What is Atrial Fibrillation (AF)?
- Atrial Fibrillation (AF or A Fib) is a relatively common heart disorder. AF is an irregular, rapid contraction of the atria.
- The human heart is made up of four chambers (two atria and two ventricles) that normally work together to pump the blood throughout the body.
- In AF, however, the atria beat out of rhythm with the rest of the heart. In fact, the atria may beat as many as 400 to 600 times a minute during AF, compared with a normal 60 to 100 times a minute.
- These irregular, rapid contractions make it difficult for the left atrium to empty blood into the left ventricle, which then pumps the blood to the body.

- AF can occur in otherwise healthy individuals. But, in most cases, AF is associated with underlying heart disease or, occasionally, with thyroid disorders.
- Although some patients with AF experience no symptoms, many experience a wide variety of symptoms, including palpitations, fatigue, dizziness, shortness of breath, and chest pain. So it is important to recognize the symptoms of AF so you can discuss them with your doctor.

