Topic Overview

What is atrial fibrillation?

Atrial fibrillation (say "AY-tree-uhl fih-bruh-LAY-shun") is the most common type of irregular heartbeat (arrhythmia).

Normally, the heart beats in a strong, steady rhythm. In atrial fibrillation, a problem with the heart's electrical system causes the two upper parts of the heart, the atria, to quiver, or fibrillate.

The quivering upsets the normal rhythm between the atria and the lower parts of the heart, the ventricles. And the ventricles may beat fast and without a regular rhythm.

This is dangerous because if the heartbeat isn't strong and steady, blood can collect, or pool, in the atria. And pooled blood is more likely to form clots. Clots can travel to the brain, block blood flow, and cause a stroke.

Atrial fibrillation can also lead to heart failure.

What causes atrial fibrillation?

Conditions that damage or strain the heart commonly cause atrial fibrillation. These include:

• High blood pressure.
• Coronary artery disease.
• Heart attack.
• Heart valve disease.

Other possible causes include:

• Other medical problems, such as heart failure, lung disease, pneumonia, or a high thyroid level.
• Heart surgery.
• Heavy alcohol use. This includes having more than 3 drinks a day over many years as well as drinking a large amount of alcohol at one time (binge drinking).

What are the symptoms?

Symptoms may include:

• Feeling dizzy or light-headed.
• Feeling out of breath.
• Feeling weak and tired.
• Feeling like the heart is fluttering, racing, or pounding (palpitations).
• Feeling like the heart is beating unevenly.
• Having chest pain (angina).
• Fainting.
• Sweating.
• Feeling anxious.

Sometimes atrial fibrillation doesn't cause obvious symptoms.

If you have symptoms, see your doctor. Finding and treating atrial fibrillation right away can help you avoid serious problems.

How is atrial fibrillation diagnosed?

The doctor will ask questions about your past health, do a physical examination, and order tests.

The best way to find out if you have atrial fibrillation is to have an electrocardiogram (EKG or ECG). An EKG is a test that checks for problems with the heart's electrical activity.

You might also have lab tests and an echocardiogram. An echocardiogram can show how well your heart is pumping and whether your heart valves are damaged.

How is it treated?

Your treatment will depend on the cause of your atrial fibrillation, your symptoms, and your risk for stroke.

Medicines are an important part of treatment. They may include:

• Blood-thinning medicine to help prevent strokes.
• Rate-control medicines to keep your heart from beating too fast during atrial fibrillation.
• Rhythm-control medicines to help bring your heart rhythm back to normal.

Doctors sometimes use a procedure called cardioversion to try to get the heartbeat back to normal. This can be done using either medicine or a low-voltage electrical shock (electrical cardioversion).

If you have symptoms that are hard to live with, ablation may help. It destroys small areas of the heart to create scar tissue. The scar tissue blocks or destroys the areas that are causing the abnormal heart rhythm.

What can you do at home for atrial fibrillation?

Atrial fibrillation is often the result of heart disease or damage. So making changes that improve the condition of your heart may also improve your overall health.

• Don't smoke. Avoid second-hand smoke too.
• Eat a heart-healthy diet with plenty of fish, fruits, vegetables, beans, high-fibre grains and breads, and olive oil.
• Get regular exercise on most, preferably all, days of the week. Your doctor can suggest a safe level of exercise for you.
• Stay at a healthy weight. Lose weight if you need to.
• Manage other health problems such as high blood pressure, high cholesterol, and diabetes.
• Manage your stress. Stress can damage your heart.
• Avoid alcohol if it triggers symptoms.
• Avoid getting sick from the flu. Get a flu shot every year.

Cause

Atrial fibrillation is a problem with the heart's electrical system.

When something goes wrong with this system, it's usually because of other health problems that are causing wear and tear on the heart or making it hard for the heart to do its job. Sometimes it's because of lifestyle habits—such as smoking or heavy drinking—that are hard on the heart.

Problems that affect the heart's structure

Atrial fibrillation is often caused by a health problem that directly affects the heart, including:

• High blood pressure.
• Coronary artery disease.
• Heart attack.
• Heart failure.
• Heart valve disease.
• Cardiomyopathy.

Other health problems

Atrial fibrillation can also be caused by other health problems, including:

• Hyperthyroidism.
• Lung disease, such as COPD.
• Having heart surgery or other open-chest surgery.
• Taking certain prescription medicines, such as salbutamol or theophylline.

Atrial fibrillation caused by a condition that is treatable, such as pneumonia or hyperthyroidism, often goes away when that condition is treated.

In some cases, doctors cannot find the cause of atrial fibrillation. These cases are called lone atrial fibrillation. Lone atrial fibrillation occurs more often in people younger than 65. It often stops on its own. But it may need to be treated.

Symptoms

Atrial fibrillation is often discovered during routine medical checkups, because many people don't have symptoms. Others may notice an irregular pulse but don't have other symptoms.

Mild symptoms of atrial fibrillation may occur immediately. More serious problems may occur after the start of atrial fibrillation and over the course of several days. So it is important to identify symptoms and get treatment as soon as possible.

Symptoms include:

• Heart palpitations.
• Irregular pulse.
• Shortness of breath, especially during physical activity or emotional stress.
• Weakness, fatigue.
• Chest pain.
• Dizziness, confusion.
• Light-headedness or fainting (syncope).
• Sweating.
• Feeling anxious.

Checking your pulse

Checking your pulse is important, because many people don't have symptoms of atrial fibrillation. Ask your doctor how often you should check your heartbeat. If you have atrial fibrillation but have trouble feeling if your heart beat is irregular, you can buy a low-priced stethoscope to listen to your heart.

If you notice that your heartbeat doesn't have a regular rhythm, talk to your doctor.

Paroxysmal atrial fibrillation

Atrial fibrillation is called paroxysmal if episodes last 7 days or less. The episodes may go away on their own or they go away after treatment.

Typically, over time, episodes of paroxysmal atrial fibrillation come on more often and last longer.

Persistent atrial fibrillation

Over time, episodes of atrial fibrillation typically last longer and often don't go away on their own. If an episode lasts more than 7 days, this is called persistent atrial fibrillation. 

Permanent atrial fibrillation

Atrial fibrillation is called permanent if you and your doctor have decided not to restore a normal heart rhythm after a year of continuous atrial fibrillation. Although it is called permanent, you can change your mind later and try treatments to restore a normal heart rhythm.

What Increases Your Risk

A risk factor is anything that increases your chances of getting sick or having a problem. Risk factors for atrial fibrillation include:

• Age older than 65.
• Being male.
• Obesity.
• Sleep apnea.
• A family history of atrial fibrillation.
• Certain other health problems can cause atrial fibrillation. For a list of these problems, see Cause.

Lifestyle choices

You may have certain habits that increase your risk for atrial fibrillation because they can cause wear and tear on your heart. These lifestyle choices include:

• Long-term, heavy alcohol use, or drinking a large amount of alcohol at one time (binge drinking).
• Smoking.

When to Call a Doctor

Call
911
or other emergency services immediately if you:

• Have symptoms of a heart attack, such as chest pain or pressure, shortness of breath, and nausea.
• Have symptoms of a stroke, such as sudden vision changes; trouble speaking; or numbness, tingling, weakness, or loss of movement in your face or an arm or a leg.
• Feel faint and have an irregular heartbeat.

If you see someone pass out, call 911 or other emergency services immediately.

Call your doctor if you have:

• An irregular heart rate.
• Heart palpitations.
• Periods of unexplained light-headedness, dizziness, or confusion.
• An episode of fainting or you come close to fainting for no apparent reason.
• Shortness of breath that gets worse with exercise.

If you take a blood thinner

If you take blood-thinning medicine, watch for signs of bleeding.

Call
911
or other emergency services immediately if:

• You have a sudden, severe headache that is different from past headaches. (It may be a sign of bleeding in the brain.)

Call your doctor right away if you have any unusual bleeding, such as:

• Nosebleeds.
• Vaginal bleeding that is different (heavier, more frequent, at a different time of the month) than what you are used to.
• Bloody or black stools, or rectal bleeding.
• Bloody or pink urine.

Who to see

Your family doctor or general practitioner can detect, diagnose and, in some cases, treat atrial fibrillation.

The following specialists can treat people who have severe symptoms:

• Cardiologist
• Cardiac electrophysiologist
• Internist who specializes in cardiology

Examinations and Tests

An electrocardiogram (EKG, ECG) is the best and simplest way to find out whether you have atrial fibrillation. It is usually done along with a medical history and physical examination.

If your doctor suspects that you have atrial fibrillation that comes and goes, he or she may ask you to use a device to record your heart rhythm for a while. This is referred to by several names, including ambulatory electrocardiogram, ambulatory EKG, Holter monitoring, 24-hour EKG, and cardiac event monitoring. Your doctor might also use this device to check how well a medicine is working to control your heart rate.

Other tests

Other tests your doctor may recommend include:

• Electrophysiology (EP) study
  . This test can help your doctor see if there is a problem with your heartbeat (heart rhythm) and find out how to fix it.
• Exercise electrocardiogram
  . Also called a stress test, this test will help your doctor see whether you have coronary artery disease.
• Echocardiogram
  . This test can show whether your heart valves are damaged, how well your heart is pumping, and whether you have heart failure or have had a heart attack.
• A blood test to check for hyperthyroidism.
• Prothrombin time and INR
  . If you take warfarin (such as Coumadin), you will need to have this type of blood test regularly to check how long it takes for your blood to clot.

Treatment Overview

It's hard to say exactly what your treatment for atrial fibrillation will be, because it depends so much on your symptoms and your risk for other health problems.

Treatments are aimed at helping you feel better and preventing future problems, especially stroke and heart failure. There are three main types of treatment:

• Treatment to slow your heart rate.
• Treatment to control your heart rhythm.
• Treatment to prevent stroke.

Treatment to slow your heart rate

Rate-control medicines are used if your heart rate is too fast.

They usually do not return your heart to a normal rhythm—in other words, your heartbeat will still be irregular. But these medicines can keep your heart from beating at a dangerously fast rate. These medicines may also relieve symptoms.

Treatment to control your heart rhythm

Treatment to control your heart rhythm is done to try to stop atrial fibrillation and keep it from returning. It may also help your symptoms. Treatments include:

• Rhythm-control medicines, also called antiarrhythmics.
• Electrical cardioversion. This procedure uses a low-voltage electrical shock to return the heart to a normal rhythm.
  • Atrial Fibrillation: Should I Try Electrical Cardioversion?
• Catheter ablation. This minimally invasive procedure destroys tiny areas in the heart that cause atrial fibrillation. It can relieve symptoms and improve quality of life.
  • Atrial Fibrillation: Should I Have Catheter Ablation?
• AV node ablation is another type of catheter ablation. It does not stop atrial fibrillation but it can relieve symptoms.
• Maze procedure. This may be done as a minimally invasive surgery or during open-heart surgery. It creates scar tissue that blocks excess electrical impulses from travelling through your heart.

Treatment to prevent stroke

Atrial fibrillation is dangerous because if the heartbeat isn't strong and steady, blood can collect, or pool, in the atria. And pooled blood is more likely to form clots. Clots can travel through the bloodstream to the brain and cause a stroke.

Your doctor can help you know your risk of a stroke based on your age and health. This information can help you and your doctor decide how to lower your risk.

If you are at an average-to-high risk of having a stroke, your doctor may prescribe long-term use of an anticoagulant medicine to lower this risk.

If you are at low risk of having a stroke, you may choose to take daily aspirin or to not take a blood thinning medicine.

For more information, see Medications.

A device (such as Watchman) may be implanted to try to lower the risk of stroke. The device may prevent blood clots from moving out of the heart and causing a stroke. The device is placed inside of the heart with a procedure that uses catheters in blood vessels. This device might be used in some people who cannot take an anticoagulant long-term.

For more information on this device, see Other Treatments.

Prevention

Do all you can to prevent heart disease, which is a cause of atrial fibrillation. Take steps toward a heart-healthy lifestyle.

• Manage your stress.
• Exercise regularly.
• Eat heart-healthy foods.
• Control your blood pressure.
• Lose extra weight.
• Don't smoke.

Living With Atrial Fibrillation

Many people are able to live full and active lives with atrial fibrillation. Most people don't have to change their daily activities.

Because atrial fibrillation is often the result of a heart condition, making changes to improve your heart condition will usually improve your overall health.

Have a heart-healthy lifestyle

A heart-healthy lifestyle may help reduce how often you have episodes of atrial fibrillation. If you are overweight, losing weight can help relieve symptoms.

• Don't smoke. If you need help quitting, see the topic Quitting Smoking.
• Eat heart-healthy foods.
• Try an exercise program. Talk to your doctor about what type and level of exercise is safe for you.
• Stay at a healthy weight. Lose weight if you need to. For more information, see the topic Weight Management.
• Avoid alcohol if it triggers symptoms.
• Control your stress. Treatments like yoga, biofeedback, and meditation may help.

Prevent other health problems

• If needed, take medicines that help lower your risk of heart disease. These include cholesterol and blood pressure medicine.
• Talk with your doctor or pharmacist before taking any new medicine. Tell your doctor all of the medicines you take. Some prescription and non-prescription medicine can interact with your heart medicines. Some non-prescription medicines, especially cold and herbal remedies, contain stimulants that can trigger atrial fibrillation.
• Get an influenza (flu) vaccine every year.
• Know the signs of sleep apnea. Tell your doctor if you have symptoms such as snoring and feeling sleepy during the day. Many people with atrial fibrillation also have this condition.

Take medicines safely

When you take a blood-thinning medicine, you need to take extra steps to avoid bleeding problems, such as preventing falls and injuries. If you take warfarin, you also get regular blood tests and watch how much vitamin K you eat or drink.

Medications

If you have atrial fibrillation, you may take a medicine to help prevent a stroke. You may also take a medicine that slows your heart rate or controls your heart rhythm.

Medicine to prevent a stroke

Your doctor can help you know your risk of a stroke based on your age and health. This information can help you and your doctor decide how to lower your risk.

Anticoagulant medicines, also called blood thinners, are recommended for most people with atrial fibrillation who are at average to high risk of stroke.

If you are at low risk of having a stroke, you may choose to not take an anticoagulant. Or you may choose to take aspirin, a common over-the-counter pain reliever that also has anti-platelet properties. This can help prevent blood clots from forming.

Anticoagulant choices include:

• Apixaban (Eliquis).
• Dabigatran (Pradaxa).
• Edoxaban (Lixiana).
• Rivaroxaban (Xarelto).
• Warfarin (Coumadin).

Medicine to slow your heart rate

Rate-control medicines are used if your heart rate is too fast. The medicine slows your heart rate. Your heart rate may not need to be very low. A heart rate of 110 beats per minute may be enough to help you.

These medicines include:

• Beta-blockers.
• Calcium channel blockers.
• Digoxin.

Rate-control medicines may relieve symptoms caused by the fast heart rate. But these medicines may not relieve other symptoms caused by atrial fibrillation.

Medicine to control your heart rhythm

Rhythm-control medicines (also known as antiarrhythmics) help return the heart to its normal rhythm and keep atrial fibrillation from returning. They may help relieve symptoms caused by an irregular heart rate.

Other Treatment

Electrical cardioversion

Electrical cardioversion uses a low-voltage electrical shock to return an irregular heartbeat to a normal rhythm.

• Atrial Fibrillation: Should I Try Electrical Cardioversion?

Catheter ablation

Catheter ablation is a minimally invasive procedure. It destroys the heart tissue that causes atrial fibrillation and that keeps atrial fibrillation going after it starts.

For help deciding whether catheter ablation is a good choice for you, see:

• Atrial Fibrillation: Should I Have Catheter Ablation?

AV node ablation is another type of catheter ablation. It does not stop atrial fibrillation but it can relieve symptoms.

Device to prevent stroke

An implanted device (such as Watchman) is a newer way to try to lower the risk of stroke caused by atrial fibrillation. Doctors call the device a left atrial appendage closure device. This means that the device closes a very small part of the left atrium (a chamber of the heart) where blood clots might form. The device may prevent these blood clots from moving out of the heart and causing a stroke.

The device is placed inside of the heart with a procedure that uses catheters in blood vessels. This procedure is available at a small number of hospitals. The device is not right for everyone. It might be used for a person who cannot take an anticoagulant long-term. Research shows that the device may work as well as the anticoagulant called warfarin to prevent stroke. It is not known how the device compares to other anticoagulants. There is a chance of harm from the procedure and the device, including bleeding and blood clots.^{footnote 1} Doctors do not know the long-term benefits and risks of the device. You and your doctor can decide if the device is right for you.