heart pump funded
disease is America's top killer, claiming more than 400,000 lives
each year. The most severely affected patients could be saved
by new hearts, but only 3,000 or so heart transplants are performed
each year. That leaves a number of seriously ill patients -- estimates
range from 17,000 to 240,000 annually -- who could live long,
productive lives if reliable artificial hearts were available.
Allaire, a U.Va. professor of mechanical engineering, and his
colleagues here and in Utah are working to develop such an artificial
and his associates have received a grant of nearly $4.2 million
from the National Institutes of Health to continue development
of an artificial heart pump. This new grant provides funding after
an earlier, $3 million research grant from InterMountain Health
Care, a not-for-profit corporation that runs a hospital system
in Utah, ended last month.
new grant will be split between Allaire's group at U.Va., which
is refining the mechanical aspects of the pump, and the Utah Artificial
Heart Institute, an independent research center in Salt Lake City
whose researchers include cardiologists formerly associated with
the University of Utah. The U.Va. Patent Foundation has patents
pending for the technology.
researchers are internationally known for their work in artificial
heart development and cardiac surgery. It was at the University
of Utah in 1982 that the Jarvik-7 artificial heart was implanted
in Barney Clark, the world's first recipient of a "permanent"
In 1991, the Utah artificial heart researchers sought Allaire's
expertise at the Engineering School's Center for Magnetic Bearings.
Researchers wanted to reduce the number of moving parts thereby
minimizing the chances for mechanical failure. Current pulsating
heart pumps have more than 100 moving parts and associated reliability
problems. They typically last one to two years before malfunctioning,
according to Allaire. In contrast, the U.Va.-Utah prototype has
only one moving part -- the pump impeller -- boosting the device's
expected lifetime to more than 10 years, he said.
simple, circular design of the inside of the pump and a single
moving part, the impeller, also minimize the chance of thrombosis,
or potentially fatal blood clotting, according to Allaire.
U.Va.-Utah team's current prototype, the CF-4 or "HeartQuest,"
will probably be made of some type of plastic, to make it as lightweight
as possible, and operated by eight electromagnets, Allaire said.
U.Va. engineers have yet another experimental version of the heart
pump on the drawing board, the CF-5, which will use permanent
magnets instead of electromagnets and require even less power
The U.Va. team includes biomedical engineering professor Milton
Adams, mechanical engineering professor Ronald D. Flack Jr., mechanical
engineering professor James C. McDaniel Jr., Gang Tao, associate
professor of electrical engineering, and Houston Wood, associate
professor of mechanical engineering. U.Va. will devote its share
of the grant to covering the costs of testing the model now under
development and building new, smaller and more sophisticated prototypes
of the heart-assist devices.
some patients receive artificial, "bridge-to-transplant,"
hearts. These grapefruit-sized devices enable patients to survive,
in bed, for six months to a year, waiting for a compatible human
heart to be found. But these artificial hearts are only a temporary
solution. No "permanent" (that is, offering a life of
10 to 20 years) artificial hearts have been approved for routine
use by the U.S. Food and Drug Administration, which regulates