What is the recommended anticoagulation therapy for patients with atrial fibrillation (AF)?

From the Guidelines

The recommended anticoagulation therapy for patients with atrial fibrillation (AF) is based on stroke risk assessment using the CHA₂DS₂-VASc score, with direct oral anticoagulants (DOACs) preferred over warfarin for most patients. For patients with a score of 2 or higher in men or 3 or higher in women, oral anticoagulation is strongly recommended 1. The options for anticoagulation include:

• Warfarin (Class 1, Level of Evidence: A)
• Dabigatran (Class 1, Level of Evidence: B)
• Rivaroxaban (Class 1, Level of Evidence: B)
• Apixaban (Class 1, Level of Evidence: B)
• Edoxaban (Class 1, Level of Evidence: B-R)

DOACs are recommended over warfarin in DOAC-eligible patients with AF, except with moderate or severe mitral stenosis or a mechanical heart valve (Class 1, Level of Evidence: A) 1. The CHA2DS2-VASc score is recommended for assessment of stroke risk in patients with AF, except with moderate or severe mitral stenosis or a mechanical heart valve (Class 1, Level of Evidence: B) 1.

Some key points to consider when choosing an anticoagulant include:

• Dose adjustments for patients with renal impairment: apixaban 2.5mg twice daily if two of three criteria are met (age ≥80, weight ≤60kg, creatinine ≥1.5mg/dL); rivaroxaban 15mg daily if CrCl 15-50mL/min; edoxaban 30mg daily if CrCl 15-50mL/min; and dabigatran 75-110mg twice daily with severe renal impairment.
• Warfarin remains an option, particularly for patients with mechanical heart valves, moderate-to-severe mitral stenosis, or severe kidney disease, with a target INR of 2-3.
• Anticoagulation works by preventing blood clot formation in the left atrial appendage, which is the source of most cardioembolic strokes in AF.
• The therapy should be considered lifelong in most cases as the stroke risk persists as long as AF is present.

It's worth noting that the 2021 update to the 2016 ACC/AHA clinical performance and quality measures for adults with atrial fibrillation or atrial flutter provides the most recent and highest quality evidence for anticoagulation therapy in patients with AF 1.

From the FDA Drug Label

Oral anticoagulation therapy with warfarin is recommended in patients with persistent or paroxysmal AF (PAF) (intermittent AF) at high risk of stroke (i.e., having any of the following features: prior ischemic stroke, transient ischemic attack, or systemic embolism, age >75 years, moderately or severely impaired left ventricular systolic function and/or congestive heart failure, history of hypertension, or diabetes mellitus) In patients with persistent AF or PAF, age 65 to 75 years, in the absence of other risk factors, but who are at intermediate risk of stroke, antithrombotic therapy with either oral warfarin or aspirin, 325 mg/day, is recommended.

The recommended anticoagulation therapy for patients with atrial fibrillation (AF) is oral warfarin for those at high risk of stroke, with a target INR of 2.0-3.0. For patients at intermediate risk of stroke, antithrombotic therapy with either oral warfarin or aspirin is recommended 2.

• High-risk patients: prior ischemic stroke, transient ischemic attack, or systemic embolism, age >75 years, moderately or severely impaired left ventricular systolic function and/or congestive heart failure, history of hypertension, or diabetes mellitus
• Intermediate-risk patients: age 65 to 75 years, in the absence of other risk factors

From the Research

Anticoagulation Therapy for Atrial Fibrillation

The recommended anticoagulation therapy for patients with atrial fibrillation (AF) depends on their stroke risk, which can be assessed using the CHA2DS2-VASc score 3, 4, 5.

• For patients with a CHA2DS2-VASc score of at least 2 in men or 3 in women, anticoagulation with warfarin or direct oral anticoagulants (DOACs) is recommended 3.
• DOACs, such as dabigatran, apixaban, and rivaroxaban, are typically the first-line therapy for stroke prevention in AF patients 6, 3.
• The choice of anticoagulant should be individualized based on the patient's risk of stroke and bleeding, as well as their personal preferences and cost considerations 4.
• For patients with subclinical atrial fibrillation, apixaban has been shown to reduce the risk of stroke and systemic embolism compared to aspirin, but increases the risk of major bleeding 7, 5.
• The benefits and risks of anticoagulation therapy should be carefully weighed, particularly in patients with a high risk of bleeding or those with valvular heart disease 3, 4.

Special Considerations

• Patients with bleeding problems may be considered for left atrial appendage occlusion devices instead of anticoagulation 3, 4.
• Patients with chronic kidney disease may require dose reduction of their anticoagulant therapy 3.
• Patients undergoing surgical procedures with high bleeding risk may need temporary anticoagulant discontinuation 3.
• Patients receiving anticoagulation who develop life-threatening bleeding should receive reversal therapy 3.

Stroke Risk Assessment

• The CHA2DS2-VASc score is a useful tool for assessing the risk of stroke in AF patients, with higher scores indicating a greater risk of stroke 3, 4, 5.
• Patients with a CHA2DS2-VASc score >4 have a higher risk of stroke and may benefit more from anticoagulation therapy 5.
• Patients with a CHA2DS2-VASc score <4 may have a lower risk of stroke and may not require anticoagulation therapy, or may be considered for aspirin therapy instead 5.