What should you know about your first ECG machine test?

An ECG machine detects tiny electrical signals from the heart and displays them as waves on a tracing. A clinician looks at the rate, rhythm, timing, and shape of those waves alongside your symptoms and examination. The machine's printout is not a complete diagnosis by itself. A normal tracing at one moment may not capture an intermittent rhythm problem, while an unusual tracing can have several possible explanations.

Wear clothing that allows access to the chest, wrists, and ankles, and tell the clinician about medicines, implanted devices, and any skin irritation. Lie still, breathe normally, and avoid talking during the recording so muscle movement does not add interference. Electrodes may need clean, dry skin and sometimes a small area of hair is trimmed. The recording is generally brief, and you can return to normal activity unless your care team says otherwise.

Call emergency services for chest pressure, severe breathing difficulty, collapse, or sudden weakness with trouble speaking. Do not wait for an ECG appointment if these symptoms are happening. For palpitations, dizziness, or fainting that have stopped, arrange medical review and describe when they began, how long they lasted, and what you were doing.

Ask what prompted the ECG, when the tracing will be reviewed, whether another recording is needed, and how your symptoms affect its interpretation. Ask whether you should keep a diary of palpitations or avoid anything before further testing.