CHA₂DS₂-VA Score: The Current Standard for Stroke Risk Stratification in Atrial Fibrillation
The 2024 ESC guidelines now recommend the CHA₂DS₂-VA score (removing the sex category from CHA₂DS₂-VASc) as the primary tool for stroke risk stratification in non-valvular atrial fibrillation, with oral anticoagulation recommended for scores ≥2 and considered for scores of 1. 1
Score Components and Point Assignment
The CHA₂DS₂-VA score assigns points as follows:
- C (Congestive heart failure): 1 point for symptoms/signs of heart failure regardless of ejection fraction (including HFpEF, HFmrEF, HFrEF) or asymptomatic LVEF ≤40% 1
- H (Hypertension): 1 point for resting BP >140/90 mmHg on at least two occasions or current antihypertensive treatment 1
- A₂ (Age ≥75 years): 2 points 1
- D (Diabetes mellitus): 1 point 1
- S₂ (Prior Stroke/TIA/thromboembolism): 2 points 1
- V (Vascular disease): 1 point for prior MI, peripheral artery disease, or aortic plaque 1
- A (Age 65-74 years): 1 point 1
Maximum score: 9 points 2
Key Difference from CHA₂DS₂-VASc
The critical update in 2024 is the removal of the sex category (female = 1 point) from the original CHA₂DS₂-VASc score. 1 This change reflects evidence that female sex alone (without other risk factors) does not independently increase stroke risk sufficiently to warrant anticoagulation. 1, 2
Anticoagulation Decision Algorithm
Score = 0
Score = 1
- Anticoagulation should be considered (Class IIa recommendation) 1
- Requires shared decision-making balancing stroke risk against bleeding risk 1
- Approximately 15% of AF patients fall into this intermediate-risk category 1
Score ≥2
- Anticoagulation is recommended (Class I recommendation) 1
- Annual stroke risk increases progressively: Score 2 (2.2%), Score 3 (3.2%), Score 4 (4.0%), Score 5 (6.7%), Score 6 (9.8%) 2
- Direct oral anticoagulants (DOACs) preferred over warfarin 1
Clinical Application Pitfalls
Common scoring errors to avoid:
- Age miscalculation: Age 65-74 receives 1 point, age ≥75 receives 2 points (total of 2 points, not 3) 1, 2
- Hypertension definition: Both treated/controlled hypertension AND untreated hypertension count equally for 1 point 2
- Female sex no longer counted: Do not add a point for female sex in the CHA₂DS₂-VA score 1
- Vascular disease often missed: Must actively assess for prior MI, PAD, or aortic plaque 1
Special Populations
Atrial Flutter
- Treat identically to atrial fibrillation using the same CHA₂DS₂-VA scoring and anticoagulation thresholds 2
Hypertrophic Cardiomyopathy or Cardiac Amyloidosis
- Anticoagulation recommended regardless of CHA₂DS₂-VA score (Class I recommendation) 1
Device-Detected Subclinical AF
- DOAC therapy may be considered (Class IIb recommendation) in patients with elevated thromboembolic risk, excluding those at high bleeding risk 1
Antiplatelet Therapy
Antiplatelet drugs (aspirin alone or aspirin plus clopidogrel) are NOT recommended as an alternative to anticoagulation for stroke prevention in AF (Class III recommendation). 1
Reassessment Requirements
Periodic reassessment of thromboembolic risk is mandatory (Class I recommendation) to ensure anticoagulation is initiated when patients develop new risk factors that increase their CHA₂DS₂-VA score. 1
Comparison with American Guidelines
The 2024 AHA stroke prevention guidelines continue to reference CHA₂DS₂-VASc (with sex category included), recommending anticoagulation for annual stroke risk ≥2%, generally corresponding to CHA₂DS₂-VASc ≥2 in men or ≥3 in women. 1 However, the most recent 2024 ESC guidelines represent the current international consensus favoring CHA₂DS₂-VA. 1
Limitations
The CHA₂DS₂-VA score has modest predictive accuracy (C-statistic 0.6-0.7) and does not incorporate other potential risk factors such as impaired kidney function, cancer, rheumatoid arthritis, obesity, or smoking. 1 Clinicians should assess for additional thromboembolic risk factors beyond the score components. 1