Atrial Fibrillation (AFib10): Must-Know Facts
Symptoms, causes, treatments and who’s at risk
Symptoms, causes, treatments and who’s at risk
Atrial fibrillation (AFib) is the most common type of irregular heartbeat disorder. It affects millions of people in the United States. AFib can lead to serious problems, like stroke and heart failure.
“AFib is a serious heart condition that increases the risk of stroke. It can occur with or without symptoms,” says Nicholas Olson, MD, a cardiac electrophysiologist at Scripps Clinic Anderson Medical Pavilion in La Jolla. “The good news is that AFib is a manageable condition with the help of a good medical team.”
If you have AFib, your doctor may refer you to an electrophysiologist who specializes in the heart's electrical signaling.
Here are 10 important facts to help you understand this condition, including symptoms, causes, treatments, risk factors and treatments:
1. How AFib increases your risk of strokes
AFib affects how well your heart pumps blood. Instead of beating normally, the upper chambers (atria) quiver. This irregular rhythm makes it harder for the heart to move blood efficiently.
As a result, blood can pool in a small pouch of the heart called the left atrial appendage. When blood sits still, clots can form. If a clot breaks loose and travels to the brain, it can block blood flow and cause a stroke.
AFib causes one in seven strokes in the United States, according to the Centers for Disease Control and Prevention (CDC).
It causes or contributes to more than 450,000 hospitalizations and 158,000 deaths each year in the U.S. AFib-related deaths have been rising for more than two decades, according to the CDC.
As the population ages, AFib is expected to affect 12 million Americans by 2030.
2. Common causes of AFib
AFib is the result of abnormal or damaged heart muscle that can lead to rapid electrical firing and an irregular heartbeat.
Common causes include:
- High blood pressure
- Heart attack
- Coronary artery disease
- Abnormal heart valves
- Heart defects
- An overactive thyroid gland
- Exposure to stimulants, such as medications, caffeine, tobacco or alcohol
- Sick sinus syndrome — improper functioning of the heart's natural pacemaker
- Lung diseases
- Previous heart surgery
- Viral infections
- Sleep apnea
- High level athletic activities, such marathon running, long distance biking or swimming
Sometimes no clear cause is found.
3. Is a racing heart always AFib?
Not always. A racing heartbeat could also signal other heart rhythm disorders, such as:
- Atrial flutter
- Supraventricular tachycardia (SVT)
- Ventricular tachycardia (VT)
Only a medical exam, usually including an EKG, can determine the cause.
4. Can AFib lead to heart failure?
AFib can cause heart failure by reducing the heart’s ability to pump blood efficiently to meet the body’s requirements. Heart failure is a serious condition.
“If the heart beats too fast for too long, that can cause the lower pumping chambers to fail and that can cause fluid to retain in the lungs and swelling in the legs. These are symptoms that we would typically associate with heart failure,” Dr. Olson says. “Atrial fibrillation can worsen heart failure as well.”
5. How AFib is diagnosed
AFib is usually diagnosed with an electrocardiogram (ECG or EKG). This test involves placing electrodes on the chest to monitor the heart’s electrical activity. The purpose is to identify any abnormalities in the heart’s rhythm.
An EKG can be done at the doctor’s office. Sometimes patients may wear a portable heart monitor at home for continuous monitoring over a few days or weeks.
Smartwatches and wearable devices with heart rhythm monitoring features are increasingly helping people detect signs of AFib earlier.
6. Are women at higher risk for stroke with AFib?
Yes. Some studies show women are at higher risk of stroke when compared to men with AFib. “This increase in risk appears to be mild but significant when other risk factors for stroke are present in a female patient,” Dr. Olson says.
7. How are risk factors assessed?
Doctors use a medical tool called the CHA2DS2-VASc score to assess the risk of stroke in patients with AFib and help guide treatment to prevent stroke.
The acronym stands for the individual risk factors it assesses:
- Congestive heart failure
- Hypertension
- Age
- Diabetes
- Sex
- Stroke or transient ischemic attack
- Vascular disease
Each risk factor is assigned a score, and the total score indicates the level of stroke risk. Higher scores indicate a higher risk of stroke, prompting the need for more aggressive prevention strategies.
“When a person has a score of 2 or greater, stroke prevention strategies need to be carefully considered,” Dr. Olson explains.
8. Best treatment options for AFib
Treatment depends on symptom severity, stroke risk factors and underlying conditions.
Treatment goals generally include symptom management and stroke prevention. “Issues, such as sleep apnea and blood pressure control, need to be addressed,” Dr. Olson says.
Common treatments include:
- Medications to control heart rate and rhythm
- Blood thinners to prevent clots
- Treating related conditions like sleep apnea
- Lifestyle changes like weight loss and exercise
- Procedures for carefully selected individuals
9. What are device-based therapies to prevent stroke?
For some people with AFib who can’t take long-term blood thinners, there’s a minimally invasive option that helps lower the risk of stroke. Doctors can implant a small device in the heart to seal off the left atrial appendage — the area where clots commonly form.
By closing off this part of the heart, the device helps prevent blood clots from escaping and causing a stroke. It’s placed through a catheter during a procedure that usually doesn’t require open-heart surgery and can be an alternative to lifelong use of anticoagulants.
10. What are rhythm control procedures for AFib?
Rhythm control therapies aim to restore a normal heartbeat in people with AFib. These treatments are often used when medications don’t work well or cause unwanted side effects.
One common option is catheter ablation, a minimally invasive procedure that uses thin wires to target and disable the heart tissue causing irregular rhythms. Traditional methods use heat (radiofrequency) or cold (cryoablation).
“This procedure may be part of a comprehensive treatment plan and is done only after carefully considering a patient’s situation,” Dr. Olson says.
A newer approach called pulsed field ablation (PFA) uses non-thermal electrical pulses to treat AFib more precisely, with less risk of damaging surrounding tissues. Both techniques are done through a catheter inserted into a blood vessel.
Scripps was the first health system in San Diego to offer catheter ablation and continues to lead in advanced rhythm control care.
Scripps is home to a team of medical professionals who are experts in diagnosing and treating abnormal heart rhythms, such as AFib, and in researching ways to treat cardiac arrhythmia.
Scripps is nationally recognized as a heart care leader and consistently ranked by U.S. News & World Report as one of America’s Best Hospitals for cardiology and heart surgery.