What is the management approach for a patient presenting with ST-Elevation Myocardial Infarction (STEMI)?

Management of ST-Elevation Myocardial Infarction (STEMI)

Primary percutaneous coronary intervention (PCI) is the preferred reperfusion strategy for all STEMI patients when it can be performed within 120 minutes of diagnosis; if not possible, immediate fibrinolytic therapy should be administered within 12 hours of symptom onset. 1

Initial Diagnosis and Assessment

• Twelve-lead ECG recording and interpretation should be obtained as soon as possible at first medical contact, with a maximum target delay of 10 minutes 1
• ECG monitoring with defibrillator capacity should be initiated immediately in all patients with suspected STEMI 1
• Routine oxygen therapy is not recommended in patients with oxygen saturation ≥90% 1

Reperfusion Strategy

Primary PCI Strategy

• Primary PCI is the preferred reperfusion strategy when performed by an experienced team within 120 minutes of STEMI diagnosis 1
• Patients should be transferred directly to the catheterization laboratory, bypassing the emergency department 1
• PCI-capable centers should deliver 24/7 service and perform primary PCI without delay 1

Antithrombotic Therapy with Primary PCI

• Aspirin (oral 150-325 mg or IV 250-500 mg if unable to swallow) should be administered as soon as possible 1
• A potent P2Y12 inhibitor (prasugrel or ticagrelor, or clopidogrel if these are unavailable) should be administered before or at the time of PCI 1
• Prasugrel is contraindicated in patients with prior stroke/TIA, and generally not recommended in patients ≥75 years old (except high-risk patients with diabetes or prior MI) 2
• Anticoagulation during PCI should be provided with unfractionated heparin (UFH) as an IV bolus at 100 U/kg (60 U/kg if GPIIb/IIIa inhibitors are used) 1
• Fondaparinux is not recommended for primary PCI 1

Fibrinolytic Strategy (when primary PCI cannot be performed within 120 minutes)

• Fibrinolytic therapy should be initiated as soon as possible, preferably in the pre-hospital setting 1
• A fibrin-specific agent (tenecteplase, alteplase, or reteplase) is recommended 1
• Oral or IV aspirin should be administered 1
• Clopidogrel should be added to aspirin 1
• Anticoagulation should be administered until revascularization or for the duration of hospital stay (up to 8 days) 1:
  • Enoxaparin IV followed by subcutaneous (preferred over UFH) 1
  • Or UFH as a weight-adjusted IV bolus followed by infusion 1
• Transfer to a PCI-capable center should occur immediately after fibrinolysis 1

Post-Fibrinolysis Management

• Rescue PCI is indicated immediately when fibrinolysis has failed (<50% ST-segment resolution at 60-90 minutes) 1
• Emergency angiography and PCI are indicated in patients with heart failure/shock or if hemodynamic/electrical instability develops 1
• Angiography and PCI of the infarct-related artery should be performed between 2-24 hours after successful fibrinolysis 1

In-Hospital Management

• Routine echocardiography should be performed during hospitalization to assess LV and RV function, detect mechanical complications, and exclude LV thrombus 1
• Dual antiplatelet therapy (DAPT) with aspirin plus a P2Y12 inhibitor should be maintained for 12 months 1
• High-intensity statin therapy should be initiated as early as possible 1
• Beta-blockers should be started orally in patients with heart failure and/or LVEF <40% unless contraindicated 1
• IV beta-blockers must be avoided in patients with hypotension, acute heart failure, AV block, or severe bradycardia 1
• ACE inhibitors should be started within 24 hours in patients with heart failure, LV systolic dysfunction, diabetes, or anterior infarct 1

Post-Discharge Management

• Antiplatelet therapy with low-dose aspirin (75-100 mg) should be continued indefinitely 1
• DAPT should be continued for 12 months after PCI unless there are contraindications 1
• A proton pump inhibitor (PPI) should be used in combination with DAPT in patients at high risk of gastrointestinal bleeding 1
• LDL-C should be targeted to <1.8 mmol/L (70 mg/dL) or reduced by at least 50% if baseline is between 1.8-3.5 mmol/L 1
• Smoking cessation counseling with pharmacological support should be provided 1
• Participation in a cardiac rehabilitation program is strongly recommended 1

Special Considerations

• In patients with cardiogenic shock, emergency angiography and PCI are recommended 1
• Pre-hospital notification by paramedics can significantly reduce door-to-balloon times and improve outcomes 3
• Premature discontinuation of antiplatelet therapy increases the risk of stent thrombosis, MI, and death 2