Figure 1: ECG Strip
ST elevation and ST depression are forms of ST segment abnormalities caused by myocardial ischaemia or infarction. The ST segment is the section of the ECG between the end of the S-wave and the beginning of the T-wave. ST elevation occurs when the ST segment is elevated in comparison to the PR segment. Specifically, the ST segment represents "the interval between ventricular depolarization and repolarization.''
- Clinical circumstances surrounding ECG changes are crucial in diagnosing the specificity of ST segment abnormalities.
- Various factors, in addition to myocardial disease, can affect ST segment configuration:
- Electrolyte abnormalities of potassium, magnesium, and calcium
- Neurogenic factors, such as hypoglycemia and hyperventilation
- Atrial repolarization
- Ventricular conduction abnormalities and rhythms beginning in the ventricles
Figure 2: ECM Analysis, Record e0114, Lead V4 The ST segment is a lighter shade of blue than the PR segment on the ECM, indicating more positive amplitude and the presence of ST elevation.
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