Atrial flutter is a type of supraventricular tachycardia, which is a condition that causes an abnormally fast heart rate. It is characterized by an abnormally rapid and regular contraction of the atria, which is the two upper chambers of the heart.
Atrial flutter is caused by a re-entry circuit in the atria, which is a sort of short-circuit that causes the heart to beat too quickly. When this happens, the heart's normal electrical signal is disrupted, resulting in the atria beating much more rapidly than normal. The most common type of atrial flutter has a rate between 250 and 350 beats per minute.
Atrial flutter can be dangerous because it can lead to an inadequate supply of blood to the rest of the body. It can also cause the heart's lower chambers, called the ventricles, to become overworked, leading to a potentially life-threatening condition known as ventricular fibrillation.
Atrial flutter is usually treated with medications and/or procedures such as electrical cardioversion, ablation, and pacemaker placement. The goal of treatment is to restore the heart's normal rhythm and to prevent future episodes of atrial flutter.