Over the course of a normal lifespan, the heart will beat 2 to 3 billion times, rhythmically contracting nonstop to pump blood throughout your body. When it’s working well, you might not give the heart much thought. But when something’s amiss, it can have serious implications for your health.

Heart problems often trigger a common set of symptoms: shortness of breath, feeling tired, difficulty performing everyday activities, and palpitations—which feel as if the heart is pounding in the chest. These symptoms can be caused by a number of cardiac conditions, one of which is called atrial fibrillation, or AFib.

AFib is the most common type of irregular heart rhythm (also called arrhythmia). It affects an estimated 2.7 to 6.1 million people in the U.S., and causes about 450,000 hospitalizations each year.

AFib can affect people of any age, though it mostly occurs in people over 60. As the population grows older, the number of cases is expected to rise; experts estimate there will be 12.1 million cases in the U.S. by 2030.

While AFib is a serious condition, various treatments, including lifestyle modification, medications, and medical procedures can help.

“Atrial fibrillation is increasingly common in the U.S., and has important consequences for patients, including symptoms like palpitations, fatigue, and shortness of breath, as well as a higher risk of stroke and mortality,” says James Freeman, MD, MPH, MS, director of the Yale Atrial Fibrillation Program. “The good news is that we have a growing number of very effective treatments, including health behavior changes, rhythm medications, blood thinners, ablation procedures, and left atrial appendage occlusion procedures.”

AFib is a cardiac arrhythmia that interferes with how effectively the heart pumps blood throughout the body.

In a healthy heart, its four chambers—two upper atria and two lower ventricles—work together, contracting and pumping blood at a carefully controlled pace and rhythm.

The heart’s contractions are regulated by electrical signals generated by the sinoatrial node (the SA or sinus node), a part of the right atrium, the upper right chamber of the heart. In a heart that is working normally, the SA node generates an electrical signal. That signal stimulates the atria to contract and pump blood into the ventricles. The electrical signal travels down the heart and stimulates the ventricles to contract, causing them to pump blood to the lungs and the rest of the body.

In atrial fibrillation, however, electrical signals are generated from multiple areas of the atria, rather than solely from the SA node. These abnormal electrical impulses cause the atria to twitch and quiver rapidly and with a disordered, irregular rhythm. As a result, the atria do not contract fully, preventing them from efficiently pumping blood into the ventricles. Blood can pool in the atria, increasing the risk of blood clot formation and stroke. And because the upper and lower chambers of the heart do not contract in a coordinated pattern, the pumping of blood throughout the body is significantly impacted.

AFib often begins with short episodes of rapid, irregular heartbeats that go away on their own after a few days. But over time, the condition progresses, and these episodes become more frequent and longer lasting.

There are four main types of AFib, based on how long the condition lasts:

• Paroxysmal atrial fibrillation develops suddenly and resolves within 7 days of onset.
• Persistent atrial fibrillation is when AFib episodes last for over 7 days.
• Long-standing persistent atrial fibrillation is AFib that persists for 12 months or longer.
• Permanent atrial fibrillation describes AFib in which the heart’s rhythm remains irregular in spite of previous attempts to restore or maintain normal heart rhythm. At this stage, the doctor and patient jointly decide to stop trying to control the abnormal heart rhythm and AFib is permanent. Treatment instead focuses on lowering the heart rate in these patients.

Several factors and medical conditions are known to cause or increase the risk for AFib, including:

• Increasing age
• High blood pressure
• Cardiovascular disease (heart failure, coronary artery disease, valvular heart disease, rheumatic heart disease, cardiomyopathy)
• Obstructive sleep apnea
• Obesity
• Diabetes
• Chronic kidney disease
• Excessive alcohol consumption, including binge drinking
• Cigarette smoking
• Hyperthyroidism
• Family history of AFib
• Male sex

Previous heart surgery (in particular, risk is increased in the first few days following surgery)

AFib can cause a number of symptoms, including:

• Palpitations (sensation that heart is pounding, fluttering, skipping beats, or beating rapidly)
• Fatigue
• Shortness of breath
• Light-headedness
• Dizziness
• Weakness
• Rapid heartrate (100–160 or more beats per minute)
• Chest pain or discomfort
• Exercise intolerance (feeling excessively fatigued during exercise)
• Irregular pulse

However, some people who have AFib do not have any symptoms.

To diagnose AFib, your doctor will assess your medical history, conduct a physical exam, and run one or more diagnostic tests.

To obtain a medical history, your doctor may ask about symptoms, when they began, and whether you have any risk factors for AFib.

During the physical exam, although your doctor will check your pulse to see if there is an irregular heartbeat, diagnosis almost always requires an electrocardiogram, also known as an ECG or EKG (a test that measures the heart’s electoral activity).

If you are diagnosed with AFib, your doctor may also order an echocardiogram, or ultrasound of the heart. This imaging study can detect structural irregularities in the heart. (It’s important to note that bloodwork is usually necessary to determine the exact cause of AFib.)

Treatments for AFib aim to prevent stroke, restore normal heart rate or heart rhythm, reduce symptoms and/or stop the condition from worsening. They may include:

Lifestyle changes. Certain lifestyle changes can help control the abnormal rhythm and reduce the risk of complications from AFib. These changes may include eating a heart-healthy diet, exercising regularly, quitting smoking, maintaining a healthy weight, and keeping high blood pressure and cholesterol levels under control.

Medications:

• Blood thinners, such as warfarin, apixaban, dabigatran, edoxaban, and rivaroxaban, to prevent the formation of blood clots and lower the risk of stroke.
• Beta blockers, calcium channel blockers, or digoxin to slow the heart rate to within the normal range when patients have AFib episodes.
• Other antiarrhythmic drugs, such as amiodarone, flecainide, propafenone, sotalol, and dofetilide among others, to help restore a normal heart rhythm.

Medical and surgical procedures:

• Electrical cardioversion, a procedure in which an external defibrillator is used to deliver an electrical shock to the heart through electrode patches that are placed on the chest—or the chest and back. The shock, delivered at a precise moment in the heart’s beating cycle, can restore the heart to a normal rhythm.
• Catheter ablation, a minimally invasive procedure in which an electrophysiologist—a doctor who specializes in treating heart arrhythmias—inserts a catheter (a thin tube) into a vein or artery and maneuvers it through the blood vessel to the heart. The electrophysiologist uses a device at the tip of the catheter to deliver energy in the form of radiofrequency waves, lasers, cold temperatures, or electrical current to the areas of heart tissue involved in generating or conducting abnormal electrical signals that cause AFib. The energy ablates—or destroys—the heart tissue, which prevents it from generating or conducting electrical signals. Many patients can go home the same day or after a brief overnight stay. In many cases, catheter ablation can control AFib and durably restore normal rhythm.
  
  In late 2023 and early 2024, the Food and Drug Administration (FDA) approved two devices for pulsed field ablation for people with paroxysmal AFib. Pulsed field ablation is a type of catheter ablation in which rapid electrical pulses are used to destroy small areas of heart tissue. Traditional “thermal” catheter ablation often uses heat or cold temperatures to ablate heart tissue. In some cases, these ablation methods result in damage to nearby tissues, such as the esophagus and/or phrenic nerve (the nerve that controls the movement of the diaphragm and plays an essential role in breathing). Clinical trials have found that pulsed field ablation is as effective as traditional thermal ablation methods, may reduce the risk of damage to nearby tissue associated with traditional methods, and typically has a shorter procedure time.
  
  If all other treatments for AFib are ineffective in controlling heart rate or rhythm, a type of catheter ablation known as catheter ablation of the atrioventricular (AV) node may be an option. In this procedure, the electrophysiologist performs ablation of the AV node, a part of the heart involved in sending electrical signals from the atria to the ventricles, the two lower chambers of the heart. This AV node ablation stops electrical signals from moving from the atria to the ventricles. People who undergo an AV node ablation must have a permanent pacemaker implanted during the procedure. The pacemaker regulates the heart rate after AV node ablation.
• Surgical ablation, a procedure in which a cardiac surgeon accesses the heart through the chest and uses an ablation device to deliver energy—often radiofrequency or cold temperatures—to small areas of heart tissue. As with catheter ablation, the energy destroys areas of heart tissue, preventing it from generating or conducting the abnormal electrical signals that cause AFib. Surgical ablation may be performed via open-heart surgery (often as part of an open-heart procedure performed for another reason) or using minimally invasive techniques.
• Left atrial appendage closure, a minimally invasive procedure in which an electrophysiologist or interventional cardiologist uses a catheter to place a device into the left atrial appendage to seal it off and prevent blood clots from forming and traveling to the brain, causing stroke. The left atrial appendage is a small sac in the muscular wall of the left atrium (the left upper chamber) and the source of the blood clots that cause the vast majority of strokes in AFib. As a result, this procedure is very effective for stroke prevention and generally allows patients to come off blood thinners within a few months. Many patients will go home the same day or after a brief overnight stay.

Though AFib is serious condition, millions of people in the U.S. live with it. Timely treatment, regular monitoring of the heart, and appropriate lifestyle changes can help people who have AFib manage symptoms and live longer, healthier lives.

“The Yale Atrial Fibrillation program is a nationally and internationally recognized center of excellence for the treatment of patients with AFib,” says Dr. Freeman. “Our team of physicians, nurse practitioners, physician assistants, nurses, and technologists takes a comprehensive approach to treating AFib that is state-of-the-art and tailored to the needs of each patient. Our team also leads and participates in cutting-edge research on AFib, leading the field and bringing the most advanced treatments to our patients.”