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
- Obtain ECG within 10 min; activate cath lab for PCI when eligible.
- Give aspirin load; select and load a P2Y12 inhibitor; start anticoagulant per PCI/lysis strategy.
- If PCI cannot be achieved within 120 min from FMC → give fibrinolysis within 30 min if no contraindications; arrange transfer for pharmaco‑invasive PCI.
- Treat complications: manage cardiogenic shock (consider MCS), arrhythmias, and heart failure.
- 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
| Test | Role / Rationale | Typical Findings | Notes |
|---|---|---|---|
| 12‑lead ECG (serial) | Diagnosis | ST elevation in contiguous leads/new LBBB | Obtain within 10 minutes |
| Cardiac biomarkers | Adjunct | Rise in troponin over time | Do not delay reperfusion |
| CXR (selective) | Exclude differentials | Aortic catastrophe signs, edema | Do not delay PCI |
Pharmacology
| Medication/Intervention | Mechanism | Onset | Role in Therapy | Limitations |
|---|---|---|---|---|
| Aspirin 325 mg chew (then 81 mg daily) | Antiplatelet (COX‑1) | Minutes | All patients unless allergy | — |
| P2Y12 inhibitor load (ticagrelor 180 mg or clopidogrel 600 mg) | Antiplatelet | Hours | Pre‑/peri‑PCI or with lytics | Choice per bleeding risk/strategy |
| Anticoagulant (heparin 60 U/kg bolus, max 4000 U; or enoxaparin/fondaparinux per strategy) | Anticoagulant | Immediate | Procedural anticoagulation/with lytics | Monitor ACT/anti‑Xa as applicable |
| Nitroglycerin IV/sublingual | Anti‑ischemic | Minutes | Relieve ischemia/hypertension | Avoid with RV infarct or PDE‑5 use |
| Morphine (sparingly) | Analgesic | Minutes | Pain control | May delay absorption of P2Y12 inhibitors |
| Fibrinolytic (tenecteplase weight‑based) | Thrombolytic | Immediate | If PCI delay >120 min and no contraindications | Monitor 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
- ACC/AHA/SCAI Guideline for Coronary Artery Revascularization (STEMI pathways) — Link