Filter May Help Treat Heart Failure
Study Shows New Device May Have Edge Over Treatment With Diuretics
March 13, 2006 (Atlanta) -- A device that flushes out excess salt and water from the blood beat out standard diuretic treatment in people hospitalized with heart failure, according to the first study of its kind.
"Up to now, diuretics have been the mainstay of therapy [for such patients], but amazingly they have never been tested in a randomized, controlled trial," says Maria Rosa Costanzo, MD, of the Midwest Heart Foundation in Lombard, Ill.
The new study suggests that the newer treatment could help as many as 90% of the 1 million patients hospitalized for heart failure each year to breathe easier and generally feel better, she tells WebMD.
The study was presented here at the annual meeting of the American College of Cardiology.
Advantages of New Treatment
Heart failure occurs when weak hearts pump less forcefully, causing a backup of fluid in the lungs and other areas of the body. Diuretics are "water pills" that help reduce the congestion by making the kidneys rid the body of excess fluid. But diuretics can cause problems with kidney function and often stop working over time.
With the newer technique, blood is removed through an IV line placed in the leg or arm and circulated through a filter that removes excess fluid. The excess salt and water are discarded, and blood cells and other important components are returned to the patient. The device can remove up to a pound an hour of excess salt and water from the bloodstream, Costanzo says.
"The treatment can relieve fluid overload quickly, safely, and predictably, and leads to sustained benefits," she tells WebMD.
Reductions in Hospitalizations
For the study, 200 hospitalized heart failure patients were randomly assigned to either the filter device, known as Aquadex FlexFlow, or diuretics.
Forty-eight hours later, filtration was associated with 30% more fluid loss and 44% more weight loss than diuretics.
And by 90 days later, only 18% had to be rehospitalized vs. 32% of those getting diuretics. Usually, a person hospitalized for heart failure has a 30% chance of being readmitted over the first three months, Costanzo says.
People on the device were also only about half as likely to have to go to the emergency department or have an unscheduled office visit over the first 90 days.
Clyde Yancy, MD, professor of medicine at the University of Texas Southwestern Medical Center in Dallas and a spokesman for the American Heart Association, says the one drawback was that people on filtration were just as likely to be short of breath as those on diuretics.
Nevertheless, "this is an exciting technology," he tells WebMD, adding that new treatments for heart failure are desperately needed. "And it didn't harm kidney function, which is very important."