Anticoagulation Therapy for Atrial Fibrillation Based on CHA2DS2-VASc Score

Risk Assessment and Recommendations

• The American College of Cardiology recommends direct oral anticoagulants (DOACs) over warfarin for stroke prevention in patients with atrial fibrillation who have a CHA2DS2-VASc score ≥1 in men or ≥2 in women, except in those with moderate to severe mitral stenosis or mechanical heart valves 1, 2, 3
• The CHA2DS2-VASc score is the recommended tool for stroke risk assessment in patients with AF, with components including congestive heart failure, hypertension, age, diabetes mellitus, prior stroke, vascular disease, and sex category 4, 1, 5
• The American Heart Association and American College of Cardiology recommend that patients with a CHA2DS2-VASc score of 0 in men or 1 in women (due to female sex alone) do not require anticoagulation therapy 6, 4
• For patients with a CHA2DS2-VASc score ≥1 in men or ≥2 in women, oral anticoagulation therapy is recommended, with DOACs preferred over warfarin 1, 2, 6

Choice of Anticoagulant and Monitoring

• The American College of Cardiology recommends DOACs (dabigatran, rivaroxaban, apixaban, edoxaban) as first-line therapy over warfarin for stroke prevention in AF, due to their non-inferiority and potential superiority with lower risks of serious bleeding 1, 2, 3
• For patients on warfarin, the International Normalized Ratio (INR) should be checked at least weekly during initiation and monthly when stable in therapeutic range (target INR 2.0-3.0 for AF) 1
• Bleeding risk assessment should be performed at every patient contact using the HAS-BLED score, with high scores warranting more frequent follow-up and addressing modifiable bleeding risk factors 6, 7, 8

Patient Evaluation and Decision Making

• The American College of Cardiology recommends that anticoagulation decisions involve discussion of absolute risks of stroke and bleeding, patient preferences and values, medication adherence considerations, and cost and monitoring requirements 1, 2, 3
• Reevaluation of stroke and bleeding risks should occur periodically, as these risks are dynamic 1, 6
• Antiplatelet therapy alone is not recommended for stroke prevention in AF, regardless of CHA2DS2-VASc score 6, 8