Atrial flutter, also called abnormal heart rhythm, is a type of atrial arrhythmia in which a rapid, circular impulse travels through the atrium (upper chamber of the heart). The impulse usually takes the same path over and over again, like a car traveling around a race track. The rate of the atrium is usually 200 to 300 beats per minute. The electrical signals then travels from the upper chambers (atria) to the lower chambers (ventricles) via a connector called the A-V node. The rate of the heart beat is the rate of the ventricles. Usually the rate of the ventricular beat is between 75 and 150 beats per minute.
Atrial flutter can occur once in a while or on an ongoing basis.