Atrial fibrillation is one of the most common of all heart rhythm disorders.
This action is coordinated by the heart s electrical system. Normal electrical activation of the heart occurs in an orderly fashion. The impulse spreads through the atria, stimulating the atria to contract. The impulse then conducts to the ventricles, stimulating the ventricles to contract and pump blood out of the heart. When a patient s heartbeat changes from normal sinus rhythm to AF, the orderly activation of the atria is lost.