Cardiology
CHA₂DS₂-VASc score
CHA₂DS₂-VASc estimates yearly stroke risk in a person with non-valvular atrial fibrillation, and is the score anticoagulation decisions are written against. Age 75 or over and a prior stroke score two points; everything else scores one.
Enter the values
Result
0/ 9
Low
Anticoagulation is generally not recommended on stroke risk alone at this level.
- Estimated annual stroke risk
- 0.2%
- Sex category
- Male
This calculator is provided for reference and education. It does not replace clinical assessment, examination, current guidelines, local protocol, or professional judgment. Verify every result before acting on it. Nirogix accepts no liability for clinical decisions made using this tool.
The formula
- C — congestive heart failure: 1
- H — hypertension: 1
- A₂: age ≥ 75: 2
- D — diabetes: 1
- S₂: prior stroke, TIA or thromboembolism: 2
- V — vascular disease: 1
- A — age 65–74: 1
- Sc: female sex category: 1
Worked example
A 78-year-old woman with hypertension and diabetes: 2 + 1 + 1 + 1 = 5, a high-risk score
When to use it
- Deciding whether to anticoagulate in non-valvular atrial fibrillation
- Reviewing an existing anticoagulation decision
And when not to
- It does not apply to valvular atrial fibrillation or a mechanical valve, which are anticoagulated regardless.
- Female sex is a risk modifier rather than a risk factor: a woman with no other factors is low risk.
- A stroke risk score never stands alone. Pair it with a bleeding assessment and the patient’s own preference.
References
- Refining clinical risk stratification for stroke and thromboembolism in AF — Lip GYH et al., Chest, 2010
- Evaluation of risk stratification schemes for ischaemic stroke — Friberg L et al., European Heart Journal, 2012
Last reviewed 07/09/2026.
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These calculators are free and always will be. We also build Nirogix, a hospital management system for Indian clinics and hospitals. The same calculations are planned inside the consultation record, pre-filled from the chart.