Acute coronary occlusion producing transmural ischaemia with ST elevation on ECG.
Causes
- • Plaque rupture with occlusive thrombus
- • Coronary spasm/embolism
- • Spontaneous coronary artery dissection (SCAD)
Risk factors
- • Age, male, smoking, HTN, DM, dyslipidaemia, family history, CKD, obesity
Clinical features
- • Central crushing chest pain >20 min
- • Diaphoresis, dyspnoea, nausea
- • Radiation to arm/jaw
Examination
- • Anxious, cool clammy
- • Tachy/brady
- • S4 gallop
- • Signs of HF
Investigations
- • 12-lead ECG within 10 min
- • hs-troponin serial
- • CBC, U&E, glucose, lipid, coag
- • Portable CXR, echo
Diagnosis
- • ECG ST↑ ≥1 mm in ≥2 contiguous limb leads OR ≥2 mm V2-V3 (M) / ≥1.5 mm V2-V3 (F)
- • New LBBB with symptoms
- • Posterior MI = ST↓ V1-V3 with dominant R
Differential diagnosis
- • Aortic dissection
- • PE
- • Pericarditis/myocarditis
- • Oesophageal spasm/rupture
- • Pneumothorax
Management
- • Aspirin 300 mg + P2Y12 (ticagrelor 180 mg / prasugrel 60 mg)
- • Anticoag: heparin 60 U/kg or bivalirudin
- • Primary PCI ≤120 min (door-to-balloon ≤90 min)
- • Fibrinolysis if PCI unavailable ≤12 h (contraindication check)
Drug therapy
- • High-intensity statin (atorvastatin 80 mg)
- • β-blocker if no HF/shock
- • ACEi/ARB within 24 h if EF<40 or DM
- • MRA if EF≤40 + HF/DM
- • Long-term DAPT 12 months
Complications
- • Arrhythmia (VF/VT, AV block)
- • HF, cardiogenic shock
- • Papillary muscle/VSR rupture
- • LV thrombus/embolism
- • Dressler syndrome
Prevention
- • Smoking cessation
- • Mediterranean diet
- • Exercise (cardiac rehab)
- • Lipid + BP control
Follow-up
- • Cardiac rehab at 4-6 weeks
- • Echo at 6 weeks (LVEF)
- • Lipid + HbA1c 3 months
Clinical pearls
- • Time = muscle — activate cath lab bypass ED
- • Right-sided leads in inferior MI (V4R)
- • Sgarbossa criteria in LBBB
References
- • ESC 2023 STEMI Guidelines
- • AHA/ACC 2022 Chest Pain Guideline
Related in WardRound
Educational — verify locally.
