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Atrial fibrillation (also called AF or A-Fib) is the most common type of irregular heartbeat, occurring in 1-2% of the general population. However, it is a problem that increases with age, with approximately 5-15% of people between 80-90 years of age affected. There is also an increased risk of atrial fibrillation among people with heart conditions, including irritation of the membrane surrounding the heart (pericarditis), heart muscle disease (cardiomyopathy), abnormal heart valves or congenital heart defects.

Atrial fibrillation occurs when electrical signals in the heart’s upper chambers (atrium) cause the atrium to beat quickly and erratically, causing an irregular fast heart rhythm. As a result, the heart may not be able to pump enough blood around the body or out of the atrium completely with each heartbeat. If not correctly treated, atrial fibrillation can lead to heart failure. People with atrial fibrillation also have a 5 times higher risk of a potentially fatal stroke as the condition can cause blood clotting that blocks the artery supplying blood to the brain.

Heart diseases including heart attack from blockage of heart vessels (coronary artery disease or acute myocardial infarction), abnormal heart valves, heart muscle disease (cardiomyopathy and myocarditis), high blood pressure (hypertension), and irritation of the membrane surrounding the heart (pericarditis)
Other conditions, including over function of thyroid gland (hyperthyroidism) and lung diseases such as emphysema, sepsis, postoperative complications, cerebral haemorrhage and stroke
Unknown causes

First diagnosed atrial fibrillation: When the atrial fibrillation is first identified, it is classified as first diagnosed atrial fibrillation. If it is restricted to only one episode, it is called acute atrial fibrillation, which is a common arrhythmic problem after heart surgery. If it occurs more than once, it is classified as paroxysmal atrial fibrillation and requires treatment.
Paroxysmal atrial fibrillation: In this case, the atrial fibrillation begins suddenly and then stops on its own. In most cases of paroxysmal AF, the episodes will stop within 24 hours, although they can last up to 7 days.
Persistent atrial fibrillation: When the atrial fibrillation lasts for more than 7 days or cannot stop on its own, it is classed as persistent AF.
Long standing persistent atrial fibrillation: If the atrial fibrillation lasts for more than 1 year, and the doctor and patient decide to treat the condition and return the heartbeat to normal, it is classed as long standing AF.
Permanent atrial fibrillation: If the atrial fibrillation lasts for more than 1 year, and the doctor and patient decide not to treat the condition, it is permanent AF.

More than half of patients with atrial fibrillation have no visible symptoms (asymptomatic). The condition is usually detected when a patient sees the doctor about a related complication, particularly paralysis of one part of the body. Those who do have symptoms may experience the following:

Palpitations, irregular heartbeat
Shortness of breath, weakness
Becoming tired easily during exercise
Decrease in ability to exercise
Chest pain
Lightheadedness
Difficulty breathing
Fainting

Check of heart rate and rhythm
Electrocardiogram
Other laboratory tests, including:
- Anemia or kidney function test
- Thyroid function test
- Chest x-ray
- Echocardiography

The goals of atrial fibrillation treatment include reducing the symptoms and complications, with the aim of minimizing mortality rates and hospitalization. The type of treatment depends on the age of the patient, medical history, symptoms, other medical conditions, and type of atrial fibrillation.Treatment options include the following:

Medications can be administered to:
- slow the heart rate (rate control)
- control the rhythm (rhythm control)
- reduce the risk of blood clots that form and cause blockage of vessel supply to any part of the body but especially the brain
Electrical cardioversion is used to restore a normal rhythm to the heart immediately and is only used in urgent conditions. This procedure cannot prevent a recurrence of atrial fibrillation. A regular rhythm has to be maintained through either long-term medication or ablation.
Radiofrequency ablation or cryoablation is used to eliminate the abnormal signals that cause atrial fibrillation. This procedure restores the normal heart rhythm immediately and prevents any recurrence of atrial fibrillation in the future.