Sunday, October 11, 2009

American Journal of Cardiology


A Race in Cardiology(U.S.’s First Catheter-Inserted Heart Valve) between two major companies, Edwards Lifesciences and Medtronic:

A race is on to develop the potentially next big thing in heart surgery: a replacement valve that can be implanted through thin tubes known as catheters rather than by traditional open-heart surgery.
The contest pits two major companies, Edwards Lifesciences and Medtronic. Analysts estimate a market for the product that could exceed $1.5 billion within six years. But if the valves catch on, their benefits for the nation’s aging population could be substantial — even if the impact on the nation’s health care bill may be hard to calculate.

The new valves — which make it possible to repair the heart without the rigors of chest-opening surgery — have been available in Europe for about 18 months, with sales of about $100 million split about evenly last year between the two companies. While doctors say that the early results have been promising, they add that it is too early to gauge the technology’s long-term benefits.

In the United States, the devices are currently being tested in older, critically ill patients in clinical trials. Many medical experts and financial analysts predict that if the devices live up to their makers’ claims, they could revolutionize valve replacement, a common heart operation, and extend the lives of thousands of frail patients who are not now considered candidates for surgery.

The development of the new valves makes it clear that even as Congress debates ways to control the nation’s skyrocketing health costs, medical technology continues to advance in ways that may drive up health care spending even further with costly new procedures that can enable more people to live longer. Most heart valve replacements involve people of Medicare age.

The race between Edwards and Medtronic involves one of the heart’s four valves — the aortic valve, which controls blood flow into the aorta from the heart. Aortic valves were involved in the vast majority of the estimated 95,000 open-heart surgeries in the country last year to replace a diseased valve with a new one, according to Millennium Research, a consulting group.

An estimated 20,000 people die annually from valve-related disease, including those too sick to withstand surgery. The new valves from Edwards and Medtronic would be meant to enable more such patients to have life-saving valve replacements.

The new units, known as percutaneous heart valves, are implanted through catheters, in much the same way that artery-opening stents are. A catheter holding a compressed replacement valve is inserted through a small incision in the groin or, if blood vessels are blocked, through an opening near the ribs. The catheter is then snaked through a vessel into the heart and the new valve is released, essentially compressing the diseased tissue and moving into its place.

But the new technology would not be inexpensive.

The current cost of heart valve replacement surgery is about $50,000, a sum that includes surgical fees, hospital costs and the price of a replacement valve, which sells for about $5,000. By contrast, the new valves currently sell for up to $30,000. Both Edwards and Medtronic, though, say that the higher prices for the valves would be offset by lower costs from anticipated shorter hospital stays.

Edwards, which recently enrolled the last of about 1,000 patients in a major trial of its valve that is already under way, has a significant head start. Its device, if successful in that study and subsequently approved by the Food and Drug Administration, could be on the market in the United States in two years.

Medtronic entered the race only in April, by purchasing CoreValve, a privately held company, for $700 million. Although the company hopes to start a major trial next summer, it is still discussing the study’s design with the F.D.A.

“It is a two-valve race, with Edwards in the lead in the U.S.,” said Kristen Stewart, a medical device industry analyst with Credit Suisse.

If the new valves prove beneficial in the sickest of patients, the next big question will be whether they should be used in patients who are now considered suitable candidates for open-heart surgery. Many heart specialists, pointing to the rapid proliferation of other expensive medical technologies, are urging caution. They point out that the success rate of conventional open-heart surgery is extremely high and that the replacement valves now in use are highly durable, lasting 10 to 15 years.

With only a few years of data on the new valves, it remains uncertain how long they can last. That is why the studies so far are focusing mainly on people who are not candidates for conventional surgery.

“We are willing to put in a valve that will not last as long in a patient who is at high surgical risk,” said Dr. Robert Guyton, the chief of cardiothoracic surgery at Emory University in Atlanta, who is involved in the Edwards trial.

He and other doctors also say that the technology of implanting heart valves through catheters is still highly experimental. While complication rates are coming down as doctors gain experience, the procedure still can sometimes damage the heart or cause strokes.

“It’s like baseball, you either hit a home run or you strike out,” Dr. Lars G. Svensson, a heart surgeon at the Cleveland Clinic who is also participating in the Edwards trial.

Such risks may matter little to patients suffering from aortic stenosis, or a narrowing of the valve caused by the hardening of fat deposits. Once patients begin to experience that condition’s symptoms, including shortness of breath and dizziness, they can die in two or three years if the valve is not replaced.

That was the situation facing Henry Tipton, a 97-year-old retired naval officer who lives in Sterling, Va. About three years ago, Mr. Tipton’s doctor told him he was too old for open-heart surgery and his outlook was bleak. Then the doctor heard about the Edwards trial, which was just starting.

“I really had no alternative, so I decided to go ahead and take a chance,” said Mr. Tipton in a recent telephone interview from Utah where he was traveling with family members. “Within one day of the implant of the artificial valve, I felt completely recovered.”

0 Comments:

Post a Comment



Health Tips © 2008. Design by :Yanku Templates Sponsored by: Tutorial87 Commentcute