Should atrial fibrillation with a CHA2DS2-VASc (Congestive heart failure, Hypertension, Age ≥ 75 years, Diabetes, Stroke or transient ischemic attack, Vascular disease, Age 65-74 years, Sex category) score of 0 be treated with anticoagulant therapy?

From the Guidelines

Anticoagulation therapy is not recommended for patients with atrial fibrillation who have a CHA2DS2-VASc score of 0, as the potential harms of anticoagulation outweigh the benefits in this low-risk population. These patients are considered to be at low risk for stroke, with an annual stroke risk of less than 1% 1. The 2024 ESC guidelines for the management of atrial fibrillation suggest that oral anticoagulants are recommended for all eligible patients, except those at low risk of incident stroke or thromboembolism (CHA2DS2-VA = 1 anticoagulation should be considered; CHA2DS2-VA ≥2 anticoagulation recommended) 1.

Some key points to consider in the management of these patients include:

• Monitoring regularly for any changes in their risk profile, as the development of additional risk factors would increase their CHA2DS2-VASc score and potentially warrant anticoagulation in the future 1
• Lifestyle modifications to manage other cardiovascular risk factors, including blood pressure control, diabetes management if applicable, smoking cessation, and maintaining a healthy weight 1
• Individualized decision-making, considering patient preferences and values alongside their clinical risk profile 1
• The use of the CHA2DS2-VASc score as a simple clinical-based stroke risk score to initially identify ‘low risk’ patients who should not be offered antithrombotic therapy to prevent stroke and reduce mortality 1

It's also important to note that this recommendation applies specifically to male patients with a score of 0, as female sex contributes one point to the CHA2DS2-VASc score 1. Overall, the decision to initiate anticoagulation should always be individualized, considering patient preferences and values alongside their clinical risk profile.

From the Research

Atrial Fibrillation Treatment with CHA2DS2-VASc Score of 0

• The CHA2DS2-VASc score is used to determine the risk of stroke in patients with atrial fibrillation and to guide anticoagulation therapy decisions 2, 3, 4, 5, 6.
• A score of 0 indicates a low risk of stroke, and anticoagulant therapy is not typically recommended for patients with a score of 0 3, 5.
• However, studies have shown that the risk of stroke can increase over time, even in patients with a low initial CHA2DS2-VASc score 2.
• One study found that the CHA2DS2-VASc score increased in approximately 12% of initially "low-risk" atrial fibrillation patients each year, and that initiation of warfarin once the score changed was associated with a better prognosis 2.
• Another study suggested that anticoagulation should be considered for atrial fibrillation patients with 1 additional risk factor of the CHA2DS2-VASc score (beyond sex) due to their high risk of ischemic stroke 6.

Considerations for Anticoagulation Therapy

• The decision to initiate anticoagulation therapy should be based on an individual patient's risk factors and stroke risk assessment 3, 4, 5.
• The HAS-BLED bleeding risk schema can be used to assess the risk of bleeding in patients with atrial fibrillation and to guide anticoagulation therapy decisions 3.
• Regular follow-up and reassessment of stroke risk is recommended for patients with atrial fibrillation, even those with a low initial CHA2DS2-VASc score 2.

Specific Recommendations

• Patients with a CHA2DS2-VASc score of 0 (males) or 1 (females) should not be offered antithrombotic therapy, according to some guidelines 5.
• However, other studies suggest that anticoagulation should be considered for atrial fibrillation patients with 1 additional risk factor of the CHA2DS2-VASc score (beyond sex) due to their high risk of ischemic stroke 6.
• The type of atrial fibrillation (paroxysmal or permanent) should not be considered in the thromboembolism risk stratification process 5.