An electrocardiogram is a diagnostic test that measures the electrical activity of the heart.

The Heart’s Electrical System

An electrocardiogram, also called an ECG, is a quick, painless test that measures the heart’s electrical activity and records any disturbances in heart rhythm. 

An ECG or electrocardiogram is a very simple and straightforward test which is used to check your heart’s electrical activity and rhythm.

To do this a doctor will attach sensors to your skin which detect electrical signals each time your heart beats. A machine records these signals and produces a graph for the doctor to interpret.

If you have been to see one of the London Cardiac and Vascular Cardiologists (Dr Byrne, Dr Melikian or Dr Dworakowski) they may have suggested an ECG for you to check for abnormal or unusual heart rhythms.

It’s important to note that an ECG, although the name sounds similar, is not the same as an echocardiogram (a heart scan).

Why would I need to have an ECG?

An ECG is a really useful tool, often used alongside other tests, to help diagnose and monitor conditions which affect the heart. An ECG is very helpful for investigating what could be the cause of symptoms such as chest pain, palpitations, dizziness and shortness of breath. Often an ECG can show arrhythmias, coronary heart disease, heart attacks and cardiomyopathy. Sometimes a patient may have a series over ECGs over time to monitor a heart condition which has already been diagnosed.

What happens during an ECG?

Although there are a few ways to carry out an ECG. Usually, a number of small, sticky sensors (electrodes) are attached to your arms, legs and chest. These wires are linked to an ECG recording machine which produces a graph representing the heart rhythm. There isn’t anything you need to do as a patient before the test, you can eat and drink as normal. Your arms and chest usually need to be bare to attach the electrodes so you’re often given a hospital gown to cover up with once they are in place. The test only lasts a couple of minutes and most of the time you can go home straight afterwards.

Are there different types of ECG?

There are three main types of ECG:

  • Resting ECG – for this one you will usually be lying down
  • Stress ECG – for this you will be asked to use an exercise bike or treadmill whilst wearing the electrodes
  • Ambulatory ECG – the electrodes are attached to a small portable recording machine so you can wear it for 24-48 hours to look at heart rhythms over time.

How do I get the results?

We will usually as you to come back to the clinic to discuss your results with your cardiologist a few days after your test. Here we will discuss what the test showed and what the plan might be going forwards. 

What are the risks of an ECG?

An ECG is safe, quick and painless. No electricity is put through the body during the test. The only discomfort might be when the electrodes are removed – a bit like taking a plaster off. During an exercise ECG you are closely monitored and the test can be stopped immediately if you feel at all unwell.

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Healthy Living

Keeping your heart healthy involves maintaining an active lifestyle and identifying any potentially dangerous heart problems before they become more severe.