ST elevation across V1-V4, from an occluded left anterior descending artery.
The left anterior descending artery supplies the septum and anterior wall, so expect ST elevation in V1-V4 (septal V1-V2, anterior V3-V4), often preceded by broad hyperacute T waves. Don't go looking for much reciprocal change: without elevation in I and aVL, reciprocal depression is minimal or absent. The threshold is higher in V2-V3: 2.5 mm in men under 40, 2 mm in men over 40 and 1.5 mm in women. In every other lead it's 1 mm.
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.
ST elevation across V1-V6 and in I and aVL, with reciprocal depression in III and aVF.
A QRS of 0.12 s or more with a deep, broad S (QS or rS) in V1 and a broad R with no Q wave in I, aVL, V5 and V6.
In V1-V2, the ST rises over 2 mm at the J point and falls in a coved, convex curve straight into an inverted T wave.
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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