What are the Symptoms of Atrial Fibrillation (AFib or AF)?

The most common symptom: a quivering or fluttering heartbeat

Atrial fibrillation (AFib) is the most common type of irregular heartbeat. The abnormal firing of electrical impulses causes the atria (the top chambers in the heart) to quiver (or fibrillate). View an animation of atrial fibrillation.

Additional common symptoms of atrial fibrillation

Sometimes people with AFib have no symptoms and their condition is only detectable upon physical examination. Still, others may experience one or more of the following symptoms:

• General fatigue
• Rapid and irregular heartbeat
• Fluttering or “thumping” in the chest
• Dizziness
• Shortness of breath and anxiety
• Weakness
• Faintness or confusion
• Fatigue when exercising
• Sweating
• *Chest pain or pressure

*Chest pain or pressure is a medical emergency. You may be having a heart attack. Call 911 immediately.

Track your AFib symptoms (PDF)

Are there different types of AFib?

The symptoms are generally the same; however the duration of the AFib and underlying reasons for the condition help medical practitioners classify the type of AFib problems.

• Paroxysmal fibrillation is when the heart returns to a normal rhythm on its own, or with intervention, within 7 days of its start. People who have this type of AFib may have episodes only a few times a year or their symptoms may occur every day. These symptoms are very unpredictable and often can turn into a permanent form of atrial fibrillation.
• Persistent AFib is defined as an irregular rhythm that lasts for longer than 7 days. This type of atrial fibrillation will not return to normal sinus rhythm on its own and will require some form of treatment.
• Long-standing AFib is when the heart is consistently in an irregular rhythm that lasts longer than 12 months.
• Permanent AFib occurs when the condition lasts indefinitely and the patient and doctor have decided not to continue further attempts to restore normal rhythm.
• Nonvalvular AFib is atrial fibrillation not caused by a heart valve issue.

Over a period of time, paroxysmal fibrillation may become more frequent and longer lasting, sometimes leading to permanent or chronic AFib. All types of AFib can increase your risk of stroke. Even if you have no symptoms at all, you are nearly 5 times more likely to have a stroke than someone who doesn’t have atrial fibrillation.

How are heart attack symptoms different from AFib symptoms?

Fluttering and palpitations are key symptoms of AFib and is the key difference, but many heart problems have similar warning signs. If you think you may be having a heart attack, DON’T DELAY. Get emergency help by calling 911 immediately. A heart attack is a blockage of blood flow to the heart, often caused by a clot or build-up of plaque lodging in the coronary artery (a blood vessel that carries blood to part of the heart muscle). A heart attack can damage or destroy part of your heart muscle. Some heart attacks are sudden and intense — where no one doubts what's happening. But most heart attacks start slowly, with mild pain or discomfort. Often people affected aren't sure what's wrong and wait too long before getting help.

People living with AFib should know the symptoms of a stroke

As stated earlier, having atrial fibrillation can put you at an increased risk for stroke. Here are the warning signs that you should be aware of:

Heart Attack Warning Signs

Chest Discomfort

Most heart attacks involve discomfort in the center of the chest that lasts more than a few minutes, or that goes away and comes back. It can feel like uncomfortable pressure, squeezing, fullness or pain.

Discomfort in Other Areas of the Upper Body

Symptoms can include pain or discomfort in one or both arms, the back, neck, jaw or stomach.

Shortness of Breath

With or without chest discomfort.

Other Signs

May include breaking out in a cold sweat, nausea or lightheadedness.

Stroke Warning Signs

Spot a stroke F.A.S.T.:

• Face Drooping: Does one side of the face droop or is it numb? Ask the person to smile.
• Arm Weakness: Is one arm weak or numb? Ask the person to raise both arms. Does one arm drift downward?
• Speech Difficulty: Is speech slurred, are they unable to speak, or are they hard to understand? Ask the person to repeat a simple sentence, like "the sky is blue." Is the sentence repeated correctly?
• Time to call 911: If the person shows any of these symptoms, even if the symptoms go away, call 911 and get them to the hospital immediately.

Call 911 immediately if you notice one or more of these symptoms, even if they are temporary or seem to disappear.