A 60-something has chest tightness, palpitations, and ST depression V1-V3

A 60-something has chest tightness, palpitations.  Charts showed a history of some mitral regurgitation and an enlarge left atrium, as well as hypertension treated with a thiazide diuretic.A prehospital ECG showed ST Depression in V1-V3 and the medics were concerned for posterior STEMI.On arrival, the patient was in minimal distress, stated that he " always has chest tightness " but that his " heart started jumping around " one hour prior.Pulse was 128 and irregular, BP was 141/75.Here is the 12-lead:Atrial Fibrillation with slightly rapid response.ST Depression maximal in V2 and V3.What do you think? What do you want to do?ST Depression in V2, V3 is most often due to " posterior " transmural ischemia (now called " lateral " by a convention that I disagree with because posterior and lateral MI are different on the ECG).However,sometimes it is due to subendocardial ischemia.  Subendocardial ischemia " does not localize " , meaning that if this is subendocardial, you cannot say for certain that it is of the anterior wall.  Furthermore, subendocardial ischemia usually has an STD vector towards II and V5, with areciprocal STE vector towards aVR.Atrial Fib with RVR is often associated with subendocardial ischemia, so I thought this might very well NOT be posterior MI, but rather subendocardial ischemia.  Usually such ischemia from atrial fibrillation is with a very fast ventricular response (~150); here it is not so fast. A bedside echo was unable to find ...
Source: Dr. Smith's ECG Blog - Category: Cardiology Authors: Source Type: blogs