ECG machine: what to know

An ECG machine receives signals from adhesive electrodes placed on the chest and limbs. It displays and prints a tracing that can show the timing and pattern of each heartbeat. The test may help a clinician investigate palpitations, chest discomfort, breathlessness, dizziness, or an abnormal pulse. An ECG is a short snapshot, so a normal tracing does not explain every possible symptom; the result is interpreted alongside your history, examination, and other tests.

Wear clothing that allows access to the chest and lower limbs, and tell the healthcare professional about medicines, implanted devices, or skin reactions to adhesives. You usually rest quietly while the electrodes are attached, then remain still during the recording. The adhesive may feel cool when removed, and temporary skin irritation can occur. Follow the appointment instructions and mention if movement, shivering, or a fast heartbeat happens during the test.

An ECG appointment should not delay emergency help for severe or persistent chest pain, fainting, marked breathlessness, new weakness on one side, or a racing heartbeat with dizziness. Call emergency services for symptoms that are sudden, severe, or worsening. If you have recurrent palpitations or unexplained dizziness without emergency signs, arrange a clinical review so the timing of symptoms can guide further monitoring.

Ask why the ECG is being requested, whether you need a resting or longer recording, when the result will be reviewed, and what symptoms should prompt urgent help.