What to expect from an ECG for atrial fibrillation

A clinician may look for an irregular rhythm, a fast or slow rate, and the pattern of electrical signals through the upper and lower chambers. If atrial fibrillation is happening during the recording, the ECG can help confirm it. A normal short recording does not rule out episodes that come and go, so a wearable monitor may be suggested.

The test does not send electricity into your body. Small adhesive electrodes are placed on the chest and sometimes the arms and legs; removal may briefly tug at body hair or irritate sensitive skin.

Wear clothing that allows access to your chest and tell the clinician about medicines, palpitations, dizziness, or a device such as a pacemaker. Rest quietly during the recording and avoid talking or moving so muscle activity does not interfere with the tracing.

Ask how and when you will receive the result. Further checks may include blood tests, an echocardiogram, or longer rhythm monitoring. Do not stop a prescribed medicine based on the ECG without discussing it with the prescriber.

Seek emergency help for chest pressure or pain, severe breathlessness, fainting, sudden weakness or numbness on one side, new trouble speaking, or confusion. These symptoms need urgent assessment whether or not an ECG has already been performed.

Ask whether the tracing captured atrial fibrillation, whether you need a longer monitor, what symptoms should prompt urgent help, and whether your medicines or activity need review.