What is the recommended approach for anti-platelet therapy (Anti-Platelet Therapy) in patients at high risk of cardiovascular events?

Anti-Platelet Therapy for High-Risk Cardiovascular Patients

For patients at high risk of cardiovascular events, the recommended approach is single antiplatelet therapy with low-dose aspirin 75-100 mg daily or clopidogrel 75 mg daily for established coronary artery disease, with dual antiplatelet therapy (aspirin plus a P2Y12 inhibitor) reserved for the first 12 months after acute coronary syndromes or percutaneous coronary intervention. 1

Primary Prevention vs. Secondary Prevention

Primary Prevention (No Established Disease)

• For patients aged ≥50 years without symptomatic cardiovascular disease, low-dose aspirin 75-100 mg daily is suggested over no therapy, though the benefit is modest 1
• The reduction in myocardial infarction is closely balanced with increased major bleeding risk 1
• Aspirin should NOT be initiated before non-cardiac surgery to reduce perioperative cardiovascular events 1

Secondary Prevention (Established Disease)

• For patients with established coronary artery disease (defined as >1 year post-ACS, prior revascularization, coronary stenoses >50%, or evidence of cardiac ischemia), long-term single antiplatelet therapy is recommended 1
• Choose either aspirin 75-100 mg daily OR clopidogrel 75 mg daily as monotherapy 1
• Both agents reduce serious vascular events by approximately 25% in high-risk patients 1

Acute Coronary Syndromes Without PCI

For patients in the first year after ACS who have NOT undergone PCI:

• Dual antiplatelet therapy is mandatory: ticagrelor 90 mg twice daily plus low-dose aspirin 75-100 mg daily OR clopidogrel 75 mg daily plus low-dose aspirin 1
• Ticagrelor is preferred over clopidogrel when combined with aspirin 1
• This combination reduces cardiovascular death, non-fatal MI, or stroke by 20% compared to aspirin alone 1
• Major bleeding increases from 2.7% to 3.7% with dual therapy 1

Percutaneous Coronary Intervention with Stenting

Acute Coronary Syndrome with PCI

For the first 12 months after ACS with stent placement:

• Dual antiplatelet therapy with aspirin PLUS one of the following P2Y12 inhibitors 1:
  • Ticagrelor 90 mg twice daily (preferred) 1
  • Prasugrel 10 mg daily (avoid if prior stroke/TIA or age >75 years) 2
  • Clopidogrel 75 mg daily (if prasugrel or ticagrelor contraindicated) 1

Loading doses:

• Ticagrelor: 180 mg loading dose 1
• Prasugrel: 60 mg loading dose 1
• Clopidogrel: 600 mg loading dose 1

Elective PCI with Stenting

Minimum DAPT duration based on stent type 1:

• Bare-metal stents: aspirin 75-325 mg daily plus clopidogrel 75 mg daily for at least 1 month 1
• Drug-eluting stents: 3 months for -limus stents, 6 months for -taxel stents 1

After minimum duration through 12 months:

• Continue low-dose aspirin 75-100 mg plus clopidogrel 75 mg daily 1

After 12 months:

• Switch to single antiplatelet therapy (aspirin 75-100 mg daily OR clopidogrel 75 mg daily) 1

High Bleeding Risk Modifications

For patients with high bleeding risk (age ≥65 years, low BMI <18.5, diabetes, prior bleeding, or oral anticoagulants) 2:

• Shorten DAPT duration to 3-6 months after PCI 2, 3
• Consider 1-month DAPT in very high bleeding risk patients 3
• High bleeding risk is defined as ≥4% annual risk of serious bleeding or ≥1% risk of intracranial hemorrhage 2

Peripheral Artery Disease

For severe PAD with high ischemic risk features (previous amputation, chronic limb-threatening ischemia, prior revascularization, heart failure, diabetes, vascular disease in ≥2 beds, eGFR <60 mL/min/1.73 m²) 4:

• Dual pathway inhibition with rivaroxaban 2.5 mg twice daily plus aspirin 100 mg once daily is recommended to reduce MACE and major adverse limb events 4

For PAD without high ischemic risk:

• Single antiplatelet therapy with clopidogrel 75 mg daily or aspirin 75-160 mg daily 4

After lower extremity revascularization:

• Rivaroxaban 2.5 mg twice daily plus aspirin 100 mg once daily immediately post-procedure 4

Critical Pitfalls to Avoid

• NEVER continue long-term dual antiplatelet therapy (aspirin + clopidogrel) beyond 12 months in chronic stable CAD without recent revascularization—this increases bleeding without additional benefit 4
• NEVER use prasugrel in patients with prior stroke/TIA—cerebrovascular event rate increases from 1.2% to 6.5% 2
• NEVER use full-dose anticoagulation monotherapy for PAD without another indication (e.g., atrial fibrillation)—it increases bleeding without reducing MACE 4
• NEVER discontinue aspirin preoperatively when prescribed for secondary prevention except for procedures with high bleeding risk 1
• NEVER add triple antiplatelet therapy (aspirin + clopidogrel + cilostazol) routinely after stenting—no proven benefit 1

Aspirin Dosing Specifics

Maintenance dosing:

• 75-100 mg daily for long-term prevention in high-risk patients (≥3% annual cardiovascular risk) 1

Loading dosing:

• 160-300 mg loading dose when immediate antithrombotic effect is required (acute coronary syndromes, acute ischemic stroke) 1

No difference in outcomes between 81 mg and 325 mg daily in patients with established cardiovascular disease 1

Special Populations

Diabetes

• Aspirin 75-162 mg daily appears optimal 1
• No need for higher doses despite altered platelet function 1

Systolic LV Dysfunction Without CAD

• Do NOT use antiplatelet therapy or warfarin 1