An electrocardiogram – or ECG – is a simple and useful test which records the rhythm and electrical activity of your heart. It can help detect problems with your heart rate or heart rhythm – called arrhythmias. It can help doctors tell if you’re having a heart attack or if you’ve had a heart attack in the past. Sometimes an ECG can indicate if your heart is enlarged or thickened.
Small sticky patches called electrodes are put on your arms, legs and chest. These are connected by wires to an ECG recording machine which picks up the electrical signals that make your heart beat. This electrical activity is recorded and printed onto paper.
24-hour ECG recording (also called Holter monitoring or ambulatory ECG monitoring) involves continuously recording your heart’s electrical activity for 24 to 48 hours. This can help diagnose symptoms – such as palpitations – which don’t happen all the time.
What are the risks?
An electrocardiogram is a safe procedure. There are no known complications associated with having it.