ST-segment elevation
— To be considered pathologic, the ST elevation, measured at the J point, must be ≥0.1 mV, except for leads V2 to V3, where it needs to be ≥0.2 mV in males ≥40 years, ≥0.25 mV in males <40 years, and ≥0.15 mV in females [3]. ST-segment elevation can be caused by states other than myocardial ischemia however.
ST-segment depression
— ST-depression is defined by a horizontal or down-sloping ST segment that is depressed ≥0.05 mV below the baseline, measured at 0.08 seconds after the J point, in two contiguous leads (waveform 2). The TP segment should be used as the baseline, and the PR interval used only if there is no obvious TP-segment. The strongest correlation with ischemia is with a downsloping or horizontal ST-segment depression. Upsloping ST-segment depression has a weaker correlation, as this type of ST-segment depression may be seen as a normal change with sinus tachycardia.
