Horizontal ST depression across many leads, deepest in V4-V6, I and II, with ST elevation in aVR (bigger than any in V1): global subendocardial ischemia, not a territory.
The ST is down in most leads and up in aVR. That aVR elevation is the mirror image of all the depression, not injury under aVR, so this is not a STEMI territory. It's ischemia of the inner layer of the whole ventricle, and it doesn't point to one artery. Sometimes it's severe left main or three-vessel disease, but far more often it's supply and demand: a tachycardia, bleeding, sepsis, hypotension, severe hypertension. Treat the driver, report it as diffuse ST depression with ST elevation in aVR, and take the patient somewhere with a cath lab. Mortality is high even though it's usually not an occlusion.
Each is a standard 12-lead: 2.5 seconds of each lead in four columns, with 10 seconds of lead II along the bottom, drawn to scale (25 mm a second, 10 mm a millivolt). The measurements are under each one.
Horizontal ST depression in V1-V3 with tall R waves and upright T waves, and ST elevation in the posterior leads V7-V9.
Upsloping ST depression of more than 1 mm at the J point in the chest leads, running into tall, symmetric T waves, with no ST elevation there and slight ST elevation in aVR.
ST elevation in I, aVL, V5 and V6, with reciprocal depression in III and aVF.
Sinus rhythm, a normal axis, normal intervals, R waves growing from V1 to V5, and no ST elevation or depression.
The ECG tool in the app gives you a new 12-lead every time and walks you through reading it: rate, QRS, axis, then where the ST is up and down. It's part of the Paramedic level, and you can try 5 ECGs a day free.
Try the 12-lead drill
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