Jarvik Heart, Inc.

Success Story:
Jarvik Heart, Inc.
EDM I Milling I Laser Texturing I Tooling & Automation I Customer Service

The Best Way Usually Isn’t the Easiest
For some manufacturing sectors, pursuing the easiest means
of production is an acceptable goal. For manufacturers of
sensitive medical devices, such an approach is rarely possible,
let alone preferable. Jarvik Heart, Inc. of New York defines its
goal as pursuing the best solution and then working to make
it possible. A recent installation of a GF AgieCharmilles wire
EDM machine demonstrates the company’s constant commitment
to excellence, even when it is far from easy to accomplish.
Dr. Robert Jarvik possesses over thirty years of experience
in the field of medical device design and production. Working
with a team of researchers at the University of Utah in the
1970’s, he developed the Jarvik-7, the world’s first total artificial
heart designed to provide lifelong support. Since 1987,
he has continued his efforts to develop devices for people
with severe heart failure at a facility occupying four floors of
a building in Manhattan. Recently, this unique location presented
a significant hurdle in implementing the best available
production solution.
In April 2004, Jarvik Heart was awarded a $5 million contract
from the National Institutes of Health (NIH). The goal was to
develop a miniaturized version of the highly successful Jarvik
2000 VAD (Ventricular Assist Device) for use in children and
infants with congenital heart defects. At present, children with
such conditions face extremely dire odds.
There is a cumulative 50% mortality rate for the multiple
operations necessary in the first two years of life for children
with some of the more serious heart defects. After that, only
one in ten children receive a donor heart. Additionally, those
lucky few may spend years waiting, with a reduced quality of
life due to liver damage, fluid build-up in the abdomen and
other associated complications. The development of a permanent
VAD will have tremendously positive effects on these
children born with the cards stacked against them.
For nearly four years, Dr. Jarvik and his team worked tirelessly
to reduce the size of the Jarvik 2000 to the point where
it would be suitable for pediatric use. Unfortunately, smaller
designs created a host of problems.
“We found that we could not just shrink the existing design,”
says Dr. Jarvik. “With a smaller pump, we continually had
problems with thrombus formation within the device. This was
a severe problem, as it would eventually lead to premature
pump failure. A small thrombus would form around the bearings
and cause enough friction to stop the rotor from spinning.
The tiny motors don’t have enough torque to overcome this
binding force.”
Late in 2007, Dr. Jarvik made a breakthrough in the concept of
a pediatric VAD. While the exact details are confidential, it can
be said that the turning point involved a redesign of the bearings
used in the pump. Extensive calculations and initial prototype
testing suggested that the solution had been found and
the question became how best to machine the component.
It would require several sharp angles and levels of accuracy
and surface finish exceeding the capabilities of Jarvik Heart’s
existing equipment, so the team began examining its options.
“We found ourselves in a very tight spot,” says Dr. Jarvik. “Our
annual review with NIH was just over two months away and we
felt it was imperative that we be able to prove the benefits of
the new design in that time. Because of its size and requirements,
we knew the part would need to be machined on a wire
EDM. It was a matter of finding the right machine and proceeding
with its installation as quickly as possible.”
After some initial investigation into the capabilities of various
makes and models of machines, Jarvik Heart requested test
cuts from several EDM manufacturers. Based on the results,
the company chose the AC Classic V2 from GF AgieCharmilles.

The machine features the IPG-V generator that increases
pulses’ shape factor while shortening the pulse duration,
allowing it to obtain high accuracy and surface finish. These
areas are also bolstered by the machine’s unique toroids that
activate during taper cutting, which increases the wire tensile
force. The machine provided exactly the results Jarvik Heart
needed and the next challenge was obtaining the machine in
time to produce tangible results prior to the NIH review.
Once the order had been placed, GF AgieCharmilles began
preparations for an expedited delivery. This process uncovered
a significant problem. The opening to the freight elevator in
Jarvik Heart’s building was approximately 4” narrower than
the width of the AC Classic V2. Given the sensitivity of the
project, GF AgieCharmilles immediately formed a team to address
the challenge. Employees from the GF AgieCharmilles
Refurbishment, Advanced Technical Support and Northeast
Regional Service departments came together to devise a solution.
It quickly became clear that the only option was to disassemble
a machine for delivery and then reassemble it on-site.
An AC Classic V2 was delivered to GF AgieCharmilles’ Lincolnshire
facility, where it was immediately stripped of sheet metal
and peripherals. A team of technicians then disassembled the
machine, carefully identifying and marking every component,
connection and fitting. The machine made the journey to New
York in six crates.
In January 2008, four engineers from GF AgieCharmilles traveled
to Jarvik Heart to reassemble the machine. A special
hoist was created to aid in the unconventional installation.
After several days, Jarvik Heart had its new wire EDM, its
condition indistinguishable from a machine fresh off of the
production line.
Jarvik Heart’s 2008 NIH review went extremely well, with all
parties impressed by the breakthroughs the team had made.
While developed for infants, the new design has potential ramifications
for all those who suffer from life threatening heart
disease. To be effective, the pediatric VAD needed to be able
to increase its output to match the growing body of its host. In
an infant, it would require operation at 20,000 rpm to achieve
the necessary blood flow. As that child grows, the pump’s rpm
increases to drive a greater amount of blood. Initial evaluation
of the new design indicates that the pump is capable of
maintaining 70,000 rpm, pumping enough blood for an adult.
Due to its much smaller size, the new pump could considerably
reduce the risks and complexity of the surgery necessary
to implant a VAD.
“The new model holds tremendous promise,” says Dr. Jarvik.
“The fit of the bearings is so perfect that the amplitude of
radial vibrations possible is on the order of 10 to 20 millionths
of an inch. When the pump is running at 70,000 rpm underwater,
it is nearly silent and you can hold it and feel practically no
vibration.”
The pediatric VAD will soon be used in its first animal implants.
If that produces the expected results, a long period of
clinical trials will be necessary. As with all medical devices,
full acceptance and integration of the product will be a lengthy
process due to regulatory hurdles.
“Each improvement to the design of a VAD becomes somewhat
more difficult,” explains Dr. Jarvik. “Once we had a
device that proved effective for two years, people then wanted
one that would last for five. Once we cleared that hurdle,
people wanted one that would last for ten. And once one
model receives those results, the regulatory bodies want
every model to achieve those results. In effect, each success
we achieve lengthens the time it will take to develop our next
improvement.”
That challenge does not faze the team of forty employees
working with Dr. Jarvik. They recognize that the road to improving
people’s lives will always have significant hurdles to
overcome. For Jarvik Heart, the reward is worth making the
effort to always strive for the best possible results.
To further aid in meeting the deadline imposed by Jarvik
Heart, applications specialists from GF AgieCharmilles assisted
in development of the complex programming needed to
complete the prototype Dr. Jarvik had envisioned. In the end,
the part was completed to the exact specifications required.
“The AC Classic V2 delivered the precision and surface finish
demanded by the part,” says Dr. Jarvik. “We have to hold steep
angles within a 0.016º tolerance, while having the machine
provide surface finish of around 0.15 µm. It’s a demanding application
and we couldn’t do it without the innovations found in
GF AgieCharmilles’ wire EDM.”

GF Machining Solutions
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Phone: 847-913-5300
© Machining Solutions, 2015
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