Tests for heart and circulatory conditions
Tests are used to diagnose a heart condition or to see how healthy your heart is. Find out what to expect from some of the most common tests.
Arrhythmia explained
What is an arrhythmia?
An arrhythmia is an abnormal heart rhythm.
Your heart needs to beat regularly to help pump blood around your body. There is an electrical system in your heart that sends out electrical impulses to help it to beat regularly and in time.
If the electrical impulses are not working properly, you’ll have an abnormal heart rhythm. This can cause your heart to beat too slowly, too quickly or not regularly.
Are arrhythmias dangerous?
Most arrhythmias are not dangerous, but some can be. That’s why it’s important to get help if you need it.
Dial 999 for an ambulance if:
- you have palpitations, feel like you cannot breathe and you have chest pain or feel faint or dizzy.
Speak to your GP about your symptoms if:
- your palpitations last a long time, do not improve or get worse
- you have a history of heart problems
- you're concerned about the palpitations.
Types of arrhythmias
What are the different types of arrhythmias?
There are different types of arrhythmias, the most common are:
- Atrial fibrillation is when your heart does not beat regularly. Your heart may also beat too quickly, or too slowly.
- Supraventricular tachycardia (SVT) is a very fast heart rhythm. There are different types of SVT. Most are caused by electrical impulses not travelling normally from the top chambers of your heart to the bottom chambers of your heart.
- Atrial flutter is usually a fast heart rhythm where the top chambers of your heart contract quicker than the lower chambers. This can cause the top chambers to beat extremely fast, sometimes up to 300 beats per minute (bpm).
- Tachybrady syndrome (sick sinus syndrome) causes periods of very fast (tachycardia) or very slow (bradycardia) heartbeats. This is because the heart’s electrical system is not working as it should.
- Heart blocks are caused by a delay or blockage in your electrical system between the top and bottom chambers of your heart which can cause a slow heart rate.
Is your heart rate fast or slow?
- Sinus tachycardia is when your heart beats in a regular way but it’s faster than 100 bpm.
- Sinus bradycardia is when your heart beats in a regular way but it’s slower than 60 bpm.
If you have sinus tachycardia or bradycardia it does not mean there's something wrong with your heart and you might not need treatment. Sometimes it can be caused by another condition which you may need treatment for. Your doctor might want to send you for tests to find out more.
Signs and symptoms
What are the signs and symptoms of an arrhythmia?
The symptoms you have depend on what type of arrhythmia you have. The most common symptoms include:
- palpitations (a thumping or fluttering sensation in your chest)
- dizziness
- feeling as if you may faint or ‘black out’
- feeling like you cannot breathe
- chest discomfort
- feeling tired.
Causes
What causes an arrhythmia?
Some conditions can cause an arrhythmia, such as:
You can sometimes develop arrhythmias after some types of heart surgery.
Some arrhythmias can be caused by inherited conditions, such as Long QT syndrome, Brugada syndrome, catecholaminergic polymorphic ventricular tachycardia (CPVT) or progressive cardiac conduction defect (PCCD).
If this is the case for you, your doctor will talk to you about having family members tested. Although this can be scary, it can help them know if they need treatment now or in the future.
Other common triggers of an arrhythmia include:
- viral illnesses such as flu, the common cold or norovirus
- recreational drugs
- alcohol
- smoking
- caffeine
- medicines (over the counter and prescribed).
Diagnosis
How are arrhythmias diagnosed?
Your GP might refer you for tests including:
- an ECG
- an echocardiogram
- an electrophysiological (EP) study.
An ECG may include different tests such as a 24hr ECG, exercise ECG, and an implantable loop recorder.
Treatment
How are arrhythmias treated?
Your treatment will depend on your type of arrhythmia. Common treatments include:
- medicine
- cardioversion
- catheter ablation
- having an implantable cardioverter defibrillator (ICD) or pacemaker fitted.
Life with an arrhythmia
How will an arrhythmia affect my life?
Most arrhythmias are manageable. This means that with the right treatment you can carry on living as you were before you were diagnosed.
Living with an abnormal heart rhythm can be emotionally challenging for you and your family. It's important to manage anxiety and stress and get support from your GP or loved ones if needed.
You might have to think about practical matters like driving, going on holiday and returning to work after being diagnosed with an arrhythmia.
If your ability to drive is affected, you must let your insurance company and the DVLA know. Your GP can let you know if you need to do this.Talk to your manager or occupational health department if you have one, if you think your work may be affected.
Get support
- Speak to our cardiac nurses by phone, call back, email or online chat on Heart Helpline (Monday to Friday, 9am to 5pm).
- Sign up to Heart Matters magazine for online information packed with health and lifestyle advice.
Listen to this information or read it in another language
Listen to this page
00:00/00:00
Information about arrhythmias is available in Arabic, Bengali, Gujarati, Polish, Punjabi, Romanian, Urdu and Welsh.
You can trust our health information
We've followed an eight-step process to make sure this content is reliable, accurate and trustworthy.
Learn how we make our health content.More information
Treatments for heart and circulatory conditions
You may be having planned or emergency treatment. We explain what to expect, how it will help and what will happen afterwards.
Support
Being diagnosed, or living with a heart or circulatory condition can be overwhelming, but we're here to help.