This 57 yo male with no past medical history had sudden onset of chest pain while sleeping. He called 911 at midnight and his prehospital ECG (unavailable) showed acute MI and the cath lab was activated 20 minutes prior to arrival, giving cath lab personnel time to drive into the hospital as the patient was being transported.
The Door to Balloon time was 34 minutes, time from symptom onset to opening of a 100% occluded wraparound (type III) LAD was about 80 minutes (very short). Nevertheless, the patient suffered a large myocardial infarction, with a peak troponin I of 290 ng/ml. There was a large anterolateral, anteroseptal, anteroapical, and distal inferior wall motion abnormality, with EF of 30-35%. The convalescent echo several weeks later will tell us how much of this is due to (irreversible) infarction vs. temporary "stunning". His follow-up ECG the next day is shown below.
|There are "reperfusion" T-waves in V1-V6 and I, aVL. There is a QS-wave in V2, and QR-wave in aVL, and poor R-wave progression in V3 and V4, all diagnostic of anterolateral MI, subacute.|
1) hyperacute T-waves, with loss of R-wave amplitude such that the T-wave towers over the R-wave
2) that the computer again misses a clearly diagnostic STEMI
3) that a large STEMI may not meet any millimeter criteria for STEMI (there are several published criteria, and the only one met here is 1 mm in two consecutive leads, an extremely non-specific criterion. In fact, no STE millimeter criterion has adequate accuracy)
4) that even with rapid reperfusion, much myocardium may be lost.