Dartmouth-Hitchcock logo
Summer Flowers In This Section

Atrial Fibrillation/Arrhythmia

What is atrial fibrillation/arrhythmia?
What are the symptoms of atrial fibrillation/arrhythmia?
What causes atrial fibrillation/arrhythmia?
How is atrial fibrillation/arrhythmia diagnosed?
How can atrial fibrillation/arrhythmia be treated?

What is atrial fibrillation/arrhythmia?

Atrial fibrillation (often referred to as AFib or AF) is the most common kind of arrhythmia, or disturbance of the heart's rhythm. There are various kinds of arrhythmias; some make your heart beat too fast, some make it beat too slow, and some make it beat in an irregular rhythm. AFib is an irregular rhythm; the term "fibrillation" means rapid, quivering, uncoordinated movement.

AFib is sometimes a chronic, ongoing condition, but sometimes it happens sporadically, only every now and then. It occurs when your heart's electrical system, which controls your heartbeat, fails to properly coordinate the signals it sends to the heart's two upper chambers (the atriums) with the signals it send to the two lower chambers (the ventricles). This results in the atriums not being completely emptied of blood, and the ventricles not being completely filled. As a consequence, while too much blood pools in the atriums, not enough blood is available in the ventricles to supply the body's demand for oxygen and nutrients.

Some people with AFib feel no symptoms, but even symptomless forms of the condition can lead to heart failure, as a result of the ventricles' inability to fulfill the body's need for oxygen. In addition, the pooling of blood in the atriums can promote the formation of blood clots; if a clot breaks off and travels through your circulatory system, it can lodge in a vital organ and cause a stroke or heart attack.

Millions of people in the U.S. are affected by AFib, according to the National Institutes of Health, though it is hard to know exactly how many, since the condition is often symptomless. The risk of AFib rises with age, and its incidence is higher among men than women.

What are the symptoms of atrial fibrillation/arrhythmia?

Symptoms of a disease are indications that can be detected by the patient, such as pain or fatigue (while signs are indications that can be detected by a doctor, such as the results of a blood test or an X-ray). The symptoms of AFib include palpitations (a fluttering sensation in your heart); shortness of breath; weakness, especially upon exertion; chest pain; dizziness or fainting; fatigue or tiredness; and confusion.

What causes atrial fibrillation/arrhythmia?

image of heart's arteries AFib is caused by damage to the heart's electrical system. It can sometimes be hard to know exactly what led to the damage in a given situation. Such damage can be the result of a number of conditions, including high blood pressure (also known as hypertension); a narrowing of the arteries that supply the heart with blood (known as coronary artery disease or coronary heart disease); congestive heart failure; pericarditis, an inflammation of the sac around your heart; disorders of the aortic valve; or mitral valve prolapse.

The risk of suffering AFib is also elevated by conditions such as obesity, diabetes, and lung disease. Binge drinking also raises the risk of AFib, and even a small amount of alcohol can bring on the condition in some individuals. Caffeine and stress are also known to trigger AFib.

A number of additional factors have shown some association with the incidence of AFib, including sleep apnea, the use of high-dose steroids, and certain genetic characteristics.

How is atrial fibrillation/arrhythmia diagnosed?

Cases of symptomless AFib are sometimes identified when your doctor detects signs of the condition during a routine physical exam or after ordering, for some other reason, an electrocardiogram—a test that measures your heart's electrical activity.

If the presence of AFib is suspected, based either on such signs or on symptoms that you perceive, your doctor will likely start by conducting a thorough physical exam and taking a detailed medical and family history.

Certain diagnostic tests will likely be appropriate as well. The most useful test for diagnosing AFib is an electrocardiogram (also referred to as an ECG or EKG). Your doctor may also recommend a Holter monitor or event monitor test (these involve wearing a small, portable device that records your heart's electrical activity over the course of 24 to 48 hours), a stress test, an echocardiogram (an ultrasound image of your heart), a transesophageal echocardiogram (an ultrasound obtained by passing a thin tube down your throat and into your esophagus), a chest X-ray, or blood tests.

How can atrial fibrillation/arrhythmia be treated?

The treatment options for AFib vary according to how often the condition occurs, how severe your symptoms are, and what other health conditions you are affected by. The options include lifestyle changes (such as not smoking and staying active), medications (including some that reduce the likelihood of clot formation or that help control your heart's rhythm), and the implantation of a pacemaker.

In some cases, cardiac surgery may be the most appropriate option. The procedures that can restore your heart to a normal rhythm include cardiac ablation (which involves the use of either high-frequency radio waves or extreme cold to destroy the damaged portion of your heart's electrical system) and an operation known as a maze procedure (which involves making tiny cuts and burns in the atriums, to reorder the uncoordinated electrical signals).

Page reviewed on: Jun 26, 2015

Page reviewed by: Jock McCullough, MD

Contact Us