Understanding Atrial Fibrillation

AFib occurs when electrical signals in the heart become very rapid and disorganized. This causes the heart's upper chambers to contract irregularly (or quiver), making them unable to fully pump blood into the heart’s lower chambers. This may make it hard for the heart to pump enough oxygen-rich blood to the body.

The damage to the heart’s electrical signals is often caused by health conditions that affect the heart, such as high blood pressure or coronary heart disease. In some people, the cause of AFib may remain unknown.

Who’s at risk for AFib?

As you get older, your risk for AFib rises (most people develop AFib at age 65 and older), or if you have a family history of AFib. Other risk factors include:

High blood pressure.
A history of heart disease.
Having chronic conditions such as thyroid problems, diabetes, or asthma.
Sleep apnea.
Being an athlete.
Excessive drinking (5 alcoholic drinks in 2 hours for men or 4 drinks in 2 hours for women).

What are the signs and symptoms?

Not everyone with AFib will have signs or symptoms. But if they do, they may experience one or more of the following:

A “thumping” or “fluttering” feeling in the chest (also called palpitations).
Shortness of breath.
Weakness during exercise.
Tiredness.
Dizziness or feeling faint.
Confusion.

Keep a record of your symptoms. Note when they occur, what causes them to come on or go away, how long they last, and how often they happen. Also keep track of other medical conditions you may have and how they might affect your symptoms. Talk with your healthcare provider about any symptoms you may have.

Can AFib cause any health complications?

AFib can lead to other serious health problems including stroke and heart failure.

A stroke can happen because AFib can cause blood to stay in the atria (the upper chambers of the heart) too long, making it more likely to form a clot. The clot can then be pumped out of the heart and travel to the brain. Once there, it can block blood supply to an artery of the brain, causing a stroke. People with AFib are almost 5 times more likely to develop a stroke than those who do not have AFib.

Heart failure means the heart is not pumping enough blood to help your body function properly. AFib can lead to heart failure because the heart beats so fast that it never properly fills up with blood to pump out to the body. When that happens, blood can back up into the veins that carry oxygen-rich blood from the lungs to the heart. When AFib causes heart failure, the fluid in the lungs can cause fatigue and shortness of breath. What’s more, oxygen-rich blood is not being sent to the brain and other parts of the body. This causes physical and mental fatigue and reduces a person’s stamina. Fluid can also build up in the legs, ankles, and feet. This causes heart failure-related weight gain.

How is it diagnosed?

AFib is diagnosed based on medical history, physical exam, and the results from tests and procedures. Sometimes AFib does not have symptoms and it may be found during heart tests such as an EKG (electrocardiogram, which shows the heart’s electrical rhythm) that are done for other purposes. Other tests used to diagnose AFib include blood tests, chest X-ray, stress tests, Holter monitor to record the heart’s electrical activity, or an echocardiography (or echo).

If you think you have any of the symptoms of AFib, be sure to tell your healthcare provider or schedule a well-check visit.

How is AFib treated?

Depending on your health status, your treatment plan may include a healthier lifestyle, medication, surgery, or other medical procedures. It’s important that you also work with your healthcare provider to manage any other conditions that you may have (see the “Lifestyle changes” section below).

If you’ve been diagnosed with AFib, it’s important that you follow up regularly with your healthcare provider. He or she may work with you to help:

Bring your heartbeat to a more normal rhythm.
Manage your risk factors for stroke.
Decrease the risk of blood clots.
Prevent heart failure.

Are there lifestyle changes that can help to improve my AFib?

Your healthcare provider may recommend that you take steps to live a healthy lifestyle. Sometimes simple changes can help you manage AFib and reduce your risk for stroke. Talk with your healthcare provider about:

Limiting possible AFib triggers such as alcohol, caffeine, and stress.
Quitting smoking.
Eating heart-healthy foods.
Following an exercise plan.
Getting support. Include family and friends to help you manage your AFib. For example, help them to know the signs of stroke. Also ask them to help you cope with the condition, manage stress, and encourage you to stick to your treatment plan.

It’s important to understand AFib and to talk with your healthcare provider about how to manage it. Many people live a normal, active life with AFib—and what better way to do it than by staying healthy?

Medically reviewed by George H. Sands, MD, FAAN, FAHA, Senior Medical Director at Pfizer Inc.

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