How is AFib Diagnosed?
There are several ways to diagnose atrial fibrillation. Sometimes, health care professionals find evidence of AFib while treating people for other conditions or during surgery. But more often, your health care professional will start with tests to monitor your heart’s rhythm. If you wear a smartwatch or other device with a wearable heart rhythm monitor and it alerts you to an abnormal rhythm, be sure to let your health care professional know. This information can be a helpful part of your diagnosis.
Electrocardiogram (ECG OR EKG)
An electrocardiogram measures the heart’s electrical activity, which controls heart rhythm. Electricity is not sent into your body. This test usually happens in a doctor’s office and takes only a few minutes.
For this noninvasive test, a technician will put sticky plastic sensors on your chest and limbs. The sensors have wires attached to a computer. They pick up your heart’s electrical signals and send the information to the computer, which turns the signals into a graph. Health care professionals review the graph for any abnormal rhythms that might indicate AFib.
EKG strip showing a normal heartbeat
Learn more about electrocardiograms.
Heart Rhythm Monitor
A health care professional may send you home with a wearable heart rhythm monitor, sometimes called a Holter monitor, that can track your heart’s electrical activity for a longer period.The device can monitor and detect abnormal rhythms that come and go, which may not show up during the short ECG test. You may be instructed to wear it for 24 or 48 hours or longer.
A Holter monitor has three or four sensors that attach to your chest and connect to the recording device worn around your neck or on a belt. During the test, you may also need to write down details about your physical activity and sleep. Your health care professional will download the information the device collects and review it for irregularities.
Learn more about Holter monitors.
Medical History
Health care professionals will also consider your risk factors for AFib when they make a diagnosis. They may review your medical records for existing health conditions. Things they may consider include:
- Older age
- Underlying heart issues
- High blood pressure
- Obesity
- Type 2 diabetes
- Sleep apnea
- Alcohol use
- Smoking
