CHA₂DS₂-VASc calculator
Stroke risk in non-valvular atrial fibrillation, with annual risk by score.
Scores 2 points.
Prior myocardial infarction, peripheral arterial disease or aortic plaque.
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This is a reference implementation of a published formula, provided for use by qualified healthcare professionals. It does not diagnose, does not account for the individual circumstances of any patient, and is not a recommendation for treatment. Confirm every result against your own institutional guidance before acting on it. Clinical judgement always takes precedence over a calculator.
About this calculation
CHA₂DS₂-VASc estimates annual stroke risk in non-valvular atrial fibrillation. It was designed to improve on CHADS₂ by better identifying genuinely low-risk patients, which is what it is most useful for.
Formula
C 1 · H 1 · A₂ (age ≥75) 2 · D 1 · S₂ (prior stroke/TIA) 2 · V 1 · A (age 65–74) 1 · Sc (female) 1
- Source
- Lip GYH et al., Chest — refining stroke risk stratification in atrial fibrillation (2010)
- Methodology version
- 1.0.0
- Last reviewed
- 2026-10-28
What this does not account for
- Validated for non-valvular atrial fibrillation. It does not apply to moderate or severe mitral stenosis or to a mechanical heart valve, where anticoagulation is indicated regardless of score.
- The annual risk percentages come from the derivation and validation cohorts and vary between published series. Treat them as approximate.
- Female sex is a risk modifier rather than an independent risk factor; several guidelines do not count it in the absence of any other factor.
- The score estimates stroke risk only. Bleeding risk is a separate assessment — see HAS-BLED — and the two are weighed together.