There is excessively discordant ST elevation in V1 & V2. ST/S ratio in V1 is 5/15 = 33%.
There is excessively discordant ST elevation in aVR. The ST/S ratio is 3/8 = 37%.
There is also excessively discordant ST depression in lead I (ST/R ratio = 100%) and V4 (ST/R ratio = ~60%).
If you accept, as Dr. Smith does, that the Smith Modified Sgarbossa criteria can be used not only in LBBB, but also in ventricular escape rhythms, then any one of these findings meets those criteria. The STE in V1 as well as the STD in I and V4 are particularly specific for occlusion.
Furthermore, there is an abnormal amount of STD in V5 and V6 (ST/R ratio almost 20%).
Smith Modified Sgarbossa Criteria for LBBB and Ventricular Paced Rhythms
Rule 1: (80-90% sensitive, 95% specific for occlusion)
Any one of:
1. 1 mm concordant STE in any one lead
2. 1 mm concordant STD in any one of V1-V3
3. At least 1 mm discordant STE that is ≥25% of the preceding S-wave in at least one lead
Rule 2: (Only 64% sensitive, but 98% specific for occlusion)
Any one lead with proportionally discordant STE or STD of at least 30% of the preceding R- or S-wave
One more finding!! PVCs!!!! The 5th beat is a PVC and has an RBBB morphology (large R-wave in aVR with wide S-wave in V5). This implies a PVC originating in the left ventricle. RBBB morphology PVCs should never have an ST segment that is concordant to the QRS, as it is here in lead aVR. This is diagnostic for STEMI.
See these cases:
A previous ECG was obtained:
There is a preexisting LBBB with proportionally normal discordant ST elevation, which makes the ST changes in the new EKG obvious by comparison.
This also suggests that the rhythm in the first ECG is supraventricular, because the QRS morphology is LBBB. However, if you look closely at V5 and V6 in the first ECG, both have a very narrow peak compared to this old ECG which is much more typical LBBB.
Smith comment: I am still not completely certain as to whether the first ECG is supraventricular with left bundle branch block, or with RV escape. But it does not matter: the patient has a coronary occlusion until proven otherwise. She needs immediate pacer pad placement and angiography/PCI.
The clinicians caring for the patient were concerned about an acute coronary occlusion. The cardiologist was in hospital and was paged to the resuscitation area. Over the course of the following few minutes, the patient gradually recovered to her normal mental status. She remained normotensive and entirely asymptomatic.
As the cardiologist arrived, a change in the QRS morphology was noted on the monitor and a repeat ECG was obtained: