A cardiac surgeon at FirstHealth Moore Regional Hospital has developed a new treatment for atrial fibrillation—the most common type of heart rhythm disturbance—that is attracting international attention.
Andy Kiser, M.D., uses a unique method of burning the heart muscle, while the heart is beating, to create a pattern of scar tissue that keeps electrical impulses on their intended course.
Atrial fibrillation is the rapid, erratic beating of the atria, the two upper chambers of the heart. During atrial fibrillation, the atria quiver instead of beating rhythmically when the electrical impulses that cause them to contract travel through the heart in chaotic fashion.
The function of the atria is to pump blood to the lower chambers of the heart, the ventricles. But when the atria don’t beat normally, blood collects in the atria and moves through the heart sluggishly and intermittently. This increases the risk of blood clots, which can cause strokes.
About 15 percent of strokes are the result of atrial fibrillation. In severe cases, the condition also can cause heart failure.
Most common in older adults, atrial fibrillation affects an estimated 5 million Americans over 65. It can be caused by anything that damages the heart muscle including hypertension, hyperthyroidism, infections, and various heart and lung diseases.
The most common symptoms are weakness, lightheadedness, shortness of breath and chest pain. Some people with atrial fibrillation are severely debilitated while others have no symptoms at all.
Physicians use a variety of medications to slow the rapid heart rate associated with atrial fibrillation, and they sometimes use electrical shock to try to jolt the heart back into normal rhythm. In addition, various methods have been developed to block stray electrical impulses and to guide electricity onto the correct pathways through the heart.
Maze-like patterns of scar tissue, which serves as a barrier to electrical conduction, are created by cutting or, more often, cauterizing the heart muscle.
Dr. Kiser developed a new version of the maze procedure called Ex-Maze in collaboration with other surgeons. The Ex-Maze creates a more extensive pattern of scar tissue and controls the heart’s electrical impulses more effectively.
A major advantage of the Ex-Maze procedure is that the heart muscle can be burned while the heart is beating.
“Other surgeons who do the maze procedure either do half of a maze or they stop the heart to do it and have the patient on a heart-lung machine,” Dr. Kiser says. “But 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, we can see the atrial fibrillation correct to a normal heart rhythm during the procedure. We are finding that if we can convert patients out of atrial fibrillation in the operating room, we have a remarkable success rate.”
||Andy Kiser, M.D., a cardiothoracic surgeon at FirstHealth Moore Regional Hospital, uses a model to explain the Ex-Maze procedure that he developed to treat atrial fibrillation during a June 19 media day program.
How the Ex-Maze works
The Ex-Maze device cauterizes the heart muscle with heat generated by radio frequency. The heating coil is inside a plastic tube that is pressed against the heart. A saline solution flows continuously through
the tube, preventing the surface of the heart from being burned while the deeper muscle is cauterized. A vacuum system keeps the device in constant contact with the heart to ensure that the pattern of scar tissue is consistent and unbroken.
The Ex-Maze device was developed by nContact Surgical, Inc., a company based in Morrisville, N.C.
Dr. Kiser began doing the Ex-Maze procedure on patients at Moore Regional last winter, initially performing it only as an open-chest procedure when the patient was undergoing some other heart procedure, such as valve repair or bypass surgery. This past June, in collaboration with Polish and German heart surgeons, he performed the world’s first minimally invasive Ex-Maze procedure on a patient in Krakow.
Instead of requiring the chest to be opened, the minimally invasive procedure can be performed through four small incisions. Dr. Kiser was scheduled to begin using the minimally invasive technique to correct atrial fibrillation in some patients at Moore Regional in late summer.
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.
“These other maze technologies have not provided a comprehensive solution to atrial fibrillation, and the number of people treated with these technologies represents less than 1 percent of the total population of atrial fibrillation patients,” Dr. Kiser says.
John Krahnert, M.D., chief of Cardiac Surgery at Moore Regional, sees the development of the Ex-Maze procedure as a significant breakthrough.
“The power of this procedure is in taking new technology and combining it with years of atrial fibrillation research to create a new procedure for patients who have had no good treatment alternatives,” he says.
Heart surgeons in other parts of the country have begun to use the Ex-Maze device and the scar tissue pattern that Dr. Kiser developed. Among the first to adopt the new procedure were groups of surgeons in Chicago, St. Louis and Sacramento, Calif.
Dr. Kiser has been performing heart surgery at Moore Regional since 2000. A member of the Pinehurst Surgical physician group, he is chief of Thoracic Surgery at Moore Regional and medical director of the Chest Center of the Carolinas. He also is a clinical assistant professor of surgery at the Brody School of Medicine at East Carolina University.
For more information on the Ex-Maze procedure for atrial fibrillation, call (800) 213-3284 toll-free or click here.
|A patient story
In late December, Paul Raisig, 74, began feeling a throbbing in the side of his throat and a slight pain in his chest. Tests showed that he had four blocked coronary arteries and atrial fibrillation.
Raisig became one of the first 10 patients at FirstHealth Moore Regional Hospital on whom Andy C. Kiser, M.D., performed his new Ex-Maze procedure to correct atrial fibrillation. Immediately following that 30-minute procedure, John Streitman, M.D., who joined Pinehurst Surgical last year, performed quadruple bypass surgery to restore normal blood flow to Raisig’s heart.
After nine months, Raisig, who lives in Harnett County, N.C., remains free of atrial fibrillation—with no more chest pain and no more throbbing in his throat.
According to Dr. Kiser, some patients with atrial fibrillation may never have symptoms related to their disease while others are completely debilitated. These people may be unable to live their life normally because they develop a heart rate that is too rapid when they exercise or they may have severe shortness of breath with exertion.
“I am very pleased with everything that was done,” Raisig said. “Everyone was so professional; I’m sure I would not be here today if it hadn’t been for them.”