What Is Atrial Fibrillation?

Atrial fibrillation (also called AF or AFib) is a common heart rhythm disorder caused by an electrical system problem in the upper chambers (atria) of the heart. Cells in the atria send out extra electrical signals. These extra signals make the atria beat very quickly and unevenly.

When this happens, the atria beat so fast and unevenly that they may quiver instead of contract. If your atria don’t contract, they don’t move enough blood into the bottom part of your heart (ventricle).

Atrial fibrillation is a serious condition since it affects your heart’s ability to fill with blood normally. However, with treatment and close monitoring, it can be controlled.

Can Atrial Fibrillation Come and Go?

Some people have atrial fibrillation for a while, but then it goes away. Other people live with AFib every day.

More than two million people in the US have AFib, and about 160,000 new cases are diagnosed each year.

What Are the Symptoms of Atrial Fibrillation?

Common symptoms include palpitations (a fluttering heartbeat), dizziness, weakness or tiredness, chest pain or tightness, or shortness of breath. Sometimes patients will have very symptoms.

What Causes Atrial Fibrillation?

In many cases, doctors don’t know what causes atrial fibrillation. But certain risk factors may increase your chances of developing AFib. A risk factor is anything that increases your chances of developing a disease. Possible risk factors include the following:

Is AFib Dangerous?

On its own, having AFib usually isn’t life-threatening. But people with AFib are more likely to develop other related heart problems.

If you’ve been diagnosed with AFib, you may have a higher chance of developing other dangerous conditions like stroke or heart failure.


If you have AFib, the heart muscle doesn’t contract normally to force open the heart valves that pass blood from the atrium to the ventricle. Blood that isn’t kept moving can pool and form clots in your atria. These clots can move into other parts of your body and cause serious problems, such as a stroke. However, patients with Afib have higher chances of having a stoke even during periods when their heart is not in Afib.

Heart Failure or Heart Muscle Disease

Atrial fibrillation can be associated with a decline in heart function and worsening of heart failure symptoms. This means that people with AFib can have poor heart function along with symptoms of heart failure that get worse over time. Sometimes AFib can damage the heart muscle and change the normal electrical signals to the heart.

Treatment for Atrial Fibrillation

Multiple treatments for atrial fibrillation work together to prevent blood clots from forming, control heart rate, and restore a normal heart rhythm. The goal of treatment is to reduce your chances of having stroke or heart failure. Afib treatments also work to improve quality of life for patients.

Treatments include:

  • Blood-thinning medications; Warfarin (Coumadin®) is common, but there are newer medications that don't require routing monitoring (e.g., rivaroxaban, apixaban, dabigatran, edoxaban). Though all blood thinners increase your chances of bleeding, in many patients with Afib, this risk is balanced by the benefit of preventing stroke.
  • Heart rate medications; medications can either make your heart rate normal again or control your heart rate by reducing the number of electrical signals transmitted to your heart. Your heart can then pump more efficiently.
  • Lifestyle changes; too much caffeine, tobacco, or alcohol can cause arrhythmias. Your physician may ask you to stop taking/using substances that may cause Afib.
  • Cardioversion; this procedure "resets" your heart to make it beat normally again by sending a perfectly timed electrical shock to your heart. This causes all your heart cells to contract at the same time. All electrical activity in your heart stops for a brief moment. When your heart starts beating again, your heart rhythm returns back to normal. While this procedure can correct the heart's rhythm, it doesn't prevent the arrhythmia from coming back.
  • Cardiac catheter ablation; doctors use electrode catheters to ablate (destroy) small areas of heart tissue that have abnormal electrical pathways. In this procedure, doctors direct a catheter (a thin tube) through your blood vessels towards your heart and close to the area that has the abnormal pathway. Heating the tip of the catheter then destroys the small area of damaged heart tissue.

Learn more about cardiac ablation.


Doctor's Innovation Makes Life-Changing Surgery Available to Heart Patient

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