Guess the culprit with ST Elevation in posterior leads

A middle aged man had off and on chest pain for 2 weeks, then 2 hours of more severe and constant pain.Here was his ED ECG, which was identical to the prehospital ECG.  He did not get prehospital activation.What do you think?There is sinus rhythm with ST depression in I, II, aVF and V2-V6.  It is maximal in V3 and V4.  This usually means posterior MI,whether the T-wave is upright or not.There is also some ST elevation in aVR, which must be present whenever there is ST depression in I and II (a lead between I and II is (-) aVR, opposite aVR; if ST segments in I and II are negative, then theymust also be negative in the lead that is between them [(-) aVR].  If (-) aVR has ST depression, then aVR must have ST elevation.ST Elevation in aVR is not the same as STE in other leads because there is no underlying myocardial wall; there are only atria!  So STE in aVR is reciprocal to ST depression elsewhere.ST vectorIn this ECG, the ST vector is both posterior (away from V3 and V4), upward, away from aVF, and rightward (away from I, II, V5, V6 and towards aVR.  It is mostly posterior, as the greatest ST depression is in V3 and V4.When the ST vector is primarily posterior, the diagnosis is usually posterior STEMI._____________________I just read Ken ' s comments before publishing.He wrote below that there is 2 mm of STE in aVR.  I did not and do not measure it that way.So I went back to the original ECG and magnified it:I put the top of the line just un...
Source: Dr. Smith's ECG Blog - Category: Cardiology Authors: Source Type: blogs