The normal ST is isoelectric. Elevation or depression is judged in relation to the PR segment.
Some changes may be normal:
Limb lead depression or elevation up to 1mm and in left precordial leads of up to 2mm.
J‐depression: the J point (junction between the QRS and ST segment) is depressed without sustained ST depression i.e. depression with a gentle upward slope.
Early repolarisation in adolescents: the ST segment is elevated and concave in leads with an upright T wave.
Others are pathological, either:
a downward slope of the ST followed by a biphasic inverted T or
a sustained horizontal ST segment depression 0.08 sec or longer
Pathological ST segment changes are commonly associated with T wave changes and occur in:
Pericarditis
Myocardial ischaemia or infarction
Severe ventricular hypertrophy (ventricular strain pattern)
ST segment
Tessa Davis. ST segment, Don't Forget the Bubbles, 2014. Available at:
https://doi.org/10.31440/DFTB.5767
The normal ST is isoelectric. Elevation or depression is judged in relation to the PR segment.
Some changes may be normal:
Others are pathological, either:
Pathological ST segment changes are commonly associated with T wave changes and occur in: