heart and blood vessel disorders
Atrial Fibrillation and Atrial Flutter
Introduction
Atrial fibrillation and atrial flutter are very fast electrical discharge patterns that make the atria (upper chambers of the heart) contract very rapidly, with some of the electrical impulses reaching the ventricles and sometimes causing them to contract faster and less efficiently than normal. These disorders often result from conditions that cause the atria to enlarge. Symptoms depend on how fast the ventricles contract and may include palpitations, weakness, dizziness or light-headedness, shortness of breath, and chest pain. Electrocardiography (ECG) confirms the diagnosis. Treatment includes drugs to slow the ventricles’ contractions and sometimes drugs or electrical shocks (cardioversion) to restore normal heart rhythm. (See also Overview of Abnormal Heart Rhythms .) Atrial fibrillation and atrial flutter are more common among older people and people who have a heart disorder. Atrial fibrillation is much more common than atrial flutter. Many people with atrial flutter also have episodes of atrial fibrillation. Atrial fibrillation and atrial flutter may come and go or be sustained. 