by Wood D


Atrial fibrillation (AFib) is an erratic and often fast beating of the upper part of the heart. This part of the heart pushes blood into the lower section of the heart so it can pump blood out to the body. AFib can decrease the amount of blood that is pumped out to the body. AFib may be:

  • Occasional (paroxysmal)—AFib starts and stops over short periods usually less than 48 hours
  • Persistent—constant and lasts more than 7 days
  • Longstanding persistent—continues for more than a year
  • Permanent
Atrial Fibrillation
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The beating of the heart is started and controlled by electrical signals. These signals start from an area of the heart called the SA node. The signals then move through the heart in an organized way. Problems with the SA node or other areas of the heart can disrupt how the heart contracts. Irregular signals may also start in other areas of the heart.

Afib may be caused by one or more of the following:

  • Problem with how the heart developed or damage to the heart
  • Metabolic disorders—how your body processes food
  • Endocrine disorders—abnormal amounts of hormone in your body
  • Certain medicine or other medical treatment

Sometimes the exact cause is not known.

Risk Factors

AFib is more common in men and people over 55 years old.

AFib may also be more likely in those with:

Certain habits and food or drinks can increase the risk of AFib:

  • Smoking
  • Excessive alcohol use
  • Excessive use of stimulants like caffeine
  • Physical and/or emotional stress


AFib may not cause any symptoms. Symptoms that do occur may range from mild to severe.

Fast beating in the upper part of the heart may cause:

  • Irregular or rapid pulse or heart beat
  • Racing feeling in the chest
  • A pounding feeling in the chest

AFib that is decreasing the amount of blood pumped out to the body may cause:

  • Lightheadedness, which can lead to fainting
  • Sweating
  • Pain or pressure in the chest
  • Shortness of breath
  • Fatigue or weakness
  • Hard time exercising


The doctor will ask about your symptoms and past health. A physical exam will be done. The doctor may suspect a problem after listening to the heart or hearing about symptoms. Tests to confirm may include:

  • ECG —shows the electrical patterns of the heart.
  • Holter monitor —ECG that is worn over a 24 to 48 hours period while you have a normal day. It can help show problems that do not occur all the time.
  • Stress testing—ECG during exercise to see changes that only happen with physical activity.


For some people, AFib will go away without treatment. For others, goals of treatment may include:

  • Stopping AFib (when possible).
  • Slowing the fibrillation down; especially if you are having symptoms.
  • Decreasing the risk of other problems such as blood clots and stroke. Very important in AFib that keeps coming back or is permanent.

The exact plan will depend on the cause of your AFib. If a cause is found, that may need to be managed first. For example, stopping or changing medicine may stop the AFib.

Heart Rhythm Control

Steps that may help slow or stop AFib include:

  • Medicine—to slow the heart rate or keep the heart in a regular rhythm
  • Cardioversion—uses an electrical current or drugs to get a normal heart rhythm
  • Surgical procedures—to redirect or slow the electrical signals of the heart
    • Ablation—an area of the heart may be damaged or scarred to stop stray electrical signals
    • Maze procedure and mini-maze procedure —a pattern of scar tissue is created to block fast or irregular electrical signals

Clot and Stroke Prevention

AFib allows blood to pool in the upper part of the heart. Blood clots can form in this pool, travel out of the heart, and cause a stroke. Medicine will help to stop these clots from forming. Some medicine can also increase the risk of severe bleeding. Care team will track changes in the blood to keep a balance between preventing blood clots and bleeding risks.

A procedure called left atrial appendage closure (LAAC) may be considered if medicine is not an option. This procedure seals off a small area of the upper heart where clots tend to form.

Reducing Triggers

Certain habits can trigger an episode of AFib or make it worse. To decrease the chance of making the AFib worse:

  • Stop smoking
  • Reduce or eliminate caffeine
  • Reduce stress
  • Eliminate or reduce alcohol intake


It is not always possible to prevent AFib. Talk to your doctor about your overall heart health. A healthy heart may reduce the risk of some AFib.


American Heart Association 

Heart Rhythm Society 


Canadian Heart Rhythm Society 

Heart and Stroke Foundation of Canada 


Atrial fibrillation. EBSCO DynaMed website. Available at: Accessed November 28, 2020.

Atrial fibrillation. CardioSmart website. Available at: Accessed November 28, 2020.

Electrical cardioversion. Cleveland Clinic website. Available at: Accessed November 28, 2020.

Explore atrial fibrillation. National Heart,Lung, and Blood Institute website. Available at: Accessed November 28, 2020.

Left atrial appendage and closure. Cleveland Clinic website. Available at: Accessed November 28, 2020.

1/2/2014 DynaMed Plus Systematic Literature Surveillance Abed HS, Wittert GA, Leong DP, et al. Effect of weight reduction and cardiometabolic risk factor management on symptom burden and severity in patients with atrial fibrillation: A randomized clinical trial. JAMA. 2013;310(19):2050-2060.

7/1/2015 DynaMed Plus Systematic Literature Surveillance Qureshi WT, O'Neal WT, Khodneva Y, et al. Association between opioid use and atrial fibrillation: The Reasons for Geographic and Racial Differences in Stroke (REGARDS) study. JAMA Intern Med. 2015;175(6):1058-1060.

4/5/2018 DynaMed Plus Systematic Literature Surveillance  : Asad Z, Abbas M, et al. Obesity is associated with incident atrial fibrillation independent of gender: a meta-analysis. J Cardiovasc Electrophysiol. 2018 Feb 14.

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