Lesson Objectives:
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Differentiate between STEMI, NSTEMI, and unstable angina.
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Understand the initial assessment and emergency management of ACS.
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Review reperfusion strategies, including thrombolysis, PCI, and CABG.
Recognizing ACS: STEMI vs. NSTEMI vs. Unstable Angina
ACS is classified based on ECG findings and cardiac biomarkers (troponins):
| Type | ECG Changes | Troponin Elevation | Pathophysiology |
|---|---|---|---|
| STEMI | ST elevation ≥1 mm in ≥2 contiguous leads | Elevated | Complete coronary occlusion (plaque rupture + thrombosis) |
| NSTEMI | ST depression, T-wave inversion | Elevated | Partial coronary occlusion |
| Unstable Angina | Normal or nonspecific changes | Normal | Partial occlusion with no myocardial necrosis |
Initial ACS Management – “MONA BASH” Mnemonic
🚑 Immediate interventions (Pre-hospital & ED care):
🔹 M – Morphine (for persistent pain, if not hypotensive).
🔹 O – Oxygen (if SpO₂ <90%).
🔹 N – Nitroglycerin (caution in RV infarct or hypotension).
🔹 A – Aspirin 325 mg (chewed, immediately).
🔹 B – Beta-blockers (unless contraindicated by bradycardia or heart failure).
🔹 A – ACE inhibitors (for long-term remodeling).
🔹 S – Statins (high-intensity for LDL control).
🔹 H – Heparin (LMWH or UFH for anticoagulation).
Reperfusion Therapy: PCI vs. Thrombolysis vs. CABG
🚨 Primary PCI (Percutaneous Coronary Intervention)
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Gold standard for STEMI (door-to-balloon time <90 min).
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Performed via angioplasty + stent placement.
🚨 Thrombolysis (if PCI unavailable within 120 min)
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Indications: STEMI with PCI delay.
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Agents: tPA (alteplase), tenecteplase.
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Contraindications: Stroke history, active bleeding, recent major surgery.
🚨 CABG (Coronary Artery Bypass Graft) Surgery
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Indications: Left main disease, multivessel CAD, failed PCI.
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Uses grafts from internal mammary artery or saphenous vein.
Post-ACS Management & Secondary Prevention
✔️ DAPT (Dual Antiplatelet Therapy): Aspirin + P2Y12 inhibitor (clopidogrel, ticagrelor).
✔️ Lipid control: High-dose statins (atorvastatin 80 mg, rosuvastatin 40 mg).
✔️ BP & Diabetes Management: ACE inhibitors, beta-blockers.
✔️ Lifestyle changes: Smoking cessation, exercise, Mediterranean diet.