Heart monitor ECG machine: what to expect

An ECG machine receives signals from adhesive electrodes placed on the chest and limbs. The trace can show the timing of heartbeats, whether the rhythm is regular, and patterns that may suggest strain or reduced blood flow. A standard ECG captures a brief period, so an intermittent palpitation may not occur while it is being recorded. In that situation, a clinician may discuss longer monitoring or another test.

An ECG is a recording, not a diagnosis by itself. A clinician interprets it alongside your symptoms, examination, medicines, and medical history.

Wear clothing that allows access to the chest and lower limbs, and tell the clinician about any creams or skin irritation. You usually lie still and breathe normally while the electrodes record the trace. The procedure is brief and does not send electricity into your body. Do not stop prescribed medicines unless the clinician who arranged the test tells you to. If symptoms are intermittent, write down when they occur and bring that record to the appointment.

An ECG appointment should not replace emergency care. Call emergency services for chest pressure or pain, severe breathlessness, fainting, sudden confusion, or a new severe racing or irregular heartbeat. Contact the clinician who arranged the test if symptoms continue, worsen, or occur with dizziness, weakness, or reduced ability to exercise.

What question is this ECG intended to answer? Could a brief recording miss an intermittent symptom? Do I need longer monitoring or another test? When and how will the result be explained to me?