CHA₂DS₂-VASc score for atrial fibrillation
Stroke risk in atrial fibrillation and whether to anticoagulate.
What CHA₂DS₂-VASc is for
It estimates the annual risk of stroke in non-valvular atrial fibrillation (and atrial flutter) and guides the decision to start an anticoagulant. Score it for every patient with AF, including paroxysmal AF.
The criteria
- Congestive heart failure or LV dysfunction: 1
- Hypertension (treated or not): 1
- Age 75 or over: 2
- Diabetes: 1
- Previous Stroke, TIA or thromboembolism: 2
- Vascular disease (previous MI, peripheral arterial disease, aortic plaque): 1
- Age 65–74: 1
- Sex category female: 1
Tick only one age box. The maximum score is 9.
Interpreting the score (NICE NG196)
- 2 or more: offer anticoagulation.
- 1 in a man: consider anticoagulation.
- 0 in a man, or 1 in a woman from sex alone: anticoagulation is not needed; reassess yearly or when risk factors change.
The 2024 European (ESC) guideline uses CHA₂DS₂-VA, which drops the point for female sex. Follow the guideline your hospital uses.
Worked example
A 68-year-old woman with hypertension and diabetes: age 65–74 (1) + female (1) + hypertension (1) + diabetes (1) = 4. Offer anticoagulation. A direct oral anticoagulant is usually preferred over warfarin if she can afford it and kidney function allows.
Limitations and pitfalls
- It does not apply to AF with moderate or severe mitral stenosis (often rheumatic, still common in Pakistan) or a mechanical heart valve. These patients need warfarin whatever the score; DOACs are not used.
- Aspirin alone is not recommended for stroke prevention in AF.
- Assess bleeding risk too (NICE suggests ORBIT; HAS-BLED is also widely used), and correct what you can: uncontrolled blood pressure, alcohol, NSAIDs, labile INR. A high bleeding score is a reason to fix risks and monitor closely, not by itself a reason to withhold anticoagulation.
- Check creatinine clearance before choosing and dosing a DOAC.
See atrial fibrillation, stroke, TIA, warfarin, apixaban, creatinine clearance calculator and the textbook chapter on anticoagulants and antiplatelets.
Frequently asked questions
What CHA2DS2-VASc score needs anticoagulation?
NICE advises offering anticoagulation at a score of 2 or more and considering it in men with a score of 1. A woman whose only point is her sex does not need it.
Does CHA2DS2-VASc apply to rheumatic mitral stenosis?
No. Moderate or severe mitral stenosis and mechanical valves carry a high stroke risk regardless of the score, and these patients need warfarin rather than a DOAC.
What is CHA2DS2-VA?
The version used in the 2024 European guideline, which removes the point for female sex. The other items are the same.
Should I give aspirin instead of an anticoagulant in AF?
No. Aspirin alone is not recommended for stroke prevention in AF; it gives little protection and still causes bleeding.
A calculator supports, but does not replace, clinical judgement. Check results before acting on them.