What is atrial fibrillation?
Atrial fibrillation, a type of irregular heart rhythm (arrhythmia), is a common condition, especially among older people.
Normally, your heart beats in a regular and timed fashion. In atrial fibrillation, abnormal electrical signals cause the upper parts of the heart called the atria to quiver, or fibrillate. A fibrillating heart may not pump out as much blood as a normal heart.
Atrial fibrillation also increases your risk for strokes. The fibrillating heart allows blood to collect, or pool, in the atria. The pooled blood is more likely to form a clot. If the heart pumps the clot into the bloodstream, it can travel to the brain. The clot can block blood flow in the brain, causing a stroke.
For this reason, doctors recommend that most people with atrial fibrillation take warfarin (Coumadin, for example) or aspirin. These drugs can keep blood clots from forming.
Underlying heart diseases commonly cause atrial fibrillation. They include:
High blood pressure. Having high blood pressure that is not controlled by medicine is the most common reason people get atrial fibrillation.
Coronary artery disease (CAD) and a prior heart attack.
Heart valve disease, especially of the mitral valve.
Atrial fibrillation may be caused by other medical conditions, such as an overactive thyroid or lung disease. Binge drinking can cause episodes of atrial fibrillation. Heavy drinking (more than 3 drinks a day) over many years can cause long-lasting atrial fibrillation.
Sometimes doctors cannot find a cause for atrial fibrillation.
Many people with atrial fibrillation do not have any symptoms. Others have symptoms such as weakness, shortness of breath, and a fluttering or thumping feeling in the chest (palpitations). Sometimes people have chest pain or faint with atrial fibrillation.
The U.S. National Stroke Association recommends that everyone, particularly those age 55 or older, check his or her heartbeat once per month. This is important because many people do not know that they have atrial fibrillation. If you notice that your heartbeat does not have a regular rhythm, talk to your doctor. You may be at risk for stroke.
An electrocardiogram (EKG, ECG) is the best and simplest way to tell whether you have atrial fibrillation. An electrocardiogram is a recording of the electrical activity of your heart. It is usually done along with asking questions about your medical history and doing a physical exam, lab tests, and a chest X-ray.
Atrial fibrillation is most commonly seen in people older than 65 who have underlying heart disease. This type of atrial fibrillation can be difficult to treat. At first, spells of atrial fibrillation may come on suddenly and last a short time before going away on their own. This is called paroxysmal atrial fibrillation.
Over time, the spells usually last longer and occur more often. With increasing spells, atrial fibrillation often no longer goes away on its own. Sometimes, doctors perform a procedure called cardioversion, using either medication or low-voltage electrical shock (electrical cardioversion), to return the irregular heartbeat to a normal rhythm (normal sinus rhythm). When cardioversion is not an option or does not work, medications are usually given to control the heart rate.
People who have atrial fibrillation and an otherwise normal heart are 5 to 6 times more likely to have a stroke than people who do not have atrial fibrillation.1 Most people with atrial fibrillation need to take warfarin (such as Coumadin) to prevent strokes. You will need to have regular blood tests to make sure that the medication is working properly while taking it. Most people who are at low risk for a stroke, such as those younger than 65 without heart disease, may take daily aspirin instead of warfarin. Your doctor will determine whether aspirin or warfarin is right for you.
Many people are able to live full and active lives by taking medicine to control their heart rates. Others become short of breath and weak with normal physical activities and need further treatment. Medicines to control the irregular heart rhythm (antiarrhythmics) are often tried.
If you continue to have serious symptoms, you may choose to have a nonsurgical procedure called ablation. Ablation destroys small areas of the heart, which creates scar tissue. The scar tissue blocks the irregular electrical signals that are causing your irregular heart rhythm. Depending on which type of ablation you have, you may need a permanent pacemaker to keep your heart beating regularly.
Aside from the risk of stroke, it is important to treat atrial fibrillation, because a heart rate that is fast and uncontrolled over a long period can damage the heart and lead to a heart attack and heart failure.
1 Source: www.WebMD.com
Revised: 11/03/09. Copyright © 2006 Clinical Research Associates of Tidewater. All rights reserved.