Glossary
Glossary
Amplitude:
The upward deflection of a wave or complex.
Atria:
The two upper chambers of the heart (left and right atrium).
Augmented limb leads:
aVR, aVL and aVF comprise the unipolar limb leads.
Bradycardia:
A rhythm speed of less than 60 beats per minute.
Calibration box:
A box on the ECG tracing, 10mm high and 0.12 seconds in width, that is used to ensure that it conforms to a standardised measurement.
Distal:
An anatomical term that describes the direction and distance from the midline. Distal is further from the midline than proximal.
Electrical axis:
The general direction the electrical impulses take through the heart.
Electrical conduction system:
A pathway of specialised cells that promote the conduction of impulses through the heart.
Electrodes:
The adhesive sensors placed on the skin to record the electrical activity of the heart.
Ischaemia:
Lack of blood flow to an area of heart muscle.
Lead placement:
The exact position on the body of the ECG electrodes.
Limb leads:
I, II, III, aVR, aVL, aVF comprise the limb leads.
Myocardial Infarction:
The medical term for a 'heart attack'. It occurs when the cardiac muscle is irreversibly damaged.
Normal sinus rhythm:
The hearts normal rhythm. The intervals are consistent and within the normal range.
Precordial leads:
Also known as the chest leads. They are labeled V1 - V6 or C1 - C6.
Proximal:
An anatomical term that describes the direction and distance from the mid-line. Proximal is nearer to the midline than distal.
Rate:
The number of times the heart beats per minute.
Tachycardia:
A rhythm speed greater than 100 beats per minute.