The Early Show medical correspondent Dr. Emily Senay explains that it occurs when electrical impulses cause the upper heart chambers to quiver instead of beating normally, and blood isn't completely pumped out of the heart. That can cause weakness, palpitations and rapid heartbeat. One of the big dangers is that excess blood can collect and form clots, increasing the risk of clots and stroke.
The American Heart Association estimates that 2.2 million Americans have atrial fibrillation, and about 15 percent to 20 percent of strokes occur in people who have it.
The risk of developing atrial fibrillation increases with age, and the standard drug treatments and electric shock therapy don't always keep the condition from returning.
But a new procedure is promising.
It uses heat generated by radio wave energy similar to that from a microwave. A catheter is fed into the heart, and heat is delivered to block the cells in and around the heart that are the source of the disruptive electrical impulses that cause the irregular heartbeat.
It's a technique that has been shown to work, and it's approved for people who experience this type of irregular heartbeat only occasionally, when the standard drug treatments don't work.
But many people with atrial fibrillation have the chronic form, which they have to endure for years when the standard treatments fail.
And a study in this morning's New England Journal of Medicine tested a new form of the radio wave heat therapy on people with the chronic irregular heartbeat, and found that the treatment eliminated it in 74 percent of patients for one year.
The new form maps out which cells are causing the problem and zeroes in on them, Senay told co-anchor Hannah Storm Thursday.
Some patients required a second round of heat treatment to complete the job.
The research showed that the procedure had all-around positive effects on heart rhythm, symptoms, quality of life and heart function.
There are some patients with additional heart problems and older patients who may not be candidates for the procedure, Senay points out. Further study is needed to see which patients will benefit most.
The treatment isn't recommended as a first line treatment for atrial fibrillation, and it's not widely available at every hospital. But the hope is that many more people who suffered, with no other options, from the persistent form can be helped.
If you have atrial fibrillation, ask your doctor about whether you are a candidate for the procedure.