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ST‑Elevation Myocardial Infarction — Reperfusion Times, Antithrombotics, and Post‑PCI Care

System: Cardiology • Reviewed: Sep 1, 2025 • Step 1Step 2Step 3

Synopsis:

Activate the cath lab for PCI‑capable patients with goal first‑medical‑contact‑to‑device ≤90 min (≤120 min for transfers). If PCI unavailable in time, give fibrinolysis within 30 min of arrival if no contraindications and plan pharmaco‑invasive strategy. Load antiplatelets and anticoagulate; control pain and blood pressure; initiate secondary prevention.

Key Points

  • Use the highest‑yield diagnostic test early; do not let testing delay time‑critical therapy.
  • Set objective targets (hemodynamic, neurologic, respiratory) and reassess frequently.
  • Plan definitive source control or disease‑specific therapy when indicated; document follow‑up and patient education.

Algorithm

  1. Obtain ECG within 10 min; activate cath lab for PCI when eligible.
  2. Give aspirin load; select and load a P2Y12 inhibitor; start anticoagulant per PCI/lysis strategy.
  3. If PCI cannot be achieved within 120 min from FMC → give fibrinolysis within 30 min if no contraindications; arrange transfer for pharmaco‑invasive PCI.
  4. Treat complications: manage cardiogenic shock (consider MCS), arrhythmias, and heart failure.
  5. After reperfusion: initiate high‑intensity statin, β‑blocker, ACEi/ARB as indicated; plan cardiac rehab and risk‑factor control.

Clinical Synopsis & Reasoning

Activate the cath lab for PCI‑capable patients with goal first‑medical‑contact‑to‑device ≤90 min (≤120 min for transfers). If PCI unavailable in time, give fibrinolysis within 30 min of arrival if no contraindications and plan pharmaco‑invasive strategy. Load antiplatelets and anticoagulate; control pain and blood pressure; initiate secondary prevention.


Treatment Strategy & Disposition

Stabilize ABCs. Initiate guideline‑concordant first‑line therapy with precise dosing and continuous monitoring. Escalate to advanced/procedural interventions based on explicit failure criteria. Define ICU, step‑down, and ward disposition triggers; involve specialty teams early.


Epidemiology / Risk Factors

  • Risk varies by comorbidity and precipitants; see citations for condition‑specific data.

Investigations

TestRole / RationaleTypical FindingsNotes
12‑lead ECG (serial)DiagnosisST elevation in contiguous leads/new LBBBObtain within 10 minutes
Cardiac biomarkersAdjunctRise in troponin over timeDo not delay reperfusion
CXR (selective)Exclude differentialsAortic catastrophe signs, edemaDo not delay PCI

Pharmacology

Medication/InterventionMechanismOnsetRole in TherapyLimitations
Aspirin 325 mg chew (then 81 mg daily)Antiplatelet (COX‑1)MinutesAll patients unless allergy
P2Y12 inhibitor load (ticagrelor 180 mg or clopidogrel 600 mg)AntiplateletHoursPre‑/peri‑PCI or with lyticsChoice per bleeding risk/strategy
Anticoagulant (heparin 60 U/kg bolus, max 4000 U; or enoxaparin/fondaparinux per strategy)AnticoagulantImmediateProcedural anticoagulation/with lyticsMonitor ACT/anti‑Xa as applicable
Nitroglycerin IV/sublingualAnti‑ischemicMinutesRelieve ischemia/hypertensionAvoid with RV infarct or PDE‑5 use
Morphine (sparingly)AnalgesicMinutesPain controlMay delay absorption of P2Y12 inhibitors
Fibrinolytic (tenecteplase weight‑based)ThrombolyticImmediateIf PCI delay >120 min and no contraindicationsMonitor for ICH; give adjunct anticoagulation

Prognosis / Complications

  • Outcome depends on timeliness of diagnosis and definitive therapy; monitor for complications.

Patient Education / Counseling

  • Provide red‑flag education, adherence guidance, and explicit return precautions; arrange timely specialty follow‑up.

References

  1. ACC/AHA/SCAI Guideline for Coronary Artery Revascularization (STEMI pathways) — Link

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