##  [Atrial Fibrillation (AFib)](/us-en/patients-and-caregivers/diseases/atrial-fibrillation "Atrial Fibrillation (AFib)") 

 Atrial fibrillation (AFib) is a common type of irregular heartbeat that begins in the upper chambers of the heart. Because the heart rhythm is fast and irregular, blood may not move as efficiently, which can increase the risk of serious complications, including stroke. Some people notice symptoms such as a racing heartbeat, fatigue or shortness of breath, while others may have no symptoms at all.1,2

## What Is Atrial Fibrillation (AFib)?



 



 - [Symptoms and Types](#tabsymptoms-and-types-36771)
- [Diagnosis and Testing](#tabdiagnosis-and-testing-36776)
- [Treatment and Support](#tabtreatment-and-support-36781)
 
AFib symptoms can vary widely. Some people feel a fluttering, pounding, racing or irregular heartbeat. Others may experience shortness of breath, dizziness, fatigue, weakness, chest discomfort or reduced ability to exercise.2 Some people have “silent” AFib with no noticeable symptoms, which means it may only be found during a routine exam or heart-monitoring test.1 Atrial flutter is another type of irregular heartbeat that, like AFib, begins in the upper chambers of the heart. Its rhythm pattern is usually more organized than AFib, but it can still increase the risk of stroke and other complications. AFib and atrial flutter can occur in the same person, and both may require evaluation for rhythm management and stroke prevention.3



 

 

AFib is typically diagnosed with an electrocardiogram, also called an ECG or EKG, which records the heart’s electrical activity. If AFib comes and goes, a short ECG may not capture it, so longer monitoring may be recommended. This can include a wearable monitor, event monitor or other heart rhythm tracking tools. Clinicians may also order blood tests or imaging to look for underlying causes.1 Because AFib can be silent, people should talk with a health care professional about their risk factors and whether additional evaluation may be appropriate.1



 

 

AFib care often focuses on several goals: managing symptoms, controlling heart rate, restoring or maintaining rhythm when appropriate, reducing stroke risk and addressing underlying health conditions. Treatment may include pharmacological therapies, lifestyle changes, procedures such as cardioversion or catheter ablation and stroke-prevention strategies.4 Stroke prevention can be challenging because it may involve balancing the risk of stroke against the risk of bleeding.1 People with AFib should ask about their personal stroke risk, bleeding risk, symptom burden, treatment goals and options for rhythm or rate control. They may also want to discuss blood pressure management, weight, alcohol intake, sleep apnea, diabetes and physical activity.1,4



 

 

 

 





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## AFib by the Numbers



 



 52M+ 

People Worldwide

####  In 2021, estimated global number affected by AFib or atrial flutter. 

 

 12.1M 

Projected US Cases

####  Projected US AFib cases by 2030, up from 5.2M in 2010. 

 

 5x 

Higher Stroke Risk

####  Approximate increased stroke risk in people with AFib. 

 

 







##  Featured Stories 

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###  What You Should Know About Your Stroke Risk 



 

 

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## 10 Frequently Asked Questions About AFib



 



 1. What is atrial fibrillation?

  

**Atrial fibrillation (AFib)** is a common type of irregular heartbeat. It occurs when the upper chambers of the heart beat in a fast, irregular way, which can disrupt normal blood flow. Some people feel symptoms like a racing heartbeat or fatigue, while others may not notice symptoms at all. AFib is important to identify because it can increase the risk of serious complications, including stroke.1,2

 ![Normal rhythm.](/us-en/sites/novartis_us/files/styles/crop_freeform/public/2026-09/afib-faq-rhythm-graphic-normal-v2.png.webp?itok=AVqBrSKr "Normal rhythm.")

 

*Normal rhythm.*

 ![AFib rhythm.](/us-en/sites/novartis_us/files/styles/crop_freeform/public/2026-09/afib-faq-rhythm-graphic-afib-v2.png.webp?itok=BdfprRxB "AFib rhythm.")

 

*AFib rhythm.*







 

 

 



 



 2. How common is AFib?

  

AFib is one of the most common heart rhythm disorders worldwide.1 In 2021 globally, it is estimated that more than 52 million people are affected by AFib or atrial flutter.5 In the United States, the number of people living with AFib is projected to more than double, from about 5.2 million in 2010 to 12.1 million by 2030.1 As populations age, AFib is expected to become an even larger public health challenge.1,5



 

 

 



 



 3. Why does AFib increase the risk of stroke?

  

In AFib, the heart’s irregular rhythm can cause blood to move less efficiently through the upper chambers of the heart. This may allow blood to pool and form clots. If a clot travels to the brain, it can cause an ischemic stroke, which is when a blood clot or fatty plaque blocks an artery that supplies blood to the brain.1,6 People with AFib have about a five-fold greater risk of stroke compared with people without AFib.2,6

 ![AFib rhythm clotting](/us-en/sites/novartis_us/files/styles/crop_freeform/public/2026-09/afib-faq-clotting-graphic-v2.png.webp?itok=YX0XOXAs "AFib rhythm clotting")

 



 

 

 



 



 4. What are the symptoms of AFib?

  

AFib symptoms can vary widely. Some people feel a fluttering, pounding, racing, or irregular heartbeat. Others may experience shortness of breath, dizziness, fatigue, weakness, chest discomfort, or reduced ability to exercise.2 Some people have “silent” AFib with no noticeable symptoms, which means it may only be found during a routine exam or heart-monitoring test.1



 

 

 



 



 5. What is atrial flutter, and how is it related to AFib?

  

**Atrial flutter** is another type of irregular heartbeat that, like AFib, begins in the upper chambers of the heart. The rhythm pattern is usually more organized than AFib, but it can still increase the risk of stroke and other complications. AFib and atrial flutter can occur in the same person, and both may require evaluation for rhythm management and stroke prevention.3



 

 

 



 



 6. Who is at higher risk of developing AFib?

  

AFib becomes more common with age, but several health factors can increase risk. These include high blood pressure, heart disease, heart failure, diabetes, obesity, sleep apnea, thyroid disease, kidney disease, and heavy alcohol use.1,5 Many people with AFib also have other medical conditions, which can make treatment decisions more complex.1



 

 

 



 



 7. How is AFib diagnosed?

  

AFib is typically diagnosed with an **electrocardiogram**, also called an **ECG or EKG**, which records the heart’s electrical activity. If AFib comes and goes, a short ECG may not capture it, so longer monitoring may be recommended. This can include a wearable monitor, event monitor, or other heart rhythm tracking tools. Clinicians may also order blood tests or imaging to look for underlying causes.1,4



 

 

 



 



 8. How is AFib treated?

  

AFib care often focuses on several goals: managing symptoms, controlling heart rate, restoring or maintaining rhythm when appropriate, reducing stroke risk, and addressing underlying health conditions. Treatment may include medications, lifestyle changes, procedures such as cardioversion or catheter ablation, and stroke-prevention strategies. The best approach depends on a person’s symptoms, medical history, stroke risk, bleeding risk, and overall health.1,4



 

 

 



 



 9. Why can stroke prevention in AFib be challenging?

  

Stroke prevention is a major part of AFib care, but it can involve balancing the risk of stroke against the risk of bleeding.1,7 Anticoagulants, including **direct oral anticoagulants (DOACs)**, are important options for many patients, but some people may be considered unsuitable for them because of high bleeding risk, prior bleeding, advanced age, kidney or liver issues, interactions with other medicines, or other complex health factors.1,6,7 Some studies estimate that more than half of high-risk AFib or atrial flutter patients are untreated; among those treated, up to one-third may receive suboptimal anticoagulant therapy due to bleeding risk and common coexisting health issues.7,8



 

 

 



 



 10. What should someone with AFib discuss with their health care professional?

  

People with AFib should ask about their personal stroke risk, bleeding risk, symptom burden, treatment goals, and options for rhythm or rate control. They may also want to discuss lifestyle factors such as blood pressure management, weight, alcohol intake, sleep apnea, diabetes, and physical activity.1,4 Anyone with symptoms such as chest pain, fainting, severe shortness of breath, sudden weakness, trouble speaking, confusion, or vision changes should seek urgent medical attention.2