heart valves
Synonym: Valvae cordis
definition
The heart consists of four cavities, which are separated from each other and from the respective executing blood vessels by a total of four heart valves. This enables blood to flow in only one direction and only if it occurs as part of the heart's action (Systole or diastole) makes sense.
One differentiates the heart valves in two leaflet valves from two pocket valves.
Figure heart valves
- Tricuspid valve -
Tricuspid valva - Mitral valve -
Valva mitralis - Aortic valve -
Valva aortae - Pulmonary valve -
Valva trunci pulmonalis - Right atrial -
Atrium dextrum - Right ventricle -
Ventriculus dexter - Left atrium -
Atrium sinistrum - Left ventricle -
Ventriculus sinister - Papillary muscle -
Papillary muscle - Superior vena cava -
Superior vena cava - Aortic arch - Arcus aortae
- Pulmonary artery trunk -
Pulmonary trunk
1 + 2 sail flaps
= Atrial clamp valves
= Atrioventricular valves
= AV valves
3 + 4 pocket flaps
You can find an overview of all Dr-Gumpert images at: medical illustrations
Anatomy and function
The heart valves are in the so-called Heart skeleton, a fiberboard between Forecourt and chamber, anchored. They are protuberances of the Endocards, i.e. the innermost layer of the heart wall and ensure that the One way blood only (unidirectional) by the heart can flow. Besides, they let you Blood flow only at certain times the heart action too. they also Function heart.
One differentiates between two Sail flaps (Valvae cuspidales) and two Pocket flaps (Valvae semilunares). The Sail flaps are also called Atrioventricular valves (AV valves) because they are between atrium (Atrium) and chamber (Ventricle) are located. The naming of the heart valves is based on the respective number of leaflets.
- The Tricuspid valve is the AV valve between right atrium and ventricles. (tri- three, cuspis- sails)
- The Bicuspid valve (bi - two, cuspis - sails), also called Mitral valve is located between the left atrium and the ventricle.
The additional designation of the bicuspid valve as a mitral valve comes from the fact that it has one with its two leaflets Bishop's cap (miter) is similar.
The AV valves preventthat during systole, in which the ventricle tenses, Blood back from the chamber to the atrium flows. The sail flaps are over Tendon threads (Chordae tendineae) with the Papillary muscles connected. These are anchored in the wall of the heart chamber and ensure that the valves do not recoil too far into the atrium when they close and during the tension phase.
The two Pocket flaps or Semilunar valves are respectively between the ventricle and the evacuating vessel.
- In the right heart it is Pulmonary valvethat between right ventricle and Pulmonary trunk (i.e. the beginning of the pulmonary circulation).
- In the left heart they separate Aortic valve the left ventricle from the main artery.
Consequently prevent the pocket flaps den Return of blood from the two large vessels to the chambers after the systole has ended.
Their Names they have therefore that they are out 3 crescent-shaped each (semilunaris - crescent-shaped) Bulges or pockets.
Heart action and heart sounds
The heart action can be in diastole (Relaxation and filling phase) and Systole (Tension and expulsion phase) subdivide.
- in the first part (Diastole) the heart muscle relaxes and the atria fill with blood. At the same time, both the valves between atrium and ventricle (AV valves) and the valves between the chambers and draining vessels (semilunar valves) are closed.
- Then open the second part of diastole the AV valves (Bicuspid and Tricuspid valve) and the Filling the chambers with blood takes place.
- The begins with the contraction (tension) of the ventricular muscles Systole, with the AV valves initially closing to prevent backflow into the atrium.
- Then open the pocket flaps (Pulmonary and Aortic valve) and the blood is in the Lungs- or. Body circulation pumped. When the pocket flaps are closed, the diastole begins again.
It was previously believed that the closure of the AV valves at the onset of systole was the first of the two Heart sounds would generate. However, it is now widely accepted that the 1. Heart sound only after the end of the AV valves, namely through the Tension of the ventricular muscles comes about.
Of the 2. Heart sound however, is actually a Key closing tone. It arises from the End of the pocket flaps at the end of the systole, i.e. after the blood from the ventricles into the Lungs- or body circulation has been ejected.
Clinical aspects of the heart valves
Is the Function of a heart valve restrictedso this is called Heart valve vitium designated.
Such a Vitium can congenital or acquired be. A distinction is made between two types of functional restrictions:
- At a Valve stenosis can shut the flap no longer open completely, less blood gets through it.
Valve stenosis leads to one increased pressure load of the heart and thus to one Wall thickening of the section in front of the affected valve (concentric hypertrophy). - At a Valve insufficiency no longer closes the affected valve properly, blood flows back into the heart area in front of the valve.
With valve insufficiency, there is one Volume loading of the section in front of the flap through constant blood reflux. This also results in a thickening of the wall, albeit with a simultaneous expansion of the heart cavity (eccentric hypertrophy).
Slight valve defects can unnoticed stay, higher grade become usually symptomatic sooner or later.
Common to all valve defects is then the Exertional dyspnea (Difficulty breathing sometimes even with low physical exertion).
Most commonly affected are the Valves of the left heart, so the Mitral valve and the Aortic valve.
Read more about the topic here: Valvular heart disease
