Atrial Fibrillation

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 Graphic of Vibrating Heart

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." You may feel lightheaded (fainting), very tired, have shortness of breath, sweating and chest pain, and sometimes a distressing need for frequent urination (probably because of the release of atrial natriuretic peptide [ANP])²¹¹.
Somewhere in your heart extra electrical signals are being generated which cause the top part of your heart to contract and quiver rapidly and irregularly (fibrillate) as many as 300-600 times a minute.
Normal and A-Fib EKG

If you'd like an explanation of the various parts of the EKG signal, go to The EKG Signal. To watch an excellent, though technically challenging, animation of A-Fib and other heart rhythm problems, go to http://www.blaufuss.org/SVT/index2.html. (Thanks to Tom Burt for calling our attention to this site.)
Your whole heart, however, does not beat that fast. Your heart is a muscular pump divided into four chambers---two atria located on the top and two ventricles on the bottom. Normally each heart beat starts in the right atrium where a specialized group of cells called the Sinus Node generates an electrical signal that travels down a single electrical road (the AV Node or AV Junction) that connects the atria to the ventricles below. This electrical signal causes the heart to beat. First, the atria co

ntract, 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 60-80 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 on their own sometimes as rapidly as 600 times a minute. 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 heart beat 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.
ATRIAL FLUTTER
Some people have Atrial Flutter along with their A-Fib, or sometimes by itself without A-Fib. In Atrial Flutter the atria don't fibrillate but rather beat faster than the ventricles but in a coordinated, regular rhythm. You can consider Atrial Flutter as a more regular, milder variety of A-Fib. A-Flutter often, though not always, originates in the right atrium, whereas A-Fib usually comes from the left atrium. Here is an EKG of Atrial Flutter:

HOW SERIOUS AN ILLNESS IS A-FIB?

Stroke risk
    If you have A-Fib, 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. Graphic of Heart and EKG 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.¹⁰⁶ Researchers estimate that 35% of patients with A-Fib will suffer a stroke¹⁰⁷ (unless treated).
    The American Heart Association states that A-Fib is a major cause of stroke, especially if you're older. It estimates that 15% of strokes come from untreated A-Fib. An A-Fib stroke is worse than other causes of stroke. Half of all strokes associated with atrial fibrillation are major and disabling.¹⁶⁸ 23% of A-Fib stroke patients die, and 44% suffer significant neurologic damage. This compares to only an 8% mortality rate from other causes of stroke.^132,
166
    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.⁷² Silent A-Fib is very common. Up to 30% of A-Fib patients are unaware they have A-Fib.¹⁴⁰25% of those who suffered an A-Fib stroke had no prior diagnosis of A-Fib.^141,142

Talk to your doctor about blood thinners
    If you have A-Fib, it is most important to talk to your doctor about taking a blood thinner like aspirin (Plavix, Ticlid) or warfarin (Coumadin) to help prevent these clots from forming. (Plavix and Ticlid are antiplatelet drugs like aspirin but they are not the same or interchangeable with aspirin. If your doctor prescribes Plavix or Ticlid, you should not substitute aspirin for them.)
    However, especially 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 a blood thinner. (For a more detailed discussion of anticoagulation for patients with A-Fib, go to Dr. Waldo's presentation 2006 ACC/AHA/ESC Guidelines for the Treatment of A-Fib - Update and Critique: Impact of A-Fib Guidelines on Clinical Practice.)
    (There are two main types of stroke. A clot in a narrow blood vessel is called an "ischemic" stroke and is the kind that often occurs in A-Fib. Almost 85% of strokes are ischemic. A "hemorrhagic" stroke occurs when a blood vessel leaks blood into the brain.)⁵⁶
    See also the FAQs questions # 40 "Should anyone who has A-Fib be on the blood thinner warfarin (Coumadin)?" and #41 "Which is the better anticoagulant to prevent stroke---warfarin (Coumadin) or aspirin?"

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 the rest of your body by about 15%-30%.^164,
165 You may not be getting enough blood to your brain and other organs which may cause weakness, fatigue, dizziness, fainting spells, and shortness of breath.
    Recent studies indicate that A-Fib reduces mental abilities and may lead to dementia.⁹⁸ Patients with A-Fib are 44% more likely to develop dementia.¹⁶³ (See A-Fib Patients at Risk of Dementia and Ablation of A-Fib Reduces Risk of Alzheimer's and Dementia.) Permanent (Chronic) A-Fib has been found to significantly reduce blood flow to the brain and brain function.⁷⁶
    A-Fib untreated can also lead to more serious heart rhythm problems and to heart failure⁷⁷. 20-50% of patients suffering from A-Fib develop heart failure.²¹⁰ Inefficient atrial pumping puts an added burden on the ventricles. Prolonged A-Fib episodes may stretch and weaken the heart muscle.¹⁶⁴ The ability of the atria to contract is diminished (called "ejection fraction"). "A-Fib with a persistent rapid rate can cause a form of heart failure called tachycardia induced Cardiomyopathy, which can significantly increase mortality and morbidity."¹⁶¹ If you have A-Fib, you're more likely to die than someone in normal heart rhythm. A-Fib nearly doubles your chances of death.⁶¹
    But please weigh the above statements carefully (the author is concerned that they may create unwarranted fear). 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 need to rush out to get a Pulmonary Vein Ablation which does involve low but nevertheless real risk.

A-Fib remodels your heart and is a progressive disease
Graphic of Clock and EKG     It's important to be treated as reasonably soon as possible. A-Fib begets A-Fib. 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 a study of 5,000+ A-Fib patients, 54% of those on rate control meds went into permanent A-Fib in one year.¹⁶⁴However, 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 [see Left Atrial Function...After Catheter Ablation].
     If you have occasional episodes of A-Fib and don't have other serious heart problems, you most likely have Focal A-Fib and stand a good chance of being cured by Pulmonary Vein Ablation. 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 (CAUSES)? Man Scratching Head

Nearly three million people in the U.S. have A-Fib. By the year 2050, the number will be 5.6 million.⁷¹ This year there will be over 340,000 new cases in the US. A-Fib is the most common heart arrhythmia.¹⁴⁶ In the U.S. people over 40 have a one in four lifetime risk of developing A-Fib.⁸²
If you've had other heart problems, this could lead to diseased heart tissue which generates the extra A-Fib pulses. Hypertension (high blood pressure), Mitral Valve disease, Congestive Heart Failure, and obesity¹³² seem to be related to A-Fib, possibly because they stretch and put pressure on the pulmonary veins where most A-Fib originates. Many people ("up to 40% of patients"⁴²) get A-Fib after open heart Champagne Bottle and Glasses

surgery. "Pericarditis"---inflammation of the pericardium, a sack-like membrane surrounding the heart---can lead to A-Fib.

    Heavy drinking may trigger A-Fib, what hospitals call "holiday heart"---the majority of A-Fib admissions occur over weekends or holidays when more alcohol is consumed.
    Extreme fatigue, emotional stress, severe infections, severe pain, and illegal drug use can trigger A-Fib. Low or high blood and tissue concentrations of minerals such as potassium, magnesium and calcium can trigger A-Fib. Thyroid problems (hyperthyroidism), lung disease, reactive hypoglycemia, viral infections, and smoking can trigger A-Fib. Smoking cigarettes raises the risk of developing A-Fib even if one stops smoking, possibly because past smoking leaves behind permanent fibrotic damage to the atrium which makes later A-Fib more likely.¹²⁹
    DNA

Some research has identified a Familial A-Fib where A-Fib is passed on genetically²⁸ but it is relatively rare. (Author's theory: Some consider all A-Fib genetic in that we are born with A-Fib triggers---usually the Pulmonary Vein Openings in the Left Atrium. They seem to be genetically related to and similar in structure to the AV Node, the natural pacemaker of the heart. They usually beat in sync with the AV Node. But when impaired, they start beating on their own producing A-Fib signals. Be advised that this is only a theory and not established medical fact.)
    Some cases have been reported where antihistamines, bronchial inhalants, local anesthetics, medications such as sumatriptan, a headache drug,¹³² tobacco use, MSG, cold beverages, high altitude, and even sleeping on one's left side or stomach are said to have triggered A-Fib. The author used to include caffeine (coffee, tea, sodas, etc.) in this list, but some research suggests that coffee and caffeine in moderate to heavy doses (2-3 cups to 10 cups/day) may not trigger or induce A-Fib.^144,
145 Coffee (caffeine) may indeed be antiarrhythmic and may reduce propensity and inducibility of A-Fib both in normal hearts and in those with focal forms of A-Fib.¹⁴³(Thanks to Karl for calling our attention to these articles.)Chocolate in large amounts may trigger attacks. Chocolate contains a little caffeine, but also contains the structurally related theobromine, a milder cardiac stimulant (thanks to Prof. Phil Page from the UK for this info). GERD (heartburn) and other stomach problems (like H. pylori) may be related to or trigger A-Fib. If so, antacids and proton pump inhibitors like Nexium may help your A-Fib (Thanks to Ian Betts for this observation). A report from England suggests that the veterinary antibiotic "Lasalocid" found in eggs and poultry meat may cause or trigger A-Fib.⁶⁵ One person writes that hair regrowth products seem to trigger his A-Fib. Another writes that the natural sweetener and sugar substitute Stevia seems to trigger her A-Fib.

SLEEP APNEA
    Recent research indicates sleep apnea (where your breathing stops while you are sleeping) may contribute to A-Fib, probably by causing stress to the Pulmonary Vein openings.⁹⁰ Many people have sleep apnea and don't know it. Your significant other can tell you if you snore a lot, which is often a sign of sleep apnea. If you have A-Fib, it might be wise to have yourself checked for sleep apnea. (Thanks to David Embler for this observation.)
    A Pulse Oximeter, available in drug stores, can give you a "quick" diagnosis of how much oxygen is in your blood. Below 90% would indicate you need to have a sleep lab study. (Thanks to Rose Vernier for this info.)
    (Gail writes that both her sleep apnea and her A-Fib were cured by a CPAP [Continuous Positive Airway Pressure] breathing machine. E-mail: gail(at)bonairwine.com [the "@" is written as "(at)" to avoid access by spam mailing lists].)

    If your A-Fib episodes occur usually at night, after a meal, when resting after exercising, or when you have digestive problems, you may have Vagal A-Fib. (See Vagal A-Fib)
    Athletes are more prone to A-Fib Graphic of Heart with Muscular Arms

perhaps because they have larger hearts where there is more room for these extra electrical signals to develop and propagate, and possibly because of the extra pressure they put on their pulmonary veins through aerobic exercise. A-Fib is often found in tall people, particularly basketball players.⁸⁹ Men get A-Fib more than women.
A-Fib is associated with aging of the heart. As patients get older, the prevalence of A-Fib increases, roughly doubling with each decade. 2-3% of people in their 60s, 5-6% of people in their 70s, and 8-10% of people in their 80s have A-Fib.^68,69,70 This suggests that A-Fib may be related to degenerative, age-related changes in the heart. Inflammation may contribute to the structural remodeling associated with A-Fib.⁸²
But in many A-Fib cases (around 50% of Paroxysmal A-Fib⁴⁴), there is no currently discernible cause or trigger (called "Lone" or "Idiopathic A-Fib").²⁶ (Some research suggests that inflammation may initiate Lone A-Fib.⁸⁴)

CURING A-FIB
The key to stopping A-Fib is to eliminate the extra electrical pulses A-Fib generates. Medications in general aren't very effective or have serious side effects. Sometimes an electrical shock can return your heart beat to normal. (For a more detailed discussion of cures for A-Fib, see CURES FOR ATRIAL FIBRILLATION)
A very effective treatment to eliminate these extra electrical pulses is Pulmonary Vein Ablation (Isolation). Under sedation anesthetic (you aren't knocked out) or general anesthesia a soft, flexible tube with an electrode at the tip is inserted into a vein or artery in your groin Doctor and Patient with Monitor

and moved into your heart. This catheter is directed to the precise location(s) in your heart that is producing these extra signals. Using radiofrequency (RF), laser, cryo or ultrasound energy these area(s) are burned off or isolated from your heart. All you feel is a little warmth or tingling. After the procedure you may feel a little tenderness or have some bruising in your groin where the catheter was inserted. Otherwise the procedure is usually painless, because there are no nerve endings inside the heart or blood vessels. See Cures for a discussion of the current methods of treating A-Fib.
A partial alphabetical list of medical facilities in the U.S. performing Pulmonary Vein Ablation (Isolation) is found under Facilities. See also Finding A Doctor.