Cardiomyopathies

Cardiomyopathies - diseases at which the myocardium lesion is primary process, instead of a consequence of a hypertonia, congenital diseases, lesions of valves, coronal arteries, a pericardium.

Distinguish cardiomyopathies:

  1. With primary involving of a myocardium:
    1. Idiopathic
    2. Family
    3. An unknown aetiology
  2. With secondary involving of a myocardium:
    1. Infectious
    2. Metabolic
    3. Hereditary
    4. Scarce
    5. Diseases of a copulative tissue
    6. Infiltrates and granulomas:
      • an amyloidosis
      • a sarcoidosis
      • cancerous neoplasms
      • a hemochromatosis
    7. Myoneural diseases
    8. Intoxications:
      • alcohol
      • radiation
      • medicinal preparations
    9. The diseases of heart bound to pregnancy

Preferable classification of cardiomyopathies on the basis of differences in their physiopathology and clinical implications is considered:

  1. Dilatation (congestive): augmentation of the left and-or right ventricles, disturbance of systolic function, a congestive heart failure, arrhythmias, embolisms.
  2. Restrictive: an endomyocardial cicatrisation or the infiltration of a myocardium leading to occurrence of an interrupting of filling of the left and-or right ventricles.
  3. Hypertrophic: the dissymmetric hypertrophy of a left ventricle, in typical cases in larger degree is involved a septum, than a free side, with obstruction of outflow tracts from a ventricle or without it; usually at not amplate lumen of a left ventricle.

Dilatation (congestive) cardiomyopathy

To augmentation of the dimensions of heart and appearance of symptoms of a congestive heart failure conducts disturbance of systolic function of heart. Parietal thrombuses, especially in the field of a left ventricle apex are often observed. Histological researches have taped intensive fields of intersticial and perivascular fibrosises. The dilatation cardiomyopathy is a net result of damage of a myocardium various toxic, metabolic or infectious agents.

 

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Clinic

Gradually the ventricular congestive heart failure, showing a dyspnea educes is left - ventricular and the right - at physical exercise, weariness, an orthopnea, a paroxysmal night dyspnea, peripheric edemas and heartbeats. At some patients the left ventricle dilatation exists within months or years before proves clinically.

Physical inspection

Tap various degree of augmentation of heart and a congestive heart failure. At patients with serious forms of disease tap small pulse pressure and the enlarged pressure in bulbar veins. Often meet III and IV warm tints. Can educe a mitral and tricuspid regurgitation.

Diagnostics
  1. Thorax roentgenography - augmentation left a zhelu-daughter, sometimes - a generalised cardiomegaly owing to presence of a concomitant exudate in a pericardium. Signs of a venous hypertensia in lungs and an intersticial alveolar edema.
  2. An electrocardiogram - a sinus tachycardia or an atrial fibrillation, ventricular arrhythmias, signs of augmentation of the left auricle, diffusive nonspecific changes of segment ST and tooth T, sometimes disturbance of intraventricular conductivity.
  3. An echocardiography - left ventricle augmentation at normal or slightly thickened side, systolic dysfunction (the lowered fraction of outlier).
  4. Hemodynamic studying - warm outlier in rest is moderately or considerably lowered and not enlarged at physical exercise. Certainly - a diastolic pressure in a left ventricle, pressure in the left auricle, pressure of jamming in pulmonary capillars are raised.
Treatment

Basically - heart failure treatment; antiarrhytmic therapy (it is cautious since. Treatment of asymptomatic ventricular arrhythmias can lead to oppression of contractile function of ventricles). Constant reception of anticoagulants, since. Parietal thrombuses in cardial cavities are often formed. Immunosuppression therapy by Prednisonum, Azathioprinum if there is an active myocarditis. Surgical treatment (under indications).

Restrictive cardiomyopathy

Distinctive line is a disturbance of diastolic function. Ventricle sides get an appreciable rigidity and interfere with filling of a lumen of a ventricle. The cause are the myocardial fibrosis, a hypertrophy or infiltration of a various inflammatory aetiology (an amyloidosis, a sarcoidosis). The restriction is observed also at a hemochromatosis, glycogen deposits, an endomyocardial fibrosis, a fibroelastosis, eosinophilias, neoplastic infiltration.

Clinic

As a result of constantly enlarged venous pressure such patients usually have edemas, an ascites, the liver strain is enlarged. The venous pressure in bulbar veins is raised, it does not alight to normal value or can be enlarged at an inspiration (Kussmaul's sign). Warm tints can be muffled, are often auscultated III and IV tints. The apical beat is well palpated.

Diagnostics
  1. An electrocardiogram - a low voltage, nonspecific changes ST - T and various arrhythmias.
  2. Thorax roentgenography - signs of stagnation of blood in lungs can be combined with the normal dimensions of heart. Even in serotinal stages of disease when the contractile ability is considerably broken, the complicated filling of the mitral valve interferes with a cardiodiosis.
  3. An echocardiography - a thickening of sides of the left and right ventricles. The combination of a thickening of a side of a left ventricle and depression of a voltage of a ventricular complex on an electrocardiogram is characteristic for a restrictive cardiomyopathy. The dimensions of lumens of the left and right ventricles are not variated, the left and right auricles are enlarged.
  4. A heart catheterization - rising of a filling pressure of the right and left ventricles and a classical curve of pressure of a type "a diastolic dip and a plateau".
  5. An endomyocardial biopsy
Treatment
  1. The general actions include cautious application of diuretics at stagnation in a small and big circle of a circulation and digoxin at depression of contractility of a left ventricle. At an amyloidosis digoxin is contraindicative in connection with the big danger glycoside to an intoxication. In some cases vasodilators are shown, but to apply them it is necessary with guard because of danger of excessive depression of a preload as at a restrictive cardiomyopathy for maintenance adequate warm outlier the high pressure of filling of ventricles is necessary.
  2. Specific therapy is referred on elimination of the cause of a restrictive cardiomyopathy.

Hypertrophic cardiomyopathy

This disease is characterised by a left ventricle hypertrophy, in typical cases without a dilatation, thus there is no obvious aetiology.

Two characteristic signs of disease, but not being the obligatory:

  1. A dissymmetric hypertrophy of a septum at which the top part of an interventricular septum in comparison with thickness sub - a basal free side of a left ventricle is mainly hypertrophied
  2. The complicated outflow of blood from a left ventricle (dynamic obstruction) owing to narrowing of subaortal range.

With a hypertrophic cardiomyopathy disease is inherited from 50 % of patients on an autosomno-dominant type with high degree of a penetrance. The obstruction at a hypertrophic cardiomyopathy (if it is available) has dynamic character, degree of its expression variates at repeated inspections of the patient, variates from one reduction to another. The obstruction grows out of the further narrowing of initially reduced dimension of a bearing tract at the expense of advance of the mitral valve against the hypertrophied septum in a systole (systolic excursion of the valve forward). The dynamic obstruction can be result of 3 basic mechanisms:

  1. The enlarged contractility of a left ventricle that leads to reduction of its systolic volume and augmentation of rate of expulsion of blood through a bearing tract therefore excursion of a forward cusp of the mitral valve aside is observed, inverse to a septum, as consequence of the lowered pressure of a distention
  2. The lowered volume of a ventricle (preload) that leads to the further reduction of the dimensions of a bearing tract
  3. The lowered resistance of a blood flow in an aorta (afterload) that enlarges rate of a blood flow through subaortal range and also reduces systolic volume of a ventricle.

All interventions enlarging contractility of a myocardium as well as reducing volume of a ventricle (Valsalva test), can enlarge obstruction. On the contrary, rising of arterial pressure, augmentation of venous return, circulating blood volume promote augmentation of volume of a ventricle and reduce obstruction.

Clinic

The first clinical implication of disease can be the subitaneous mors to which sick children and teenagers are often subject, is frequent during time or after physical exercise. Clinical implications of a stenocardia: a dyspnea arising in basic owing to the reduction of elasticity of sides of a left ventricle that leads to disturbance of filling of a left ventricle and diastolic pressure augmentation in it, and also to pressure augmentation in the left auricle.

Stenocardia

The stenocardia - in most cases a pain is atypical, can appear in rest and the cause - depression of a coronary blood flow that allows to assume an ischemia, weariness, a syncope (the complaint to appearance of a grey veil before eyes) is not always connected to physical exercise.

At the majority of patients with obstruction - the double or triad apical beat, quickly increasing sphygmus on carotid arteries (peak and a dome) and additional IV warm tint.

Distinctive feature - presence of systolic hum of the rhomboidal form, which character in typical cases rasping; it is auscultated through an appreciable interspace after I warm tint in the inferior part of a breast bone, to the left of it, and also in the field of an apex more often. In the field of an apex hum in larger degree holosystolic, and blowing, reflecting a mitral regurgitation.

Syncopes - after physical exercise as result of reduction of the dimensions of a left ventricle and obstruction intensifying.

Diagnostics
  1. An electrocardiogram - a left ventricle hypertrophy, nonspecific changes ST and T, and also augmentation of the left auricle.
  2. An echocardiography - at an azygomorphous hypertrophy of a septum without obstruction an interrelation of a thickness of a septum at a thickness of a side of a ventricle 1,3 and more. At the obstructive form of disease define systolic shift of a forward cusp of the mitral valve, a systolic tremor of cusps of the aortal valve and its early closure corresponding with peaks and domes on record of carotid sphygmus.
  3. A heart catheterization
Treatment

Therapy is referred on depression of expression of clinical symptoms.

Medicamental therapy
  1. B - blockers (propranolol) effectively reduce expression of symptoms.
    • blockage b - receptors slows down a rhythm of warm reductions that enlarges filling of a left ventricle and its dimensions, reducing obstruction.
    • b - blockers, reducing energy of warm reductions, reduce rate of a krovo-current, that also promotes obstruction reduction.
  2. Blockers Ca - canals
    • enrich working capacity of a left ventricle and reduce an intraventricular pressure gradient
    • widely apply verapamil
  3. Warm glycosides are contraindicative, if the obstruction is expressed and the left ventricle lumen as warm glycosides enlarge force of warm reductions that enhances obstruction is small.

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