CHA₂DS₂-VASc and CHA₂DS₂-VA calculator
For health professionals
Stroke risk in non-valvular atrial fibrillation (AF). Australia’s 2018 AF guideline uses CHA₂DS₂-VA, which leaves out sex; the classic CHA₂DS₂-VASc is shown alongside.
For health professionals. A decision aid, not a decision. Not for AF with moderate to severe mitral stenosis or a mechanical heart valve, where anticoagulation is indicated regardless of score. Weigh bleeding risk and patient preference. Nothing you enter leaves this device.
How the score works
- Congestive heart failure or LV dysfunction: 1
- Hypertension: 1
- A₂ge 75 or over: 2
- Diabetes: 1
- S₂troke, TIA or thromboembolism: 2
- Vascular disease (prior MI, peripheral arterial disease, aortic plaque): 1
- Age 65 to 74: 1
- Sc, sex category (female): 1, in CHA₂DS₂-VASc only. Maximum 9 for VASc, 8 for VA.
Why Australia uses CHA₂DS₂-VA
- The 2018 National Heart Foundation of Australia and CSANZ AF guideline dropped female sex from the score. Female sex mainly adds risk when other risk factors are present, and including it complicated decisions without changing who benefits.
- Using CHA₂DS₂-VA gives one threshold for everyone: 0 = anticoagulation not recommended; 1 = may be considered; 2 or more = recommended.
- The 2024 European Society of Cardiology AF guideline also moved to CHA₂DS₂-VA, partly because sex-based scoring doesn’t fit people who are transgender, non-binary or on gender-affirming hormones.
- For most people, the CHA₂DS₂-VA score is the CHA₂DS₂-VASc score minus 1 for women.
Annual stroke rate by CHA₂DS₂-VASc score
- Score 00%
- Score 11.3%
- Score 22.2%
- Score 33.2%
- Score 44.0%
- Score 56.7%
- Score 69.8%
- Score 79.6%
- Score 86.7%
- Score 915.2%
Good to know
- Stroke risk changes with age and new conditions, so re-score at least yearly and after new diagnoses.
- Bleeding risk scores help identify modifiable risks (blood pressure, alcohol, interacting medicines) but shouldn’t on their own stop anticoagulation.
- Aspirin isn’t recommended for stroke prevention in AF.
- Check kidney function before choosing and dosing a NOAC. Our eGFR calculator can help, but many NOAC doses use creatinine clearance.
Common questions
What is the CHA2DS2-VASc score?
A stroke risk score for people with atrial fibrillation. It adds points for heart failure, high blood pressure, age, diabetes, previous stroke or TIA, vascular disease and female sex, from 0 to 9. Higher scores mean higher stroke risk.
What is the difference between CHA2DS2-VASc and CHA2DS2-VA?
CHA2DS2-VA is the same score without the point for female sex. Australia’s 2018 AF guideline and the 2024 European guideline use CHA2DS2-VA, so the same thresholds apply to everyone.
What CHA2DS2-VA score needs anticoagulation?
Under the Australian 2018 guideline, anticoagulation is recommended at a score of 2 or more, may be considered at 1, and isn’t recommended at 0. A non-vitamin K oral anticoagulant (NOAC) is preferred over warfarin for most people.
Is a CHA2DS2-VASc score of 1 in a woman high risk?
No. A woman whose only point is female sex has a CHA2DS2-VA score of 0, which is low risk, and anticoagulation isn’t recommended for that reason alone.
Does the score apply to all atrial fibrillation?
No. It isn’t used for AF with moderate to severe mitral stenosis or a mechanical heart valve, where anticoagulation (usually warfarin) is needed regardless of the score.
Sources
- Brieger D et al. National Heart Foundation of Australia and CSANZ: Australian clinical guidelines for the diagnosis and management of atrial fibrillation 2018. Heart Lung Circ 2018. CHA2DS2-VA; anticoagulation thresholds; NOACs preferred
- Heart Foundation: Atrial fibrillation guideline for health professionals. current Australian guideline
- MJA: New guidelines on atrial fibrillation and heart failure (2018). sexless CHA2DS2-VA; NOACs preferred
- January CT et al. 2014 AHA/ACC/HRS guideline for the management of patients with atrial fibrillation. adjusted stroke rate table
- Lip GY et al. Refining clinical risk stratification for predicting stroke in atrial fibrillation. Chest 2010. original CHA2DS2-VASc
- 2024 ESC guidelines for atrial fibrillation: moving the goalposts (Eur Cardiol Rev). ESC move to CHA2DS2-VA