Mitral valve regurgitation, or mitral
regurgitation, is a condition in which the mitral
valve doesn't close tightly, allowing blood to flow
backward in your heart.
Your heart - a muscular pump in your chest - has
four valves, which open and close to keep blood
flowing in the proper direction through your heart.
The mitral valve connects the heart's upper-left
chamber (atrium) to the heart's lower-left chamber
(ventricle).
When the mitral valve doesn't function properly,
blood can't move through your heart or to the rest
of your body as efficiently. Mitral valve
regurgitation is also called mitral insufficiency,
or incompetence. The condition can leave you
fatigued and short of breath.
Fatigue
Treatment depends on the severity and progression
of your condition and signs and symptoms. You may
need heart surgery to repair or replace the valve.
Left unchecked, severe mitral regurgitation can lead
to congestive heart failure or serious heart rhythm
irregularities (arrhythmias).
Signs and symptoms
Signs and symptoms of mitral regurgitation depend on how severely and
quickly the condition develops. Most often mitral regurgitation is mild
and develops slowly. Because you may have no symptoms for decades, you
may be completely unaware that you even have this condition.
When signs and symptoms do develop, they may do so gradually because the
heart is able to compensate for the defect for some time. Mitral
regurgitation is often first suspected when your doctor hears a new
heart murmur. Sometimes, however, the disorder develops quickly, and you
may experience the abrupt onset of more severe signs and symptoms.
Indicators of mitral regurgitation include:
-
Shortness of
breath, especially with exertion or when you lie down
-
Fatigue,
especially during times of increased activity
-
Cough, especially
at night or when lying down
-
Awakening at night
with shortness of breath
-
Heart palpitations
sensations of a rapid, fluttering heartbeat
-
Swollen feet or
ankles
-
Heart murmur
Fatigue
Causes
Your heart, which is the center of your circulatory system, consists of
four chambers. The two upper chambers, the atria, receive blood. The two
lower chambers, the ventricles, pump blood.
Blood flows through your heart's chambers, aided by four heart valves,
which open and close to let blood flow in only one direction through
your heart:
-
Tricuspid valve
-
Pulmonary valve
-
Mitral valve
-
Aortic valve
The mitral valve, which lies between the two left chambers of your
heart, consists of two triangular-shaped flaps of tissue called
leaflets. The leaflets of the mitral valve connect to the heart muscle
through a ring called the annulus. Anchoring the mitral valve to the
left ventricle are tendon-like cords, resembling the strings of a
parachute, called chordae tendineae cordis.
Heart valves open like a trapdoor. The leaflets of the mitral valve open
when the left atrium contracts, forcing blood through the leaflets and
into the left ventricle. When the left atrium relaxes between heart
contractions, the flaps shut to prevent blood that has just passed into
the left ventricle from flowing backward, in the wrong direction.
When working properly, heart valves open and close fully. In mitral
regurgitation, the mitral valve doesn't close tightly. Some blood from
the left ventricle flows backward into the left atrium, instead of
forward into the aorta, with each heartbeat. Regurgitation refers to the
leakage (backflow) of blood through a heart valve.
Any condition that damages a valve can cause regurgitation. Mitral
regurgitation has several causes, including:
-
Mitral valve
prolapse.
Another problem of the mitral valve, mitral valve prolapse is a
condition in which the leaflets and supporting cords of the mitral
valve weaken. The result is that with each contraction of the left
ventricle, the valve leaflets bulge (prolapse) up into the left
atrium. This common heart defect may prevent the mitral valve from
closing tightly and lead to regurgitation. However, mitral valve
prolapse is common and the vast majority of people who have it never
develop severe regurgitation.
-
Damaged cords.
Mitral regurgitation may result from damage to the cords that anchor
the flaps of the mitral valve to the heart wall. Over time, these
cords may stretch or suddenly tear, especially in people with mitral
valve prolapse. A sudden tear of these cords can cause substantial
leakage through the mitral valve and may require emergency heart
surgery to repair.
-
Rheumatic
fever.
Rheumatic fever a complication of strep throat and once a common
childhood illness can damage the mitral
valve, leading to mitral regurgitation later in life. Rheumatic
fever can damage the mitral valve in two main ways. The infection
may cause the leaflets of the valve to thicken, limiting the valve's
ability to open. This results in narrowing of the valve, a condition
known as mitral stenosis. The infection may cause the leaflets of
the mitral valve to fuse somewhat together, preventing the valve
from closing tightly and leading to regurgitation. People with
rheumatic fever, which is still common in developing countries, may
have both mitral stenosis and mitral regurgitation.
-
Endocarditis.
The mitral valve may be damaged by endocarditis, an infection inside
the heart that can involve heart valves.
-
Deterioration
of the valve with age.
The mitral valve
opens and shuts tens of thousands of times every day of your life.
Sometimes age-related wear and tear on the valve causes mitral
regurgitation.
-
Prior heart
attack.
A heart attack can damage the area of the heart muscle that supports
the mitral valve, affecting the function of the valve. In fact, if
the damage is extensive enough, a heart attack may result in sudden
and severe mitral regurgitation.
-
Congenital
heart defects.
Some babies are born with defects in their heart,
including a mitral valve that's leaky.
heart
attack
Severe mitral regurgitation of any cause can weaken your heart. When
the left ventricle contracts in a heart with mitral regurgitation, some
blood flows backward into the left atrium instead of flowing forward
into the aorta. As a result, less blood flows out to the rest of your
body. In response, the left ventricle may enlarge so that it can pump
more blood with each heartbeat. At first this adaptation helps your
heart beat with more force. But eventually, the change weakens your
heart and may lead to heart rhythm irregularities, such as atrial
fibrillation.
Risk factors
Several factors can increase your risk of mitral valve regurgitation,
including:
-
A history of
mitral valve prolapse or mitral stenosis.
However, having either condition doesn't necessarily mean you'll
develop mitral regurgitation. In fact, most people with mitral valve
prolapse never develop severe regurgitation.
-
A past heart
attack.
A heart attack can damage your heart, affecting the
function of the mitral valve.
-
Use of certain
appetite suppressants.
People who took fenfluramine or dexfenfluramine for more than four
months may have an increased risk.
-
Infections,
such as endocarditis or rheumatic fever.
Infections can
damage the mitral valve.
-
Age.
By middle age, many people have some degree of mitral regurgitation
caused by natural deterioration of the valve. However, mitral
regurgitation progresses to cause symptoms in only a small
percentage of older adults.
heart
attack
When to seek medical advice
If you develop signs and symptoms that suggest mitral regurgitation or
another problem with your heart, see your doctor right away. Sometimes,
the first indicators of mitral regurgitation are actually those of its
complications, including congestive heart failure. Congestive heart
failure is a condition in which your heart can't pump sufficient blood
to the rest of your body, causing shortness of breath, fluid buildup and
fatigue.
Fatigue
However, mitral regurgitation is commonly discovered earlier, during a
routine examination when your doctor listens to the sounds of your heart
with a stethoscope. Mitral regurgitation can cause an abnormal heart
sound (heart murmur). Your doctor may have already informed you that you
have a heart murmur caused by mitral regurgitation.
When mild, mitral regurgitation may never pose a serious threat to your
health. But when severe, mitral regurgitation may cause heart
complications and require surgery to correct.
Screening and diagnosis
If you have signs and symptoms of mitral regurgitation, you may undergo
several types of diagnostic tests. But first your doctor talks with you
and asks questions about your health, including your symptoms, prior
tests and history of heart disease in your family.
Next, your doctor performs a physical examination. He or she listens to
your heart sounds with a stethoscope. Mitral regurgitation produces a
distinct heart murmur. The murmur is the sound of blood leaking backward
through the mitral valve.
With this information, your doctor decides which tests to request so
that he or she can make a diagnosis and develop a treatment plan. You
may be referred to a cardiologist a doctor who specializes in the
study of the heart and its function. Common tests used to diagnose heart
valve problems include:
-
Chest X-ray.
With an X-ray of your chest, your doctor can see the size and shape
of your heart to determine whether the left ventricle is enlarged. A
chest X-ray also allows your doctor to evaluate your lungs. Mitral
regurgitation may result in blood backing up into your lungs, which
causes congestion that's visible on an X-ray.
-
Electrocardiogram
(ECG).
In this test, patches with wires (electrodes) are attached to your
skin to measure the electrical impulses given off by your heart.
Impulses are recorded as waves displayed on a monitor or printed on
paper. An ECG gives information about heart rhythm and, indirectly,
heart size. With mitral regurgitation, the left ventricle may be
enlarged and you may have heart rhythm irregularities (arrhythmias).
-
Holter
monitor.
A Holter monitor is a portable device that you wear to record a
continuous ECG, usually for 24 to 72 hours. Holter monitoring is
used to detect intermittent heart rhythm irregularities that may be
associated with mitral regurgitation.
-
Echocardiogram.
This test uses sound waves to produce an image of your heart. In an
echocardiogram, sound waves are directed at your heart from a
wand-like device (transducer) held on your chest. The sound waves
bounce off your heart and are reflected back through the chest wall
and processed electronically to provide video images of your heart
in motion. An echocardiogram helps your doctor get a close look at
the mitral valve and how well it is or isn't working. A specific
type of echocardiogram, a Doppler echocardiogram, may be used. It
allows precise measurements of the volume of blood flowing backward
through the mitral valve.
-
Transesophageal
echocardiogram.
This type of
echocardiogram allows an even closer look at the mitral valve. The
esophagus, the tube that runs from your throat to your stomach, lies
close to your heart. In a traditional echocardiogram, a transducer
is moved across your chest. In a transesophageal echocardiogram, a
small transducer attached to the end of a tube is inserted down the
esophagus. Because the esophagus lies close to your heart, having
the transducer there provides a clearer picture of the mitral valve
and blood flow through it.
-
Exercise tests.
Various exercise tests can help measure your tolerance for activity
and check your heart's response to exertion (exercise).
-
Cardiac
catheterization.
In this procedure, a doctor threads a thin tube (catheter) through a
blood vessel in your arm or groin into your heart. The catheter is
used to deliver dye into the heart chambers and the blood vessels of
your heart. The dye, appearing on X-ray images as it moves through
your heart, gives your doctors detailed information about your heart
and heart valves. Some catheters used in cardiac catheterization
have miniature devices (sensors) at the tips that can measure
pressure within heart chambers, such as the left ventricle.
Complications
Mitral regurgitation puts you at risk of endocarditis, an infection of
the heart's inner lining (endocardium). Typically, the infection
involves one of the heart valves, especially if it's already damaged. If
the mitral valve is damaged, it's more prone to infection than is a
healthy valve. You can develop endocarditis when bacteria from another
part of your body spread through the bloodstream and lodge in your
heart. If you have mitral regurgitation, your doctor may recommend that
you take antibiotics before certain dental or medical procedures that
may increase the likelihood of bacteria entering your bloodstream and
causing an infection in your heart.
When it's mild, mitral regurgitation may never pose a serious threat to
your health. But when it's severe, mitral regurgitation may lead to
these complications:
-
Congestive
heart failure.
In congestive heart failure, your heart is unable to pump sufficient
blood to meet your body's needs. Fluid and pressure build up in your
lungs as a result of mitral regurgitation. This can put a strain on
the right side of your heart, leading to ankle swelling (edema).
People with congestive heart failure experience shortness of breath
and fatigue and may wake up at night feeling short of breath.
-
Atrial
fibrillation.
This is an irregular heart rhythm in which your heart's upper
chambers (atria) beat chaotically and rapidly. Atrial fibrillation
is worrisome because it can lead to blood clots forming in your
heart. These blood clots may break loose from your heart and travel
through your bloodstream to your brain, causing a stroke. Other
irregular heartbeats (heart arrhythmias) also may occur in people
with mitral regurgitation.
Stroke
Treatment
Treatment for mitral regurgitation depends on the severity and
progression of your condition. Treatment focuses on maximizing your
heart's function, minimizing your signs and symptoms, and avoiding
future complications.
Observation
Some
people, especially those with mild regurgitation, need no specific
treatment. However, even if you don't have signs and symptoms with
mitral regurgitation, the condition requires monitoring by your doctor.
You'll need regular evaluations, with the frequency depending on the
amount of regurgitation.
Observation isn't the same as ignoring the condition. Actively observing
the stability or the progression of the disorder is important so that
you can receive the right treatment at the right time.
Medications
Currently, no medication can correct a deformity of a mitral valve.
Medications such as diuretics are available to relieve fluid
accumulation in your lungs or legs, which can accompany mitral
regurgitation. High blood pressure makes mitral regurgitation worse, so
if your blood pressure is elevated your doctor may prescribe medication
to help lower it. Following a low-salt diet helps prevent fluid buildup
and helps control blood pressure.
high blood pressure
Antibiotics are used to help prevent endocarditis. If you have mitral
regurgitation, always follow precautions to prevent endocarditis. Ask
your doctor or nurse for these guidelines.
Surgery
Your
mitral valve may need to be surgically repaired or replaced. Naturally,
if you feel well, you may question the need for open-heart surgery, if
suggested by your doctor, to correct your mitral valve. Strange as it
may seem, you can have very bad mitral regurgitation and yet feel well.
This is because the heart is generally very adept at counteracting
deficiencies caused by a leaky mitral valve.
However, the problem is that if the valve isn't repaired or replaced,
the strength of your heart muscle may continue to decline so far that
even once the valve is operated on, the problem with the weakened pump
remains. Additionally, if damage to your heart becomes too severe,
surgery can't be safely performed. So it's important to have surgery
early enough that your heart doesn't become permanently weakened.
Over the years, extraordinary progress has been made in surgery to
repair the mitral valve, minimizing the risk of surgery. Discuss the
risks and benefits of surgery with your doctor. Surgical procedures
include:
-
Valve
repair.
Mitral valve repair is a surgery to preserve your own valve. The
surgeon can modify the original valve (valvuloplasty) to eliminate
backward blood flow. Surgeons can repair the valve by reconnecting
valve leaflets or by removing excess valve tissue so that the
leaflets can close tightly. Sometimes repairing the valve includes
tightening or replacing the ring around the valve (annulus). This is
called an annuloplasty.
-
Valve
replacement.
Valve replacement is done when valve repair isn't possible. In valve
replacement surgery, the damaged mitral valve is replaced by an
artificial (prosthetic) valve. The two types of artificial valves
are mechanical and tissue. Mechanical valves, which are made of
metal, may last a long time. However, if you have a mechanical
valve, you must use an anticoagulant medication, such as warfarin (Coumadin),
for the rest of your life to prevent blood clots from forming on the
valve. If a blood clot forms on the valve, the valve won't work
properly. If a clot breaks free of the valve, it could lodge in an
artery to your brain, blocking blood flow to your brain and causing
a stroke. Tissue valves are made from biologic tissue such as a
pig's valve. These kinds of valves are called bioprostheses. They
may wear out over time and may need replacement in another
operation. However, an advantage of the tissue valve is that you
don't have to use long-term anticoagulant medication. Your doctor
can discuss with you the types of heart valves. The results with
either type of valve tend to be very good.
Stroke
Mitral valve repair or replacement generally involves open-heart
surgery, done under general anesthesia. Through an incision the length
of your breastbone (sternum), your heart is exposed and connected to a
heart-lung machine that assumes your breathing and blood circulation
functions during the procedure. Your surgeon then replaces or repairs
the valve. After the operation, you'll spend one or more days in an
intensive care unit, where your heart function and general recovery are
closely monitored.
Surgeons are working on developing less invasive techniques to treat
valve disorders, such as repairing mitral valves using endoscopy, which
uses smaller incisions. Such procedures, however, aren't widely
available. Eventually it may even be possible to replace the mitral
valve using cardiac catheterization techniques that don't require
open-heart surgery.
Mitral regurgitation can be eliminated with surgery. The prognosis is
generally very good after surgery. However, let your doctor know if you
develop new or worsening signs and symptoms after treatment. Mitral
regurgitation can recur.
Prevention
One possible way to prevent mitral regurgitation is to prevent rheumatic
fever. You can do this by making sure you see your doctor when you have
a sore throat. Untreated strep throat can develop into rheumatic fever.
Fortunately, strep throat is easily treated with antibiotics.
You can help prevent the complication endocarditis, an infection of the
mitral valve and inner heart, by taking antibiotics before certain
dental and medical procedures. Ask your doctor if and when you should
take antibiotics to prevent endocarditis if you have mitral
regurgitation.
If you have mitral valve prolapse with mitral regurgitation, it's
important to have your doctor regularly check the amount of
regurgitation through regular physical examinations and follow-up
echocardiograms when needed.
Self-care
To maximize your quality of life if you have mitral regurgitation, your
doctor may recommend that you:
-
Eat a
heart-healthy diet.
Food doesn't directly affect mitral regurgitation. However,
developing coronary artery disease blockages of arteries that feed
your heart may lead to heart attacks with further weakening of the
heart muscle. To follow a heart-healthy diet, eat low-fat foods and
check your cholesterol levels regularly. Also, your doctor may
suggest that you limit your salt intake.
-
Maintain a
healthy weight.
Excess weight may make you short of breath and may complicate heart
surgery if you ever need it. Keep your weight within a range
recommended by your doctor.
-
Check your
blood pressure regularly.
Control of high blood pressure is extremely important if you have
mitral regurgitation.
-
Cut back on
caffeine.
Irregular heartbeats (arrhythmias) may occur in people with mitral
regurgitation. Arrhythmias may worsen if you consume caffeine. Ask
your doctor about drinking beverages with caffeine, such as coffee
and soft drinks.
-
Cut back on
alcohol.
Heavy alcohol consumption can cause arrhythmias and can make your
symptoms worse. If you have mitral regurgitation, ask your doctor
about the effects of drinking alcohol.
-
Exercise.
Physical activity may help to keep your body fit and may help you to
recover faster if you ever need heart surgery. Your doctor usually
gives you guidelines for your exercise program. Don't stop
exercising if you've received a diagnosis of mitral regurgitation.
If you find that you're unable to do things because of mitral
regurgitation, talk to your doctor.
-
See your doctor
regularly.
Establish a regular evaluation schedule with your cardiologist.
-
See your
dentist regularly.
Receive regular
dental care, following recommendations for the prevention of
endocarditis for any dental procedure.
If you're a woman with mitral regurgitation, discuss family planning
with your doctor before you become pregnant, because your heart works
harder during pregnancy. How a heart with mitral regurgitation tolerates
this extra work depends on the degree of regurgitation and how well your
heart pumps. Should you become pregnant, your cardiologist and
obstetrician need to evaluate you throughout your pregnancy, labor and
delivery, and after delivery.
coronary artery disease
Fatigue
high blood pressure