Heart valve defects: Description
The term heart valve defect or valvular disease is an umbrella term for an altered, leaky (insufficiency) or narrowed (stenosis) heart valve. Different symptoms occur depending on the affected heart valve and the type of defect.
Heart valves have a very important valve function in the blood flow through the heart. They ensure that the blood can only flow in one direction. The heart valves are opened and closed by the pressure and flow of the blood.
Frequency of heart valve defects
A distinction is made between congenital and acquired heart valve defects. The bicuspid aortic valve with two instead of the usual three pockets is the most common congenital heart valve defect. The majority of heart valve defects affect the left side of the heart, where the mitral and aortic valves are located.
In Europe and North America, the most common acquired heart valve defect is mitral valve insufficiency. However, aortic valve stenosis, the second most common valve defect, needs to be treated even more frequently. It usually occurs at an advanced age due to calcification of the valve.
Narrowed heart valves (valve stenosis)
The two most common heart valve stenoses are aortic valve stenosis and mitral valve stenosis. Depending on the severity, a distinction is made between low-, medium- or high-grade heart valve stenosis.
Leaky heart valves (valve insufficiency)
Patients whose heart valves do not close tightly are said to have valve insufficiency. Despite a closed heart valve, the blood flows back into the section where the pressure is lower – during the contraction phase of the heart muscle (systole) from the ventricle into the atrium or during the relaxation phase (diastole) from the pulmonary or aorta back into the ventricle.
The additional blood volume flowing back (volume load) causes the ventricle to expand (dilatation) and the heart muscle to become thicker (hypertrophy). Progressive valve insufficiency also leads to cardiac insufficiency.
Aortic valve insufficiency (also known as aortic insufficiency) and mitral valve insufficiency (mitral insufficiency) are the two most common types of heart valve insufficiency.
Heart valve prolapse
Some patients have several heart valve defects at the same time. If a single valve is leaking and narrowed at the same time, doctors speak of a combined heart valve defect or combined vitium.
Heart valve defects: symptoms
The symptoms depend on the severity of the heart valve defect and its location. Many heart valve defects do not cause any symptoms for a long time and are therefore not noticed. However, there are also acutely occurring heart valve defects, such as mitral valve stenosis after rheumatic fever, which cause (clear) symptoms early on.
The heart can compensate for many valve defects for a certain period of time. In the long term, however, they overload the heart and gradually lead to heart failure (cardiac insufficiency). The heart valve defect is often only noticed when symptoms of heart failure appear.
Overall, the symptoms of heart valve defects are similar in the case of stenosis and insufficiency of the heart valves. The most important signs are pressure and tightness around the sternum and rapid fatigue. Fainting spells are also possible.
Heart valve defect symptoms of the left ventricle
The symptoms of heart valve defects in the left ventricle are mainly caused by a backflow of blood into the left atrium and the pulmonary vessels. Those affected usually feel more comfortable in an upright and seated position than when lying down.
Typical signs of mitral valve insufficiency are shortness of breath (especially at night and when lying flat) and coughing at night. Patients experience heart stumbling and/or palpitations, signs of a cardiac arrhythmia, particularly in advanced cases. Pulmonary edema develops as a result of blood backing up into the lungs. If the blood backs up into the right ventricle, neck veins protrude. Due to the unfavorable flow conditions, blood clots can form in the left atrium, which can enter the circulation and cause serious complications (e.g. stroke).
Common symptoms of aortic valve stenosis are fluctuations in blood pressure and low blood pressure with dizzy spells and even fainting. As the coronary arteries are supplied with blood from the aorta, the heart muscle, which is working harder, receives too little blood. Patients feel pain or pressure in the chest (angina pectoris), which can increase with exertion. Shortness of breath and sometimes muscle pain occur during exertion.
Patients with aortic insufficiency complain of shortness of breath. A strong pulsation of the carotid artery (Corrigan’s sign) can be observed, which can lead to an implied nodding of the head with each heartbeat (Musset’s sign). Increased pulsation of the vessels (Quincke’s sign) is also noticeable in the area of the nail beds.
If the heart valves in the right side of the heart (pulmonary and tricuspid valves) no longer work properly as a result of heart valve defects, there is a long-term risk of right-sided heart failure. However, right-sided heart valve defects only lead to noticeable symptoms when they are already well advanced. The symptoms are caused by the strain on the right ventricle and the right atrium, which are weakened by the extra work.
As a result, the blood can no longer be pumped into the lungs in sufficient quantity and builds up in front of the heart. This can lead to the following symptoms:
- shortness of breath
- Rapid fatigue
- Blue coloration of the (mucous) skin (cyanosis)
- Water retention in the legs (edema) and abdomen (ascites)
- Blood congestion in the superficial neck vessels
- Exercise-induced pain in the chest and in the area of the liver (under the right costal arch)
- Congestion in other organs such as the stomach (loss of appetite, nausea) or kidneys (risk of renal insufficiency)
Heart valve defects: causes and risk factors
Heart valve defects can be either congenital or acquired. The majority of heart defects are acquired.
Congenital heart valve defects
In younger people, a heart valve defect in the aortic valve is usually the result of a defective valve system. The aortic valve then consists of only two instead of three pocket valves (so-called bicuspid aortic valve).
Acquired heart valve defects
Wear and calcification of the heart valves can lead to various heart valve defects with increasing age. Calcification of the aortic valve is particularly common. Calcification causes both valve narrowing and leakage.
Inflammations
Infections and inflammation of the heart muscle (myocarditis) or the inner lining of the heart (endocarditis) sometimes also result in heart valve defects. This is usually a case of heart valve insufficiency. The rarer heart valve defects of the right side of the heart are also primarily caused by infections of the inner wall of the heart.
In addition to mostly bacterial pathogens, autoimmune diseases such as systemic lupus erythematosus (LE) can also lead to endocarditis (Libman-Sacks endocarditis). In its late stages, sexually transmitted syphilis sometimes triggers inflammation of the aorta, which spreads to the aortic valve (syphilitic aortitis).
Rheumatic fever
Rheumatic fever particularly frequently affects the mitral valve. Streptococcal infections are therefore treated with antibiotics as a preventative measure, especially in children. As a result, cases of mitral valve stenosis, for example, are already on the decline in industrialized nations.
Heart attack
A heart attack also sometimes causes heart valve defects. The lack of oxygen damages the so-called papillary muscles in the heart chambers, which are attached to the large leaflet valves (mitral and tricuspid valves) by chordae tendineae. If they no longer function properly or even tear, they no longer hold the valve leaflet attached to them. During contraction of the ventricle, the valve flaps back into the atrium. There is a risk of acute, severe leakage of the corresponding heart valve.
If the ventricular wall dilates after a myocardial infarction, this may also cause a leaky heart valve defect. This is also a risk in dilated cardiomyopathy, a heart muscle disease in which the heart chamber expands.
Aortic dissection
Cardiomegaly
Various diseases such as high blood pressure, heart muscle disease, thyroid dysfunction or severe anemia can lead to abnormal heart enlargement (cardiomegaly). As the heart valves do not grow with the heart, they become leaky.
Autoimmune diseases
Autoimmune diseases such as Takayasu’s arteritis (an inflammation of the large blood vessels) or genetic disorders of connective tissue metabolism (e.g. Marfan syndrome) also cause heart valve defects such as aortic valve or mitral valve insufficiency.
Heart valve defects: examinations and diagnosis
The specialists for heart valve defects are cardiologists and cardiac surgeons. They will first ask you questions such as:
- Do you suffer from shortness of breath or heart pain during exercise?
- How many flights of stairs can you climb without stopping?
- Have you recently been acutely ill with a fever?
- Have you recently had a medical procedure, including dental surgery?
- Do you have any known heart disease?
- What other illnesses do you suffer from?
Electrocardiogram
Heart valve defects sometimes trigger cardiac arrhythmias. Mitral stenosis, for example, often causes what is known as atrial fibrillation. The doctor recognizes this by means of an electrocardiogram (ECG). If cardiac arrhythmias occur repeatedly but only sporadically, a long-term ECG worn by the patient for at least 24 hours may help.
Laboratory tests
A blood test provides indications of an active inflammatory process, among other things. Doctors also use it to determine (in)direct heart values, such as creatine kinase (CK) and BNP (brain natriuretic peptide). Particularly if endocarditis is suspected, several blood cultures must also be taken, in which microbiologists search for bacteria. Another important blood test is the blood gas analysis (from capillary blood or arterial blood). This is because the oxygen content of the blood can provide important information in the case of major heart valve defects.
Imaging examinations
If the physical examination reveals a suspected heart valve defect, the doctor will perform a cardiac ultrasound (Doppler echocardiography). With the help of this, the examiner recognizes, for example, the heart contour and changes to the heart valves. He can also see – using Doppler technology – how the blood flows through the heart valves.
Detailed images are obtained using cross-sectional imaging. MRI technology (cardio-MRI) or computer tomography (CT) are used for this purpose. However, they are rarely used for a pure heart valve defect.
Stress tests
Both cardiac ultrasound examinations and ECGs can also be carried out under physical stress (on an ergometer or with heart-stimulating medication). These examinations clarify exercise-dependent symptoms. In the early stages, heart valve defects often only become apparent during exertion. Exercise tests therefore help to assess the severity of heart valve defects.
Cardiac catheterization
With the help of a so-called cardiac catheter examination, doctors measure the pressure conditions in the heart and use a contrast agent to show whether coronary arteries are narrowed.
If the examiner injects a contrast agent into the left ventricle (ventriculography or levocardiography), the shape and function of the ventricle as well as any vitia can be visualized.
Some heart valve defects can be “repaired” during this examination. This is another reason why this invasive examination is usually performed at the end of the diagnostic process – unless an acute vascular disease of the heart (CHD, heart attack) is suspected. Doctors also want to rule out these diseases before a heart valve defect operation using cardiac catheterization.
The detailed diagnosis allows the severity classification, which is different for each heart valve. This classification is an important basis for treatment planning. Among other things, it is important to determine the ejection fraction. This value indicates as a percentage how much of the blood flowing into the ventricle is pumped out again per beat. In healthy hearts, the value is around 60 to 70 percent.
Heart valve defects: treatment
The treatment plan for a heart valve defect depends on the type of heart valve defect, the affected valve, the severity and also the general condition of the patient. Doctors also use measurements of heart function when choosing treatment. All factors are weighed up individually to determine the best therapy for the individual patient. However, doctors don’t just want to alleviate symptoms with treatment. The therapy also improves the prognosis and stabilizes the heart valve function.
Before each treatment, doctors talk to the patient again in detail. They mainly address the following questions:
- What is the patient’s wish?
- Is it a serious heart valve defect?
- Are there any symptoms associated with the heart valve defect?
- How old is the patient?
- Do the benefits of the treatment outweigh the risks?
- Which medical center is suitable for the procedure?
Medication
Medication helps to reduce cardiac arrhythmia, lower blood pressure, strengthen the heart’s pumping power and prevent blood clots. Among other things, doctors prescribe medication that increases urine excretion in order to reduce the (volume) load on the heart (diuretics). Other drugs lower the heart rate and thus reduce the work of the heart (beta-blockers). After the insertion of heart valves made of “foreign material”, anticoagulation medication is often necessary.
Endocarditis prophylaxis
In addition, in the case of a heart valve defect, it must always be borne in mind that antibiotic prophylaxis against infection should be carried out before medical interventions where there is a risk of infection and resulting inflammation of the heart. For this reason, patients should inform their treating physicians of the presence of a (treated) heart valve defect so that they can prescribe antibiotic therapy if necessary. This applies in particular to dental treatment as well as examinations and treatment of the gastrointestinal tract.
Interventional treatment
Medication
Medication helps to reduce cardiac arrhythmia, lower blood pressure, strengthen the heart’s pumping power and prevent blood clots. Among other things, doctors prescribe medication that increases urine excretion in order to reduce the (volume) load on the heart (diuretics). Other drugs lower the heart rate and thus reduce the work of the heart (beta-blockers). After the insertion of heart valves made of “foreign material”, anticoagulation medication is often necessary.
Endocarditis prophylaxis
In addition, in the case of a heart valve defect, it must always be borne in mind that antibiotic prophylaxis against infection should be carried out before medical interventions where there is a risk of infection and resulting inflammation of the heart. For this reason, patients should inform their treating physicians of the presence of a (treated) heart valve defect so that they can prescribe antibiotic therapy if necessary. This applies in particular to dental treatment as well as examinations and treatment of the gastrointestinal tract.
Interventional treatment
Heart valve replacement – different types
Mechanical valves or biological prostheses from humans or animals (heart components from cattle or pig valves) can be considered as valve replacements for heart valve defects.
Metallic heart valves last a very long time. However, blood clotting must be inhibited with special medication for the rest of the patient’s life, as otherwise blood clots can adhere to the artificial valve, clog it or come loose and lead to vascular occlusion.
No “blood thinning” is necessary for a biological valve replacement. However, biological heart valves must be replaced after a certain period of time, as their durability is limited. In addition to normal wear and tear, this may be due to the fact that the immune system recognizes the valves as foreign bodies and attacks them. A distinction is made between biological replacement valves from animals (xenograft), from a deceased person (homograft) and heart valves cultivated from stem cells of the affected person (autograft). How long such a valve will last is difficult to predict and depends on many factors.
Choosing a new heart valve
The trade-off between a long lifespan of the prosthesis and lifelong “blood thinning” must be decided on an individual basis. As a rule, biological heart valves are only used from the age of 60 due to their limited durability. Metallic heart valves tend to be selected for younger patients or for patients who already have to take “blood thinners” for life for other reasons. Exceptions are women who wish to have children and do not wish to be prescribed anticoagulant medication.
After the insertion of a prosthetic valve, a valve pass should be issued, a check-up should be carried out at least once a year and endocarditis prophylaxis should always be considered. Endocarditis prophylaxis is the preventive administration of antibiotics for treatments that carry a risk of infection. This must also be taken into account in particular during dental procedures.
Aortic valve insufficiency and stenosis
Under certain conditions, aortic valve insufficiency, as well as aortic valve stenosis, can be treated using the catheter technique (“TAVI”: Transaortic Valve Replacement). A folded replacement valve is inserted into a small tube via a groin vessel through the large arteries into the heart, where the valve can be unfolded and attached.
In a Ross operation, the aortic valve is replaced by the pulmonary valve. The pulmonary valve, which is under far less strain, is in turn replaced by a human donor valve. The advantage of this method is that no lifelong blood thinning is necessary, long-term function is very good and physical resilience is almost unrestricted. The main disadvantage is a possible malfunction of the donor valve. A Ross operation can only be performed by experienced specialists.
Doctors sometimes use balloon valvuloplasty to bridge the gap until the final treatment, for example in the event of an acute deterioration in the patient’s condition. This involves widening the valve using a balloon, which is attached to a catheter and guided to the heart via the blood vessels. This method is also used in children. This is because a valve prosthesis is difficult for them as it cannot grow with them.
Mitral valve stenosis
Initially, mitral valve stenosis can be treated with medication. These can also alleviate mild symptoms. Diuretics in particular are helpful in reducing the volume load on the narrowed mitral valve. Any existing cardiac arrhythmia should also be controlled with medication. As with aortic valve insufficiency, surgery should be considered in good time in the case of mitral valve stenosis if the symptoms progress or the measured cardiac function is reduced.
As an interventional treatment, the valve can be widened (balloon mitral valvuloplasty). This form of valve repair, which aims to separate the fused valve edges, can also be performed as part of an open operation (surgical commissurotomy). If there are contraindications, doctors replace the valve with a prosthesis.
Mitral valve insufficiency and mitral valve prolapse
Similar principles apply to the treatment of mitral valve insufficiency as to mitral valve stenosis. Surgery to treat this type of heart valve defect should be carried out when symptomatic and when (or better still before) there are signs of impaired heart function.
Nowadays, mitral valve repair can also be performed as an interventional procedure. This involves inserting a clip (MitraClip) into the heart. The clip is then fixed in place so that it holds the leaflets of the mitral valve together and compensates for the heart valve defect.
Heart valve insufficiency or mitral valve prolapse can also be repaired during an operation. In the case of mitral valve insufficiency, a ring can be inserted into the valve area to correct the heart valve defect. Gathering with special sutures can reduce the valve weakness. If repair is not possible, the valve can be surgically replaced. However, repair (reconstruction) is preferred to a valve prosthesis.
Special sutures are also used for mitral valve prolapse: cardiac surgeons use them to stitch the papillary muscle tendons to the edge of the mitral valve. Sometimes doctors first have to reduce or remove the abnormally large leaflet (the part that bulges out) and then sew parts of it back on.
Pulmonary valve insufficiency
Pulmonary valve stenosis
Pulmonary valve stenosis can be treated with medication. In the case of advanced pulmonary valve stenosis, a repair or valve replacement can be performed. Interventional and surgical procedures are also available for this type of heart valve defect, such as those used for mitral stenosis (balloon dilatation, surgical commissurotomy).
Tricuspid valve insufficiency and tricuspid valve stenosis
These rare heart valve defects are treated as soon as they affect cardiovascular function. Their symptoms are usually mild. If medication does not help, a repair of the valve can be attempted first. In the case of tricuspid valve insufficiency, for example, gathering the edge of the valve and inserting a ring to stabilize it (ring annuloplasty) is suitable. Valve replacement is also an option.
Sport for heart valve defects
Whether and in what form sport is possible for patients with heart valve defects depends on the type of malformation. The patient’s individual condition and well-being also play a role in the recommendation for exercise.
Before patients with a heart valve defect take up any physical activity, they should always consult the doctor treating them.
Whether people with a congenital heart valve defect can be active in sports always depends on the individual condition of the patient. There are no general recommendations.
Course of the disease and prognosis
Heart valve defects can not only limit the quality of life, but also the length of life, as the entire cardiovascular system suffers as a result. The prognosis for heart valve defects depends primarily on which heart valve is affected and whether the heart valve defect has already impaired heart function. If a major heart valve defect is not treated, it will lead to heart failure and a poor prognosis over time.
Mild heart valve defects often do not need to be operated on initially, but they do need to be treated. It is important to check a detected heart valve defect regularly (at least once a year). The heart specialist will check how well the previous treatment is working and whether new measures need to be taken. Take advantage of these examinations, as they can improve the prognosis for heart valve defects in the long term.
