Crushing central chest pain
A 58-year-old smoker with hypertension has 40 minutes of central crushing chest pain radiating to the left arm, with sweating and nausea. ECG shows 3 mm ST elevation in leads II, III and aVF.
Questions & answers
Q1 Which territory and vessel are involved?
Inferior wall, supplied by the right coronary artery in about 85% of people and by a dominant left circumflex in the remainder. Reciprocal ST depression in I and aVL supports the diagnosis.
Q2 Why must you record right-sided leads?
To detect right ventricular infarction (ST elevation in V4R), which occurs in up to a third of inferior infarcts. These patients are preload-dependent: nitrates and opioids can precipitate profound hypotension, and treatment is cautious fluid loading instead.
Q3 What is the reperfusion strategy?
Primary PCI is the treatment of choice if it can be delivered within 120 minutes of first medical contact; otherwise fibrinolysis followed by transfer for angiography within 2–24 hours. Give aspirin 300 mg plus a P2Y12 inhibitor and an anticoagulant, with oxygen only if hypoxaemic.
Q4 Which complications follow inferior infarction?
Bradyarrhythmias and AV block from AV nodal artery involvement, right ventricular failure, papillary muscle rupture with acute mitral regurgitation, ventricular arrhythmias, pericarditis and, late, ventricular aneurysm.
References
- ESC 2023 Guidelines for the management of acute coronary syndromes.
- Fourth universal definition of myocardial infarction, 2018.