It’s important to understand which leads represent which anatomical territory of the heart, as this allows you to localise pathology to a particular heart region.

The ECG Made Easy - 9780702074578 - US Elsevier Health The ECG Made Easy - 9780702074578 - US Elsevier Health

A pathological Q wave is > 25% the size of the R wave that follows it or > 2mm in height and > 40ms in width.You can then combine this with some anatomical knowledge of the heart’s blood supply to work out which artery is likely to be affected (e.

The ECG Made Easy - 9th Edition - Elsevier The ECG Made Easy - 9th Edition - Elsevier

When the electrical activity within the heart travels towards a lead, you get a positive deflection.It directs users of the electrocardiogram to straightforward and accurate identification of normal and abnormal ECG patterns.

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The T waves are also raised (in contrast to a STEMI, where the T wave remains the same size and the ST segment is raised).

This causes the deflection in lead I to become negative and the deflection in lead aVF/III to be more positive. You should document your interpretation of the ECG in the patient’s notes (check out our guide to documenting an ECG). Each name’s first and last letter helps you recognise the ECG features of the associated bundle branch block. The ST segment is an isoelectric line representing the time between depolarisation and repolarisation of the ventricles (i.