CHA₂DS₂-VASc Score Calculator

CHA₂DS₂-VASc Calculator

Check all that apply. Score updates automatically.

C — Congestive heart failure / LV dysfunction +1

H — Hypertension +1

A₂ — Age ≥75 years +2

A — Age 65–74 years +1

D — Diabetes mellitus +1

S₂ — Prior stroke / TIA / thromboembolism +2

V — Vascular disease (prior MI, PAD, or aortic plaque) +1

Sc — Female sex +1

Low Risk

Annual Stroke Risk

No therapy

Recommendation

Scoring Components

C	Congestive heart failure or LV systolic dysfunction — 1 point
H	Hypertension (BP consistently >140/90 or on antihypertensive treatment) — 1 point
A₂	Age ≥75 years — 2 points (mutually exclusive with A below)
D	Diabetes mellitus (fasting glucose >125 mg/dL or on treatment) — 1 point
S₂	Prior stroke, TIA, or systemic thromboembolism — 2 points
V	Vascular disease (prior MI, peripheral arterial disease, or aortic plaque) — 1 point
A	Age 65–74 years — 1 point (mutually exclusive with A₂ above)
Sc	Female sex — 1 point (sex modifier, not independent risk factor per se)

Maximum score = 9. Age ≥75 (A₂) and Age 65–74 (A) are mutually exclusive — a patient can only score on one age category.

Annual Stroke Risk by Score

Score	Annual Stroke Risk	Risk Category	Recommendation
0	0%	Low	No antithrombotic therapy
1	1.3%	Low–Moderate	Males: Consider OAC. Females: No therapy (score = 1 due to sex alone = low risk)
2	2.2%	Moderate	OAC recommended (NOAC preferred)
3	3.2%	Moderate–High	OAC recommended
4	4.0%	High	OAC recommended
5	6.7%	High	OAC recommended
6	9.8%	High	OAC recommended
7	9.6%	High	OAC recommended
8	12.5%	High	OAC recommended
9	15.2%	Very High	OAC recommended

Data from Lip GYH et al. Chest 2010 (Euro Heart Survey cohort). OAC = oral anticoagulation.

ESC 2020 Guideline Recommendations

The ESC 2020 AF Guidelines use a "identify stroke risk, then assess bleeding risk" approach:

Step 1: Identify patients with truly low stroke risk (CHA₂DS₂-VASc = 0 in men, or 1 in women) — no antithrombotic therapy needed.
Step 2: In patients with ≥1 additional stroke risk factor (score ≥1 in men, ≥2 in women), offer OAC. Score 1 in males is a grey zone — shared decision making.
Step 3: Once decision to anticoagulate is made, assess bleeding risk using HAS-BLED to identify and correct modifiable bleeding risk factors — not to deny anticoagulation.
NOACs first: Apixaban, rivaroxaban, dabigatran, and edoxaban are all preferred over warfarin (VKA) in patients with non-valvular AF who are eligible for NOAC therapy (Class I, Level A).

Sex as a Risk Modifier

Female sex adds 1 point but is a risk modifier, not an independent stroke risk factor. Importantly:

A woman with a score of 1 (solely because of female sex) is classified as low risk — no anticoagulation needed.
A woman with a score of 2 (1 for female sex + ≥1 other risk factor) should be offered OAC.
A man with a score of 1 (one actual risk factor) is in the moderate range — consider anticoagulation based on individual assessment.
This asymmetry means women effectively need ≥2 non-sex risk factors to warrant OAC, while men need ≥1.

Available NOACs

Drug	Target	Dosing (standard AF)	Key Consideration
Apixaban	Factor Xa	5 mg BD (2.5 mg BD if ≥2 of: age ≥80, weight ≤60 kg, creatinine ≥133 µmol/L)	Lowest bleeding risk in ARISTOTLE; preferred in renal impairment
Rivaroxaban	Factor Xa	20 mg OD with evening meal (15 mg OD if CrCl 15–49 mL/min)	Once-daily dosing; ROCKET-AF trial
Dabigatran	Thrombin	150 mg BD (110 mg BD if age ≥80 or high bleeding risk)	Specific reversal agent (idarucizumab); avoid if CrCl <30
Edoxaban	Factor Xa	60 mg OD (30 mg OD if CrCl 15–50, weight ≤60 kg, or P-gp inhibitor)	ENGAGE AF-TIMI 48; requires initial parenteral anticoagulation

Interaction with HAS-BLED

CHA₂DS₂-VASc and HAS-BLED should always be assessed together. A high HAS-BLED score does not mean anticoagulation should be withheld — it means modifiable bleeding risk factors should be addressed. Most patients with high stroke risk also have high bleeding risk, and the net clinical benefit of anticoagulation still favours treatment in score ≥2.

References

Lip GYH, Nieuwlaat R, Pisters R, et al. Refining clinical risk stratification for predicting stroke and thromboembolism in atrial fibrillation using a novel risk factor-based approach. Chest. 2010;137(2):263–272.
Hindricks G, Potpara T, Dagres N, et al. 2020 ESC Guidelines for the diagnosis and management of atrial fibrillation. Eur Heart J. 2021;42(5):373–498.
Lip GYH. Implications of the CHA₂DS₂-VASc and HAS-BLED Scores for Thromboprophylaxis in Atrial Fibrillation. Am J Med. 2011;124(2):111–114.

CHA₂DS₂-VASc Score