Michael W. Rich, MD, FACC, AGSF
Professor of Medicine
Washington University School of Medicine
St. Louis, Missouri
Q: What is atrial fibrillation?
A: Atrial fibrillation is a rapid and irregular beating of the atria, which are the upper chambers of the heart. It is one of the more common types of heart rhythm problems.
Q: What causes atrial fibrillation?
A: Atrial fibrillation usually occurs because there has been damage or scarring of the atria. The risk of atrial fibrillation also increases with age. It is somewhat more common in men than in women.
Common causes of atrial fibrillation include heart conditions such as high blood pressure, previous heart attack, heart valve disease, and heart failure. Lung diseases such as emphysema and sleep apnea can also cause atrial fibrillation. In addition, atrial fibrillation may occur following major surgery. Sometimes the cause isn’t clear.
Q: Why is it important to get checked for atrial fibrillation? What can happen if you have atrial fibrillation but don’t get treatment?
A: It is important to get diagnosed and treated, because atrial fibrillation can cause serious symptoms and complications. It can lead to heart failure and to stroke. In fact, atrial fibrillation is a leading cause of stroke in older adults.
Q: How does atrial fibrillation cause a stroke?
The rapid and irregular beating of the heart that occurs with atrial fibrillation can allow a blood clot to form in the atria. If a blood clot breaks off and goes to the brain, it will cause a stroke. The type of stroke and symptoms will depend on where the clot goes in the brain. To decrease the risk of stroke, medicines that prevent blood clots from forming in the heart are often used in the treatment of atrial fibrillation.
Warning Signs of Stroke
Stroke warning signs vary. Common signs include:
- sudden numbness or weakness on one side of your face, arm, or leg
- slurred speech, garbled speech, or difficulty finding words
- sudden difficulty with balance or coordination
- sudden loss of vision, blurred vision, or double vision
Less common signs of stroke include:
- severe headache or sudden dizziness
- sudden confusion or change in level of awareness
If you have these symptoms call 911 immediately.
Q: How common is atrial fibrillation in older adults?
A: The risk of atrial fibrillation increases with age. About 10 percent of people 80 years or older are diagnosed with atrial fibrillation, compared to less than 2 percent in people ages 50 to 59 years.
Q: Are there other things that also increase the risk of atrial fibrillation?
A: Yes. People with high blood pressure that is not well-treated have an increased risk of atrial fibrillation. People who have one of the below also have a higher risk:
- had one or more previous heart attacks
- an abnormal heart valve
- other heart problems or have had heart surgery
- emphysema or other lung diseases
An overactive thyroid gland and sleep apnea (a disorder that interrupts your breathing while you sleep) can also increase risk. There is also a tendency for atrial fibrillation to run in families.
Q: What are the symptoms of atrial fibrillation?
Symptoms of atrial fibrillation can vary from one person to another. Some people don’t have any obvious symptoms. They don’t realize they have atrial fibrillation unless their healthcare provider diagnoses it. Others have symptoms only sometimes.
Common symptoms are:
- a feeling of “quivering,” “racing”, "fluttering", or “flip-flopping”
- palpitations (fast, strong, or irregular heartbeats)
- shortness of breath
- difficulty exercising without being exhausted.
Additional common symptoms include:
- chest discomfort
There are many conditions other than atrial fibrillation that can cause similar symptoms, so if you have these symptoms, talk to your healthcare provider.
Q: How is atrial fibrillation diagnosed?
If atrial fibrillation is ongoing, the heartbeat and pulse will be irregular. An electrocardiogram (EKG) will confirm the diagnosis. If atrial fibrillation is intermittent, your healthcare provider may have you wear a heart monitor at home for a period of time to try to detect it.
Q: Are any other tests needed?
When a diagnosis of atrial fibrillation is first made, the healthcare provider will usually order several tests to try to determine the cause. The most common tests are an echocardiogram (sound wave picture of the heart) and blood tests to check for abnormalities in blood chemistry (for example, low potassium) or thyroid function. In some cases, additional tests may be ordered.
Q: If I have atrial fibrillation, what kind of treatment will help?
A: Your treatment will depend on what is causing your atrial fibrillation. For example, whether it is caused by heart disease, high blood pressure, or an overactive thyroid gland.
The main goals of treatment are to relieve symptoms and to reduce the risk for stroke. Some medications , including beta-blockers, are used to control the heart rate. In some cases, the healthcare provider may recommend that an electric shock be given to the heart under anesthesia to restore normal rhythm.
Several medicines are effective in preventing blood clots from forming in the heart and reducing the risk of stroke. These anti-clot drugs are often referred to as "blood thinners", but this term is not accurate because these drugs do not actually thin the blood.
The oldest and most widely used anti-clot medication is warfarin (Coumadin). Warfarin is very effective in reducing the risk of stroke in people with atrial fibrillation, but it is a challenging drug to use because it requires frequent monitoring and adjusting the dosage. It also interacts with many other medications and foods.
Newer drugs include dabigatran (Pradaxa), rivaroxaban (Xarelto), and apixaban (Eliquis). These drugs are at least as effective as warfarin in preventing strokes. They are also less likely to cause dangerous bleeding. They don't require regular blood tests for monitoring and interactions with other drugs and foods are much less common than with warfarin. Disadvantages of the new drugs are that there is currently no antidote in the event the bleeding occurs and they are more expensive than warfarin.
If medication does not control your atrial fibrillation, your healthcare provider may refer you to a heart rhythm specialist to pursue additional treatments.
Q: What else should I know about managing atrial fibrillation?
Here are some tips to help you manage atrial fibrillation:
- If you are taking an anti-clot drug, tell your healthcare provider if you have any unusual bruises or bleeding. This may be a sign that the dose is too high.
- All medications can cause side effects. Tell your healthcare provider if you think that one or more of your medicines is causing a problem.
- Avoid smoking, excess alcohol, and excess caffeine, all of which can trigger atrial fibrillation. Men should limit alcohol intake to no more than 2 drinks per day. Women should limit alcohol to no more than 1 drink per day.
- Exercising regularly, eating a heart-healthy diet, and maintaining a suitable weight are good habits for staying healthy. Talk to your healthcare provider about what you can do to control atrial fibrillation and reduce your risk for other heart problems.
Last Updated July 2014