Definition
Atrial fibrillation (A-Fib of AF) is a quivering or irregular heartbeat that can lead to blood clots, stroke, heart failure and other heart-related complications. Regular hearts contract and relax to a regular beat. However, for those with atrial fibrillation, the upper chambers of the heart (the atria) beat irregularly (quiver) instead of beating effectively to move blood into the ventricles.
If a clot breaks off, enters the bloodstream and lodges in an artery leading to the brain, a stroke results. According to the American Heart Association, about 15–20 percent of people who have strokes have this heart arrhythmia. This clot risk is why patients with this condition are put on blood thinners.
Despite the increased risk of heart-related deaths, many A-Fib patients are unaware of the seriousness of this condition.
Blacks have a lower risk of developing A-Fib than whites. However, Blacks that are diagnosed with A-Fib have a higher risk of stroke than whites with the condition.
Causes
Although there is not one set cause for atrial fibrillation, it is often associated with the following conditions:
- After heart surgery
- Cardiomyopathy
- Chronic lung disease
- Congenital heart disease
- Coronary artery disease
- Heart failure
- Heart valve disease
- Hypertension (high blood pressure)
- Pulmonary hypertension
Less common causes:
- Hyperthyroidism
- Pericarditis
- Viral infection
In a small 10% of cases, atrial fibrillation is not tied to any underlying heart disease. In these cases, A-Fib may be related to alcohol or excessive caffeine use, stress, certain drugs, electrolyte or metabolic imbalances, severe infections, or genetic factors. In some cases, no cause can be found. Those over the age of 60 also have an increased risk of A-Fib.
Symptoms
Some people can have atrial fibrillation without symptoms. If you do have symptoms, you may experience the following:
- Heart palpitations – Sudden pounding, fluttering or racing sensation in the chest
- Lack of energy or feeling over-tired
- Dizziness – Feeling light-headed or faint
- Chest discomfort – Pain, pressure or discomfort in the chest
- Shortness of breath – Having difficulty breathing during normal activities and even at rest
Diagnosis
Doctors will use monitoring devices to determine if an irregular heart rhythm (arrhythmia) is causing your symptoms. The most commonly used tests to diagnose atrial fibrillation include:
- Electrocardiogram (ECG or EKG): The ECG draws a picture on graph paper of the electrical impulses traveling through the heart muscle. An EKG provides an electrical “snapshot” of the heart. For people who have symptoms that come and go, a special monitor may need to be used to “capture” the arrhythmia.
- Holter monitor: A small external recorder is worn over a short period of time, usually one to three days. Electrodes (sticky patches) are placed on the skin of your chest. Wires are attached from the electrodes to the monitor. The electrical impulses are continuously recorded and stored in the monitor. After the monitor is removed, a technician uses a computer to analyze the data to evaluate the heart’s rhythm.
- Portable event monitor: A monitor that is worn for about a month for patients who have less frequent irregular heartbeat episodes and symptoms. Electrodes (sticky patches) are placed on the skin of your chest. Wires are attached from the electrodes to the monitor. The patient presses a button to activate the monitor when symptoms occur. The device records the electrical activity of the heart for several seconds. The patient then transmits the device’s recorded information over a telephone line to the doctor’s office for evaluation. The portable event monitor is very useful in determining what heart rhythm is causing your symptoms.
- Transtelephonic monitor: When you develop symptoms of atrial fibrillation, a strip of your current heart rhythm can be transmitted to your doctor’s office over the telephone, using a monitor with two bracelets or by placing the monitor against your chest wall.
Treatments
The main goal of atrial fibrillation treatment will be to help you regain a normal heart rhythm (sinus rhythm), control your heart rate, prevent blood clots and reduce your risk of stroke. Your doctor will recommend a treatment option based on your heart rhythm and symptoms.
Treatment options include:
Medications
Rhythm control medications (antiarrhythmic drugs) help return the heart to its normal sinus rhythm or maintain normal sinus rhythm. Rate control medications are used to help slow the heart rate during atrial fibrillation. Although they don’t control the heart rhythm, they do prevent the ventricles from beating too rapidly. Anticoagulant medications reduce the risk of blood clots and stroke, but they do not eliminate the risk. You should always talk with your doctor about which medications are best for you.
Lifestyle changes
These lifestyle changes can increase your heart health:
- If your irregular heart rhythm occurs more often with certain activities, avoid those activities and tell your doctor. Sometimes, your medications may need to be adjusted.
- Quit smoking.
- Limit your intake of alcohol. Moderation is the key. Ask your doctor for specific alcohol guidelines.
- Limit the use of caffeine. Some people are sensitive to caffeine and may notice more symptoms when using caffeinated products (such as tea, coffee, energy drinks, colas and some over-the-counter medications).
- Beware of stimulants used in cough and cold medications, as some of these medications contain ingredients that may increase the risk of irregular heart rhythms. Read medication labels and ask your doctor or pharmacist what type of cold medication is best for you.
- Control high blood pressure.
- If you are obese or overweight, achieve a desirable weight.
- Control blood sugar levels.
- Treat sleep apnea.
Procedure
When medications do not work to correct or control atrial fibrillation, or when medications are not tolerated, your doctor may recommend one of the following procedures to treat the abnormal heart rhythm:
- electrical cardioversion
- pulmonary vein antrum isolation procedure
- ablation of the AV node followed by pacemaker placement
- surgical ablation (Maze procedure or minimally invasive surgical treatment)