Which statement best characterizes NSTEMI?

• A. ST elevation in leads II and III
• B. NSTEMI is not a form of ACS
• C. NSTEMI may not show ST elevation on ECG but troponin elevation
• D. NSTEMI shows ST elevation in V1-V3 exclusively

Answer: (C)

NSTEMI means non-ST-elevation myocardial infarction, a type of acute coronary syndrome where there is myocardial injury with troponin release but without ST-segment elevation on the ECG. The absence of ST elevation reflects subendocardial, not transmural, injury. Troponin elevation confirms the presence of myocardial necrosis even when the ECG doesn’t show a classic ST-elevation pattern. This is why the statement that NSTEMI may not show ST elevation on ECG but troponin elevation is the best description.

ST elevations in specific leads, like II and III, point to a STEMI of the inferior wall, not NSTEMI. Saying NSTEMI is not a form of ACS is incorrect because NSTEMI is part of acute coronary syndrome. ST elevation in V1-V3 would suggest an anterior STEMI rather than NSTEMI.