Atrial fibrillation is very common, particularly as patients get older. Around 15% of people over the age of 75 get atrial fibrillation.
Some patients’ hearts go in and out of atrial fibrillation, with the irregular heart rhythm lasting anywhere from a few seconds, to days at a time before returning to normal. Other patients have atrial fibrillation that is chronic; they are in atrial fibrillation 100% of the time
Risk Factors for A-Fib
Other than age, the most common risk factors are:
- High blood pressure
- Overactive thyroid
- Heart valve problems such as mitral regurgitation or rheumatic heart disease
- Coronary artery disease
In addition, certain lifestyle features can be risk factors for atrial fibrillation, including:
- Sedentary lifestyle
- Obstructive sleep apnea
- Alcohol use
Symptoms of Atrial Fibrillation
Although some patients may be completely asymptomatic with atrial fibrillation, most have typical and predictable symptoms, including:
- Palpitations, or an awareness of their heart beating irregularly, either in their chest, or in the neck
- Shortness of breath with routine activity
- Chest pain or pressure
- Lightheadedness or dizziness
- Fatigue, and declining stamina
The most worrisome symptom or complication of atrial fibrillation is that it significantly increases the risk of stroke. When the heart is in atrial fibrillation, the upper chambers of the heart do not squeeze in a coordinated fashion but instead quiver, or “fibrillate.” Because these chambers do not squeeze normally, blood can pool, and blood clots can form. These clots can break loose and travel to the brain, causing a stroke.
Patients with atrial fibrillation who also have other risk factors for stroke— including being female; age over 65; high blood pressure; history of heart failure, diabetes, prior stroke; or known blockages in heart arteries or other arteries in the body—usually benefit from taking blood thinners to decrease risk of stroke. In fact, blood thinners—and this does not include aspirin—are a critical part of the treatment for patients who have atrial fibrillation to help reduce the risk of stroke.
How to Test for A-Fib
Several tests may be used to diagnose atrial fibrillation:
- Physical exam: Often times, an irregular heart beat found by checking the pulse or listening to the heart with a stethoscope can suggest the presence of atrial fibrillation. There are multiple reasons for irregular heartbeats, many of which are not dangerous, so if an abnormal heart rhythm is detected on exam, it needs additional evaluation with an electrocardiogram.
- Electrocardiogram (ECG): An electrical tracing of the heart, which will have a characteristic pattern if atrial fibrillation is present.
- Heart Rhythm Monitors: Some patients have atrial fibrillation only some of the time, and so it can be more difficult to detect. Their hearts may be in normal rhythm when in the doctor’s office but then have atrial fibrillation when they are at home. These patients can be diagnosed with a monitor that they can wear at home up to 30 days at a time. There are different types of monitors, some of which are an adhesive patch which sticks to the chest; other types are about the size of a cell phone and can be attached to the belt or worn around the neck.
- Echocardiography, or cardiac ultrasound: A common test to ensure that there are no heart valve problems that are contributing to the irregular heartbeat.
What Are the Treatments for A-Fib?
Many patients require blood thinners to reduce the risk of stroke associated with atrial fibrillation. Even patients who cannot feel the atrial fibrillation or who are in atrial fibrillation only a small percentage of the time often benefit from blood thinners.
Depending on symptoms, heart rate, and patient preference, there are two main strategies to treat atrial fibrillation:
- A rate control strategy may be used in older patients who do not have significant symptoms with atrial fibrillation. This strategy uses medication to keep the heart from racing in atrial fibrillation, but does not try to restore normal rhythm. These patients also receive blood thinners.
- A rhythm control strategy is frequently used in younger patients and in patients who have symptoms associated with atrial fibrillation. The primary goal here is to restore normal rhythm either with medication, cardioversion, or an ablation procedure.
- Medications: There are many different types of medications which can be used alone or in combination to treat atrial fibrillation. Some of these medications are designed to keep the heart from racing, others are designed specifically to keep the heart in normal rhythm. Some of the medications have the potential to cause other heart rhythm problems and so need to be started while patients are in the hospital and under supervision.
- Cardioversion: A procedure done in the hospital in which patients are sedated and then receive an electrical shock to the chest to break the short circuit of the atrial fibrillation and allow normal heart rhythm to be restored. All patients who receive cardioversion must be on blood thinners. Oftentimes, immediately prior to the cardioversion, patients undergo a transesophageal echocardiogram, an ultrasound procedure (also under sedation). After receiving sedation to make them comfortable, patients swallow an ultrasound probe to allow close-up pictures to be taken of the heart from the patient’s esophagus. This is done to make sure no blood clots have formed in the heart because of the atrial fibrillation.
- Ablation: Catheter ablation is an invasive treatment for atrial fibrillation that is reserved for patients who remain symptomatic with atrial fibrillation despite medications and cardioversion therapy. During this procedure, special wires are advanced into the heart, and the abnormal heart tissue that is triggering the atrial fibrillation is identified and burned, so it can no longer trigger the fibrillation.
Watchman™ Left Atrial Appendage Closure: Patients who have atrial fibrillation are often at increased risk for stroke and benefit from being on blood thinners. Not all patients can tolerate blood thinners, however. In these patients, stroke risk can be reduced by placing a Watchman device in the heart.