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Heart surgeon O. H. Frazier
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Pioneering Surgeon: O. H. Frazier
Dr. O. H. Frazier has done more heart transplants and more implants of left
ventricular assist devices than anyone else. Chief of Cardiopulmonary
Transplantation at the Texas Heart Institute in Houston, Frazier also stands
in the vanguard of researchers testing various partial and total artificial
hearts, in hopes of saving the lives of the hundreds of thousands of people
in the U.S. who die every year from coronary heart disease. Here he talks with
NOVA producer Sarah Holt about everything from the early Jarvik-7 artificial
heart (the one implanted in Barney Clark, who in 1982 became the first recipient
of a permanent artificial heart) to the new AbioCor total artificial heart,
the first that will be completely enclosed within the body.
NOVA: Will the heart be the first organ that we succeed in replacing?
Frazier: As far as an internal organ that we can replace, the heart certainly
seems to be the organ that will be first. Some research is ongoing with both livers
and lungs, but that technology is very early in development. The heart is still a
complicated organ to replace (much more than a simple pump) but the technology is better
developed. The heart has many properties, including hormonal properties, that we never
appreciated when we first started doing this research. In the near future, I think
that the heart will be the only organ that will be replaced as a totally artificial
or man-made substitute for an internal human organ.
NOVA: And why is that so important?
Frazier: It's important from a lot of standpoints. Too many patients die
prematurely. Today, if an active working person in his or her 70s dies from a
heart attack, that death is premature. The main cause of premature death in the
U.S. and the world is heart disease. Even though we smoke less, eat more healthful
foods, and exercise, the incidence of heart disease has not decreased. If anything,
it seems to be increasing. In addition, heart disease is a very common cause of
death in women as well as men—in fact, heart disease causes death in more women
under the age of 60 than breast cancer does—and it also plagues children and young adults.
NOVA: Heart transplantation is not enough?
Frazier: Heart transplants were a remarkable advance. I have the dubious honor
of probably doing more than anyone, because I'm the only one at our center who does
transplant operations. I've done over 700 heart transplants, but I have very mixed
feelings about it. Heart transplantation is a wonderful technology, and it helps
patients, but it's a rather temporary solution. All of us in the field have been
rather discouraged by the limitations of long-term survival, particularly in our young patients.
Frazier has done
more heart transplants than anyone else.
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It's especially hard when we do a transplant in a young child. With a successful
heart transplant, a young child (2-3 years old) grows to be 13 or 14, and then may
die or require a second transplant. The parents are always grateful, but the situation
is really difficult.
It's the same for the young adults. I have patients 25 or 30 years old. They appreciate
living another eight to ten years. But they want more, and we want more. Probably the
most emotionally satisfying patients we do heart transplants for are those in their
60s, because they are more satisfied with the additional time, which is enough to get
them their three score and ten.
NOVA: Aren't there only about 2,000 hearts available for transplant every year?
Frazier: Yes, and that number has gone down instead of up. We have fewer homicides,
fewer automobile accidents. The helmet laws have made a significant difference in the
number of motorcycle fatalities. In the 1980s, hardly a week went by without our seeing a
donor who had been killed on a motorcycle. We haven't seen that in years. This is good,
actually. After all, it's rather disquieting to have to depend on the misfortune of others
for these patients to benefit. In addition, many of the donors we do have are older and
more compromised than in previous years.
Also, the cost of heart transplantation is enormous, and there's no way of lessening
the cost. A heart transplant requires a team of people in the operating room and a
large team of people to take care of these patients after their transplant. For
all of these reasons, it's very important that research into artificial hearts continues.
NOVA: What are your thoughts on the Jarvik-7 artificial heart?
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The Jarvik-7, here held by its designer, Robert Jarvik, was the first total artificial heart to be implanted in a patient.
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Frazier: The Jarvik-7, which was designed for long-term use, was an outgrowth
of our experience in temporary total artificial hearts as bridges to transplant.
Early on, we implanted two total artificial hearts and an LVAD as bridges to transplant
(1969, 1978, and 1981). The Jarvik-7 was introduced before it became apparent that the
immunosuppressive drug cyclosporine would make transplants feasible again and,
importantly, allow bridges to transplant to be successful.
Most of us doing research in the field of artificial hearts were not optimistic
about the use of the Jarvik-7 heart as permanent therapy. The calf experiments with
the Jarvik-7 showed limited survival. There were frequent problems with infections,
with durability, and with strokes or blood clots. So we were a bit skeptical of the
outcome. I think there were even some public statements made to that effect by both
Dr. [Michael] DeBakey and Dr. [Denton] Cooley at the time this trial began.
But the remarkable thing about that trial was really how well the patients did. All
of the patients were dying, and the pump lasted far longer and had far fewer
problems than we had anticipated. Of course, all those patients had a lot of
spirit and courage as well. We were encouraged by that, because the device was
loud and bulky and actually rather traumatic with its forceful pumping. We thought
that these problems might be difficult for the patients to accept, but they seemed
to accept them very well.
NOVA: So a lot was learned from the Jarvik-7?
Frazier: Yes. I think all of us in the field were stunned because the heart
worked so well. I saw those patients, and it was absolutely remarkable that they
lived as long as they did. One survived about 600 days. I don't think any of the
LVADs have lasted much longer. [LVADs are left ventricular assist devices—partial artificial hearts that take over pumping blood for the left ventricle.]
That showed the durability of the human body and the human spirit.
NOVA: Yet after Jarvik-7, didn't many researchers in the field begin focusing
strictly on developing LVADs?
Axial-flow pumps are tiny enough to fit inside the human heart.
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Frazier: That's right. Historically, we thought the artificial heart would be
the answer. When I was in medical school, the head of our research team was one of the
most experienced people in the field. He told me in 1965 that by 1980 there would be
100,000 Americans with a total artificial heart. Of course, there weren't. As the
difficulties with the total artificial heart became more apparent, we reverted to
the use of the LVAD for a lot of reasons, one of which was that it was sImpler.
We could time the pumping of the LVAD by using the action of the native heart.
And by leaving the native heart in place, we didn't have to deal with the space
confinements that trying to replace the whole heart gave us.
NOVA: A real breakthrough in developing LVADs came in 1988 with Richard
Wampler's axial-flow pump [a tiny, continuous-flow pump that allows weakened
hearts to recover]. Did that pave the way for the new continuous-flow LVADs
like the Jarvik-2000 and the DeBakey VAD?
Frazier: Yes, it really opened up this field. Wampler designed it for
use as a temporary pump: a very small, continuous-flow pump that would take
the blood out of the heart when the heart failed after a sudden heart attack
or right after heart surgery, and pump for a few days to allow the heart to rest.
Our first use of the Hemopump in April 1988 was very dramatic because it showed
us that patients could live without a pulse. I had one little boy who lived for
about three days without a pulse at all. He was very small, and this tiny pump
could take over his entire circulation. He woke up, he ate popsicles, and he
did very well for a period of time until his heart had recovered enough to
start beating again.
With the Hemopump, we also learned that we could have a very high rate of
flow and turbulence in the bloodstream without destroying the blood cells,
which was a very important finding. That stimulated others to develop continuous-flow pumps.
Continue: The advantages of continuous flow
Map of the Human Heart |
Amazing Heart Facts
The Artificial Human |
Pioneering Surgeon |
Operation: Heart Transplant
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