Elderly with Paced Rhythm, Possible Ischemic symptoms, and an Equivocal Smith Modified Sgarbossa ECG

An 80 year old presented with a couple days of SOB, weakness, and diaphoresis.  There was no chest pain.Here was her initial ECG:What do you think?-There is a paced rhythm. -There is some concordant ST Elevation (STE) in V5 and V6. -There is ST depression in V2. -There is minimal concordant ST depression in V3 (remember there should be, if anything, appropriately discordant STElevation).The treating physician did not think that there was sufficient concordant STE in V5 and V6.  He saw the ST depression in V2, but did not see it as concordant or excessively discordant because the R-wave and S-wave were equal.However, when the QRS is isoelectric in LBBB or paced rhythm, there should be zero ST shift!  Non-ischemic (baseline, normal) ST shift in Paced Rhythm and LBBB is due to Appropriate Discordance.  If there is no dominance of the R-wave or S-wave, there cannot be appropriate discordance. Any ST shift in these cases is abnormal (ischemic).So this is clearly ischemic ST depression.In addition: While it is true that the concordant ST Elevation in V5 and V6 is not quite 1 mm, any concordant STE is highly suspicious.  Moreover, this is in the context of a very low voltage R-wave, so a small amount of concordant STE is much more significant.This ECG is diagnostic of Occlusion MI (OMI).The provider did not immediately activate the cath lab.There were a couple subsequent ECGs before angiogram which show some evolution (worsening)Incr...
Source: Dr. Smith's ECG Blog - Category: Cardiology Authors: Source Type: blogs