The Most Common Heart Rhythm Disturbance
Atrial fibrillation (AF) is the most common heart rhythm disturbance, with almost 3 million Americans suffering from it today. Although atrial fibrillation “seems” to be one disease, it is likely a common representation of several disorders of heart rhythm: an erratic, irregular, frequently rapid heartbeat. During AF the atria “quiver” and are unable to effectively pump blood. This leads to stagnation of blood within certain areas of the atria and the formation of clots. AF can be a major cause of problems ranging from fatigue and weakness to stroke and heart failure. AF is known to occur more frequently in older patients and in those with heart disease, however it can happen to anyone at any time.
In Atrial Fibrillation, the electrical signals in the heart are generated from all over the atria at a very high speed. There is no coordination. As a result, the atria quiver like a bag of worms. This is known in medical terms as fibrillation. The AV node (the electrical connection between the atria and the ventricle) is overloaded with signals trying to get through to the ventricles. When this happens, the ventricles also contract rapidly, but not as rapidly as the atria. The heart's atria experience disorganized electrical signals and do not beat in coordination with the ventricles.This results in an irregular and fast heart rate between 100 to 175 beats per minute.
AF can be paroxysmal, persistent or permanent
It is not really known how many patients are in each type of AF, but it is likely that about 40% suffer from paroxysmal AF, 10% from persistent and 50% from permanent.
- Paroxysmal (pah-rox-IHZ-mul): Paroxysmal AF is marked by bouts of AF interspersed with normal (sinus) rhythm. Symptoms may last a few minutes to hours and then stop on their own.
- Persistent: Persistent AF with go into AF and remain in the irregular rhythm until an intervention - either a drug or a shock (cardioversion) - restores them to sinus rhythm. Symptoms last for a few days and usually require medical intervention to stop.
- Permanent: In Permanent AF it is not possible to restore sinus rhythm despite attempts with drugs and/or cardioversions. Symptoms are lasting and do not stop even if treated.
Many patients can live a healthy and productive life after treatment for AF. Remember, it is important that you continue to follow-up with your doctor on a regular basis.
Taking care of yourself is the best way to prevent AF from occurring
Steps toward keeping your heart healthy include making important lifestyle decisions:
- Not smoking
- Eating heart-healthy foods
- Reducing your salt intake, which can help lower blood pressure
- Taking your medications as ordered
- Exercising regularly under your doctor's supervision
- Cutting back on caffeine and alcohol, which can over stimulate your heart and trigger an episode of AF
- Taking steps to reduce stress in your life
Signs and Symptoms
While some people with atrial fibrillation do not experience any symptoms, others may have symptoms that include:
- Palpitations (a feeling of the heart beating rapidly)
- Decreased exercise tolerance
- Shortness of breath
- Chest Pain
- Passing out
Who is at Risk?
The older you are, the greater your risk of developing atrial fibrillation. It also occurs more commonly in women than men. Some factors that increase your risk of getting AF are:
- High blood pressure
- Abnormal heart valves
- Congestive heart failure
- Coronary artery disease
- Congenital heart defects
- An overactive thyroid gland
- Heart stimulants such as caffeine, tobacco or alcohol
- Sick sinus syndrome - this happens when the heart's natural pacemaker does not work properly
- Previous heart surgery
- Emphysema or other chronic lung diseases
- Viral infections
Sometimes AF can occur in healthy people without an apparent cause.
Complications of Atrial Fibrillation
Although often causing troublesome symptoms, AF usually does not result in dangerous complications. Sometimes, however, AF can cause devastating problems, such as:
- Stroke. In AF, the ineffective pumping of blood in the atrium may cause pooling of blood in the heart and cause blood clots to form. If these blood clots dislodge and travel to the brain, they can block blood flow, causing a stroke. If they travel to the leg or intestines then other serious problems can arise. The risk of stroke in AF increases with age, high blood pressure, heart failure, a previous stroke and other factors. Blood thinners can lower your risk of stroke or damage to other organs caused by blood clots, but you must take them all the time and they can be difficult to manage.
- Congestive heart failure. The persistently rapid heart rate associated with AF can weaken the heart muscle, leading to heart failure - a condition in which the heart cannot pump enough blood to meet the body's needs.
Diagnosing Atrial Fibrillation
To make a diagnosis of AF, your doctor may perform one or more of these tests:
- Electrocardiogram (EKG) where electrodes are placed on your chest and body to record the heart's electrical impulses over a few seconds or minutes.
- Holter monitor testing where you wear a portable monitor for 24 hours that records the heart's electrical impulses over the course of the day.
- Echocardiogram, where sound waves are used to provide motion pictures of your heart.