% of patient relapse within one year, although the continued daily use of oral antiarrhythmic drugs may extend this period. The key risk factor for relapse is duration of AF, although other risk factors that have been identified include the presence of structural heart disease, and increasing age.

==ACCF/AHA/HRS 2011 Guidelines- Pharmacological Cardioversion of Atrial Fibrillation (DO NOT EDIT) == {{cquote|

Class I
1. Administration of flecainide, dofetilide, propafenone, or ibutilide is recommended for pharmacological cardioversion of AF. (Level of Evidence: A)

Class IIa
1. Administration of amiodarone is a reasonable option for pharmacological cardioversion of AF. (Level of Evidence: A)

2. A single oral bolus dose of propafenone or flecainide (“pill-in-the-pocket”) can be administered to terminate persistent AF outside the hospital once treatment has proved safe in hospital for selected patients without sinus or AV node dysfunction, bundle branch block, QT-interval prolongation, the Brugada syndrome, or structural heart disease. Before antiarrhythmic medication is initiated, a beta blocker or non dihydropyridine calcium channel antagonist should be given to prevent rapid AV conduction in the event atrial flutter occurs. (Level of Evidence: C)

3. Administration of amiodarone can be beneficial on an outpatient basis in patients with paroxysmal or persistent AF when rapid restoration of sinus rhythm is not deemed necessary. (Level of Evidence: C)

Class IIb
1. Administration of quinidine or procainamide might be considered for pharmacological cardioversion of AF, but the usefulness of these agents is not well established. (Level of Evidence: C)

Class III
1. Digoxin and sotalol may be harmful when used for pharmacological cardioversion of AF and are not recommended. (Level of Evidence: A)

2. Quinidine, procainamide, disopyramide, and dofetilide should not be started out of hospital for conversion of AF to sinus rhythm. (Level of Evidence: B)}}

==ACCF/AHA/HRS 2011 Guidelines- Direct-Current Cardioversion of Atrial Fibrillation and Flutter (DO NOT EDIT) == {{cquote|

Class I
1. When a rapid ventricular response does not respond promptly to pharmacological measures for patients with AF with ongoing myocardial ischemia, symptomatic hypotension, angina, or HF, immediate R-wave synchronized direct-current cardioversion is recommended. (Level of Evidence: C)

2. Immediate direct-current cardioversion is recommended for patients with AF involving pre-excitation when very rapid tachycardia or hemodynamic instability occurs. (Level of Evidence: B)

3. Cardioversion is recommended in patients without hemodynamic instability when symptoms of AF are unacceptable to the patient. In case of early relapse of AF after cardioversion, repeated direct-current cardioversion attempts may be made following administration of antiarrhythmic medication. (Level of Evidence: C)

Class IIa
1. Direct-current cardioversion can be useful to restore sinus rhythm as part of a long-term management strategy for patients with AF. (Level of Evidence: B)

2. Patient preference is a reasonable consideration in the selection of infrequently repeated cardioversion for the management of symptomatic or recurrent AF. (Level of Evidence: C)

Class III
1. Frequent repetition of direct-current cardioversion is not recommended for patients who have relatively short periods of sinus rhythm between relapses of AF after multiple cardioversion procedures despite prophylactic antiarrhythmic drug therapy. (Level of Evidence: C)

2. Electrical cardioversion is contraindicated in patients with digitalis toxicity or hypokalemia. (Level of Evidence: C)}}

==ACCF/AHA/HRS 2011 Guidelines- Pharmacological Enhancement of Direct-Current Cardioversion (DO NOT EDIT) == {{cquote|

Class IIa
1. Pretreatment with amiodarone, flecainide, ibutilide, propafenone, or sotalol can be useful to enhance the success of direct-current cardioversion and prevent recurrent atrial fibrillation. (Level of Evidence: B)

2. In patients who relapse to AF after successful cardioversion, it can be useful to repeat the procedure following prophylactic administration of antiarrhythmic medication. (Level of Evidence: C)

Class IIb
1. For patients with persistent AF, administration of beta blockers, disopyramide, diltiazem, dofetilide, procainamide, or verapamil may be considered, although the efficacy of these agents to enhance the success of direct-current cardioversion or to prevent early recurrence of AF is uncertain. (Level of Evidence: C)

2. Out-of-hospital initiation of antiarrhythmic medications may be considered in patients without heart disease to enhance the success of cardioversion of AF. (Level of Evidence: C)

3. Out-of-hospital administration of antiarrhythmic medications may be considered to enhance the success of cardioversion of AF in patients with certain forms of heart disease once the safety of the drug has been verified for the patient. (Level of Evidence: C)}}

==ACCF/AHA/HRS 2011 Guidelines- Prevention of Thromboembolism in Patients With Atrial Fibrillation Undergoing Cardioversion (DO NOT EDIT) == {{cquote|

Class I
1. For patients with AF of 48-h duration or longer, or when the duration of AF is unknown, anticoagulation (INR 2.0 to 3.0) is recommended for at least 3 week prior to and 4 wk after cardioversion, regardless of the method (electrical or pharmacological) used to restore sinus rhythm. (Level of Evidence: B)

2. For patients with AF of more than 48-h duration requiring immediate cardioversion because of hemodynamic instability, heparin should be administered concurrently (unless contraindicated) by an initial intravenous bolus injection followed by a continuous infusion in a dose adjusted to prolong the activated partial thromboplastin time to 1.5 to 2 times the reference control value. Thereafter, oral anticoagulation (INR 2.0 to 3.0) should be provided for at least 4 wk, as for patients undergoing elective cardioversion. Limited data support subcutaneous administration of low molecular weight heparin in this indication. (Level of Evidence: C)

3. For patients with AF of less than 48-h duration associated with hemodynamic instability (angina pectoris, acute MI, cardiogenic shock, or pulmonary edema), cardioversion should be performed immediately without delay for prior initiation of anticoagulation. (Level of Evidence: C)

Class IIa
1. During the first 48 h after onset of AF, the need for anticoagulation before and after cardioversion may be based on the patient’s risk of thromboembolism. (Level of Evidence: C)

2. As an alternative to anticoagulation prior to cardioversion of AF, it is reasonable to perform TEE in search of thrombus in the LA or LAA. (Level of Evidence: B)

(Level of Evidence: B) Thereafter, oral anticoagulation (INR 2.0 to 3.0) is reasonable for a total anticoagulation period of at least 4 wk, as for patients undergoing elective cardioversion. (Level of Evidence: B) Limited data are available to support the subcutaneous administration of a low molecular weight heparin in this indication. (Level of Evidence: C)

(Level of Evidence: C)

3. For patients with atrial flutter undergoing cardioversion, anticoagulation can be beneficial according to the recommendations as for patients with AF. (Level of Evidence: C)}}

Vote on and Suggest Revisions to the Current Guidelines

 * The AF Living Guidelines: Vote on current recommendations and suggest revisions to the guidelines

Guideline Resources

 * ACC/AHA/ESC 2006 Guidelines for the Management of Patients With Atrial Fibrillation


 * 2011 ACCF/AHA/HRS Focused Updates Incorporated Into the ACC/AHA/ESC 2006 Guidelines for the Management of Patients With Atrial Fibrillation


 * ACC/AHA/Physician Consortium 2008 clinical performance measures for adults with nonvalvular atrial fibrillation or atrial flutter