Clinical tool
CHA₂DS₂-VASc
Stroke risk in atrial fibrillation.
Score
0/ 9
Low risk
Anticoagulation generally not recommended at a score of 0 in men or 1 in women (where the single point is sex alone).
Female sex is a risk modifier rather than an independent risk factor — a woman scoring 1 on sex alone is treated as low risk, which is why the treatment thresholds differ by one point between men and women. The score applies to non-valvular AF; patients with moderate-to-severe mitral stenosis or a mechanical valve require anticoagulation regardless and must not be assessed with this tool. Bleeding risk is assessed separately, and a high bleeding score is a prompt to correct modifiable factors, not to withhold anticoagulation.
For practising medics only. Clinical tools support judgement, they do not replace it. Always verify results against current guidelines and the patient in front of you.