Atrial flutter is one of the more common abnormal heart rhythms (arrhythmias). It affects the upper heart chambers (atria). It's caused by an abnormal electrical circuit that makes the atria beat quickly and flutter instead of fully squeezing. It can result in fast heart rates and a heart that doesn't work as well as it should. This causes symptoms and increases the risk for stroke.
Normal electrical heart impulses are sent out from the sinus node (SA node) in the right atrium. This node controls the heart rate and timing of heartbeats. The electrical impulses travel through the heart muscle in the atria. This triggers the muscle to squeeze. In atrial flutter, an abnormal electrical circuit forms in the atria. This often happens after some types of heart surgery, heart muscle damage, or other heart changes. This new circuit takes over the heart rhythm and causes the abnormal fluttering.
Atrial flutter makes the heart work well in pumping blood. Some people have no or minor symptoms. If you do have symptoms, they can include: