A-fib is the most common clinical arrhythmia worldwide. It affects up to 3% of the Western population over the age of 20 years, according to estimates. A-fib is most prevalent in older adults, but it can occur at younger ages as well.

A person’s heart comprises four chambers: two upper chambers (the atria) and two lower chambers (the ventricles).

The heartbeat usually starts as a steady pulse in the right atrium. This results in a consistent, regular heartbeat and blood flow between the atria and the ventricles.

However, in people with A-fib, irregular electrical impulses cause the left and right upper chambers to twitch erratically and rapidly. This is called fibrillation. As a resultTrusted Source, the atria will beat unusually, thereby altering blood flow to the ventricles.

A-fib may not cause any symptoms, or the symptoms may only occur intermittently.

Often, the heart rate is higher than usual with A-fib. However, a person’s heart rate will depend on the frequency of the signals experienced by the atria and how rapidly they are conducted to the ventricle.

Some common symptoms include:

palpitations, or the feeling of an irregular heartbeat
breathlessness, particularly during exercise or activity
chest pain, pressure, or discomfort
low blood pressure
dizziness, lightheadedness, and fainting
fatigue
uneasiness

Causes

Certain factors increase the risk of developing A-fib. These include:

Age: The older a person is, the higher their risk of A-fib becomes.
Hypertension: Long-term high blood pressure can add strain to the heart and increase the risk of A-fib.
Pulmonary embolism: A blood clot in the lung may increaseTrusted Source the risk of a person developing A-fib.
Heart disease: People with underlying heart conditions have a higher risk of A-fib. These conditions include:
heart valve disease
heart failure
coronary artery disease
a previous heart attack
Excessive alcohol consumption: Heavy alcohol consumption can increase a person’s risk of developing A-fib.
Family members with A-fib: People with a family history of A-fib may be more likelyTrusted Source to experience the condition themselves.
Sleep apnea: People with this condition, especially when it is severe, have a higher risk of developing A-fib.
Other chronic conditions: Other long-term medical problems — including thyroid problems, asthma, diabetes, and obesity — may contribute to the risk of A-fib.

If a person does not experience any symptoms of A-fib, it may go untreated. A lack of treatment may lead to eventual complications, such as a stroke or heart failure.

A person with A-fib or suspected A-fib should pay attention to when their symptoms occur or change in severity. Recording these changes may assist doctors in providing a diagnosis and deciding on the best treatment.

The resulting arrhythmia may or may not produce symptoms. However, recognizing and treating A-fib early in its development can significantly improve the chance of preventing complications.

According to the American Stroke Association, a division of the American Heart Association, a global force for healthier lives for all.Most strokes caused by AFib could be prevented with effective treatment, but only about half of AFib patients receive proper therapy.

Approximately 5.2 million people in the United States experience AFib, and that number is expected to more than double in the next ten years, according to the American Heart Association.Although anyone can develop AFib at any age, the risk is greatest for individuals older than 50 years, those with a family history of AFib, smokers and those with high blood pressure or other forms of heart disease.

Although AFib is less prevalent in Black and Latino individuals compared with white individuals, Black and Latino people living with AFib have a higher risk of AFib-related death when they also have conditions such as high blood pressure and heart failure, according to the American Stroke Association.

The best-known symptom of AFib is a fluttering heartbeat, but not all individuals with AFib experience this, and many people with AFib report no symptoms prior to diagnosis."Because of this, it’s important that people at risk for AFib continuously speak to their doctors about any unusual sensations involving their heartbeat," says Mark Estes, medical expert and professor of Medicine and Program Director of the Clinical Cardiac Electrophysiology Fellowship at the University of Pittsburgh School of Medicine.

Other symptoms of AFib include shortness of breath, fatigue, dizziness, faintness, sweating and chest pressure.Up to 84% of strokes caused by AFib are preventable if patients receive early, effective treatment. That means it is important to talk to your doctor if you are at increased risk for AFib. The American Stroke Association offers a downloadable symptom tracker that can serve as an important tool for conversations with your doctor about how to stay healthy.