A new study indicates a non-surgical procedure for replacing a bad aortic valve has a better outcome for high-risk patients than having open-heart surgery. The results of the study were announced Saturday at an American College of Cardiology conference in Washington, the Associated Press reports.
The study, which was funded by Medtronic, focused on that company's CoreValve system, in which a new aortic valve is implanted with a catheter inserted through an artery in the patient's leg. After one year, nearly 86 percent of patients who received the Medtronic device were still alive, compared with 81 percent of patients who underwent open surgery, the study found.
The results prompted some doctors to predict that in the near future, far fewer people will undergo the traditional operation, according to the AP.
"It's going to be very hard to tell a patient that if they need an aortic valve, surgery is going to be their best option," said one of the conference leaders, Dr. Prediman K. Shah of Cedars Sinai Heart Institute in Los Angeles.
Several hundred thousand Americans have a bad aortic valve, which can stiffen and narrow with age, keeping blood from passing through as it should. Until a few years ago, the only solution was open heart surgery, to remove the bad valve and sew in a new one.
That changed in 2011, when Edwards Lifesciences won federal approval for an expandable valve that could fit in a catheter into a leg artery, guided to the heart and placed inside the old valve, the AP reports.
Medtronic's CoreValve was approved in January for use in the U.S. to treat patients that were too frail to endure open heart surgery, known as extreme-risk patients, Reuters reports. The latest results involved high-risk, or less ill, patients. Edwards Lifesciences has FDA approval to treat patients in both categories.
The new study involved 747 patients who had a high risk of dying up to a month after surgery of 15 percent. The average age of patients in the study was 83.2 years old, and the study enrolled a nearly equal number of men and women, the Star Tribune reports.
The results surprised some doctors because a study of the Edwards Lifesciences device found the catheter approach to be have about the same outcome as open surgery, not better, said the Wall Street Journal. Patients with the Edwards Lifesciences valve also had a higher rate of stroke than patients who underwent surgery.
Medtronic is likely to try to use the results to win more market share if the device is approved for high-risk patients, said Glenn Novarro, a medical devices analyst with RBC Capital Markets, according to the Wall Street Journal. Wall Street analysts project Edwards Lifesciences to control 60 percent to 70 percent of the U.S. market, but that is now likely to go down to around 50 percent, he said.
“Somewhere in the product labeling will be the word 'superior,' and Medtronic’s marketing team will go out and say our valve was superior to surgery,” Mr. Novarro said.
Two-year follow-up is not complete, but "we are certainly encouraged" that trends appear to be continuing, said one of the study's leaders, Dr. David Adams of at New York's Mount Sinai Hospital.
The study was paid for by Medtronic, and many study leaders consult for Medtronic, Edwards or other heart device makers. Results also were published online by the New England Journal of Medicine.
Doctors say both companies' artificial valves need more long-term study to see if they hold up as well as the ones implanted surgically, which typically last 20 years. Other firms also are testing catheter-placed valves.