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Facts
About Heart and Heart-Lung Transplants
In
the three decades since the performance of the first human heart
transplant in December 1967, the procedure has changed from an experimental
operation to an established treatment for advanced heart disease.
Approximately 2,300 heart transplants are performed each year in
the United States.
In
1981, combined heart and lung transplants began to be used to treat
patients with conditions that severely damage both these organs.
As of 1995, about 500 people in the United States and 2,000 worldwide
have received heart-lung transplants.
There
have been two main barriers to increasing the number of successful
operations. In 1983, the first barrier to successful transplantations--rejection
of the donor organ by the patient--was overcome. The drug cyclosporine
was introduced to suppress rejection of a donor heart or heart-lung
by the patient's body. Cyclosporine and other medications to control
rejection have significantly improved the survival of transplant
patients. About 80 percent of heart transplant patients survive
1 year or more. About 60 percent of heart-lung transplants live
at least 1 year after surgery. Research is under way to develop
even better ways to control transplant rejection and improve survival.
Organ
availability is the second barrier to increasing the number of successful
transplantations. Hospitals and organizations nationwide are trying
to increase public awareness of this problem and improve organ distribution.
A transplant
is the replacement of a patient's diseased heart or heart and lungs
with a normal organ(s) from someone--called a donor--who has died.
The donor's organ(s) is completely removed and quickly transported
to the patient, who may be located across the country. Organs are
cooled and kept in a special solution while being taken to the patient.
During
the operation, the patient is placed on a heart-lung machine. This
machine allows surgeons to bypass the blood flow to the heart and
lungs. The machine pumps the blood throughout the rest of the body,
removing carbon dioxide (a waste product) and replacing it with
oxygen needed by body tissues. Doctors remove the patient's heart
except for the back walls of the atria, the heart's upper chambers.
The backs of the atria on the new heart are opened and the heart
is sewn into place. A similar process is followed in heart-lung
transplants, except doctors remove the heart and lungs as a unit
from the donor; the new lungs are attached first, followed by the
heart.
Surgeons
then connect the blood vessels and allow blood to flow through the
heart and lungs. As the heart warms up, it begins beating. Sometimes,
surgeons must start the heart with an electrical shock. Surgeons
check all the connected blood vessels and heart chambers for leaks
before removing the patient from the heart-lung machine.
Patients
are usually up and around a few days after surgery, and if there
are no signs of the body immediately rejecting the organ(s), patients
are allowed to go home within 2 weeks.
A transplant
is considered when the heart is failing and does not respond to
all other therapies, but health is otherwise good. The leading reasons
why people receive heart transplants are:
- Cardiomyopathy--a
weakening of the heart muscle.
- Severe
coronary artery disease--in which the heart's blood vessels become
blocked and the heart muscle is damaged.
- Birth
defects of the heart.
Heart-lung
transplants are performed on patients who will die from end-stage
lung disease that also involves the heart. Alternative therapies
for these patients have been tried or considered. Leading reasons
people receive heart-lung transplants are:
- Severe
pulmonary hypertension--a large increase in blood pressure in
the vessels of the lungs that limits blood flow and delivery of
oxygen to the rest of the body.
- A
birth defect of the heart that results in Eisenmenger's complex--another
name for acquired pulmonary hypertension.
Patients
under age 60 are the most likely heart transplant candidates. Patients
under age 45 are generally accepted for heart-lung transplants.
In both cases, patients must be suffering from end-stage disease
and be in good health otherwise. The doctor, patient, and family
must address the following four basic questions to determine whether
a transplant should be considered:
- Have
all other therapies been tried or excluded?
- Is
the patient likely to die without the transplant?
- Is
the person in generally good health other than the heart or heart
and lung disease?
- Can
the patient adhere to the lifestyle changes--including complex
drug treatments and frequent examinations--required after a transplant?
Patients
who do not meet the above considerations or who have additional
problems--other severe diseases, active infections, or severe obesity--are
not good candidates for a transplant.
Donors
are individuals who are brain dead, meaning that the brain shows
no signs of life while the person's body is being kept alive by
a machine. Donors have often died as a result of an automobile accident,
a stroke, a gunshot wound, suicide, or a severe head injury. Most
hearts come from those who die before age 45. Donor organs are located
through the United Network for Organ Sharing (UNOS).
Not
enough organs are available for transplant. At any given time, almost
3,500 to 4,000 patients are waiting for a heart or heart-lung transplant.
A patient may wait months for a transplant. More than 25 percent
do not live long enough. Yet, only a fraction of those who could
donate organs actually do.
After
a heart or heart-lung transplant, patients must take several medications.
The most important are those to keep the body from rejecting the
transplant. These medications, which must be taken for life, can
cause significant side effects, including hypertension, fluid retention,
tremors, excessive hair growth, and possible kidney damage. To combat
these problems, additional drugs are often prescribed.
A transplanted
heart functions differently from the old one. Because the nerves
leading to the heart are cut during the operation, the transplanted
heart beats faster (about 100 to 110 beats per minute) than the
normal heart (70 beats per minute). The new heart also responds
more slowly to exercise and doesn't increase its rate as quickly
as before.
A patient's
prognosis depends on many factors, including age, general health,
and response to the transplant. Recent figures show that 73 percent
of heart transplant patients live at least 3 years after surgery.
Nearly 85 percent of patients return to work or other activities
they like. Many patients enjoy swimming, cycling, running, or other
sports.
As
noted, 60 percent of patients who receive combined heart-lung transplants
survive at least 1 year. Fifty percent live at least 3 years.
The
most common causes of death following a transplant are infection
or rejection of the heart. Patients on drugs to prevent transplant
rejection are at risk for developing kidney damage, high blood pressure,
osteoporosis (a severe thinning of the bones, which can cause fractures),
and lymphoma (a type of cancer that affects cells of the immune
system).
Coronary
artery disease (atherosclerosis) is a problem that develops in almost
half the patients who receive transplants. Normally, patients with
this disease experience chest pain and/or other symptoms when their
hearts are under stress. This is called angina and is an early warning
sign of a blocked heart artery. However, transplant patients may
have no early pain symptoms of a blockage building up because they
have no sensations in their new hearts.
Thirty
to fifty percent of patients who receive a heart-lung transplant
develop bronchiolitis obliterans, in which there are obstructive
changes in the airways of the lungs.
The
body's immune system protects the body from infection. Cells of
the immune system move throughout the body, checking for anything
that looks foreign or different from the body's own cells. Immune
cells recognize the transplanted organ(s) as different from the
rest of the body and attempt to destroy it--this is called rejection.
If left alone, the immune system would damage the cells of a new
heart and eventually destroy it. In a heart-lung transplant, immune
cells may also destroy healthy lung tissue.
To
prevent rejection, patients receive immunosuppressants, drugs that
suppress the immune system so that the new organ(s) is not damaged.
Because rejection can occur anytime after a transplant, immunosuppressive
drugs are given to patients the day before their transplant and
thereafter for the rest of their lives. To avoid complications,
patients must strictly adhere to their drug regimen. The three main
drugs now being used are cyclosporine, azathioprine, and prednisone.
Researchers are working on safer, more effective immunosuppressants
for future testing. Some of the more promising drugs are FK-506
and mycophenolate mofetil.
Doctors
must balance the dose of immunosuppressive drugs so that a patient's
transplanted organ(s) is protected, but his or her immune system
is not completely shut down. Without an active enough immune system,
a patient can easily develop severe infections. For this reason,
medications are also prescribed to fight any infections.
To
carefully monitor transplant patients for signs of heart rejection,
small pieces of the transplanted organ are removed for inspection
under a microscope. Called a biopsy, this procedure involves advancing
a thin tube called a catheter through a vein to the heart. At the
end of the catheter is a bioptome, a tiny instrument used to snip
off a piece of tissue. If the biopsy shows damaged cells, the dose
and kind of immunosuppressive drug may be changed. Biopsies of the
heart muscle are usually performed weekly for the first 3 to 6 weeks
after surgery, then every 3 months for the first year, and then
yearly thereafter.
According
to the UNOS, the estimated first year charges for a heart transplant
is $209,100, and annual followup charges are $15,000. In most cases
these costs are paid by private insurance companies. More than 80
percent of commercial insurers and 97 percent of Blue Cross/Blue
Shield plans offer coverage for heart transplants. Medicaid programs
in 33 states and the District of Columbia also reimburse for transplants.
Heart transplants are covered by Medicare for Medicare-eligible
patients if the operation is performed at an approved center.
Approximately
70 percent of commercial insurance companies and 92 percent of Blue
Cross/Blue Shield plans cover heart-lung transplants. Medicaid coverage
for heart-lung transplants is available in 20 states. According
to the UNOS, estimated first year charges for a heart-lung transplant
is $246,000, and annual followup charges are $18,400.
Hospitals
nationwide are trying to set up a better system for distributing
organs to patients in need. Researchers are looking for easier methods
to monitor rejection to replace the regular biopsies that are needed
now. Work is progressing to make immunosuppressive drugs with fewer
long-term side effects so that coronary artery disease development
and lung destruction may by prevented.
Information
is available 24 hours a day, 7 days a week from the UNOS at 1-800-24-DONOR.
This hotline provides general information on transplants, current
statistics, and listings of transplant centers.
Additional
information is available from the
- Division
of Transplantation
- Health
Resources and Services Administration
- Room
7-29, 5600 Fishers Lane
- Rockville,
MD 20857.
- Telephone:
301-443-7577
-
reference:
from the National Heart, Lung, and Blood Institute
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