CHA₂DS₂-VASc Stroke Risk
Assess stroke risk in atrial fibrillation and get an anticoagulation recommendation, with Nigeria-specific warfarin monitoring guidance.
CHA₂DS₂-VASc scores stroke risk in a patient with atrial fibrillation and translates that score directly into an anticoagulation recommendation. See How Calculator Tools Work for the shared layout.
Inputs
| Criterion | Points |
|---|---|
| Congestive heart failure | 1 |
| Hypertension | 1 |
| Age ≥ 75 | 2 |
| Age 65–74 | 1 |
| Diabetes | 1 |
| Prior stroke or TIA | 2 |
| Vascular disease | 1 |
| Female sex | 1 |
Score is out of 9.
Reading the result
Female sex alone doesn't drive the anticoagulation decision — the tool calculates an effective score that excludes the sex point when deciding on treatment, so a woman with no other risk factors isn't recommended anticoagulation on sex alone:
| Effective score | Recommendation |
|---|---|
| 0 | No anticoagulation needed |
| 1 | Consider anticoagulation — discuss risk/benefit with the patient, weigh against bleeding risk (HAS-BLED) |
| 2+ | Anticoagulation recommended |
Every result also shows the annual stroke risk associated with the raw score, from 0% (score 0) up to over 15% (score 9).
Every recommendation includes a Nigeria-specific note: warfarin is the most accessible oral anticoagulant locally, with INR monitoring every 4 weeks and a target range of 2.0–3.0.
Reference
Lip GY et al. Chest. 2010;137(2):263-272.