Three different procedures are used to treat
mitral valve stenosis:
- Valve replacement surgery
- Balloon
valvotomy (percutaneous balloon valvotomy)
- Open or closed mitral
commissurotomy
Valve replacement and open commissurotomy are major,
open-heart procedures that place considerable stress on your body. But they may
be necessary to prevent potentially debilitating complications associated with
mitral valve stenosis. Balloon valvotomy is a catheter-based procedure and an
alternative to open-heart surgery. While very successful for most people, this
procedure may have to be repeated.
Deciding whether you need
surgery and if so, when, are the major treatment decisions for mitral valve
stenosis. Three factors should be assessed when making this decision: the
severity of your mitral valve stenosis, the possibility that it will get worse,
and the risks of surgery.
Assessing severity and its effect on your heart
The
guiding factors when deciding to have valve surgery are the severity of your
mitral valve stenosis and the effect it is having on your heart. Valve surgery
is usually performed only if the stenosis is serious and in danger of doing
irreparable damage to your heart. In this case, the danger to your heart
outweighs the risks associated with surgery. Fortunately, mitral valve stenosis
typically progresses very slowly (though it tends to accelerate as you age).
You may have as many as 10 years from the time you develop symptoms until your
mitral valve stenosis becomes severe.
Your symptoms and the area
of your mitral valve determine how severe your mitral stenosis is: the smaller
the area, the lower the volume of blood that is able to pass through it, and
hence the more severe your stenosis. The pressure difference between your left
atrium and left ventricle, as well as the blood pressure in your lungs, is also
used to assess severity. Generally, surgery is recommended to repair or replace
the mitral valve when your valve area drops below 1.5
cm2 and you have symptoms that are significantly
interfering with your lifestyle.
Repair or replacement of any kind
is recommended if you do not have symptoms but your mitral valve stenosis is
severe. But other risk factors including age, speed of deterioration, and
overall health are also considered, and these may determine that you need
surgery despite not having any symptoms.
Will my mitral valve stenosis get worse?
Another
important factor is the likelihood that your condition will get worse rapidly
without surgery. If your mitral valve stenosis has been progressing slowly, or
your symptoms are mild, then surgery may not be immediately necessary. But the
presence of other compounding factors, such as pulmonary hypertension (high
blood pressure in your lungs), abnormal heartbeat (arrhythmia),
and
coronary artery disease (CAD), will likely accelerate
the progression of your mitral valve stenosis. In this case, surgery may be
necessary in the near future.
Your doctor will assess the
progression of your mitral valve stenosis by comparing the results of your most
recent
echocardiogram with earlier echocardiogram results. If
you have mild mitral valve stenosis, your doctor will probably perform an
echocardiogram only every 3 or 4 years. But if your echocardiogram comparisons
indicate that your stenosis has become considerably worse since your last
echocardiogram, your doctor may begin to order echocardiograms more frequently.
Risks of surgery
The severity of your mitral valve
stenosis and the likelihood that it will get worse need to be balanced against
the risks of having valve surgery. Specifically, mitral valve replacement has
an operative mortality rate of less than 5%, but this rate can be as high as
10% to 20% for individuals who also have pulmonary hypertension.1
Although most people have successful outcomes, the risk of death and serious
problems during surgery is real. It should be strongly weighed in the decision
to replace your valve, particularly if you have other serious health
issues.
Both commissurotomy and valve replacement are surgical
procedures. A commissurotomy can be either open-heart, where your chest is
opened and heart bypass is done through a heart-lung machine, or closed, where
an incision is made in the chest but a heart bypass is not done. The heart-lung
machines can increase risk.
Balloon valvotomy is a catheter-based
procedure (a catheter is threaded through a vein in your leg to your heart) and
therefore is not considered a surgical procedure. But it, too, carries some
risk. Much of this risk depends on the skill of the doctor doing the procedure,
and you should consider the number of procedures performed by the individual
doing your valvotomy when deciding to have the procedure. The overall mortality
rate for valvotomy is 1% to 3%, though in high-volume centers, it can be under
1%.1