Muscular heart wall layer. Flat multilayer wall

31.03.2020

It is he who protects our engine from injuries, the penetration of infections, carefully fixes the heart in a certain position in the chest cavity, preventing its displacement. Let's talk more about the structure and functions of the outer layer or pericardia.

1 Cardiac layers

The heart has 3 layers or shells. The middle layer is muscular, or myocardium, (on the Latvian prefix myo- means "muscle"), the fattest and dense. The middle layer provides contractile work, this layer is a true working, the basis of our "motor", it represents the main part of the body. Myocardium is represented by a cross-striped cardiac tissue, endowed with special, characteristic of it only with functions: the ability to spontaneously excite and transmit a pulse to other heart departments on a conductive system.

Another important difference of myocardium from the muscles of the skeleton is that its cells are not multicellular, but have one core and represent a network. The survey of the upper and lower heart cavities is separated by the horizontal and vertical partitions of the fibrous structure, these partitions provide the possibility of a separate reduction in atrial and ventricles. Muscular Heart Shell is the basis of the organ. Muscular fibers are organized in bundles, a two-layer structure is isolated in the upper chambers of the heart: the beams of the outer layer and internal.

Muscular heart sheath

A distinctive feature of the ventricular myocardium is that in addition to muscle beams of the surface layer and internal beams, there is still an average layer - separate bundles for each ventricular ring structure. The inner sheath of the heart or endocardia (on the Latvian prefix EndO- means "internal") - thin, thick in one cell epithelial layer. It sweels the inner surface of the heart, all of its cameras from the inside, and from the double layer of endocardium, heart valves consist.

In structure, the inner shell of the heart is very similar to the inner layer of blood vessels, blood is facing the layer when passing through the cameras. It is important that this layer is smooth, in order to avoid thrombosis that can be formed during the destruction of blood cells from colliding on heart walls. This does not happen in a healthy body, since endocard has an ideally smooth surface. The outer surface of the heart is pericardium. This layer is represented by an external leaflet of fibrous structure and internal - serous. Between the sheets of the surface layer is the cavity - pericardial, with a small amount of liquid.

2 Delete into the outer layer

Structure of the wall of the heart

So, pericardium is not a single outer heart layer at all, but a layer consisting of several plates: fibrous and serous. Fibrosis pericard dense, outdoor. It performs a greater degree protective function and the function of some fixation of the organ in the chest cavity. And the inner, serous layer is firmly adjacent directly to myocardium, this inner layer is called epicardium. Imagine a bag with a double bottom? Approximately the external and internal pericardial leaves look like this.

The gap between them is the pericardial cavity, it is normal that it contains from 2 to 35 milliliters of serous fluid. Liquid is needed for a softer friction of the layer of each other. Epicard tightly covers the outer layer of myocardium, as well as the initial departments of the largest blood vessels, its other name is visceral pericard (Latin Viscera- organs, insides), i.e. This is a layer lining the heart directly. And already parietal pericardium - the most none of the outer layer of all heart shells.

The following departments or walls in the surface pericardial layer are distinguished, their name depends directly from the organs and sections to which the shell arrive. Pericarda walls:

Pericard front wall. Goes to the chest wall
Diaphragm wall. Directly fasten with a diaphragm This wall of the shell.
Side or pleural. It is isolated on the sides of the mediastinum, fit to the Light Plegre.
Rear. It borders with the esophagus, downward aorta.

The anatomical structure of this shell of the heart is not simple, because in addition to the walls, there are also sinuses in the pericardia. These are such physiological cavities, we will not delve into their structure. It is enough just to know that one of these pericardial sinuses is located between the sternum and the diaphragm. It is it, in pathological conditions, pierce or punctate health workers. This diagnostic manipulation is high-tech and complex, is carried out by specially trained personnel, often under ultrasound control.

3 Why the heart of the bag?

Pericard and its structure

Our main engine "The body requires extremely careful attitude and care. Probably, for this purpose, Nature has a heart in the bag - Pericard. First of all, it performs the function of protection, carefully covered the heart into his shells. Also, the necroserous bag fixes, fixes our "motor" in the mediastinum, preventing the displacement when driving. This is possible due to the durable fixation of the heart surface using bundles to the diaphragm, breast, vertebrae.

It should be noted the role of pericardia as a barrier for heart fabrics from various infections. Pericardary "segreases" our "motor" from other chest organs, clearly determining the position of the heart and helping the cardiac cameras better fill in blood. At the same time, the surface layer prevents the extension of the organ due to the sudden overload. Preventing interpretation of chambers is another important role of the outer wall of the heart.

4 When "sick" Pericard

Pericarditis - Inflammation of the Owl Bag

Inflammation of the outer shell of the heart is called pericarditis. The reasons of the inflammatory process can be infectious agents: viruses, bacteria, mushrooms. Also provoke this pathology can injury chest, directly heart pathology, for example, acute heart attack. Also, the exacerbation of such systemic diseases as SD, rheumatoid arthritis, can serve as the beginning in the chain of inflammatory phenomena of the surface heart layer.

Not rare pericarditis accompanies mediastinal tumor processes. Depending on whether many liquid is released into the pericardial cavity during inflammation, they allocate dry and discharge form of the disease. Often these forms are precisely in such a manner with each other with the course and progression of the disease. Dry cough, pain in chest, especially with a deep breath, changing the position of the body, during cough is characteristic of dry form of the disease.

The discharge form is characterized by a certain decrease in pain sharpness, and the same time appears the sad severity, shortness of breath, progressive weakness. With proven population in the cavity of the pericardia, the heart turns out to be siled in vice, a normal ability to reduce is lost. Dyspnea pursues the patient even alone, active movements become and not possible at all. The risk of tamponade of the heart is growing, which threatens with a fatal outcome.

5 injection in heart or pericardial puncture

This manipulation can be carried out both with the diagnostic goal and with therapeutic. The doctor conducts puncture in the threat of tamponades, with significant disposal when it is necessary to pump the liquid from the heart bag, thereby providing the authority to reduce. With the diagnostic purpose, puncture is performed to clarify etiology or causes of inflammation. This manipulation is very complex and requires a high qualification of the doctor, since it has a risk of damage to the heart.

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Heart cameras

These heart departments are divided by partitions, between the chambers the blood circulates through the valve apparatus.

The walls of the atrium are quite thin - this is due to the fact that when the muscle tissue is reduced, they have to overcome much less resistance, rather than ventricles.

The walls of the ventricles are at times thicker - this is due to the fact that it is due to the efforts of muscle tissue of this heart pressure in a small and large circulation of blood circulation reaches high values \u200b\u200band provides a continuous blood flow.

Valve apparatus

2 atrial ventricular valve ( according to the logic of the name it is clear that these valves separate atrium from ventricles)
one pulp of the pulmonary barrel ( through which blood moves from the heart to the circulatory system of the lung)
one aortic valve (this valve separates the aorta cavity from the left ventricular cavity.).

The valve apparatus of the heart is not universal - the valves have a different structure, size and purpose.

Layers of a heart wall

1. Outer mucosa layer - Pericard. This layer provides a gliding heart when working inside the cardiac bag. It is thanks to this layer, the heart does not bother with his movements.

Some of the information about the hydrodynamics of the heart

Heart Reduction Phase

How does the heart bustling?

What does the heart work?

Further, the excitement covers the muscle tissue of the ventricles - there is a synchronous reduction of the walls of the ventricles. The pressure inside the chambers increases, which leads to the slamming of the atrocading valves and at the same time to open the aortic and pulmonary valve. In this case, the blood continues its unidirectional movement towards the pulmonary fabric and the rest of the authorities.

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Structure of the walls of the heart

Heart walls consist of three layers:

endocardium - thin inner layer;
myocardium - fat muscular layer;
epicard is a thin outer layer, which is a visceral leaf of pericardia - a serous heart sheath (cardiac bag).

Endocard wore the heart cavity from the inside, just repeating her complex relief. An endocardium is formed by one layer of flat polygonal endotheliocytes located on a fine basal membrane.

Myocardium is formed by a cardiac cross-striped muscle tissue and consists of hearty myocytes interconnected by a large number of jumpers with which they are associated with muscle complexes that form a narrow-natal network. Such a muscular network provides a rhythmic reduction in atria and ventricles. At the atria, the thickness of myocardium is the smallest; The left ventricle has the greatest.

Atrial myocardium is separated by fibrous rings from the myocardium of ventricles. The synchronization of myocardial cuts provides a conductive heart system, one for atria and ventricles. At the atrium myocardium consists of two layers: superficial (total for both atrial), and deep (separate). In the surface layer, muscle beams are located transversely, in a deep layer - longitudinally.

Miocardian ventricles consists of three different layers: external, medium and internal. In the outer layer, muscle bundles are cosos, starting from fibrous rings, continue down to the top of the heart, where the heart curls form. The inner layer of myocardium consists of longitudinally arranged muscle beams. Due to this layer, puzzle muscles and trabecules are formed. The outer and inner layers are common to both ventricles. The middle layer is formed by circular muscle beams, separate for each ventricle.

Epicard is built according to the type of serous shells and consists of a thin plate of the connective tissue coated with mesothelium. Epicard covers the heart, the initial departments of the upward part of the aorta and the pulmonary trunk, the final departments of hollow and pulmonary veins.

Structure of the wall of the heart

The wall of the heart includes three shells: inner - endocardium, middle - myocardium and outdoor - epicard.

Structure of the wall of the heart

Endocard, Endocardium, relatively thin sheath, lins the chambers of the heart from the inside. In the composition of the endocardium distinguish: endothelium, subendothelial layer, muscular-elastic and external connective ones. Endothelium is represented by only one layer of flat cells. The endocardia without a sharp boundary goes to large awarded vessels. Folding valves and flaps of semi-lunk valves are an endocarda duplication.

Myocardia, Myocardium, the most significant shell in thickness and the most important function. Myocardium is a different structure consisting of transverse muscle tissue, loose and fibrous connective tissue, atypical cardiomyocytes, vessels and nerve elements. The combination of reduced muscle cells is a heart muscle. The heart muscle has a special structure, occupying an intermediate position between the transverse and smooth muscles. The fibers of the heart muscle are capable of rapid contractions, interconnected by jumpers, as a result of which a wide-pushed network is formed, referred to as synzyt. Muscular fibers are almost deprived of the shell, their kernels are in the middle. Reducing the muscles of the heart is performed automatically. Musculatory atrial and ventricles anatomically separately. They are connected only to the system of conductive fibers. Atrial myocardium has two layers: superficial, whose fibers are going cross, covering both atrium, and deep separate for each atrium. The latter consists of vertical beams starting from fibrous rings in the field of preservative holes and from circular beams located in the mouths of hollow and pulmonary veins.

The myocardium of the ventricles is much more difficult than myocardium atrium. There are three layers: outer (superficial), medium and internal (deep). Punches of the surface layer, common to both ventricles, start from fibrous rings, go to the top to the top of the heart. Here they are wrapped back, go deep into the depth, forming the heart curl in this place, Vortex Cordis. Not interrupting, they go into an internal (deep) layer of myocardium. This layer has a longitudinal direction, forms fleshy trabecules and nobble muscles.

Between surface and deep layers lies the average - circular layer. It is separate for each of the ventricles, and is better developed on the left. Its beams are also starting from fibrous rings and go almost horizontally. Between all muscle layers there are numerous binding fibers.

In the wall of the heart, in addition to muscle fibers, there are connecting formations - this is its own "soft skeleton" of the heart. It performs the role of supporting structures from which muscle fibers begin and the valves are fixed. The soft skeleton of the heart includes four fibrous rings, nnuli fibrosi, two fibrous triangles, Trigonum Fibrosum, and a webbed part of the interventricular partition, Pars Membranacea Septum Interventriculare.

Motor miocardial fabric

Fibrous rings, Annlus Fibrosus Dexter Et Sinister, surround the right and left atrial stomach holes. Make up a support for a three-risk and two-sided valves. The projection of these rings on the surface of the heart corresponds to the corrosion. Similar fibrous rings are located in the circumference of the mouth of the aorta and the pulmonary trunk.

The right fibrous triangle is more left. It occupies a central position and actually connects the right and left fibrous rings and the connecting rings of the aorta. On the bottom, the right fibrous triangle is connected to a webbed part of the interventricular partition. The left fibrous triangle is significantly less, it connects to Anulus Fibrosus Sinister.

The base of the ventricles, the atrium is removed. Mitral valve left below

Atypical cells of the conductive system, forming and conductive pulses, provide automatism of reducing typical cardiomyocytes. They constitute a conductive heart system.

Thus, in the composition of the muscular shell of the heart, three functionally interconnected devices can be distinguished:

1) contractual, presented by typical cardiomyocytes;

2) reference formed by connective tissue structures around the natural holes and penetrating myocardium and epicard;

3) conductive, consisting of atypical cardiomyocytes - cells of the conductive system.

Epicard, Epicardium, covers the heart outside; Under it are their own heart vessels and fatty fiber. It is a serous shell and consists of a thin plate of connective tissue coated with mesothelium. Epicard is also called the visceral plate of serous pericardia, Lamina Visceralis Pericardii Serosi.

Structure of the walls of the heart

In the heart of the heart, 3 layers are isolated: the thin inner layer is an endocardium, a thick muscular layer - myocardium and a thin outer layer - an epicardium, which is a visceral leaflet of the serous heart-shell - pericardium (near-smooth bag).

Endocard (Endocardium) lins the cavity of the heart from the inside, repeating its complex relief, and covers the puffy muscles with their tendon chords. Atrial and ventricular valves, aortic valve and a pulve of the pulmonary trunk, as well as the flaps of the lower hollow vein and the corinese sinus are formed by endocarda duplicates, inside of which connective tissue fibers are located.

An endocardium is formed by one layer of flat polygonal endotheliocytes located on a fine basal membrane. In the cytoplasm of endothelocytes a large number of micropinocytous bubbles. Endotheliocytes are connected to each other with intercellular contacts, including nexus. On the border with myocardium there is a thin layer of loose fibrous connective tissue. The average layer of the wall of the heart - myocardium (myocardium) is formed by a heart cross-striped muscle tissue and consists of hearty myocytes (cardiomyocytes). Cardiomyocytes are interconnected by a large number of jumpers (inserted discs), with the help of which they are associated with muscle complexes that form a narrow-scale network. This muscular network provides a complete rhythmic reduction in atrial and ventricles. Myocardine thickness is the smallest at the atria, and the greatest - at the left ventricle.

Myocardium atserval Separated by fibrous rings from the myocardium of ventricles. The synchronization of myocardial cuts provides a conductive heart system, one for atria and ventricles. At the atrium myocardium consists of two layers: superficial, common to both atrium, and deep, separate for each of them. In the surface layer, muscle beams are located transversely, in a deep layer - longitudinally. Circular muscle bundles loop-like covers the mouths of the veins, flowing into the atrium, like compressors. Longly lying muscular bundles originate from fibrous rings and in the form of vertical seasus, they are filled into the cavities of the atria's ears and form comb muscles.

Myocardian Zholdokkov It consists of three different muscle layers: external (superficial), medium and internal (deep). The outer layer is represented by space-oriented muscle beams, which, starting from fibrous rings, continue down to the top of the heart, where the heart curls form (Vortex Cordis). Then they pass into the internal (deep) layer of myocardium, the beams of which are located longitudinally. Due to this layer, puzzle muscles and fleshy trabecules are formed. The outer and inner layers of myocardium are common to both ventricles. Located between them the middle layer formed by circular (circular) muscle beams, separate for each ventricle. The interventricular partition is formed in a greater part (its muscular part) myocardium and its endocardium covering it. The basis of the upper portion of this partition (its webbed part) is a plate of fibrous tissue.

The outer sheath of the heart is epicardium (Epicardium), adjacent to myocardium outside, is a visceral dial leaflet. Epicard was built by the type of serous shells and consists of a thin plate of the connective tissue coated with mesothelium. Epicard covers the heart, the initial departments of the upward part of the aorta and the pulmonary trunk, the final departments of hollow and pulmonary veins. According to these vessels, epicardes goes into a parietal plate of serous pericardia.

Medical Expert Editor

Portnov Alexey Alexandrovich

Education: Kiev National Medical University. A.A. Bogomolets, specialty - "Therapeutic business"

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Structure of the wall of the heart.

The steppe of the heart consists of three layers: external - epicardine, medium-myocardium and internal - endocardium. Outer sheath of the heart. Epicard, Epicardium, is a smooth, thin and transparent shell. It is a visceral plate, Lamina Visceralis, Pericarda, Pericardium. The connective tissue of the epicardium in different parts of the heart, especially in the furrows and in the top of the top, includes fatty tissue. With the help of connective tissue, Epicard faded with myocardium most tight in places of the smallest cluster or lack of adipose tissue (see "Pericard").

Muscular heart sheath, or myocardium. Middle, muscular, shell heart, myocardium, or heart muscle, is a powerful and large part of the heart wall thickness. The greatest thickness of myocardium reaches in the region of the left ventricle (11-14 mm), twice the thickness of the wall of the right ventricle (4-6 mm). In the walls of the atrium myocardia is significantly less developed and the thickness of it here is only 2 - 3 mm.

Between the muscular layer of atria and the muscular layer of ventricles, there is a dense fibrous fabric, at the expense of which fibrous rings, right and left, Anuli Fibrosi, Dexter Et Sinister are formed. Co. The sides of the outer surface of the heart their location corresponds to the Crown Barrout.

The right fibrous ring, Anulus Fibrosus Dexter, which surrounds the right atrocaded-ventricular hole, has the form of oval. The left fibrous ring, Anulus Fibrosus Sinister surrounds the left at the vestricular hole on the right, on the left and behind and in the form of a horseshoe.

With their front areas, the left fibrous ring is attached to the root of the aorta, forming around the rear of its periphery triangular connective tissue plates - the right and left fibrous triangles, Trigonum Fibrosum Dextrum et TIGOPIT FIBROSUM SINISTRUM.

The right and left fibrous rings are interconnected into a common plate, which is completely, with the exception of a small area, isolating the muss of the atriality from the muscles of the ventricles. In the middle of the connecting ring of the fibrous plate, there is a hole through which the musculatory of the atria is connected to the muscles of the ventricles by means of a preservative beam.

In the circumference of the holes of the aorta and the pulmonary trunk are also interconnected fibrous rings; The aortal ring is connected to the fibrous rings of atrial and ventricular holes.

Muscle sheath atrial. In the walls of the atria distinguish two muscle layers: superficial and deep.

The surface layer is common to both atrium and is muscle beams that are mainly in the transverse direction. They are more pronounced on the front surface of the atria, forming a relatively wide muscular layer in the form of a horizontally located interrupted beam, moving to the inner surface of both ears.

On the rear surface of the atria, muscle bundles of the surface layer are in part in the rear partitions. On the rear surface of the heart, between the bunches of the surface layer of the muscles, there is an epicardine-covered recess, limited by the mouth of the lower vein hollow, the projection of the interprisened partition and the mouth of the venous sine. At the site, the atrial stems are included in the atria partition, which innervate the atrial septum and ventricular partition, is an atrial stomach bundle.

The deep layer of muscles of the right and left atriality is not common to both atrium. It distinguishes circular and vertical muscle bundles.

Circular muscle bundles in large numbers lie in the right atrium. They are located mainly around the holes of the hollow veins, turning onto their walls, around the coronary sinus of the heart, at the mouth of the right ears and the edge of the oval pits: in the left atrium they lie mainly around the holes of the four pulmonary veins and at the beginning of the left ear.

Vertical muscular bundles are perpendicular to the fibrous rings of atrial and ventricular holes, attaching to them with their ends. A part of the vertical muscle beams is included in the thickness of the beds of the atrial and ventricular valves.

Great muscles, mm. Pectinati. Also formed by the deep layer beams. They are most developed on the inner surface of the ending the wall of the cavity of the right atrium, as well as the right and left ears; In the left atrium, they are less pronounced. In the intervals between the comb's muscles, the wall of the atria and the ears are especially thinned.

On the inner surface of both ears there are short and thin beams, so-called fleshy trabecules, TRABECULAE CARNEAE. Crossing in different directions, they form a very subtle loop-shaped network.

Muscular sheath of ventricles. In the muscular shell (myocardium) there are three muscular layers: outdoor, medium and deep. Outdoor and deep layers, moving from one ventricle to another, are common in both ventricles; The average, although connected with two other layers, surrounds each ventricle separately.

The outer, relatively thin layer consists of oblique, part of the rounded, part of the bleached beams. The beams of the outer layer begin at the base of the heart from the fibrous rings of both ventricles and partly from the roots of the pulmonary trunk and aorta. On the chest-rib (front) surface of the heart, the outer beams go to the right left, and on the diaphragmal (bottom) - from left to right. At the top of the left ventricle, those and other beams of the outer layer form the so-called heart curl, Vortex Cordis, and penetrate into the depth of the walls of the heart, turning into a deep muscular layer.

The deep layer consists of beams rising from the top of the heart to its base. They have a cylindrical, and part of the bunches oval shape, are repeatedly split and again connected, forming different loops. The shorter of these beams do not reach the base of the heart, directly from one heart of the heart to the other in the form of fleshy trabeculs are directed. Only the interventricular partition immediately under the arterial holes are devoid of these crossbars.

A number of such short but more powerful muscle beams associated partly and with an average, and with an outer layer, acts into the cavity of the ventricles freely, forming various magnitude of cone-shaped puffy muscles.

Peduced muscles with tendon chords hold the valve sash when they slam the blood current, heading from abbreviated ventricles (with systole) in relaxed atrial (with diastole). When encouraging obstacles from the valves, blood is not asked not to the atrium, but in the holes of the aorta and the pulmonary trunk, the semi-lone flaps of which are pressed the blood current to the walls of these vessels and thereby leave the clearance of the vessels open.

Located between outer and deep muscle layers, the average layer forms a number of well-pronounced circular beams in the walls of each ventricle. The average layer is more developed in the left ventricle, therefore the walls of the left ventricle are much thicker than the walls of the right. Punches of the middle muscular layer of right ventricle are flattened and have almost transverse and somewhat obliquely from the heart base to the top direction.

The interventricular partition, septum interventriculare, is formed by all three muscular layers of both ventricles, but more muscle layers of the left ventricle. The thickness of the partition reaches 10-11 mm, slightly yielding the thickness of the left ventricular wall. The interventricular partition is convex towards the cavity of the right ventricle and for 4/5 represents a well-developed muscular layer. This significantly most of the interventricular partition is called the muscular part, Pars Muscularis.

The top (1/5) part of the interventricular partition is a webbed part, Pars Membranacea. The scene of the right atrial and ventricular valve is attached to the connecting part.

Structure of the walls of the heart

The walls of the heart consist of 3 shells: internal - endocardium, medium - myocardium and outer - epicardium, which is a visceral leaflet of pericardium, Pericardium.

The thickness of the heart walls is mainly formed by the middle shell, myocardium, myocardium, consisting of heart-worked muscular tissue. Outdoor shell,

epicardium represents serous cover. Inner shell, endocard, endocardium, lins the cavity of the heart.

Miocard, myocardium, or muscular heart fabric, although it has transverse aperture, but differs from skeletal muscles in that it consists not of individual multi-core

fibers, and represents a network of single-core cells - cardiomyocytes. In the muscles of the heart distinguish two departments: muscle layers atrium and muscle layers

ventricles. Fibers of those and others start from two fibrous rings - Anuli Fibrosi, of which one surrounds Ostium Atrioventriculare Dextrum, Other - Ostium Atrioventriculare

sinistrum. Since the fibers of one department, as a rule, do not go into the fibers of the other, the result is the possibility of reducing the atrium separately from the ventricles.

In the atria distinguishes the surface and deep muscle layers: the surface consists of circular or transversely arranged fibers, deep - from longitudinal,

which by their ends begin with fibrous rings and loopped at the atrium. Around the circumference of large venous trunks flowing into the atrium

circular fibers covering them, as if sphincters. The fibers of the surface layer cover both atrium, deeply belongs to each atrium.

The muscles of the ventricles is even more difficult. It can distinguish three layers: a thin surface layer is composed of longitudinal fibers that begin with the right

the fibrous ring and goes aside, turning onto the left ventricle; At the top of the heart, they form curl, Vortex Cordis, bending here loop-like in depth and

by consting the inner longitudinal layer, the fibers of which are attached to the fibrous rings with its top ends. The fibers of the middle layer located between

longitudinal outer and inner, go more or less circularly, and, unlike the surface layer, do not go from one ventricle to another, and are

independent for each ventricle. An important role in the rhythmic work of the heart and the coordination of the muscles of individual heart chambers is played by the so-called

conductive heart system. Although the muscles of the atria is separated from the muscles of the ventricles with fibrous rings, but there is a connection between them through

conductive system, which is complex neuromuscular education. Muscular fibers included in its composition (conductive fibers) have a special structure: their

cells are poor in myofibrils and rich in sarcoplasma, so lighter. They are sometimes visible to the naked eye in the form of light painted threads and represent less

the differentiated part of the initial syncytia, although the magnitude exceeds the usual muscle fibers of the heart. The conductive system distinguishes nodes and beams.

1. The sine-atrial node, Nodus Sinuatralis, is located in the walls of the right atrium, corresponding to the Sinus Venosus cold-blooded (in Sulcus Terminalis,

between the upper hollow vein and right ear). It is associated with the midstrial muscles and matters to their rhythmic reduction.

2. Atrial-ventricular node, Nodus Atrioventricularis, located in the wall of the right pride, near the cuspis septalis of the three-rolled valve. Fibers node,

importance directly associated with muscles, continue to the partition between the ventricles in the form of an atrial stomach beam, Fasciculus Atrioventricularis

(Bunch of Gis). In the ventricular partition, the bundle is divided into two legs - Crus Dextrum ET SINISTRUM, which go to the walls of co-vertices and branch under the endocardium in their

musculature. The atrief ventricular beam is very important for the work of the heart, since the wave of reduction with atria on the ventricles is passed on it.

thereby establishing the regulation of the rhythm of systole - atrial and ventricles.

Consequently, the atrium is interconnected by a sinus-atrial node, and atrium and ventricles are an atrief-ventricular beam. Usually irritation is

the right atrium is transferred from the sinus-atrial node to the atrocadic and ventricular, and from it according to the atrocarditricular beam on both stomach.

Epicard, Epicardium, covers the outside of myocardium and is a conventional serous shell, lined on the free surface of the mesothelium.

Endochd, Endocardium, lins the inner surface of the heart cavities. It in turn consists of a layer of connective tissue with a large number of elastic

fibers and smooth muscle cells, from the exterior of another layer of connective tissue with an admixture of elastic fibers and from the internal endothelial

the layer than endocardia differs from epicarda. Endocardia according to its origin corresponds to the vascular wall, and the listed layers of it is 3 vessel shells. All cordial

valves represent the folds (duplication) endocardium.

The described features of the structure of the heart determine the features of its vessels that form a separate circle of blood circulation - the heart (third round).

Artery hearts - aa. Coronariae Dextra Et Sinistra, Crown Arteries, Right and Left, start from Bulbus Aortae below the upper edges of the semi-lunged valves. Therefore, V.

systole time The entrance to the coronary artery is covered with valves, and the arteries themselves are compressed by the abbreviated heart muscle. As a result, during systole blood supply

hearts decreases: blood in the coronary artery arrives during the diastole, when the inlet holes of these arteries located in the mouth of the aorta are not closed by half

Right Crown Artery, a. Coronaria Dextra, comes out of the aorta, respectively, the right semi-lunar damper and falls between the aorta and the Easter of the right atrium, the duck

from which she envelopes the right edge of the heart along the Crown Borozde and moves to his back surface. Here it continues to the interventricular branch, R. interventricularular

posterior. The latter descends over the rear interventricular furrow to the top of the heart, where he anastomoses with the branch of the left cornoe artery.

The branches of the right corn-free artery vascuarize: the right atrium, part of the front wall and the entire back wall of the right ventricle, a small area of \u200b\u200bthe rear wall

left ventricle, interpresenting partition, rear third of the interventricular partition, puffy muscles of the right ventricle and the rear puffy muscle of the left

Left Viennese Artery, A.Coronaria Sinistra, coming out of the aorta at the left half-lift damper, also falls into the Kornevnaya groove Kepened from the left atrium. Between

light barrel and left ear it gives two branches: a thinner front, interventricular, Ramus Interventricularis Anterior, and a larger left, envelope, Ramus

The first is descended by the front interventricular furrow to the top of the heart, where it anastomoses with the branch of the right corner artery. The second, continuing the main

the trunk of the left cornese artery, envelopes on the Crown Barrouts the heart on the left side and also connects to the right corveric artery. As a result, across the corner

an arterial ring is formed, located in a horizontal plane, from which perpendicularly departs branches to the heart. Ring is functional

device for collateral heart circulation of the heart. The branches of the left cornese artery vascuate the left atrium, the entire front wall and most of the rear

the walls of the left ventricle, part of the front wall of the right ventricle, the front 2/3 of the interventricular partition and the front puzzle muscle of the left ventricle.

There are various vapints of the development of corn-free arteries, as a result of which there are different ratios of blood supply pools. From this point of view distinguish

three forms of blood supply to the heart: uniform with the same development of both coronary arteries, left-hand and legal.

In addition to the coronary arteries, the "additional" arteries from the bronchial arteries are suitable, from the lower surface of the aorta arc near the arterial ligament, which is important

to take into account not to damage them during operations on the lungs and the esophagus and this does not worsen the blood supply to the heart.

The intraongal artery of the heart: from the trunks of the coronary arteries and their large branches, respectively, 4 chambers of the heart are departed by the branches of the atrium (RR. Atriales) and their ears (RR.

auriculares), ventricular branches (RR. VENTRICULARES), partition branches (RR. Septales Anteriores et Posteriores). Penetrating myocardial in the thickness, they branched out respectively

the number, location and device of the layers of it: first in the outer layer, then on average (in the ventricles) and, finally, in the internal, after which they penetrate into the nobble muscles (AA.

papillares) and even in the preservative valves. Intramuscular artery in each layer follow the course of muscle beams and anastomed in all layers and departments

Some of these arteries have a strongly developed layer of involuntary muscles in their wall, with a reduction in which a complete closure of the vessel lumen occurs,

why these artery call "closing". The temporary spasm of the "closing" arteries can entail the cessation of blood current to this section of the heart muscle and

call myocardial infarction.

Heart veins are open not in the hollow veins, but directly into the cavity of the heart.

Intramuscular veins are located in all layers of myocardium and, accompanying the artery, correspond to the movement of muscle beams. Small arteries (up to 3rd order) are accompanied by

double veins, large - single. The venous outflow is in three ways: 1) in the belling sine, 2) in the front veins of the heart and 3) in the smallest veins flowing

directly into the right heart department. In the right half of the heart of these veins, more than in the left, in connection with which the corpling veins are more developed on the left.

The predominance of the smallest veins in the walls of the right ventricle with a small outflow of the vein system of the Vernoe sinus indicates that they play an important role in

redistribution of venous blood in the heart area.

1. Vienna Sinus Sine, Sinus Coronarius Cordis. It is the residue of the left overall cardinal vein and lies in the backyard of the angry groove of the heart,

between the left atrial and left ventricle. With his right, thicker end, he flows into the right atrium near the partition between the ventricles, between the damper

bottom hollow vein and atrium partition. The following veins fall into Sinus Coronarius:

a) v. Cordis Magna, starting at the top of the heart, raises her along the front interventricular headorrod of the heart, turns to the left and, rebuilding left

hearts continues in Sinus Coronarius;

b) v. Posterior Ventriculi Sinistri is one or more venous trunks on the back surface of the left ventricle, which flows into the Sinus Coronarius or v. CORDIS MAGNA;

c) v. Obliqua Atrii Sinistri is a small branch located on the back surface of the left atrium (the residue of the germinal v. Cava Superior Sinistra); It begins in

the fold of the pericardia, which concludes the connecting tapery, PLICA VENAE CAVAE SINISTRAE, also representing the remainder of the left half of the vein;

d) v. Cordis Media lies in the rear interventricular furrow and, reaching the transverse groove, flows into Sinus Coronarius;

e) V.CORDIS PARVA - a thin branch located in the right half of the transverse head of the heart and flowing usually in v. Cordis Media in the place where this vein reaches

2. Front Vienna Hearts, VV. Cordis Anteriores, - small veins are located on the front surface of the right ventricle and fall directly into the right cavity

3. The smallest veins of the heart, VV. Cordis Minimae, - very small venous trunks, do not appear on the surface of the heart, and, having gathered from the capillaries, fall right in

atrial cavities and to a lesser degree of ventricles.

In the heart there are 3 lymphatic capillaries: under the endocardium, inside myocardium and under the epicardium. Among the discharge vessels are formed two main

lymphatic heart collector. The right collector arises from the beginning of the rear interventricular furrow; he takes lymph from right ventricle and atrium and reaches

the left upper front nodes of the mediastone lying on the aortic arc near the beginning of the left total carotid artery.

The left collector is formed in the Vernoy Barrout at the left edge of the pulmonary trunk, where the vessels carrying lymph from the left atrium, left ventricle and

partly from the front surface of the right ventricle; Further, it is sent to the tracheobrichial or tracheal nodes either to the nodes of the root of the left lung.

The nerves that ensure the innervation of cardiac muscles, which has a special structure and function, differ in complexity and form numerous plexuses.

The entire nervous system is composed of: 1) suitable trunks, 2) extracardial plexus, 3) plexuses in the heart and 4) with the plexus of nodal fields.

Functionally the nerves of the heart are divided into 4 species (I.P. Pavlov): slowing and accelerating, weakening and reinforcing. Morphologically, these nerves go in N.

vagus and the branches of Truncus Sympathicus. Sympathetic nerves (mainly postgangle fibers) depart from TPEX upper cervical and five top chest sympathetic

nodes: n. Cardiacus Cervicalis Superior - from Ganglion Cervicale Superius, N. Cardiacus Cervicalis Medius, from Ganglion Cervicale Medium, N.Cardiacus Cervicalis Inferior - from Ganglion

cervicale Inferius or Ganglion Cervicothoracicum and NN.Cardiaci Thoracici from the chest nodes of the sympathetic barrel.

Cardic branches of a wandering nerve begins from his cervical department (Rami Cardiaci Cervicalis Superiores), Breast (Rami Cardiaci Thoracici) and from N. Laryngeus Recurrens.

vagi (Rami Cardiaci Cervicales Inferiores). Suitable to the heart of the nerves are composed into two groups - surface and deep. The surface group arrives in the upper department to

sleepy and plug-in arteries, in the lower - to the aorta and the pulmonary barrel. The deep group, compiled mainly by the branches of the wandering nerve, falls on the front

the surface of the lower third of the trachea. These branches come into contact with lymphatic nodes located in the field of trachea, and with an increase in nodes, for example, with tuberculosis

lungs may be squeezed by them, which leads to a change in the rhythm of the heart. Two nervous plexuses are formed from listed sources:

1) superficial, Plexus Cardiacus superficialis, between the arc of the aorta (under it) and the bifurcation of the pulmonary trunk;

2) Deep, Plexus Cardiacus Profundus, between Arc Aorta (behind it)

and trachea bifurcation.

These plexuses continue at the Plexus Coronarius Dexter Et Sinister surrounding the co-vessels, a taper in the plexus located between the epicardium and myocardium. From

the last plexus departs intraganic branching nerves. The plexus contains numerous groups of ganglion cells, nerve nodes.

The afferent fibers begin with receptors and go along with the efferent in the composition of the wandering and sympathetic nerves.

133. Heart wall layers, their functions.

Heart, Cor (Greek Cardia), is a hollow organ, the walls of which consist of three layers - internal, medium, outdoor.

Inner shell, endockard, Endocardium is represented by a layer of endotheliocytes. The endocardium is covered with all the structures inside the heart chambers. Its derivatives are all valves and dampers in the heart. This shell provides a laminar blood flow.

Medium shell, Myocardium, Myocardium is formed by the worn muscle cells (cardiomyocytes). Provides a reduction in atria and ventricles.

Outer shell, Epicard, Epicardium is represented by a serous shell, which is a visceral leaflet of pericardia. The shell provides a free shift of the heart when it is reduced.

134. The degree of severity of the muscular layer in the heart chambers.

The muscular layer has a different thickness in the heart chambers, which depends on the work performed by them. The greatest thickness of this layer - in the left ventricle, because It provides blood flow by big circle blood circulation, overcoming huge friction forces. In second place is the thickness of the myocardium in the wall of the right ventricle, providing blood flow through a small circulation of blood circulation. And finally, this layer is least expressed in the walls of the atria, ensuring the movement of blood from them in the ventricles.

135. Features of the structure of the myocardium of ventricles and atrium.

The atrium myocardium consists of two layers: surface - Total for both ventricles and deep - Separate for each of them.

In the ventricles myocardium consists of three layers: outdoor (superficial), medium and internal (deep).

The outer and internal layers are common to both ventricles, and the middle layer is separate for each ventricle. Muscle fibers atrial and ventricles are isolated from each other.

Derivatives of the deep layer of the myocardial of ventricles They are puffy muscles and fleshy trabecules.

Derivatives of the outer layer of the myocardial atrial Great muscles are.

136. Big and small circles circulation, their functions.

Big circle circulation Provides blood flow in the following direction: from left ventricle → in aorta → to organ artery → in ICR organs → to organ veins → in hollow veins → to the right atrium.

Small circle circulation Provides blood flow in a different direction: from the right ventricle → to the pulmonary barrel → to pulmonary arteries → in the ICR of the oscincions of the lung → into pulmonary veins → in the left atrium.

Both circulation of blood circulation are integrated parts of a single circle of blood circulation and perform two functions - transport and exchange. In a small circle, the exchange function is mainly associated with oxygen gas exchange and carbon dioxide.

137. Heart valves, their functions.

There are four valves in the heart: two folded and two semi-short.

Right atrial and ventricular (three-rolled) valve Located between the right atrium and the ventricle.

Left atrial and ventricular (mitral) valve Located between the left atrium and the ventricle.

Valve of the pulmonary trunkValva Trunci Pulmonalis is located within the base of the pulmonary trunk.

Aorti valveValva Aortae is located within the base of the aorta.

In practice, the process of heat transfer through a flat wall consisting of several layers of material with different thermal conductivity is of great importance. For example, the metal wall of the steam boiler, covered with the outer side by slags, and with the inner scale, is a three-layer wall.

Consider the process of transferring heat thermal conductivity through a flat-three-layer wall (Fig. 7). All layers of such a wall are tightly adjacent to each other. The thicknesses of the layers are indicated δ 1, δ 2 and δ 3, and the thermal conductivity coefficients of each material λ 1, λ 2 and λ 3, respectively. The temperatures of the outer surfaces T l and T 4 are also known. Temperatures T 2 and T 3 are unknown.

The process of transmitting heat thermal conductivity through a multilayer wall is considered in stationary mode, therefore the specific heat flux q passing through each layer of the wall is constant in magnitude and for all layers of the same, but in its path it overcomes the local thermal resistance of the Δ / λ of each wall layer. Therefore, on the basis of formula (54), you can write for each layer:

Folding the left and right parts of equalities (58), we obtain a complete temperature pressure consisting of the amount of temperature changes in each layer:

It follows from equation (59) that the total thermal resistance of the multilayer wall is equal to the sum of the thermal resistances of each layer:

According to formulas (58) and (59), you can get the values \u200b\u200bof unknown temperatures t 2. and T 3:

The temperature distribution in each layer of the wall at λ-const is subject to the linear law, which is seen from the equality (58). For a multilayer wall as a whole, the temperature curve is a broken line (Fig. 7).

Formulas obtained for a multilayer wall can be used under the condition of good thermal contact between the layers. If at least a small air gap appears between the layers, then thermal resistance will increase significantly, since the thermal conductivity of the air is very small:

[λ B03D \u003d 0.023 W / (m hail)].

If the presence of such a layer is inevitable, then it is considered at the calculations as one of the layers of a multilayer wall.

Convective heat exchange. Convective heat exchange is a heat exchange between solid and liquid (or gas), accompanied by thermal conductivity and convection at the same time.

The phenomenon of thermal conductivity in the liquid, as in the solid body, is fully determined by the properties of the fluid itself, in particular the coefficient of thermal conductivity and the temperature gradient.

When convection, the warmth transfer is inextricably linked to the transfer of the fluid. This complicates the process, since the transfer of the fluid depends on the nature and nature of the occurrence of its movement, the physical properties of the fluid, the shape and size of the surfaces of the solid body, etc.

Consider the case of flowing near the solid wall of the fluid, the temperature of which is lower than (or above) the temperature of the wall. The heat exchange occurs between the liquid and wall. The transition of heat from the wall to the liquid (or back) is called heat transfer. Newton showed that the amount of heat q, which exchange the temperature of T, and the fluid having the temperature t f, directly proportional to the temperature difference T st - t and the surface area of \u200b\u200bthe contact S:

Q \u003d αS (T ST - T G) (60)

where α is the heat transfer coefficient, which shows the amount of heat for one second, the fluid and wall are exchanged for one second, if the temperature difference between them is 1 K, and the surface area is washed with liquid is 1 m 2. In the coefficient of the heat transfer coefficient is W / (M 2 K). The heat transfer coefficient α depends on many factors, and first of all on the nature of the fluid movement.

Turbulent and laminar movement of fluid corresponds different nature Transmission of heat. When laminar movement, the heat is propagated in the direction perpendicular to the movement of the particles of the liquid, as well as in the solid body, i.e. thermal conductivity. Since the thermal conductivity coefficient is small, the heat is spread when laminar flow in the direction perpendicular to the flow, very weakly. With turbulent movement, the layers of liquid (more and less heated) are mixed, and the heat exchange between the liquid and the wall in these conditions is more intense than when laminar flow. In the border layer of fluid (at the pipe walls), heat is transmitted only with thermal conductivity. Therefore, the border layer is a large resistance to the flow of heat, and it takes the greatest loss of temperature pressure.

In addition to the nature of the movement, the heat transfer coefficient depends on the properties of the liquid and solid body, the fluid temperature, etc. Thus, the theoretically determine the heat transfer coefficient is quite difficult. Based on a large experimental material, the following values \u200b\u200bof heat transfer coefficients were found [in W / (m 2 K)], for various cases of convective heat exchange:

Basically, the convective heat exchange occurs with the longitudinal forced flow of the fluid, for example, heat exchange between the pipe walls and the fluid flowing through it; transverse forced streaming, such as heat exchange when washing the pipe beam liquid; free movement, such as heat exchange between the liquid and the vertical surface, which it is washes; Changes in an aggregate state, for example, heat exchange between the surface and liquid, as a result of which the liquid boils or the condensation of its vapors occurs.

Rady heat exchange. The radiant heat exchange is called the process of heat transfer from one body to another in the form of radiant energy. In heat engineering under high temperatures, heat transfer is of paramount importance. Therefore, modern heat engineering aggregates designed for high temperatures use this type of heat exchange as possible.

Any body whose temperature is excellent from the absolute zero, emits electromagnetic waves. Their energy is able to absorb, reflect, and also to miss any other body through itself. In turn, this body also emits energy, which, together with the reflected and missed energy, falls on the surrounding bodies (including the first body) and again absorbed, is reflected by them, etc. Of all electromagnetic rays, infrared has the greatest thermal effect and visible rays with a wavelength of 0.4-40 μm. These rays are called thermal.

As a result of the absorption and radiation of the bodies of radiant energy, heat exchange occurs between them.

The amount of heat absorbed by the body as a result of a radiant heat exchange is equal to the difference between the energy falling on it, and the emitted it. This difference is different from zero if the temperature of the bodies participating in the mutual exchange of radiant energy is different. If the temperature of the body is the same, then the entire system is in movable thermal equilibrium. But in this case, the bodies are still emitted and absorbed radiant energy.

The energy emitted by the unit of the body surface per unit of time is called its radiative ability. Unit of radiative ability W / M A.

If Q 0 of energy falls on the body per unit of time (Fig. 8), Q R is reflected, Q d passes through it, Q A is absorbed by them,

(61)

where Q A / Q 0 \u003d A is the absorption capacity of the body; Q r / q O \u003d R is the reflectivity of the body; Q D / Q 0 \u003d D - transmitting body ability.

If a \u003d 1, then r \u003d d \u003d 0, i.e. all the incident energy is completely absorbed. In this case, it is said that the body is absolutely black. If R \u003d 1, Ta \u003d D \u003d 0 and the incidence of rays is equal to the reflection angle. In this case, the body is absolutely mirror, and if the reflection diffuse (uniform in all directions) is absolutely white. If d \u003d 1, to a \u003d r \u003d 0 and the body is absolutely transparent. In nature, there is neither absolutely black, nor absolutely white, nor absolutely transparent bodies. Real bodies can only approach one such species of bodies.

The absorption capacity of various bodies is different; Moreover, the same body absorbs the energy of various wavelengths. However, there are bodies for which at a certain interval of wavelengths, the absorption capacity is little dependent on the wavelength. Such bodies are customized with gray wavelengths for this interval. Practice shows that in relation to the wavelength intervals used in heat engineering, very many bodies can be considered gray.

The energy emitted by the unit of the surface of the absolutely black body per unit of time is proportional to the fourth degree of absolute temperature (the law of Stephen-Boltzmann):

E 0 \u003d Σ "0 ton, where σ" 0 is an absolutely black body radiation constant:

σ "0 \u003d 5.67-10-8 W / (m 2 - to 4).

Often this law is written in the form of

where - the radiation coefficient of absolutely black bodies; \u003d 5.67 W / (m 2 to 4).

Many emission laws installed for absolutely black bodies are of great importance for heat engineering. Thus, the cavity of the windbox of the boiler installation can be viewed as a model of absolutely black body (Fig. 9). In relation to such a model, the laws of radiation of absolutely black bodies are performed with great accuracy. However, using these laws in relation to thermal installations should be carefully. For example, for the gray body, the Stefan-Boltzmann law is similar to formula (62):

(63)

where the ratio / is called the degree of black ε (ε, the greater, the greater the body under consideration differs from the absolute black, Table 4).

Formula (63) is used to determine the emissivity of the furnace, the surface of the burning fuel layer, etc. The same formula is used when taking into account heat transmitted by radiation in the heat chamber, as well as elements of the boiler.

The bodies fill in the inner space of the furnace are continuously emitted and absorbed energy. However, the system of these bodies is not in a state of thermal equilibrium, since their temperature is different: in modern boilers, the temperature of the pipes on which water and steam are undergoing, significantly lower the temperature of the flue space and the inner surface of the furnace. Under these conditions, the emissivity of pipes is significantly less

Table 4.

emitting the ability of the furnace and its walls. Therefore, heat transfer by radiation passing between them is mainly carried out in the direction of transmission of energy from the furnace to the surface of the pipes.

In the radiant heat exchange between two parallel surfaces with the degrees of black ε 3 and ε 2, having the temperature T 1 and T 2, respectively, the amount of energy they exchange are determined by the formula

If the bodies between which the radiant heat exchange is limited to the surfaces and S 1 and S 2, located inside each other, then the reduced radiation coefficient is determined by the formula

(66)

Heat transfer

The heat exchange between the hot and cold medium through the separation solid wall is one of the most important and frequently used processes. For example, the preparation of a pair of specified parameters in the boilers is based on the process of heat transfer from one coolant to another. In numerous heat exchange devices used in any field of industry, the main workflow is the heat exchange process between coolants. Such heat exchange is called heat transfer.

For example, consider one-layer (Fig. 10) the wall whose thickness is equal to Δ. The thermal conductivity coefficient of the wall material is λ. The temperatures of mediums that wash the wall on the left and right are known and are equal to T 1 and T 2. We assume that T 1\u003e T 2. Then the temperature of the wall surfaces will be, respectively, T St1\u003e / T St2. It is required to determine the thermal flow q passing through the wall from the heating medium to the heated.

Since the heat transfer process under consideration proceeds under inpatient mode, the heat, given by the wall by the first coolant (hot), is transmitted through it the second coolant (cold). Using the formula (54), you can write:

Folding these equality, we get a full temperature pressure:

The equality denominator (68) is a sum of thermal resistance, which consists of thermal resistance of the thermal conductivity Δ / λ and two thermal resistances of the heat transfer L / α 1 and 1 / α 2.

We introduce the designation

The value K is called heat transfer coefficient.

The inverse heat transfer coefficient is called full thermal heat transfer resistance:

(71)

In the composition of the endocardium distinguish: endothelium, subendothelial layer, muscular-elastic and external connective ones. Endothelium is represented by only one layer of flat cells. The endocardia without a sharp boundary goes to large awarded vessels. Folding valves and flaps of semi-lunk valves are an endocarda duplication.

Motor miocardial fabric

The base of the ventricles, the atrium is removed. Mitral valve left below

Atypical cells of the conductive system, forming and conductive pulses, provide automatism of reducing typical cardiomyocytes. They constitute a conductive heart system.

Thus, in the composition of the muscular shell of the heart, three functionally interconnected devices can be distinguished:

1) contractual, presented by typical cardiomyocytes;

2) reference formed by connective tissue structures around the natural holes and penetrating myocardium and epicard;

3) conductive, consisting of atypical cardiomyocytes - cells of the conductive system.

Structure of the walls of the heart

Heart walls consist of three layers:

endocardium - thin inner layer;
myocardium - fat muscular layer;
epicard is a thin outer layer, which is a visceral leaf of pericardia - a serous heart sheath (cardiac bag).

Endocard wore the heart cavity from the inside, just repeating her complex relief. An endocardium is formed by one layer of flat polygonal endotheliocytes located on a fine basal membrane.

Heart shell Anatomy

A heart. Endocard. Myocardium. Heart structure.

The heart is the central organ of the blood and lymph circulation system. Thanks to the ability to reduce, the heart leads to the movement of blood.

The wall of the heart consists of three shells: endocardium, myocardium and epicarda.

Endocard. In the inner shell of the heart distinguish the following layers: endothelium, linked from the inside of the cavity of the heart, and its basal membrane; subheading layer presented by a loose connective tissue in which many low-influence-renacesed cells; a muscular elastic layer consisting of smooth muscle tissue, between the cells of which elastic fibers are located in the form of a thick network; The outer connective layer consisting of loose connective tissue. Endothelium and sub-hedothelial layers are similar to the inner sheath of blood vessels, the muscular elastic is an "equivalent" of the middle shell, and the outer connective layer is similar to the outer (advential) vessel shell.

The endocardium surface is perfectly smooth and does not prevent the free blood movement. In the atrial stomach region and at the base of the aorta, the endocardia forms duplicatures (folds), called valves. There are distinguished and ventricular and ventricular-vascular valves. In places attaching valves there are fibrous rings. Heart valves are dense fibrous tissue plates covered with endothelium. Endocardium meals occurs by diffusion of substances from the blood in the cavities of atrial and ventricles.

Myocardia ( medium shell Hearts) - a multi-power shell, consisting of across the header muscle tissue, intertensive loose connective tissue, numerous vessels and capillaries, as well as nerve elements. The main structure is the heart muscle tissue, in turn, consisting of cells forming and conducting nerve impulses, and cells of working myocardium, providing a reduction in the heart (cardiomyocytes). Among the cells forming and conductive pulses in the conductive heart system differ three types: p-cells (paiskener cells), intermediate cells and cells (fibers) Purkin.

R-cells - rhythm driver cells are located in the center of the sinus node of the conductive heart system. They have a polygonal form and determined on spontaneous depolarization of plasmolm. Miofibrillas and organelles general meaning In pacemera cells, weakly expressed. Intermediate cells - inhomogeneous group of cells, transmit excitation from p-cells to Purkin cells. Purkin cells - cells with a small amount of miofibrils and the complete absence of the T-system, with a large amount compared to working contracting myocytes with the amount of cyoplasm. Purkin cells transmit excitation from intermediate cells to myocardial contracting cells. They are part of the beam of the GIS of the conductive heart system.

A number of drugs and other factors that can lead to the emergence of arrhythmias and heart blocks are adversely affected by Purkin cells. The presence in the heart of its own conductive system is extremely important because it provides a rhythmic change of systolic abbreviations and diastole chambers of the heart (atrial and ventricles) and the operation of its valve apparatus.

The main mass of myocardium is the contractile cells - cardiac myocytes, or cardiomyocyte. These are the cells of the elongated form with an ordered cross-pre-pre-inspected myofibril system located on the periphery. Between myofibrils are mitochondria with a large number of CRIST. In the myocytes atrium T-system is poorly expressed. Weakly developed in cardiomyocytes granular endoplasmic network. In the central part of myocytes there is a core of oval form. Sometimes there are duid cardiomyocytes. Cardiomyocytes with osmophilic secretory granules containing a sodium-eater peptide are present in the muscle tissue of the atria.

In cardiomyocytes, the inclusions of the glycogen, serving the energy material of the heart muscle, are determined. Its content in myocytes left ventricle is greater than in other heart departments. Myocytes of the working myocardium and conductive system are connected to each other by inserting disks - specialized intercellular contacts. Actin contracting myophilaments are attached in the field of insert discs, there are desmosomomomomas and slotted contacts (Nexus).

The desplaomomomas contribute to the durable adhesion of contracting myocytes into functional muscle fibers, and the nexuss provide the rapid propagation of the plasmolm plasmolm waves from one muscular cell to another and the existence of heart muscle fiber as a single metabolic unit. Characteristic for myocytes of working myocardium is the presence of anastomosing bridges - interrelated fragments of the cytoplasm of muscle cells of different fibers with miofibrils in them. Thousands of such bridges convert the muscle tissue of the heart into a mesh structure capable of synchronously and effectively decrease and throw out the necessary systolic volumes of blood from the cavities of the ventricles. After transferred extensive myocardial infarction (acute ischemic chimshes of the heart wall), when the muscle tissue of the heart is diffuse, the inserting disk system, anastomosing bridges and the conductive system, occur the rhythm of the heart to the fibrillation. In this case, the contractile activity of the heart turns into separate inconsistent twitching of muscle fibers and the heart is not able to dispose of the necessary systolic portions of blood into the peripheral circulation.

Myocardium consists in general from highly specialized cells that have lost the ability to share mitosis. Only in certain areas of atrias are observed mitoses of cardiomyocytes (Rumyantsev P.P. 1982). At the same time, for myocardials, the presence of polyploid myocytes is characterized, which significantly enhances its working potential. Polyploid phenomenon is most often observed in myocardial compensatory reactions, when the load on the heart increases, and during pathology (insufficiency of heart valves, lung diseases, etc.).

Cardiac myocytes in these cases are sharply hypertrophy, and the wall of the heart in one or another department is thickened. In myocardial connective tissue, a richly branched network of blood and lymphatic capillaries is enclosed, which provides permanently working heart muscle and oxygen. In the layers of connective tissue there are dense bugs of collagen fibers, as well as elastic fibers. In general, these connective tissue structures constitute the support skeleton of the heart to which cardiac muscle cells are attached.

The heart is an organ with the ability to automate abbreviations. It can function in certain limits autonomously. However, in the body, the activity of the heart is under the control of the nervous system. In the intramural nerve nodes of the heart there are sensitive vegetative neurons (cells of the p-type cells), small intense fluorescent cells - myth cells and effector vegetative neurons (cells of the 1-th type). Myth cells are treated as inserting neurons.

Epicard - Outdoor Heart Shell - is a visceral leaflet of a chamber bag (pericardium). The free surface of the epicarda is mesotheline as well as the surface of the pericardium facing the pericardial cavity. Under the mesothelium in the composition of these serous shells there is a connecting bowl of loose fibrous connective tissue.

Endocard, Endocardium (see Fig. 704. 709), is formed from elastic fibers, among which connected and smooth muscle cells are located. From the side of the heart of the heart, endockard is covered with endothelium.

The endocard will wipe all the chambers of the heart, faded with the subjective muscular layer, follows all its irregularities formed by fleshy trabeculas, comb, and papilla muscles, as well as their tendon increases.

The vessels of hollow and pulmonary vessels, aortic and pulmonary vessels of hollow and pulmonary vessels, the aorts and pulmonary stem - endocardia passes without sudden boundaries. In the atrium endockard thicker than in the ventricles, especially in the left atrium, and thinner where it covers the puffy muscles with tendon chords and fleshy trabecules.

In the most overdone sections of the walls of the atria, where gaps are formed in their muscular layer, endocardia is close in contact and even grips with epicardia. In the field of fibrous rings of atrocaded-ventricular holes, as well as the holes of the aorta and the pulmonary trunk of the endockard by doubling its sheet - the duplication of the endocardium - forms the sash of the atrocadic valves and the seaside valves of the pulmonary barrel and the aorta. The fibrous connecting tissue between the two sheets of each of the sash and the semi-lone flaps is connected to fibrous rings and thus fixes valves to them.

Heart shell

The heart is located in the near-handing bag - pericardia. The wall of the heart consists of three layers: outer - epicardine, middle - myocardium, and internal - endocardium.

Outer sheath of the heart. Epicard

Epicard is a smooth, thin and transparent shell. It is an internal plate of the shallower bag (pericardium). The connective tissue of the epicardium in different parts of the heart, especially in the furrows and in the top of the top, includes fatty tissue. With the help of the specified connective tissue, epicardy faded with myocardium most tight in places of the smallest cluster or lack of adipose tissue.

Muscular Heart Shell, or Myocardium

The average, muscular sheath of the heart (myocardium), or the heart muscle, is a powerful and large part of the wall of the heart.

There is a dense fibrous fabric between the muscle layer of the atria and the muscular layer, due to which fibrous rings, right and left are formed. From the outside of the outer surface of the heart, their location corresponds to the region of the Vernoy groove.

The right fibrous ring, which surrounds the right atrocadic and ventricular hole, has an oval shape. The left fibrous ring surrounds the left at the vesting hole is not fully: on the right, on the left and behind and has a horseshoe form.

With their front areas, the left fibrous ring is attached to the root of the aorta, forming the connective tissue records of the triangular shape around its rear peripherals - right and left fibrous triangles.

Right and left fibrous rings are interconnected into a common plate, which is completely, with the exception of a small area, isolating the muscles of the atrium from the muscles of the ventricles. In the middle of the connecting ring of the fibrous plate there is a hole through which the muscles of the atrium is connected to the muscles of the ventricles by means of a conductive pulse of a neuromuscular atrial-ventricular beam.

In the circumference of the holes of the aorta and the pulmonary trunk are also interconnected by the fibrous rings; The aortal ring is connected to the fibrous rings of the atrial and ventricular holes.

Muscle sheath atserval

In the walls of the atria distinguish two muscle layers: superficial and deep.

The surface layer is common to both atrial and presents muscle bundles that are mainly in the transverse direction; They are more pronounced on the front surface of the atria, forming a relatively wide muscular layer in the form of a horizontally located interrupted beam, moving to the inner surface of both ears.

On the rear surface of the atria, muscle bundles of the surface layer are in part in the rear partitions.

On the rear surface of the heart, in the gap, formed by the image of the boundaries of the lower hollow vein, the left atrium and the venous sinus, between the bunches of the surface layer of the muscles there is an induction covered with epicardia - a nervous fox. Through this hole, the atrial stems from the rear heart plexus include nerve trunks, which innervate the atrial septum, ventricular partition and the muscular bundle, which connects the muscles of the atrium with the muscles of the ventricles - the preservative bunch.

The deep layer of muscles of the right and left atriality is not common to both atrium. It distinguishes ring-shaped, or circular, and loop-shaped, or vertical, muscle bundles.

Circular muscle bundles in large quantities lie in the right atrium; They are located mainly around the holes of the hollow veins, passing and on their walls, around the cornedic sinuses of the heart, at the mouth of the right ears and the edge of the oval fifth; In the left atrium, they lie mainly around the holes of the four pulmonary veins and the neck of the left ears.

Great muscles are also formed by the deep layer beams. They are most developed on the inner surface of the front-term wall of the right atrium, as well as the right and left ears; In the left atrium, they are less pronounced. In the intervals between the comb's muscles, the wall of the atria and the ears are especially thinned.

On the inner surface of both ears there are very short and thin beams, so-called fleshy crossbars. Crossing in different directions, they form a very subtle loop-shaped network.

Muscle sheath of stomachs

In the muscular shell (myocardium) there are three muscular layers: outdoor, medium and deep. Outdoor and deep layers, moving from one ventricle to another, are common in both ventricles; Middle, although connected with two other, outdoor and deep, layers, but surrounds each ventricle separately.

The outer, relatively thin, layer consists of oblique, part of the rounded, part of the flattened beams. The beams of the outer layer begin at the base of the heart from the fibrous rings of both ventricles and partly from the roots of the pulmonary trunk and aorta. On the front surface of the heart, the outer beams go to the right left, and on the back - from left to right. At the top of the left ventricle, those and other beams of the outer layer form the so-called whirlpool of the heart and penetrate into the depth of the walls of the heart, turning into a deep muscular layer.

The deep layer consists of beams rising from the top of the heart to its base. They have a cylindrical, part of oval shape, are repeatedly cleaved and reinforced, forming different loops. The shorter of these beams do not reach the base of the heart, directly directed from one wall of the heart to another, in the form of fleshy crossbars. The crossbars are located in large quantities throughout the inner surface of both ventricles and have different parts in various sections. Only the inner wall (partition) of ventricles immediately under the arterial holes are deprived of these crossbars.

A number of such short but more powerful muscle beams associated with partly and with an average, and with outer layers, performs in the gastrointestinal cavity freely, forming various magnitudes of the cone-shaped brine muscles.

In the cavity of the right ventricle, three puffy muscles, in the left cavity - two. From the top of each of the papillary muscles, tendon strings begin, with which the puffy muscles are connected to the free edge and partly the lower surface of the three-rigid or mitral valves.

However, not all tendon strings are associated with nobular muscles. The row of them begins directly from the deep muscular layer of fleshy crossbar formed and is attached most often to the lower, ventricular, surface of the sash.

Poofer muscles with tendon strings hold the slad valves when they slam the blood flow heading from abbreviated ventricles (systole) to relaxed atrial (diastole). Meeting, however, obstacles from the valves, blood is not rushed into atrium, but in the hole of the aorta and the pulmonary trunk, the semi-lunged valves of which are pressed the blood current to the walls of these vessels and thereby leave the lumen of the vessels open.

Located between the outer and deep muscle layers, the middle layer forms a number of well-pronounced circular beams in the walls of each ventricle. The average layer is more developed in the left ventricle, so the walls of the left ventricle are much thicker than the right. Bundles of the middle muscular layer of right ventricle are flattened and have almost transverse and somewhat obliquely from the heart base to the top direction.

In the left ventricle, among the beams of the middle layer, it is possible to distinguish beams lying closer to the outer layer and located closer to the deep layer.

The interventricular partition is formed by all three muscular layers of both ventricles. However, muscle layers of the left ventricle take great participation in its formation. Its thickness is almost equal to the thickness of the wall of the left ventricle. She appears in the direction of the cavity of the right ventricle. Throughout 4/5, it represents a well-developed muscular layer. This, significantly large, part of the interventricular partition is called muscle part.

The upper (1/5) part of the interventricular partition is fine, transparent and is called a webbed part. The three-rigid valve is attached to the webcate part.

Musculatory atrial is isolated from ventricular muscles. The exception represents a bunch of fibers, starting in the views of the atria in the region of the cornedic sinus of the heart. This bundle consists of fibers with a large amount of sarcoplasm and a small amount of myofibrils; The beam includes nerve fibers; He takes the beginning of the place of imposition of the lower hollow vein and heads to the partition of the ventricles, penetrating into its thickness. In the beam distinguish the initial, thickened, part, called the atrocadic knot, moving into a thinner barrel - the atrocadic bundle, the beam is sent to the interventricular partition, passes between both fibrous rings and at the upper seat of the muscular part of the partition is divided into the right and left legs. .

The right leg, short and more thin, follows by the partition from the cavity side of the right ventricle to the base of the front puff muscle and in the form of thin fibers (Purkinier) spreads in the muscular ventricular layer.

The left leg, wider and longer right, is located on the left side of the partition of the ventricles, in its initial departments, it lies more superficially, closer to the endocardium. Heading to the base of the papilla muscles, it crumbles on a thin network of fibers forming the front, medium and rear beamextending in myocardium left ventricle.

At the place of the imposition of the upper hollow vein in the right atrium, a sine-atrial node is located between the vein and right ear.

These bundles and nodes, accompanied by nerves and their branching, are a conductive heart system that serves to transmit pulses from one heart separations to others.

Inner heart sheath, or endocard

The inner sheath of the heart, or endocardium, is formed from collagen and elastic fibers, among which there are connective tissue and smooth muscle cells.

From the side of the cavities of the heart, endockard is covered with endothelium.

The endocard will wipe all the cavities of the heart, faded with the subject to the muscular layer, follows all its irregularities, formed by fleshy crossbars, comb, and nobble muscles, as well as their tendon increases.

The vessels of hollow and pulmonary vessels, aortic and pulmonary vessels of hollow and pulmonary vessels, the aorts and pulmonary stem - endocardia passes without sudden boundaries. In the atrium endockard, the thicker than in the ventricles, while it is more thickened in the left atrium, less - where covers the puffy muscles with tendon strings and fleshy crossbars.

In the most overdone sections of the walls of the atria, where in the muscular layer they are formed by gaps, endocardia is contacting close and even grips with epicardia. In the region of fibrous rings, atrial and ventricular holes, as well as the holes of the aorta and the pulmonary trunk of the endocardium by doubling its sheet, duplication of the endocardium, forms the sash of the mitral and three-rolled valves and the seaside valves of the pulmonary barrel and aortic. The fibrous connecting tissue between the two sheets of each of the flaps and the seal valves is connected to the fibrous rings and thus fixes the valves to them.

Okolosraid bag, or pericardium

The shallower bag, or pericardium, has the shape of a slant cut cone with a lower base located on a diaphragm, and a vertex that gives almost to the level of corner of the sternum. In width, it spreads more on the left side than the right.

In the window, the bag is distinguished: the front (sternum-rib) part, the back-haired (diaphragmal) part and the two side - right and left - medioched parts.

The breast-rided portion of the window-shaded bag is facing the front breast wall and is located, respectively, the body of the sternum, V-Vi rib cartilage, intercostal gaps and the left section of the sword-shaped process.

The side sections of the breast-rib part of the window-shaped bag are covered with the right and left sheets of meduated pleura separating it in the front areas from the front of the chest wall. Sections of mediated pleura covering pericardium are allocated under the name of the otolosraid part of the mediated pleura.

The middle of the breast-ribbed part of the bag, the so-called free part, is open in the form of two triangular intervals: upper, smaller, corresponding to the fork gland, and the lower, greater, corresponding to the pericardium, facing its bases upward (to the cutting of the sternum) and the book (to the diaphragm ).

In the region of the upper triangle, the breast-riding part of the pericardia is separated from the sternum by a loose connective and a fatty tissue, in which children laid a fork iron. The compacted part of this tissue is formed by the so-called upper breast-shallower ligament, which fixes the front wall of the pericardium to the sternum handle.

In the region of the lower triangle pericardium is also separated from the sternum with a loose fiber, in which the compacted part is distinguished, the lower sternum-olocroser adequate ligament, which fixes the lower part of the pericardium.

In the diaphragmal part of the window, the top department is distinguished by the upper section, participating in the formation of the front border of the rear mediastinum, and the lower section covering the diaphragm.

The top department is adjacent to the esophagus, the chest aorta and the unpaired vein, from which this part of the pericardium is separated by a layer of loose connective tissue and a thin fascial leaflet.

The lower part of the same part of the pericardium, which is its basis, grows tightly with the tendral center of the diaphragm; slightly extending to the front sections of its muscular part, it is connected to them with a loose fiber.

The right and left mediochang parts of the oololoral bag are adjacent to the mediated pleura; The latter is connected to the pericardium with a loose connective tissue, and it may be a thorough preparation of separated. In the thicker of this loose fiber connecting the mediocked pleura with pericardium, the diaphragmal nerve passes and the sampling vessels.

Pericardium consists of two parts - internal, serous (serous necroserous bag) and outer, fibrous (fibrous olive-sharing bag).

The serous necroserous bag consists of two as if nested one in other serous bags - an outdoor, freely surrounding heart (serous bag of pericardia actually), and internal - epicarda, faded with myocardium. The serous cover of the pericardium is an overwhelling plate of the serous sulfuric bag, and the serous cover of the heart is an internal plate (epicard) of the serous oolery bag.

The fibrous oollady bag, which is especially expressed on the front wall of the pericardium, fixes the shallower bag to the diaphragm, the walls of large vessels and through the bundles to the inner surface of the chest.

Epicard turns into pericardium on the base of the heart, in the field of intensity of large vessels: hollow and pulmonary veins and the exit of the aorta and the pulmonary trunk.

Between the epicardium and pericardium there is a slick-shaped form (cavity of the window bag), containing a small amount of fluid of the necrord, which wets the serous surfaces of the pericardium, causing it during the heart abbreviations of a single serous plate on another.

As it was indicated, the s servos of the serous oolement bag is switched to an internal plate (epicard) at the place of imposition and exit from the heart of large blood vessels.

If, after removal of the heart, it is located large vessels in relation to the pericardium from the inside with respect to the pericardium at approximately two lines - right, more vertical, and left, somewhat inclined. On the right line, the top hollow vein, two right pulmonary veins and lower veins, on the left line - aorta, the pulmonary barrel and two left pulmonary veins are locked.

There are several different shapes and sinuses on the site of the epicarda transition to the napkin plate. The largest of them are the transverse and oblique sinuses of the shallower bag.

Cross sinus shallower bag. The initial departments (roots) of the pulmonary barrel and the aorta, nourishing one to another, are surrounded by a common leaflet of epicarda; The hide from them is atrium and near the right - the upper hollow vein. Epicard on the side of the rear wall of the initial departments of the aorta and the pulmonary trunk moves up and back to the atrium located behind them, and from the last - down and forward again on the base of the ventricles and the root of these vessels. Thus, there is a passage between the aorta's root and the pulmonary barrel of the front and the atriums at the front of the front, the sinus is well visible when pulling the aorta and the pulmonary trunk of the Kepent, and the upper hollow vein is the stop. This sinus is limited from above Pericardia, rear - the upper hollow vein and the front surface of the atria, in front - aorta and a pulmonary barrel; On the right and on the left, the transverse sinus is open.

Oblique sinus of the window bag. It is located below and behind the heart and represents the space bounded front to the epicardine's rear surface of the left atrium, rear - rear, mediated, part of the pericardium, on the right - the bottom of the vein, on the left - the pulmonary veins, also covered with epicardium. In the upper blind pocket of this sinuse there is a large number of nerve nodes and heartband stems.

Between the epicardine covering the initial part of the aorta (to the level of leaps of the shoulder barrel), and a small magnitude of his pocket is formed on this place on this place on this place - aortic protrusion. On the pulmonary trunk, the epicardus transition to the specified closed plate occurs at the level (sometimes below) arterial ligament. On the upper floor of Vienna, this transition is below the location of the unpaired vein. On the pulmonary veins, the transition site almost reaches the gate of the lungs.

On the posterior wall of the left atrium, between the left upper pulmonary vein and the base of the left atrium, it takes place to be left to the right of the shallower bag, the so-called fold of the upper left half of the vein, in the thickness of which the oblique vein of the left atrium and the nervous plexus.

Structure of the wall of the heart

The wall of the heart consists of three layers: outer - epicardium, medium-myocardium and internal - endocardium.

Outer sheath of heart

Epicard, Epicardium (see Fig. 701, 702, 721), is a smooth, thin and transparent shell. It is a visceral plate, Lamina Visceralis, Pericarda, Pericardium. The connective tissue of the epicardium in different parts of the heart, especially in the furrows and in the top of the top, includes fatty tissue. With the help of connective tissue, Epicard faded with myocardium most tight in places of the smallest cluster or lack of adipose tissue (see "Pericard").

Muscular heart sheath

Muscular heart sheath, or myocardium. Middle, muscular, heart sheath, Myocardium (see Fig. 703, 704, 705, 706, 707, 710, 709, 710, 711, 712, 713, 714), or heart muscle, is a powerful and significant part of the thickness Heart walls. The greatest thickness of myocardium reaches in the region of the left ventricular wall (11-14 mm), twice the thickness of the wall of the right ventricle (4-6 mm). In the walls of the atria, myocardium is developed significantly less and the thickness of it here is only 2-3 mm.

There is a dense fibrous fabric between the muscle layer and the muscular layer of ventricles, due to which fibrous rings, the right and left, Anuli Fibrosi, Dexter ET SINISTER are formed (see Fig. 709). From the side of the outer surface of the heart, their location corresponds to the Vernoy Broker.

The right fibrous ring, Anulus Fibrosus Dexter, which surrounds the right atrial and ventricular hole, has the form of an oval. The left fibrous ring, Anulus Fibrosus Sinister surrounds the left at the vestricular hole on the right, on the left and behind and in the form of a horseshoe.

With its front sites, the left fibrous ring is attached to the root of the aorta, forming a triangular connective tissue plates around its rear peripherals - right and left fibrous triangles, Trigonum Fibrosum Dextrum et trigonum fibrosum sinistrum (see Fig. 709).

In the circumference of the holes of the aorta and the pulmonary trunk (see Fig. 709) are also interconnected fibrous rings; The aortal ring is connected to the fibrous rings of atrial and ventricular holes.

Muscle sheath atserval

In the walls of the atria distinguish two muscle layers: superficial and deep (see Fig. 710).

On the rear surface of the atria, muscle bundles of the surface layer are in part in the rear partitions. On the rear surface of the heart, between the beams of the surface layer of the muscles, there is an epicardine-covered groove, bounded by the mouth of the lower hollow vein, the projection of the interpreservation septum and the mouth of the venous sine (see Fig. 702). At this site, the atrial stems include nervous trunks, which innervate the atrial septum and the ventricular partition, is an atrief-ventricular beam (Fig. 715).

The deep layer of muscles of the right and left atriality is not common to both atrium. It distinguishes circular and vertical muscle bundles.

Circular muscle bundles in large numbers lie in the right atrium. They are located mainly around the holes of the hollow veins, turning onto their walls, around the coronary sinus of the heart, at the mouth of the right ears and the edge of the oval fifth; In the left atrium, they lie mainly around the holes of the four pulmonary veins and at the beginning of the left ears.

Great muscles, mm. Pectinati is also formed by the deep layer beams. They are most developed on the inner surface of the ending the wall of the cavity of the right atrium, as well as the right and left ears; In the left atrium, they are less pronounced. In the intervals between the comb's muscles, the wall of the atria and the ears are especially thinned.

On the inner surface of both ears there are short and thin beams, so-called fleshy trabecules, TRABECULAE CARNEAE. Crossing in different directions, they form a very subtle loop-shaped network.

Muscle sheath of stomachs

In the muscular shell (see Fig. 711) (myocardium) distinguish three muscle layers: outdoor, medium and deep. Outdoor and deep layers, moving from one ventricle to another, are common in both ventricles; The average, although connected with two other layers, surrounds each ventricle separately.

The outer, relatively thin layer consists of oblique, part of the rounded, part of the bleached beams. The beams of the outer layer begin at the base of the heart from the fibrous rings of both ventricles and partly from the roots of the pulmonary trunk and aorta. On the chest-rib (front) surface of the heart, the outer beams go to the right left, and on the diaphragmal (bottom) - from left to right. At the top of the left ventricle, those and other external oslo bundles form the so-called heart curl, Vortex Cordis (see Fig. 711, 712), and penetrate into the depth of the walls of the heart, turning into a deep muscular layer.

A number of such short but more powerful muscle beams associated with partly and with an average, and with an outer layer, performs in the gastrointestinal cavity freely, forming various magnitude of cone-shaped puffy muscles (see Fig. 704, 705, 707).

The interventricular partition, septum interventriculare (see Fig. 704), is formed by all three muscular layers of both ventricles, but more muscle layers of the left ventricle. The thickness of the partition is reached, a slightly yielding the thickness of the left ventricular wall. The interventricular partition is convex towards the cavity of the right ventricle and for 4/5 represents a well-developed muscular layer. This significantly most of the interventricular partition is called the muscular part, Pars Muscularis.

The top (1/5) part of the interventricular partition is a webbed part, Pars Membranacea. The scene of the right atrial and ventricular valve is attached to the connecting part.

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Intestines

Intestine (Intestinum) is the largest part of the digestive tube, which originates from the gastroincing of the stomach and ends with a rear-ground opening. The intestine is involved not only in digestion of food, her assimilation, but also in the development of many biological substances, for example, hormones playing a significant role in the immune status of the body.

Its length is an average of 4 meters in a living person ( tonic Condition), and from 6 to 8 meters in an atonic state. In children in the neonatal period, the bowel length reaches 3.5 meters, increasing in the first year of life by 50%.

The intestine undergoes changes with age. So, changes its length, form, location. More intense growth is observed from 1 to 3 years, when the child goes with breastfeeding On the shared table. Intestinum diameter increases significantly for the first 24 months of life and after 6 years.

The length of the small intestine in the newborn is equal to 1.2 to 2.8 meters, in an adult from 2.3 to 4.2 meters.

The growth of the body affects the location of its loops. The duodenum in infants has a semicircular shape, located at the level of the first lumbar vertebra, going down to the 12-year age of up to 3-4 lumbar vertebrae. Its length does not change from birth to 4 years old, and is equal to 7 to 13 cm, in children over 7 years old around the duodenum formation formed fat deposits, as a result it becomes more or less fixed and less mobile.

After 6 months of life, the newborn can notice the difference and division of the small intestine into two departments: skinny and iliac.

Anatomically, the entire intestine can be divided into thin and thick.

The first thing after the stomach is the delicious intestine. It is in it that digestion takes place, suction of some substances. The name has received due to smaller diameter compared to the subsequent digestive pipes.

In turn, the delicate intestine is divided into duodenum (duodenum), skinny, iliac.

The underlying digestive tract departments are called a fat intestine. The processes of suction of most substances and the formation of Himus (Cashier from dyeing food) occur here.

The entire thick intestine has a more developed muscular and serous layers, a larger diameter, which is why they were called.

blind intestine (Caecum) and appendix, or a worm-shaped process;
rimming, which is divided into ascending, transverse, descending, sigmoid;
straight intestine (has departments: ampoule, rear-rose channel and anus).

Parameters of different departments of the digestive tube

The delicious intestine (Intestinum Tenue) has a length of 1.6 to 4.3 meters. In men, she is longer. The diameter of it gradually decreases from the proximal to the distal part (from 50 to 30 mm). Intestinum Tenue lies intraperitoneally, that is, intraperitoneally, her mesentery is a duplication of peritoneum. Leaflets of mesenter are covered with blood vessels, nerves, lymph nodes and vessels, fatty tissue. Intestinum Tenue cells produced a large number of enzymes that take part in the process of digesting food together with the enzymes of the pancreas, except for this all medicines, toxins, with them oral reception They are suused here.

COLON Length is relatively less - 1.5 meters. Its diameter decreases from the beginning to the end from 7-14 to 4-6 cm. As described above, it has 6 divisions. Caecum has a growing rudimentary body, Appendix, which, in the opinion of most scientists, is an important component of the immune system.

Throughout Colon, there are anatomical bends. This is the place of transition of one part of it to another. Thus, the transition of ascending into the transverse colon received the name of the hepatic bending, and the spleen bending form transverse downstream departments.

The rank of intestines at the expense of mesenteric arteries (top and bottom). The outflow of venous blood is carried out according to the veins of the same name, which make up the basin of the portal vein.

Innervates intestines with engine and sensitive wipes. The motor belongs to the spinal and branches of the wandering nerve, and to the sensitive - the fiber of the sympathetic and parasympathetic nervous system.

Duodenum (duodenum)

Starts from the gatekeeper zone of the stomach. It is an average length of 20 cm. It bypasses the head of the pancreas in the form of the letter C or horseshoe. This anatomical education is surrounded by important elements: common bile duct And the liver with a portal vein. The loop formed around the pancreas head has a complex structure:

Exactly top part Forms a loop, starting at the level of 12 breast vertebra. It smoothly goes into the descending, its length is not more than 4 cm, then it goes almost parallel to the spinal column, reaching up to 3 lumbar vertebra, turns to the left. So the lower bending is formed. Downward Duodenum on average up to 9 cm. There are also important anatomical entities for it: the right kidney, a common bull duct and liver. Between the descending duodenum and the head of the pancreas runs the groove, in which there is a common bull. In the course, it is reunited with the pancreatic duct and on the surface of a large nipple flows into the cavity of the digestive tube.

The next part is horizontal, which is located horizontally at the level of the third lumbar vertebra. She will fit to the bottom of Vienna, then gives rise to ascending Duodenum.

Ascending Duodenum short, no more than 2 cm, it turns sharply and goes into Jejunum. This small bend is called twelve-dimensional, attached to a diaphragm with muscles.

Ascending Duodenum passes near the mesenteric artery and vein, the abdominal department of aorta.

The location of it is almost all over the retroperitoneal, except for its ampular part.

Skinny (Jejunum) and iliac (Ileum)

Two Intestinum departments that have almost the same structure, so they often describe them together.

Jejunum loops are located in the abdominal cavity to the left, it covers it from all sides Seriza (peritone). Anatomically, Jejunum and Ileum are part of the mesenteric part of Intestinum Tenue, they have a well-pronounced serous shell.

Special differences in the anatomy Jejunum and Ileum has no. The exception is a larger diameter, thicker walls, noticeably greater blood supply. The mesenteric part of the small intestine almost all over the entire length is covered with a bowl.

The length of Jejunum to 1, 8 meters in tonic voltage, after death, it relaxes and increases up to 2.4 meters long. The muscular layer of its walls provides abbreviations, peristaltics and rhythmic segmentation.

Ileum is separated from a blind special anatomical formation - a baguinium flap. It is also called the ileocecal valve.

Jejunum takes the lower floor of the abdominal cavity, flows into the Caecum in the field of the iliac yam on the right. It is completely covered with peritoneous. Its length from 1.3 to 2.6 meters. In an atonic state, it is capable of stretching to 3.6 meters. Among its functions in the first place are digesting, food suction, its promotion in subsequent Intestinum departments with peristaltic waves, as well as the development of neurotenzine, which is involved in the regulation of drinking and food behavior of a person.

Blind intestine (Caecum)

This is the beginning of the large intestine, Caecum is covered with peritoneal on all sides. It resembles a bag of a bag that has a long and diameter almost equal (6 cm and 7-7.5 cm). Caecum is located in the right iliac hole, on both sides is limited by sphincters whose functions are to ensure one-sided current of the chimus. On the border with Intestinum Tenue, this sphinker is called Bauginiyev's valve, and on the blind and colon - buzze sphincter.

It is known that Appendix is \u200b\u200ba Caecum process, which departs just below the ileocecal angle (the distance ranges from 0.5 cm to 5 cm). It has a distinctive structure: in the form of a narrow tube (diameter up to 3-4 mm, length from 2.5 to 15 cm). Through a narrow hole, the process is reported to the cavity of the intestinal tube, besides, it has its own mesenter connected to a blind and ileum. Usually, Appendix is \u200b\u200blocated almost all people typically, that is, in the right iliac region, and a free end reaches a small pelvis, sometimes falls below. There are also atypical locations that rarely meet and deliver difficulties during operational intervention.

The structure and functions of the small intestine

The delicious intestine is a tubular organ of the digestive system in which the transformation of the food lump in a soluble connection continues.

The structure of the organ

The small intestine (Intestinum Tenue) departs from the gastric gatekeeper, forms a lot of loops and goes into a thick bowel. In the initial department, the intestinal circle is 40-50 mm, at the end of 20-30 mm, the intestinal length can reach up to 5 meters.

The duodenal intestine (duodenum) is the shortest (25-30 cm) and a wide part. It has the shape of the horseshoe, in length is comparable to 12 fingers wide, due to which it received its name;
Skinny intestine (length 2-2.5 meters);
Iliac (length 2.5-3 meters).

The wall of the small intestine consists of the following layers:

The mucous membrane - lins the inner surface of the organ, 90% of its cells are enterocytes that provide digestion and suction. It has relief: Vile, circular folds, crypts (tubular protruding);
The own plate (submembricted layer) is the accumulation of fat cells, there are also nervous and vascular plexuses;
Muscular layer - formed by 2 shells: circular (internal) and longitudinal (external). Between the shells there is a nervous plexus that controls the reduction of the intestinal wall;
Serous layer - covers the delicate intestine from all sides, with the exception of Duodenum.

The blood supply to the small intestine is carried out due to the hepatic and mesenteric arteries. Innervation (supply nerve fibers) It comes from the plexus of the autonomic nervous system of the abdominal cavity and the wandering nerve.

Digestion process

The following digestion processes occur in the small intestine:

To digest the food lump, the intestine produces the following enzymes:

Erepsin - splits peptides to amino acids;
Enterocinate, trypsin, kinaseogen - breaking simple proteins;
Nuclease - digested complex protein compounds;
Lipase - dissolves fats;
Lactose, amylase, maltose, phosphatase - cleaved carbohydrates.

The slim intestine mucosa produces 1.5-2 liters of juice per daywhich consists of:

The subtle intestine produces the following hormones:

Somathosotatin - prevents garbage release (hormone, which enhances the release of digestive juices);
Secretin - regulates the secretion of the pancreas;
Vazointsinal peptide - stimulates blood formation, affects smooth muscles in the intestine;
Gastrin - participates in digestion;
Motilin - regulates intestinal motor activity);
Cholecystokinin - causes a reduction and emptying of the gallbladder;
Gastroincing polypeptide - slows down the selection of bile.

Functions of the small intestine

The basic functions of the body include:

Secretor: produces intestinal juice;
Protective: mucus contained in intestinal juice protects the walls of the intestine from chemical influences, aggressive stimuli;
Digestive: splits the food lump;
Motor: Due to the muscles, Hamus movement (liquid or semi-liquid content) is moving along the small intestine, stirring with gastric juice;
Suction: The mucous membrane absorbs water, vitamins, salts, nutritious and medicinal substanceswhich are distributed throughout the body through lymphatic and blood vessels;
Immocompetent: prevents the penetration and reproduction of conditionally pathogenic microflora;
Removes toxic substances, slags from the body;
Endocrine: produces hormones that affect not only the process of digestion, but also to other organism systems.

Diseases of the small intestine:

Enteritis;
Celiac disease.

The structure of the thin and large intestines for dummies

Gathered Write a review about a new species surgical operations on the intestines, but thought it was first to tell about structure of this intestine. When I studied at school, sometimes I was confused which intestine for which one goes. Therefore, today I eliminate this gap. You will even learn what kind of intestine hungry and why.

See also: Where is the intestine and where the stomach

Will be a brief course of anatomyGet ready. Unnecessary threw out here - only the most interesting thing.

Intestine man consists of two departments - thin and thick. Why called so? The diameter of the small intestine at the beginning is 4-6 cm and gradually decreases up to 2.5-3 cm. Thick intestine has medium diameter 4-10 cm. By appearance They will differ even a two-year student, but about it below.

(Names of English, although they look like Latin)

Small Intestine - small intestine.

Colon - colon (part of the large intestine).

Rectum - rectum.

When this material was preparing, it was almost confused: in textbooks are given different figures about the length of the small intestine. The attempt is simple: in living man's length of the small intestine is 3.5 - 4 meters, but in the dead - about 6-8 M. Due to the loss of the tone of the intestine, that is, 2 times more. Length of Tolstoy Intestinal much less - 1.5 - 2 meters.

Small intestine

The delicious intestine has 3 Departments:

12rine (Lat. Duodenum, read "Douroanum", emphasis is everywhere on the penultimate syllable, if I have not allocated otherwise): the initial division of the small intestine, has the shape of the letter "C" and length 25-30 cm (21 cm in a living person), envelopes the head of the pancreas, fall into it common bull and chief pancreatic dashing (Sometimes there is an additional pancreatic duct). The name is given according to the length of this intestine, which ancient anatomas measured on the fingers (I did not use the rules). The finger in antiquity in Russia was called finger ("Index finger").
jejunum (Jejunum, Eyunum - empty, hungry): is upper half small intestine. You did not have a question why the intestine called " hungry"? Just at the autopsy, she often turned out to be empty.
ileum (Ileum, Ileum - from Greek. Ileos twist): is lower half small intestine. There is no clear boundary between the skinny and the iliac intestine, and they themselves are very similar in appearance. Therefore, the anatomas agreed that top 2/5 fine intestine - this is jejunum, but lower 3/5 - Ileum. Consider the length in meters themselves.

Departments of the small intestine Latin.

Duodenum - 12-Person intestine.

Jejunum - skinny intestine.

Ileum - iliac intestine.

Inflammation of the 12-rosewoman is called duodenitis (heard the term gastroduodenit?). In practice, the inflammation of the skinny and iliac intestine is not separated separately, but called a common term enteritis (inflammation of the small intestine) from Greek enteron. - intestines.

Typical microscopic structure Intestinal wall such (from the inside of the duck):

mucous membrane
sublimated base
muscular layer:
- internal circular (circular),
- the outer longitudinal (in the thick intestine, only three ribbons remain, about them below),
serous (outer) layer.

Layers of the intestinal wall

(Latin Word Pronunciation See in brackets, others - in the English-Russian dictionary)

mucosa (Mukoza) - mucous membrane,

submucosa (submucosis) - submembrance,

muscularis (Musculaaris) - muscular layer (Inner - internal, Outer - external),

serosa (Serose) - serous shell (here is a peritoneum),

Mesentery (Mesenterium, Mesenierium) is a forehead of the peritoneum, which attaches the intestines to the back of the abdominal cavity; It takes vessels and nerves. You can compare the structure of the intestinal wall with the structure of the wall of the esophagus, which I wrote earlier in the article on poisoning with acetic essence.

Colon

Go to K. tolstoy intestine. One of the favorite questions on the anatomy is to call external differences of the large intestine from thin. They are 5, if I did not forget:

grayish color
large diameter
the presence of three longitudinal muscular tapes (this is what remained from the longitudinal muscular layer of the wall),
availability swims (wall protrusion) - Gaustrum,
availability salnikovyehrovkov (Fat letters).

Features of a fat intestine

(clockwise from its start)

Ileum - iliac,

Vermiform Appendix - Cherry Process (Appendix),

CECUM - blind intestine,

IleoCecal Valve - Ileocecal valve,

Superior Mesentteric Artery - Upper mesenteric artery,

Right Colic Flexure - right rim bending,

TRANSVERSE MESOCOLON - a mesentery of the transverse colon,

Left Colic Flexure - left rim bending,

Epiploic Appendages - fat letters,

Tenia Coli - muscle ribbon.,

Inferior Mesentteric Artery - Lower mesenteric artery,

Sigmoid Mesocolon - a mesentery of a sigmoid bowel,

Rectum - direct intestine,

Anal Canal - anal canal.

Colon He has several departments:

cecum (CECUM or CAECUM, CEKUM): Length 1 - 13 cm; This is a portion of a thick intestine below the imposition of the ileum, that is, below the ileocecal valve. From the place of convergence of the Three Tapes, a worm-shaped process (appendix) is departed, which can be directed not only down, but also in any other way.
ascending colon (Colon Ascendens, Colon Assendens)
cross colon (Colon Transversum, Colon Transviersum)
downward collapse (Colon Descendens, Colon Daescendens)
sigmoid colon (Colon Sigmoideum, Colon Sigmoidaum): The length is very variable, up to 80-90 cm.
rectum (Rectum, Racktum): Length 12-15 cm. Diseases of this intestine are engaged in doctors of a separate specialty - proctologists (from Greek. Proktos - rear pass). The structure of the rectum will not describe here, it is a difficult topic.

Departments of the Tolstoy Intestine (in order)

cECUM - cecum,

ascending Colon - ascending colon,

tRANSVERSE COLON - cross colon,

descending Colon - downward collapse,

sigmoid Colon - sigmoid colon,

rectum - rectum.

I told the structure of the intestine in a simplified form. Students are taught more: how to cover trousers, have a mesentery, as blood supply to which it borders and so on.

The inflammation of the large intestine is called colitis. The inflammation of the rectum should be called damn, but such a term is rarely used. More often used paraprotit - Inflammation of fiber around the rectum (pair - about).

Update from 29.02.2008. The inflammation of the blind intestine is called typhlitis (from Greek. Typhlon - blind intestine). You will hardly need a name, but I added here for the encyclopedicity of the presentation.

What is interesting: the thin and large intestines differ not only in structure and functions. They are sick in different ways. Diarrhea (diarrhea) in enteritis in appearance sharply different from diarrhea with colitis. But about it somehow another time. If you are interested to read. 🙂

It is he who protects our engine from injuries, the penetration of infections, carefully fixes the heart in a certain position in the chest cavity, preventing its displacement. Let's talk more about the structure and functions of the outer layer or pericardia.

1 Cardiac layers

Muscular heart sheath

2 Delete into the outer layer

Structure of the wall of the heart

The following departments or walls in the surface pericardial layer are distinguished, their name depends directly from the organs and sections to which the shell arrive. Pericarda walls:

Pericard front wall. Goes to the chest wall
Diaphragm wall. Directly fasten with a diaphragm This wall of the shell.
Side or pleural. It is isolated on the sides of the mediastinum, fit to the Light Plegre.
Rear. It borders with the esophagus, downward aorta.

3 Why the heart of the bag?

Pericard and its structure

4 When "sick" Pericard

Pericarditis - Inflammation of the Owl Bag

Not rare pericarditis accompanies mediastinal tumor processes. Depending on whether many liquid is released into the pericardial cavity during inflammation, they allocate dry and discharge form of the disease. Often these forms are precisely in such a manner with each other with the course and progression of the disease. Dry cough, chest pain, especially with deep breath, changing body position, during cough is characteristic of dry form of the disease.

The discharge form is characterized by a certain decrease in pain sharpness, and the same time appears the sad severity, shortness of breath, progressive weakness. With proven population in the cavity of the pericardia, the heart turns out to be siled in vice, a normal ability to reduce is lost. Dyspnea pursues the patient even alone, active movements become and not possible at all. The risk of tamponade of the heart is growing, which threatens with a fatal outcome.

5 injection in heart or pericardial puncture

Aortity aneurysm Hearts - what is it?

Bradycardia heart what it is

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Structure of the wall of the heart.

The inner structure of the heart.

Human heart has 4 chambers (cavities): two atrium and two ventricles (right and left). One camera is separated from another partitions.

Cross partition Share the heart on the atrium and ventricles.

Longitudinal partition In which two parts are distinguished: the interprisence and interventricular, shares the heart to the unlocking two halves - the right and left.

In the right half there is the right atria and the right ventricle and the venous blood flows

In the left half there is a left atrium and left ventricle and flowing arterial blood.

There is an oval fossa on the inter-subsequent partition of the right atrium.

The following vessels fall in the atrium:

1. Upper and lower hollow veins

2. The smallest veins of the heart

3. Hole of the Vernial Sine

On the bottom wall This atrium is located the right atrocadic hole, in which there is a three-rolled valve that prevents the reverse current of blood from the ventricle in the atrium.

Right ventricle is separated from the left interventricular partition.

In the right ventricle distinguish two departments:

1) front, in which there is an arterial cone, passing into the pulmonary trunk.

2) rear (Actually the cavity), there are fleshy trabecules, passing into the nobble muscles, tendon chords (threads) are departed from them, heading towards the sashs of the right atrocarditant valve.

4 pulmonary veins fall into it, according to which arterial blood flows. On the lower wall of this atrium there is a left atrocaded-ventricular hole in which a two-rolled valve (mitral) is located.

Left ventricles two departments:

1) front departmentwhich takes the beginning of the aorta cone.

2) rear department (Actually the cavity), there are fleshy trabecules, passing into the nobble muscles, tendon chords (threads) are departed from them, heading towards the left atreservant valve flaps.

Distinguish two types of valves:

1. Folded valves are two and three-rissed.

Double valve Located in the left atreservantic hole.

Three-profile valve Located in the right atreat and ventricular hole.

The structure of these valves is the following: The valve flap is connected to the help of chord with nobble muscles. Reducing, the muscles stretch the chords, the valves open. When the muscles relax, the valves are closed. These valves prevent the reverse current of blood from the ventricles in the atrium.

2. Alley valves are together together the output of the aorta and the pulmonary trunk. They interfere with the stream of blood from the vessels in the ventricles.

There are valves of three semi-luncture dampers - pockets, in the center of which there is thickening - nodules. They provide complete sealing when closing the semi-lunged valves.

The wall of the heart consists of three layers: internal - endocardium, medium, thick - myocardium and outdoor - epicarda.

1. The endocarde widespread from the inside of all the cavities of the heart, covers the papilla muscles with their tendon chords (threads), forms the atrocadic and ventricular valves, the aortic valves, the pulmonary trunk, as well as the damper of the lower hollow vein and the coronary sinus.

It consists of connective tissue with elastic fibers and smooth muscle cells, as well as endothelium.

2. Myocardium (Muscular Layer) is a heart-cutting apparatus. The myocardium is formed by cardiac muscular cloth.

Atrial muscles are completely separated from the muscles of the ventricles with the help of fibrous rings arranged around atreservant and ventricular holes. Fibrous rings, together with other braces of fibrous tissue, constitute a kind of skeleton of the heart, serving muscle support and valve apparatus.

Atrial muscular shell consists of two layers: Surface and deep. It is thinner of the muscular shell of ventricles consisting of three layers: internal, medium and outdoor. At the same time, the muscular fibers of the atria do not go into muscle fibers of the ventricles; Atrium and ventricles are reduced undesigned.

3. Pichard is the outer sheath of the heart that covers his muscle and faded with it. At the base of the heart, epicard is wrapped and passes into pericardium.

Pericardine is a near-smooth bag, an insulating heart from the surrounding organs, protects against excessive stretching.

Pericarde from the inner visceral plate (epicarda) and the outer parietal (cloth) plate.

Between two records of pericardia - parietal and epicardia there is a slick-free space - the pericardial cavity, in which there is a small amount (up to 50 ml) of a serous fluid that reduces the friction in heart abbreviations.

Structure of the walls of the heart

endocardium - thin inner layer;
myocardium - fat muscular layer;
epicard is a thin outer layer, which is a visceral leaf of pericardia - a serous heart sheath (cardiac bag).

The middle layer of the heart wall is formed from

Answers and explanations

Heart walls consist of three layers:

endocardium - thin inner layer; Myocardium - fat muscular layer; Epicard is a thin outer layer, which is a visceral leaf of pericardia - a serous heart sheath (cardiac bag).

Endocard wore the heart cavity from the inside, just repeating her complex relief. An endocardium is formed by one layer of flat polygonal endotheliocytes located on a fine basal membrane.

133. Heart wall layers, their functions.

Heart, Cor (Greek Cardia), is a hollow organ, the walls of which consist of three layers - internal, medium, outdoor.

Medium shell, Myocardium, Myocardium is formed by the worn muscle cells (cardiomyocytes). Provides a reduction in atria and ventricles.

Outer shell, Epicard, Epicardium is represented by a serous shell, which is a visceral leaflet of pericardia. The shell provides a free shift of the heart when it is reduced.

134. The degree of severity of the muscular layer in the heart chambers.

The muscular layer has a different thickness in the heart chambers, which depends on the work performed by them. The greatest thickness of this layer - in the left ventricle, because It provides blood movement over a large circulation of blood circulation, overcoming huge friction forces. In second place is the thickness of the myocardium in the wall of the right ventricle, providing blood flow through a small circulation of blood circulation. And finally, this layer is least expressed in the walls of the atria, ensuring the movement of blood from them in the ventricles.

135. Features of the structure of the myocardium of ventricles and atrium.

The atrium myocardium consists of two layers: surface - Total for both ventricles and deep - Separate for each of them.

In the ventricles myocardium consists of three layers: outdoor (superficial), medium and internal (deep).

The outer and internal layers are common to both ventricles, and the middle layer is separate for each ventricle. Muscle fibers atrial and ventricles are isolated from each other.

Derivatives of the deep layer of the myocardial of ventricles They are puffy muscles and fleshy trabecules.

Derivatives of the outer layer of the myocardial atrial Great muscles are.

136. Big and small circles circulation, their functions.

137. Heart valves, their functions.

There are four valves in the heart: two folded and two semi-short.

Right atrial and ventricular (three-rolled) valve Located between the right atrium and the ventricle.

Left atrial and ventricular (mitral) valve Located between the left atrium and the ventricle.

Valve of the pulmonary trunkValva Trunci Pulmonalis is located within the base of the pulmonary trunk.

Aorti valveValva Aortae is located within the base of the aorta.

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Structure of the wall of the heart

endocard middle - myocardium outdoor epicard.

Endocard -

Myocardia -

superficial layer outer longitudinal, middle Ring I. interior

Fibrous rings

conductive system sinuo-forever

2) preservative knot

Epicard pericardium

Blood supply

Structure of the wall of the heart

Anatomy-physiological features of the cardiovascular system

The circulatory system consists of a heart - the central blood circulation body, the rhythmic reduction of which causes this movement, and vessels. The vessels on which blood from the heart enters the organs is called - arteries, and blood vessels that bring blood to hearts - veins (Fig. 3).

Heart - hollow muscle body massigr., Cone-shaped. Located in the chest cavity between the lungs, in the lower mediastinum.

In the chest cavity, the heart occupies oblique position and draws its a wide part - the base to the top, back and right, and narrow - top, forward, down and left; On 2/3 it is located in the left half of the chest cavity.

Figure 3 - Heart; lengthwise cut.

1 - top hollow vein; 2 - right atrium; 3 - Right atrial and ventricular valve; 4 - right ventricle; 5 - interventricular partition; 6 - left ventricle; 7 - Peduced muscles; 8 - tendon chords; 9 - left at the velocity valve; 10 - left atrium; 11 - pulmonary veins; 12 - Aortic arc.

The boundaries of the heart change and depends on age, gender, human constitution and body position. The heart's length in adults is 8.7-14.0 cm, the largest transverse heart size is 5-8 cm, front-facing - 6-8 cm on the surface of the heart are noticeable interventricular furrows: front and rear, covering the heart in front and rear, and transverse vernoy Grozda, Located ring-shaped. Along these furrows pass their own artery and veins of hearts. These furrows correspond to partitions separating the heart into 4 departments: longitudinal intercostal and interventricular partitions divide the organ into two isolated halves - right I. left heart; The transverse partition divides each of these half to the upper chamber - atrium and lower - ventricle.

The atrium take blood from the veins and pushed it into the ventricles, the blood of the artery thrown into the artery; Right - through the aorta, from which numerous arteries are departed to organs and body walls. Each atrium is reported to the corresponding ventricle and pozdarochekov Arteries. The right half of the heart contains venous blood, and the left is arterial.

Right atrium - It is a cavity volume., Reminds the form of a cube, is located at the bottom of the heart to the right and behind the aorta and the pulmonary trunk. It serves as a place to flow of hollow veins and the veins of the heart itself. The upper part is ushko atrium.

In the Wall of the Cardiac Muscle forms muscle protrusions located approximately in parallel, which are called great muscles. In the field of imposition of the lower hollow vein there is a not a large valve, which is its damper. On the inner wall of the right atrium is available oval yam (The fetal is a hole, through which from the right atrium, the blood passes into the left atrium, because the small circle of blood circulation has no fruit). Below and behind the edge of the oval fossa are the place of failure vernoe sinus, collecting most of the blood from the wall of the heart. The sion hole is closed by a valve sinus valve. The passage between the right atrium and the right ventricle is called the right atrocaded-ventricular hole. At the time of the systole of the right ventricle it closes right atrial and stomach (three-rolled) valve separating the cavity of the right ventricle from the right atrium and non-transmitting blood back to the right atrium. With a diastole ventricle, the valve opens towards the ventricle.

Right ventricle From the left ventricle, the interventricular partition is separated, most of which is muscular, and the smaller, located in the upper part, closer to the atria, is the webbed. Top in the wall of the ventricle two holes: Rear is the right atrocading and ventricular, and in front - the hole of the pulmonary trunk. The elongated funnel section of the ventricle in this place is called arterial cone. Directly above the hole of the pulmonary barrel consisting of the front, left and right semi-lunged dampers Located in a circle, convex surface into the cavity of the right ventricle, and concave and free edge - into the lumen of the pulmonary trunk. In the free edge, each of the dampers has a thickening - a nodule that helps a more dense closure of the semi-lone dampers when closing them. With the reduction of the muscles of the ventricle, the semi-lunutaneous dampers are pressed against the wall of the pulmonary trunk and do not interfere with the passage of blood from the ventricle; When relaxing, when the pressure in the ventricle cavity decreases, the return flow of blood fills the pockets between the wall of the pulmonary trunk and each of the semi-lone dampers and closes (reveals) the flaps, their edges are closed and do not let the blood to the heart.

The right atrial stomach hole is closed right preservative valve, Having anterior, rear and medial flaps. The latter fill triangular tendon plates. On the inner surface of the right ventricle, fleshy trabecules and cones are visible nipple muscles, from which to the edges and surfaces of the flaps go tendor chords. When reducing the attendsee of the valve sash presses the blood current to the stamps of the ventricle and do not interfere with its passage into the cavity of the latter. When cutting the muscles of the ventricle, the free edges of the sash are closed and held in such a position of tendon chords and a reduction in nobble muscles, not passing blood back in atrium.

Left atrium limited to the right intersdoch partition; It has left ear. In the backyard of the upper wall, 4 pulmonary veins are opened, devoid of valves, according to which arterial blood flows. With left ventricle is reported through the left atrial and ventricular hole.

Left ventricle In the front top department there is hole aorta. At the place of way out aortic from the left ventricle is located aortic valve, right, left and rear silver dampers. In the atrial and ventricular hole is left preservative Valve - (two-rolled mitral). Consisting of anterior and rear triangular flaps. On the inner surface of the left ventricle there is fleshy trabecules and 2-puzzle muscles, from which thick tendon chords are going attached to the mitral valve skeins.

The wall of the heart consists of three layers. Inner is called endocard middle - myocardium outdoor epicard.

Endocard - Woven all the cavities of the heart, faded with a muscular layer. From the side of the heart cavities, he is lined with endothelium. The endocardia forms the preservative valves, as well as the aortic valves and the pulmonary trunk.

Myocardia - It is the largest and powerful part of the heart wall functionality. It is formed by a cardiac cross-striped muscle tissue and consists of hearty myocytes (cardiomyocytes) interconnected by a large number of jumpers (inserted disks) with which they are associated with muscle complexes or fibers that form a narrow-scale network. It provides a complete rhythmic reduction in atria and ventricles.

The muscular layer of the walls of the atria is thin due to not a large load and consists of them superficial layer General for both atrium, and deep, separate for each of them. In the walls of the ventricles, it is the most significant in thickness, it is allocated in it. outer longitudinal, middle Ring I. interior longitudinal layer. Outdoor fibers in the field of heart tops are transferred to internal longitudinal fibers, and between them there are circular muscle fibers of the middle layer. The muscular layer of the left ventricle is the thickest.

Muscular fibers of the atrial and ventricles begin with fibrous rings located around the right and left atrocaded-ventricular holes, fully separating the myocardium atrium from the myocardium of ventricles.

Fibrous rings They form a kind of skeleton of the heart, which also includes thin coupling rings around the holes of the aorta and the pulmonary trunk and the right and left fibrous triangles adjacent to them.

The composition of the cardiac cross-striped muscular tissue includes typical contractile muscle cells - cardiomyocytes and atypical hearty myocytes forming the so-called so-called conductive system - consisting of nodes and beams that ensures the automatism of heart abbreviations, as well as coordinating the contractile function of the myocardium atrial and ventricles of the heart. The centers of the conductive system of the heart are 2 nodes: 1) sinuo-forever Knot (Kisa-Flex zode), it is called the driver of the heart rhythm. Located in the wall of the right atrium between the opening of the upper hollow vein and the right ear and the giving branch to the myocardium atrial.

2) preservative knot (Ashoffa-Tavara knot) is located in a partition between the atrium and ventricles. From this node leaves preservative bunch (Bunch of His), connecting the myocardium atrial sservs with the myocardium of the ventricles. In the interventricular partition, this bundle is divided into the right and left legs to the myocardium of the right and left ventricles. Heart gets innervation from wandering and sympathetic nerves.

IN last years The myocardium of the right atrium describes endocrine cardiomyocytes, secreting row of hormones (cardiopathrapine, cardiodilatin), which regulate the blood supply to the heart muscle.

Epicard is part of the fibrous serous shell pericardium Covering heart. In the pericarde, 2 layers are distinguished: fibrous pericardium formed by dense fibrous connective tissue, and serous pericardium, also consisting of fiber fabric with elastic fibers. It grows tightly to myocardium. In the region of the head of the heart, in which its blood vessels pass, under the epicardium, it is often possible from the surrounding organs, and the serous fluid between its plates reduces friction during heart abbreviations.

Blood supply Hearts occurs through the crown arteries, which are branches (right and left) of the emerging part of the aorta, departing from it at the level of its valves. The right branch goes not only to the right, but also the stop, dropping on the back of the interventricular head of the heart, left - left and kleondi, on the front interventricular furrow. Most of The heart of the heart is going to the bemark sinus, which flows into the right atrium and located in the Vernoy Broker. In addition, the individual small veins of the heart itself fall directly into the right atrium.

The pulmonary trunk at the place of his exit from the right ventricle is located in front of the aorta. There is an arterial bunch between the pulmonary artery and the lower surface of the aorta arc, which is the overgrown arterial duct (Botalles) functioning during the intrauterine period of life.

1 Cardiac layers

2 Delete into the outer layer

3 Why the heart of the bag?

4 When "sick" Pericard

5 injection in heart or pericardial puncture

Heart - How does it work?

Some facts about the work of the heart

Heart cameras

Valve apparatus

Layers of a heart wall

Some of the information about the hydrodynamics of the heart

Heart Reduction Phase

How does the heart bustling?

What does the heart work?

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Structure of the walls of the heart

Structure of the wall of the heart

Structure of the walls of the heart

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Structure of the wall of the heart.

Structure of the walls of the heart

133. Heart wall layers, their functions.

134. The degree of severity of the muscular layer in the heart chambers.

135. Features of the structure of the myocardium of ventricles and atrium.

136. Big and small circles circulation, their functions.

137. Heart valves, their functions.

Structure of the walls of the heart

Heart shell Anatomy

A heart. Endocard. Myocardium. Heart structure.

Heart shell

Outer sheath of the heart. Epicard

Muscular Heart Shell, or Myocardium

Inner heart sheath, or endocard

Okolosraid bag, or pericardium

Structure of the wall of the heart

Outer sheath of heart

Muscular heart sheath

Muscle sheath atserval

Muscle sheath of stomachs

Intestines

Parameters of different departments of the digestive tube

Duodenum (duodenum)

Skinny (Jejunum) and iliac (Ileum)

Blind intestine (Caecum)

The structure and functions of the small intestine

The structure of the organ

Digestion process

Functions of the small intestine

The structure of the thin and large intestines for dummies

Small intestine

Colon

1 Cardiac layers

2 Delete into the outer layer

3 Why the heart of the bag?

4 When "sick" Pericard

5 injection in heart or pericardial puncture

Structure of the wall of the heart.

Structure of the walls of the heart

The middle layer of the heart wall is formed from

Answers and explanations

133. Heart wall layers, their functions.

134. The degree of severity of the muscular layer in the heart chambers.

135. Features of the structure of the myocardium of ventricles and atrium.

136. Big and small circles circulation, their functions.

137. Heart valves, their functions.

Structure of the wall of the heart

Structure of the wall of the heart

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