Chest pain in a young woman with a normal troponin
A 29-year-old woman presents to the emergency department at 02:00 with 90 minutes of central chest pain that began at rest while watching television. She describes it as pressure radiating to the left jaw, with sweating and nausea. She has no cardiac risk factors, takes no regular medication, and has no recent illness. Examination: anxious, heart rate 104/min, blood pressure 118/74 mmHg, oxygen saturation 97% on room air, chest clear, no murmurs, no calf tenderness. The ECG shows 1 mm ST depression in leads V4-V6 with T-wave inversion. High-sensitivity troponin taken 70 minutes after symptom onset is 8 ng/L (upper reference limit 14 ng/L). The emergency department is busy and the on-call cardiology registrar is in the catheterization laboratory with another patient.
1. How do you interpret the troponin result, and what is your immediate management?
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A single troponin below the upper reference limit does not exclude acute coronary syndrome. The sample was drawn only 70 minutes after symptom onset, which is within the time window in which high-sensitivity assays may still be negative, and the patient has ongoing ischemic-sounding symptoms with dynamic-looking ECG changes. The correct interpretation is "not yet ruled out".
Immediate management: place her on continuous cardiac monitoring, obtain intravenous access, give aspirin 300 mg chewed unless contraindicated, and treat pain with nitrates if blood pressure allows. Repeat high-sensitivity troponin at 1 hour and again at 3 hours from the first sample and calculate the delta; a rise, or persistent symptoms with ECG changes, mandates urgent cardiology review regardless of the absolute value. Perform a focused bedside echocardiogram if available to look for regional wall motion abnormality, and obtain a chest radiograph.
Do not discharge her on a single negative troponin. Because the ECG shows lateral ST depression and T-wave inversion in a young woman, also consider takotsubo syndrome, spontaneous coronary artery dissection, pulmonary embolism, and myocarditis; each changes management. Escalate to the cardiology registrar by telephone with the ECG findings and the symptom timeline rather than waiting for the catheterization laboratory to become free, and document the conversation. If symptoms persist with ST depression, she meets criteria for urgent invasive assessment.
2. The 3-hour troponin is 210 ng/L with a rise of 202 ng/L. What does this change, and which diagnoses must now be actively excluded?
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A significant rise confirms acute myocardial injury and, with ischemic symptoms and ECG changes, establishes acute coronary syndrome until proven otherwise. She needs urgent coronary angiography, dual antiplatelet therapy per local protocol, anticoagulation, and admission to a monitored bed with cardiology involvement.
However, a young woman with a rise of this magnitude and lateral ECG changes must have alternative causes actively excluded, because the management differs substantially:
- Spontaneous coronary artery dissection: consider at angiography; if found, conservative management is often preferred over stenting, and dual antiplatelet therapy may need to be reduced.
- Takotsubo syndrome: look for apical ballooning on echocardiography or ventriculography and a triggering stressor.
- Myocarditis: ask about viral prodrome, check inflammatory markers, and consider cardiac magnetic resonance imaging after stabilization; avoid unnecessary coronary intervention if the angiogram is normal.
- Pulmonary embolism: pretest probability is low but a D-dimer and, if indicated, CT pulmonary angiography should be considered if the coronary anatomy is normal.
Document the reasoning and ensure she is not labelled simply as "anxiety" on the basis of her age and a single early negative troponin.