What are the symptoms of atrial fibrillation (AFib)?

Diana Meeks
Diana Meeks on behalf of Sigma Nursing
Family Practitioner

Some people affected with chronic atrial fibrillation are symptom free. Others may have symptoms such as low blood pressure; a quick, irregular pulse; lightheadedness; or palpitations. Chest pain is a common symptom among older people, and some people in this age group may experience heart failure.

You would think it would be hard to miss if your heart suddenly started beating like it was doing an extended jazz drum solo, but you may not be bothered. However, you’re not alone if you feel fatigued, out of breath, have a fluttering heartbeat, pain in your chest, or are completely exhausted and unable to move. Take these symptoms seriously and get to a doctor ASAP.

Dr. Jose A. Nazari, MD
Cardiac Electrophysiologist

The most common symptom of atrial fibrillation is palpitations caused by an irregular heartbeat. But some people just feel miserable, tired, or short of breath, and they don't quite know why.

Dr. Mohammad E. Mortada, MD
Cardiologist (Heart Specialist)

The most common symptoms associated with atrial fibrillation (AF) include:

  • Tiredness - more than usual
  • Heart palpitations - feeling irregular, hard or fast beats in the chest (this may start and stop suddenly)
  • Dizziness, lightheadedness and sometimes fainting
  • Shortness of breath occurring at rest or with slight activity
  • Chest discomfort or pressure-like feeling in the chest

Not all people feel symptoms when they experience AF. About one person in five has no symptoms. For some, the symptoms may be mild, while others may have uncomfortable, severe or even frightening symptoms.

The most common type of abnormal heart rhythm is atrial fibrillation. Symptoms include a rapid heartbeat, heart palpitations, light-headedness, fatigue, shortness of breath and chest pain.

Atrial fibrillation, the most common type of serious arrhythmia (irregular heartbeat), is characterized by very fast, irregular electrical signals in the upper chambers of the heart called the atria. These electrical signals may travel through the atria at a rate of more than 300 per minute.

The walls of the atria quiver very quickly, making them pump blood ineffectively. The bottom chambers of the heart, called the ventricles, continue to contract and pump blood normally; however, they may do so in a rapid and irregular fashion.

When symptoms of atrial fibrillation occur, they may include palpitations, anxiety, dizziness, fainting or the feeling of nearly fainting, sweating, shortness of breath, and/or chest pain.

Dr. Douglas E. Severance, MD
Family Practitioner

The main symptoms of atrial fibrillation are heart palpitations, fluttering or pounding in your chest, a rapid heartbeat, an irregular pulse, difficulty catching your breath and/or dizziness. Yet, sometimes atrial fibrillation has no symptoms at all. You may be unaware that your heart is not beating in a normal pattern, especially if it has been occurring for some time. People with atrial fibrillation often live with the condition without being aware that their heart is not in a normal rhythm. Your doctor will listen to your heart and check your pulse. Your doctor may do an electrocardiogram (ECG, EKG) to confirm any suspicion that you have atrial fibrillation. These health checks may alert your doctor that you have an arrhythmia. If the ECG does not show an arrhythmia, the doctor may ask you to wear a Holter monitor or portable ECG that you will wear for 24 to 48 hours. This ECG will give your doctor information about your heart rhythm during this time period.

Joan Haizlip, MSN
Cardiologist (Heart Specialist)

The symptoms of atrial fibrillation (A Fib) are different for different people. You may feel nothing; some people with atrial fibrillation only find out when their doctor discovers it with an EKG.  Other symptoms include:

  • palpitations
  • shortness of breath
  • difficulty exercising
  • chest pain
  • dizziness
  • fatigue
Dr. Andrew J. Brenyo, MD
Cardiologist (Heart Specialist)

The most common symptom is a sense of fatigue accompanied by an irregular pulse. Classically, the symptoms of atrial fibrillation are palpitations or a sense of the heart skipping in the chest. In reality it is uncommon that patients will experience this symptom. The majority of atrial fibrillation is fully asymptomatic. Invasive monitoring studies have shown asymptomatic atrial fibrillation to be eight times more frequent than symptomatic atrial fibrillation. What we often see is exertion intolerance, shortness of breath when active, profound fatigue, and nausea generally associated with higher heart rates seen with paroxysms of atrial fibrillation. Through medical and ablative therapy, these symptoms can be addressed due to an associated reduction in paroxysmal episodes.

Dr. Joshua D. Stern, MD

The following is a list of most of the common symptoms of atrial fibrillation (AFib). Keep in mind, though, that some of these signs and symptoms are similar to ones you can experience when your heartbeat increases with vigorous physical exercise:

  • Fast heartbeat - usually over 140 beats per minute. You can take your own pulse by placing a finger on your wrist or neck. If you were exercising, wait a few minutes to see if your heartbeat goes back to your normal rate, which should be between 60 and 100 beats per minute
  • Light-headedness, which, in medical terminology, differs from dizziness. A person with light-headedness feels as if he/she is going to faint.
  • Dizziness - the feeling that you are spinning or moving
  • Confusion
  • Heart palpitations - a racing, uncomfortable sensation in the chest, or a flopping in the chest
  • Breathlessness
  • Weakness
  • Chest pains during physical exertion
  • Angina - chest pain or discomfort that occurs when the heart muscle does not get enough blood. Angina is more likely if the heartbeat is very fast and the heart is being put under a lot of strain.
  • Hypotension - low blood pressure
  • Heart failure - a condition in which the heart does not pump blood throughout the body efficiently.
  • Disorders of the heart muscle

If you have any of these symptoms or think you may have AF, contact your doctor and be tested. Of course, you may not have any signs or symptoms and still have atrial fibrillation, in which case the condition can only be detected during a routine medical examination or after a health problem.

Dr. Imran A. Niazi, MD
Cardiac Electrophysiologist

Most people with atrial fibrillation (AF) feel as if their heart is beating too fast or pounding; feeling it "jumping out of my chest!"is a common complaint. Others only feel their pulse to be irregular. Many people complain of fatigue and inability to exercise. Shortness of breath with exertion is also common. Finally, some people have no symptoms at all and cannot feel the difference between AF and normal rhythm.

People with atrial fibrillation often complain of heart palpitations, but it is possible that people may have no symptoms at all. Some may also complain of chest pain and may experience fainting episodes.

Some people with atrial fibrillation do not feel anything different. Others notice an abnormal feeling right away. If you have atrial fibrillation, you may feel a racing, uncomfortable, irregular heartbeat and a "flopping" in your chest. Dizziness, sweating, and chest pain or pressure can also occur. Other symptoms include shortness of breath, overall weakness, and the inability to exercise.

Here are some of the symptoms you may experience:

  • Irregular and rapid heartbeat
  • Heart palpitations or rapid thumping inside the chest
  • Dizziness, sweating and chest pain or pressure
  • Shortness of breath, anxiety
  • Tiring more easily when exercising
  • Fainting
Dr. Ronald M. Firth, MD
Family Practitioner

For some people, Afib doesn’t cause symptoms. For others, Afib can cause symptoms such as:

  • palpitations - a racing or irregular heartbeat
  • chest discomfort
  • shortness of breath - difficulty getting enough breath during normal activities or even at rest
  • tiredness or weakness
  • feeling dizzy, lightheaded, or confused

For some people, atrial fibrillation (Afib) doesn't cause symptoms. For others, Afib can cause symptoms such as:

  • Palpitations - a racing or irregular heartbeat
  • Chest discomfort
  • Shortness of breath - difficulty getting enough breath during normal activities or even at rest
  • Tiredness or weakness
  • Feeling dizzy, lightheaded or confused

Although some people experience no symptoms, common symptoms of atrial fibrillation include:

  • Palpitations (the heart feels like it is pounding or beating rapidly)
  • Light-headedness or dizziness
  • Shortness of breath
  • An uncomfortable feeling in the chest
  • Fatigue

Atrial fibrillation (AF) is the most common arrhythmia (abnormal heart rhythm) in the United States, with more than 150,000 new cases diagnosed each year. AF may produce a fast, irregular heartbeat that leads to palpitations, fatigue or shortness of breath. However, many people are unaware they have the condition until faced with serious health problems.

Unfortunately, some people only find out they have AF when they suffer a stroke, which is five times more likely in people with AF. Just as people should know if their blood pressure or cholesterol is high, they should know if they have AF so they can be treated for it.

Atrial fibrillation (AF) usually causes the ventricles to contract faster than normal. When this happens, the ventricles don't have enough time to fill completely with blood to pump to the lungs and body.
This inefficient pumping can cause signs and symptoms, such as:

  • Palpitations (feelings that your heart is skipping a beat, fluttering, or beating too hard or fast)
  • Shortness of breath
  • Weakness or difficulty exercising
  • Chest pain
  • Dizziness or fainting
  • Fatigue (tiredness)
  • Confusion

Atrial Fibrillation Complications
AF has two major complications—stroke and heart failure.

  • Stroke - During AF, the atria don't pump all of their blood to the ventricles. Some blood pools in the atria. When this happens, a blood clot (also called a thrombus) can form. If the clot breaks off and travels to the brain, it can cause a stroke. (A clot that forms in one part of the body and travels in the bloodstream to another part of the body is called an embolus.) Blood-thinning medicines to reduce the risk of stroke are a very important part of treatment for people who have AF.
  • Heart Failure - Heart failure occurs when the heart can't pump enough blood to meet the body's needs. AF can lead to heart failure because the ventricles are beating very fast and aren't able to properly fill with blood to pump out to the body. Fatigue and shortness of breath are common symptoms of heart failure. A buildup of fluid in the lungs causes these symptoms. Fluid also can build up in the feet, ankles, and legs, causing weight gain. Lifestyle changes, medicines, and sometimes special care (rarely, a mechanical heart pump or heart transplant) are the main treatments for heart failure.

This answer from the National Heart, Lung and Blood Institute has been reviewed and/or edited by Dr. William D. Knopf.

The symptoms of atrial fibrillation can vary, including palpitations, a sense of irregular heart rate, lightheadedness, dizziness, syncope (passing out), shortness of breath and fatigue.

Continue Learning about Atrial Fibrillation Symptoms

What do I tell my doctor about my symptoms of atrial fibrillation?
Donna Hill Howes, RNDonna Hill Howes, RN
If you have symptoms of atrial fibrillation, it's important to know what to tell your doctor at ...
More Answers
Should I talk to my doctor about my atrial fibrillation symptoms?
Honor Society of Nursing (STTI)Honor Society of Nursing (STTI)
Yes, you should talk to your doctor about your atrial fibrillation symptoms. Untreated atrial fibril...
More Answers
Not All Atrial Fibrillation Is the Same
Not All Atrial Fibrillation Is the Same
Know the Symptoms of Atrial Fibrillation
Know the Symptoms of Atrial Fibrillation

Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.