Atrial Fibrillation

Untreated atrial fibrillation can lead to stroke and heart failure. Medications can help prevent blood clots and control heart rate so patients can live normal, active lives.

Atrial Fibrillation Overview

Reviewed: July 22, 2014

Atrial fibrillation (AF) is a common heart arrhythmia that results from the two upper chambers of the heart (atria) beat rapidly and unpredictably, producing an irregular heartbeat. Untreated atrial fibrillation puts patients at increased risk for stroke and heart failure.

The most common symptom of AF is a quivering or fluttering heartbeat. Other symptoms include palpitations, shortness of breath, dizziness/light headedness, and fatigue, among others. Some people may have AF but present with no symptoms.

Atrial fibrillation results from rapid and disorganized travel of cardiac electrical signals through the heart. Damage to the heart's electrical system usually occurs from conditions that affect heart health, most commonly high blood pressure and coronary artery disease. AF is more common in men compared to other races and women. Risks also increase with advancing age.

Treatment for atrial fibrillation aims to prevent the formation of blood clots and control heart rate and rhythm. Blood clots are prevented by blood thinning medications such as warfarin (Coumadin), dabigatran, heparin, or aspirin. Rate control may be accomplished through beta blockers such as metoprolol and atenolol, calcium channel blockers such as diltiazem and verapamil, and digitalis (digoxin). Rhythm control treatment usually occurs in a hospital setting, so patients can be closely monitored. Medications include amiodarone, sotalol, flecainide, propafenone, dofetilide, and ibutilide. Electrical cardioversion and catheter ablation are electrical and surgical procedures, respectively, that can restore regular rate and rhythm.

Atrial Fibrillation Symptoms

Atrial fibrillation (AF) usually causes the heart's lower chambers, the ventricles, to contract faster than normal.

When this happens, the ventricles can't completely fill with blood. Thus, they may not be able to pump enough blood to the lungs and body.

The most common symptom is a quivering or fluttering heartbeat. Other symptoms may include:

  • Palpitations -an abnormal rapid heartbeat
  • Shortness of breath
  • Anxiety
  • Weakness
  • Dizziness or fainting
  • Light headedness
  • Fatigue
  • Confusion
  • Trouble with everyday exercises or activities
  • Pain, pressure, tightness, or discomfort in your chest
  • Increased urination (using the bathroom more often)

Atrial Fibrillation Causes

Atrial fibrillation (AF) occurs if the heart's electrical signals travel through the heart in an abnormal way. Instead, the electrical signals are rapid and disorganized.

Damage to the heart's electrical system causes AF. The damage is usually caused by other conditions that affect the health of the heart, such as high blood pressure and coronary heart disease.

Risk factors:

Atrial fibrillation (AF) affects millions of people, and the number is rising.

  • Gender. Men are more likely than women to have the condition. 
  • Race. In the United States, AF is more common among Whites than African Americans or Hispanic Americans.
  • Age. The risk of AF increases as you age. This is mostly because your risk for heart disease and other conditions that can cause AF also increases as you age. In addition, inflammation also is thought to play a role in causing AF. About half of the people who have AF are younger than 75. (AF is uncommon in children)

However, sometimes, the cause of AF is unknown.

Risk Factors:

  • High blood pressure
  • Coronary heart disease (CHD)/ Underlying heart disease
  • Post heart surgery
  • Heart failure
  • Drinking alcohol
  • Family history
  • Other chronic conditions such as thyroid problems, diabetes, and asthma
  • Rheumatic heart disease
  • Structural heart defects, such as mitral valve prolapse
  • Pericarditis- a condition in which the membrane, or sac, around your heart is inflamed)
  • Congenital heart defects
  • Sick sinus syndrome (a condition in which the heart's electrical signals do not fire properly and the heart rate slows down; sometimes the heart will switch back and forth between a slow rate and a fast rate)
  • Have just had surgery
  • Sleep apnea
  • Athletes 


Atrial Fibrillation Diagnosis

Atrial fibrillation (AF) is diagnosed based on your medical and family history, a physical exam, an electrocardiogram (EKG), and other tests.

If you have AF, your doctor will need to determine the cause. This will help him or her plan the best way to treat the condition.

Medical and Family Histories

Your doctor will usually ask questions about your:

  • Signs and symptoms
  • Medical history
  • Family's medical history
  • Health habits (smoking, and alcohol, and caffeine use)

Physical Exam

Your doctor will do a complete cardiac exam which may include:

  • listening to the rate and rhythm of your heartbeat
  • taking your pulse and blood pressure reading
  • checking for any signs of heart muscle or heart valve problems
  • listening to your lungs to check for signs of heart failure
  • checking for swelling in your legs or feet
  • checking for an enlarged thyroid gland or other signs of hyperthyroidism (too much thyroid hormone)

Diagnostic Tests and Procedures


An EKG records the heart's electrical activity and is the most useful test for diagnosing AF. An EKG shows how fast your heart is beating and monitors the. It also records the strength and timing of electrical signals as they pass through your heart.

Since a standard EKG records the heartbeat for a few seconds, it does not have the ability to detect AF that doesn't happen during the exam. As a result, your doctor may ask you to wear a portable EKG monitor that can obtain a recording of your heartbeat for a longer period of time.

The two most common types of portable EKGs are Holter and event monitors.

Holter and Event Monitors

  • A Holter monitor records the heart's electrical activity for a full 24- or 48-hour period. You wear the Holter monitor while doing your normal daily activities.
  • Like a Holter monitor, an event monitor is worn while doing your normal activities. However, an event monitor only records your heart's electrical activity at certain times while wearing it.

You can wear an event monitor for weeks or until symptoms occur.

Mobile cardiac monitoring- A mobile cardiac monitor is worn for up to 30 days.

Stress Test

Some heart problems are easier to diagnose when your heart is working hard and beating fast. During stress testing, you will need to exercise to make your heart work hard and beat fast. You may be given medicine to make your heart work hard and beat fast, if you can't exercise.


Echocardiography (echo) uses sound waves to create a moving picture of your heart to show how well your heart chambers and valves are working.

Echo also can identify areas of poor blood flow to the heart as well as identify previous injury to the heart muscle.

Sometimes it is called transthoracic echocardiography.

Transesophageal Echocardiography

Transesophageal echo, or TEE, uses sound waves to take pictures of your heart through the esophagus to detect blood clots.

Chest X Ray

A chest x ray creates pictures of the structures in your chest, such as your heart and lungs. This test can identify complications associated with AF, such as fluid buildup in the lungs.

Blood Tests

Your doctor may order blood tests to check the level of thyroid hormone in your body and the balance of your body's electrolytes.

Living With Atrial Fibrillation

People who have atrial fibrillation (AF) even permanent AF can live normal, active lives. If you have AF, ongoing medical care is important.

  • Keep all your medical appointments. Tell your doctor about all the medications you take including over-the-counter medications and supplements
    • Follow your doctor's instructions for taking medicines.
    • Taking caution when taking over-the-counter medicines, nutritional supplements, and cold and allergy medicines. Some of these products contain stimulants and can trigger rapid heart rhythms.
    • Some over-the-counter medicines can have harmful interactions with heart rhythm medicines.
  • Tell your doctor if your medicines are causing side effects, if your symptoms are getting worse, or if you have new symptoms.
  • If you are taking blood thinning medicines, your doctor will order routine blood tests to check how the medicines are working.
  • If you are taking warfarin (Coumadin), ask your doctor about your diet. Foods that contain vitamin K, found in green leafy vegetables, can affect how well warfarin (Coumadin) works.
  • Ask your doctor about physical activity, weight control, and alcohol use.

To reduce the risk of complications associated with atrial fibrillation, try to:

  • Get regular exercise
  • Eat a heart-healthy diet, low in saturated fats, trans fats, and cholesterol, low in salt
  • Manage high blood pressure
  • Avoid excessive amounts of alcohol and caffeine
  • Avoid stimulants which can increase your heart rate
  • Avoid smoking
  • Control cholesterol
  • Maintain a healthy weight
  • Reduce stress

Your doctor may prescribe medicines to treat an overactive thyroid, lower high blood pressure, or manage high blood cholesterol.

Atrial fibrillation can increase the risk for stroke. The warning signs of a stroke are listed below:

  • Face Drooping.
  • Arm Weakness in one side
  • Slurred speech

If the person shows any of these symptoms, even if the symptoms go away, call 9-1-1 and get them to the hospital immediately.

Atrial Fibrillation Treatments

Treatment for atrial fibrillation (AF) depends on how often you have symptoms, how severe they are, and whether you already have heart disease. General treatment options include medicines, medical procedures, and lifestyle changes.

Goals of Treatment

The goals of treating AF include:

  • Prevent blood clots formation
  • Rate control: Controlling how many times a minute the ventricles contract. Rate control is important because it allows the ventricles enough time to completely fill with blood.
  • Rhythm control. Rhythm control allows the atria and ventricles to work together to pump blood to the body efficiently.
  • Treat any underlying disorder that's causing or raising the risk of AF such as hyperthyroidism (too much thyroid hormone).

In some cases, treatment is not needed. In some people who have AF for the first time, doctors may choose to use an electrical procedure or medicine to restore a normal heart rhythm.

Repeat episodes of AF can cause changes to the heart's electrical system and lead to persistent or permanent AF. As a result, those who have persistent or permanent AF, need treatment to control their heart rate and prevent complications.


Blood Clot Prevention

AF increases the risk for stroke. Blood pools in the atria and can cause a blood clot to form. If the clot breaks off and travels to the brain, it can cause a stroke.

Preventing blood clots from forming is probably the most important part of treating AF. Your doctor can prescribe blood thinning medicines such as warfarin (Coumadin), dabigatran, heparin, or aspirin. Your doctor will order routine blood tests to monitor how effective your medication is.

Rate Control

Doctors can prescribe medicines to slow down the rate at which the ventricles are beating. These medicines help bring the heart rate to a normal level. Rate control is the recommended treatment for most patients who have AF, even though an abnormal heart rhythm continues. If heart rates are well controlled, most people feel better and can function well.

Your doctor can prescribe beta blockers, such as metoprolol and atenolol, calcium channel blockers such as diltiazem and verapamil, and digitalis (digoxin) to control the heart rate.

Rhythm Control

For those people who are not responding to treatment for rate control, treatment for restoring and maintaining a normal heart rhythm is recommended. This treatment also may be used for those who have only recently started having AF.

Rhythm control treatment usually occurs in a hospital setting, so patients can be closely monitored.

  • The longer you have AF, the less likely it is for a normal heart rhythm to be restored. (This is especially true for people who have had AF for 6 months or more)

Medicines. Medicines used to control the heart rhythm include amiodarone, sotalol, flecainide, propafenone, dofetilide, and ibutilide. In some cases, other medicines such as quinidine, procainamide, and disopyramide, can be used.


  • Electrical cardioversion. Doctors can use several procedures such as electrical cardioversion to treat a fast or irregular heartbeat. During this procedure, low energy shocks are given to your heart to trigger a normal rhythm.
  • Catheter ablation. Catheter ablation may be used to restore a normal heart rhythm if medicines or electrical cardioversion don't work. For this procedure, a wire is inserted through a vein in the leg or arm up to the heart.
    • in some cases, doctors use catheter ablation to destroy the atrioventricular (AV) node to help maintain a normal heart rhythm.
  • Maze surgery. Your doctor can also perform a maze surgery. The surgeon makes small cuts or burns in the atria which prevent disorganized electrical signals from spreading. This procedure requires open-heart surgery, so it will not be done unless the person requires heart surgery for another reason.

Atrial Fibrillation Prognosis

People who have AF can live normal, active lives. For some people, treatment can restore normal heart rhythms.

For people who have permanent AF, treatment can help manage symptoms and prevent complications.

AF has two major complications—stroke and heart failure.


Atrial fibrillation is a major risk factor for stroke, making a person five times more likely to have a stroke.

During AF, the heart's upper chambers, the atria, don't pump all of their blood to the ventricles. As a result, some blood may pool in the atria and cause a blood clot to form. If the clot breaks off and travels to the brain, it can cause a stroke.

Your doctor will probably prescribe you blood-thinning medicines such as anticoagulants. These medications can help prevent blood clots and can reduce the risk of first stroke in AF patients by 68 percent.

Heart Failure

Heart failure can happen with AF, because the ventricles are beating very fast yet can't completely fill with blood. Heart failure occurs when the heart can't pump enough blood to the lungs and body.

Fatigue and shortness of breath are common symptoms of heart failure which is due to a buildup of fluid in the lungs. Fluid also can build up in the feet, ankles, and legs, causing weight gain.

Lifestyle changes, medicines, and procedures or surgery (rarely, a mechanical heart pump or heart transplant) are the main treatments for heart failure.