Problems with the two heart valves -- the mitral valve that controls the flow of blood between the two left chambers of the heart and the aortic valve that controls the flow of blood into the heart -- are common among old people, and so is surgery to replace a damaged valve with an artificial one.
Most commonly, surgeons saw open the breast bone to get at the heart and do the replacement. Some centers perform what is called minimally invasive surgery, which requires just a four-inch incision. However, many people with valve problems are too sick or too old to withstand the rigors of an operation. The new procedure, which eliminates surgery, is designed for them.
"This procedure is early-stage technology, but it has a lot of potential for the future," says a statement by Dr. Martin Leon, director of the Cardiovascular Research Center at Lenox Hill Hospital in New York City, who described the technique Jan. 20 at the 15th Annual International Symposium on Endovascular Therapy in Miami Beach, Fla. "If in the future we can demonstrate that these valves are durable, that we can do the procedure repeatedly, reliably and safely, it may in fact be competitive with surgical valve replacement in many circumstances."
The procedure uses a new type of replacement valve specially designed for the purpose. It is placed at the end of a flexible catheter that is inserted in the femoral vein in the groin and is guided to the diseased valve. It is put in place by inflating a balloon at the end of the catheter.
The procedure has been done just once, Leon told the meeting, on a 57-year-old Frenchman with a badly damaged aortic valve and other medical problems that made surgery impossible. After the procedure, done at the Hopital Charles Nicolle in Rouen, the man's condition improved considerably, and he was able to resume some normal activities. However, he died four months later of complications that were not related to the procedure or to his heart condition.
Clinical trials of the procedure will begin in the next few months in Europe and later this year in the United States, Leon says.
A formal trial aimed at getting U.S. Food and Drug Administration approval of the technique probably will begin at the end of the third quarter of this year and will be conducted at several medical centers, he says.
Meanwhile, Dr. William O'Neill of William Beaufort Hospital in Royal Oak, Mich., will perform the technique on a "compassionate use" basis for selected patients, Leon says. It will be done "on patients who have no other alternative " and "are desperate," he says.
Such a procedure is badly needed, says Dr. Barry T. Katzen, medical director of the Miami Cardiac and Vascular Institute and chairman of the symposium, because "patients are living longer because of improvements in medical techniques and we are seeing more and more heart disease, including valve conditions. As the population ages, we are seeing these problems with increasing frequency."
This is "very early-stage research," Katzen cautions, and at best it will not be widely available for three to five years. But "this technology has great promise and it opens an area that is entirely new," he says.
The procedure can be used to replace either the mitral or the aortic valve, Katzen says, but now efforts are concentrating primarily on aortic valve replacement.
If it succeeds, it will not replace conventional surgery, Katzen says: "It is a procedure to be used only in patients who have no alternative and would die if it is not done."