What is Atrial Fibrillation?

Atrial fibrillation is a type of heart disease that can lead to heart failure or stroke, and it is increasingly common. Educate yourself by learning about the causes and possible complications of atrial fibrillation

Since my own mother has this troublesome health condition, I thought I'd post this educational piece on Atrial Fibrillation, taken from today's health websites:


by Chris Iliades, medically reviewed by Pat F. Bass III, MD, MPH

Atrial fibrillation is a common form of heart disease and the most common cause of irregular heart rhythms that start in the upper chambers of the heart, called the atria. The term fibrillation refers to a fluttering, disorganized type of heartbeat — heart flutter.

"Atrial fibrillation tops the list of abnormalities that can occur in the heart's normal rhythm," says Douglas C. Westveer, MD, chief of cardiovascular disease at Beaumont Hospital in Troy, Mich.

According to the American Heart Association, about 2.2 million Americans have this form of heart disease. "Even more alarming, the incidence of atrial fibrillation is increasing and may reach epidemic proportions as more baby boomers enter older age groups," notes Dr. Westveer.

What Happens During Atrial Fibrillation?
A normal heart rhythm depends on a special sequence operating correctly. The two upper chambers of the heart are where a normal heartbeat begins. The electrical impulse for the beat starts in an area of the right atrium called the sinoatrial (SA) node. After the atria contract, the impulse goes to another node called the atrioventricular (AV) node. This node is located near the middle of the heart, and it triggers the lower chambers of the heart to contract, which pumps blood to the lungs and the body. When your heart is functioning normally, it beats about 60 to 100 times per minute.

But with atrial fibrillation, the SA node is not controlling the beginning of the hearbeat in the atria. "The atria are composed of millions of individual muscle cells that all contract together to create a normal heartbeat. During atrial fibrillation, each muscle cell contracts independently, resulting in the quivering action referred to as fibrillation," explains Westveer.

As the AV node gets overwhelmed with chaotic impulses from all over the atria, many impulses pass through, resulting in a rapid and irregular heartbeat that can get up to over 300 beats per minute.

Atrial Fibrillation Symptoms
There are two types of atrial fibrillation. "Some patients have 'paroxysmal' atrial fibrillation, a relapsing form of arrhythmia that often lasts for hours and may recur frequently over time. Others have a chronic type that continues for the remainder of their lives," says Westveer.

Symptoms of atrial fibrillation may include:

The sensation of heart flutter known as palpitations
Shortness of breath
Fatigue
Dizziness
Chest pain

Causes and Risk Factors for Atrial Fibrillation
Atrial fibrillation is associated with many different conditions including:

Heart disease
High blood pressure
Chronic lung disease
Overactive thyroid gland

A blood clot that lodges in the lungs In about 10 percent of people with atrial fibrillation, an underlying cause is never identified.

The biggest risk factors for atrial fibrillation are age and underlying heart disease, such as coronary artery disease or heart valve disease. Risk increases after age 60. By age 65, about 4 percent of people will have atrial fibrillation. Other risk factors include smoking, excessive caffeine, and stress.

Complications of Atrial Fibrillation
The two big complications from atrial fibrillation are blood clots and heart failure. Blood clots occur because blood that is not moving normally tends to clot. "Blood clots may form inside the atria over time and are a leading cause of stroke," says Westveer. A stroke can occur when a blood clot leaves the heart and gets lodged in an artery inside the brain. About 15 percent of all strokes happen in people with atrial fibrillation.

Heart failure occurs because the heart is not beating effectively and gradually gets weaker and weaker. Heart failure symptoms such as fatigue, shortness of breath, and fluid retention can develop over time as atrial fibrillation makes the heart work harder and grow weaker.

Fortunately there are many options to help prevent stroke and heart failure symptoms. "Although the prevalence of atrial fibrillation continues to increase, new treatment strategies are opening a brighter outlook for its management. The treatment choices should be fully discussed with your doctor," says Westveer.

Atrial fibrillation is more than just a heart flutter; it may be a sign of heart disease and it may put you at risk for stroke and heart failure. Talk to your doctor if you think you may have symptoms of atrial fibrillation.