Key terms for electrocardiograms

Tachycardia

What is it?

Abnormally fast heart beat of over 100 beats per minute.

Causes

It is caused by problems with problems with electrical transmission to the heart.

SVT can be caused by an electrical signal from another part of the heart overriding the signal from the sinoatrial node.

Bradycardia

What is it?

An abnormally slow heart beat of below 60 beats per minute.

Causes

Problems with the sinoatrial (SA) node, sometimes called the heart's natural pacemaker

Problems in the conduction pathways of the heart (electrical impulses are not conducted from the atria to the ventricles)

Metabolic problems such as hypothyroidism

Damage to the heart from heart attack or…