Operation on Fetus's Heart Valve Called a 'Science Fiction' Success
- From: jing zhi <zhijing718@xxxxxxxxx>
- Date: Tue, 21 Jul 2009 23:26:14 -0700 (PDT)
Soon after he was born last November at Brigham and Women's Hospital,
a baby named Jack was wheeled through a passageway to Children's
Hospital, where cardiologists stood by, ready to perform a procedure
to open a narrowed valve in his heart.
To the doctors' surprise and delight, Jack did not need their help.
His aortic valve, though a bit narrow, was wide enough to do its job,
and the chambers of his heart looked healthy. Even though he had been
delivered six weeks early, he was robust and breathing on his own.
The medical team had already widened the valve once, in a daring
procedure months before, while Jack was in his mother's womb. But the
doctors were not sure the valve would stay open. Now, examining the
baby, they realized that their repair job had worked even better than
expected. They had, for the first time in the United States, corrected
a deadly heart defect in a fetus.
''We couldn't believe it,'' said Dr. Stanton Perry, one of the
cardiologists who had worked on Jack. The team was so elated, he said,
that it did echocardiograms over and over, just to watch Jack's
Jack's doctors believe that by opening the pinched valve during the
23rd week of pregnancy, they prevented a devastating disorder,
hypoplastic left heart syndrome, in which the left ventricle, the
heart's main pumping chamber, stops growing and becomes scarred and
useless. Such babies are, in essence, born with half a heart.
Untreated, the condition is fatal soon after birth. Treatment requires
extreme measures: three heart operations, with a 30 percent death rate
and a total cost of at least half a million dollars. Even when the
surgery works, the heart is still far from normal, and survivors may
ultimately need transplants. The syndrome is what drove doctors at
Loma Linda University to perform a desperate operation in 1984, in
which they transplanted a baboon heart into an infant who died 20 days
An estimated 600 to 1,400 children a year are born in the United
States with hypoplastic left heart syndrome, and doctors say that when
it is diagnosed in a fetus, many couples end the pregnancy. Many
cases, but not all, are brought on by a narrowed aortic valve.
Jack's heart repair, performed through a needle inserted in his
mother's abdomen, may offer hope of preventing at least some cases of
the syndrome. The operation may also encourage doctors to consider
whether other heart problems might be repaired in fetuses. Even though
doctors have been performing fetal surgery since the 1980's, most
fetal heart surgery is considered too risky and difficult.
The success here, Dr. Perry said, ''has the potential to open up the
Dr. Audrey Marshall, another of Jack's cardiologists, said, ''We think
that with a lot of congenital heart disease, some insult or injury
occurs early in development, and the sooner you correct it, the more
normal these kids can become.''
Doctors caution, though, that fetal procedures must be done only for
conditions that would be fatal or severely disabling, because
operating exposes both mother and fetus to all the usual hazards of
surgery and anesthesia, plus the risk of early labor and the physical
and developmental problems of prematurity.
Jack's story began last summer, when ultrasound scans at about 20
weeks of pregnancy showed that his aortic valve was severely narrowed
and his left ventricle barely working. Doctors felt sure he would have
hypoplastic left heart syndrome.
To his parents, Jennifer and Henry G., who spoke on condition that
their last name not be used, the options seemed bleak. They could end
the pregnancy. They could have the baby, decline surgery and let him
die. Or they could put him through three heart operations.
The couple, college-educated professionals in their 30's, sought help
at Children's Hospital.
There, Dr. Wayne Tworetzky, a cardiologist, described a fourth option,
what he called ''the science fiction procedure.'' He said the
ventricle could not pump blood past the pinched valve. If the valve
could be opened, the ventricle might be able to grow and function
normally. But the procedure would have to be done soon, before the
damage was irreversible.
The approach was science fiction because no one in the United States
had ever made it work. From 1989 to 1997, only 2 of 12 babies survived
attempts at the procedure, according to an article in The American
Journal of Cardiology in May 2000. The operations were done at six
medical centers in England, Germany, Brazil and the United States. In
the case of one survivor, the technique had failed completely, and the
baby required surgery after birth. In the other survivor, the valve
closed up again and had to be reopened several times after the child
was born. Nor was it clear whether hypoplastic left heart syndrome
would have developed without the procedure.
The team at Children's had also tried the technique in 2000, but it
was unable to get the needle into the fetus's heart.
This time the fetus was younger, and Dr. Tworetzky and his colleagues
hoped he might have a ventricle that was less scarred and easier to
Mr. and Mrs. G. decided in favor of science fiction. If it failed,
they would accept the three operations.
Opening a narrowed heart valve may seem like a simple idea, but the
task itself becomes incredibly difficult when the patient is a 23-week
fetus whose heart, a moving target, is the size of a grape. There are
no standard instruments for a procedure on such a tiny heart.
On the morning of Sept. 13, a dozen doctors, nurses and technicians
gathered in an operating room at Brigham and Women's Hospital. Mother
and fetus were anesthetized, and Dr. Louise Wilkins-Haug, an
obstetrician, carefully kneaded Mrs. G.'s abdomen and rolled the fetus
over to give the doctors better access to his heart. When the fetus
was in the right position, Dr. Rusty Jennings, a fetal surgeon, held
him firmly in place. The positioning, guided by ultrasound, was a
crucial step, and it took several hours.
Since obstetricians, who routinely perform amniocentesis, have the
most experience inserting needles into the uterus, it would be Dr.
Wilkins-Haug's job to insert a long needle into the fetus's left
ventricle. She would be guided by ultrasound images on a monitor.
The needle had to be perfectly angled toward the aortic valve -- a
spot about an eighth of an inch in diameter -- and it had to avoid
piercing coronary arteries or parts of the heart that might touch off
disruptions in heart rhythm. Dr. Wilkins-Haug had only one shot. It
would not be safe to jab the heart repeatedly.
With her first thrust of the needle, she passed through the mother's
abdomen and the uterine wall, stopping just outside the fetus's skin.
Studying the monitor, she realized her angle was slightly off, and
corrected it. She pushed the needle into the ventricle. Its position
was perfect, and she held it tightly in place.
Now it was time for Dr. Perry and Dr. Marshall to step in. Watching
the monitor, they passed a threadlike wire through the center of the
needle held by Dr. Wilkins-Haug, into the ventricle and through the
tiny opening of the aortic valve. With the wire in place, they slid a
catheter over it, carrying the same kind of balloon used to dilate
blocked arteries in adults. They inflated the balloon to about an
eighth of an inch, and passed it back and forth several times. Then
they pulled out.
Blood flow through the valve began to improve almost immediately. The
work had taken 20 minutes.
''I remember coming through the anesthesia and being aware of this
general happy chatter around me,'' Mrs. G. said. ''Someone, I think
Dr. Marshall, put a hand on my shoulder and said: 'We did it. We
dilated the valve.' ''
Eleven weeks later, doctors decided to induce labor so that they could
widen the valve again.
Even though he was born six weeks early, Jack emerged ''kicking and
screaming,'' his mother said, weighing 5 pounds 8 ounces and breathing
on his own. His valve did not need more widening.
Jack's outlook is good, although the valve remains narrower than
average. As he grows, Jack may need procedures to widen it, and
someday it may need to be replaced. But what counts more is that Jack
has two ventricles, not one.
''Basically, he'll be a normal little boy with absolutely no
restrictions,'' his mother said. ''He can do anything, play any sports
he wants to.''
Jack's doctors are well aware that medical victories cannot be
declared on the basis of one patient.
''The next 10 cases could be unsuccessful, of course,'' Dr. Tworetzky
said. Nonetheless, he said, ''We showed it can be done.''
Experts at the University of California at San Francisco, a leading
fetal surgery center, received the news about Jack with caution and
enthusiasm. Dr. Michael Harrison, director of the fetal treatment
program and widely regarded as the father of fetal surgery, said: ''I
think it's fabulous. It's the right thinking, and the right way to get
But, he added, ''Single cases can never prove a concept.''
At home last Wednesday night, peering out elfishly from beneath the
pointy hood of his blue sweater, Jack sucked down a bottle of formula
and dozed off, snuggled up on his mother's chest. Jack's 2-year-old
sister, up too late, burst into tears over a missing book and was
swept off to bed. Visitors fussed over Jack. His mother looked down at
him and said, ''We were handed a miracle.'' Jack, oblivious, smiled in
Drawing (Illustrations by Emily Flynn McIntosh)(pg. A17) Chart:
''Fetal Heart Repair'' A fetus suffering from a severe narrowing of a
heart valve, which can lead to hypoplastic left heart syndrome -- a
disorder where the left ventricle does not fully develop -- had a
procedure to correct the problem. 1. A hollow needle is inserted
through the mother's abdomen and into the baby's heart. 2. A guide
wire is threaded through the hollow needle, followed by a catheter
carrying a balloon that will dilate the aorta and aortic valve, which
are narrowed in this syndrome. (Diagram) DILATING BALLOON -- Opens up
narrow aortic valve. ULTRASOUND TRANSDUCER -- Provides an image of the
fetus on a monitor, which doctors use to guide the procedure
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