Neck and Jaw Pain in a patient with a Pacemaker. Sgarbossa Negative. But How about the Modified Sgarbossa Criteria?

I was at home on a late Saturday evening when this first ED ECG was texted to me:Atrial and Right Ventricular Paced Rhythm(most pacing is RV pacing --- there is increasing use of biventricular pacing)What do you think?  What did I say?" It looks like Occlusion Myocardial Infarction (OMI).  If the clinical presentation is consistent with acute MI, Activate the Cath Lab. "I added this to my text response:  " The EKG meets the Smith modified Sgarbossa criteria, so I think there is no choice but to take a look at his coronary arteries, but for some reason I do not feel convinced in my own mind as I look at it. " I think I was not totally convinced because all the ST segments have very normal upward concavity.  But we have shown that, in LBBB, upward convexity is only present in 50% of leads which meet the Modified Sgarbossa Criteria and are True Positives.Full Analysis: Leads II, and V4-V6 all have discordant ST Elevation with an ST/S ratio greater than 25%.  In our PERFECT study by Dodd KW et al. (Paced ECGRequiringFastEmergentCoronaryTherapy), which I am told will be published online today in the Annals of Emergency Medicine, just ONE LEAD with such a ratio was highly specific for OMI.  See post on the the PERFECT study paper here coming soon.    As for ST Depression in V2: It isNOT concordant, as the Original Sgarbossa Criteria requires.  It is Discordant, but it isexcessively discordant ...
Source: Dr. Smith's ECG Blog - Category: Cardiology Authors: Source Type: blogs