Heart palpitations are an awareness of your heartbeat.

Palpitations might feel as though your heart is 'racing', thumping or skipping beats. You might notice them:

• during exercise
• at times of stress
• after consuming caffeine or nicotine.

Heart palpitations may or may not be associated with an abnormal heart rhythm.

Arrhythmias

Arrhythmias are disturbed rhythms of your heartbeat.

There are many different types of arrhythmias. Some may make your heart skip or add a beat now and again, but do not affect your overall health. Other arrhythmias are more serious and without treatment, can affect your heart's pumping action, leading to dizzy spells, shortness of breath, faintness or serious complications.

Many arrhythmias can be treated with medicine, surgery or other medical procedures. 

Different abnormalities of your heart's electrical system cause different kinds of arrhythmias, including bradycardia and tachycardia.

Bradycardia (a slow heart beat) 

Bradycardia is when your heart beats slowly. It may be normal (for example, with improved physical fitness), but is also caused by many physical disorders.

Bradycardia is serious if your heart beats so slowly that it can't pump enough blood to meet your body's needs. If you don't get treatment for it, bradycardia can make you feel very tired, dizzy, light-headed or faint.  

Tachycardia (a fast heart beat)

Tachycardia is when your heart beats too fast. Common types of tachycardia include atrial flutter and atrial fibrillation. It can be a normal response to physical activity, but some types of tachycardia are cause for concern.

Ventricular tachycardia is a potentially life-threatening condition that needs to be treated as a medical emergency. Treatment involves giving your heart an electric shock using a defibrillator. The electric shock 'resets' your heart so it can start beating normally again.

To find out about the causes, diagnosis, treatment and management of palpitations, use the navigation bar at the right of this page.

Resources

Long QT syndrome - information sheet (2010)  Download