Atrial Fibrillation

Atrial fibrillation is a heart arrhythmia with abnormal signals that originate in the atria of the heart.

The electrical system of the heart is made up of several parts that communicate with one another to signal the heart muscle fibers when to contract. The SA node starts the signal causing the atria to contract. This signal travels through the AV node and on to the bundle of His, bundle branches, and Purkinje fibers causing the ventricles to contract. The flow of electrical signals is what produces a normal heartbeat.

In atrial fibrillation, disorganized electrical pulses that originate in the heart’s upper chambers cause the rhythm of the lower chambers to be fast and irregular. Because contractions are not coordinated as in a normal heartbeat; the heart does not pump blood effectively to the rest of the body.


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