1. Mitral insufficiency

Question 1

Mitral insufficiency definition?

Answer 1

Represents the most frequently occurring acquired valvular defect. It can occur alone or in
combination with mitral stenosis

Question 2

Which parts of valves are afflicted?

Answer 2

• The front or back cusps of the mitral valves - may be deformed in consequence of rheumatic
  carditis. The cusps themselves are usually afflicted also in the so-called prolapse of mitral valve, and
  in an inborn splitting of one of the cusps. At an older age calcification is often present with
  consequently restricted movement of the cusps.
• Fibrous tendons which attach the valves to the papillary muscle – are often calcified or
  coalescent after rheumatic carditis
• Papillary muscle – is often hypofunctional in ischemic heart disease, and infarction may bring
  about its rupture accompanied with huge regurgitation.
• Mitral anulus – is dilated in left ventricular failure. Intact valves with preserved movability do
  not manage to enclose the enlarged mitral orifice and the so-called relative mitral insufficiency
  develops.

Question 3

Functional defect in mitral insufficiency?

Answer 3

The basic functional defect in mitral insufficiency is the backward flowing of the blood from the left
ventricle into the left atrium during ventricular systole. The left atrium is filled with the blood from
the pulmonary veins and, surplus, it is filled also with the blood from the left ventricle
During the ventricular diastole the left ventricle
ventricle receives blood, the amount of which is increased by the volume which had escaped into the
left atrium during the systole.

Question 4

During ventricular systole blood flows in?

Answer 4

During the ventricular systole the blood flows in two directions. The insufficient mitral valve lets the
excessive amount of blood to regurgitate into the left atrium and the periphery receives a normal
amount of blood. The volume which in consequence of mitral insufficiency returns into the left
atrium moves in a pendulous manner between the left atrium and ventricle. Volume overload inflicts
both the left atrium and left ventricle.
The above mentioned changes result in an increased amount of blood in the left ventricle at the end
of diastole

Question 5

It determines left ventricular hypertrophy development of volume type which
compensates the presented volume overload:

Answer 5

1. The extent of regurgitation is determined foremostly by anatomical changes in the mitral
   valve. Aside form this the backward blood flow depends upon the pressure in the left ventricle.
2. The state of atrial musculature. Providing the atrial musculature is of optimal elasticity and
   contractile state, the left atrium ”resists” to the excessive delivery of blood by increasing its tonus.
3. The velocity of mitral insufficiency development. Gradual enlargement of mitral regurgitation
   exposes the left atrium to an increased delivery of blood.