The aortic valve insufficiency

  • Clinic
  • Electrocardiographic study
  • Phonocardiographic study
  • Polycardiography study
  • X-ray examination
  • Classification
  • Diagnosis and differential diagnosis
  • Forecast
  • The pathogenesis of disorders of blood circulation.
    At insufficiency of the aortic valve as a result, infringed its functions are part of blood from the aorta during diastole is returned in the left ventricle. Circulatory disorders when this evil depend largely on the degree of damage to the valve and the condition of the heart muscle. The severity of the defect is in direct dependence on blood volume that is returned in the left ventricle during diastole. A number of patients regurgitation (reverse current of blood) reaches 60-70% of the stroke volume (G. I. Golikov, 1968).
    The value regurgitation depends on the area uncovered part of the aortic holes, duration diastole and differential pressure in the left ventricle and the aorta in the last phase.
    Nerezko expressed lack aortic valve does not cause significant hemodynamic changes. Severe aortic insufficiency has a significant pathological effect on hemodynamics. During diastole under the action of blood pressure from the aorta through the damaged valve of the blood back into the left ventricle, which during diastole receives blood from the left atrium; therefore, it increased diastolic filling.
    This increase of blood flow leads to expansion of the left ventricular cavity, is developing "Tonawanda" or "adaptive" dilation of the heart (centuries Parin, F. 3. Meyerson, 1965).
    Due to the increased diastolic filling is greater than normal, stretching the muscles of the left ventricle, and this according to the law Frank-Sterling increases the force of contraction, resulting in the left ventricle during systole throws in the aorta increased compared with normal blood volume, consisting of blood volume received in the left ventricle of the left ventricle and the aorta. Develops systolicdiastolic overload of the left ventricle.
    Increased work of the left ventricle quickly leads to hypertrophy of the myocardium. Muscle fibers of the left ventricle lengthen and thicken, there is an increase of cores. It helps to normalize the function of the heart.
    Thus, the flaw is compensated by muscle hypertrophy of the left ventricle and expand its cavity. At this stage of development blemish in compensation takes part only of the left ventricle, which due to the presence of aortic insufficiency have to do extra work.
    At insufficiency of the aortic valve changing of the phase structure of left ventricular systole. The initial pressure increases, the phase of isometric contraction in severe aortic insufficiency is shortened, and the phase exile lengthened the duration of the entire beats increases. Such a change in the phase structure of systolic left ventricular allows the ventricle to throw during systole in the aorta is the large amount of blood.
    The increase in stroke volume of the left ventricle increases in systolic blood pressure in the aorta and peripheral arteries. Increases and the amplitude of pressure in the aorta. After a sharp rise during systole, during diastole declines in the back flow of blood from the aorta to the left ventricle. The reduction of diastolic blood pressure in the aorta in aortic insufficiency is due not only to reverse the flow of blood through the valve defect, and reduced resistance of the vascular bed (F. 3. Meyerson, 1968). The decrease in end-diastolic pressure in the aorta facilitates receiving a large amount of blood during left ventricular systole.
    Due to the large reserve possibilities of the left ventricle period of compensation in aortic insufficiency may continue for a long time.
    With the weakening of the power of the muscle contraction of the left ventricle, which is usually observed at the progression of the rheumatic process, or when excessive exercise, infections, intoxications, by early diastole in the left jeludocke the number of "residual" blood, thereby increasing diastolic pressure in the left ventricle, which makes emptying the left atrium. The left atrium expands, pressure increases, thereby increasing the pressure and develop congestion in the vessels of the small circle of blood circulation.
    The increase of pressure vessels in the small circle supported enhanced work right ventricle, making for some time still provided compensation blemish. It is already past the stage of compensation, which quickly comes decompensation, characterized myogenic dilation of the left and then the right ventricle.
    Decompensation in aortic insufficiency is manifested at first mainly in the form of failure left heart, develop congestion in the lungs until the swelling of the lungs, later joined by the phenomenon of lack of right parts of the heart in the form of stagnation in the big circulation.
    Sometimes when aortic insufficiency after heavy exercise may develop acute failure of the left ventricle.