AUTHOR: Tania B. Babar, MD
Atrial fibrillation (AF) is a supraventricular tachyarrhythmia characterized by disorganized and rapid atrial activation and uncoordinated atrial contraction. AF occurs when structural and/or electrophysiologic abnormalities alter atrial tissue to promote abnormal impulse formation and/or propagation. The ventricular rate is dependent on the conduction properties of the atrioventricular (AV) node, which can be influenced by vagal/sympathetic tone, medications, or disease of the AV node.
Multiple classification schemes have been used in the past to characterize AF. The current classification scheme (divided into three major types) used by the American College of Cardiology (ACC)/American Heart Association (AHA) guideline committee is as follows:
Paroxysmal atrial fibrillation (PAF)
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TABLE 1 CHA2DS2-VASc Score and Associated Increased Annual Risk for Stroke
C | Congestive heart failure | 1 |
H | Hypertension | 1 |
A | Age >75 yr | 1 |
D | Diabetes | 1 |
S | Stroke, TIA | 2 |
V | Vascular disease | 1 |
A | Age 65-74 yr | 1 |
Sc | Sex (female) | 1 |
Total score | Annual risk of stroke | |
0 | 0.2% | |
1 | 0.6% | |
2 | 2.2% | |
3 | 3.2% | |
4 | 4.8% | |
5 | 7.2% | |
6 | 9.7% | |
7 | 11.2% | |
8 | 10.8% | |
9 | 12.2% |
TIA, Transient ischemic attack.
From Warshaw G et al: Hams primary care geriatrics, ed 7, Philadelphia, 2022, Elsevier.
Ca2+, Ionized Calcium; RAAS, Renin-Angiotensin-Aldosterone System.
From Parrillo JE, Dellinger RP: Critical care medicine, principles of diagnosis and management in the adult, ed 5, Philadelphia, 2019, Elsevier.
Drugs are Listed Alphabetically. A-Blockers Should Be Instituted after Stabilization of Patients with Decompensated Heart Failure (HF). The Choice of -Blocker (E.g., Cardioselective) Depends on the Patients Clinical Condition. Bdigoxin is Not Usually First-Line Therapy. It May Be Combined with a -Blocker and/or a Nondihydropyridine Calcium Channel Blocker When Ventricular Rate Control is Insufficient and May Be Useful in Patients with Heart Failure. Cin Part Because of Concern over its Side Effect Profile, Use of Amiodarone for Chronic Control of Ventricular Rate Should Be Reserved for Patients Who Do Not Respond to or are Intolerant of -Blockers or Nondihydropyridine Calcium Antagonists. COPD, Chronic Obstructive Pulmonary Disease; CV, Cardiovascular; HF, Heart Failure; Hfpef, Heart Failure with Preserved Ejection Fraction; LV, Left Ventricular. (From Parrillo Je, Dellinger Rp: Critical Care Medicine, Principles of Diagnosis and Management in the Adult, Ed 5, Philadelphia, 2019, Elsevier.)
The evaluation of atrial fibrillation involves diagnosis, determination of the etiology, and classification of the arrhythmia. A minimal evaluation includes a history and physical examination, ECG, transthoracic echocardiogram, and case-specific laboratory work to rule out secondary AF.
Note that F Waves are Variable in Rate, Shape, and Amplitude, Whereas Flutter Waves are Constant in Rate and All Aspects of Morphology. Shown are Leads V1 and II.
From Zipes DP: Braunwalds heart disease, a textbook of cardiovascular medicine, ed 11, Philadelphia, 2019, Elsevier.
A, The Ventricular Rhythm is Irregular, Indicating that It is the Result of Conducted Atrial beats. B, The Ventricular Rhythm is Regular, Consistent with the Presence of Complete Atrioventricular (AV) Block and a Regular Junctional Escape Rhythm.
From Issa Z et al: Clinical arrhythmology and electrophysiology, ed 2, Philadelphia, 2012, Saunders Elsevier.
TABLE 4 ACC/AHA Recommendations for Maintenance of Sinus Rhythm in Patients with Atrial Fibrillation
Class | Indication | Level of Evidence |
---|---|---|
Class I (indicated) | Before initiation of antiarrhythmic drug therapy, treatment of precipitating or reversible causes of AF is recommended. | C |
Catheter ablation by an experienced operator is useful in selected patients with symptomatic paroxysmal AF who have failed treatment with an antiarrhythmic drug and have a normal or mildly dilated left atrium and normal or mildly reduced left ventricular function. | A | |
Class IIa (reasonable) | Pharmacologic therapy can be useful in patients with AF to maintain sinus rhythm and to prevent tachycardia-induced cardiomyopathy. | C |
Infrequent, well-tolerated recurrence of AF is reasonable as a successful outcome of antiarrhythmic drug therapy. | C | |
Outpatient initiation of antiarrhythmic drug therapy is reasonable in patients with AF who have no associated heart disease when the agent is well tolerated. | C | |
In patients with lone AF without structural heart disease, initiation of propafenone or flecainide can be beneficial on an outpatient basis in patients with paroxysmal AF who are in sinus rhythm at the time of drug initiation. | B | |
Sotalol can be beneficial in outpatients in sinus rhythm with little or no heart disease, prone to paroxysmal AF, if the baseline uncorrected QT interval is shorter than 460 milliseconds, serum electrolyte values are normal, and risk factors associated with class III drug-related proarrhythmia are not present. | C | |
Catheter ablation is a reasonable treatment of symptomatic persistent AF. | A | |
Class IIb (may be considered) | Catheter ablation may be reasonable for patients with symptomatic paroxysmal AF and significant left atrial dilation or significant left ventricular dysfunction. | A |
Class III (not indicated) | Antiarrhythmic therapy with a particular drug is not recommended for maintenance of sinus rhythm in patients with AF who have well-defined risk factors for proarrhythmia with that agent. | A |
Pharmacologic therapy is not recommended for maintenance of sinus rhythm in patients with advanced sinus node disease or AV node dysfunction unless they have a functioning electronic cardiac pacemaker. | C |
ACC, American College of Cardiology; AF, atrial fibrillation; AHA, American Heart Association.
From Zipes DP: Braunwalds heart disease, a textbook of cardiovascular medicine, ed 11, Philadelphia, 2019, Elsevier.
TABLE 3 ACC/AHA Recommendations for Pharmacologic Rate Control of Atrial Fibrillation
Class | Indication | Level of Evidence |
---|---|---|
Class I (indicated) | Measurement of the heart rate at rest and control of the rate with pharmacologic agents (either a beta-blocker or nondihydropyridine calcium channel antagonist, in most cases) are recommended for patients with persistent or permanent AF. | B |
In the absence of preexcitation, intravenous administration of beta-blockers (esmolol, metoprolol, or propranolol) or nondihydropyridine calcium channel antagonists (verapamil, diltiazem) is recommended to slow the ventricular response to AF in the acute setting, exercising caution in patients with hypotension or heart failure. | B | |
Intravenous administration of digoxin or amiodarone is recommended to control heart rate in patients with AF and heart failure who do not have an accessory pathway. | B | |
In patients who experience symptoms related to AF during activity, the adequacy of heart rate control should be assessed during exercise, adjusting pharmacologic treatment as necessary to keep the rate in the physiologic range. | C | |
Digoxin is effective after oral administration to control the heart rate at rest in patients with AF and is indicated for patients with heart failure or left ventricular dysfunction and for sedentary individuals. | C | |
Class IIa (reasonable) | A combination of digoxin and either a beta-blocker or nondihydropyridine calcium channel antagonist is reasonable to control the heart rate both at rest and during exercise in patients with AF. The choice of medication should be individualized and the dose modulated to avoid bradycardia. | B |
It is reasonable to use ablation of the AV node or accessory pathway to control heart rate when pharmacologic therapy is insufficient or associated with side effects. | B | |
Intravenous amiodarone can be useful to control heart rate in patients with AF when other measures are unsuccessful or contraindicated. | C | |
When electrical cardioversion is not necessary in patients with AF and an accessory pathway, intravenous procainamide or ibutilide is a reasonable alternative. | C | |
Class IIb (may be considered) | When the ventricular rate cannot be adequately controlled both at rest and during exercise in patients with AF by a beta-blocker, nondihydropyridine calcium channel antagonist, or digoxin, alone or in combination, oral amiodarone may be administered to control the heart rate. | C |
Intravenous procainamide, disopyramide, ibutilide, or amiodarone may be considered for hemodynamically stable patients with AF involving conduction over an accessory pathway. | B | |
When the rate cannot be controlled with pharmacologic agents or tachycardia-mediated cardiomyopathy is suspected, catheter-directed ablation of the AV node may be considered in patients with AF to control the heart rate. | C | |
Class III (not indicated) | Strict rate control (<80 beats/min at rest or <110 beats/min during 6-min walk) is not beneficial compared to a resting rate <110 beats/min in asymptomatic patients with persistent AF and an ejection fraction >40%, although uncontrolled tachycardia can lead to reversible left ventricular dysfunction over time. | B |
Digitalis should not be used as the sole agent to control the rate of ventricular response in patients with paroxysmal AF. | B | |
Catheter ablation of the AV node should not be attempted without a prior trial of medication to control the ventricular rate in patients with AF. | C | |
In patients with decompensated heart failure and AF, intravenous administration of a nondihydropyridine calcium channel antagonist may exacerbate hemodynamic compromise and is not recommended. | C | |
Intravenous administration of digitalis glycosides or nondihydropyridine calcium channel antagonists to patients with AF and a preexcitation syndrome may paradoxically accelerate the ventricular response and is not recommended. | C |
ACC, American College of Cardiology; AF, atrial fibrillation; AHA, American Heart Association; AV, atrioventricular.
From Zipes DP: Braunwalds heart disease, a textbook of cardiovascular medicine, ed 11, Philadelphia, 2019, Elsevier.
TABLE 2 ACC/AHA Recommendations for Cardioversion of Atrial Fibrillation
Class | Indication | Level of Evidence |
---|---|---|
Pharmacologic Cardioversion | ||
Class I (indicated) | Administration of flecainide, dofetilide, propafenone, or ibutilide is recommended for pharmacologic cardioversion of AF. | A |
Class IIa (reasonable) | Administration of amiodarone is a reasonable option for pharmacologic cardioversion of AF. | A |
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 the 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 nondihydropyridine calcium channel antagonist should be given to prevent rapid AV conduction in the event atrial flutter occurs. | C | |
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. | C | |
Class IIb (may be considered) | Administration of quinidine or procainamide might be considered for pharmacologic cardioversion of AF, but the usefulness of these agents is not well established. | C |
Class III (not indicated) | Digoxin and sotalol may be harmful when used for pharmacologic cardioversion of AF and are not recommended. | A |
Quinidine, procainamide, disopyramide, and dofetilide should not be started out of the hospital for conversion of AF to sinus rhythm. | B | |
Direct-Current Cardioversion | ||
Class I (indicated) | When a rapid ventricular response does not respond promptly to pharmacologic measures for patients with AF with ongoing myocardial ischemia, symptomatic hypotension, angina, or heart failure, immediate R wave-synchronized direct-current cardioversion is recommended. | C |
Immediate direct-current cardioversion is recommended for patients with AF involving preexcitation when very rapid tachycardia or hemodynamic instability occurs. | B | |
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 after administration of antiarrhythmic medication. | C | |
Class IIa (reasonable) | Direct-current cardioversion can be useful to restore sinus rhythm as part of a long-term management strategy for patients with AF. | B |
The patients preference is a reasonable consideration in the selection of infrequently repeated cardioversions for the management of symptomatic or recurrent AF. | C | |
Class III (not indicated) | 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. | C |
Electrical cardioversion is contraindicated in patients with digitalis toxicity or hypokalemia. | C | |
Pharmacologic Enhancement of Direct-Current Cardioversion | ||
Class IIa (reasonable) | Pretreatment with amiodarone, flecainide, ibutilide, propafenone, or sotalol can be useful to enhance the success of direct-current cardioversion and to prevent recurrent AF. | B |
In patients who relapse to AF after successful cardioversion, it can be useful to repeat the procedure after prophylactic administration of antiarrhythmic medication. | C | |
Class IIb (may be considered) | 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. | C |
Out-of-hospital initiation of antiarrhythmic medications may be considered in patients without heart disease to enhance the success of cardioversion of AF. | C | |
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. | C | |
Prevention of Thromboembolism in Patients with Atrial Fibrillation Undergoing Cardioversion | ||
Class I (indicated) | For patients with AF of 48-h duration or longer, or when the duration of AF is unknown, anticoagulation (INR, 2.0-3.0) is recommended for at least 3 wk before and 4 wk after cardioversion, regardless of the method (electrical or pharmacologic) used to restore sinus rhythm. | B |
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 1.5-2× the reference control value. Thereafter, oral anticoagulation (INR, 2.0-3.0) 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. | C | |
For patients with AF of less than 48-h duration associated with hemodynamic instability (angina pectoris, myocardial infarction, shock, or pulmonary edema), cardioversion should be performed immediately, without delay, for prior initiation of anticoagulation. | C | |
Class IIa (reasonable) | During the 48 h after onset of AF, the need for anticoagulation before and after cardioversion may be based on the patients risk of thromboembolism. | C |
As an alternative to anticoagulation before cardioversion of AF, it is reasonable to perform transesophageal echocardiography in search of thrombus in the left atrium or left atrial appendage. | B | |
a. For patients with no identifiable thrombus, cardioversion is reasonable immediately after anticoagulation with unfractionated heparin (e.g., initiated by intravenous bolus injection and an infusion continued at a dose adjusted to prolong the activated partial thromboplastin time to 1.5-2× the control value until oral anticoagulation has been established with an oral vitamin K antagonist [e.g., warfarin] as evidenced by an INR ≥2.0). | B | |
Thereafter, continuation of oral anticoagulation (INR, 2.0-3.0) is reasonable for a total anticoagulation period of at least 4 wk, as for patients undergoing elective cardioversion. | B | |
Limited data are available to support the subcutaneous administration of a low-molecular-weight heparin in this indication. | C | |
b. For patients in whom thrombus is identified by transesophageal echocardiography, oral anticoagulation (INR, 2.0-3.0) is reasonable for at least 3 wk before and 4 wk after restoration of sinus rhythm, and a longer period of anticoagulation may be appropriate even after apparently successful cardioversion because the risk of thromboembolism often remains elevated in such cases. | C | |
For patients with atrial flutter undergoing cardioversion, anticoagulation can be beneficial according to the recommendations as for patients with AF. | C |
ACC, American College of Cardiology; AF, atrial fibrillation; AHA, American Heart Association; AV, atrioventricular; INR, international normalized ratio.
From Zipes DP: Braunwalds heart disease, a textbook of cardiovascular medicine, ed 11, Philadelphia, 2019, Elsevier.
Drugs are Listed Alphabetically and Not in Order of Suggested Use. The Seriousness of Heart Disease Progresses from Left to Right, and Selection of Therapy in Patients with Multiple Conditions Depends on the Most Serious Condition Present. LVH, Left Ventricular Hypertrophy.
From Wann LS et al: 2011 ACCF/AHA/HRS Focused update on the management of patients with atrial fibrillation [updating the 2006 guideline]: a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines, J Am Coll Cardiol 57[2]:223-242, 2011.
HAS-BLED Risk Factors | Score | ||
---|---|---|---|
Hypertension | 1 | ||
Abnormal liver function | 1 | ||
Abnormal renal function | 1 | ||
Stroke | 1 | ||
Bleeding | 1 | ||
Labile INRs | 1 | ||
Elderly (age >65) | 1 | ||
Drugs | 1 | ||
Alcohol | 1 |
HAS-BLED is the most validated bleeding score for patients with AF in whom antithrombotic therapy is indicated. When HAS-BLED score ≥3, caution and regular review are appropriate, as well as efforts to correct the potentially reversible risk factors for bleeding. INRs, International normalized ratio.
From Ronco C et al: Critical care nephrology, ed 3, Philadelphia, 2019, Elsevier.
TABLE 6 Comparison of the Features of the Direct Oral Anticoagulants
Dabigatran | Rivaroxaban | Apixaban | Edoxaban | |
---|---|---|---|---|
Target | Thrombin (IIa) | Factor Xa | Factor Xa | Factor Xa |
Active Drug | No | Yes | Yes | Yes |
Onset Time (h) | 0.5-2 | 2-4 | 3-4 | 1-3 |
Half-Life (h) | 12-17 | 5-13 | ∼12 | 9-11 |
Renal Excretion (%) | 80 | 33 | 27 | 50 |
Reversal Agent | Idarucizumab 5 g IV bolus | Andexanet alfa or PCC | Andexanet alfa or PCC | Andexanet alfa or PCC |
IV, Intravenous; PCC, prothrombin complex concentrate.
From Hoffman R et al: Hematology, basic principles and practice, ed 7, Philadelphia, 2018, Elsevier.
TABLE 5 ACC/AHA Recommendations for Prevention of Thromboembolism in Atrial Fibrillation
Class | Indication | Level of Evidence |
---|---|---|
Class I (indicated) | Antithrombotic therapy to prevent thromboembolism is recommended for all patients with AF, except those with lone AF or contraindications. | A |
The selection of the antithrombotic agent should be based on the absolute risks of stroke and bleeding and the relative risk and benefit for a given patient. | A | |
For patients without mechanical heart valves at high risk of stroke, chronic oral anticoagulant therapy with a vitamin K antagonist is recommended in a dose adjusted to achieve the target intensity international normalized ratio (INR) of 2.0-3.0 unless contraindicated. Factors associated with highest risk for stroke in patients with AF are prior thromboembolism (stroke, transient ischemic attack, or systemic embolism) and rheumatic mitral stenosis. | A | |
Anticoagulation with a vitamin K antagonist is recommended for patients with more than one moderate risk factor. Such factors include age ≥75 yr, hypertension, heart failure, impaired left ventricular systolic function (ejection fraction ≤35% or fractional shortening <25%), and diabetes mellitus. | A | |
INR should be determined at least weekly during initiation of therapy and monthly when anticoagulation is stable. | A | |
Dabigatran is a useful alternative to warfarin in patients with AF and risk factors for stroke who do not have a prosthetic heart valve or significant valve disease, a creatinine clearance <15 mL/min, or advanced liver disease. | B | |
Aspirin, 81-325 mg daily, is recommended as an alternative to vitamin K antagonists in low-risk patients or in those with contraindications to oral anticoagulation. | A | |
For patients with AF who have mechanical heart valves, the target intensity of anticoagulation should be based on the type of prosthesis, maintaining an INR of at least 2.5. | B | |
Antithrombotic therapy is recommended for patients with atrial flutter as for those with AF. | C | |
Class IIa (reasonable) | For primary prevention of thromboembolism in patients with nonvalvular AF who have just one of the following validated risk factors, antithrombotic therapy with either aspirin or a vitamin K antagonist is reasonable, based on an assessment of the risk of bleeding complications, ability to safely sustain adjusted chronic anticoagulation, and the patients preferences: Age ≥75 yr (especially in female patients), hypertension, heart failure, impaired left ventricular function, or diabetes mellitus. | A |
For patients with nonvalvular AF who have one or more of the following less well-validated risk factors, antithrombotic therapy with either aspirin or a vitamin K antagonist is reasonable for prevention of thromboembolism: Age 65-74 yr, female gender, or coronary artery disease. The choice of agent should be based on the risk of bleeding complications, ability to sustain adjusted chronic anticoagulation, and the patients preferences. | B | |
It is reasonable to select antithrombotic therapy by the same criteria irrespective of the pattern (i.e., paroxysmal, persistent, or permanent) of AF. | B | |
In patients with AF who do not have mechanical prosthetic heart valves, it is reasonable to interrupt anticoagulation for up to 1 wk without substituting heparin for surgical or diagnostic procedures that carry a risk of bleeding. | C | |
It is reasonable to reevaluate the need for anticoagulation at regular intervals. | C | |
Class IIb (may be considered) | In patients ≥75 yr at increased risk of bleeding but without frank contraindications to oral anticoagulant therapy, and in other patients with moderate risk factors for thromboembolism who are unable to safely tolerate anticoagulation at the standard intensity of INR 2.0-3.0, a lower INR target of 2.0 (range, 1.6-2.5) may be considered for prevention of ischemic stroke and systemic embolism. | C |
When surgical procedures require interruption of oral anticoagulant therapy for longer than 1 wk in high-risk patients, unfractionated heparin may be administered or low-molecular-weight heparin given by subcutaneous injection, although the efficacy of these alternatives in this situation is uncertain. | C | |
After percutaneous coronary intervention or revascularization surgery in patients with AF, low-dose aspirin (<100 mg/day) and/or clopidogrel (75 mg/day) may be given concurrently with anticoagulation to prevent myocardial ischemic events, but these strategies have not been thoroughly evaluated and are associated with an increased risk of bleeding. | C | |
In patients undergoing percutaneous coronary intervention, anticoagulation may be interrupted to prevent bleeding at the site of peripheral arterial puncture, but the vitamin K antagonist should be resumed as soon as possible after the procedure and the dose adjusted to achieve an INR in the therapeutic range. Aspirin may be given temporarily during the hiatus, but the maintenance regimen should then consist of the combination of clopidogrel, 75 mg daily, plus warfarin (INR, 2.0-3.0). Clopidogrel should be given for a minimum of 1 mo after implantation of a bare-metal stent, at least 3 mo for a sirolimus-eluting stent, at least 6 mo for a paclitaxel-eluting stent, and 12 mo or longer in selected patients, following which warfarin may be continued as monotherapy in the absence of a subsequent coronary event. When warfarin is given in combination with clopidogrel or low-dose aspirin, the dose intensity must be carefully regulated. | C | |
In patients with AF younger than 60 yr without heart disease or risk factors for thromboembolism (lone AF), the risk of thromboembolism is low without treatment, and the effectiveness of aspirin for primary prevention of stroke relative to the risk of bleeding has not been established. | C | |
In patients with AF who sustain ischemic stroke or systemic embolism during treatment with low-intensity anticoagulation (INR, 2.0-3.0), rather than add an antiplatelet agent, it may be reasonable to raise the intensity of the anticoagulation to a maximum target INR of 3.0-3.5. | C | |
Clopidogrel plus aspirin may be considered in patients who cannot tolerate or who refuse an oral anticoagulant. | B | |
Class III (not indicated) | Long-term anticoagulation with a vitamin K antagonist is not recommended for primary prevention of stroke in patients younger than 60 yr without heart disease (lone AF) or any risk factors for thromboembolism. | C |
ACC, American College of Cardiology; AF, atrial fibrillation; AHA, American Heart Association.
From Zipes DP: Braunwalds heart disease, a textbook of cardiovascular medicine, ed 11, Philadelphia, 2019, Elsevier.
TABLE 8 ACC/AHA Recommendations for Special Considerations in Atrial Fibrillation
Class | Indication | Level of Evidence |
---|---|---|
Postoperative Atrial Fibrillation | ||
Class I (indicated) | Unless contraindicated, treatment with an oral beta-blocker to prevent postoperative AF is recommended for patients undergoing cardiac surgery. | A |
Administration of AV nodal blocking agents is recommended to achieve rate control in patients who develop postoperative AF. | B | |
Class IIa (reasonable) | Preoperative administration of amiodarone reduces the incidence of AF in patients undergoing cardiac surgery and represents appropriate prophylactic therapy for patients at high risk for postoperative AF. | A |
It is reasonable to restore sinus rhythm by pharmacologic cardioversion with ibutilide or direct-current cardioversion in patients who develop postoperative AF, as advised for nonsurgical patients. | B | |
It is reasonable to administer antiarrhythmic medications in an attempt to maintain sinus rhythm in patients with recurrent or refractory postoperative AF, as recommended for other patients who develop AF. | B | |
It is reasonable to administer antithrombotic medication in patients who develop postoperative AF, as recommended for nonsurgical patients. | B | |
Class IIb (may be considered) | Prophylactic administration of sotalol may be considered for patients at risk for development of AF after cardiac surgery. | B |
Acute Myocardial Infarction | ||
Class I (indicated) | Direct-current cardioversion is recommended for patients with severe hemodynamic compromise or intractable ischemia, or when adequate rate control cannot be achieved with pharmacologic agents in patients with acute myocardial infarction and AF. | C |
Intravenous administration of amiodarone is recommended to slow a rapid ventricular response to AF and to improve left ventricular function in patients with acute myocardial infarction. | C | |
Intravenous beta-blockers and nondihydropyridine calcium antagonists are recommended to slow a rapid ventricular response to AF in patients with acute myocardial infarction who do not display clinical left ventricular dysfunction, bronchospasm, or AV block. | C | |
For patients with AF and acute myocardial infarction, administration of unfractionated heparin by either continuous intravenous infusion or intermittent subcutaneous injection is recommended in a dose sufficient to prolong the activated partial thromboplastin time to 1.5-2× the control value, unless contraindications to anticoagulation exist. | C | |
Class IIa (reasonable) | Intravenous administration of digitalis is reasonable to slow a rapid ventricular response and to improve left ventricular function in patients with acute myocardial infarction and AF associated with severe left ventricular dysfunction and heart failure. | C |
Class III (not indicated) | The administration of class IC antiarrhythmic drugs is not recommended in patients with AF in the setting of acute myocardial infarction. | C |
Management of Atrial Fibrillation Associated with Wolff-Parkinson-White (WPW) Preexcitation Syndrome | ||
Class I (indicated) | Catheter ablation of the accessory pathway is recommended for symptomatic patients with AF who have WPW syndrome, particularly those with syncope due to rapid heart rate or those with a short bypass tract refractory period. | B |
Immediate direct-current cardioversion is recommended to prevent ventricular fibrillation in patients with a short anterograde bypass tract refractory period in whom AF occurs with a rapid ventricular response associated with hemodynamic instability. | B | |
Intravenous procainamide or ibutilide is recommended to restore sinus rhythm in patients with WPW in whom AF occurs without hemodynamic instability in association with a wide QRS complex on the electrocardiogram (≥120-msec duration) or with a rapid preexcited ventricular response. | C | |
Class IIa (reasonable) | Intravenous flecainide or direct-current cardioversion is reasonable when very rapid ventricular rates occur in patients with AF involving conduction over an accessory pathway. | B |
Class IIb (may be considered) | It may be reasonable to administer intravenous quinidine, procainamide, disopyramide, ibutilide, or amiodarone to hemodynamically stable patients with AF involving conduction over an accessory pathway. | B |
Class III (not indicated) | Intravenous administration of digitalis glycosides or nondihydropyridine calcium channel antagonists is not recommended in patients with WPW syndrome who have preexcited ventricular activation during AF. | B |
Hyperthyroidism | ||
Class I (indicated) | Administration of a beta-blocker is recommended to control the rate of ventricular response in patients with AF complicating thyrotoxicosis, unless contraindicated. | B |
In circumstances when a beta-blocker cannot be used, administration of a nondihydropyridine calcium channel antagonist (diltiazem or verapamil) is recommended to control the ventricular rate in patients with AF and thyrotoxicosis. | B | |
In patients with AF associated with thyrotoxicosis, oral anticoagulation (INR, 2.0-3.0) is recommended to prevent thromboembolism, as recommended for AF patients with other risk factors for stroke. | C | |
Once a euthyroid state is restored, recommendations for antithrombotic prophylaxis are the same as for patients without hyperthyroidism. | C | |
Management of Atrial Fibrillation during Pregnancy | ||
Class I (indicated) | Digoxin, a beta-blocker, or a nondihydropyridine calcium channel antagonist is recommended to control the rate of ventricular response in pregnant patients with AF. | C |
Direct-current cardioversion is recommended in pregnant patients who become hemodynamically unstable because of AF. | C | |
Protection against thromboembolism is recommended throughout pregnancy for all patients with AF (except those with lone AF and/or low thromboembolic risk). Therapy (anticoagulant or aspirin) should be chosen according to the stage of pregnancy. | C | |
Class IIb (may be considered) | Administration of heparin may be considered during the first trimester and last month of pregnancy for patients with AF and risk factors for thromboembolism. Unfractionated heparin may be administered either by continuous intravenous infusion in a dose sufficient to prolong the activated partial thromboplastin time to 1.5-2× the control value or by intermittent subcutaneous injection in a dose of 10,000-20,000 units every 12 h, adjusted to prolong the midinterval (6 h after injection) activated partial thromboplastin time to 1.5× control. | B |
Despite the limited data available, subcutaneous administration of low-molecular-weight heparin may be considered during the first trimester and last month of pregnancy for patients with AF and risk factors for thromboembolism. | C | |
Administration of an oral anticoagulant may be considered during the second trimester for pregnant patients with AF at high thromboembolic risk. | C | |
Administration of quinidine or procainamide may be considered to achieve pharmacologic cardioversion in hemodynamically stable patients who develop AF during pregnancy. | C | |
Management of Atrial Fibrillation in Patients with Hypertrophic Cardiomyopathy (HCM) | ||
Class I (indicated) | Oral anticoagulation (INR, 2.0-3.0) is recommended in patients with HCM who develop AF, as for other patients at high risk of thromboembolism. | B |
Class IIa (may be considered) | Antiarrhythmic medications can be useful to prevent recurrent AF in patients with HCM. Available data are insufficient to recommend one agent over another in this situation, but (a) disopyramide combined with a beta-blocker or nondihydropyridine calcium channel antagonist or (b) amiodarone alone is generally preferred. | C |
Management of Atrial Fibrillation in Patients with Pulmonary Disease | ||
Class I (indicated) | Correction of hypoxemia and acidosis is the recommended primary therapeutic measure for patients who develop AF during an acute pulmonary illness or exacerbation of chronic pulmonary disease. | C |
A nondihydropyridine calcium channel antagonist (diltiazem or verapamil) is recommended to control the ventricular rate in patients with obstructive pulmonary disease who develop AF. | C | |
Direct-current cardioversion should be attempted in patients with pulmonary disease who become hemodynamically unstable as a consequence of AF. | C | |
Class III (not indicated) | Theophylline and beta-adrenergic agonist agents are not recommended for patients with bronchospastic lung disease who develop AF. | C |
Beta-blockers, sotalol, propafenone, and adenosine are not recommended in patients with obstructive lung disease who develop AF. | C |
ACC, American College of Cardiology; AF, atrial fibrillation; AHA, American Heart Association; AV, atrioventricular; INR, international normalized ratio.
From Zipes DP: Braunwalds heart disease, a textbook of cardiovascular medicine, ed 11, Philadelphia, 2019, Elsevier.
The number of patients anticoagulated in the United States is approximately half the number that should be anticoagulated for AF, resulting in a large burden of stroke. The exact burden of AF needed to trigger the need for anticoagulation is not known, though recent pacemaker trials have suggested that as little as 6 min confers significant stroke risk. Reversal agents for the new class of anticoagulation are now available: Idarucizumab for reversal of dabigatran; andexanet alfa for reversal of apixaban and rivaroxaban.
The American Academy of Family Physicians and the American College of Physicians provide the following recommendations for the management of newly detected AF: