What is the management approach for an acute STEMI?

Management of Acute ST-Elevation Myocardial Infarction (STEMI)

Primary percutaneous coronary intervention (PCI) is the recommended reperfusion strategy for all patients with STEMI presenting within 12 hours of symptom onset, with immediate transfer to a PCI-capable center that can perform the procedure without delay. 1

Initial Assessment and Management

Immediate Actions (First 10 Minutes)

• Obtain 12-lead ECG within 10 minutes of first medical contact 1
• Establish ECG monitoring with defibrillator capacity immediately 1
• Establish IV access
• Administer loading doses of antithrombotic therapy:
  • Aspirin 162-325 mg orally or IV (if unable to swallow) 1, 2
  • P2Y12 inhibitor loading dose: preferably prasugrel 60 mg or ticagrelor 180 mg (or clopidogrel 600 mg if these are unavailable) 1, 2, 3
  • Anticoagulation: Unfractionated heparin (UFH) as weight-adjusted IV bolus followed by infusion 1

Reperfusion Strategy Decision

• Primary PCI pathway (preferred if available within 120 minutes of first medical contact) 1, 2

  • Immediate transfer to catheterization laboratory, bypassing emergency department 1
  • Continue anticoagulation during procedure (UFH preferred for primary PCI) 1, 2
  • Avoid fondaparinux for primary PCI due to risk of catheter thrombosis 1

• Fibrinolytic therapy pathway (if primary PCI cannot be performed within 120 minutes) 1, 2

  • Administer fibrinolytic therapy within 12 hours of symptom onset 1
  • Prefer fibrin-specific agents (tenecteplase, alteplase, or reteplase) 1, 2
  • Add clopidogrel to aspirin 1
  • Provide anticoagulation until revascularization or hospital discharge (up to 8 days) 1
    • Enoxaparin IV followed by SC (preferred over UFH) 1
    • Or UFH as weight-adjusted IV bolus followed by infusion 1
  • Transfer to PCI-capable center immediately after fibrinolysis 1

Post-Reperfusion Management

Antithrombotic Therapy

• Continue dual antiplatelet therapy (DAPT):
  • Aspirin 75-100 mg daily indefinitely 1, 2
  • P2Y12 inhibitor (prasugrel, ticagrelor, or clopidogrel) for 12 months 1, 3
• Consider proton pump inhibitor for patients at high risk of gastrointestinal bleeding 1

Additional Pharmacotherapy

• Beta-blockers: Start within 24 hours in stable patients, especially with heart failure or LVEF <40% 1, 2
  • Avoid IV beta-blockers in patients with hypotension, acute heart failure, AV block, or severe bradycardia 1
• ACE inhibitors: Start within 24 hours in patients with heart failure, LV systolic dysfunction, diabetes, or anterior infarct 1, 2
• ARBs: Alternative to ACE inhibitors if intolerant, preferably valsartan 1, 2
• High-intensity statins: Start as early as possible with goal LDL-C <1.8 mmol/L (70 mg/dL) or ≥50% reduction 1, 2
• Mineralocorticoid receptor antagonists (MRAs): For patients with LVEF <40% and heart failure or diabetes 1

Monitoring and Imaging

• Monitor for at least 24 hours after reperfusion 2
• Perform routine echocardiography during hospital stay to assess:
  • LV and RV function
  • Mechanical complications
  • LV thrombus 1

Special Considerations

Cardiogenic Shock or Heart Failure

• Emergency angiography and PCI if indicated 1
• Consider mechanical circulatory support devices in selected cases

Failed Fibrinolysis

• Perform rescue PCI immediately if fibrinolysis fails (<50% ST-segment resolution at 60-90 min) 1
• Perform emergency angiography and PCI if hemodynamic/electrical instability or worsening ischemia 1

Successful Fibrinolysis

• Perform angiography and PCI of the infarct-related artery between 2-24 hours after successful fibrinolysis 1

Post-Discharge Management

Secondary Prevention

• Cardiac rehabilitation program participation 1
• Smoking cessation with appropriate support 1, 2
• Regular exercise (minimum 30 minutes daily) 2
• Continue medications:
  • DAPT for 12 months 1, 3
  • Beta-blockers, especially with reduced LVEF 1
  • ACE inhibitors/ARBs for patients with heart failure, reduced LVEF, diabetes, or anterior MI 1, 2
  • High-intensity statins 1, 2

Common Pitfalls to Avoid

• Delaying ECG beyond 10 minutes of first medical contact
• Administering routine oxygen to patients with SaO2 ≥90% 1
• Using fondaparinux for primary PCI 1
• Performing routine PCI of an occluded infarct-related artery >48 hours after symptom onset in asymptomatic patients 1
• Administering NSAIDs (except aspirin) during hospitalization 2
• Pre-hospital cooling using rapid infusion of large volumes of cold IV fluid after return of spontaneous circulation 1
• Failing to transfer patients to a PCI-capable center after fibrinolysis 1

By following this evidence-based approach to STEMI management, focusing on rapid reperfusion and appropriate adjunctive therapies, patient outcomes including mortality, morbidity, and quality of life can be significantly improved.