💗 CHADS₂ Atrial Fibrillation Stroke Risk

When to use

Select each risk factor; the tool sums the points (0–6) and reports the annual stroke risk band.

How it works

CHADS₂ = congestive heart failure (1) + hypertension (1) + age ≥75 (1) + diabetes (1) + prior stroke/TIA (2). Annual stroke risk rises from ~1.9% at 0 to ~18.2% at 6.

Key points

• A score ≥2 generally favors oral anticoagulation, but contemporary guidelines prefer the finer CHA₂DS₂-VASc, especially at low scores (original synthesis · not guideline verbatim).
• Anticoagulation decisions should also weigh bleeding risk using HAS-BLED or ORBIT.
• CHADS₂ underestimates risk in some 'low-risk' patients that CHA₂DS₂-VASc reclassifies upward via sex, vascular disease, and age 65–74.

References

• Gage BF, et al. Validation of clinical classification schemes for predicting stroke (CHADS₂). JAMA. 2001.
• Joglar JA, et al. 2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Atrial Fibrillation. Circulation. 2024.

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