Do you recommend aspirin (acetylsalicylic acid) therapy for patients with asymptomatic coronary atherosclerosis?

Aspirin Therapy for Asymptomatic Coronary Atherosclerosis

Aspirin therapy is not recommended for patients with asymptomatic coronary atherosclerosis without other risk factors or evidence of clinically relevant atherosclerotic cardiovascular disease.

Evidence-Based Recommendation

The most recent guidelines from the European Society of Cardiology (2024) explicitly state that "it is not recommended to systematically treat patients with asymptomatic PAD without any sign of clinically relevant ASCVD with antiplatelet drugs" 1. This recommendation aligns with other evidence showing limited benefit of aspirin in purely asymptomatic disease.

Rationale for Not Recommending Routine Aspirin

1. Limited Evidence of Benefit:

   • Trials evaluating antiplatelet agents in asymptomatic patients with mild decrements in ABI failed to show benefit for MACE or revascularization 1
   • The benefits of aspirin in patients with asymptomatic peripheral artery disease are not well established (Class IIb, Level of Evidence: B) 1

2. Risk-Benefit Consideration:

   • Aspirin increases bleeding risk without providing sufficient cardiovascular benefit in purely asymptomatic patients
   • Even low-dose aspirin approximately doubles the risk of major extracranial bleeding 2

Special Circumstances Where Aspirin May Be Considered

Despite the general recommendation against routine use, aspirin may be considered in specific high-risk subgroups:

1. Asymptomatic Patients with Diabetes:

   • Aspirin (75-100 mg) for primary prevention may be considered in patients with asymptomatic PAD and diabetes mellitus, in the absence of contraindications (Class IIb) 1
   • Should only be considered when 10-year cardiovascular risk is sufficiently high (>5-10%) 2

2. Asymptomatic Carotid Stenosis:

   • In patients with asymptomatic >50% carotid stenosis, long-term antiplatelet therapy (commonly low-dose aspirin) should be considered if bleeding risk is low (Class IIa, Level C) 1

3. Coronary Artery Calcium Score:

   • CAC≥100 may identify subgroups where benefit exceeds harm for aspirin therapy 3
   • CAC=0 identifies subgroups where potential harm significantly exceeds benefit 3

Dosing Considerations

If aspirin is indicated for specific high-risk asymptomatic patients:

• The optimal dose is 75-100 mg daily 1, 2
• Higher doses (>100 mg) increase bleeding risk without providing additional cardiovascular benefit 4

Risk Assessment Algorithm

1. Assess for symptoms of coronary atherosclerosis:

   • If symptomatic → Aspirin therapy recommended (75-162 mg daily) 1
   • If asymptomatic → Continue evaluation

2. Evaluate for other forms of established ASCVD:

   • History of MI, stroke, TIA, peripheral artery disease
   • If present → Aspirin therapy recommended 1
   • If absent → Continue evaluation

3. Assess for high-risk features:

   • Diabetes mellitus
   • Significant carotid stenosis (>50%)
   • High coronary artery calcium score (≥100)
   • If present → Consider aspirin therapy (75-100 mg daily) 1, 2
   • If absent → Aspirin not recommended

4. Evaluate bleeding risk:

   • History of GI bleeding or peptic ulcer disease
   • Concurrent use of anticoagulants or NSAIDs
   • Uncontrolled hypertension
   • Advanced age (>70 years)
   • If high bleeding risk → Avoid aspirin even in high-risk patients 2

Clinical Pitfalls to Avoid

1. Automatic Prescription: Avoid prescribing aspirin to all patients with asymptomatic coronary atherosclerosis without risk stratification.

2. Overlooking Bleeding Risk: Always assess bleeding risk before initiating aspirin therapy, as even low-dose aspirin increases bleeding risk.

3. Using Inappropriate Doses: Higher doses (>100 mg) increase bleeding risk without providing additional cardiovascular benefit 4.

4. Neglecting Reassessment: Cardiovascular and bleeding risks change over time and require periodic reassessment 2.

5. Ignoring Other Risk Reduction Strategies: Focus on other proven risk reduction strategies (statins, blood pressure control, smoking cessation) for asymptomatic patients rather than relying on aspirin.