Grant To Aid Researchers In Developing Artificial Heart
28, 2000 -- Heart 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 University of Virginia professor of mechanical engineering,
and his colleagues at U.Va. and in Utah are working to develop such
an artificial heart.
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 principals include cardiologists formerly associated with
the University of Utah.
Don B. Olsen, president of the Heart Institute, notes that the grant
will cover about half the cost of developing the current prototype
into a model ready for clinical trials. MedQuest Products Inc.,
a medical device company also located in Salt Lake City, has agreed
to raise the other half of development costs.
technology is protected by pending patents held by the University
of Virginia Patent Foundation.
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" artificial
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 medical
a previous prototype of an artificial heart, Utah researchers had
used ball bearings to operate the propeller-like "impeller," or
rotating blade, that moved the blood through the pump. But the ball
bearings damaged the red blood cells. So, the Utah team sought to
create a new prototype
that used magnetic bearings, which would allow the impeller to be
suspended in the blood flow, reducing friction and eliminating damage
to the blood cells. In 1991, the Utah artificial heart researchers
sought Allaire's expertise at the Center for Magnetic Bearings,
at U.Va.'s School of Engineering and Applied Science.
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 electro-magnets, Allaire said.
A hollowed-out interior will hold the impeller, a lightly fluted,
that will spin on a center pin at about 3,000 rpm. Heart patients
with the devices would wear external batteries in a vest to supply
the necessary power.
previous prototype, CFVAD-3 (Continuous Flow Ventricular Assist
Device), was essentially the shape and size of a hockey puck, made
of rust-resistant titanium and weighing about three pounds. An even
earlier version, the CFVAD2, weighed about 15 pounds and was about
4 inches by 7 inches.
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 to operate.
U.Va. team 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.
more information contact Paul Allaire at (804) 924-6209, or at email@example.com.
Charlotte Crystal, (804) 924-6858