The prolapse of the mitral valve of the heart - Causes, symptoms and treatment. MF.
Mitral valve prolapse is one of the innate features of the heart structure. To make it easier to understand what exactly this feature is, let us briefly consider some of the nuances of anatomy and physiology of the heart.
So, the heart is a muscular organ, the function of which is the pumping of blood through the body. The heart consists of two atria and two ventricles. Between the atria and ventricles are located the valves of the heart, tricuspid( tri-fold) on the right and mitral( bivalve) to the left. Valves consist of connective tissue and look like a kind of door that closes the aperture between the atria and the ventricles so that the blood moves in the right direction - normally the blood moves from the atria to the ventricles, there should not be a reverse cast into the atrium. At the time of the expulsion of blood from the atrium into the ventricle( systole of the atria), the valve is open, but as soon as all the blood has entered the ventricle, the valve flaps are closed, and further blood is expelled from the ventricles into the pulmonary artery and the aorta( ventricular systole).
From left to right: 1. The common diastole of the heart - the atria and the ventricles are relaxed;2. Atrial systole - the atria are contracted, the ventricles are relaxed;3. Ventricular systole - the atria are relaxed, the ventricles are shortened.
If the valves of the mitral valve do not fully close during the expulsion of blood from the ventricle into the aorta, then it is said to be prolapse( sagging) into the cavity of the left atrium at the time of systole( contraction of the left ventricle).
The prolapse of the mitral valve is a violation of its connective tissue structure, resulting in incomplete closure of the valves, as a result of which the blood can be thrown back to the atrium( regurgitation).Distinguish congenital( primary) and developed on the background of endocarditis, myocarditis, chest injuries with rupture of chords, heart defects, myocardial infarction( secondary) prolapse. Primary prolapse occurs in about 20 - 40% of healthy people and in most cases does not have a significant effect on the functions of the cardiovascular system.
In modern medicine, the primary prolapse of the mitral valve is considered to be a congenital peculiarity of the heart structure rather than a serious pathology, provided it does not combine with gross developmental malformations and does not cause significant violations of hemodynamics( cardiovascular functions).
Causes of prolapse of the mitral valve
Below we will talk about the primary prolapse of the mitral valve, which refers to small anomalies in the development of the heart. What can cause this anomaly? The main cause of the development of the disease is genetically caused impairment of the synthesis of type 111 collagen. It is a protein that takes part in the formation of connective tissue in all organs, including the heart. In case of a violation of its formation, the connective tissue "skeleton" of the valve loses its strength, the valve becomes loose, softer, so it can not provide sufficient resistance to blood pressure in the cavity of the left ventricle, which leads to the sagging of its valves to the left atrium.
It is also necessary to take into account and harmful factors affecting the development of the fetus and connective tissue during pregnancy - smoking, alcohol, narcotic and toxic substances, occupational hazards, poor nutrition, stress.
Symptoms and signs of mitral valve prolapse
As a rule, the diagnosis is established during the planned screening of newborns, including the method of echocardiography( ultrasound of the heart).
The mitral valve prolapse is classified according to the degree of regurgitation( return of blood), determined with the help of a heart disease with doppler. The following degrees are distinguished:
- 1 degree - the return flow of blood in the left atrium remains at the valve leaf level;
- 2nd degree - blood stream returns to half of the atria;
- 3 degree - a reverse return of blood fills the entire atrium.
If a patient has congenital prolapse, then as a rule, regurgitation is insignificant( grade 1), or there is none at all. If valve prolapse is secondary, then hemodynamically significant regurgitation can develop, since the return of blood to the atrium has a negative effect on the function of the heart and lungs.
With prolapse without regurgitation, there are no clinical symptoms. Like other small heart anomalies( an additional chord, an open oval window), it is possible to suspect this disease only on the basis of a planned examination of the child and the ECHO-CG, which in recent years is a mandatory method of examining all children aged 1 month.
If the disease is accompanied by regurgitation, then with psychoemotional or physical exertion, complaints can arise about spilled pains in the heart, feelings of heart failure, a feeling of "fading" of the heart, shortness of breath, a feeling of lack of air. Since the activity of the heart and the autonomic nervous system( part of the nervous system responsible for the functions of internal organs) is inextricably linked, the patient may be disturbed by dizziness, fainting, nausea, "lump in throat", fatigue, unmotivated weakness, excessive sweating, tachycardia), a slight increase in temperature. All these are symptoms of vegetative crises, which are especially pronounced in a child with prolapse during adolescence, when there is rapid growth and hormonal changes in the body.
In rare cases, when there is a regurgitation of the third degree, the manifestations characteristic of hemodynamic disorders in the heart and lungs - pain in the heart and dyspnea with ordinary household activity, walking, climbing the stairs due to blood stasis in these organs are added to the above described complaints. Also, cardiac arrhythmias - sinus tachycardia, atrial fibrillation and flutter, atrial and ventricular extrasystole, PQ shortened syndrome can rarely be associated. It must be remembered that sometimes regurgitation can progress, that is, the degree of prolapse increases.
Diagnosis of mitral valve prolapse
What is the basis for the diagnosis? The prolapse of the mitral valve can be suspected even during the clinical examination of the child. In small children, prolapse may be accompanied by umbilical and inguinal hernia, hip dysplasia( congenital subluxation and dislocation of the hip).When examining children and adolescents draws attention to the appearance of the patient - high growth, long fingers, long limbs, pathological mobility of the joints, curvature of the spine, deformation of the chest.
When auscultation( listening), either isolated systolic noises and clicks( caused by the tension of the tendon chords during prolapse of the valve at the moment of its closure) or their combination are heard.
The main diagnostic method is echocardiography( ultrasound of the heart) with Doppler study( allows to display the echo signal from moving blood structures).Direct ultrasound can assess the presence of valve prolapse and the degree of its sagging, and Doppler reveals the presence and extent of regurgitation.
In addition, an ECG and 24-hour ECG monitoring are required to determine rhythm and conduction abnormalities( cardiac arrhythmias).
Also shown is chest radiographs to determine whether the heart shadow is widened in diameter and whether there is stagnation of blood in the vessels of the lungs, which may indicate the development of heart failure.
If necessary, samples are taken with a load( treadmill test - walking on a treadmill, bicycle ergometry).
Treatment of mitral valve prolapse
In the event that mitral valve prolapse is not accompanied by clinical symptoms, the patient is not prescribed medication. In hospitalization in the hospital is also not necessary. It shows the implementation of a number of general strengthening measures and observation by a cardiologist with the annual ECHO-KG.
To fortifying activities include: good nutrition, a rational mode of work and rest with sufficient sleep, walking outdoors, general tempering of the body, moderate exercise( allowed by a doctor).
In cases of vegetative - vascular dystonia( vegetative crisis), spinal massage, physiotherapy exercises, electrophoresis with magnesium preparations on the collar zone are prescribed. Vegetative sedative preparations( motherwort, valerian, sage, hawthorn, Ledum), as well as preparations that improve the nutrition of the heart muscle( magneroth, carnitine, riboxin, panangin) and vitamins are shown.
With pronounced feelings of heart failure, and even more so with ECG-confirmed rhythm disturbances, adrenoblockers( carvedilol, bisoprolol, atenolol, anaprilin, etc.) are prescribed
In rare cases( with the development of heart failure, arrhythmias, progressive insufficiency of the mitral valve), surgical correction of prolapse can be performed. Surgical methods of treatment include reconstructive operations on the valve( suturing its sagging flap, shortening the stretched chord) or prosthetics of the valve, replacing it with an artificial one. Surgical treatment of isolated congenital prolapse is used extremely rarely due to the favorable course of this pathology.
Complications of mitral valve prolapse
Are complications possible? Despite the fact that in most cases mitral valve prolapse with minor regurgitation occurs, which does not require special therapy, nevertheless there is a risk of complications development. Complications are rare( only 2-4%) and include the following life threatening conditions requiring treatment in a specialized hospital:
- acute mitral insufficiency is a condition that usually occurs as a result of tearing of the tendon chords in chest injuries. It is characterized by the formation of a "dangling" valve, that is, the valve is not supported by chords, and its leaves are in free movement, not performing their functions. Clinically there is a picture of pulmonary edema - pronounced dyspnea at rest, especially when lying down;forced sitting position( orthopnea), bubbling breath;stagnation wheezing in the lungs.
- bacterial endocarditis is a disease in which microorganisms that break into the blood from a foci of infection in the human body settle on the inner wall of the heart. Most often, endocarditis with valvular disease develops after angina in children, and the presence of initially altered valves may serve as an additional factor in the development of this disease. Two to three weeks after the infection, the patient develops a second fever, chills, a rash, an enlargement of the spleen, and cyanosis( blue skin color).This is a serious disease that leads to the development of heart defects, rough deformation of the heart valves with violation of the functions of the cardiovascular system. Prevention of bacterial endocarditis is the timely sanation of acute and chronic foci of infection( carious teeth, diseases of the ENT - organs - adenoids, chronic inflammation of the tonsils), as well as preventive antibiotics in such procedures as extraction of the tooth, removal of tonsils.
- sudden cardiac death is a formidable complication, apparently due to the onset of idiopathic( sudden, causeless) ventricular fibrillation, which refers to fatal rhythm disturbances.
Prognosis for mitral valve prolapse
Prognosis for life is favorable. Complications are rare, and the patient's quality of life does not suffer. Nevertheless, the patient is not allowed to practice some sports( jumping, karate), as well as professions that cause overload of the cardiovascular system( divers, pilots).
Regarding the service in the army, it can be said that according to orders, the validity for military service is decided individually for each patient on the military medical commission. So, if the young man has a mitral valve prolapse without regurgitation or with a regurgitation of 1 degree, then the patient is fit for service. If there is a regurgitation of 2 degrees, then the patient is fit for condition( in peacetime it will not be called).In the presence of regurgitation of the 3rd degree, violations of rhythm or heart failure of the functional class 11 and above, military service is contraindicated. Thus, most often a patient with mitral valve prolapse with a favorable course and in the absence of complications can serve in the army.
Doctor therapist Sazykina O.Yu.