Your heart is comprised of four chambers: the upper "atria" and
the lower "ventricles. The heart also has four valves: the "tricuspid",
the "pulmonary", the "mitral", and the "aortic". The valves are
one-way doors which allow blood to flow as your heart contracts
and relaxes. Each contraction and relaxation comprise a heartbeat.
The mitral valve is
located between the left atrium and left ventricle . It is so
named because of its slight resemblance to the mitre, a two peaked
clerical cap. More aptly, its appearance has been compared to
two halves of a parachute arranged canopy to canopy.
The mitral valve has
two flaps or leaflets which are white, translucent fibrous membranes
that stretch over the opening (annulus) between the atrium and
ventricle. Even though the leaflets are thin, they are strong
and tough.
The leaflets form the
one-way door that controls the flow of blood. The front leaflet
is longer and wider than the back leaflet. They are anchored and
kept closed during ventricular contraction by papillary muscles
which are part of the ventricle. The muscles are attached to the
mitral valve by thin but strong fibrous bands of tissue called
"chordae tendineae".
Blood passes from the
left atrium through the mitral valve to the left ventricle. From
there the blood is pumped out of the heart and to the rest of
your body.
Mitral valve prolapse
is the most frequently diagnosed valvular deformity
Sometimes the mitral
valve may be too large to fit snugly in its frame of muscles and
cords. It will then bow or prolapse. When this happens, the valve
may not close properly. Blood may sometimes leak backwards into
the left atrium when the heart contracts. A moderate leak can
enlarge the left atrium and cause an arrhythmia (irregular heart
rate or rhythm) or increase the risk of an infection of the valve.
This condition of leaking is variously known as "incompetence,"
"insufficiency, or "regurgitation."
If you have mitral
valve prolapse you may have absent, mild, moderate, or severe
mitral regurgitation. Most often, mitral valve prolapse is associated
with only minimal mitral regurgitation.
What
is a heart murmur?
A murmur is an abnormal blood flow your doctor can hear with a
stethoscope. It can be caused by regurgitation of blood as well
as by other heart valve abnormalities. Murmurs can also be caused
by abnormal blood flow patterns from other heart problems or by
increases in blood flow through a normal heart, as is often the
case during pregnancy or with severe anemia. The location, intensity
and quality of the murmur can give your doctor clues about its
cause and whether it is a sign of significant heart disease.
What are the symptoms of mitral
valve prolapse?
Most people with mitral prolapse will not have any symptoms. Although
some people experience palpitations, shortness of breath, chest
pain, lightheadedness, rapid heart beat, the precise reason for
these symptoms is not clear.
Some people who have mitral valve
prolapse also experience anxiety or panic attacks. Again, the
reason for this connection has not been determined.
How is mitral valve prolapse diagnosed?
Your doctor may diagnose mitral valve prolapse during a regular
physical examination by listening to your heart through a stethoscope.
This is called, "auscultation". Often, he will examine you in
three positions: standing, lying supine, and lying on your left
side. Your doctor will be listening for a sound called a "click"
which indicates prolapse. The click is caused by the tensing of
the chordae tendineae and the hammocking of the mitral valve leaflets.
Your doctor may hear multiple clicks.
If your doctor suspects that you have mitral
valve prolapse, he may order a painless diagnostic test called
a 2D echocardiogram (sound wave test) for further confirmation
and information.
Additional testing may include: an electrocardiogram,
a chest x-ray, an exercise or pharmacological stress test, a Holter
monitor test, or a cardiac catheterization. Your chest x-ray will
probably be normal unless you have severe mitral regurgitation.
If you have chest pain or discomfort, your doctor may order some
of these tests to rule out coronary artery disease.
What causes mitral valve prolapse?
If you have mitral valve proplapse, you were probably born with
the tendency and your condition may have worsened over time. Dehydration
can exacerbate the situation. Dehydration due to long car or plane
rides tends to slightly decrease the size of the heart (and the
valve's supportive structures), but the valve remains the same
size. The result is that the valve is too large and can "hammock"
or "bow".
What can I do to prevent mitral valve prolapse?
You cannot prevent mitral valve prolapse. or prevent it from worsening,
but most often no treatment is needed and mitral valve prolapse
remains mild with no consequence.
How is mitral valve prolapse treated?
If you have mild to moderate mitral valve prolapse, without leakage
of blood, you will not need treatment. If you do have moderate
leakage, the resultant congestion can be lowered with diuretic
medication. (water pills). If the prolapse has caused arrhythmias,
your doctor can treat them. with a variety of medications.
If you have symptoms, your doctor may treat them with drugs.
For example, she may give you Beta Blocker medication for anxiety
or panic attacks.
Severe mitral prolapse is rare. If you have this condition, you
may have to eventually undergo valve repair or replacement.
What will my life be like with mitral valve prolapse
The vast majority of people who have mitral valve prolapse have
an excellent prognosis and can lead normal lives.
If you have mitral regurgitation associated with mitral valve
prolapse, and you are about to undergo a surgical procedure or
have dental work, you should take antibiotics to prevent infection.
If you have moderate to severe mitral regurgitation, you should
see your physician regularly for evaluation.
What are the complications of mitral valve prolapse?
For most people, mitral valve prolapse is completely benign. In
rare cases, people develop infections of the heart (endocarditis),
palpitations due to cardiac arrhythmic distrubances, and even
more rarely, sudden death.