These signals are recorded by a machine and the doctor will review them to see if they’re unusual.
A heart specialist (cardiologist) may ask you to have an ECG if they think you might have a problem with your heart.
The test can be carried out by a trained healthcare professional at a hospital or clinic.
Despite having a similar name, an ECG isn’t the same as an echocardiogram. An echocardiogram involves gel to the chest and an ultrasound scan of the heart, and is usually done in hospital.
When an ECG is used
An ECG is often used to help diagnose and check conditions affecting the heart.
It can be used to investigate symptoms of a possible heart problem. These could be chest pains, palpitations, dizziness and shortness of breath. Palpitations are suddenly noticeable heartbeats.
An ECG can help detect:
- • Arrhythmias – where the heart beats too slowly, too quickly, or irregularly
- • Coronary heart disease – where the heart’s blood supply is blocked or interrupted by a build-up of fatty substances
- • Heart attacks – where the supply of blood to the heart is suddenly blocked
- • Cardiomyopathy – where the heart walls become thickened or enlarged
A series of ECGs can also be taken to check a person already diagnosed with a heart condition. It’s also used to check on someone taking medication that is known to affect the heart.
How an ECG is carried out
Small, sticky sensors called electrodes are attached to your arms, legs and chest. These are connected by wires to an ECG recording machine.
You do not need to do anything special to prepare for the test. You can eat and drink as normal beforehand.
Before the electrodes are attached, you’ll usually need to remove your upper clothing. Your chest may need to be shaved or cleaned. Once the electrodes are in place, you may be offered a hospital gown to cover yourself.
The test itself usually only lasts a few minutes. You should be able to go home soon afterwards or return to the ward if you’re already staying in hospital.
Getting your results of your ECG
An ECG will show your heart rhythm and electrical activity as a graph displayed electronically or printed on paper.
Risks and side effects of an ECG
An ECG is a quick, safe and painless test. No electricity is put into your body while it is carried out.
There may be some slight discomfort when the electrodes are removed from your skin. It will be like removing a sticking plaster. Some people may develop a mild rash where the electrodes were attached. This normally settles with time