Overview of Atrial Fibrillation
This is an overview of Atrial Fibrillation, an introduction to A-Fib concepts, terminology and facts about Atrial Fibrillation. We’ll address the following topics:
• A-Fib―The Emerging Epidemic
• What is A-Fib?
• The types of A-Fib
• How serious an illness is A-Fib?
• How do you get A-Fib? What causes or triggers it?
• Treatments for A-Fib
• The Wrap Up
• Additional Reading
A-Fib—an Emerging Epidemic
It’s estimated at least 5.1 million people in the U.S. have A-Fib with 6 million in Europe and 8 million in China. By the year 2050, the number will be 5–16 million in the United States and more than 1 million in Japan. A-Fib contributes to more than 80,000 deaths annually. In the U.S., people over 40 have a one-in-four lifetime risk of developing A-Fib. Worldwide, it’s estimated 71–142 million suffer with Atrial Fibrillation. And in addition to being dangerous, A-Fib reduces our quality of life. It’s hard to live with a sick heart.
A-Fib is the most common heart arrhythmia and affects 2-4% of the general population. Over 45 million people worldwide have A-Fib. In 2020 approximately 2.1 million Americans under 65 will be diagnosed with A-Fib. In 2010 there were 1.2 million new cases of Atrial Fibrillation in the US. It’s estimated that in 2030 this figure will double to 2.6 million new cases each year.
A-Fib has rightly been called an epidemic. “One of eight of us will develop A-Fib, if we live long enough.” One of the most disturbing, scary statistics is that “14% of people diagnosed with A-Fib will pass away within one month of diagnosis.” In another study of people 65 or older, being diagnosed with A-Fib means you have a one-in-four chance of dying within the next year. The 5-year survival rate for A-Fib would rank number 11 if compared to a list of the 25 most deadly cancers. A-Fib is much more lethal in women than in men (McCarthy, Journal or Clinical Medicine, 2021).
A-Fib adds $26 billion to our country’s healthcare costs in one year.
What is A-Fib?

Normal heart showing the four chambers, AV node and Sinus Node.
In Atrial Fibrillation (A-Fib) the upper part of your heart beats (quivers) faster than the rest of your heart.
If you could look inside your chest, the top part of your heart would be shaking like Jell-O or beating more rapidly than the lower section of your heart. You feel an uncomfortable flutter in your chest or like your heart is going to jump out of your ribs or that your heart is “flip-flopping around.”
Your pulse is irregular and/or more rapid than normal. Someone described their A-Fib as “…like a motor idling too fast in my chest.” Or “like I had a maniacal bass drummer hidden away in my chest.”
SYMPTOMS OF A-FIB
You may have one or more of the following symptoms: you may feel lightheaded (fainting), very tired, have shortness of breath, sweating and chest pain, swelling in your legs, exercise intolerance (you can’t exercise like you used to), an embarrassing urgent need to pee.…and you may feel unsettled, frightened and anxious. You may feel like your brain isn’t working right, that at work you can’t cut it any more. Or perhaps you have few or no symptoms, and were surprised when the doctor said, “You have Atrial Fibrillation”.
The most common symptom of people in Persistent A-Fib is fatigue.
How your Heart Works
Somewhere in your heart extra electrical signals are being generated which causes the top part of your heart (the atria) to contract and quiver rapidly and irregularly (fibrillate) like a bag of worms. The atria can contract as many as 300-600 times a minute.
Your whole heart, however, does not beat 300-600 times per minute. Your heart is a muscular pump divided into four chambers―two atria located on the top and two ventricles on the bottom.
VIDEO 1: Animations of normal beating heart and a heart in atrial fibrillation. Click on image to see animation of a normal beating heart; Then use the ‘Select a condition’ at the bottom right of the page to select Atrial Fibrillation to see the heart beating in A-Fib.
Normally, each heartbeat starts at the top of the right atrium where a specialized group of cells called the Sinus Node generates an electrical signal that travels down a single electrical road called the AV Node (the natural pacemaker of the heart) that connects the atria to the ventricles below. This electrical signal causes the heart to beat. (The Autonomic Nervous System [ANS].}
First, the atria contract, pumping blood into the ventricles. Then, a fraction of a second later, the ventricles contract sending blood throughout the body. Normally the heart beats at 60-100 times per minute. When a doctor or nurse takes your pulse, he/she is counting contractions of your ventricles.
In A-Fib, electrical signals from other parts of the heart disrupt your heart’s normal rhythm and cause the atria to beat or quiver rapidly on their own, 300-600 beats per minute.
Below is a graphic representation of your beating heart: on top is an ECG of a normal heart beat (normal sinus rhythm); notice the regular pattern. Below it is an ECG of a heart in Atrial Fibrillation. Notice the irregular and erratic pattern.

© Patti J. Ryan and A-Fib, Inc
However, only a small number of these atrial beats make it through the AV Node which acts like a gate to the ventricles. This is fortunate, because you couldn’t live with a heartbeat that rapid. But some A-Fib beats do make it through the AV Node and make your whole heart beat irregularly and/or faster than normal.
TYPES OF A-FIB
There are three types of Atrial Fibrillation. In casual usage you may hear the three types of A-Fib described as occasional, persistent, and permanent or chronic A-Fib. Your doctor, however, may use one of the following medical terms:
• Paroxysmal: (pronounced par-ok-SIZ-mal) describes episodes that stop on their own, and last anywhere from seconds or minutes, to hours or up to a week
• Persistent: episodes which last more than a week; or episodes lasting less than a week but only stopped by cardioversion
• Long-standing Persistent: a type of Persistent A-Fib that lasts longer than one year; (formerly called Chronic or Permanent)
Note: the terms Paroxysmal and Persistent are not mutually exclusive. You may have several episodes of paroxysmal A-Fib and occasional persistent A-Fib, or the reverse. Your A-Fib is called by whichever occurs most often.
Atrial Flutter (A-Flutter)
Like in A-Fib, extra electrical signals are generated in your heart which make the atria contract faster than the ventricles. But in Atrial Flutter, your heart beats in an organized, predictable pattern. (In Atrial Fibrillation the atria beat chaotically and irregularly.) You may consider Atrial Flutter as a more regular, organized variety of A-Fib.
A-Flutter often, but not always, originates in the right atrium. Whereas A-Fib usually comes from the left atrium. (Someone with Flutter often has A-Fib potentials lurking in the left atrium or the Flutter is a precursor to A-Fib.)
Though this is a controversial subject, anyone getting a Flutter-only catheter ablation should discuss with their EP about also having a left atrium A-Fib ablation at the same time. A thorough left atrium ablation will document whether or not you have PV and non-PV A-Fib potentials and will isolate them from causing A-Fib. The controversy arises because many EPs, working on the principle of doing no harm, will not perform a left atrium ablation unless there is documented Atrial Fibrillation in addition to the Flutter.
If you are on a table in the EP lab and the EP is already inside your heart doing a right atrium Flutter ablation, it takes relatively little extra effort to get to the left atrium.
How Serious An Illness is A-Fib?
Some A-Fib patients may develop an extremely rapid, irregular heart rate which can be life threatening. A very rapid, irregular heart rate can strain your heart, reduce your circulation to dangerous levels, and make you feel like you’re going to faint from lack of oxygen.
Increased Risk of Stroke
If you have A-Fib, just how sick are you? A-Fib may feel weird and can be very frightening, but an attack of A-Fib by itself usually isn’t life threatening. The biggest danger from A-Fib is stroke. Because your heart isn’t pumping out properly, blood can pool in your atria, particularly in the ‘Left Atrial Appendage’. Blood clots can form and travel to the brain causing stroke.
If you have A-Fib and aren’t being treated by a doctor, you are five-to-six times more likely to have a stroke than the general population.
Researchers estimate that 35% of patients with A-Fib will suffer a stroke (unless treated). A-Fib is responsible for up to 25% of all strokes, or 140,000 strokes annually. Each year, about 8% of people with untreated A-Fib have a stroke.
(There are two main types of stroke. An “ischemic” stroke is a clot in a narrow blood vessel and is the kind that often occurs in A-Fib. Almost 85% of strokes are ischemic. A “hemorrhagic” stroke occurs when a blood vessel ruptures and leaks blood into the brain.)
An A-Fib stroke is worse than other causes of stroke. Half of all strokes associated with atrial fibrillation are major and disabling. Of A-Fib stroke patients, 23% die and 44% suffer significant neurologic damage. This compares to only an 8% mortality rate from other causes of stroke.
VIDEO 2: Atrial Fibrillation-Clot Formation & Stroke Risks; Animation showing how A-Fib clots can form and travel to the brain causing an ischemic stroke. (1:39) Uploaded by Thrombosis Adviser.
Strokes in women are more disabling than in men. There is also a danger of “silent” A-Fib strokes where stroke effects aren’t evident but may appear like attention deficit, forgetfulness, and senile dementia. Silent A-Fib is common.
More than a half-million Americans every year have an ischemic stroke or clot, but at least a quarter of these cases have no apparent underlying cause. Studies indicate that many of these strokes of unknown origin may come from Atrial Fibrillation. Up to 30%−50% of A-Fib patients are unaware they have A-Fib. Of those who suffered an A-Fib stroke, 25% had no prior diagnosis of A-Fib.
Talk To Your Doctor About Anticoagulants
If you have A-Fib, it’s most important to talk to your doctor about taking an anticoagulant like warfarin (Coumadin), or the newer anticoagulants dabigatran (Pradaxa), rivaroxaban (Xarelto), apixaban (Eliquis) or edoxaban (Savaysa) to help prevent these clots from forming. (Aspirin is less effective than Coumadin or the newer anticoagulants and is no longer recommended in today’s guidelines.)
Warfarin, the most prescribed anticoagulant, reduces the risk of stroke by 60% to 70% in A-Fib patients but is not an absolute guarantee one will never have an A-Fib stroke. President Nixon, for example, was on warfarin for years when he developed an A-Fib blood clot that dislodged from his heart and traveled to his brain, causing a massive stroke which killed him.
Risk of Bleeding From Anticoagulants
Anticoagulants are not like taking vitamins. Be aware that the anticoagulant warfarin has a 1.8% annual risk of life-threatening bleeding. Anticoagulants may prevent an A-Fib (ischemic) stroke while somewhat increasing one’s chances of a bleeding (hemorrhagic) stroke, particularly among the elderly.
As Thomas J. Moore of the Institute for Safe Medical Practices points out, “Anticoagulation treatment for people with A-Fib ranks as one of the highest risk treatments in older Americans…More than 15% of older patients treated with blood thinners for 1 year have bleeding.” In a 2011 study, 48.8% of all adverse drug events involved anticoagulants (Budnitz. Am Journal of Medicine, 2011).
Added June 15, 2022: “About one-quarter of older adults (over 65) on an anticoagulant who develop a brain bleed will die as a result, versus 9% of elderly patients who are not on anticoagulant therapy.” (Bottom Line Personal, Volume 43, Number 11, June 1, 2022. p. 8.)
Warfarin and most other anticoagulants are a trade-off for most patients. The danger of having an A-Fib stroke usually outweighs the risk of a bleeding (hemorrhagic) stroke or other side effects due to taking anticoagulants.
Some with A-Fib may not need anticoagulants at all. If you are young, active, and have an otherwise normal heart, you and your doctor may decide your A-Fib stroke risk is low, and you don’t need to be taking an anticoagulant.
A-Fib Damages Your Heart, Brain and Other Organs
If you have A-Fib, the upper parts of your heart (the atria) aren’t pumping enough blood into the lower chambers of your heart (the ventricles). It’s estimated that this reduces the amount of blood flowing to your brain and the rest of your body by about 15%-30%. A-Fib eliminates essentially all contractility of the Left Atrium.
You may not be getting enough blood to your brain and other organs which may cause weakness, fatigue, dizziness, fainting spells, swelling of the legs, shortness of breath, reduced mental abilities (brain fog), cognative decline, and brain damage. MRI studies of the brain show that nearly half of A-Fib patients have visible signs of brain damage in the form of brain lesions, even if they’ve never had a stroke. Others often have brain volume loss (brain shrinkage) and small patterns of brain injury called “white matter disease.”
Recent studies indicate that A-Fib reduces mental abilities and may lead to dementia and to heart failure.
Patients with A-Fib are 44% more likely to develop dementia. In A-Fib your brain may actually shrink because of reduced blood flow and oxygen. In one study, 40% of people with A-Fib had visible brain damage on an MRI.
Of patients suffering from A-Fib, 20%–50% develop heart failure (congestive heart failure). They are also at greater risk of myocardial infarction (heart attack), venous thromboembolism, and dementia.
Over time a very fast heart rates can strain the heart and cause a heart attack. Inefficient atrial pumping puts an added burden on the ventricles. Prolonged A-Fib episodes may stretch and weaken the heart muscle. A-Fib nearly doubles your chances of death. The mortality rate from atrial fibrillation (as either the primary or an underlying cause of death) has been increasing for more than two decades.
A-Fib often changes or “remodels” your heart. Your left atrium (LA) tends to expand, stretch, dilate and weaken the LA muscles. Your ejection fraction (how well your heart is pumping out blood) tends to decrease. A-Fib produces fibrosis (collagen and scarring in the heart). Fibrotic tissue is scarred, immobile, basically dead tissue with reduced or no blood flow and no transport function. It results in a loss of atrial muscle mass. (For more, see my article: A-Fib Produces Fibrosis.)
Over time it makes the heart stiff, less flexible and weak, overworks the heart, reduces pumping efficiency and leads to other heart problems. Your Left Atrium essentially stops contracting and pumping. Your heart also remodels electrically. A-Fib attacks tend to become longer and occur more often. A-Fib is usually a progressive disease.
[Editor’s comment: Please weigh the above statements carefully; I don’t want to create unwarranted fear.]
PSYCHOLOGICAL AND EMOTIONAL EFFECTS
Your first A-Fib attack is a shock. Something has gone terribly wrong with your heart. There’s the constant threat, fear and anxiety of an ever-possible A-Fib attack, the sense of sickness, the feelings of depression and impending doom.
A-Fib can deeply affect your state of mind and emotional well-being. Research suggests that psychological distress is present in a substantial portion of A-Fib patients and is related to greater A-Fib symptom severity, diminished quality of life, and adverse outcomes. Studies show that patients with paroxysmal A-Fib show signs of depression, sleeping disorders and low levels of physical activity.
Anxiety by itself can produce physical symptoms such as gastrointestinal distress, sleep issues, shortness of breath, exhaustion, muscle aches, shaking and trembling, sweaty palms, difficulty swallowing, a racing heart like in A-Fib, getting colds frequently because of a depressed immune system.
Sometimes there’s a lack of understanding from your family, friends, even from your doctor. And the sense of helplessness and lack of control, the worry about what A-Fib (and all these drugs you have to take) is doing to your heart and body. There’s the mood swings and the need to cry (sometimes worsened by the drugs one has to take)—these are all effects A-Fib can have both on your state of mind and on your social interactions.
On top of all this, your A-Fib can also affect your family, friends and colleagues (See Max Jusila’s personal A-Fib story “A-Fib Was Devastating“). Anxiety is the most common effect of A-Fib.
At A-Fib.com, we will give you an understanding of A-Fib and hopefully a sense of control. You will learn what A-Fib is and how to fix it. As terrible as A-Fib makes you feel, it’s a heart problem that’s the easiest to fix (unlike most other heart problems).
Did you recognize any of your symptoms in the above paragraph? Just acknowledging you have some or all of these symptoms is a step in the right direction.
But you may need more than this web site to deal with the psychological and emotional effects of A-Fib. Don’t be scared or ashamed to admit how A-Fib makes you feel (especially if you’re a guy). There’s nothing wrong with seeking counseling and medical help for how A-Fib affects your psyche. Your psyche is just as important as your physical heart. (See Jay Teresi’s story “Anxiety the Greatest Challenge” and Kelly Teresi’s story “A Young Wife Copes with Husband’s A-Fib” in my book, Beat Your A-Fib, pages 101-105.)
And be aware that your heart doctor may not be of much help. Your doctors are often so focused on dealing with your physical symptoms and getting you cured that they often don’t recognize or acknowledge how A-Fib affects your psyche and your quality of life. And they aren’t trained or often have little effective experience in dealing with the psychological and emotional aspect of A-Fib.
Studies show that physicians rate their patients’ health-related quality of life higher than their patients do, both for the mental and the physical component score. (I have yet to go to a medical conference on A-Fib where the emotional and psychological effects of A-Fib are even mentioned, let alone protocols discussed and developed to deal with them.)
And you need to recognize that A-Fib can have significant consequences on your social interactions, with your family, friends and colleagues. Sometimes family and friends, and even your doctor, may not understand what you are going through—that A-Fib has a psychological component in addition to the physical.
A-Fib isn’t like having a broken leg. To your significant others, you may look normal. Sit down with your family, friends, especially with your work colleagues and explain to them what A-Fib does to you. But realize that many will never understand the suffering A-Fib causes. (I fantasize about being able to give people a 10 second shot of A-Fib so that they [especially doctors] could feel what A-Fib is like). (Also see our article: Seven Ways to Cope With Your A-Fib Fear and Anxiety)
Would you be helped by talking with or emailing people who have been through the A-Fib ordeal? A list of A-Fib Support Volunteers is available under Resources and Links. Having someone you can turn to for advice, emotional support, and a sense of hope that you can be cured, may bring you peace of mind. It helps to have someone who has “been there” and is there for you.
These volunteers have gone through a lot to be cured of A-Fib, and have been helped along the way. They want to return the favor by offering you support and hope.
A-FIB REMODELS YOUR HEART AND IS A PROGRESSIVE DISEASE
It’s important to be treated as reasonably soon as possible.
In a process called “remodeling,” your heart actually changes if you have A-Fib long enough. The fast, abnormal rhythm in your atria causes electrical changes and enlarges your atria. Your heart develops fibrosis, the formation of fibrous tissue in the heart.
Your A-Fib episodes become more frequent and longer, often leading to continuous (Chronic) A-Fib. In the famous Framingham Heart Study, 25%-40% of people with A-Fib went on to develop continuous “persistent” A-Fib. In a study of 5,000+ A-Fib patients, 54% of those on rate control meds went into permanent “persistent” A-Fib in one year.
However, some people never progress to more serious A-Fib stages.
But even with Chronic A-Fib, people have been cured, and this remodeling of the heart partially or almost completely reversed.
But don’t delay! The longer you wait to be treated, the worse your A-Fib could get. (If you’ve had A-Fib for six weeks, your A-Fib probably hasn’t progressed very much. But if you’ve had A-Fib for six years, you should get treated as reasonably soon as possible.)
How Do You Get A-Fib? What causes, OR Triggers A-Fib?
For many A-Fib patients (around 50%), there is no discernible cause or trigger for their A-Fib (called Lone A-Fib).
For the others, the following may contribute to their Atrial Fibrillation:
If you’ve had other heart problems, this could lead to diseased heart tissue which generates the extra A-Fib pulses—possibly because they stretch and put pressure on the pulmonary veins where most A-Fib originates. Up to 40% of patients get A-Fib after open heart surgery.
Heavy drinking may trigger A-Fib. Extreme fatigue, emotional stress, severe infections, severe pain, traumatic injury, and illegal drug use can trigger A-Fib. Low or high blood and tissue concentrations of minerals (electrolytes) such as potassium, magnesium and calcium can trigger A-Fib. Thyroid problems (hypothyroidism), lung disease, reactive hypoglycemia, viral infections, kidney disease, diabetes, and smoking can trigger A-Fib.
As we put on pounds, our risk of developing A-Fib increases.
A-Fib can run in families.
Some cases have been reported where antihistamines, bronchial inhalants, local anesthetics, medications such as sumatriptan, a headache drug. Tobacco use, MSG, cold beverages, coffee, chocolate, high altitude, GERD, sleep apnea and even sleeping on one’s left side or stomach are said to have triggered A-Fib.
A-Fib is associated with aging of the heart. As patients get older, the prevalence of A-Fib increases, roughly doubling with each decade. This suggests that A-Fib may be related to degenerative, age-related changes in the heart.
For a more in-depth discussion of A-Fib causes and triggers, see Causes of A-Fib.
Review of Treatments
The key to stopping A-Fib is to eliminate the extra electrical pulses A-Fib generates.
Doctors usually start with medications (called drug therapy) to try and control the rhythm and rate of the heart. For most A-Fib patients drugs aren’t very effective (about 40-50% success rate) or have serious side effects. For a more in-depth discussion, see Treatment/Drug Therapies.
Sometimes an electrical shock called a cardioversion is used to return your heartbeat to normal. The benefit is usually temporary. For most A-Fib patients, their A-Fib returns in a week to a month (see Treatments/Cardioversion).
Drug therapy and cardioversion have their roles, but they ‘manage’ your A-Fib. Neither treatment eliminates or ‘cures’ your A-Fib.
But know that Atrial Fibrillation is curable.
An effective treatment to eliminate these extra electrical pulses is Pulmonary Vein Ablation (PVA), a type of catheter ablation. 75,000 to 100,000 A-Fib ablations are performed in the U.S. every year, and this number is rapidly growing.
A soft, flexible tube (a catheter) with an electrode at the tip is inserted into a vein in your groin and moved to the inside of your heart.

Catheter inserted into the heart and through septum wall into Left Atria
The catheter is directed to the precise locations in your heart that produce these extra signals. Using radiofrequency (RF) or other energy sources, these areas are burned off or “isolated”― disrupting the path of the irregular signals.
You are usually under general anesthesia during the PVA which means you don’t feel anything. If you are under “conscious sedation” and are awake during the procedure, you won’t feel the catheter being moved through your veins. There are usually no nerve endings in blood vessels. You also won’t feel a lot of the burns in your heart. There are motor nerve endings but usually no sensory nerve endings in the heart. But the procedure isn’t painless. Most patients can go home the next day. See Treatments/Catheter Ablation.
Surgery can also be an effective option to eliminate or isolate A-Fib pulses. The open-heart version is the Cox Maze, but it’s usually only performed concurrently with other heart surgery, such as Mitral Valve replacement.
The more frequently performed surgery is the Mini-Maze which accesses the heart through several small incisions in the chest or diaphragm. The catheters and a tiny camera are inserted to locate, then burn or “isolate” the extra signals. All from outside of the heart. A stay in the hospital is necessary to recuperate. See Treatments/Cox Maze and Mini-Maze operations.

Typical Mini-Maze incisions for surgical ablation of Atrial Fibrillation
For a more thorough discussion of the various treatments for A-Fib, see Treatments.
The Wrap-up
The bottom line is—how do you feel? If you don’t feel any symptoms and your doctor says your heart isn’t enlarging and/or developing poor ejection fraction, etc., then there’s no urgent need to rush out to get a Pulmonary Vein Ablation (or surgery).
Some people decide to simply live with A-Fib (usually while on A-Fib medications) rather than to undergo treatments to make them A-Fib free. (I am personally biased against just living with A-Fib. When I had A-Fib, it drove me nuts!) But realize that A-Fib is a progressive disease that usually harms your heart over time.
On the other hand, if you have bothersome A-Fib symptoms, if it’s impacting your quality of life, if you are miserable, then pursue treatment options that go beyond drug therapy, i.e., a Pulmonary Vein Ablation.
Your next step is to find the best doctor you can afford, who specializes in treating irregular heartbeats (i.e. an electrophysiologist, a type of Cardiologist). For advice in selecting the right doctor, see Finding The Right Doctor.
Additional Readings
• Causes of A-Fib
• Find the Right Doctor for You
• Treatments for A-Fib
• FAQs: Coping with A-Fib
• Personal A-Fib Stories of Hope
• Resources & Links
Remember: You don’t have to “just take your meds and get used to it.” (A quote from one patient’s doctor.) You don’t have to settle for a life on meds. Seek your Cure!
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If you find any errors on this page, email us. Y Last updated: Sunday, June 19, 2022
•McCarthy, P. et aL Surgery and Catheter Ablation for Atrial Fibrillation: History, Current Practice, and Future Directions. Journal of Clinical Medicine, December 31, 2021.