CHADS₂-VASc Score

Stroke risk stratification in non-valvular atrial fibrillation. Estimates annual stroke risk to guide anticoagulation decisions.

Congestive Heart Failure / LV Dysfunction

CHF or LVEF ≤ 40%

Documented congestive heart failure or left ventricular dysfunction. +1 point

Hypertension

Hypertension (treated or untreated)

Blood pressure consistently > 140/90 mmHg on repeated measurements. +1 point

Age ≥ 75 years

Age 75 years or older

Advanced age is a major risk factor for thromboembolism. +2 points

Age 65–74 years

Age 65 to 74 years

Moderate age-related risk. +1 point

Diabetes Mellitus

Type 1 or Type 2 diabetes

Documented diabetes mellitus on treatment or with HbA1c ≥ 6.5%. +1 point

Prior Stroke / TIA / Thromboembolism

History of stroke, TIA, or systemic embolism

Previous cerebrovascular event or systemic thromboembolism. +2 points

Vascular Disease

Prior MI, PAD, or aortic plaque

Myocardial infarction, peripheral artery disease, or complex aortic plaque. +1 point

Female Sex

Female sex

Female gender alone does NOT warrant anticoagulation if age < 65 without other risk factors. +1 point

Select risk factors above and click Calculate to see results

Score 0 (male) or 1 (female): Low risk — no antithrombotic therapy or consider aspirin.
Score 1 (male) or 2 (female): Moderate risk — consider oral anticoagulation (shared decision-making).
Score ≥ 2: High risk — oral anticoagulation recommended (NOAC preferred over warfarin).
Female sex is NOT an independent risk factor for anticoagulation if it is the sole risk factor in patients < 65 years.
Use the HAS-BLED score alongside CHADS₂-VASc to assess bleeding risk.