Which myocardial infarction type is classically associated with ST-segment elevation on the ECG and is treated with reperfusion therapy?

Which myocardial infarction type is classically associated with ST-segment elevation on the ECG and is treated with reperfusion therapy?

• A. NSTEMI
• B. STEMI
• C. Type 2 MI
• D. Q-wave MI

Answer: (B)

ST-segment elevation on the ECG signals a full-thickness (transmural) myocardial infarction caused by a complete occlusion of a coronary artery. This pattern defines a STEMI, which is treated with urgent reperfusion therapy to quickly restore blood flow and minimize heart muscle damage. Reperfusion is usually achieved with primary PCI if it can be done promptly; if PCI isn’t available within the recommended window, thrombolytic therapy is used. In contrast, NSTEMI often shows ST-segment depression or T-wave inversion without ST elevation and is managed with anti-ischemic and antithrombotic therapy rather than immediate reperfusion. Type 2 MI results from a mismatch between oxygen supply and demand and may not present with ST elevation. Q-wave MI typically indicates a prior infarct with established scar rather than an acute STEMI.

ST-segment elevation on the ECG signals a full-thickness (transmural) myocardial infarction caused by a complete occlusion of a coronary artery. This pattern defines a STEMI, which is treated with urgent reperfusion therapy to quickly restore blood flow and minimize heart muscle damage. Reperfusion is usually achieved with primary PCI if it can be done promptly; if PCI isn’t available within the recommended window, thrombolytic therapy is used. In contrast, NSTEMI often shows ST-segment depression or T-wave inversion without ST elevation and is managed with anti-ischemic and antithrombotic therapy rather than immediate reperfusion. Type 2 MI results from a mismatch between oxygen supply and demand and may not present with ST elevation. Q-wave MI typically indicates a prior infarct with established scar rather than an acute STEMI.