- Fighting the flab when it's at the stage of morbid obesity
is no picnic. A new device may soon ease the battle by sending electrical
pulses to the patient's stomach, tricking him into thinking he is full.
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- The Transcend Implantable Gastric Stimulator features
a pocket watch-sized gizmo implanted just below the rib cage. "It's
an electrical pulse generator similar to a heart pacemaker with wiring,
called the lead, that's attached to the muscle wall of the stomach,"
said Dr. Scott Shikora, surgeon and associate director of the Obesity Consult
Center at Tufts-New England Medical Center.
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- Shikora, who has implanted 27 of the devices as part
of a clinical trial, said the system offers a safer alternative to current
surgeries that often require the patient's insides to be rearranged --
literally. Current fixes use staples or a band to divide the stomach, creating
a much smaller chamber in which the food is digested. Anything eaten beyond
the capacity of the new, smaller tummy is often vomited back up.
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- Though effective, the surgery comes with a number of
risks. The National Institutes of Health estimates between 10 percent and
20 percent of patients who have weight-loss surgery require follow-up operations
to correct complications, and 1 percent die.
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- The stimulator, however, doesn't require any internal
rejiggering. "The stimulator doesnít change the stomach at
all but still gives the feeling of satiety," Shikora said. "There
haven't even been any significant minor complications with the procedure,"
he added.
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- It takes less than an hour to implant the 42-gram titanium
stimulator, and the patient can go home a few hours after the operation.
A gastric bypass takes around three hours, and the patient has to remain
in the hospital for up to four days.
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- "We use laparoscopy to position the wires and attach
them," Shikora said. In laparoscopy, the surgeon makes several small
incisions through which the surgical instruments and a camera are passed.
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- Once in place, the surgeon gives the device a test run
to make sure all is in working order. The system is initially inoperative,
to allow the stomach wall to heal. Fourteen days after implantation, the
device is switched on using an external programmer.
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- "The programmer works in essentially the same way
as the heart pacemakers do," Shikora said. "It's essentially
a laptop and a radio-frequency wand. You hold the wand over the device
and it communicates with it using radio waves." The programmer allows
the doctor to set the intensity, frequency and pattern of the electrical
pulses.
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- "You have a wide variety of patterns it can be programmed
to do," said Steve Adler, vice president of Transneuronix, the device's
Arlington, New Jersey, manufacturer.
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- The patient is unaware of all this electrical activity
going on in his tummy. "The patient should feel a change in their
satiety and appetite but should not feel electrical shocks," Adler
said.
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- How these electrical pulses actually work is currently
not known. "It could be that it stimulates nerves to the brain, or
it might inhibit certain hormones that affect appetite. It may be that
it affects the muscular tone of the stomach and so makes you think you
are full," Shikora said.
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- So far the device has been implanted in around 450 patients
worldwide -- most of these in Europe, where the device is already available
for sale. Its success rate, however, has been hit-or-miss.
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- "There has been a lot of variability," Shikora
said. "Some patients have responded almost miraculously, losing 40
percent of their excess weight. Others have had no response."
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- The drawback is that, while the system works well to
give the sensation of fullness, there are no repercussions if the patient
chooses to ignore this feeling.
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- "There is no backup system in place with the pacemaker.
If you are eating out of stress -- which many of our patients do -- then
you are eating even if you are not hungry, and with the pacemaker you can
eat right through really easily. You can't do this with the lap band or
gastric bypass because you will throw up," said Dr. Neil Hutcher,
weight-management surgeon in Richmond, Virginia, and secretary of the American
Society for Bariatric Surgery.
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- The upcoming two-year trial hopes to overcome this problem
by using a screening test to weed out the people less likely to respond
to the treatment. "We are looking for people who are not binge eaters,"
Kushner said.
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- If the trial proves effective, the stimulator could step
in where other, more-invasive treatments cannot be employed due to medical
complications such as heart conditions or previous abdominal surgery.
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- The procedure has the added advantage of cost. A gastric
bypass costs up to $40,000, the lap band up to $30,000. The stimulator
can be found in Europe for as low as 5,000 euros (around $6,000).
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- "We are hoping FDA approval will happen after this
next trial," Shikora said.
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