Alex Ehsan, MD, PhD · Medical search

Atrial Fibrillation

Educational information. Individual clinical review of this presentation by Dr. Ehsan is not yet documented. It does not replace personal medical evaluation.

Source: MedlinePlus, National Library of Medicine. Read the original source

MedlinePlus data edition September 26, 2026. Imported September 27, 2026. These dates do not indicate a new clinical review of the article.

What is atrial fibrillation (AFib)?

Atrial fibrillation, also known as AFib or AF, is one of the most common types of arrhythmias. Arrhythmias are problems with the rate or rhythm of your heartbeat. They can cause your heart to beat too slowly, too fast, or in an irregular way.

If you have AFib, your heart beats irregularly and sometimes much faster than normal. Also, your heart's upper and lower chambers do not work together as they should. When this happens, the lower chambers do not fill completely or pump enough blood to your lungs and body. This can cause symptoms such as dizziness, fatigue, and a pounding heartbeat.

AFib may happen in brief episodes, or it may be a permanent condition. It's very important to treat it, since AFib can put you at risk for stroke and other heart conditions.

What causes atrial fibrillation (AFib)?

AFib is most often caused by changes to the heart's tissue or the electrical signaling that helps the heartbeat. These changes can happen due to different conditions and factors, such as high blood pressure, coronary artery disease, congenital heart defects, infections, and aging. Sometimes the cause is unknown.

Who is more likely to develop atrial fibrillation (AFib)?

Anyone can develop AFib, but there are certain things that raise your risk for it:

What are the symptoms of atrial fibrillation (AFib)?

Some people who have AFib don't have any symptoms and don't know they have it. If you do have symptoms, you may only notice them once in a while. Or you may have symptoms that are more frequent. And in some cases, the symptoms might be severe. If you have heart disease, you are more likely to notice your symptoms. And those symptoms could get worse if your heart disease gets worse.

The symptoms of AFib can include:

What other problems can AFib cause?

If AFib is not treated, it can lead to serious health problems (complications) such as:

To help prevent these problems, it's important to contact your health care provider if you are having symptoms. If you do have AFib, the sooner you are diagnosed and treated, the better.

How is atrial fibrillation (AFib) diagnosed?

To find out if you have AFib, your provider:

What are the treatments for atrial fibrillation (AFib)?

The treatments for AFib may include:

Can atrial fibrillation (AFib) be prevented?

There are steps you can take to help lower your risk of atrial fibrillation, such as:

NIH: National Heart, Lung, and Blood Institute

Questions for your care team

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For a life-threatening emergency, call 911 in the U.S. or your local emergency number.

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