News Release

University Of Kentucky One Of First To Use New Technique To Treat Atrial Flutter

Peer-Reviewed Publication

University of Kentucky Medical Center

Last year, a minor earthquake erupted inside Johnnie Beavers' chest.

But yesterday, in a Kentucky medical first, physicians at the University of Kentucky Hospital used an experimental new technique called "microwave ablation" to calm the tremors in Beavers' heart, and give him back his breath.

During a non-surgical procedure lasting more than four hours, doctors directed microwave radiation -- the same kind of energy produced in home microwave ovens -- to "ablate," or make tiny burns, inside the upper chamber of the patient's heart.

The treatment was designed to block or destroy electrical pathways in the heart that were firing erratically and causing the upper chamber of the heart to quiver -- a condition called "atrial flutter."

Efforts to control it with conventional therapy had failed. But late yesterday UK officials termed the new treatment a success. They said that Beavers, 45, a music teacher, should be able to return to his Matewan, W.Va., home today.

It was the first time that microwave ablation -- approved by the FDA for study only in late August -- has been used outside California, where the first 10 or 12 procedures were performed. UK is one of five U.S. medical centers studying the technique.

UK's Dr. Andrea Natale, who treated Beavers and is a principal investigator on the study, says that, if early results hold up, microwave ablation could be an important alternative for patients whose atrial flutter defies traditional therapies.

Beavers just hopes it will give him his old life back. Until last year, he was a high school band director in West Virginia. But he had to quit after atrial flutter struck.

"I know now that I've had the problem for years, but it didn't get really bad until last year," he said shortly before the surgery. "I was so short of breath I almost didn't get through our homecoming parade. A few days later I went to the hospital, and they put me right in intensive care. It was pretty scary."

Atrial flutter is one of several different heart arrhythmias. By some estimates, it accounts for 5 percent of all emergency room visits. While not usually life-threatening in itself, flutter can limit work or other physical activities, and it may increase risk for stroke.

In some cases, atrial flutter can be treated with drugs. But last year, UK's Natale published a study showing that a form of ablation that used radio waves was more effective than medication. Now, he says the new ablation technique using microwaves may be even better.

In both techniques, a catheter is threaded through blood vessels from the groin into the heart.

In the older method, radio-frequency radiation was passed through the catheter, causing its tip to heat up. By touching the heated tip to appropriate areas in the heart, doctors could "turn off" any misfiring electrical circuits and stop the atrial flutter.

But in some patients -- particularly larger people with large hearts -- the heat failed to reach some deeply buried circuits, which allowed the atrial flutter to come back.

In the experimental method used yesterday, the catheter's tip contains an antenna that emits a small field of microwave energy. It is this energy that heats up the surrounding heart tissue -- even without touching it -- and shuts off the malfunctioning electrical pathways.

Natale, who heads UK's electrophysiology program and is an internationally recognized expert on ablation, says that using microwaves could make atrial flutter treatment a one-time proposition.

"Now, when we use radio waves to treat atrial flutter, the problem comes back in about 10 percent of the cases," he said. "But with microwaves, we might have to do it only once. It could make ablation much more effective."

Microwave ablation was developed by Fidus Medical Technology Corp. of Fremont, Calif. Teresa Mitchell, a senior vice president with the company, says that Massachusetts General Hospital, New York Hospital at Cornell University, the University of California at San Diego, and Sequoia Hospital in Redwood, Calif., are studying the technology along with UK.

Meanwhile, Johnnie Beavers hopes he's said goodbye forever to "feeling like my heart was flip-flopping around like it was going to jump out of my chest. I'm just looking forward to having a day when I can say I felt good all day long." The affliction

Microwave ablation is intended for patients who have atrial flutter, a condition in which the upper chambers of the heart tremble or flutter, instead of beating. It causes shortness of breath, and may pose an increased risk of stroke. Atrial flutter accounts for up to 5 percent of all emergency room visits. The condition also can be treated with drugs, or with another type of ablation that uses radio waves.

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