Atrial Fibrillation
What is Atrial Fibrillation?
Atrial fibrillation is an arrhythmia, or abnormal heart rhythm, that originates in the upper chambers of the heart (atria). The heart has an electrical system which causes it to contract and relax. With atrial fibrillation, the electrical signals in the atria are fired in a very fast and uncontrolled manner. The atria quiver instead of contract. The electrical signals then arrive in the ventricles in an irregular pattern which causes a very fast, abnormal heart rate.
