You are dispatched to a report of a disoriented man on the beach.
On arrival bystanders direct you to a 49 year old male who is sitting on a bench. An elderly couple states they were taking a walk and saw the man sitting on the bench and became worried about him due to his appearance.
The patient is pale and diaphoretic. He is lethargic and states that he doesn’t feel well.
He admits to slight chest discomfort on inspiration. He denies any significant medical history.
You place him on the gurney and load him in the back of your ambulance for a more detailed exam.
Vital signs are assessed.
- HR: 50
- RR: 16
- NIBP: 82/54
- SpO2: 94% on RA
Breath sounds are clear bilaterally.
The cardiac monitor is attached.
A 12 lead ECG is obtained.
What is your plan of treatment?
This is an impressive STEMI! Every single lead shows an ST-segment deviation.
This is a good case to show the difference between monitor mode and diagnostic mode. Look at the difference in lead II between the rhythm strip and the 12-lead ECG! In the rhythm strip the low frequency / high pass filter is set to 1 Hz. In the 12-lead ECG it is set to 0.05 Hz.
I did not receive the angiograms for this case but we can surmise that the culprit artery was either the RCA or LCX. When STE III > STE II it suggests RCA occlusion but in this case STE III = STE II (they look identical) so that’s no help!
Regardless, we can certainly say this is an inferior-posterior-lateral STEMI. Could there be right ventricular infarction? It really doesn’t matter because we should be withholding nitroglycerin based on the initial blood pressure.
It’s worth noting that we often see bradycardia and marginal blood pressures in the setting of acute inferior STEMI which is often a manifestation of the Bezold-Jarisch reflex which induces a state of hypervagotonia.
One interesting feature of the ECG is that the rate is 50 with narrow QRS complexes but the patient is not in sinus bradycardia. If you look at leads with the most isoelectic T-waves (lead I and lead V4) you can see a blip about 240 ms after the QRS complex. Is it a P-wave? Quite possibly. But this arrhythmia is likely to resolve following successful reperfusion.