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Whenever you press your palm against your chest, you can feel your heart beating. Those beats are your heart pumping blood into and out of its chambers and to the rest of your body. First, the upper two chambers of the heart (atria) contract to receive blood. Then, the lower two chambers (ventricles) contract to send blood out to the body.

In slightly more than 2 million Americans, the electrical system that controls the heart's pumping mechanism doesn't work correctly. Instead of contracting normally, the two upper chambers of the heart flutter randomly, in an uncoordinated way. This leads to an irregular heartbeat (arrhythmia) called atrial fibrillation, or AFib.

Atrial fibrillation is more than just an annoyance. It can be very serious. Because blood doesn't pump efficiently from the atria to the ventricles, it can pool and form clots. If one of these clots breaks off and gets stuck in an artery in your brain, you can have a stroke. People who have atrial fibrillation are five times more likely to have a stroke than those who don't have the condition. AFib also makes your heart a less efficient pumper, which can raise your risk for heart failure.

Am I at Risk for Atrial Fibrillation?

You could be at risk for AFib if you are over age 60 or you have one of the following conditions:

  • Heart disease due to high blood pressure
  • Heart valve disease
  • Heart muscle disease (cardiomyopathy)
  • Heart defect from birth (congenital heart defect)
  • Long-term lung disease (such as COPD)
  • Heart failure
  • Past heart surgery
  • Overactive thyroid gland
  • Sleep apnea

Certain medicines (including digitalis, adenosine, and theophylline) can raise the risk of AFib. Sometimes, atrial fibrillation may be linked to heavy alcohol, caffeine, or drug use, as well as to infections or inherited factors.

Learning to Recognize AFib Symptoms

If you have one or more of the risk factors listed above, watch out for these AFib symptoms:

  • A feeling like your heart is racing or fluttering in your chest (palpitations)
  • Fatigue or weakness
  • Dizziness
  • Chest pain or pressure
  • Shortness of breath

Sometimes AFib doesn't cause any symptoms, which is why it's important to see your doctor regularly if you're at risk for this condition.

Life With Atrial Fibrillation

Tips and facts to help you
live your best with atrial
fibrillation.
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Discover what happens during atrial fibrillation and what your doctor can do to manage it.

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