The changes in the ECG are seen in the leads adjacent to the infarct. In the first few hours the T waves become abnormally tall (hyperacute with loss of their normal concavity) and the ST segments begin to rise.
In the first 24 hours the T wave will become inverted, as the ST elevation begins to resolve.
Pathological Q waves may appear within hours or may take greater than 24 hr.
Long term changes of ECG include persistent Q waves in 90%, persistent T waves; persistent ST elevation is rare except in the presence of a ventricular aneursym.
In non Q-wave infarcts, ST depression and T wave inversion occur without ST elevation.
There may be ST depression in the leads opposite to the site of the infarct.
Note that in insulin dependent diabetics a small infarct on ECG may 'hide' large haemodynamic changes.
For more detailed information and ECG examples then click here
Add information to this page that would be handy to have on hand during a consultation, such as a web address or phone number. This information will always be displayed when you visit this page