Surgery
If medications are not effective in controlling your symptoms of
mitral valve stenosis or if your doctor determines
that you need more aggressive treatment, you may need surgery to repair or
replace your mitral valve. While valve surgery is common and usually
successful, a degree of risk is associated with this invasive procedure. There
are generally three options: a balloon valvotomy, a closed (or open)
commissurotomy surgery, or valve replacement surgery.
Valve repair (balloon valvotomy)
Balloon valvotomy (percutaneous mitral balloon
valvotomy) is the method of choice for treating mitral valve stenosis in select
patients. A thin flexible tube (catheter) is inserted through an artery in the
groin or arm and threaded into the heart. When the tube reaches the narrowed
mitral valve, a balloon located on the tip of the catheter is quickly inflated.
The balloon, pressing against the narrowed mitral valve leaflets, separates and
stretches the valve opening and allows more blood to flow through the heart.
This procedure does not require open-heart surgery, which makes recovery
easier.
A balloon valvotomy is usually recommended if you have symptoms
and moderate to severe stenosis.2
Your doctor will measure your
pressure gradient and valve size to determine the
severity of the stenosis. A normal mitral valve has an opening between 4 and 5
cm2.
A balloon valvotomy may also be used to treat people with mitral
valve stenosis who do not yet have symptoms (asymptomatic) if they
have:4
- An increased risk of dangerous blood clots
(thromboembolism). This includes people with an irregular heart rhythm called
atrial fibrillation, as well as those who have had a
blood clot before.
- High blood pressure in the lungs (pulmonary
hypertension).
- A need for surgery outside of the heart as
well.
- Plans to become pregnant or are pregnant.
- Mitral
valves that are still in fairly good condition.
People with signs of blood clots in the left atrium, widespread
calcification of the mitral valve structures, or moderate to severe
mitral valve regurgitation are not considered good
candidates for a balloon valvotomy.2
The mitral valve may narrow again (restenosis) after 10
to 20 years.
Valve surgery (open heart)
Depending on the amount of damage to your mitral valve, your
doctor may recommend open-heart surgery to repair or replace your mitral valve.
If the valve is damaged beyond repair, it will need to be replaced.
During open-heart surgery, your heartbeat is stopped, and you are
placed on a heart-lung machine to deliver blood to your body. The heart-lung
machine temporarily serves in place of your heart and lungs by mixing oxygen
with the blood, removing carbon dioxide from the blood, and pumping the blood
throughout your body.
Valve repair
In open commissurotomy, a surgeon removes calcium deposits and
other scar tissue from the mitral valve leaflets, which opens the valve. This
procedure is used for people who have severe narrowing of the valve and are not
good candidates for balloon valvotomy.
Valve replacement
The damaged heart valve is removed and replaced with a new valve.
This is generally done when your mitral valve is damaged beyond repair. With
improved technology, mitral valve replacement is becoming an important surgical
option. Some doctors believe that replacement mitral valves are now more
durable. In addition, more of the original mitral valve and its support
structure (such as the chordae tendineae) are preserved during valve
replacement. The long-term results of surgery are generally better when more of
the original mitral valve structure is preserved.5
If you have an
artificial valve, getting an infection in your heart
(endocarditis) could be very dangerous for you. To
prevent an infection, you may need to take
antibiotics before you have certain
dental or surgical procedures.
Replacement heart valves
There are two types of replacement valves:
- A mechanical heart
valve is made from plastic or metal. It is more likely to cause blood
clots in the heart that can travel to the brain and cause a
stroke. Because of this danger, people who have a
mechanical heart valve must take anticoagulant medication for the rest of their
lives. This medication prevents blood clots from forming.
- A bioprosthetic heart valve is made
from human or animal (usually pig) tissue. In most people, it has the advantage
of not requiring medication to prevent blood clots. However, bioprosthetic
valves are not as sturdy as the mechanical valves. They usually need to be
surgically replaced after about 10 years. Bioprosthetic valves are usually
inserted in people older than 70.
Most people who have mitral valve replacement surgery will
receive a mechanical heart valve. Even if a bioprosthetic tissue valve is used,
you will need to take anticoagulants if you also have other heart conditions
such as abnormal heartbeat (arrhythmia) or a dilated left atrium;
both of these conditions are risk factors for stroke.