What medications are part of the Acute Coronary Syndrome (ACS) regimen?

Medications in the Acute Coronary Syndrome (ACS) Regimen

The core ACS medication regimen consists of dual antiplatelet therapy (aspirin plus a P2Y12 inhibitor), parenteral anticoagulation, high-intensity statin therapy, beta-blockers, and ACE inhibitors or ARBs, with additional therapies including nitrates for symptom relief and proton pump inhibitors for gastrointestinal protection in high-risk patients. 1

Antiplatelet Therapy

Aspirin

• Loading dose: 150-300 mg orally (or 75-250 mg IV if oral route not possible) 1
• Maintenance dose: 75-100 mg daily indefinitely 1
• When used with ticagrelor, the maintenance dose should be 81 mg daily 1
• Aspirin is recommended for all ACS patients unless contraindicated 2

P2Y12 Inhibitors (choose one)

Ticagrelor (preferred first-line):

• Loading dose: 180 mg orally 1
• Maintenance: 90 mg twice daily for 12 months 1
• Recommended for all moderate-to-high risk ACS patients regardless of management strategy 1
• Does not require metabolic activation and has more rapid onset than clopidogrel 3, 4

Prasugrel (for PCI patients):

• Loading dose: 60 mg orally 1
• Maintenance: 10 mg daily 1
• Reduce to 5 mg daily if age ≥75 years or body weight <60 kg 1
• Contraindicated in patients with prior stroke or TIA 1, 4
• Only use after coronary anatomy is known 1

Clopidogrel (alternative when ticagrelor/prasugrel contraindicated):

• Loading dose: 300-600 mg orally 1, 5
• Maintenance: 75 mg daily 1
• Less potent than newer P2Y12 inhibitors with slower onset 4
• Avoid with omeprazole or esomeprazole due to CYP2C19 interaction 6

Anticoagulation Therapy

Choose one based on management strategy:

For Medical Management (No PCI Planned)

Fondaparinux (preferred):

• 2.5 mg subcutaneously daily 1
• Best efficacy-safety profile for conservative management 7
• Contraindicated if CrCl <30 mL/min 1
• Do not use to support PCI due to catheter thrombosis risk 1

Enoxaparin (alternative):

• 1 mg/kg subcutaneously every 12 hours 1
• Reduce to 1 mg/kg daily if CrCl <30 mL/min 1
• If age ≥75 years with fibrinolytic therapy: no bolus, 0.75 mg/kg every 12 hours (max 75 mg for first 2 doses) 1

For PCI Support

Bivalirudin:

• 0.75 mg/kg IV bolus, then 1.75 mg/kg/hour during PCI 1
• Continue infusion 2-4 hours post-PCI for primary PCI 1
• Reduce infusion to 1 mg/kg/hour if CrCl <30 mL/min 1

Unfractionated Heparin (UFH):

• 70-100 U/kg IV bolus (target ACT 250-300 seconds) 1
• 50-70 U/kg if using GP IIb/IIIa inhibitor 1
• Adjust infusion to aPTT 60-80 seconds 1

Secondary Prevention and Long-Term Therapy

Statins

• High-intensity statin therapy should be initiated immediately 1, 7
• Start as early as possible and maintain long-term 1
• If goals not achieved with maximum tolerated statin dose, add ezetimibe 1
• For very high-risk patients not at goal with statin plus ezetimibe, add PCSK9 inhibitor 1

Beta-Blockers

• Initiate early in patients with ongoing ischemic symptoms 7
• Essential for both angina relief and reducing morbidity/mortality 1
• Contraindications include heart failure, hypotension, bradycardia, or heart block 7

ACE Inhibitors or ARBs

• Recommended for all ACS patients, especially with heart failure, hypertension, diabetes, or LV dysfunction post-MI 1, 8
• Use ARB if ACE inhibitor not tolerated (e.g., due to cough) 1, 8
• Monitor renal function and potassium levels when initiating 8

Nitrates

• Short-acting nitrates for immediate relief of angina 1
• Use for ongoing chest pain, uncontrolled hypertension, or heart failure signs 7
• Contraindicated with phosphodiesterase inhibitors or hypertrophic obstructive cardiomyopathy 1

Proton Pump Inhibitors

• Mandatory for patients with history of GI bleeding requiring triple antithrombotic therapy 1
• Reasonable for all patients on DAPT or triple therapy without prior GI bleeding 1
• Recommended for high-risk GI bleeding patients on aspirin monotherapy, DAPT, or oral anticoagulation 1

Duration of Dual Antiplatelet Therapy

• Standard duration: 12 months for all ACS patients 1, 7
• Shorter duration (3-6 months): Consider if high bleeding risk outweighs ischemic benefit 1
• Extended duration (>12 months): May be considered if bleeding risk is low, though optimal duration beyond 1 year not well established 4
• Minimize triple antithrombotic therapy duration (aspirin + P2Y12 inhibitor + oral anticoagulant) to limit bleeding risk 1

Special Considerations

Patients Requiring Oral Anticoagulation

• If atrial fibrillation present, use NOAC (apixaban 5 mg twice daily, dabigatran 150 mg twice daily, edoxaban 60 mg daily, or rivaroxaban 20 mg daily) over VKA 1
• Transition from triple therapy to dual therapy (oral anticoagulant plus clopidogrel) after acute phase 7
• Do not use ticagrelor or prasugrel as part of triple antithrombotic therapy 1

Renal Impairment

• Adjust anticoagulant and antiplatelet doses based on creatinine clearance 1, 7
• Fondaparinux contraindicated if CrCl <30 mL/min 1

Elderly Patients (≥75 years)

• Reduce prasugrel dose to 5 mg daily if used 1, 7
• Adjust antithrombotic dosing based on renal function and bleeding risk 7

Common Pitfalls to Avoid

• Do not discontinue anticoagulation prematurely before revascularization, as this causes rebound thrombin activity and increased reinfarction risk within 4-8 hours 1
• Avoid combining omeprazole or esomeprazole with clopidogrel due to significant reduction in antiplatelet activity 6
• Do not use prasugrel in patients with prior stroke/TIA or before coronary anatomy is known 1, 4
• Do not use fondaparinux to support PCI due to catheter thrombosis risk 1
• Monitor potassium closely when combining ACE inhibitors with mineralocorticoid receptor antagonists 8