Atrial Fibrillation Treatment
Primary Treatment Pillars
Atrial fibrillation management requires addressing three core components simultaneously: stroke prevention with anticoagulation, ventricular rate control or rhythm restoration, and management of underlying cardiovascular risk factors. 1, 2
Stroke Prevention with Anticoagulation
Risk Stratification and Anticoagulation Decision
Calculate the CHA₂DS₂-VASc score immediately (Congestive heart failure=1, Hypertension=1, Age ≥75=2, Diabetes=1, Stroke/TIA/thromboembolism=2, Vascular disease=1, Age 65-74=1, Sex category female=1). 3, 1
For patients with CHA₂DS₂-VASc score ≥2, initiate oral anticoagulation. 3, 1
For patients with CHA₂DS₂-VASc score =1, consider anticoagulation based on individual bleeding risk and patient preference. 3, 2
For low-risk patients (CHA₂DS₂-VASc score =0 in males or =1 in females where the only point is for female sex), do not prescribe anticoagulation. 3
Anticoagulant Selection
Prescribe direct oral anticoagulants (DOACs)—apixaban, dabigatran, edoxaban, or rivaroxaban—as first-line therapy over warfarin for all eligible patients. DOACs have lower intracranial hemorrhage risk compared to warfarin. 1, 2, 4
For apixaban, prescribe 5 mg twice daily; reduce to 2.5 mg twice daily only if the patient meets ≥2 of these criteria: age ≥80 years, weight ≤60 kg, or serum creatinine ≥1.5 mg/dL. 1, 5
Reserve warfarin for patients with mechanical heart valves or moderate-to-severe mitral stenosis, as DOACs are contraindicated in these populations. 1
For warfarin therapy, maintain INR between 2.0-3.0 with weekly monitoring during initiation and monthly monitoring once stable. 1, 6
Critical Anticoagulation Principles
Continue anticoagulation indefinitely based on stroke risk factors, regardless of whether the patient remains in atrial fibrillation or converts to sinus rhythm. This is a common pitfall—successful rhythm control does not eliminate stroke risk if underlying risk factors persist. 3, 1, 2
Assess bleeding risk factors and modify them (e.g., control hypertension, limit alcohol, avoid NSAIDs), but never use bleeding risk scores as a reason to withhold anticoagulation in patients with stroke risk factors. 3, 1
Monitor renal function at least annually in patients on DOACs, and more frequently if creatinine clearance is declining. 1
Rate Control Strategy
When to Choose Rate Control
Rate control is the appropriate initial strategy for most patients with atrial fibrillation, particularly those who are minimally symptomatic, elderly, or have permanent atrial fibrillation. The AFFIRM trial demonstrated no mortality or quality-of-life benefit with rhythm control compared to rate control. 3, 2
First-Line Rate Control Medications
For patients with preserved left ventricular ejection fraction (LVEF >40%), prescribe beta-blockers (metoprolol, esmolol) or non-dihydropyridine calcium channel blockers (diltiazem 60-120 mg three times daily or 120-360 mg extended-release once daily; verapamil 40-120 mg three times daily or 120-480 mg extended-release once daily) as first-line agents. 1, 2, 4
For patients with reduced ejection fraction (LVEF ≤40%), prescribe beta-blockers and/or digoxin (0.0625-0.25 mg daily); avoid diltiazem and verapamil as they worsen hemodynamic compromise. 1, 2, 4
For patients with COPD or active bronchospasm, prescribe diltiazem or verapamil and avoid beta-blockers, sotalol, and propafenone. 1
Rate Control Targets
Target lenient rate control initially: resting heart rate <110 bpm. This is non-inferior to strict control (<80 bpm) and reduces medication burden. 1, 2
Reserve strict rate control (resting heart rate <80 bpm) for patients with persistent symptoms despite lenient control. 1, 2
Combination Therapy
If monotherapy fails to achieve rate control, combine digoxin with a beta-blocker or calcium channel blocker for better control at rest and during exercise. 1, 4
Digoxin alone is inadequate for rate control during exercise or high sympathetic states; it only controls rate at rest. 1, 4
Rhythm Control Strategy
When to Choose Rhythm Control
Consider rhythm control for symptomatic patients despite adequate rate control, younger patients (<65 years), those with new-onset atrial fibrillation (<12 months), patients with heart failure where atrial fibrillation may be contributing to decompensation, or those with hemodynamic instability. 1, 2, 4
Cardioversion Approach
Immediate Cardioversion (Hemodynamically Unstable)
Perform immediate synchronized direct current cardioversion for patients with hemodynamic instability (hypotension, acute heart failure, ongoing chest pain). 1, 2
Administer intravenous amiodarone (300 mg IV diluted in 250 mL of 5% glucose over 30-60 minutes) or esmolol (0.5 mg/kg bolus over 1 minute, then 0.05-0.25 mg/kg/min infusion) for acute rate control in unstable patients. 1
Elective Cardioversion (Stable Patients)
For atrial fibrillation duration >48 hours or unknown duration, ensure therapeutic anticoagulation for ≥3 weeks before cardioversion and continue for ≥4 weeks after cardioversion. 3, 1, 2
Alternatively, perform transesophageal echocardiography to exclude left atrial thrombus, then proceed with cardioversion if negative, but still maintain anticoagulation for ≥4 weeks post-cardioversion. 4
Antiarrhythmic Drug Selection
The choice of antiarrhythmic drug depends entirely on underlying cardiac structure and comorbidities:
Patients Without Structural Heart Disease (Normal LVEF, No CAD, No LVH)
Prescribe flecainide, propafenone, or sotalol as first-line agents due to low toxicity and proarrhythmic risk. 3, 1, 2
For paroxysmal atrial fibrillation with infrequent episodes, consider "pill-in-the-pocket" approach: flecainide 200-300 mg or propafenone 450-600 mg as a single dose when symptoms occur. 3
Patients With Coronary Artery Disease
Prescribe sotalol as first-line therapy unless heart failure is present, due to its combined beta-blocking and antiarrhythmic effects. 3, 2
Consider amiodarone or dofetilide as second-line agents. 3
Avoid flecainide and propafenone entirely, as they increase risk of sustained ventricular arrhythmias in ischemic heart disease. 3
Patients With Heart Failure or LVEF ≤40%
Prescribe amiodarone or dofetilide exclusively; these are the only antiarrhythmics with proven safety in reduced ejection fraction. 3, 1, 2
All other antiarrhythmics (flecainide, propafenone, sotalol, disopyramide, procainamide, quinidine) are contraindicated due to high proarrhythmic risk. 3
Patients With Hypertension Without Left Ventricular Hypertrophy
- Prescribe flecainide or propafenone as first-line agents. 3
Patients With Hypertension With Left Ventricular Hypertrophy
- Prescribe amiodarone or dofetilide; avoid class IC agents (flecainide, propafenone) and class IA agents due to increased torsades de pointes risk. 3
Catheter Ablation
Consider catheter ablation as second-line therapy when antiarrhythmic drugs fail to control symptoms or are not tolerated. 1, 2, 4
Consider catheter ablation as first-line therapy in selected patients with symptomatic paroxysmal atrial fibrillation who prefer non-pharmacologic treatment. 1, 2
Continue anticoagulation after ablation based on CHA₂DS₂-VASc score, not rhythm status, as silent recurrences are common. 4
Special Clinical Scenarios
Wolff-Parkinson-White Syndrome With Pre-Excited Atrial Fibrillation
Perform immediate DC cardioversion if hemodynamically unstable. 1
If stable, administer IV procainamide or ibutilide; never use AV nodal blockers (adenosine, digoxin, diltiazem, verapamil, beta-blockers, amiodarone) as they can accelerate ventricular rate and precipitate ventricular fibrillation. 1
Refer for catheter ablation of the accessory pathway as definitive treatment. 1
Postoperative Atrial Fibrillation
Prescribe beta-blockers or non-dihydropyridine calcium channel blockers for rate control. 1
Consider preoperative amiodarone in high-risk cardiac surgery patients to reduce incidence. 1
Vagally-Mediated Atrial Fibrillation
- Prescribe disopyramide or flecainide as initial agents. 3
Adrenergically-Induced Atrial Fibrillation
- Prescribe beta-blockers or sotalol. 3
Thyrotoxicosis
- Prescribe beta-blockers for rate control in high catecholamine states. 1
Common Pitfalls to Avoid
Never discontinue anticoagulation after successful cardioversion or ablation if stroke risk factors persist. Silent recurrences are common and thromboembolic events can occur despite apparent sinus rhythm. 3, 2, 4
Never use digoxin as monotherapy for rate control in paroxysmal atrial fibrillation or during exercise; it only controls resting heart rate. 1, 4
Never prescribe class IC antiarrhythmics (flecainide, propafenone) in patients with coronary artery disease, prior myocardial infarction, or structural heart disease due to high risk of sustained ventricular arrhythmias. 3
Never use AV nodal blockers in Wolff-Parkinson-White syndrome with pre-excited atrial fibrillation. 1
Never underdose or inappropriately discontinue anticoagulation; this dramatically increases stroke risk. 2
Never use beta-blockers, sotalol, or propafenone in patients with active bronchospasm or severe COPD. 1