ST-segment elevation on ECG is most consistent with which acute condition?

ST-segment elevation on ECG is most consistent with which acute condition?

• A. Unstable angina
• B. NSTEMI
• C. Pericarditis
• D. STEMI

Answer: (D)

ST-segment elevation reflects acute transmural injury from a complete occlusion of a coronary artery, which is the hallmark of a ST-elevation myocardial infarction. When a coronary artery is suddenly blocked, the entire thickness of the heart wall in that region is deprived of blood, causing a current of injury that elevates the ST segment in the corresponding ECG leads. This pattern is typically localized to leads over the affected territory and may show reciprocal ST depression in opposite leads. Unstable angina and NSTEMI usually do not show new ST-segment elevations; they more often present with ST-segment depression or T-wave inversions, reflecting subendocardial ischemia rather than full-thickness injury. Pericarditis can cause ST elevations as well, but those are usually diffuse (widespread) and often accompanied by PR-segment depression, not confined to a single coronary territory. So, the presence of new, localized ST-segment elevations best fits STEMI. Urgent reperfusion therapy is essential to restore blood flow.

ST-segment elevation reflects acute transmural injury from a complete occlusion of a coronary artery, which is the hallmark of a ST-elevation myocardial infarction. When a coronary artery is suddenly blocked, the entire thickness of the heart wall in that region is deprived of blood, causing a current of injury that elevates the ST segment in the corresponding ECG leads. This pattern is typically localized to leads over the affected territory and may show reciprocal ST depression in opposite leads.

Unstable angina and NSTEMI usually do not show new ST-segment elevations; they more often present with ST-segment depression or T-wave inversions, reflecting subendocardial ischemia rather than full-thickness injury. Pericarditis can cause ST elevations as well, but those are usually diffuse (widespread) and often accompanied by PR-segment depression, not confined to a single coronary territory.

So, the presence of new, localized ST-segment elevations best fits STEMI. Urgent reperfusion therapy is essential to restore blood flow.