On this day in History – Robert Koffler Jarvik was born

Robert Jarvik, MD is widely known as the inventor of the
first successful permanent artificial heart, the Jarvik 7. In 1982, the first
implantation of the Jarvik 7 in patient Barney Clark caught the attention of
media around the world. The extraordinary openness of this medical experiment,
facilitated by the University of Utah, fueled heated public debate on all
aspects of medical research. But as doctors learned how to achieve excellent
clinical outcomes in subsequent patients with the Jarvik 7, the press and
public largely lost interest in the subject. As a result, outdated and
erroneous accounts have made their way into mainstream discussions of the
Jarvik 7 time and time again. 

Robert Jarvik
 Artificial Hearts in Context

In essence, two types of artificial hearts exist: the total
artificial heart — which is implanted after the natural heart is removed — and
the ventricular assist device — which is implanted to assist the natural heart,
leaving the patient’s own heart in place and still functioning.

“Removing a person’s heart is one of the most dramatic
surgical procedures one can imagine,” says Dr. Jarvik, who began
developing a tiny ventricular assist device, the Jarvik 2000, in 1988. “It
is no surprise that more public attention is given to replacing a heart than to
assisting one. But consider this question: If you had a failing arm or leg,
would you rather have the best-possible artificial limb or a device that
allowed you to keep your own arm or leg?”

The question is rhetorical. But while ventricular assist
devices find wider application in patients than total artificial hearts,
experts view the two as complementary treatments. For example, a total
artificial heart is required when an assist device will not do, as in cases of
biventricular failure when both sides of the natural heart falter.

In the 60s and 70s, mechanical hearts were being developed
by the National Institutes of Health (NIH) but were largely unknown to the
public. Then in 1967, Christian Bernard performed the first human heart
transplant, an event that generated worldwide interest: People were suddenly
aware of heart replacement as a way to treat a failing heart. In 1969, Denton
Cooley performed the first implantation of a temporary total artificial heart, and
the primitive device sustained the patient for almost three days until a donor
was found through an urgent appeal in the press. After another decade and a
half of NIH-supported research, the Jarvik 7 heart became the first total
artificial heart implanted as a permanent replacement for a hopelessly diseased
natural heart.

The First Jarvik 7 Patients

At the University of Utah on December 2, 1982, William
DeVries, MD implanted the Jarvik 7 total artificial into Barney Clark, a
Seattle dentist who volunteered to undergo the pioneering procedure because he
wanted to make a contribution to medical science. Dr. Jarvik recalls that,
before the surgery, Dr. Clark told doctors that he didn’t expect to live more
than a few days with the experimental heart, but he hoped that what the doctors
learned might help save the lives of others someday.

Dr. Jarvik, who headed the company that manufactured the
Jarvik 7 heart, agreed with University administrators to give no information to
the press directly: no press releases and no interviews. Information would flow
through the University press office, instead. The stated goal was to adhere to
the highest ethical principles and to conduct this important medical research
openly, with no effort to influence or restrict the press. Little press was
desired or expected. The University held a briefing before the historic
surgery, and attendance was moderate.

“The news about Barney Clark stunned the doctors by
making headlines around the world”, Dr. Jarvik says. “Enormous public
interest developed, and hundreds of reporters converged on Salt Lake City to
cover the story, and the University began to give them daily briefings, which
were completely uncensored. All medically significant events in the
post-operative course were reported, successes and setbacks alike.”

The briefings were educational and contained much medical
information, including explanations of basic physiology, interpretations of
laboratory tests and x-rays, and lengthy question-and-answer sessions. All of
the complications were fully reported, as well as the effectiveness of the
mechanical heart at maintaining Dr. Clark’s normal blood flow and sustaining
his life.

“The sheer volume of information and the extraordinary
degree of transparency created a sort of medical experiment in a
fishbowl,” Dr. Jarvik says. The University of Utah achieved its research
and educational goals, but the press coverage seemed to leave its readers with
unreasonable hopes and expectations: Many began to believe that artificial
hearts would soon be commonplace and all but solve the problem of heart
disease. The intense attention also attracted critics who apparently knew
nothing of Dr. Clark’s generous intentions and labeled him a “human guinea
pig.” Later, Dr. Clark’s widow attempted to change this misimpression in
order to give her husband the humanitarian credit he deserved. But Mrs. Clark
received much less press than the critical commentary, and her mission
ultimately foundered. Before another case could be conducted, Dr. DeVries, the
surgeon, accepted an offer to join the research program at Humana Hospital in
Louisville, Kentucky, and took his expertise there.

The next several implantations of the Jarvik 7 heart,
conducted by Humana — a national hospital chain — were handled like the first:
with the release of extensive medical information and an open press policy. The
second Jarvik 7 implant took place in 1985. Bill Schroeder, the patient, did so
well initially that when President Ronald Reagan phoned him with get-well
wishes a week later, he asked the president why his social security check was
late. (It was hand-delivered the next day.) Mr. Schroeder gave optimistic
interviews to reporters and even joked that his noisy drive console
“sounded like an old fashioned thrashing machine.” But only two weeks
after surgery, he suffered a serious stroke that left him unable to speak. Mr.
Schroeder later moved from the hospital and lived with his wife in a nearby
apartment, which had been outfitted with the special equipment he needed,
including an air compressor and emergency generator. When traveling, he used a
portable, compressed-air power system, which weighed about fifteen pounds.
During his time on the Jarvik 7, he visited his hometown in Indiana and rode
down Main Street in a parade, attended a basketball game, and went fishing, but
in a limited way: He had many medical problems, including other serious strokes
and infections. In all, Mr. Schroeder lived 620 days with his heart function
restored but handicapped by his complications.

Three other patients received the Jarvik 7 heart for
permanent use over the next year — two more in Louisville and one in Sweden.
One patient died of bleeding a week following the operation; the others lived
10 months and 14 months. As it turned out, the Swedish patient was a man
accused of tax evasion, but after his heart was removed, he was declared
legally dead because under Swedish law, a person was dead when his or her heart
stopped beating. The charges against him were officially dropped. The day he
received the news, the patient was elated: He joked to his doctors that the old
saying about nothing being certain but death and taxes isn’t true.

The Jarvik 7 Today

After the first five permanent cases, the Jarvik 7 heart
became more widely used as a temporary total artificial heart, bridging
patients to transplant. The sixth patient lived five years after a donor heart
was found, and the seventh patient lived eleven years with his donated heart.
Another patient was bridged from the Jarvik 7 heart to a human heart that gave
him fourteen more years of normal life. The press was unaware of these
successes, or perhaps considered the subject old news, which, Dr. Jarvik says,
was “more than fine” with the doctors involved. But as time went on,
the press began reporting erroneously that use of the Jarvik 7 heart had halted
after the first five. Later this turned into reporting erroneously that the
Food and Drug Administration (FDA) had banned its use. Still later, this turned
into reporting erroneously that the Jarvik 7 heart was a failed experiment: 

The
press had begun to believe its own errors.

Since 1982, more than 350 patients have used the Jarvik 7
heart, and it remains in use today. The first few patients lived an average of
10 months (when their life expectancy was only days to weeks). Complication
rates were high. “That’s where the press stopped doing research and
checking facts and instead began to publish mistake after mistake after
mistake,” Dr. Jarvik notes. All aspects of the experience, from the role of
public funding of the research, to the ethics of human experimentation, were
debated, but often on a foundation of misinformation. Newspaper and magazine
articles with outdated and mistaken accounts appeared. Books with numerous
errors were published. In the meantime, doctors gained experience with the
Jarvik 7 and learned how to manage their patients more effectively and with
fewer complications.

“Knowledgeable doctors watched with amazement as
glaring errors appeared in print and then were repeated again and again as
newspapers and magazines copied earlier stories and each other and didn’t take
the time to get information from original sources,” says Dr. Jarvik.
“Very rarely did I receive a phone call to check the facts. For example,
the press wrote repeatedly that Dr. Clark died of a stroke. In fact, he never
had a stroke at all. The press wrote over and over that the console a patient
needed to power the heart was ‘as large as a refrigerator.’ In fact, the home
console is about half that size, but more significantly — the portable power
system was only the size of a briefcase.”

And there’s more, says Dr. Jarvik. “The press also
wrote that the Jarvik 7 heart caused a high rate of strokes and infections. The
press didn’t notice that as more cases were done, these rates plummeted, yet
the device was the same. So the device alone was never responsible for the
earlier complications. Rather, doctors needed to learn how to manage their
patients more effectively: That is the point of such research in the first
place.”

Perhaps the most glaring error of all is one that pops up
from time to time in the diatribes of some self-proclaimed pundits: that the
Jarvik 7 heart was a failed experiment. In fact, it has achieved the highest
success rate of any type of artificial heart or assist device that has ever
been developed.  Today, the Jarvik 7 heart is available at
about ten medical centers in the United States, Canada, France, and Germany
under the name CardioWest total artificial heart. (Ownership has changed hands
several times, but the device 
design remains essentially unchanged.)


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Posted on May 11, 2015, in Useful Information. Bookmark the permalink. Leave a comment.

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