Atrial fibrillation (sometimes referred to as AFib or AF) occurs when the upper chambers of the heart (the atria) beat fast and irregularly.

Because the upper chambers don’t contract or pump normally, the efficiency of the heart pumping function is lessened. This results in decreased blood flow to the rest of the body that can cause shortness of breath, heart palpitations, and general weakness.

Episodes of AFib can be sporadic or they may be present all the time. AFib isn’t typically life threatening, but it is associated with an increased risk of stroke, and if the heartbeat remains too fast for weeks or months, overall heart function can decrease.

AFib is treatable. Treatment options include:

• Medications to slow the heart rate during AFib
• Medications to stabilize the heart rhythm so normal heart rhythm is more likely
• Procedures, either using catheters inserted through the veins to the heart, or surgery -- to help restore and maintain a normal heart rhythm alone or in combination with medications

Learn more about atrial fibrillation treatment options

Causes

There is a wide range of conditions associated with AFib. The exact reasons that AFib develops in an individual are often difficult to identify.

Possible causes of AFib include a tendency for portions of the heart to beat very fast, generalized scarring of the upper heart chambers, heart disease such as narrowing or leaking of the heart valves, or decreased heart function due to previous heart attacks or inflammation of the heart muscle.

Medical problems that are associated with development of AFib include the following:

• High blood pressure
• Previous heart attacks
• Metabolic imbalance, such as overactive thyroid
• Exposure to stimulants or depressants, like caffeine or alcohol, or other drugs
• Lung disease, such as emphysema
• Viral infection, such as pneumonia
• Pericarditis, an inflamation of the tissue around the heart
• Sleep apnea
• Any disorder that increases the blood pressure within the heart chambers