The ECG distinction between ventricular aneurysm vs. true STEMI is a tough one. Aside from reviewing the patient's history, here are a few pearls that may help.
1. Both entities cause Q-waves and STE that can be concave or convex upwards. However, aneurysms shouldn't cause reciprocal depression, whereas a true STEMI often does. 2. Serial ECGs and old ECGs are helpful. The aneurysm shouldn't change from a recent ECG or with serial testing, but STEMI ECGs often do, even over the course of 1-2 hours. Look for any changes in ST segments, T-wave morphology changes, or development of Q-waves. 3. Aneurysms are almost always associated with STE in the anterior leads (because most aneurysms involve the anterior wall). STEMI can involve anterior, lateral, or inferior wall. 4. Aneurysms are almost always associated with Q-waves, whereas STEMI may not (yet) have Q-waves.
