Mitral insufficiency( mitral valve insufficiency) - Causes, symptoms and treatment. MF.
Jun 07, 2018
Causes and symptoms
Treatment of mitral insufficiency
Mitral insufficiency refers to acquired heart defects and is characterized by lesion of the valves of the mitral( two-leaf) valve.
The mitral valve consists of a connective tissue and is located in the fibrous ring, covering the atrioventricular orifice between the left atrium and the ventricle. Normally, when the blood is released from the left ventricle into the aorta, its valves completely close, preventing the reverse flow of blood into the atrium. The mobility and flexibility of the valves are provided by tendon chords - strands that originate from the inner wall of the ventricle from the papillary( papillary) muscles and attach to the valves, supporting them.
In the case of organic( inflammatory, traumatic, necrotic) lesion of the connective tissue of the valve flaps, tendon chords or papillary muscles, their shape and structure change, resulting in the flaps no longer fit tightly together and between them a space is formed that lets the blood back to the atrium(regurgitation is a condition that has a negative effect on the walls of the auricle).Such a pathology of the valve is called insufficiency.
Mitral valve insufficiency is a disease that occurs as a result of organic damage to the heart, during which there are violations of hemodynamics( blood flow in the heart and in other organs) and develops severe heart failure. This disease in combination with stenosis of the mitral valve is the most common among the acquired heart defects. At the same time, isolated, so-called "pure" mitral insufficiency is rare - only 2% of all acquired vices.
Causes of mitral insufficiency
In 75% of cases the cause of failure is rheumatic fever, especially repeated rheumatic attacks, in other cases, lead to bacterial endocarditis, atherosclerosis. Extremely seldom acute mitral insufficiency can cause acute myocardial infarction, traumas of the heart with lesion of papillary muscles and rupture of tendon chords.
Symptoms of mitral insufficiency
The degree of manifestation of symptoms of a defect depends on the clinical stage of the disease.
In the stage of compensation for , which can last several years, and sometimes even decades, symptoms are usually absent. The patient may be disturbed by increased fatigue, weakness, chilliness and cold extremities.
With progression of changes in the valve flaps, as well as in repeated rheumatic attacks, compensatory mechanisms in the heart are not enough, so comes in the subcompensation stage. During physical exertion, for example, during long and fast walking over long distances, active climbing the stairs, shortness of breath, pain in the left side of the chest, rapid heart rate( tachycardia), heart failure, heart rhythm disturbances( most often atrial fibrillation).In the same period, the patient notices swelling of the feet and legs.
In the late stages of ( stages of decompensation, pronounced decompensation and terminal), complaints take the character of constants and disturb the patient not only with normal household activity, but also at rest. Shortness of breath can be a manifestation of "cardiac" asthma and pulmonary edema - a patient in prone position can not breathe, is in the position of a half-sitting;there are attacks of suffocating cough with possible hemoptysis;edema is observed not only on the limbs, but also throughout the body;the patient is troubled by the heaviness in the right hypochondrium and the increase in the abdomen in volume due to the marked stagnation of blood in the liver. Developing dystrophic changes in the internal organs, as the heart muscle is so depleted that it is not capable of providing blood to tissues and organs of the body.
Diagnosis of mitral insufficiency
In cases where the patient does not notice the presence of complaints from the cardiovascular system, the diagnosis can be established accidentally during a planned medical examination. If the patient seeks a doctor in connection with the above complaints, the diagnosis is established in accordance with the patient's examination data.
Assuming the presence of a rheumatic process with a heart attack, the results of a clinical examination are already possible - complaints and the history of the patient's illness are assessed;when examined, cyanosis is detected( blue fingernails, ears, nose, lips, late stages of the whole face, limbs), edema of the extremities, an enlarged abdomen;with auscultation of the chest, a 1 tone tone is attenuated, systolic murmur at the apex of the heart - at the point of the projection of the mitral valve and stagnant or bubbling( in swelling of the lungs) wheezing in the lungs. In laboratory methods of investigation( general blood and urine tests, biochemical blood analysis, immunological analysis of blood), markers of inflammation, indices of impaired liver and kidney function, indices specific for rheumatism are determined.
The patient is also assigned instrumental research methods: ECG and 24-hour ECG monitoring detects rhythm disturbances, increases( hypertrophy) in the initial stages of the left heart, and then the right;Radiography is prescribed to identify an enlarged shadow of the heart and stagnation of blood in the vessels of the lung tissue, especially with pulmonary edema.
Visualization of anatomical structures of the heart and confirmation of diagnosis is facilitated by echocardiography( ultrasound of the heart).This method allows you to assess the mobility of valve flaps, assess violations of intracardiac blood flow with regurgitation, measure the fraction of regurgitation, pressure in the pulmonary artery, determine the fraction of ejection of blood in the aorta, measure the effective area of the aperture of regurgitation. Depending on these parameters, the mitral valve insufficiency is divided into the following degrees:
- insignificant insufficiency: regurgitation fraction less than 30%( percentage of blood thrown into the left atrium from the volume of blood in the left ventricle at the time of contraction);the area of the hole through which the blood is thrown into the atrium less than 0.2 square meters.cm;the inverse jet of blood in the atrium is located at the valves of the valve and does not reach half of the atrium.
- expressed deficiency: regurgitation fraction 30 - 50%, the area of the regurgitation opening is 0.2 - 0.4 square.cm, a jet of blood fills half the auricle.
- severe failure: , the regurgitation fraction is more than 50%, the opening area is more than 0.4 square meters.cm, a jet of blood fills all the left atrium.
In unexplained cases, and also because of the impossibility of performing an ultrasound of the heart through the anterior thoracic wall, transesophageal echocardiography can be prescribed. To determine the tolerance of exercise, stress-echocardiography is carried out-carrying out ultrasound of the heart before and after samples with physical exertion.
Echocardiography with Doppler examination. In the figure on the right, the arrow indicates the transfer of blood into the left atrium through the mitral valve( MK).
As with mitral stenosis, in intricate clinical situations with controversial examination results or before cardiac surgery, cardiac catheterization can be prescribed to measure the pressure difference in its chambers. If a patient with this defect has ischemic heart disease, the doctor may consider it necessary to perform coronaroangiography( CAG) with the introduction of X-ray contrast material into the coronary( cardiac) vessels and the evaluation of their patency.
Treatment of mitral insufficiency
Treatment of this heart disease involves the appointment of medications and a radical way to cure the blemish - surgical correction of the valve.
In medicamentous treatment, the following groups of drugs are used:
- to reduce the overall peripheral resistance of the vessels, in which the enlarged left ventricle is to be expelled blood, ACE inhibitors and beta-blockers are prescribed: perindopril 2-4 mg once a day, fosinopril 10-40 mg once a day;Carvedilol 12.5 - 25 mg once a day, bisoprolol 5 - 10 mg once a day.
- to reduce the flow of blood to the stretched right atrium, nitrates are prescribed - nitroglycerin preparations and its analogues: nitrospray under the tongue 1 to 3 doses in attacks of dyspnea or chest pain, cardiac 20 to 40 mg 20 minutes before physical exertion at early stages and daily fromone to five times a day in the late stages( with pronounced dyspnea and frequent episodes of pulmonary edema).
- to reduce the total volume of circulating blood and as a result, to exclude bulk heart overload, diuretics( diuretics) are prescribed: indapamide 2.5 mg in the morning, veroshpiron 100 - 200 mg in the morning, etc.
- antiplatelet agents are prescribed to reduce thrombus formation and increased blood clottinganticoagulants: trombo Ass 50 - 100 mg for lunch after meals;Warfarin 2. 5 mg, Plavix 75 mg - the dose is calculated individually under strict control of blood coagulation.
- in the presence of atrial fibrillation, antiarrhythmic drugs are used to help restore the correct rhythm( with paroxysmal form) - polarizing mixture intravenously, amiodarone, novocaineamide IV.With a constant form of atrial fibrillation, cardiac glycosides( korglikon, strophanthin) and beta-blockers are prescribed.
- antibiotics( bicillin, amoxicillin with clavulanic acid, etc.) are used to prevent repeated rheumatic attacks, as well as for invasive( with the introduction into the tissue of the body) interventions.
The treatment regimen is set individually for each patient by the attending physician.
From surgical methods of treatment, the use of valve plastic( lining valve flaps, tendon chords) and its prosthetics.
The figure shows the prosthesis of the valve with a mechanical prosthesis.
The operation is shown at the second degree of the defect( pronounced insufficiency) and in the second - the third stages of the process flow( sub- and decompensation).In the stage of pronounced decompensation, the use of the surgical method of treatment remains controversial due to the severe general condition, and at the terminal stage the operation is strictly contraindicated.
Lifestyle with mitral insufficiency
The patient must follow the general principles of healthy lifestyle, as well as follow the doctor's recommendations, used in many cardiological diseases - exclude alcohol, smoking, fatty, fried, spicy dishes;limit the amount of fluid and salt consumed;sleep a lot and walk more often outdoors.
When a woman becomes pregnant, a woman should be observed by a cardiac surgeon together with an obstetrician and a cardiologist. In early stages and with a severe degree of vice, pregnancy can be preserved, and with severe hemodynamic disorders it is strictly contraindicated. The delivery is most likely to be done by caesarean section.
Complications of mitral insufficiency
Complications without treatment
In cases where the patient is not disturbed by complaints, and the degree of defect determined by ultrasound of the heart is not severe, the lack of taking medications or surgical treatment does not affect the state of hemodynamics. If the patient treats active complaints, and the diagnosis of mitral insufficiency is confirmed or diagnosed his severe degree, the lack of treatment leads to a violation of blood circulation in the body and the functions of the cardiovascular system. Without correction of the cardiac muscle, complications, including life threatening ones, can occur, including cardiogenic shock, pulmonary edema, systemic thromboembolism, and paroxysms of atrial fibrillation, with the risk of blood clots and subsidence in the vessels of the brain, lungs, intestines, heart, and femoral artery. Complications are more rare than with mitral stenosis.
Complications of operation
As with any operation, with prosthetics or mitral valve plastic, there is a certain operational risk. Mortality after such operations, according to different authors, reaches 8 - 20%.Also, the patient may develop postoperative complications, for example, the formation of blood clots in the cavities of the heart, due to the work of mechanical prostheses, the development of bacterial inflammation on the valve flaps, including artificial biological, the formation of adhesions between the valves with the development of narrowing of the valve opening( stenosis).Prevention of complications is the adequate use of anticoagulants, antibiotic therapy in the early postoperative period, as well as during various diagnostic and therapeutic activities in other areas of medicine( catheterization of the bladder, extraction - tooth extraction and other dental procedures, gynecological operations, etc.)..
Even in the absence of complaints from the heart of the patient, the prognosis for life is unfavorable, as the disease progresses with the development of hemodynamic disorders, which, without treatment, lead to severe disruption of the body's functions and to a lethal outcome.
With a timely operation and a competent prescription of drugs, life expectancy increases, as does the quality of life.
Therapist doctor Sazykina O.Yu.