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If you
have been diagnosed with a condition called aortic stenosis –
narrowing of the aortic valve in your heart. There are several
different treatment options available to a patient with this
condition depending upon the circumstances.
These options include:
1. Treatment with medication
2. Open-heart surgery to replace the aortic valve
with a new one
3. A procedure called balloon aortic valvuloplasty
which is intended to temporarily stretch the aortic valve open with
a balloon
4. A procedure called Transcatheter Aortic Valve
Replacement (TAVR) which is intended to implant a new artificial
valve in your heart without using open heart surgery
Each of these options has risks and benefits which
will be explained.
What is aortic stenosis?
Your heart contains four valves. These valves make
sure that the blood flows in the right direction out of the heart.
The aortic (outlet) valve is on the left side of the heart and opens
when blood is pumped from the heart to the rest of the body. Aortic
stenosis is the term used when the aortic valve is narrowed,
interfering with flow of blood out of the heart. Once you develop
aortic stenosis with time it usually worsens.
The main causes of aortic stenosis include:
• Being born with this abnormality (congenital)
• Rheumatic valve disease
• "Wear and tear "of the valve.
Aortic stenosis places an extra strain on the
heart and may affect the circulation of the blood. This can result
in breathlessness and fluid retention – which can cause swollen
ankles and legs. You may also suffer from chest pain, dizziness and
fainting.
Treatment of your aortic stenosis with
medications: No medications can reverse aortic valve stenosis.
However, once you develop symptoms from aortic stenosis, your doctor
may prescribe certain medications to help your heart. These
medications include, among others, diuretics (water pills),
medications to lower your blood pressure, medications to lower your
cholesterol and medications to control heart rhythm disturbances
associated with aortic valve stenosis. No medication has been proven
to prolong your life once you develop symptoms from aortic stenosis.
In general, after a patient has developed symptoms from aortic
stenosis, average survival is two to three years if the aortic valve
remains narrowed.
Treatment of your aortic stenosis with open heart surgery:
In patients with symptomatic aortic stenosis, open
heart surgery to repair or replace your narrowed aortic valve is
considered conventional (standard) treatment. In most patients, open
heart surgery for aortic stenosis has been shown to relieve symptoms
and to prolong the patient’s life.
Due to your overall medical condition, however,
your cardiologist and cardiac surgeon have determined that you are
not a candidate for standard open-heart surgery. Specifically, your
cardiologist and cardiac surgeon believe that you have at least a
50% (1 in 2) risk of death or serious complications if you were to
have your valve replaced through a conventional open-heart
procedure. Accordingly, conventional surgery is not suitable for you
because of this level of risk.
Treatment of your aortic stenosis with balloon aortic
valvuloplasty:
In patients with severe aortic stenosis who are
not considered candidates for standard open heart surgery, a
procedure called balloon aortic valvuloplasty may be performed to
improve your symptoms. This procedure involves stretching the
narrowed valve with a balloon inserted into the heart using a
catheter (thin tube). This procedure is associated with a 3-5% risk
of death, has not been shown to prolong your life, and results in
only a temporary improvement in symptoms for a period of three to
six months.
Treatment of your aortic stenosis with Transcatheter Aortic Valve
Replacement (TAVR)
In November 2011, the United States Food and
Drug Administration approved the use of new procedure called
Transcatheter Aortic Valve Replacement (TAVR) for treating patients
with aortic stenosis who are not considered candidates for standard
open heart surgery. In this procedure, a new valve is inserted via a
catheter (a thin tube) into the heart. The new valve is made up of a
stent (a stainless steel tube) and biological tissue taken from
cows. The TAVR valve is inserted into your heart from your femoral
artery, the main blood vessel in your groin. Your cardiac surgeon
will expose the femoral artery by making a small incision in your
groin. The TAVR procedure is carried out under general anesthesia.
After a thorough review of your medical condition, your cardiologist
and cardiac surgeon have determined that you are a potential
candidate for the TAVR procedure. The possible risks and benefits of
the TAVR procedure are discussed below.
How will it be determined if I am a candidate for
the TAVR procedure?
All patients must undergo a series of screening
tests to determine if they are eligible for the TAVR procedure.
These tests may include but are not limited to:
• A routine physical examination
• An ECG (a recording of your heart rhythm)
• Routine blood tests
• A transthoracic echocardiogram- an ultrasound of
your heart.
• A transesophageal echocardiogram (TEE) - This
procedure involves temporarily inserting a small ultrasound probe
which obtains pictures of your heart from the inside of your
esophagus (the tube that leads from your mouth to your stomach).
• A cardiac catheterization. This procedure
involves inserting catheters into your femoral artery and femoral
vein to directly measure the narrowing of your aortic valve and to
inject X-ray dye into your heart arteries to see if you have any
coronary blockages.
• Computerized tomography (CT scan) of your chest,
abdomen, and pelvis. This usually involves an injection of X-ray dye
into an intravenous placed in your arm.
Some patients may require additional screening
tests which include:
• Lung function tests – which involve breathing
into a tube to measure your lung capacity.
• An ultrasound of the arteries of your neck.
What happens during the TAVR procedure?
Immediately before the procedure in the
preoperative area, a cannula (a small tube) will be inserted into an
artery in your wrist to allow us to closely monitor your blood
pressure. You will have a second cannula inserted into a vein in
your neck to allow us to monitor you and to give you medication
and/or fluids easily. You will also have a urinary catheter inserted
into your bladder so that you can pass urine freely into a bag.
The TAVR procedure will be performed in the
operating room under general anesthesia by a team of physicians
including cardiac surgeons, cardiologists and an anesthesiologist.
Special X-rays using a contrast dye and transesophageal
echocardiography (a small ultrasound probe which obtains pictures of
your heart from the inside of your esophagus) are used to guide the
new valve into the correct position. A surgeon will operate on the
top of your leg to expose your femoral artery and insert a catheter
into the exposed artery. The catheter has a special balloon on the
end which is then inflated to stretch open your narrowed aortic
valve. Next, the new TAVR valve will be carefully compressed and
mounted onto a second balloon delivery catheter, using a specially
designed device. The mounted valve will be inserted through the
femoral artery into your narrowed aortic valve where the balloon is
used to expand and implant the new valve after it is properly
positioned. The balloon is then deflated and removed and the surgeon
repairs the puncture site in your groin. We will spee d
your
heart rate up to 200 beats per minute using a temporary pacing wire.
This wire is put in through a vein in your groin and passed through
the vein to your heart. An electrical impulse is then passed through
the wire in order to speed up your heart rate for only a few
seconds. This reduces the blood pressure and motion of the heart,
which makes the TAVR valve positioning procedure easier. When the
new valve is in place, the pacing is stopped and your heart rate
will return to normal. The pacing wire is then removed immediately
or a later time, depending on the decision of the surgeon. The whole
procedure takes 2-3 hours.
What happens after the TAVR procedure?
You will go to the Cardiovascular Surgical
Intensive Care Unit (CVICU) so that you can be closely monitored.
You will have your breathing tube removed first and then the tubes
in your neck, wrist and chest as soon as you are medically stable.
You will stay in the intensive care unit area until you are ready to
be moved to regular hospital bed in the step-down unit. After the
procedure, your doctor will ask you to take Aspirin and Clopidogrel
(a blood thinning tablet).
Your cardiologist or cardiac surgeon will tell you
for how long you will need to take the tablets; it may be for the
rest of your life.
You will have the following tests after the
procedure while you are still in the hospital:
• A chest X-ray
• A urine analysis
• Routine blood tests
• An electrocardiogram (ECG)
• A transthoracic echocardiogram.
How will I be followed up?
We will ask you to come back to the hospital four
to six weeks later for a physical examination. You may need further
tests; for example, another echocardiogram, ECG or chest X-ray.
Assuming you are doing well, we will then see you
only once every 6-12 months to keep an eye on your condition.
What are the potential benefits of the TAVR
procedure?
Treatment with the new TAVR valve may give you
both short and long term relief of your symptoms. It may give you
normal aortic valve function and improve your overall heart
function. This could potentially increase your life expectancy and
your quality of life. What are the potential risks of
the TAVR procedure? It is important to remember
that aortic stenosis is a serious condition. Without treatment,
there is a high risk of progressive symptoms and death. Your
cardiologist and cardiac surgeon will carefully consider the risks
and benefits and then talk about them with you.
The risks associated with transcatheter aortic
valve implantation include:
Major risks
• Death
• Stroke
• Bleeding or damage to the groin artery, needing
blood transfusion or surgery
• Heart attack
• Kidney failure
If you already have kidney failure, the dye that
is used during the X-rays may cause additional kidney damage and
require dialysis. To prevent this from happening, your doctor will
continually monitor the amount of dye you are given.
• Emergent cardiac surgery
In extreme cases where placement of the TAVR valve
is suboptimal or where the procedure results in worsening of your
heart function, it may be necessary to carry out immediate emergent
open-heart surgery to replace the aortic valve. The surgical team
and all the emergency equipment will be immediately available. The
cardiopulmonary (heart and lung) bypass machine will be used to take
over the circulation of your blood during the operation. The risks
of cardiopulmonary bypass include a stroke and getting an infection
in the groin incision.
Serious risks
• An allergic reaction to the X-ray dye
• A reaction to the anesthesia
• An infection including:
1. Endocarditis (an inflammation of the heart)
2. Septicemia (an infection in the blood)
3. Infection of the incisions
• A pericardial effusion – bleeding into the sack
around the heart.
• Esophageal perforation, bleeding or infection.
Less serious risks
• An arrhythmia – abnormal heart beat
• Bruising around the wound site
• A non-emergency repeat operation
• A paravalvular leak – a leakage of blood around
the device
What are the alternatives to TAVR valve
implantation?
As discussed above, the alternative treatment
options for patients with aortic stenosis are:
• Surgical aortic valve replacement (conventional
open-chest surgery to replace your aortic valve with a new one)
• Balloon aortic valvuloplasty
• Treatment with medication
The preferred treatment for severe aortic stenosis
is conventional aortic valve replacement, but at the present time,
you are considered too high risk, and thus not a candidate for this
type of surgery. Balloon aortic valvuloplasty is associated with
3-5% risk of death, may result in a three to six month improvement
in symptoms, and has not been shown to prolong your life. Medical
therapy is associated with a two to three year lifespan once a
patient has developed symptoms from aortic stenosis.
Questions about the TAVR procedure may be
answered by calling:
• Orlando Heart Center: 407-650-1300
CVICU – Cardiovascular Intensive Care Unit •
ECG - Electrocardiogram
TAVR – Transcatheter Aortic Valve Replacement
TEE – Transesophageal echocardiogram
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