Atrial fibrillation on an ECG

An electrocardiogram uses skin electrodes to record electrical signals from different views of the heart. In atrial fibrillation, the usual organised atrial wave is absent and the intervals between lower-chamber beats are irregular. The tracing also shows the ventricular rate and may reveal conduction changes or clues to other heart problems.

The test records only the period when it is connected. If episodes come and go, a clinic ECG taken between symptoms may look normal. A portable monitor worn for longer can capture the rhythm during palpitations, breathlessness or dizziness and link the electrical finding with the symptom diary.

A standard ECG is quick and does not send electricity into the body. Tell the clinician about current symptoms, when they began, medicines and supplements, previous heart conditions and any wearable tracings. Skin products or dense chest hair can sometimes interfere with electrode contact, so staff may prepare small areas of skin.

A confirmed tracing starts a broader assessment rather than deciding treatment by itself. Care may include controlling rate, considering rhythm restoration, looking for triggers and evaluating clot-related stroke risk. Blood tests and heart imaging may be recommended according to the clinical picture. Continue prescribed medicine unless the treating clinician gives different instructions.

Seek emergency care for palpitations accompanied by chest pain, severe breathlessness, fainting or marked confusion. Sudden facial weakness, weakness on one side, speech trouble, vision loss or a severe new coordination problem can be signs of stroke and require an immediate emergency response.

Arrange a prompt appointment for recurring episodes, unexplained dizziness, declining exercise tolerance or a wearable alert that repeatedly reports an irregular rhythm. Save available tracings and note symptom times, but do not delay care while trying to capture a perfect recording.

Ask whether atrial fibrillation was present throughout the recording, what the ventricular rate means for you, and whether any other electrical changes appeared. Discuss whether longer monitoring, an echocardiogram or blood tests are appropriate and how the result affects rate control, rhythm control and anticoagulation decisions.