What is the recommended dual antiplatelet therapy (DAPT) regimen for patients with acute coronary syndrome (ACS) or those who have undergone coronary stent placement?

Recommended Dual Antiplatelet Therapy (DAPT) Regimen for ACS and Coronary Stent Placement

For patients with acute coronary syndrome (ACS) or those who have undergone coronary stent placement, ticagrelor (180 mg loading dose, 90 mg twice daily) on top of aspirin is recommended as the first-line DAPT regimen for 12 months, unless there are contraindications or excessive bleeding risk. 1

P2Y12 Inhibitor Selection Based on Clinical Scenario

Acute Coronary Syndrome (ACS)

• First choice: Ticagrelor (180 mg loading dose, 90 mg twice daily) plus aspirin, regardless of initial treatment strategy, including in patients pre-treated with clopidogrel (which should be discontinued when ticagrelor is commenced) 1
• Alternative for PCI patients: Prasugrel (60 mg loading dose, 10 mg daily) plus aspirin for P2Y12 inhibitor-naïve patients with NSTE-ACS or STEMI undergoing PCI, unless high bleeding risk or contraindications exist 1
• When ticagrelor/prasugrel contraindicated: Clopidogrel (600 mg loading dose, 75 mg daily) plus aspirin for patients with prior intracranial bleeding or indication for oral anticoagulation 1
• For STEMI with thrombolysis: Clopidogrel (300 mg loading dose in patients <75 years, 75 mg daily) plus aspirin 1

Stable Coronary Artery Disease with Stent Placement

• Clopidogrel (600 mg loading dose, 75 mg daily) plus aspirin is recommended 1

Important Contraindications and Precautions

Contraindications for Specific P2Y12 Inhibitors

• Ticagrelor: Previous intracranial hemorrhage or ongoing bleeds 1
• Prasugrel: Previous intracranial hemorrhage, previous ischemic stroke or TIA, ongoing bleeds; not recommended for patients ≥75 years or with body weight <60 kg 1, 2
• Prasugrel in NSTE-ACS: Not recommended when coronary anatomy is unknown 1
• Prasugrel in medically managed ACS: Not recommended 1

Measures to Minimize Bleeding Risk

• Use radial over femoral access for coronary angiography and PCI when performed by an expert radial operator 1
• Maintain a daily aspirin dose of 75-100 mg when used with DAPT 1
• Prescribe a proton pump inhibitor (PPI) in combination with DAPT 1
• Consider lower maintenance dose (5 mg) of prasugrel in patients weighing <60 kg 2

Duration of DAPT

For ACS Patients

• Standard duration: 12 months of DAPT with a P2Y12 inhibitor plus aspirin 1
• High bleeding risk: Consider shorter duration (6 months) if excessive bleeding risk exists (e.g., PRECISE-DAPT score ≥25) 1, 3
• Recent evidence: Short DAPT (≤3 months) followed by P2Y12 inhibitor monotherapy (particularly ticagrelor) may be considered in selected patients to reduce bleeding risk without increasing ischemic events 4

For Medically Managed ACS

• Continue P2Y12 inhibitor therapy (either ticagrelor or clopidogrel) for 12 months 1
• Ticagrelor is preferred over clopidogrel unless bleeding risk outweighs ischemic benefit 1

Special Considerations

Switching Between P2Y12 Inhibitors

• In ACS patients previously exposed to clopidogrel, switching to ticagrelor is recommended early after hospital admission (180 mg loading dose) regardless of timing and loading dose of clopidogrel, unless contraindications exist 1

Perioperative Management

• Continue aspirin perioperatively if bleeding risk allows 1
• Do not discontinue DAPT within the first month of treatment for elective non-cardiac surgery 1
• For urgent surgery that cannot be delayed, consider proceeding with continued DAPT 5
• For intracranial procedures or surgeries with fatal bleeding risk, consider cessation of P2Y12 inhibitor (with possible continuation of aspirin) 5
• Resume recommended antiplatelet therapy as soon as possible post-operatively 1

CYP2C19 Considerations for Clopidogrel

• Clopidogrel's effectiveness depends on its conversion to an active metabolite by CYP2C19 6
• Consider alternative P2Y12 inhibitors in patients identified as CYP2C19 poor metabolizers 6
• Avoid concomitant use of clopidogrel with omeprazole or esomeprazole; prefer pantoprazole or rabeprazole if PPI needed 1, 6

Common Pitfalls to Avoid

• Not switching from clopidogrel to ticagrelor in ACS patients when indicated 1
• Using prasugrel in NSTE-ACS patients before coronary anatomy is known 1
• Prescribing prasugrel to patients with history of stroke/TIA, age ≥75 years, or weight <60 kg 2
• Discontinuing DAPT prematurely, especially within first month after stent placement 1
• Using routine platelet function testing to adjust antiplatelet therapy 1
• Not prescribing a PPI with DAPT to reduce gastrointestinal bleeding risk 1