A 37 year old with a history of DM on metformin complained of acute onset of burning chest pain. He called 911. They did an ECG but it is not available. However, the medics were very concerned and brought him to the critical care area with a high suspicion of STEMI. Here is the initial ECG
This shows sinus rhythm and abnormal septal Q-waves in V1 and V2, with what appear to be hyperacute T-waves in V2-V4. The computer read ***Acute MI***. Though the early repol vs. anterior STEMI formula , strictly speaking, should not be used because there are Q-waves, if you did, you would use STE60V3 = 3.5 mm, RAV4 = 8.5 mm, and computerized QTc = 413. This gives a value of 25.8, indicating anterior STEMI.
So this ECG would seem to support anterior STEMI. The cath lab was about to be activated. However, there was a previous ECG from 3 months prior:
This is nearly identical, and establishes that the first ECG is not acute STEMI.
The patient ruled out for MI by serial troponins.
Is there an old MI present? The best way to evaluate that would be an echocardiogram. However, none was ever done.
Whether this patient has coronary disease is unknown. His ECG suggests it, but does not prove it.
When the patient had presented the first time, he had chest pain, and they were unconcerned about the ECG and they got lucky as he simply ruled out by troponins.
Lesson Whenever the ECG is abnormal, look for a previous one before coming to conclusions!