What are the treatment options for Atrial Fibrillation (AFib)?

Treatment for Atrial Fibrillation

The treatment of atrial fibrillation requires simultaneous implementation of three core strategies: oral anticoagulation for stroke prevention, rate or rhythm control for symptom management, and modification of cardiovascular risk factors. 1

Stroke Prevention with Anticoagulation

Oral anticoagulation is mandatory for all AFib patients with stroke risk factors, as it reduces stroke risk by 60-80% compared to placebo. 2

Risk Assessment and Anticoagulation Decision

• Calculate the CHA₂DS₂-VASc score immediately upon diagnosis (congestive heart failure, hypertension, age ≥75 years [2 points], diabetes, prior stroke/TIA/thromboembolism [2 points], vascular disease, age 65-74 years, female sex [1 point each]). 1, 3
• Initiate anticoagulation for CHA₂DS₂-VASc score ≥2 (Class I recommendation). 1, 3
• Consider anticoagulation for score of 1; no anticoagulation needed for score of 0. 4

Anticoagulant Selection

• Direct oral anticoagulants (DOACs)—apixaban, rivaroxaban, edoxaban, or dabigatran—are preferred over warfarin due to lower intracranial hemorrhage risk. 1, 2
• Use full standard doses unless specific dose-reduction criteria are met. 1
• For warfarin, maintain INR 2.0-3.0 with time in therapeutic range >70%; switch to DOAC if poor INR control or intracranial hemorrhage risk. 1
• Avoid combining anticoagulants with antiplatelet agents unless acute vascular event or interim procedural treatment is required. 1
• Continue anticoagulation regardless of rhythm status (sinus rhythm vs AFib) or success of rhythm control interventions. 1

Bleeding Risk Management

• Manage modifiable bleeding risk factors to improve safety. 1
• Do not use bleeding risk scores to decide on starting or withdrawing anticoagulants. 1

Rate Control Strategy

Rate control with beta-blockers or non-dihydropyridine calcium channel blockers is the preferred initial strategy for most patients with AFib. 1, 3

Medication Selection Based on Cardiac Function

For preserved ejection fraction (LVEF >40%):

• Beta-blockers (metoprolol, esmolol, propranolol), diltiazem, verapamil, or digoxin are first-line agents. 1, 5
• Metoprolol: 2.5-5 mg IV bolus over 2 minutes (up to 3 doses); oral maintenance 25-200 mg twice daily or 50-400 mg daily (succinate). 5
• Diltiazem: 0.25 mg/kg IV over 2 minutes (may repeat), then 5-15 mg/h infusion; oral 120-360 mg daily (extended-release). 5
• Verapamil: 5-10 mg IV over ≥2 minutes (may repeat twice), then 5 mg/h infusion; oral 180-480 mg daily (extended-release). 5

For reduced ejection fraction (LVEF ≤40%):

• Beta-blockers and/or digoxin are the only Class I recommended agents. 1, 5
• Digoxin: 0.25-0.5 mg IV over several minutes; repeat 0.25 mg every 60 minutes; oral maintenance 0.0625-0.25 mg daily. 5
• Avoid diltiazem and verapamil due to negative inotropic effects that worsen heart failure. 5, 3

Special Clinical Scenarios

• Hemodynamic instability or severely depressed LVEF: Use IV amiodarone, digoxin, esmolol, or landiolol for acute rate control. 5
• Obstructive pulmonary disease: Use diltiazem or verapamil as first-line; beta-1 selective blockers (bisoprolol) in small doses as alternative; avoid non-selective beta-blockers. 5

Rate Control Targets

• Lenient rate control with resting heart rate <110 bpm is the initial target (Class IIa recommendation). 1, 5
• Pursue stricter control (<80 bpm) only if symptoms persist despite lenient control. 5

Combination Therapy

• Consider combining different rate-controlling agents if single agent fails to achieve heart rate target or symptom control. 1, 5
• Digoxin plus beta-blocker or calcium channel blocker provides better control at rest and during exercise. 3
• Monitor carefully for bradycardia with combination therapy. 5

When Rate Control Fails

• Consider AV node ablation with pacemaker implantation for patients unresponsive to or intolerant of intensive rate and rhythm control therapy. 1, 5

Rhythm Control Strategy

Rhythm control should be considered in all suitable AFib patients to reduce symptoms and morbidity, with explicit discussion of benefits and risks. 1

Indications for Rhythm Control

• Primary indication is reduction in AFib-related symptoms and improvement in quality of life. 1
• Consider for younger patients (<65 years), first episode in otherwise healthy patients, symptomatic patients despite adequate rate control, or heart failure with reduced ejection fraction. 3, 2

Cardioversion Approach

Electrical cardioversion:

• Use immediately for hemodynamic instability. 1
• Otherwise, choose electrical or pharmacological cardioversion based on patient characteristics and preferences. 1

Anticoagulation requirements:

• If AFib duration >24 hours or unknown: provide at least 3 weeks of anticoagulation before cardioversion. 1
• Continue anticoagulation for at least 4 weeks after cardioversion. 3
• If AFib duration <48 hours: may proceed with cardioversion after initiating anticoagulation. 3

Pharmacological cardioversion:

• Flecainide (200-300 mg) or propafenone (450-600 mg) for patients without structural heart disease ("pill in the pocket" after safety established in hospital). 1

Catheter Ablation

• Consider as second-line option if antiarrhythmic drugs fail to control AFib. 1
• Consider as first-line option in patients with paroxysmal AFib to improve symptoms and slow progression to persistent AFib. 1, 2
• Recommended for patients with AFib and heart failure with reduced ejection fraction to improve quality of life, left ventricular function, and cardiovascular outcomes. 2
• Consider endoscopic or hybrid ablation if catheter ablation fails, or as alternative in persistent AFib despite antiarrhythmic drugs. 1

Antiarrhythmic Drug Selection

• Without structural heart disease: Flecainide, propafenone, or sotalol (lowest toxicity risk). 3
• With coronary artery disease: Sotalol preferred unless heart failure present. 3
• With heart failure or LVEF ≤40%: Amiodarone or dofetilide only (due to proarrhythmic risk of other agents). 3
• Avoid antiarrhythmic drugs for routine rate control in permanent AFib (Class III harm). 1, 5

Risk Factor and Comorbidity Management

Lifestyle and risk factor modification are recommended at all stages to prevent AFib onset, recurrence, and complications. 2

• Address hypertension, heart failure, diabetes, obesity, obstructive sleep apnea, physical inactivity, and high alcohol intake. 3, 2
• Weight loss and exercise are particularly important modifiable factors. 1, 2

Dynamic Reassessment

Periodically reassess therapy and evaluate for new modifiable risk factors that could slow/reverse AFib progression, increase quality of life, and prevent adverse outcomes. 1

Common Pitfalls to Avoid

• Underdosing anticoagulation or inappropriate discontinuation increases stroke risk. 3
• Using digoxin as sole agent for rate control in paroxysmal AFib is ineffective. 3
• Failing to continue anticoagulation after successful cardioversion or ablation in patients with stroke risk factors. 1, 3
• Using diltiazem or verapamil in patients with LVEF ≤40%. 5, 3
• Using AV nodal blockers (adenosine, digoxin, diltiazem, verapamil, amiodarone) in Wolff-Parkinson-White syndrome with pre-excited AFib, as they can precipitate ventricular fibrillation. 3
• Mislabeling AFib with rapid rate and wide QRS as ventricular tachycardia; consider AFib with aberrancy or pre-excitation. 3