CHA₂DS₂-VASc Score Calculation for Atrial Fibrillation Patient
The CHA₂DS₂-VASc score for this 64-year-old male patient with DM, HTN, CHF, and old stroke presenting with atrial fibrillation is 6 points.
Score Calculation Breakdown
Let's calculate the CHA₂DS₂-VASc score by assessing each component:
| Risk Factor | Points | Patient's Status |
|---|---|---|
| Congestive heart failure (CHF) | 1 | Present ✓ |
| Hypertension (HTN) | 1 | Present ✓ |
| Age ≥75 years | 2 | Not applicable (64 years old) |
| Diabetes mellitus (DM) | 1 | Present ✓ |
| Stroke/TIA/thromboembolism | 2 | Present (old stroke) ✓ |
| Vascular disease | 1 | Not mentioned in history |
| Age 65-74 years | 1 | Not applicable (64 years old) |
| Sex category (female) | 1 | Not applicable (male patient) |
Total score = 1 (CHF) + 1 (HTN) + 1 (DM) + 2 (previous stroke) + 1 (age 64 years) = 6 points
Clinical Implications
This CHA₂DS₂-VASc score of 6 indicates:
- Very high risk of thromboembolism with an adjusted annual stroke rate of approximately 9.8% without anticoagulation 1
- Oral anticoagulation therapy is strongly indicated for this patient
- The patient's risk is significantly elevated due to multiple comorbidities, particularly the history of stroke which alone contributes 2 points
Anticoagulation Recommendations
Based on this high CHA₂DS₂-VASc score:
- Oral anticoagulation is strongly recommended (Class I, Level A recommendation) 1
- Direct oral anticoagulants (DOACs) are preferred over warfarin unless contraindicated 2
- Regular monitoring of renal function and reassessment of bleeding risk is essential
Important Considerations
- The patient's score would be the same whether using the older CHADS₂ or the newer CHA₂DS₂-VASc scoring system
- Even with a single risk factor of previous stroke, anticoagulation would be indicated, but the multiple risk factors make the recommendation even stronger
- The presence of atrial fibrillation with these risk factors places the patient at particularly high risk for recurrent stroke
Common Pitfalls to Avoid
- Failing to count age 64 as a risk factor (this patient is 64, not 65, so does not get the point for age 65-74)
- Miscounting the points for stroke (worth 2 points, not 1)
- Overlooking the need for immediate anticoagulation given the high score
- Assuming that antiplatelet therapy alone would be sufficient (it is not recommended as monotherapy for stroke prevention in AF) 2