Mitral stenosis refers to a heart valve defect. In this case, there is a narrowing at the opening of the mitral valve.
What is mitral stenosis?
In medicine, mitral stenosis is also known as mitral valve stenosis. There is a narrowing at the mitral heart valve, which separates the left ventricle from the atrium. The stenosis results in impaired blood flow between the left ventricle and left atrium. The mitral valve normally has an orifice area between 4 and 6 cm². If this area drops to about 2 cm², we are talking about mitral stenosis or mitral valve stenosis. This results in severe narrowing, which usually leads to pronounced symptoms. The symptoms are even more severe if the opening area of the heart valve drops to less than 1 cm². Mitral stenosis is one of the most common acquired heart defects. The female sex suffers more frequently from the disease than the male sex. Overall, mitral valve stenosis accounts for about 20 percent of all heart valve defects. In Europe, approximately three to four percent of all people suffer from a disease of their heart valves.
Causes
In most cases, the cause of mitral stenosis is rheumatic fever. This results from exposure to bacteria such as class A streptococci. This often affects the inner lining of the heart. The bacteria cause an inflammation of the inner lining of the heart (endocarditis), which in the further course passes on to the mitral valve. Thus, the heart valve is also composed of tissue from the inner lining of the heart. Sometimes mitral stenosis does not appear until 20 or even 30 years after rheumatic fever. In the case of an acute rheumatic fever, a heart valve defect occurs in about half of all patients. This causes the mitral valve to calcify, which in turn triggers its narrowing and restricted movement. Mitral regurgitation is often caused by inflammatory-degenerative processes or a survived heart attack. These processes are likely to affect parts of the heart that are important for the stabilization and opening of the valve apparatus. If these structures are impaired, the mitral valve leaflets overlap into the atrium as the heart pumps. Physicians differentiate mitral regurgitation between primary (organic) and secondary (functional) triggers. The most common primary causes include infections that directly damage the mitral valve. In contrast, a secondary cause involves an underlying disease from which the mitral valve is negatively affected. Occasionally, autoimmune diseases are responsible for the occurrence of mitral stenosis. In some patients, the valvular defect is also already congenital.
Symptoms, complaints, and signs
Mitral stenosis becomes noticeable through shortness of breath. It is caused by blood backing up toward the lungs. The backpressure causes the fluid portion of the blood to be forced into the lung tissue, making it difficult for oxygen to be transported into the blood, causing the patient to suffer from breathing problems. In most cases, shortness of breath manifests itself during physical exertion, as the heart is more active during this. In severe cases, breathing difficulties are also possible at rest. Some patients also suffer from hemoptysis. This causes solid blood components to leak into the lung passages, resulting in a reddish discoloration of the sputum. If mitral stenosis persists for a long time, changes in the heart are possible due to the pressure. Thus, there is a risk that dilatation of the left atrium will trigger atrial fibrillation. Atrial fibrillation is accompanied by disturbances in blood flow, so there is a risk of blood clots forming. If these are carried into the body, further clinical symptoms occur. Right heart strain results in blood backing up to the right heart, which may be manifested by leg edema or an enlarged liver. Some patients also suffer from blue discolored skin.
Diagnosis and course of the disease
If mitral stenosis is suspected, the physician first deals with the patient’s medical history. Subsequently, a physical examination takes place. During this, the physician uses a stethoscope to listen for suspicious heart murmurs.Other possible examination procedures include an ECG, an X-ray examination, a computer tomography (CT), a magnetic resonance imaging (MRI) and an echocardiography or a Doppler echocardiography. Right heart or left heart catheterization is also possible. The course of mitral stenosis is usually more favorable than with other heart valve defects. Without appropriate therapy, however, the patient’s life expectancy is considerably shortened in severe cases. Thus, affected individuals are at risk of death from right heart failure or embolism.
Complications
In general, mitral stenosis can cause life-threatening conditions and symptoms in the patient. First and foremost, the disease causes shortness of breath, which can further lead to loss of consciousness and, in the worst case, then death of the patient. Likewise, the individual organs are no longer supplied with sufficient oxygen, so that they can be damaged. The affected person suffers from a bloody cough and from severe fatigue and exhaustion. The liver is also enlarged by mitral stenosis, which can lead to pain and other complaints. Reduced oxygen transport also causes the skin to turn blue. If there is no treatment for mitral stenosis, the affected person may also die due to this disease. In most cases, treatment is carried out by taking medications that can relieve the symptoms of mitral stenosis. In this process, complications do not usually occur. These usually occur only if there is no early treatment of this disease. In severe cases, surgical intervention may also be necessary. Whether there will be a decreased life expectancy with this disease cannot be universally predicted.
When should you see a doctor?
Disturbances and irregularities of the heart rhythm are signs of a health condition that needs to be investigated and treated. If there is an incipient problem with breathing, clarification by a physician also becomes necessary. If there is shortness of breath, increased pulse rate or rapid fatigability, there is cause for concern. If daily tasks cannot be performed due to fatigue or tiredness, a doctor should be consulted. Sleep disturbances, headaches, malaise and a feeling of illness should be evaluated by a physician. If the general resilience decreases and physical activities can no longer be performed as usual, a doctor is needed. If there is a withdrawal from social as well as sporting activities, irritability or a reduced sense of well-being, a doctor should be consulted. If states of anxiety or panic develop due to the shortness of breath, the affected person needs help. A pale complexion as well as a blue coloration of the lips indicate an undersupply of oxygen to the organism. A visit to the doctor is necessary to prevent a life-threatening condition. Swelling or a feeling of pressure inside the body are further indications of a present disease. If functional disturbances occur, a diffuse sensation of pain develops or digestive impairment occurs, a doctor is needed. In the case of hemoptysis, a visit to the doctor is needed as soon as possible.
Treatment and therapy
Treatment of mitral stenosis is either conservative or surgical. In mild cases, the patient must take physical rest and medications such as diuretics. If pulmonary hypertension also exists, vasodilators such as nitrates are administered. If atrial fibrillation poses a risk of cardiac embolism, the patient is given beta-blockers or blood-thinning medications to counteract the embolism. If conservative treatment is not sufficient to improve mitral stenosis, surgical therapy may be appropriate to widen or restore the narrowed mitral valve. Balloon dilatation is one of the proven procedures. This involves inserting a balloon into the mitral valve region with a small catheter and inflating it, which causes the valve to dilate. Another procedure is commisurotomy. In this method, the surgeon removes the calcified valve tissue, restoring the mitral valve’s ability to function.
Outlook and prognosis
Mitral stenosis is one of the more slowly progressive diseases. This means that it often takes years for it to manifest clinically in affected individuals.Mitral stenosis is also frequently associated with bacterial infections and degenerative processes. In the long term, the disease leads to a significantly reduced pumping capacity of the affected heart. This often manifests itself in a clinical appearance with shortness of breath and reduced exercise tolerance of the patient. Completely untreated mitral stenosis would certainly lead to premature death of the patients. However, the prognosis is different for each individual patient, especially because mitral stenosis is usually rather insidious until it finally becomes clinically noticeable. The patient’s heart changes anatomically and functionally to adapt to the disease as best it can. However, this works differently for each patient. The survival rate for patients who require surgery is 89% for the next 8 years. The prognosis of the patients depends on how strong the pumping capacity of the diseased heart is. In patients with a more normal pumping function, the survival rate for 10 years is about 72%. Whereas in patients with impaired pump function, the 10-year survival rate is 32%. Sudden deaths are generally relatively rare at about 0.8%.
Prevention
To prevent mitral stenosis, avoidance of common underlying diseases is recommended. Thus, it is important to counteract a heart attack or diabetes, which can be done, for example, through a healthy diet.
Aftercare
Follow-up care for mitral stenosis is important after a surgical procedure in which a special mitral clip was inserted. After spending a night in the hospital’s intensive care unit, the patient is transferred to the regular hospital ward for about three to five days. There he is soon allowed to get up and move around again. In most cases, an improvement in symptoms such as shortness of breath can be felt shortly after the procedure. Following the operation, the patient is given certain medications, such as acetylsalicylic acid (ASA) or clopidogrel. Both belong to the group of active substances known as platelet aggregation inhibitors. These have the property of counteracting the clumping of thrombocytes (blood platelets) in the blood, thus preventing the formation of a dangerous blood clot. While clopidogrel is administered for about one month, acetylsalicylic acid, which has a weaker effect, is administered for at least six months. If the patient suffers from additional symptoms such as heart failure, other drugs such as ACE inhibitors, beta-blockers, diuretics or aldosterone antagonists must be taken. Every three to six months after surgery, there is a follow-up visit with the primary care physician. A cardiologist should also be seen once a year to check the condition of the heart and mitral valve. It is also recommended to participate in an outpatient heart failure group after completion of inpatient rehabilitation measures.
What you can do yourself
Adjustment and self-help for established mitral stenosis depend very much on the severity of the stenosis as well as the possible accompanying symptoms such as atrial fibrillation. In severe cases, which are also manifested by physical performance weakness and shortness of breath, any physical exertion should be avoided. Even if the subjective sensation is better than would be expected from the objective findings, physical and mental stress peaks should be avoided as far as possible. Mental or psychological stress peaks should be avoided if possible, because a sudden release of stress hormones by the sympathetic nervous system due to rising blood pressure results in additional stress on the left atrium. In the case of less severe mitral stenoses, which are hardly noticed even subjectively in the normal course of daily life, endurance sports such as golf and Nordic walking are recommended without incalculable stress peaks. On the other hand, ball sports such as soccer, tennis and handball should be avoided because they are associated with strong and previously unforeseeable stress peaks. Sports with a high static load, such as weightlifting and bodybuilding, can also have an unfavorable effect. Affected persons should therefore refrain from such sports. How high the individual load may be should be clarified in advance by a detailed examination of the mitral stenosis.Relaxation techniques that contribute to deep relaxation via mental exercises such as meditation or yoga and relieve the heart are also helpful.
