You are handed an EKG for a 50 yo man with moderate chest pain for 2 hours now and no associated symptoms typical for ACS, PE, aortic dissection, or any other red flags of chest pain. He has no prior EKG’s on file.
Is this early repolarization or ST elevation MI?
Should I activate the cardiac catheterization lab?
Furthermore, there is a formula to differentiate early repolarization vs STEMI, per Dr. Smith’s publication6:
(1.196 x STE60V3) + (0.059 x QTc) – (0.326 x RA V4)
STE60V3 = STE elevation height at 60 msec (1.5 small boxes) after the J-point in lead V3 (mm)
QTc = The computer-read QTc interval
RA V4 = R wave amplitude in lead V4 (mm)
A result of > 23.4 is predictive of a LAD occlusion causing a STEMI, rather than early repolarization.
P.S. The above EKG image shows early repolarization.
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