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Patient information
Valvular
heart disease
Pathologies, diagnosis and treatment
1
Valvular heart disease
The term valvular heart disease covers
all diseases that affect the valves of the heart.
Heart valves are soft tissue structures between
the four heart cavities, two on the left (the mitral
and aortic valves) and two on the right (the tricuspid
and pulmonary valves). Their function is to prevent
the blood flowing back into the cavity it came from.
Sometimes, one or more of these valves fails
to work properly because of one of two types
of problem:
• Valve stenosis (or narrowing) prevents the valve
from opening fully which obstructs blood flow.
• Valve regurgitation (or leaky valve or valve
incompetence): when the valve cannot close
properly, it allows blood to leak backwards.
The same valve may be affected by both these
problems simultaneously.
Pulmonary
valve
(open)
Mitral
valve
(closed)
Tricuspid valve
(closed)
Aortic valve
(open)
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The most common forms
of valvular heart disease
These days, the most common valve problems in
adults are aortic stenosis and mitral insufficiency.
Other problems include aortic insufficiency, tricuspid
insufficiency and mitral stenosis.
Disease of the pulmonary valve is rare
What are the causes?
Causes vary according to the valve affected:
• Age-related degeneration (aortic stenosis, mitral
insufficiency and aortic insufficiency),
• Acute rheumatic fever (mitral and tricuspid
stenosis), a birth defect,
• Infection, i.e. endocarditis (all valves),
• Diseases that affect heart muscle (heart failure,
myocardial infarction) can impair valve function.
How does valvular heart disease develop?
Without treatment, valvular heart disease tends to
lead to dilatation of the atria or ventricles because
of the extra work solicited from the heart. The
symptoms are shortness of breath due to increased
pressure in the lung (pulmonary oedema), faintness
with loss of consciousness possible, palpitations
and episodes of cardiac insufficiency.
2
How is valvular heart disease discovered?
•S
ymptoms: shortness of breath on exertion
(and at a more advanced stage, at rest), angina
pectoris, loss of consciousness (aortic stenosis),
palpitations, pulmonary oedema, heart failure.
• Auscultation: a murmur (stenosal or regurgitant),
irregular heartbeat.
Sometimes, the absence of symptoms is not
in contradiction with the severity of the disease.
• Accurate diagnosis depends on
echocardiography using a probe either placed
on the chest (transthoracic ultrasonography)
or inside the oesophagus (trans-oesophageal
ultrasonography with local anaesthesia).
Echocardiography:
- Confirms the diagnosis of valvular heart disease,
be it stenosis or insufficiency,
- Measures the surface area of the valve,
- Estimates the severity of the problem,
- Measures the pressure gradient across the valve,
- Assesses the impact of the valvular disease
on dilatation of the cavities and the ability
of the heart muscle to contract.
For further details, see the “Echocardiography”
information sheet.
The criteria used to determine if surgery
is indicated are very precise and are based
on well-defined measurements.
Once it has been decided to operate,
the check-up will be complemented with:
• Coronary angiography
In a preoperative check-up to investigate
valvular heart
disease, coronary
angiography is an
invasive examination
that allows imaging
all the coronary
arteries and
Valvular heart disease
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identifying any areas that have been narrowed by
atheromatous plaque. If necessary, the results can
help with the decision about whether or not to treat
coronary arteries.
The examination is performed in a specially
equipped radiology unit.
This examination requires the injection of a contrast
medium opaque to X-rays. This makes it possible
to image all the coronary arteries.
Like any invasive method, coronary angiography
has risks. These are low but patients ought to be
aware of them:
• Allergic reaction.
• Complications at the puncture point in the artery.
• Cardiac and vascular complications.
• CT scan (in some cases)
In young patients,
if perfectly normal
coronary arteries
are found during
this examination,
coronary
angiography can be
avoided.
A CT scan can also give information about the
shape and size of the aorta coming out of the heart
when the aortic valve is involved (aortic aneurysm).
For further details, see the “CT Scan” sheet.
• Magnetic resonance imaging
Serious complications are very rare: by way of
reference, the results of a study of a large number
of patients, published in a medical journal, found
a risk of death of 0.8/1,000, a risk of neurological
problems (notably paralysis) of 0.6/1,000 and a
risk of myocardial infarction of 0.3/1,000. Other
less severe complications were reported, with an
incidence under 1%.
For further details, see the “Coronary artery
disease” sheet.
Since 2002, this
method has been
used at the Monaco
Cardio-Thoracic
Center, to examine
the heart muscle
and detect fibrosis
or evidence of past
infarction.
For further details, see the “MRI” sheet.
3
How is valvular heart disease treated today?
After drug treatment, invasive therapy may be
indicated, depending on the condition of the valves,
the impact on heart muscle and the symptoms:
• Surgical repair or valve replacement,
• In certain conditions, a percutaneous procedure
(Valvuloplasty of the mitral valve, or Transcatheter
aortic valve implantation - TAVI)
Surgical repair remains the reference treatment
for valvular heart disease.
1 - Surgery
Once it has been decided to operate, the surgical
possibilities are:
• Repair of the valve (the mitral, tricuspid or
occasionally aortic valve),
• Or replacement of the valve with either a
mechanical or a biological prosthesis.
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Valve repair
Repair is the treatment of choice for mitral
insufficiency, used whenever possible:
• Commissurotomy (incision of fused
commissures) is only carried out for mitral
stenosis secondary to rheumatic fever if the
valve is still flexible and the heart rate is regular
(sinus rhythm), preferably in children and young
women of child-bearing age.
• Plastic repair of the mitral valve may be
indicated for mitral insufficiency. In this type of
procedure, the abnormality of the papillary muscle,
valve or annulus is repaired, but the original valve
is conserved (plastic surgery inside the heart).
A prosthetic annulus is always implanted to correct
deformation of the mitral opening.
• Tricuspid valve repair for functional tricuspid
insufficiency due to dilatation of the right
ventricle.
• In some cases of simple tricuspid insufficiency,
genuine plastic surgery can repair the valve
by enlarging it.
• If there is an aneurysm of the ascending aorta,
the aortic valve can sometimes be repaired.
Valve replacement
Prosthesis can be implanted in the orifice
of the aortic or mitral valve and, less often,
the tricuspid valve. Two or even three heart valves
can be replaced.
Whether or not to undertake replacement and
choice of the type of prosthesis (mechanical or
biological) are decided, in concert with the patient,
on the basis of a series of different criteria:
• The patient’s age,
• Presence or absence of an irregular heartbeat
necessitating anticoagulant therapy,
• Advantages and risks of long-term anticoagulant
treatment (anti-Vitamin K),
• The condition of the heart muscle tissue,
• The patient’s lifestyle.
Mechanical valves consist of a cage made of a
metal-carbon alloy with a base that can be fixed
on the annulus of the valve, together with a mobile
system, either a disk or flaps.
Their advantage is solidity (Starr® valves
implanted 30 years ago are still working perfectly).
The disadvantage is that patients must take
anticoagulant drugs all their lives; if these drugs
are too powerful, there is a risk of bleeding and
if they are not powerful
enough, the risk is of
thrombosis and embolism
(clot formation).
Biological valves or
bioprostheses are made
of a Dacron®-coated
Two-flap
mechanical valve
metal frame holding three
biological tissues, either
from pigs or made from the pericardium of young
cattle. The bioprosthesis has a metal ring lined with
a silicone cushion which can be inserted on the
annulus of the valve.
New “stentless” bioprostheses no longer have
a rigid ring and are
mounted on flexible tissue
in Dacron which cuts
down mechanical stress
and should prolong the
device’s lifetime.
The great advantage
of bioprostheses is
Bioprothesis
that they preclude
the need for lifelong
anticoagulant treatment
in the absence of
complete arrhythmia.
However, they may
deteriorate after
some fifteen years,
necessitating
a follow-up intervention.
Bioprostheses are
preferred in the elderly,
in women who want to
Stentless
conceive a baby, and
bioprosthesis
especially in those in
whom effective, closely monitored anticoagulant
therapy is contraindicated or impossible.
However, they can be used in physically active
patients of under 50 with a heart in good condition,
Valvular heart disease
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who do not want long-term anticoagulant
therapy and who accept the idea that a follow-up
intervention may well be necessary after about
fifteen years.
The older the patient, the slower is the deterioration
of bioprostheses.
Before the intervention
On admission, you should give the doctors
and nurses all the medical documents that you have
in your possession, including radiographs
and the results of any stress and laboratory tests.
You will undergo a biological check-up and the
care-providing team will explain how to prepare
for the operation (showering and mouth
hygiene) to prevent infection. The region to be
incised will be thoroughly depilated and disinfected.
How will the operation proceed?
With the patient under general anaesthetic, an
incision (sternotomy) is usually made in the middle
of the sternum or a mini-sternotomy (aortic valve).
A heart-lung by-pass machine is used to circulate
blood through the body and make it possible to
work inside a “dry” heart. During the intervention,
the heart muscle is protected by general and local
hypothermia, and stopped by cardioplegia.
The surgical procedure lasts about three or four
hours (depending on the complexity of the case).
Intensive care
After surgery, patients spend about 48 hours
in intensive care.
Patients are put on assisted ventilation for the first
few hours after which they are gradually taken off
until the tracheal tube can be removed.
Drugs are administered to relieve pain and fluids are
infused intravenously
to prevent dehydration.
Temporary thoracic
tubes are left in place
for a few days to drain
serum and blood from
the operative site.
A small percentage of patients will need a blood
transfusion.
Oral feeding is usually resumed the day after the
operation.
Discharge from intensive care
After about 48 hours, most patients are allowed
to get up and walk around. Regular sessions
of physical therapy help with the recovery of
functional independence and normal breathing.
Patients’ ECGs are permanently monitored (remote
monitoring).
What are the risks of valve surgery?
Like any kind of surgery, valve surgery is associated
with some level of morbidity and mortality. The risk
is assessed by the medical team (the cardiologist,
surgeon and anaesthetist) on the basis of the
state of the patient’s heart and general condition.
Complications may onset during or immediately
after the operation.
Some are common like abnormal heart rate
(arrhythmia, bradycardia) which might necessitate
the implantation of a pacemaker. Others are rarer
like postoperative infection (less than 2% in the
experience of C.C.M.) or neurological complications
(less than 1.5%). These risks will depend – as
the patient and his/her family are told – on the
specific features of the patient and the disease but
they are far lower than the risk associated with
spontaneous progression of the disease.
This is why surgical treatment is proposed.
Valvular heart disease
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What happens when you are discharged
from the Center?
Long-term surveillance of patients
with a replacement valve
You will be discharged either to your own home
or, more commonly, to a specialist convalescence
facility (according to the patient’s condition and
wishes).
As a rule, physical recovery is rapid. Driving
and sexual activity can be resumed as soon as
consolidation of the sternum has been obtained.
In most cases, replacement of the defective valve
will result in significant improvement, especially less
or no more shortness of breath on exercise.
The main limitation to the resumption of normal
activities is healing of the sternum. As with any
broken bone, it may take 6 – 12 weeks to obtain
definitive consolidation and, during this period, any
activity that might put the rib cage under significant
stress must be avoided.
Return to work
When a patient can go back to work will depend
on his/her recuperative capacities and the levels
of stress and physical activity associated with
his/her job. Your surgeon and cardiologist will be
able to help you decide when to return to work.
Will I need physical therapy?
A programme of cardiac
rehabilitation can speed
up recovery and help
you get back to your
normal daily activities
sooner. In addition,
you will be given advice
and recommendations
about lifestyle changes,
covering diet, weight
loss, physical exercise
and sports.
During this period, you will be told about
anticoagulant therapy and what carrying
an implant means.
The cardiologist and the surgeon will help you
match the rehabilitation programme to the condition
of your heart and your overall state of health.
Regular surveillance is indispensable by:
• your general practitioner,
• your cardiologist,
• and your dentist.
> You should see your general practitioner once
every two or three months, to check:
• The prosthesis by auscultation,
• Anaemia,
• Infection
• Efficacy of the anticoagulant treatment.
> You should be monitored by your
cardiologist once every six months, including
electrocardiography and echocardiography.
If it is suspected that the prosthesis is not
functioning properly, further investigation
may be required (e.g. MRI).
> You should see a dentist every six months
without fail and prophylactic antibiotics ought
to be taken before any dental procedure.
Remember to tell your dentist this.
“I am on anticoagulants”.
Remember to tell
your professional
health care providers!
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The anticoagulant drug
The anticoagulant drug administered
is an Anti-Vitamin K (Sintrom®, Préviscan®,
Coumadine®…) :
• Patients with an implanted mechanical valve have
to take it all the time for the rest of their lives.
• After mitral plastic surgery and the implantation
of a biological prosthesis, it must be taken
for three months.
• If the patient has arrhythmia, anticoagulant
therapy should be continued until the arrhythmia
regresses.
If a mechanical valve has been implanted,
anticoagulant therapy must never be stopped
for any reason.
> The efficacy of anticoagulant therapy is
monitored via International Normalised Ratio
(INR) measurements:
• between 2 and 3 if there is arrhythmia and after
a plastic procedure or implantation of a biological
prosthesis,
• between 3 and 4 for a mechanical mitral valve.
At the beginning of the course of treatment,
INR is checked every 8 days, then every 15 days,
and then every month until it appears to be stable.
If it is unstable, it should be checked more often
and it should also be checked a few days after
the dosage of the Anti-Vitamin K is changed.
Doses and laboratory test results should be
recorded in an Anticoagulant Treatment Record.
> Overdose may induce bleeding, e.g. prolonged
bleeding from a shaving cut or after brushing of
the teeth, easy bruising. INR should be checked
with a view to reducing the dosage.
> Some medications should be avoided because
they either potentiate anticoagulant activity
(tetracycline, aspirin, anti-inflammatory drugs)
or inhibit it (barbiturates).
> Intramuscular injection must be avoided
in patients on anticoagulant therapy.
> Some foodstuffs may modulate anticoagulant
activity:
• Do not eat more than one portion a day of foods
rich in Vitamin K, e.g. tomatoes, lettuce, spinach,
cabbage, broccoli and Brussels sprouts;
• Limit alcohol consumption to 2 units a day.
Prevention of infectious endocarditis
Carriers of a prosthetic heart valve are
susceptible to a serious complication in which
bacteria colonise the implanted device;
this is referred to as infectious endocarditis.
This complication – which is always serious –
manifests as chronic, low-level fever and can lead
to damage to the valve.
The source of the bacteria is often a dental
infection.
Thus, the danger of infectious endocarditis
necessitates:
> Watching out for any fever and notifying your
doctor;
> Assiduous treatment of any infection – dental,
lung, throat, urinary tract, skin – even a minor
one;
> Prophylactic antibiotic coverage before any
invasive procedure, such as dental care. Keep
your dentist informed about your heart disease.
> Rigorous mouth hygiene and teeth in perfect
condition.
Valvular heart disease
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Although prosthetic valves are not perfect and
require close surveillance, permanent anticoagulant
treatment in many cases and special measures
to prevent infectious
endocarditis, they
nevertheless let
patients live and work
normally as long as
they are implanted in
time, before the cardiac
muscle tissue has
sustained irreversible
damage.
2 - Special cases
Percutaneous treatment of the mitral valve
To correct mitral stenosis following rheumatic fever
in young patients in whom the valve is flexible
and the heart rate regular, percutaneous treatment
can often put off the need for surgery for several
years. These cases are particular and limited
in number.
Candidates for this
type of treatment will
be given a special
information sheet about
this procedure.
Percutaneous artificial aortic valve
implantation
This technique applies
to patients with severe
aortic narrowing who
cannot be operated on
or in whom surgery
carries a high risk –
usually the elderly or
patients with a history
of surgery in the past.
Edwards-Sapien valve
This alternative
to surgery permits
replacement of a defective aortic valve with
a bioprosthesis using one of two methods:
• cardiac catheterisation in which the artificial valve
is transported to the heart via the femoral artery,
• or implantation in a minimally invasive procedure,
through a tiny opening in the chest over the apex
of the heart below the left breast (a transapical
approach).
This technique is still being assessed and, according
to current cardiology guidelines, it should only be
considered for a given patient after two surgeons
have decided that surgery is contraindicated.
After deliberations between physicians and
surgeons, candidates for this type of treatment
will be given a special information sheet about
the procedure.
Dilatation
of mitral valve
Bibliography
Société Française de Cardiologie
Fédération Française de Cardiologie
© MONACO CARDIO-THORACIC CENTER - december 2012