In mitral valve regurgitation, the heart valve located between the left atrium and the left ventricle is no longer able to close completely. Mitral valve regurgitation is the second most common valve defect of adulthood, with an incidence of about 2 to 3 percent.
What is mitral valve regurgitation?
Mitral valve regurgitation occurs when the closing function of the heart valve, located between the left atrium (atrium cordis) and the left ventricle (ventriculus cordis), is so reduced that blood partially flows back out of the ventricle into the atrium during the heartbeat (regurgitation). As a result, a certain amount of blood permanently shuttles back and forth between the left atrium and the ventricle (pendulum volume), with a pendulum volume of 15 percent of the stroke volume or more being considered a relevant mitral valve insufficiency. As a result of this constant pendulum motion of the blood, the ventricle and atrium expand increasingly (dilation), while at the same time the left ventricle becomes more and more restricted in its efficiency (left heart weakness). As a result of the increased blood volume in the left atrium, blood may back up into the lungs. In the long term, the increased blood pressure there (pulmonary hypertension) causes the water in the blood to be forced into the lungs. The right ventricle of the heart is increasingly less able to supply the lungs with blood. This leads to a permanent overload and eventually to right heart failure. Cardiac arrhythmias and atrial fibrillation, blood clots in the affected atrium, decreased exercise capacity, shortness of breath, and edema when the right ventricle is involved are characteristic symptoms of mitral valve regurgitation.
Causes
In most cases, mitral regurgitation is due to rheumatic or bacterial endocarditis. As a result of inflammation of the inner layer of the heart, scar tissue develops that can cause narrowing and leakage of the mitral valve. In addition, rheumatic fever following streptococcal infection can affect the cardiac structures or the mitral valve in addition to the joints and brain, resulting in insufficiency. In addition, mitral valve regurgitation is associated with mitral valve prolapse (malformed mitral valve apparatus), myocardial infarctions (heart attacks), hypertrophic obstructive and dilated cardiomyopathy (heart muscle disease), and calcifications (calcifications) of the valve annulus. Furthermore, mitral valve regurgitation may be congenital or traumatic (rupture of the chordae).
Typical symptoms and signs
- Cardiac arrhythmias
- Heart stuttering and/or palpitations
- Heart murmurs
- Atrial fibrillation
- Thrombosis
- Low resilience
- Shortness of breath
- Edema
Diagnosis and course
Mitral valve regurgitation can be diagnosed by auscultation (listening) with a stethoscope based on audible blood reflux through the affected mitral valve. An ECG (echocardiogram) and an X-ray can reveal characteristic changes in the heart (enlarged left atrium) as well as potential pulmonary edema. In addition, a cardiac catheterization, in which a catheter is advanced to the heart via a major body vein under local anesthesia, can determine the exact pendulum volume and thus the stage of the disease. The prognosis and course of mitral valve regurgitation strongly depend on the severity and degree of progression of the disease. On average, about 25 to 40 percent of affected individuals on whom no surgery was performed are alive after five years from diagnosis, whereas lethality decreases considerably with valve replacement (20-40 percent).
Complications
Mitral valve regurgitation causes serious cardiac symptoms in the patient. These can thereby in the worst case also lead to the death of the patient, if a treatment of this illness is not initiated. As a rule, those affected suffer from heart palpitations or palpitations. Likewise, disturbances of the heart rhythm can occur, so that there are also unusual noises at the heart. Those affected also suffer from fatigue or low exercise tolerance. Furthermore, breathing difficulties may occur, so that loss of consciousness or damage to the internal organs may occur.Without treatment of mitral valve insufficiency, the patient’s life expectancy is significantly reduced. It is not uncommon for affected people to also suffer from depression or often a fear of death when there is an oppressive feeling or a twinge in the chest. The quality of life is significantly reduced by mitral valve insufficiency for this reason. The treatment of this disease depends on the symptoms and the causes. As a rule, however, surgical intervention is necessary, which does not lead to any particular complications. Furthermore, it is usually also necessary to take medication to prevent inflammation and infection.
When should you go to the doctor?
Changes and abnormalities of the heart rhythm should be presented to a doctor as soon as possible. If there are interruptions of the heart rhythm, palpitations or a strong heartbeat, a doctor must be consulted. If audible and unusual heart murmurs occur, there is cause for concern. A visit to the doctor is necessary so that the cause of the symptoms can be determined. A decrease in usual performance, lower emotional as well as physical resilience, and increased fatigability should be investigated and treated. People who suffer from sleep disturbances, experience inner restlessness or a lack of concentration should have a medical check-up. In adulthood, it is also advisable to participate in the medical check-ups offered as a matter of principle for the purpose of early detection of diseases. If shortness of breath develops or anxiety develops due to a decreased oxygen supply, a physician is needed. If thrombosis or edema develops, a doctor’s visit is needed. Irritability, mood swings, and behavioral abnormalities indicate irregularities that should be discussed with a physician. If daily or sporting activities can no longer be carried out, if there is a reduced sense of well-being as well as a withdrawal from participation in social life, a visit to the doctor is recommended. Clarification of the cause is recommended to prevent a life-threatening condition from developing.
Treatment and therapy
Therapeutic measures for mitral valve regurgitation depend on the severity of the disease, although today surgery is generally performed early. Mild heart failure is initially treated with medication. ACE inhibitors, among others, are used to reduce afterload. In parallel, underlying diseases such as arterial hypertension or endocarditis, which promote progression of the insufficiency, are consistently treated. In cases of congenital impairment of the mitral valve apparatus and pronounced mitral valve insufficiency with right heart failure, severely deteriorated functional capacity of the left ventricle, surgical intervention is usually indicated. Standard surgical procedures are mitral valve reconstruction and replacement of the mitral valve with a mechanical or biological valve prosthesis, whereby valve reconstruction is now used more frequently than valve replacement in Germany. In this procedure, the patient is connected to a heart-lung machine while the mitral valve is reconstructed with the help of tissue and synthetic tendon threads (usually made of Goretex) and stabilized by a special support ring sewn onto the mitral valve. If the mitral valve cannot be reconstructed, it is replaced by a prosthetic valve made of synthetic (pyrolytic carbon, stainless steel casing) or biological (bovine or porcine tissue) material. In addition, to prevent blood clots in the dilated left atrium, blood clotting is inhibited with drugs (including phenprocoumon, warfarin). Prophylactically, antibiotic therapy is also used whenever mitral regurgitation is present to prevent bacterial infection and thus additional damage to the valve when there is an increased risk of infection (including dental procedures).
Outlook and prognosis
Because of the highly individual and variable course of mitral valve regurgitation, its prognosis for patients is also relatively variable. Nowadays, however, it is believed that patients who have only mild mitral regurgitation and do not have any other heart disease can have a normal life expectancy.Patients diagnosed and indicated for surgery according to current guidelines have an 89% survival rate over eight years. Studies from 1980 to 1989 show a dependence of the prognosis on the pumping capacity of the left ventricle as it was before surgery. Here, the survival rate of patients with a more normal ventricular function, the so-called ejection fraction of more than 60 percent, for 10 years is about 72 percent. This is thus equivalent to a survival rate of peers without cardiac surgery. Meanwhile, the survival rate of those affected with an ejection fraction of less than 50 percent, at 32 percent, is to be considered significantly lower. Sudden deaths in those with mitral valve regurgitation are quite rare. This is because they only occur with an extremely low frequency of just under 0.8 percent in patients. However, if affected individuals have other heart conditions at the same time, such as atrial fibrillation, sudden deaths can occur with a higher probability of about 4.8 percent.
Prevention
Mitral valve regurgitation can be prevented by consistently treating bacterial infections and other precipitating underlying diseases to reduce the risk of valve impairment. Congenital mitral valve defects leading to insufficiency, on the other hand, cannot be prevented.
Follow-up
After surgical treatment of mitral regurgitation, patients usually recover relatively quickly. Nevertheless, consistent follow-up care is important. For example, the affected person should initially take it easy and take special medications. If mitral valve regurgitation is treated by clipping, the patient still has to spend the night in the intensive care unit. There, the patient’s breathing and cardiovascular system are thoroughly monitored. One day later, the patient is transferred to a normal ward of the hospital, where he stays for about three to five days. During this period, he is already allowed to get up and move around again. It is often noticed in the first few days that the symptoms of mitral valve insufficiency, such as shortness of breath, have improved and the body is able to bear more weight again. Aftercare also includes the use of special medications. For example, the platelet aggression inhibitor clopidogrel, which prevents platelets from clumping together, is administered for about a month. In this way, a blood clot in the arteries can be counteracted. Acetylsalicylic acid can be administered for up to six months. This drug is also a platelet aggression inhibitor, but has a weaker effect than clopidogrel. For about 30 days, the patient should not lift or carry heavy loads. However, light physical endurance training, which can take place in a cardiac exercise group under medical supervision, is quite possible.
Here’s what you can do yourself
In cases of mild to moderate mitral valve insufficiency, situations should be avoided in everyday life that lead to a sudden rise in blood pressure or to sudden increases in peak physical performance demands. A sudden rise in blood pressure due to a surge of adrenaline from the sympathetic nervous system leads to an uncontrollably high pressure load on the two leaflets of the mitral valve, so that during systole the leaflets may bulge into the atrium, increasing the backflow of blood into the left atrium. Endurance sports such as jogging, cycling or swimming help to improve one’s well-being. However, the sport should not be pursued to the respective performance limit. Those affected benefit most from a relatively even load. Individual exercise tolerance can vary greatly depending on the manifestation and severity of the valve insufficiency. The top priority is by no means rest and by no means no sports, but rather self-help in everyday life consists of adapted routines with as few incalculable stress peaks as possible, but definitely with moderate stress. Mental relaxation techniques such as yoga and meditation are also well suited to support any drug treatment with beta blockers and ACE inhibitors. It is helpful to pay a little attention to physical symptoms in everyday life without becoming fixated on them.
