Heart Surgeon Develops Procedure To Treat Atrial Fibrillation

Main Category: Cardiovascular / Cardiology
Article Date: 20 Jun 2007 - 7:00 PDT

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A heart surgeon at FirstHealth Moore Regional Hospital has pioneered the development of a procedure that corrects atrial fibrillation, an often debilitating heart disorder that affects an estimated five million Americans.

Andy C. Kiser, M.D., has performed the procedure on about a dozen patients in Pinehurst and assisted on several other patients in Germany, Poland and Sacramento, Calif.

Dr. Kiser's work has attracted national and international attention. He presented scientific papers at the American Heart Association Scientific Session in Boston in November and at the NewEra Cardiac Surgery Forum in Huntington Beach, Calif., in January. Earlier this month, he was in Rome to present additional research to the International Society of Minimally Invasive Cardiac Surgery.

Atrial fibrillation, the most common heart rhythm disorder, is the erratic, uncoordinated beating of the atria, the two small, upper chambers of the heart. The atria are supposed to beat rhythmically to pump blood into the ventricles, the lower chambers. But in atrial fibrillation, the electrical impulses that trigger atrial contractions don't follow the normal pathways and instead travel through the heart in a chaotic fashion.

This chaotic movement causes the atria to quiver instead of beating normally. Blood collects in the atria and moves through the heart sluggishly and intermittently, and blood pressure drops. Common symptoms include weakness, lightheadedness, shortness of breath and chest pain.

About 15 percent of strokes are the result of atrial fibrillation, which in severe cases can also cause heart failure.

A clinical assistant professor of surgery at the Brody School of Medicine at East Carolina University in Greenville, Dr. Kiser has been working in association with other surgeons to develop a way to burn the muscles of the heart and create a pattern of scar tissue that prevents the electrical currents from straying off course.

Treating atrial fibrillation by scarring the heart isn't new. Surgeons have used dozens of methods and various "maze" patterns. But the pattern Dr. Kiser designed and the device he uses allow him to burn the heart muscle and create scar tissue while the heart is beating.

"Other surgeons who do the maze procedure either do half of a maze or stop the heart to do it," Dr. Kiser says. "If the heart isn't beating, it isn't conducting electricity, so you can't tell whether the procedure works or not. With the heart beating, I can see the atrial fibrillation correct to a normal heart rhythm during the procedure, ensuring the procedure was successful."

The pattern of scar tissue that Dr. Kiser creates on the heart is called the "Ex-Maze Procedure." Last summer, he led a meeting of surgeons in Germany during which they agreed upon the design of the Ex-Maze and began its evaluation in Poland and at four German hospitals.

"They are continuing to evaluate this procedure, and the results have been impressive," Dr. Kiser says. "The safety and the success of the procedure have allowed me to confidently treat patients in the U.S.."

The new procedure was effective in stopping atrial fibrillation in 35 of the first 41 patients who were treated in Europe.

The device Dr. Kiser uses was developed by nContact Surgical Inc., of Morrisville, N.C., and has been approved by the Federal Food and Drug Administration for use on the heart. A vacuum system that keeps the device in constant contact with the heart helps ensure that the pattern of scar tissue is consistent and unbroken.

"This device allows us to treat an entire segment of the population who have chronic atrial fibrillation and aren't getting any effective treatment," Dr. Kiser says.

Dr. John F. Krahnert, chief of Cardiac Surgery at FirstHealth Moore Regional, agrees. "Dr. Kiser has utilized this new technology to leverage decades of medical research regarding atrial fibrillation," he says.

The Ex-Maze pattern that is created on the outside of a beating heart reproduces the patient outcome benefits associated with the "gold standard" treatment for atrial fibrillation, the "cut-and-sew" Cox Maze III procedure. New studies may indicate that the Ex-Maze is as effective as the Cox Maze, but without its complexity.

"The power of the new procedure is in taking new technology and combining years of atrial fibrillation research to create a new procedure for patients who have had no good treatment alternatives," Dr. Krahnert says.

Atrial fibrillation can be caused by anything that damages the heart muscle, including hypertension, infections, hyperthyroidism, and various heart and lung diseases. Atrial fibrillation is most common in older adults, and it is estimated that up to 5 percent of people over 65 have it.

Medications are often effective in treating people who have occasional atrial fibrillation. But five times as many people have chronic atrial fibrillation, and the methods used to treat them so far - including variations of the maze procedure - have had limited success, Dr. Kiser says.

"These technologies have not provided a comprehensive solution to atrial fibrillation," he says. "And the number of people treated with these technologies represents less than 1 percent of the total population of atrial fibrillation patients."

So far, in the United States, the Ex-Maze procedure has been performed only on patients whose chests had been opened for some other heart procedure such as a coronary artery bypass or valve repair. But Dr. Kiser soon expects to make the procedure available to patients who have severe atrial fibrillation but no other heart problems for which heart surgery is needed.

The new procedure can be done in about one hour, and patients will typically spend two to four nights in the hospital before going home.

Dr. Kiser is a member of Pinehurst Surgical, a large, multi-subspecialty surgical practice in Pinehurst. The chief of Thoracic Surgery at Moore Regional Hospital and medical director of the Chest Center of the Carolinas, he has been performing heart and lung surgery at Moore Regional since 2000.

While in Europe earlier this month, Dr. Kiser performed the world's first Ex-Maze procedure without opening the patient's chest. The minimally invasive procedure, which took place in Krakow, Poland, required just four small laparoscopic incisions and took about two hours to perform.

"This was a tremendous success," Dr. Kiser says. "The minimally invasive Ex-Maze procedure is truly a revolutionary opportunity for all patients with atrial fibrillation."

For more information on the atrial fibrillation procedure developed by Dr. Andy Kiser, www.firsthealth.org. Additional information is also available on the Ex-Maze Web site at www.exmaze.com.