Tachycardia means that your heart is beating much faster than normal, usually more than 100 beats per minute. Some forms of tachycardia are not serious and easily treated while others can be life-threatening. This page explains tachycardia and helps you understand when it might be a problem, and when it is a normal event.

What is tachycardia (fast heart rate)?

Your heart’s job is to pump blood. It helps move oxygen and nutrients around your body to keep it working. It also helps your body get rid of waste by pumping blood to your lungs, your kidneys and all your other organs.

But sometimes a heart pumps too fast. This is called tachycardia, which may be normal during exercise or as a response to stress or it may be an abnormal rhythm that causes a fast heart rate.

What are the types of tachycardia (fast heart rate)?

There are 3 types of tachycardia.

• Supraventricular (above the ventricle) — where problems with the electrical signals in the upper chambers (atria) of the heart cause the heart to beat faster. This reduces blood flow to the rest of your body because your heart can't pump blood as effectively. Two common types of supraventricular tachycardia are atrial flutter and atrial fibrillation.
• Ventricular — where problems with the electrical signals in the lower chambers (ventricles) of the heart cause the heart to beat faster. This affects its ability to pump blood to the rest of your body.
• Sinus tachycardia — where the natural pacemaker in your heart sends electrical signals faster than normal. This can be in response to a stressor described below, or it can be a sign of anaemia, problems with the thyroid gland or general ill health.

What causes tachycardia (fast heart rate)?

Sometimes tachycardia is normal — sinus tachycardia is just the way the body responds to stressors like fever, fear, anxiety and strenuous exercise. This is usually not a concern.

But sometimes tachycardia signifies a health problem. Arrhythmias are one of the main risk factors for stroke.

Causes of abnormal tachycardia include:

• anaemia
• some medicines
• thyroid gland problems
• heart attack
• other problems with the heart

What are the symptoms of tachycardia (fast heart rate)?

It is possible to have tachycardia and have no symptoms.

People with symptoms most often feel:

• dizzy and light-headed
• palpitations, when you feel your heart pounding or beating irregularly
• short of breath
• chest pain

In severe situations, people with tachycardia can have a heart attack or become unconscious.

Consequences of tachycardia

Sinus tachycardia that has no underlying medical cause usually has no consequences — whatever has caused it eventually goes away, and the heart goes back to normal.

If not treated, other types of tachycardia can lead to:

• stroke
• heart failure
• cardiac arrest

How is tachycardia diagnosed?

If you notice your heart racing or beating irregularly, you should see your doctor.

Your doctor will talk to you and examine you. Tests to diagnose tachycardia include:

• Electrocardiogram (ECG) — checks how effectively the electrical signals of your heart are working.
• Exercise stress test — monitors how your heart responds to different levels of physical activity.
• Holter monitor — a monitor of the heart beat rhythm that is worn for 24 hours.
• Echocardiogram — an ultrasound that looks at the structure of the heart valves, walls and chambers.

How is tachycardia (fast heart rate) treated?

The treatment for tachycardia depends on the type, but could include:

• changes to your lifestyle:
  • reducing stress
  • drinking less caffeine or alcohol
  • quitting smoking
  • getting more sleep
• medicines to slow the heart
• medicines to prevent the abnormal rhythm
• treatment of medical conditions leading to the abnormal rhythm (e.g. treating thyroid conditions)

Some people will need a defibrillator to help get the heart into the right rhythm. Some will need radioablation — a surgical procedure that inactivates the tiny parts of the heart causing electrical signal problems.

How is tachycardia (fast heart rate) prevented?

A healthy lifestyle with a good diet and regular exercise to achieve a healthy weight can help.

Where to get help

Your tachycardia may not always need treatment, but it needs monitoring as it can indicate serious problems.

If you have any concerns about your heart:

• see your doctor immediately
• use the healthdirect Symptom Checker
• read more about keeping your heart healthy