A patient is experiencing severe chest pain unrelieved by nitroglycerin. Which diagnostic testing supports the possibility of a myocardial infarction instead of unstable angina?

Question

Group of answer choices

Blood tests indicate elevation of Troponin

Coronary artery calcium computerized tomography (CT) scan shows calcification

Electrocardiogram (ECG) results exhibit a depressed ST segment

An ambulatory ECG is positive for cardiac stress

Answer 1

In the context of differentiating between a myocardial infarction (MI) and unstable angina, the most definitive diagnostic test would be:

Blood tests indicate elevation of Troponin.

Troponin is a protein released when the heart muscle has been damaged, and its elevation is a strong indicator of myocardial infarction. In contrast, unstable angina typically does not result in an elevation of troponin levels, as there is no significant myocardial necrosis.

The other options (coronary artery calcium CT scan, depressed ST segment on ECG, and a positive ambulatory ECG for cardiac stress) may provide useful information but are not definitive for diagnosing a myocardial infarction in the same way that an elevated troponin level is.