Electrocardiogram (ECG)

An electrocardiogram is a quick, non-invasive recording of the heart's electrical activity.

Small adhesive sensors on the chest and limbs detect electrical signals as the heart beats. A machine turns those signals into a tracing that a clinician can review for rhythm, rate and patterns that may suggest strain or reduced blood supply.

You will usually lie still on an examination couch while a healthcare professional places electrode stickers on clean, dry skin. Hair may need to be moved or clipped where a sticker is needed. Wires connect the stickers to the recorder; they do not deliver electricity into your body. The recording itself takes only a short time.

An ECG is generally safe because it only records signals. Some people develop temporary skin redness where the stickers were placed. It gives a useful picture of the heart at the time of recording, but an ECG can be normal between episodes of an intermittent rhythm problem or chest symptoms. Clinicians interpret it alongside symptoms, examination findings and other tests when needed.

An unusual tracing does not by itself give a complete diagnosis. The clinician may compare it with an earlier ECG, repeat the test, arrange blood tests, heart imaging, or a longer recording that captures the heart during everyday activity. Urgent symptoms such as ongoing chest pressure, severe breathlessness, collapse or new weakness need prompt medical assessment.

Most ECGs need no special preparation. Wear clothing that allows easy access to the chest, and tell the clinician about medicines, a pacemaker or any skin reaction to adhesive products. Bring previous heart test results if you have them.

A clinician may request an ECG for palpitations, chest discomfort, breathlessness, fainting, an irregular pulse or before certain treatments. It can help assess conditions including Angina, Atrial Fibrillation, Heart Attack and Heart Failure, but it is one part of the clinical assessment rather than a standalone answer.

The clinician confirms your details and explains the test. You lie flat and relax your arms and legs. Electrode stickers are applied, the wires are attached, and you are asked not to talk or move briefly. Once the tracing is complete, the stickers are removed and you can get dressed.

There is no recovery period after a standard ECG. You can return to usual activities straight away. If stickers leave residue, wash the area gently. Timing for the result varies with the care setting; ask who will contact you and what to do if symptoms recur before then.

The main physical issue is mild, short-lived irritation from the adhesive. A normal tracing does not rule out every heart concern, especially when symptoms come and go. Seek urgent care for severe or persistent chest symptoms rather than waiting for a routine test appointment.

Depending on the question, a clinician may use an ECG Machine for an in-clinic recording, request a portable monitor, or arrange blood tests or imaging. A GP Consultation can help decide which assessment fits your symptoms and medical history.

Book through a GP or a clinic that can arrange cardiac assessment. Tell the service if you currently have chest pain, marked breathlessness, fainting or a fast irregular heartbeat, so they can advise on the appropriate urgency.