Chest pain with a misleading initial ECG in a young smoker
A 34-year-old man with a 15 pack-year smoking history and no prior cardiac history presents at 02:00 with 90 minutes of central crushing chest pain radiating to the left jaw, associated with sweating and nausea. He took a sildenafil 50 mg tablet approximately 3 hours ago. Vital signs: BP 148/92 mmHg, HR 102/min, SpO2 97% on room air, afebrile. Initial 12-lead ECG shows 1 mm ST elevation in III and aVF with reciprocal depression in aVL, and the pain has eased from 8/10 to 4/10 since arrival. Troponin is pending. The nearest catheterisation laboratory is 90 minutes away by road; the local hospital has no on-site PCI but does have a coronary care unit and thrombolysis capability.
1. How would you risk-stratify and disposition this patient right now?
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This is an inferior STEMI pattern (ST elevation in III/aVF with reciprocal aVL depression) in a patient with a heavy smoking history, so I treat it as an acute coronary syndrome with persistent ST elevation until proven otherwise - the partial pain resolution does not downgrade it.
Key confounders to address explicitly:
- Sildenafil within 24 hours is a relative contraindication to nitrate therapy (risk of profound hypotension). I would not give sublingual or IV nitrates. If pain persists and I consider nitrates at all, it must be with extreme caution and continuous monitoring - in practice I avoid them.
- Reperfusion strategy: symptom onset ~90 minutes, PCI centre 90 minutes away. First medical contact-to-device would exceed 120 minutes, so fibrinolysis is the preferred strategy if there are no contraindications (no recent stroke, no bleeding, no severe hypertension - BP 148/92 is acceptable). I would give a fibrin-specific agent (e.g. tenecteplase weight-adjusted) plus aspirin, clopidogrel, and anticoagulation, and arrange immediate transfer to the PCI centre for rescue/routine angiography.
- If fibrinolysis is contraindicated or fails (persistent pain, <50% ST resolution at 60–90 min, or haemodynamic instability), proceed to rescue PCI.
- Differential to keep open: pulmonary embolism (smoker, tachycardia), aortic dissection (though radiation to jaw and ECG changes favour ACS), and pericarditis. A bedside echo and CXR do not delay reperfusion.
Disposition: CCU, continuous monitoring, IV access, defibrillator at bedside, serial ECGs and troponins, and activate the transfer pathway now rather than after the troponin result.
2. The troponin returns at 0.9 ng/mL (upper limit 0.04). The patient is now pain-free with 0.5 mm residual ST elevation in III. What does the troponin add, and how does it change management?
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The troponin confirms myocardial necrosis but does not change the reperfusion decision - the diagnosis of STEMI is ECG-based, and reperfusion must not wait for biomarkers. A positive troponin in this context supports the diagnosis and carries prognostic weight (larger infarct, higher risk of heart failure and arrhythmia) but is not a gate to thrombolysis or transfer.
What it does change:
- Risk stratification: elevated troponin with inferior STEMI warrants closer monitoring for mechanical complications (papillary muscle rupture, VSD), right ventricular involvement, and arrhythmia.
- Right ventricular infarction: I would obtain right-sided leads (V4R) and check for hypotension with nitrates - reinforcing the decision to avoid nitrates.
- Antiplatelet/anticoagulant intensification per ACS pathway, and consideration of early invasive angiography even if fibrinolysis is given (routine early transfer).
- Echocardiography to assess LV and RV function and screen for pericardial effusion.
The residual 0.5 mm ST elevation with a pain-free patient is consistent with reperfusion; I would still arrange transfer for angiography because the culprit lesion needs evaluation and the patient is young with a large territory at risk.