Atrial fibrillation

Atrial fibrillation is an irregular and often rapid heart rate that commonly causes poor blood flow to the body.

During atrial fibrillation, the heart's two upper chambers (the atria) beat chaotically and irregularly — out of coordination with the two lower chambers (the ventricles) of the heart. Atrial fibrillation symptoms often include heart palpitations, shortness of breath and weakness.

Episodes of atrial fibrillation can come and go, or you may develop atrial fibrillation that doesn't go away and may require treatment. Although atrial fibrillation itself usually isn't life-threatening, it is a serious medical condition that sometimes requires emergency treatment. It can lead to complications. Atrial fibrillation may lead to blood clots forming in the heart that may circulate to other organs and lead to blocked blood flow (ischemia).

Treatments for atrial fibrillation may include medications and other interventions to try to alter the heart's electrical system.

Symptoms Causes Risk factors Complications Prevention

A heart in atrial fibrillation doesn't beat efficiently. It may not be able to pump enough blood out to your body with each heartbeat.

Some people with atrial fibrillation have no symptoms and are unaware of their condition until it's discovered during a physical examination. Those who do have atrial fibrillation symptoms may experience signs and symptoms such as:

  • Palpitations, which are sensations of a racing, uncomfortable, irregular heartbeat or a flip-flopping in your chest
  • Weakness
  • Reduced ability to exercise
  • Fatigue
  • Lightheadedness
  • Dizziness
  • Confusion
  • Shortness of breath
  • Chest pain

Atrial fibrillation may be:

  • Occasional. In this case it's called paroxysmal (par-ok-SIZ-mul) atrial fibrillation. You may have symptoms that come and go, lasting for a few minutes to hours and then stopping on their own.
  • Persistent. With this type of atrial fibrillation, your heart rhythm doesn't go back to normal on its own. If you have persistent atrial fibrillation, you'll need treatment such as an electrical shock or medications in order to restore your heart rhythm.
  • Permanent. In this type of atrial fibrillation, the abnormal heart rhythm can't be restored. You'll have atrial fibrillation permanently, and you'll often require medications to control your heart rate. Most people with permanent atrial fibrillation will require blood thinners to prevent blood clots.

When to see a doctor

If you have any symptoms of atrial fibrillation, make an appointment with your doctor. Your doctor may order an electrocardiogram to determine if your symptoms are related to atrial fibrillation or another heart rhythm disorder (arrhythmia).

If you have chest pain, seek emergency medical assistance immediately. Chest pain could signal that you're having a heart attack.

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