Table 3.

ECG Changes at presentation in STEMI.

Typical
ST Elevation (at least 2 contiguous leads)
•2 mm (0.2 mV) in men or 1.5 mm (0.15 mV) in women in leads V2–V3
•1 mm (0.1 mV) in other contiguous chest leads or the limb leads
New or presumably new LBBB

Atypical
STEMI in Evolution
•Hyperacute T-wave changes
Evolving/Evolved STEMI
•Q waves with T wave inversion with variable ST elevation
Posterior wall MI
•ST depression in 2 precordial leads (V1–V3) + positive T waves in V1
Left main or proximal left anterior descending artery occlusion
•ST depression in multiple leads with ST elevation in lead aVR and V1(aVR > V1: left main, V1 > aVR: proximal LAD)