STEMI management algorithm

STEMI Recognition - Spotting the Tombstone

• ECG Criteria: New ST-segment elevation at the J-point in ≥2 contiguous leads.

  • ≥1 mm in most leads.
  • ≥2 mm in leads V2-V3 (men ≥40), ≥2.5 mm (men <40), ≥1.5 mm (women).

• Localization via ECG Leads:

Immediate Therapy - MONA's Swift Kick

• 📌 MONA guides initial therapy, but prioritize based on clinical need, not the acronym's order. Goal: ↓ myocardial O₂ demand & ↑ supply.
• Aspirin: Chew 162-325 mg immediately.
• Oxygen: Supplemental O₂ only if saturation < 90% or respiratory distress.
• Nitroglycerin: Sublingual 0.4 mg q5min for pain; reduces preload.
  • ⚠️ Contraindications: Hypotension (SBP < 90), RV infarct, recent PDE-5 inhibitor use.
• Morphine: For refractory chest pain despite nitrates.
• Beta-Blockers: Oral metoprolol within 24h if stable (no HF, shock).

⭐ Of the initial therapies, only Aspirin has been proven to reduce mortality in acute MI.

Reperfusion Strategy - The Clock is Ticking

Primary goal is to restore coronary blood flow. The choice between PCI and fibrinolysis is time-critical, guided by facility capability and transfer times.

• Percutaneous Coronary Intervention (PCI):

  • Preferred reperfusion strategy.
  • Goal: Door-to-balloon time < 90 minutes.

• Fibrinolysis (e.g., Alteplase, Tenecteplase):

  • Use if timely PCI is unavailable.
  • Goal: Door-to-needle time < 30 minutes.

⭐ If a patient is at a non-PCI capable hospital, the decision to transfer for PCI vs. giving fibrinolysis hinges on the expected First Medical Contact-to-device time. If this time is anticipated to be > 120 minutes, fibrinolysis is the correct immediate action.

• ⚠️ Key Absolute Contraindications to Fibrinolysis:
  • Any prior intracranial hemorrhage
  • Known structural cerebral vascular lesion
  • Ischemic stroke within 3 months
  • Suspected aortic dissection
  • Active bleeding or bleeding diathesis

Post-Reperfusion Care - Keep the Flow Going

• Dual Antiplatelet Therapy (DAPT): Lifelong Aspirin + P2Y12 inhibitor (e.g., Ticagrelor, Prasugrel) for at least 12 months.
• High-Intensity Statin: Atorvastatin 80 mg or Rosuvastatin 40 mg for all patients, regardless of baseline cholesterol.
• Beta-Blocker: Start within 24 hrs if no signs of HF/shock. Continue for ≥3 years (indefinite if LVEF <40%).
• ACE Inhibitor / ARB: Start within 24 hrs, especially with anterior MI, LVEF <40%, or heart failure.
• Aldosterone Antagonist: Add if LVEF ≤40% with HF symptoms or diabetes.
• 📌 Mnemonic: BASAA (Beta-blocker, Antiplatelet, Statin, ACEi, Aldosterone antagonist).

⭐ Prasugrel is contraindicated in patients with a prior history of stroke or TIA due to an increased risk of intracranial hemorrhage.

High‑Yield Points - ⚡ Biggest Takeaways

• Time is muscle: Rapid EKG diagnosis is paramount for initiating reperfusion.
• PCI is the gold standard: Aim for a door-to-balloon time of < 90 minutes.
• Use fibrinolysis if PCI is delayed > 120 minutes; door-to-needle goal is < 30 minutes.
• Immediate medications: Give chewed aspirin, a P2Y12 inhibitor, and anticoagulation.
• Post-reperfusion care: Continue Dual Antiplatelet Therapy (DAPT), a high-intensity statin, beta-blocker, and ACE inhibitor.
• Avoid nitrates in right-sided MI or with recent PDE-5 inhibitor use.