Atrial Fibrillation (AFib)

You or your loved one may have been diagnosed with Atrial Fibrillation (AFib). You should know that you are not alone. There are many people around the world with this condition. It is the most common heart rhythm condition.

You or your loved one may have been diagnosed with Atrial Fibrillation. You should know that you are not alone. There are many people around the world with this condition. It is the most common heart rhythm condition.

This diagnosis comes with many questions and terms that may be hard to understand.

After reading the information below, we hope that you will feel more comfortable:

  • Taking an active role in your treatment decisions
  • Having open and honest conversations with your doctor about your concerns
The Basics of Atrial Fibrillation

Atrial Fibrillation, AFib for short, is a problem with how your heart beats. With AFib, your heart may beat too fast, switch back and forth from fast to slow, or skip beats. We call this type of heartbeat “irregular.” AFib may start suddenly and then stop on its own, or it may become a long-lasting problem. With AFib, your heart can’t pump blood out to your body in a normal way. AFib is an illness that can become worse if it’s not treated.

This type of irregular heartbeat gives you a higher risk of stroke and other heart problems.

In 2017, at least 37.5 million people were living with AFib around the world.

Sometimes the reason people get AFib is unknown. Other times, the system that signals the heart to beat is damaged. Different problems may cause this damage, with the most common being:

Heart-related problems such as:

  • High blood pressure
  • Coronary artery disease
  • Heart failure
  • Heart valve disease
  • Heart surgery (AFib is the most common
  • complication after heart surgery)

Other problems such as:

  • Sleep apnea
  • Thyroid disease
  • Lung disease or lung cancer
  • Drinking too much alcohol
  • Being seriously ill or having an infection
  • Some people are more likely to get AFib than
  • others. 

Some people are more likely to get AFib than others. You have a higher chance of getting AFib if:

  • You are older than 60
  • You smoke
  • You have diabetes
  • You are overweight
  • You have a family history of AFib
  • You exercise often and hard

Even people with healthy lifestyles who have no other medical problems can get AFib.

There are different types of AFib:

  • Paroxysmal AF -  AFib that occurs sometimes and then stops. AFib stops by itself and the heart returns to normal rhythm. AFib may last for seconds, minutes, hours, or days before the heart returns to its normal rhythm. People with this type of AFib usually have more symptoms than others. As the heart goes in and out of AFib, the pulse rate may change from slow to fast and back again in short periods of time.
  • Persistent AF - AFib that does not stop by itself. Medications or a special type of electrical shock (called cardioversion) is used to help the heart return to normal rhythm. If no treatment is given, the heart will stay out of rhythm.
  • Long standing persistent AF (formerly known as Permanent AF) - AFib that cannot be corrected. Medications and controlled electrical shock cannot help return the heart to normal rhythm.

Symptoms & Signs

The signs and symptoms of AFib are different from person to person. Some people with AFib feel no symptoms at all. They might not even know they have AFib or that there is a problem. Others can tell as soon as it happens. AFib symptoms can be bothersome and frightening.

Signs and symptoms include:

  • Feeling overtired or having little to no energy
  • Having a faster-than-normal heartbeat or a heartbeat that switches between fast and slow (irregular)
  • Having shortness of breath
  • Feeling like your heart is racing or pounding
  • Finding everyday exercises or activities harder than usual
  • Having chest pain, pressure, tightness, or discomfort
  • Feeling dizzy or lightheaded, or fainting

It’s important to see a doctor early if you have symptoms of AFib. Make an appointment if you notice something different or bothersome with your heartbeat


If your doctor thinks you may have AFib, the first thing they’ll do is ask you questions about your symptoms and listen for an irregular heartbeat through a stethoscope. They may also do tests to be sure of the diagnosis. The tests will help them figure out the reason for your irregular heartbeat and the best way to treat it.

A few tests can be done to check for an irregular heartbeat. An ECG or EKG for short, is a simple, painless test that is the most helpful in diagnosing AFib.

It can measure how fast your heart beats and the type of heartbeat you have. It can also measure the timing of the signals passing through your heart.

An ECG can be done in a doctor’s office. During this test, special stickers, called electrodes, are temporarily attached to your chest, arms, and legs. The electrodes pick up signals from your heart. The ECG test gives your doctor a picture of your heart’s activity.

Sometimes, the ECG done in the doctor’s office does not catch your AFib, and a test that lasts longer is needed. In this case, your doctor will ask you to wear a special monitor or a mobile device to keep track of your heart over a longer period of time.

There are several other tests that can be done to check for a fast or irregular heartbeat. Your doctor may order these tests if you are having signs or symptoms of a heart problem.

An ECG is a snapshot of your hear's electrical activity. Stickers (electrodes) are attached to your chest, arms, and legs. These electrodes measure the rate and rhythm of your heart.

A Holter monitor is a portable ECG. It can be worn for several days. Stickers (electrodes) are placed on your chest and are then connected to a small recording machine that is usually worn around the waist. It records the electrical activity of your heart for your doctor to review later.

A mobile cardiac monitor is worn for up to 30 days. It records your heart’s beat when it is in normal and abnormal rhythm. The results are automatically sent to your doctor. Your doctor uses this information to evaluate your symptoms to determine what is causing the abnormal rhythm.

An event monitor is a portable ECG that is used for patients who have an irregular heart rhythm every once in a while. You will carry the monitor with you at all times and attach it to your chest when you feel symptoms. This lets your doctor check your heart rhythm at the time of your symptoms.

An echocardiogram uses sound waves to produce images of your heart. This test allows your doctor to see how your heart muscle is moving and pumping blood.

A TTE is a standard non-invasive (no incisions or cuts) echocardiogram that gives your doctor a picture of your beating heart. An imaging device, called a transducer, gives off and reads sound waves. The imaging device records the sound waves bouncing off the walls and valves (echoes) in your heart. A computer then creates a video of your heart. This video can show the size of your heart, how well your heart is working, if the heart valves are working, and if there are blood clots in your heart.

A TEE is often done when the doctor needs to get a good picture of the back of your heart. To get a clear picture, a probe is placed down the esophagus (the tube that connects your mouth to your stomach). The esophagus passes right behind the heart. Once the probe is in place, it works the same way as a TTE described above.

Cardiac CT uses an X-ray machine and a computer to take clear, detailed pictures of the heart. During a cardiac CT, an X-ray machine will take pictures of your heart and chest. A computer will put the pictures together to make a three-dimensional (3D) picture of your heart and chest.

A cardiac MRI uses radio waves, magnets, and a computer to create pictures of your heart. Cardiac MRI creates detailed pictures of your heart as it is beating. The MRI will create snapshots as well as videos. Doctors use cardiac MRI to see the beating heart, the parts of the heart, and how the heart is working.


Once you are diagnosed with AFib, you and your doctor will make a treatment plan that is right for you. Your treatment plan may include being referred to a heart specialist, which might be a general cardiologist or a cardiologist that treats heart rhythm problems (electrophysiologist).

AFib can be treated in different ways. Treatments such as medications, non-surgical procedures, and surgery can slow down your heartbeat and bring it back to normal. Since AFib can cause blood clots to form in the heart, and the clots could then cause a stroke, patients are also often prescribed blood thinners to prevent blood clots from forming.

Terms & Resources

  • Watch this video to learn more about Atrial Fibrillation.
  • Learn more about the 2014 survey conducted by the Heart Rhythm Society and the National Stroke Association, on the impact of Atrial Fibrillation on patients and caregivers.

Keep Exploring

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