What is tachycardia (fast heart rate)?

Tachycardia means that your heart is beating faster than normal, usually more than 100 beats per minute. Your heart usually beats between 60 to 100 times per minute.

Your heart's job is to pump blood around your body to move oxygen and nutrients to your organs and to remove waste from those organs.

It is normal for your heart to beat faster in some situations — for example, when you exercise or when you are in a stressful situation. This way your heart can supply your organs with more oxygen and nutrients.

Sometimes tachycardia can be abnormal and a sign of disease. You might need urgent medical attention.

What are the symptoms of tachycardia?

If you have tachycardia, you may have no symptoms or you may have:

• weakness, dizziness and light-headedness
• palpitations — feeling your heart pounding or beating irregularly
• shortness of breath
• chest pain

In severe situations, tachycardia can cause you to become unconscious.

What causes tachycardia?

Tachycardia can sometimes happen as part of a normal and healthy response to stress — such as fear, anxiety, exercise, an infection or fever. This is helpful when your body needs to increase the blood flow to your organs. It is not usually a concern.

However, sometimes tachycardia is a sign of a health problem. It can be caused by:

• anaemia
• some medicines, illicit drugs or caffeine
• hyperthyroidism (overactive thyroid gland)
• ischaemic heart disease or a heart attack
• heart failure
• other problems with your heart such as cardiomyopathy (disease of the heart muscle)
• pain

When should I see my doctor?

You should see your doctor if you feel you have a fast heartbeat together with symptoms such as mild shortness of breath, dizziness or weakness.

How is tachycardia diagnosed?

Your doctor can diagnose tachycardia by:

• asking you questions about your medical history and symptoms
• doing a physical examination
• arranging tests

Tests to diagnose tachycardia include:

• electrocardiogram (ECG) — this test measures your heart rhythm
• Holter monitor — an ECG monitor worn wherever you go for 24 to 48 hours to record your heart rhythm continuously
• exercise stress test — this test monitors how your heart rate and rhythm respond to different levels of physical activity
• echocardiogram — this is a type of ultrasound that looks at the structure of your heart valves and chambers

Based on your test results, your doctor will diagnose what kind of tachycardia you have and what is causing it.

How is tachycardia treated?

Sinus tachycardia during exercise or stress is normal and does not need treatment.

Treatment for an abnormal tachycardia depends on what type of abnormal heartbeat you have and what is causing it.

Treatment options for tachycardia could include:

• treating the health condition that is causing your abnormal heartbeat
• making changes to your lifestyle, such as eating a healthy diet, exercising, quitting smoking and cutting down on alcohol
• medicines to slow down your heart rate
• medicines to prevent an arrhythmia
• medicines to prevent a blood clot
• Valsalva manoeuvre — a breathing exercise that slows down your heartbeat
• cardioversion — an electric shock to your heart to reset its rhythm

If you have undergone cardioversion, sometimes your doctor may recommend you get an implantable cardioverter defibrillator (ICD). This is a small device that can automatically deliver a shock to your heart if needed.

Some types of arrhythmias can be treated with catheter ablation. In this procedure, a small catheter is inserted into your heart through a large blood vessel in your groin. The area producing signals causing your irregular heart rhythm is found and destroyed using electricity.

What are the complications of tachycardia?

If you have sinus tachycardia with no underlying medical cause, you are unlikely to have any complications. Whatever has caused your sinus tachycardia will go away and your heart rate will return to normal.

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

• stroke
• heart failure
• cardiac arrest

Can tachycardia be prevented?

If you have been diagnosed with tachycardia, you can help prevent symptoms by taking the medicines that your doctor has prescribed.

Talk to your doctor about what you can do to prevent some of the health conditions that cause tachycardia. For example, you can prevent ischaemic heart disease and heart failure by:

• being physically active
• eating a healthy diet
• quitting smoking
• maintaining a healthy blood pressure
• maintaining healthy cholesterol levels
• losing weight if you are living with obesity

Resources and support

• The Heart Foundation website has information about heart conditions, treatment and support.
• To find a support group for children, go to HeartKids. Learn about the Victor Chang Heart Health Check
• Call healthdirect on 1800 022 222 at any time to speak to a registered nurse (known as NURSE-ON-CALL in Victoria) for more information and advice.

Looking for information for Aboriginal and/or Torres Strait Islander people?

Visit Heart Health, a website about your heart, heart problems, recovery and stories for Aboriginal and/or Torres Strait Islander people.

Other languages

Heart Foundation has a series of Healthy Heart Habits factsheets, with information on heart disease risk factors and what you can do about them, in many community languages.