Dual Antiplatelet Therapy for Acute Coronary Syndrome

Introduction to Dual Antiplatelet Therapy

• The American College of Cardiology recommends initiating aspirin (75-100 mg daily) plus either ticagrelor (180 mg loading dose, then 90 mg twice daily) or prasugrel (60 mg loading dose, then 10 mg daily) for at least 12 months in patients with acute coronary syndrome undergoing PCI with stent placement, with ticagrelor or prasugrel strongly preferred over clopidogrel 1, 2

P2Y12 Inhibitor Selection

• The American Heart Association suggests that first-line therapy is ticagrelor or prasugrel, not clopidogrel, for patients with acute coronary syndrome 1, 2, 3
• Ticagrelor is the preferred first-line P2Y12 inhibitor for all ACS patients regardless of initial treatment strategy, including those pre-treated with clopidogrel (which should be discontinued when ticagrelor is started) 3

Standard Duration: 12 Months

• The default DAPT duration is 12 months for all ACS patients who are not at high bleeding risk, regardless of type of ACS, type of stent used, or whether complete revascularization was achieved 1, 2, 4

Bleeding Risk Mitigation Strategies

• The American College of Cardiology recommends prescribing a proton pump inhibitor (PPI) with DAPT in all patients to reduce gastrointestinal bleeding 1, 3
• The American College of Cardiology suggests using radial artery access over femoral access for PCI when performed by an experienced radial operator 1, 3

De-escalation Options After Initial Period

• For patients who have tolerated DAPT with ticagrelor, transition to ticagrelor monotherapy (discontinue aspirin) ≥1 month after PCI 1, 2
• For patients requiring long-term anticoagulation, discontinue aspirin 1-4 weeks after PCI and continue P2Y12 inhibitor (preferably clopidogrel, not ticagrelor) 1, 3

Special Clinical Scenarios

• For patients with NSTE-ACS scheduled for invasive strategy with angiography >24 hours away, upstream treatment with clopidogrel or ticagrelor may be considered to reduce MACE 1, 2

Critical Pitfalls to Avoid

• Do not discontinue DAPT prematurely, especially within the first month after stent placement, as this dramatically increases risk of stent thrombosis, MI, and death 1, 3
• Do not fail to prescribe a PPI with DAPT - this is a simple intervention that significantly reduces GI bleeding 1, 3
• Do not use clopidogrel as first-line therapy when ticagrelor or prasugrel are available and not contraindicated 1, 2

Perioperative Management

• Continue aspirin perioperatively if bleeding risk allows 3
• Do not discontinue DAPT within the first month for elective non-cardiac surgery 3
• Resume antiplatelet therapy as soon as possible post-operatively 3