CHA₂DS₂-VASc
CHA₂DS₂-VASc estimates annual stroke risk in non-valvular atrial fibrillation to guide anticoagulation decisions. It scores: CHF (1), Hypertension (1), Age ≥75 (2), Diabetes (1), Stroke/TIA (2), Vascular disease (1), Age 65–74 (1), Sex female (1).
inputs
✓ when to use
Use in all patients with non-valvular atrial fibrillation (including paroxysmal, persistent, and permanent) to assess thromboembolic risk and guide anticoagulation decisions. Should be reassessed periodically as risk factors accumulate with age and comorbidities.
✗ when not to use
Not validated for valvular AF (mitral stenosis, mechanical heart valves) — these patients generally require anticoagulation regardless. The female sex point is a risk modifier, not an independent indication — a woman with no other risk factors (score 1 from sex alone) is not considered high risk. The score does not incorporate bleeding risk — always assess with HAS-BLED or similar alongside.
clinical pearls
- Female sex alone (score = 1) is NOT an indication for anticoagulation. The ESC explicitly states that the female sex category is a risk modifier — it elevates risk when other factors are present but does not indicate anticoagulation in isolation.
- ESC 2024 guidelines introduced CHA₂-VA (dropping sex and diabetes) as the primary assessment, recommending anticoagulation when CHA₂-VA ≥2 and considering it when CHA₂-VA = 1. Be aware of this evolving guidance.
- Always assess bleeding risk (HAS-BLED) alongside CHA₂DS₂-VASc. A high HAS-BLED score is not a contraindication to anticoagulation — it is an indicator to address modifiable bleeding risk factors and monitor more closely.
- DOACs (apixaban, rivarelbam, edoxaban, dabigatran) are preferred over warfarin in most patients with non-valvular AF. Warfarin remains indicated for mechanical valves and severe mitral stenosis.
- Reassess CHA₂DS₂-VASc at every clinical encounter. A patient who was score 0 at age 55 becomes score 1 at 65 and score 2 at 75 by age alone — anticoagulation decisions should evolve with the patient.