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What is Atrial Fibrillation?


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Atrial fibrillation, sometimes called AFib or AF, happens when the upper chambers of your heart beat too fast. Some people feel fluttering in their chest, while others can feel like their heart is racing and they can’t get enough air. Other people may exhibit fatigue and tiredness with AFib. Some people report no symptoms.

The heart is made up of four areas called chambers. The two upper chambers are the atria. AFib happens when your atria shake or quiver and do not beat in time with the rest of your heart. This causes your heart to not work as effectively. Because the atria do not contract normally, the blood flow in the atria may be poor and lead to formation of a blood clot; if the blood clot travels to your brain, this causes a stroke. AFib is a major cause of stroke in the United States.

For patients diagnosed with atrial fibrillation, doctors study your heart to learn why you have AFib, so they can customize the best treatment for you.

Atrial Fibrillation Risk Factors

Atrial fibrillation can be caused by a variety of conditions, but it can also develop if you have no risk factors at all.

Risk factors for AFib include:

Age – Typically, the older you are, the higher your risk for AFib. Young adults can develop Afib although older adults have higher likelihood of developing Afib.

Athleticism – Athletes may experience AFib. Exercise is in general very good for the heart. In rare cases when athletes train for more than 8-10 hours/week, they may develop Afib.

Arrhythmias – Other abnormal heart rhythm problems can cause AFib. Supraventricular tachycardia (SVT) is an abnormal rapid heart beat and this can also result in AFib.

Chronic illness – Conditions such as diabetes, high blood pressure, and sleep apnea are associated with AFib. Talk with your primary care provider to see if you are at risk.

Drinking alcohol – Binge drinking (five drinks for men, or four drinks for women) can cause an acute episode of AFib. Chronic alcohol use can also lead to chronic or recurring Afib. Even one drink per day increases the likelihood of developing AFib. For patients with a history of AFib, studies have shown greater likelihood of recurrent AFib following one alcoholic beverage.

Family history – If you have a family member who has AFib, you may be at higher risk for developing the condition.

Heart disease – This includes valve conditions, thickened heart muscle (hypertrophic cardiomyopathy), sudden reduced blood flow to the heart (acute coronary syndrome), extra electrical pathways between the upper and lower heart chambers (Wolff-Parkinson-White syndrome), or if you had a heart attack in the past, or previous heart surgery.

Obesity – Being overweight is associated with AFib.

Types of Atrial Fibrillation

There are four types of AFib:

  • Paroxysmal – This type of AFib starts and stops on its own. Episodes can last from several minutes up to a day or two. Some people don’t feel it happen, while others have very strong symptoms.
  • Persistent – An irregular heartbeat that lasts for a week or more.
  • Long-term persistent – AFib that lasts for a year or more and doesn’t go away on its own.
  • Permanent atrial fibrillation – If the heart doesn’t return to a normal beat after trying treatment and medication, it is considered permanent.

How Atrial Fibrillation is Diagnosed

If your physician suspects you have atrial fibrillation, they will work with you to make a correct diagnosis.

History – Your physician will start by asking about your diet and activity. Also, family history and other symptoms you might have will be important to note.

Exam – Your physician will give you a thorough heart and lung exam. This involves listening to your heart and lungs with a stethoscope. The exam will also include checking your feet and legs for swelling, taking your blood pressure, and checking your blood for unusual thyroid hormone levels.

Testing – Your physician may order several tests for your heart to check for AFib:

  • An electrocardiogram (ECG) to record the electrical activity in your heart.
  • Blood tests to make sure something else isn’t causing your AFib, such as thyroid disease.
  • An echocardiogram may be performed to look at your heart to see if there are any abnormalities that may be causing Afib.
  • You may be asked to wear a heart monitor from one day up to a month. Some patients may be asked to use a consumer ECG device (i.e. iWatch, Kardia, etc) which can record and store a limited ECG on their smartphones.

If necessary, your physician may ask you to have other testing to get more detailed information on how your heart is working.

Atrial Fibrillation Treatments

UHealth has a wide range of treatment options for patients with heart rhythm issues.

Often, AFib can be initially treated by lifestyle changes or risk-factor modification. Managing chronic conditions such as obesity, diabetes, high blood pressure, and sleep apnea is key to controlling atrial fibrillation. Also, limiting or abstaining from alcohol can improve atrial fibrillation.

Including lifestyle changes with the following medical treatments has been shown to be helpful in improving AFib:

Non-Surgical Treatments


Ablation uses heat, called radiofrequency, or freezing called cryotherapy, to interrupt the pathways that cause atrial fibrillation. Your doctor will use a catheter, which is a small tube. The catheter will enter your body through a vein in your leg. Using a form of X-ray and special 3D mapping equipment to guide them, your doctor will navigate through your vein and into your heart. Then, they will either use heat or cold to treat the area of your heart that is causing the AFib.

In general, ablation therapy has been shown to be superior to medication therapy in patients with AFib. Sometimes, patients may need both ablation therapy and medications. Depending on your type of AFib, the duration of time you have had AFib, your age and the presence of other medical conditions, your physician can let you know if ablation therapy is for you.

Electrical Cardioversion

Electrical cardioversion uses pads adhered to the skin on your chest. Physicians send an electric shock through the pads and into your heart to make it return to a normal heartbeat.

Cardioversion resets the heart back to normal rhythm but does nothing to prevent recurrent AFib. Most patients who undergo cardioversion will require strong medications to attempt to prevent recurrence of AFib.


Medications can be used to control AFib. Your physician could recommend medication to prevent blood clots and/or specific medications that will help control your heartbeat.

Surgical Treatments

Surgery is sometimes necessary to get your heart beating correctly.

At UHealth, our cardiologists are experienced, skilled, and knowledgeable in the best treatments for atrial fibrillation.

MAZE Procedure

If you had ablation in the past, but your AFib returned, or you are having cardiac surgery for another reason, your physician may recommend a MAZE procedure. Whenever possible, this procedure is minimally invasive. The surgeon uses either incisions or ablation (radiofrequency or cryotherapy) to prevent AFib.

Re-Ablation of Arrhythmias Related to Past AFib Catheter Ablation

Scar tissue from a past catheter ablation can cause new atrial arrhythmias months or years later. Our catheter ablation techniques for AFib minimize occurrences of new arrhythmias. However, if you had AFib ablations and experience new atrial arrhythmias, we have experience with re-ablation, as well as opportunities to participate in medical studies, providing you with the best treatment options available.

Stroke Prevention

Atrial fibrillation can cause blood to pool in the left upper chamber of the heart. That area is the left atrial appendage (LAA). This pooling can cause clots to form and travel through the bloodstream, which might cause a stroke. If you have AFib and are considered at risk for stroke, you may need medication to thin your blood to prevent clots. If you cannot take these medications due to bleeding problems, we offer a minimally invasive surgical option. It is a device called the Watchman, which is implanted to close off the LAA to lower your risk of a stroke.

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