Mitral valve stenosis
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| Mitral valve stenosis |
Mitral valve stenosis is a chronic rheumatic heart disease, leading to one or more attacks of rheumatic fever, which creates rigidity and deformation of the heart valves. The result of this is reflected in the stenosis or regurgitation, and sometimes both. Mitral valves were affected in 50-60% of all cases, lesions associated with mitral and aortic valves are encountered in 20% of all cases, the damage only associated with aortal valves in 10% of all cases. Tricuspid valves are sick with mitral and aortic valves and in 10% of all cases. Pulmonary artery valves are rarely affected.
The clinical picture of mitral valve stenosis
The earliest sign of organic disease of heart valves is expressed murmur, however, the earliest data on the significant hemodynamic valvular damage can be found during the examination with X-ray, fluoroscopy, ECG. In this way we can early detect the increase of coronary sinus. And careful physical findings may be of great benefit in the diagnosis when it comes to heart valve disease.
The procedure for asymptomatic valvular heart disease:
Prevention of mitral valve stenosis.
Renewal of acute rheumatic fever can be prevented.
Avoid exposure to streptococcal infection.
Antibiotic for patients under 35 years of age and those who know they have been exposed to streptococcal infection.
Prompt and adequate treatment for infections caused by hemolytic streptococcus.
Patients should receive advice regarding restoration of teeth, urogenital tract, possible surgery, etc.. In this way it is possible to prevent bacteremia and subacute bacterial endocarditis.
General measures for mitral valve stenosis
The patient have to know about the eventual possibility of reduced physical ability later in life. During the study of patients, changes could be detected in the thyroid gland, they can cause anemia, and arrhythmias, it is necessary to maintain the good health and avoid obesity and excessive physical fatigue.
More than 75% of patients with mitral stenosis are women who were younger than 45 years. Even a relatively small degree of narrowing manifests with certain auscultatory findings. If the valve is narrowed less than 1.5 cm in patients have dyspnea and fatigue. Short diastolic interval during tachycardia is reflected in the lack of ventricular filling. Therefore, the cardiac output is smaller, and the blood is collected in the atrium, pulmonary veins and capillaries. So there is a constant pulmonary congestion, and symptoms are more pronounced. Lying down during the night leads to a further increase of blood volume in the lungs, paroxysmal nocturnal dyspnea, or to transudation fluid in pulmonary alveoli and acute pulmonary edema. It can also occur in severe pulmonary congestion due to acute bronchitis or acute respiratory infection, due to the occurrence of subacute bacterial endocarditis or acute rheumatic carditis. As a result of long-term pulmonary venous pressure there is the opening of anastomosis between the pulmonary and bronchial veins in the form of bronchial submucosal varices.
Fifty to 80% of patients have paroxysmal or chronic atrial fibrillation, which can accelerate the occurrence of dyspnea and pulmonary edema. As a result of thrombus formation in the left atrium. Twenty to 30% of patients in the later period have embolism of cerebral, visceral and peripheral arteries.
In 40-50% of patients have right ventricular hypertrophy, dilatation and decompensation. This leads to the typical signs of right heart decompensation.
In some patients, far unknown reasons, pulmonary arterioles constrict and reduce and in this way they increase the pressure in the pulmonary artery and speeds up the development of right heart decompensation. These patients have easy dyspnea, because less pronounced cardiac output, they are used to fatigue and weakness on exertion.
Treatment for mitral valve stenosis
Closed valvulotome of mitral valve is recommended only in cases where the symptoms are caused by mechanical obstruction of the mitral valve and not because of mitral insufficiency. Mitral valve replacement is recommended in cases of stenosis and regurgitation. If there are signs of mitral stenosis without systolic murmur, it is hard to believe that there are signs of mitral regurgitation. On ECG hypertension and aortic valve lesions were accompanied by signs of left ventricular hypertrophy, but mitral stenosis have the same signs. However, if on the top of the heart there is a moderate systolic murmur, the diagnosis depends on the interpretation of the overall findings.
Special diagnostic analysis can be useful in difficult cases. These include: angiocardiography, dye dilution curve, left ventricular catheterization and left ventricular curve tracer or left ventricular failure. Surgical intervention is not recommended for moderately severe cases, where there is only light exertional dyspnea and fatigue. This is because the cause of mitral stenosis is very different, and because of significant mortality (3-5%) as well as the frequency of the re-creation of stenosis.
Prognosis for mitral valve stenosis
Repeated rheumatic fever may at any time cause fatal cardiac decompensation. Constant threat is manifested in the possibility of developing bacterial endocarditis.
In general, patients with severe mitral stenosis die of heart failure, in the thirties and forties, and after a long period of general incompetence.