A middle-aged male presented with “burning” mid chest pain, with radiation to bilateral shoulders (pain radiating to both shoulder is very specific for ischemia).  It started about 5 hours prior to arrival.  He obtained little relief from nitro x 3 by EMS.  There was a history of previous MI, with a stent in the 1st Obtuse Marginal.  He had taken his Plavix for 6 months, then discontinued and also stopped taking his antihypertensives and statin.  He continued to smoke about 1.5 pks per day.

Here is his ECG:

Junctional Bradycardia (this is sinus arrest with junctional escape, and is highly suggestive of ischemia).   There is a pathologic Q-wave in lead III (old? new?).   There is slight ST depression in leads I, II, and V3-V6 (fairly specific for ischemia).  Down-Up T-wave in aVL: very specific for ischemia!  There are slightly hyperacute T-waves in inferior leads (probable ischemia).

These are subtle findings.  No single finding is diagnostic of ischemia but he has a very specific combination of factors:

1. typical pain

2. h/o coronary disease

3. pain radiating to both shoulders

4. junctional bradycardia

5. Q-waves

6. ST depression

7. Down-Up T-wave in aVL

7. Possible hyperacute T-waves 

All of these together, but none of them by themselves, diagnose acute MI.

One of my former residents diagnosed this as inferior MI and activated the cath lab.  I love it when my residents become better than I at reading ECGs!

There was a 100% acute occlusion of the RCA, with ischemia of the SA node causing sinus arrest.

Lesson:

1. When highly suggestive ECG signs of ischemia combine with a high pretest probability and refractory ischemic pain, activate the cath lab even if the ECG does not meet STEMI criteria.