Acute Treatment of Non-ST-Elevation Myocardial Infarction
Start dual antiplatelet therapy immediately with aspirin plus ticagrelor or prasugrel (not clopidogrel unless contraindicated), initiate anticoagulation with heparin or enoxaparin, and proceed with early invasive coronary angiography with intent for complete revascularization via PCI using radial access. 1
Immediate Antiplatelet Therapy
Load with aspirin (loading dose followed by 75-100 mg daily maintenance) combined with a potent P2Y12 inhibitor 1, 2:
- Ticagrelor: 180 mg loading dose, then 90 mg twice daily (preferred option)
- Prasugrel: 60 mg loading dose, then 10 mg daily (avoid if prior stroke/TIA or age >75 with low body weight)
- Clopidogrel: 600 mg loading dose, then 75 mg daily (only if ticagrelor/prasugrel contraindicated or not tolerated) 2
The 2025 ACC/AHA guidelines explicitly state that ticagrelor or prasugrel should be preferred over clopidogrel in NSTE-ACS patients undergoing PCI due to superior outcomes in the PLATO and TRITON-TIMI 38 trials 1. Clopidogrel's weaker and more variable platelet inhibition makes it a second-line choice 2.
Continue dual antiplatelet therapy for at least 12 months as the default strategy 1.
Anticoagulation Strategy
Initiate anticoagulation immediately upon diagnosis 3:
- Enoxaparin: 0.5 mg/kg IV bolus (or 1 mg/kg subcutaneously twice daily)
- Unfractionated heparin: 70-100 U/kg IV bolus (50-70 U/kg if using GP IIb/IIIa inhibitors)
- Bivalirudin: 0.75 mg/kg IV bolus followed by 1.75 mg/kg/h infusion 2
Continue anticoagulation through the hospitalization period until PCI is performed 3.
Invasive Management Approach
Proceed with early coronary angiography with intent for revascularization 1:
- Use radial artery access over femoral approach—this reduces bleeding, vascular complications, and mortality 1
- Pursue complete revascularization of all significant stenoses, not just the culprit lesion 1
- Use intracoronary imaging (IVUS or OCT) to guide PCI in complex lesions 1
- Multivessel PCI can be performed in a single procedure or staged, with preference toward single-procedure completion 1
The choice between PCI versus CABG for multivessel disease should be based on coronary anatomy complexity and comorbidities 1.
Critical Caveats and Pitfalls
Bleeding risk management is essential 1:
- Add a proton pump inhibitor for patients at gastrointestinal bleeding risk
- In patients tolerating ticagrelor well, transition to ticagrelor monotherapy ≥1 month after PCI to reduce bleeding
- For patients requiring long-term anticoagulation (e.g., atrial fibrillation), discontinue aspirin 1-4 weeks post-PCI and continue P2Y12 inhibitor (preferably clopidogrel) with the anticoagulant 3
Cardiogenic shock exception: If present, perform emergency revascularization of the culprit vessel only—do NOT routinely treat non-infarct arteries at the same time 1. Consider microaxial flow pump support in selected cases, though this increases bleeding and limb ischemia risk 1.
Anemia management: Red blood cell transfusion to maintain hemoglobin of 10 g/dL may be reasonable in patients with acute or chronic anemia who are not actively bleeding 1.
Post-Discharge Essentials
- Refer to cardiac rehabilitation (including home-based options) 1
- Check fasting lipid panel 4-8 weeks after initiating or adjusting lipid-lowering therapy 1
- Aggressive risk factor modification for secondary prevention 1
Do not use thrombolysis in NSTEMI—despite recent meta-analyses suggesting potential benefit in select non-ST-elevation presentations 4, current guidelines contraindicate fibrinolytic therapy in NSTE-ACS due to lack of proven benefit and increased bleeding risk 2.