An artificial heart valve could help some people too frail to survive having their chest opened in surgery, a new study suggests.

The study published in Thursday's New England Journal of Medicine looked at 358 patients with severe aortic stenosis, which prevents the heart's aortic valve from fully opening. Study participants had an average age of 83 — too old or poor in health to have regular valve replacement in open-heart surgery.

Dr. Martin Leon, director of the Center for Interventional Vascular Therapy at New York-Presbyterian Hospital and Columbia University Medical Center in New York City, and his co-authors randomly assigned people to the standard therapy with medication and a temporary balloon procedure for comfort or the new procedure.

The new procedure, called transcatheter aortic-valve implantation or TAVI, threads a catheter through the femoral artery to the heart. When the catheter reaches the aortic valve, the surgeon opens up a balloon to prop the old valve open without replacing it.

Without open-heart surgery for valve replacement, about half of people with aortic stenosis die within two or three years of diagnosis.

In the first month, five per cent of the valve recipients died, compared with 2.8 per cent of the control group.

Stroke worry

After a year, half of patients who didn't get the new procedure had died of various causes compared with 30 per cent among those who had it.

In terms of adverse events, five per cent of those in the valve group had strokes in the 30 days after the procedure compared with one per cent in the control group — a difference that is concerning, said Dr. James McClurken of Temple University in Philadelphia.

The less invasive option will "possibly be a game-changer," said Dr. Robert Bonow of Northwestern University's Feinberg School in Medicine in Chicago, who monitors the valves' development for the American Heart Association and has consulted for the device maker. 

Standard heart valve replacement costs upward of $50,000 US, mainly from surgical and hospitalization fees. Transcatheter valves are anticipated to cost $20,000 US to $30,000 US but could lower hospital bills compared with open-heart surgery.

The new device has not been approved by regulators in the U.S. but has been in Europe. Health Canada's website lists it as available under special access.

The manufacturer of the device, Edwards Lifesciences Corp., paid for the study at 21 hospitals. Many of the researchers have received fees from that company or competing heart device makers.

With files from The Associated Press