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Do you ever feel like your heart is racing or fluttering, even when you're at rest? It’s often an isolated event for those with a healthy heart. But sometimes these symptoms can be caused by an arrhythmia or heart rhythm disorder.

One common arrhythmia is called atrial fibrillation or AFib. During AFib, the atria -- the smaller chambers that normally pump blood into the larger ventricles -- quiver rapidlyand erratically. This causes the atria not to squeeze blood effectively into the ventricles. It typically results in a rapid and irregular heartbeat.

“Normally, one’s own pacemaker beats at rates between 60 and 100 beats per minute at rest. In contrast, during atrial fibrillation, the atria are being activated at rates in excess of 400 beats per minute in a chaotic electrical pattern,” says Richard L. Page, MD, chair in the department of medicine at the University of Wisconsin School of Medicine & Public Health in Madison.

Atrial fibrillation symptoms can include:

  • Heart palpitations (feeling that your heart is racing or fluttering)
  • Awareness that the heart is beating
  • Chest pain, pressure, or discomfort
  • Abdominal pain
  • Shortness of breath
  • Lightheadedness
  • Fatigue or lack of energy
  • Exercise intolerance

Atrial fibrillation may happen occasionally with symptoms that come and go, last for a few minutes to hours, and then stop on its own. With chronic atrial fibrillation, the arrhythmia is always present.

AFib Is More Common in Older Adults

Atrial fibrillation is more common as adults get older. Approximately 11% of people over 80 years of ageare affected by this arrhythmia.

In many cases, people with atrial fibrillation don't have any symptoms. It’s not uncommon for atrial fibrillation to be discovered as the cause after a first stroke for older adults, Page says.

There is a higher risk for stroke if diagnosed with AFib, especially with factors such as heart valve disease, heart failure, diabetes, and hypertension. Blood clots can form in the atria from atrial fibrillation. This can lead to a stroke when the clot leaves the heart and travels to the brain.

Life With Atrial Fibrillation

Tips and facts to help you
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