Atrial Flutter

Both conditions are types of supraventricular (above the ventricles) tachycardia (rapid heart beat). In AFL, the upper chambers (atria) of the heart beat too fast, which results in atrial muscle contractions that are faster than and out of sync with the lower chamber (ventricles).

Sometimes, the muscle of the atria contracts, or beats, as fast as 250 to 400 beats per minute. Almost always, however, the pulse (determined by the bottom ventricles) is less rapid. This is because the heart has a built-in “gate” or “filter” (the atrioventricular (AV) node) that controls how many of these fast electrical impulses get through from the atria to the ventricles. Atrial flutter is caused by a single electrical wave (“short circuit”) that usually circulates very rapidly around the right atrium (upper chamber) of the heart in the exact same pattern over and over.