What is the management algorithm for a patient with acute myocardial infarction (AMI) with no contraindications, such as active bleeding or severe kidney disease (Impaired Renal Function)?

Management Algorithm for Acute Myocardial Infarction

Initial Diagnosis and Assessment

Obtain a 12-lead ECG within 10 minutes of first medical contact and initiate continuous ECG monitoring with defibrillator capacity immediately. 1

• Record and interpret the ECG at the point of first medical contact, whether pre-hospital or in-hospital, with a maximum target delay of 10 minutes 1
• Look for ST-segment elevation in two contiguous leads, but also recognize STEMI equivalents including new bundle branch block, ventricular pacing, hyperacute T-waves, isolated ST-depression in anterior leads, or universal ST depression with ST-elevation in aVR 1
• Administer oxygen only if oxygen saturation is below 90%—routine oxygen administration is not recommended 1

Reperfusion Strategy Selection (Time Zero = STEMI Diagnosis)

Choose primary PCI if it can be performed within 120 minutes of STEMI diagnosis; otherwise, initiate fibrinolysis immediately (within 10 minutes). 1, 2

Primary PCI Pathway (If PCI Available ≤120 Minutes)

Antithrombotic therapy:

• Administer loading dose of aspirin (oral or IV if unable to swallow) immediately 1
• Give loading dose of prasugrel or ticagrelor (not clopidogrel) for primary PCI 1
• Administer unfractionated heparin as first-line anticoagulant (enoxaparin or bivalirudin are alternatives) 1

Logistics:

• Emergency medical services should bypass the emergency department and transport directly to the catheterization laboratory 1, 3, 4
• Alert the PCI center immediately after selecting the reperfusion strategy 1
• Transfer patients to 24/7 high-volume PCI centers regardless of whether primary treatment is PCI or fibrinolysis 1

Technical aspects:

• Use radial access as the standard approach 1
• Implant drug-eluting stents routinely 1
• Do not perform routine thrombus aspiration or deferred stenting—these are contraindicated 1

Fibrinolysis Pathway (If PCI Cannot Be Performed Within 120 Minutes)

Initiate fibrinolytic therapy within 10 minutes of STEMI diagnosis if the patient presents within 12 hours of symptom onset and has no contraindications. 2

Fibrinolytic agent and adjunctive medications:

• Use a fibrin-specific agent: tenecteplase, alteplase, or reteplase 2
• Administer aspirin loading dose (oral or IV) 2, 5
• Give clopidogrel loading dose immediately—this is the only P2Y12 inhibitor indicated with fibrinolysis (do not use prasugrel or ticagrelor initially) 2, 5, 6
• Administer enoxaparin as preferred anticoagulant: IV bolus followed by subcutaneous dosing (unfractionated heparin is an alternative) 2, 5

Post-fibrinolysis management:

• Transfer all patients to a PCI-capable center immediately after fibrinolysis 2, 5
• Perform routine angiography between 2-24 hours after successful fibrinolysis 2, 5
• Switch from clopidogrel to prasugrel or ticagrelor at the time of PCI 2, 5
• Perform rescue PCI immediately if fibrinolysis fails or if hemodynamic/electrical instability develops 5
• Perform emergency PCI for recurrent ischemia or evidence of reocclusion 5

Management of Non-Infarct Related Artery Lesions

Treat severe stenosis in non-infarct related arteries before hospital discharge, either during the index PCI or as a staged procedure. 1

• Evaluate severity by angiography or fractional flow reserve 1
• In cardiogenic shock, perform non-infarct related artery PCI during the index procedure 1

Post-Reperfusion Care

Monitor patients for at least 24 hours after reperfusion therapy. 1

• Pursue early ambulation and early discharge in uncomplicated patients 1
• Perform routine echocardiography during hospital stay to assess left and right ventricular function, detect mechanical complications, and exclude left ventricular thrombus 2

Maintenance Antithrombotic Therapy

Continue dual antiplatelet therapy with aspirin plus prasugrel or ticagrelor for 12 months after PCI. 1, 2, 5

• For patients initially treated with fibrinolysis and clopidogrel, switch to prasugrel or ticagrelor at the time of angiography/PCI 2, 5
• Continue anticoagulation until revascularization or for the duration of hospital stay up to 8 days in patients treated with fibrinolysis 5

Special Considerations for Cardiac Arrest

Perform primary PCI in patients with resuscitated cardiac arrest and ST-elevation on post-resuscitation ECG. 1

• In cases without ST-elevation but high suspicion of ongoing ischemia, perform urgent angiography within 2 hours after excluding non-coronary causes 1
• Initiate targeted temperature management early after resuscitation in patients who remain unresponsive 1
• Do not use pre-hospital cooling with rapid infusion of large volumes of cold IV fluid 1

Critical Pitfalls to Avoid

• Do not use prasugrel or ticagrelor as the initial P2Y12 inhibitor with fibrinolytic therapy—clopidogrel is specifically indicated in this setting, with transition to potent agents at the time of PCI 2, 5
• Do not delay transfer to a PCI-capable center after fibrinolysis—all patients require angiography regardless of apparent lysis success 2, 5
• Do not miss the 2-24 hour window for routine angiography after successful fibrinolysis—this timing is evidence-based and improves outcomes 2, 5
• Do not perform routine thrombus aspiration or deferred stenting during primary PCI—these strategies are contraindicated 1
• Do not use fondaparinux for primary PCI—this is contraindicated 2