What should you know about an electrocardiogram tracing?

The tracing contains repeating wave patterns created as electrical signals move through the heart. A clinician reviews the heart rate, rhythm, timing between waves and shape of the pattern. One unusual-looking line may result from movement, poor electrode contact or a genuine change, so visual inspection alone is unreliable.

The recording represents the moment it was taken. A tracing can be normal between episodes, while a change during symptoms may be more informative. Your clinician may compare it with an older ECG or consider a portable monitor when symptoms are intermittent.

Keep the report and ask the interpreting clinician to explain unfamiliar terms in plain language. Share the symptoms, activity and medicines present when the tracing was recorded. Do not alter treatment based on a graph or automated machine comment without medical advice.

Seek emergency care for chest pressure, severe breathlessness, fainting, collapse or sudden neurological symptoms, regardless of what an earlier tracing showed. Seek prompt clinical advice for repeated palpitations, new dizziness or symptoms brought on by exertion.

Ask which features were assessed, whether the tracing explains your symptoms, and whether comparison, repeat recording or longer monitoring is appropriate.