Stroke Risk Assessment and Anticoagulation Indication for a 66-Year-Old Man with Hypertension and Paroxysmal Atrial Fibrillation
The CHA₂DS₂-VASc score for this 66-year-old man with hypertension and paroxysmal atrial fibrillation is 2, and anticoagulation is indicated according to the 2023 ACC/AHA/ACCP/HRS atrial fibrillation guideline. 1
CHA₂DS₂-VASc Score Calculation
Let's calculate the patient's CHA₂DS₂-VASc score based on the information provided:
- C (Congestive heart failure): Not mentioned - 0 points
- H (Hypertension): Present - 1 point
- A₂ (Age ≥75 years): Not present - 0 points
- D (Diabetes): Not mentioned - 0 points
- S₂ (Prior Stroke/TIA): Not mentioned - 0 points
- V (Vascular disease): Not mentioned - 0 points
- A (Age 65-74 years): Present (66 years old) - 1 point
- Sc (Sex category female): Not present (male) - 0 points
Total CHA₂DS₂-VASc score = 2 points (1 point for hypertension + 1 point for age 65-74 years)
Anticoagulation Recommendation
According to the 2023 ACC/AHA/ACCP/HRS guideline for the diagnosis and management of atrial fibrillation, oral anticoagulation is recommended for patients with:
- CHA₂DS₂-VASc score ≥2 for men
- CHA₂DS₂-VASc score ≥3 for women 1
Since this patient is a male with a CHA₂DS₂-VASc score of 2, anticoagulation therapy is indicated.
This recommendation is also supported by the 2018 CHEST guideline, which states: "For patients with AF, including those with paroxysmal AF, stroke prevention should be offered to those AF patients with one or more non-sex CHA₂DS₂-VASc stroke risk factors (score of ≥1 in a male or ≥2 in a female)" 1.
Stroke Risk Assessment
The annual stroke risk for patients with a CHA₂DS₂-VASc score of 2 is approximately 2.2% per year without anticoagulation 1. This level of risk exceeds the threshold (generally considered to be 1-2% annual stroke risk) at which the benefits of anticoagulation outweigh the risks of bleeding in most patients 2.
Anticoagulation Options
For this patient with nonvalvular atrial fibrillation, the following options should be considered:
Direct Oral Anticoagulants (DOACs) are preferred over warfarin for eligible patients:
- Apixaban 5 mg twice daily
- Rivaroxaban 20 mg once daily with food
- Dabigatran 150 mg twice daily
- Edoxaban 60 mg once daily 3
Warfarin with a target INR of 2.0-3.0 is an alternative, particularly if the patient has a mechanical heart valve, moderate to severe mitral stenosis, or severe renal impairment 4.
Important Considerations
Pattern of AF: The recommendation for anticoagulation applies to all patterns of AF, including paroxysmal AF, as this patient has 1.
Age as a risk factor: For this patient, age (66 years) is a significant risk factor. Studies have shown that patients aged 65-74 years with AF have a higher stroke risk (approximately 3.50% per year) compared to other risk factors in the CHA₂DS₂-VASc score 2.
Bleeding risk assessment: Before initiating anticoagulation, bleeding risk should be assessed using tools such as the HAS-BLED score. However, high bleeding risk should not automatically contraindicate anticoagulation but rather indicate the need for closer monitoring and correction of modifiable bleeding risk factors 3.
Antiplatelet therapy alone: Monotherapy with antiplatelet agents (such as aspirin) is not recommended for stroke prevention in this patient, as it is significantly less effective than anticoagulation 3.
Follow-up and Monitoring
- Regular monitoring of compliance, side effects, and drug interactions is essential
- Renal function should be evaluated before initiating DOACs and at least annually
- Periodic reassessment of stroke and bleeding risk is recommended as risk factors may develop over time 3
In conclusion, this 66-year-old man with hypertension and paroxysmal atrial fibrillation has a CHA₂DS₂-VASc score of 2, which indicates a significant stroke risk that warrants anticoagulation therapy according to current guidelines.