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What is Atrial Fibrillation?

Atrial fibrillation, also known as A-Fib, is an irregular heart rhythm that affects the upper chambers of the heart (the atria). In A-Fib, the atria quiver instead of beating in a normal manner. A-Fib can also lead to rapid heart rhythm, where the heart can beat as much 300 times a minutes in the atria and up to 150 times a minutes in the lower chambers (the ventricles).

The importance of treating atrial fibrillation

At one time, A-Fib was believed to be harmless. As a result of the quivering rhythm in the atria during A-Fib, blood isn’t completely pumped out of the upper chambers of the heart, which may cause it to pool and clot. Atrial fibrillation increases the risk of a blood clot forming in the heart and becoming lodged in an artery in the brain, causing a stroke. While the condition isn't considered life-threatening, people with A-Fib are 5 to 7 times more likely to form blood clots and suffer a stroke.

Atrial fibrillation is also associated with chronic fatigue and heart failure – where the heart is unable to pump enough blood to the other organs. Fortunately, these risks can be reduced dramatically if they are monitored and treated. By working closely together, patients and doctors can choose the most appropriate course of care for the treatment of atrial fibrillation.

When does atrial fibrillation occur?

Atrial fibrillation can occur as a problem by itself – that is, unrelated to any other heart condition or disease. In such cases, it can be treated with medication or with catheter ablation by a cardiac electrophysiologist or with a surgical procedure by a cardiac surgeon.

A-Fib can also occur along with other types of cardiac conditions, for example, heart valve disease. Since A-Fib is associated with greater patient-care costs and greater risk of death, surgeons treat it when the patient undergoes mitral valve surgery. Treating atrial fibrillation in this manner has a positive impact on the patient's lifestyle and reduces the potential for stroke. It also reduces the patient's need for anti-arrhythmic and anti-coagulant medications as well as the side effects associated with them.

What are the symptoms of atrial fibrillation?

It is possible to have atrial fibrillation without feeling the symptoms generally associated with this condition. The usual symptoms of A-Fib include:

• Shortness of breath (for instance, when you climb stairs)
• Heart palpitations (uncomfortable sensation of a racing or irregular heartbeat)
• Chest pain
• Light-headedness, dizziness or even fainting
• Weakness

Types of A-Fib

There are 3 types of atrial fibrillation: paroxysmal (or intermittent), persistent, and permanent (or chronic).

1. Paroxysmal atrial fibrillation: brief episodes of abnormal heart rhythm that stop on their own. While these episodes are brief, they may still raise the risk of stroke and anticoagulant medication may be needed. Treatment of paroxysmal A-Fib can help patients who find its symptoms uncomfortable or disturbing.
2. Persistent atrial fibrillation: long periods of abnormal heart rhythm during which a normal rhythm can be restored with medication or electrical shock.
3. Permanent atrial fibrillation (also known as chronic atrial fibrillation): regular episodes of abnormal heart rhythm, where symptoms recur until they are treated.

Risk factors associated with A-Fib

In some people, atrial fibrillation may develop without obvious cause. However, a number of risk factors do exist that may make it more likely for a person to develop this condition. These risk factors include:

• High blood pressure
• Heart disease
• Heart valve disease
• Diabetes
• Overactive thyroid
• Lung disease

Age, as well, is a risk factor: the disease is more common in people who are over 60.

Lifestyle choices may also contribute to A-Fib, including excessive alcohol intake and the use of stimulants such as decongestants and coffee and drugs such as cocaine.

How is A-Fib diagnosed?

The same tests that are used to diagnose other arrhythmias are useful in determining if you have atrial fibrillation. See “How is an Arrhythmia Diagnosed?” for a description of these tests.

Treatment and its Objectives

There are two primary objectives in treating A-Fib.

1) To restore the heart’s normal rhythm
If A-Fib is left untreated, it may, over time, weaken the heart and lead to permanent damage. Restoring the heart’s regular rhythm can relieve the symptoms of A-Fib, considerably reducing the risk of dangerous blood clots developing.

2) To reduce the risk of stroke
Many patients with A-Fib use anticoagulant medication along with other treatments. This medication contributes to preventing clots, reducing the risk of stroke.

In some cases, another objective of treating A-Fib is to slow the heart rate and relieve symptoms without necessarily stopping the irregular heart rhythm. Slowing the heart rate allows the heart to pump oxygen-rich blood more efficiently, alleviating some or all the symptoms of A-Fib and helping to prevent the heart muscle from weakening. But it should be understood that slowing down and controlling rapid heart rates does not deal with the underlying arrhythmia. People with A-Fib should discuss the best course of action regarding treatment with their doctor.