Tests for heart rhythm problems

24-hour ECG monitor illustration

If you experience heart rhythm problems, or symptoms such as dizzy spells or blackouts, your doctor may suggest you have one of these tests.

1. Electrocardiogram (ECG)

Most GP surgeries can do an ECG to record your heart’s electrical activity. Wires connect sticky patches (electrodes) attached to your chest, and maybe arms and legs, to an ECG recorder.

2. Exercise ECG

Known as a stress test, exercise stress test or exercise tolerance test, it’s recorded while you’re on a treadmill or exercise bike. It helps doctors find out how severe your condition is or how well your heart works after surgery. It can show the level of exercise you should do as part of cardiac rehab. It can be used if you’ve been collapsing or blacking out, particularly while being active.

Find out more about what the exercise stress test involves.

3. Holter or ambulatory ECG monitoring

The ILR is about the size of a chewing gum packet or USB stick and its battery lasts up to three years

A continuously recording ECG, usually for 24 to 48 hours, to help diagnose the cause of symptoms, such as palpitations, which aren’t constant and rarely happen in the GP’s surgery. The test is safe and painless.

4. Cardiac event recorder

This small recording device is for those with infrequent palpitations or occasional collapses. When typical symptoms start, hold the device to your chest and activate it to record your heart rhythm, then contact your hospital. You’ll be shown how to use it and it’s not invasive or painful.

5. Implantable loop recorder (ILR)

This device records your heart’s electrical activity to find the cause of occasional symptoms, such as dizzy spells or blackouts. Doctors may use an ILR if other cardiac event recorders fail to reveal anything.

The ILR is about the size of a chewing gum packet or USB stick and its battery lasts up to three years. Inserting the ILR is a simple and quick procedure. After a local anaesthetic injection, a small cut (about 2cm) is made, allowing the device to be implanted under the skin on your chest.

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