SAN FRANCISCO (AP) — Have a heart problem? If it's
fixable, there's a good chance it can be done without surgery, using
tiny tools and devices that are pushed through tubes into blood vessels.
Heart care is in the midst of a transformation. Many problems that
once required sawing through the breastbone and opening up the chest for
open heart surgery now can be treated with a nip, twist or patch
through a tube.
These minimal procedures used to be done just to unclog arteries and
correct less common heart rhythm problems. Now some patients are getting
such repairs for valves, irregular heartbeats, holes in the heart and
other defects — without major surgery. Doctors even are testing ways to
treat high blood pressure with some of these new approaches.
All rely on catheters — hollow tubes that let doctors burn away and
reshape heart tissue or correct defects through small holes in blood
vessels.
"This is the replacement for the surgeon's knife. Instead of opening
the chest, we're able to put catheters in through the leg, sometimes
through the arm," said Dr. Spencer King of St. Joseph's Heart and
Vascular Institute in Atlanta. He is former president of the American
College of Cardiology. Its conference earlier this month featured
research on these novel devices.
"Many patients after having this kind of procedure in a day or two
can go home" rather than staying in the hospital while a big wound
heals, he said. It may lead to cheaper treatment, although the initial
cost of the novel devices often offsets the savings from shorter
hospital stays.
Not everyone can have catheter treatment, and some promising devices
have hit snags in testing. Others on the market now are so new that it
will take several years to see if their results last as long as the
benefits from surgery do.
But already, these procedures have allowed many people too old or
frail for an operation to get help for problems that otherwise would
likely kill them.
"You can do these on 90-year-old patients," King said.
These methods also offer an option for people who cannot tolerate
long-term use of blood thinners or other drugs to manage their
conditions, or who don't get enough help from these medicines and are
getting worse.
"It's opened up a whole new field," said Dr. Hadley Wilson,
cardiology chief at Carolinas HealthCare System in Charlotte. "We can
hopefully treat more patients more definitively, with better results."
For patients, this is crucial: Make sure you are evaluated by a
"heart team" that includes a surgeon as well as other specialists who do
less invasive treatments. Many patients now get whatever treatment is
offered by whatever specialist they are sent to, and those specialists
sometimes are rivals.
"We want to get away from that" and do whatever is
best for the patient, said Dr. Timothy Gardner, a surgeon at Christiana
Care Health System in Newark, Del., and an American Heart Association
spokesman. "There shouldn't be a rivalry in the field."
Here are some common problems and newer treatments for them:
HEART VALVES
Millions of people have leaky heart valves. Each year, more than
100,000 people in the United States alone have surgery for them. A
common one is the aortic valve, the heart's main gate. It can stiffen
and narrow, making the heart strain to push blood through it. Without a
valve replacement operation, half of these patients die within two
years, yet many are too weak to have one.
"Essentially, this was a death sentence," said Dr. John Harold, a Los
Angeles heart specialist who is president of the College of Cardiology.
That changed just over a year ago, when Edwards Lifesciences Corp.
won approval to sell an artificial aortic valve flexible and small
enough to fit into a catheter and wedged inside the bad one. At first it
was just for inoperable patients. Last fall, use was expanded to
include people able to have surgery but at high risk of complications.
Gary Verwer, 76, of Napa, Calif., had a bypass operation in 1988 that
made surgery too risky when he later developed trouble with his aortic
valve.
"It was getting worse every day. I couldn't walk from my bed to my
bathroom without having to sit down and rest," he said. After getting a
new valve through a catheter last April at Stanford University,
"everything changed; it was almost immediate," he said. "Now I can walk
almost three miles a day and enjoy it. I'm not tired at all."
"The chest cracking part is not the most fun," he said of his earlier
bypass surgery. "It was a great relief not to have to go through that
recovery again."
Catheter-based treatments for other valves also are in testing. One
for the mitral valve — Abbott Laboratories' MitraClip — had a mixed
review by federal Food and Drug Administration advisers this week;
whether it will win FDA approval is unclear. It is already sold in
Europe.
HEART RHYTHM PROBLEMS
Catheters can contain tools to vaporize or "ablate" bits of heart
tissue that cause abnormal signals that control the heartbeat. This used
to be done only for some serious or relatively rare problems, or
surgically if a patient was having an operation for another heart issue.
Now catheter ablation is being used for the most common rhythm
problem — atrial fibrillation, which plagues about 3 million Americans
and 15 million people worldwide. The upper chambers of the heart quiver
or beat too fast or too slow. That lets blood pool in a small pouch off
one of these chambers. Clots can form in the pouch and travel to the
brain, causing a stroke.
Ablation addresses the underlying rhythm problem. To address the
stroke risk from pooled blood, several novel devices aim to plug or seal
off the pouch. Only one has approval in the U.S. now — SentreHeart
Inc.'s Lariat, a tiny lasso to cinch the pouch shut. It uses two
catheters that act like chopsticks. One goes through a blood vessel and
into the pouch to help guide placement of the device, which is contained
in a second catheter poked under the ribs to the outside of the heart. A
loop is released to circle the top of the pouch where it meets the
heart, sealing off the pouch.
A different kind of device — Boston Scientific Corp.'s Watchman — is
sold in Europe and parts of Asia, but is pending before the FDA in the
U.S. It's like a tiny umbrella pushed through a vein and then opened
inside the heart to plug the troublesome pouch. Early results from a
pivotal study released by the company suggested it would miss a key
goal, making its future in the U.S. uncertain.
HEART DEFECTS
Some people have a hole in a heart wall called an atrial septal
defect that causes abnormal blood flow. St. Jude Medical Inc.'s
Amplatzer is a fabric-mesh patch threaded through catheters to plug the
hole.
The patch is also being tested for a more common defect — PFO, a hole
that results when the heart wall doesn't seal the way it should after
birth. This can raise the risk of stroke. In two new studies, the device
did not meet the main goal of lowering the risk of repeat strokes in
people who had already suffered one, but some doctors were encouraged by
other results.
CLOGGED ARTERIES
The original catheter-based treatment — balloon angioplasty — is
still used hundreds of thousands of times each year in the U.S. alone. A
Japanese company, Terumo Corp., is one of the leaders of a new way to
do it that is easier on patients — through a catheter in the arm rather
than the groin.
Newer stents that prop arteries open and then dissolve over time,
aimed at reducing the risk of blood clots, also are in late-stage
testing.
HIGH BLOOD PRESSURE
About 75 million Americans and 1 billion people worldwide have high
blood pressure, a major risk factor for heart attacks. Researchers are
testing a possible long-term fix for dangerously high pressure that
can't be controlled with multiple medications.
It uses a catheter and radio waves to zap nerves, located near the
kidneys, which fuel high blood pressure. At least one device is approved
in Europe and several companies are testing devices in the United
States.
"We're very excited about this,"
said Harold, the cardiology college's president. It offers hope to
"essentially cure high blood pressure."
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