(say "AY-tree-uhl fih-bruh-LAY-shun") is the most common type of irregular heartbeat (arrhythmia).
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,
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
damage or strain the heart commonly cause atrial fibrillation. These
Other possible causes include:
Sometimes doctors can't find the cause. Doctors call this lone atrial fibrillation.
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.
The doctor will ask questions about your past health, do a physical exam, 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.
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:
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 symptoms keep bothering you, 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.
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
Health Tools help you make wise health decisions or take action to improve your health.
Learning about atrial fibrillation:
Living with atrial fibrillation:
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.
Atrial fibrillation is often caused by a health problem that directly affects the heart, including:
Atrial fibrillation can also be caused by other health problems, including:
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.
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.
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. Once a month might be right for you.
If you notice that your heartbeat doesn't have a regular
rhythm, talk to your doctor.
When atrial fibrillation comes on suddenly, lasts a short time, and goes away on its own, it is called paroxysmal atrial fibrillation. Typically, over time, episodes of paroxysmal atrial fibrillation come on more often and last longer.
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. Treatment with medicine or cardioversion can restore a normal rhythm. This normal rhythm may last for several weeks or longer before atrial fibrillation happens again.
Atrial fibrillation might start to happen all of the time. If atrial fibrillation has happened all of the time for at least 1 year, this is called permanent atrial fibrillation. Your treatments have not restored a normal rhythm, or you and your doctor have decided to stop trying to restore a normal rhythm.
A risk factor is anything that increases your chances of getting sick or having a problem. Risk factors for
atrial fibrillation include:
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:
Call 911 or other emergency services immediately if you:
If you see someone pass out, call 911 or other emergency services immediately.
Call your doctor if you
If you take blood-thinning medicine, such as an anticoagulant or aspirin, watch for signs of bleeding.
Call 911 if:
Call your doctor right away if:
If you are injured, apply pressure to stop the bleeding. Realize that it
will take longer than you are used to for the bleeding to stop. If you can't get the bleeding to stop, call your doctor.
The following health professionals can
detect, diagnose and, in some cases, treat atrial fibrillation:
The following specialists can treat people who have severe symptoms:
electrocardiogram (EKG, ECG) is the best and simplest
way to find out whether you have
atrial fibrillation. It is usually done along
medical history and physical exam.
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 your doctor may recommend include:
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:
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 is done to try to stop atrial fibrillation and keep it from returning. It may also help your symptoms. Treatments include:
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 other areas such as the legs. If clots travel to the brain, they can block blood flow and cause a stroke.
If you are at an average-to-high risk of having a stroke, your doctor may prescribe long-term use of an anticoagulant medicine, such as warfarin, to lower this risk.
If you are at low risk of having a stroke or you cannot take an anticoagulant, you may choose to take daily aspirin.
For more information, see Medications.
Do all you can to prevent heart disease, which is a cause of atrial fibrillation. Take steps toward a heart-healthy lifestyle.
Many people are able to live full and
active lives with atrial fibrillation. Most people don't have to change their daily activities.
atrial fibrillation is often the result of a heart
condition, making changes to improve your heart condition will usually improve
your overall health.
For more information, see:
When you take an anticoagulant (also called a blood thinner), 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.
If you have atrial fibrillation, you will likely take a medicine to help prevent a
stroke. You may also take a medicine that controls
your heart rate or your heart rhythm.
Anticoagulant medicines, also called blood thinners, are recommended for
most people with atrial fibrillation who are at average to high risk of
Anticoagulant choices include:
If you are age 55 or older and have atrial fibrillation,
you can find your risk of having a stroke in the next 5 years using this
Interactive Tool: What Is Your Risk for a Stroke if You Have Atrial Fibrillation?
For help deciding about an anticoagulant, see:
If you are at low
risk of stroke or cannot take anticoagulants, your doctor may recommend that
aspirin. It doesn't work as well as anticoagulant
medicines in preventing clots, but it doesn't have as many side effects.
Your doctor may have you take other
antiplatelet medicines, such as clopidogrel (Plavix),
along with aspirin or instead of aspirin. When aspirin and
clopidogrel are used together, they may reduce the risk for stroke more than
aspirin alone. This combination of clopidogrel and aspirin doesn't work as well as an anticoagulant to prevent clots. Also, this combination is more likely to cause bleeding than
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.1
Rate-control medicines may relieve symptoms caused by the fast heart rate. But these medicines may not relieve other symptoms caused by atrial fibrillation.
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.
Electrical cardioversion uses a low-voltage electrical shock to return an irregular heartbeat to a normal rhythm.
If medicine doesn't help atrial fibrillation, a procedure called catheter ablation may be done. 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:
Pacemakers are sometimes needed by people who have atrial fibrillation.
Visit the American Heart Association (AHA) website for information on
physical activity, diet, and various heart-related conditions. You can search for information on heart disease and stroke, share information with friends and family, and use tools to help you make heart-healthy goals and plans. Contact the AHA to find your
nearest local or state AHA group. The AHA provides brochures and information
about support groups and community programs, including Mended Hearts, a
nationwide organization whose members visit people with heart problems and
provide information and support.
CardioSmart is an online education and support program that can be your partner in heart health. This website engages, informs, and empowers people to take part in their own care and to work well with their health care teams. It has tools and resources to help you prevent, treat, and/or manage heart diseases.
You can set health and wellness goals and track your progress with online tools. You can track your weight, waist measurement, blood pressure, and activity. You can use calculators to help you find your body mass index (BMI) and check your risk for heart problems. You can search for a cardiologist. And you can find medicine information and prepare for your next appointment. Also, you can join online communities to connect with peers and take heart-healthy challenges.
CardioSmart was designed by cardiovascular professionals at the American College of Cardiology, a nonprofit medical society. Members include doctors, nurses, and surgeons.
The Heart Rhythm Society provides information for
patients and the public about heart rhythm problems. The website includes a
section that focuses on patient information. This information includes causes,
prevention, tests, treatment, and patient stories about heart rhythm problems.
You can use the Find a Specialist section of the website to search for a heart
rhythm specialist practicing in your area.
The U.S. National Heart, Lung, and Blood Institute
(NHLBI) information center offers information and publications about preventing
CitationsVan Gelder IC, et al. (2010). Lenient versus strict rate control in patients with atrial fibrillation. New England Journal of Medicine, 362(15): 1363–1373.Other Works ConsultedCalkins H, et al. (2012). 2012 HRS/EHRA/ECAS expert consensus statement on catheter and surgical ablation of atrial fibrillation. Heart Rhythm, 9(4): 632–696.e21.Fuster V, et al. (2011). 2011 ACCF/AHA/HRS focused update incorporated into the ACC/AHA/ESC 2006 guidelines for the management of patients with atrial fibrillation: A report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines. Circulation, 123(10): e269–e367.Lane DA, et al. (2011). Atrial fibrillation (chronic), search date June 2011. BMJ Clinical Evidence. Available online: http://www.clinicalevidence.com.Lip GYH, Apostolakis S (2011). Atrial fibrillation (acute onset), search date April 2010. BMJ Clinical Evidence. Available online: http://www.clinicalevidence.com.Miller JM, Zipes DP (2012). Therapy for cardiac arrhythmias. In RO Bonow et al., eds., Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine, 9th ed., vol. 1, pp. 710–744. Philadelphia: Saunders.Prystowsky EN, et al. (2011). Atrial fibrillation, atrial flutter, and atrial tachycardia. In V Fuster et al., eds., Hurst's The Heart, 13th ed., vol. 1, pp. 963–986. New York: McGraw-Hill.Roy D, et al. (2008). Rhythm control versus rate control for atrial fibrillation and heart failure. New England Journal of Medicine, 358(25): 2667–2677.Shea JB, Sears SF (2008). A patient's guide to living with atrial fibrillation. Circulation, 117(20): e340–e343.Sherman DG, et al. (2005). Occurrence and characteristics of stroke events in the atrial fibrillation follow-up investigation of sinus rhythm management (AFFIRM) study. Archives of Internal Medicine, 165(10): 1185–1191.Treatment of atrial fibrillation (2010). Treatment Guidelines From The Medical Letter, 8(97): 65–70.Van Gelder IC, et al. (2010). Lenient versus strict rate control in patients with atrial fibrillation. New England Journal of Medicine, 362(15): 1363–1373.Wang TJ, et al. (2003). A risk score for predicting stroke or death in individuals with new-onset atrial fibrillation in the community: The Framingham heart study. JAMA, 290(8): 1049–1056.You JJ, et al. (2012). Antithrombotic therapy for atrial fibrillation: Antithrombotic therapy and prevention of thrombosis, 9th ed.—American College of Chest Physicians evidence-based clinical practice guidelines. Chest, 141(2, Suppl): e531S–e575S.
December 14, 2012
Rakesh K. Pai, MD, FACC - Cardiology, Electrophysiology & John M. Miller, MD, FACC - Cardiology, Electrophysiology
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