What is the recommended medication for stroke prevention in a 65-year-old patient with mild LVH and episodes of atrial fibrillation, Aspirin or Apixaban?

Apixaban is Strongly Recommended Over Aspirin for Stroke Prevention in This 65-Year-Old Patient with Atrial Fibrillation

For this 65-year-old patient with mild LVH, EF 55%, and documented episodes of atrial fibrillation lasting 3 days to 26 hours, apixaban is strongly recommended over aspirin for stroke prevention.

Risk Assessment and Rationale

This patient has several important risk factors for stroke:

• Age 65 years (1 point on CHA₂DS₂-VASc score)
• Left ventricular hypertrophy (indicates hypertension, 1 point)
• Multiple documented episodes of atrial fibrillation

CHADS₂ and CHA₂DS₂-VASc Score Analysis:

• The patient has a CHADS₂ score of at least 1 (age ≥65)
• The CHA₂DS₂-VASc score is at least 2 for a male or 3 for a female

According to current guidelines, this places the patient in a moderate to high-risk category for stroke, where oral anticoagulation is clearly indicated 1.

Evidence Supporting Apixaban Over Aspirin

1. Superior Stroke Prevention:

   • Apixaban reduced the risk of stroke or systemic embolism by 55% compared to aspirin in patients unsuitable for warfarin therapy 2
   • The 2016 ESC guidelines strongly recommend oral anticoagulants over antiplatelet therapy for patients with a CHA₂DS₂-VASc score of 2 or higher in males (Class I, Level A recommendation) 1

2. Comparable Bleeding Risk:

   • The AVERROES trial showed that apixaban had a similar bleeding risk profile compared to aspirin (4.5% vs 3.8% per year), despite providing significantly better stroke protection 3

3. Mortality Benefit:

   • Apixaban has been shown to reduce all-cause mortality by 11% compared to warfarin 2, while aspirin has not demonstrated this benefit

4. Current Guideline Recommendations:

   • The 2016 ESC guidelines explicitly state: "Antiplatelet monotherapy is not recommended for stroke prevention in AF patients, regardless of stroke risk" (Class III, Level A recommendation) 1
   • Guidelines recommend DOACs, including apixaban, as preferred over vitamin K antagonists (Class I, Level A) 1

Dosing Considerations

For this 65-year-old patient with normal renal function and no other specific risk factors mentioned:

• Standard dosing of apixaban 5 mg twice daily would be appropriate 4
• Dose reduction to 2.5 mg twice daily would only be necessary if the patient has at least two of:
  • Age ≥80 years
  • Body weight ≤60 kg
  • Serum creatinine ≥1.5 mg/dL 4

Important Considerations and Monitoring

1. Regular monitoring:

   • No routine coagulation monitoring is required for apixaban 5
   • Regular renal function assessment is essential 5

2. Perioperative management:

   • If surgery is needed, apixaban should be discontinued 48 hours before procedures with significant bleeding risk 4
   • For low bleeding risk procedures, discontinuation 24 hours prior is sufficient 4

3. Contraindications to consider:

   • Mechanical heart valves
   • Moderate-to-severe mitral stenosis
   • Severe renal failure
   • Active major bleeding 5

Conclusion

The evidence overwhelmingly supports using apixaban over aspirin in this patient. Current guidelines clearly state that antiplatelet monotherapy is not recommended for stroke prevention in atrial fibrillation patients, regardless of stroke risk 1. The documented episodes of atrial fibrillation lasting up to 3 days place this patient at significant stroke risk, and oral anticoagulation with apixaban offers superior protection with a manageable safety profile.