The circulation is collateral. Collateral circulation in case of damage and ligation of the main arteries

Collateral Circulation

The role and types of collateral circulation

The term collateral circulation implies the flow of blood through the lateral branches to the peripheral parts of the limbs after the lumen of the main (main) trunk is blocked.

Collateral blood flow is an important functional mechanism of the body, due to the flexibility of blood vessels and is responsible for uninterrupted blood supply to tissues and organs, helping to survive myocardial infarction.

The role of collateral circulation

In fact, collateral circulation is a roundabout lateral blood flow, which is carried out through the lateral vessels. Under physiological conditions, it occurs when normal blood flow is difficult, or in pathological conditions - injuries, blockage, ligation of blood vessels during surgery.

The largest ones, which take on the role of a switched off artery immediately after blockage, are called anatomical or previous collaterals.

Groups and types

Depending on the localization of intervascular anastomoses, the previous collaterals are divided into the following groups:

Intrasystemic - short paths of roundabout blood circulation, that is, collaterals that connect the vessels of the pool of large arteries.
Intersystem - roundabout or long paths that connect pools of different vessels with each other.

Collateral circulation is divided into types:

Intraorganic connections - intervascular connections within a separate organ, between the vessels of the muscles and the walls of hollow organs.
Extraorgan connections - connections between the branches of the arteries that feed one or another organ or part of the body, as well as between large veins.

The following factors influence the strength of the collateral blood supply: the angle of origin from the main trunk; diameter of arterial branches; functional state of the vessels; anatomical features of the lateral antecedent branch; the number of lateral branches and the type of their branching. An important point for volumetric blood flow is the state of the collaterals: relaxed or spasmodic. The functional potential of collaterals determines regional peripheral resistance and general regional hemodynamics.

Anatomical development of collaterals

Collaterals can exist both under normal conditions and re-develop during the formation of anastomoses. Thus, a disruption of the normal blood supply caused by some obstruction to the blood flow in a vessel turns on already existing circulatory bypasses, and then new collaterals begin to develop. This leads to the fact that the blood successfully bypasses the areas in which the vascular patency is impaired and the impaired blood circulation is restored.

Collaterals can be divided into the following groups:

sufficiently developed, which are characterized by a wide development, the diameter of their vessels is the same as the diameter of the main artery. Even the complete blockage of the main artery has little effect on the blood circulation of such an area, since the anastomoses fully replace the decrease in blood flow;
insufficiently developed ones are located in organs where intraorgan arteries interact little with each other. They are usually called ring. The diameter of their vessels is much smaller than the diameter of the main artery.
relatively developed ones partially compensate for impaired blood circulation in the ischemic area.

Diagnostics

To diagnose collateral circulation, first of all, you need to take into account the speed of metabolic processes in the limbs. Knowing this indicator and competently influencing it with the help of physical, pharmacological and surgical methods, it is possible to maintain the viability of an organ or limb and stimulate the development of newly formed blood flow pathways. To do this, it is necessary to reduce the consumption of oxygen and nutrients by the tissues from the blood, or to activate collateral circulation.

What is collateral circulation

What is collateral circulation? Why do many doctors and professors focus on the important practical significance of this type of blood flow? Blockage of the veins can lead to a complete blockage of the movement of blood through the vessels, so the body begins to actively look for the possibility of supplying liquid tissue through lateral routes. This process is called collateral circulation.

The physiological characteristics of the body make it possible to supply blood through the vessels, which are located parallel to the main ones. Such systems have a name in medicine - collaterals, which is translated from Greek as "roundabout". This function allows for any pathological changes, injuries, surgical interventions to ensure uninterrupted blood supply to all organs and tissues.

Types of collateral circulation

In the human body, collateral circulation can have 3 types:

Absolute, or sufficient. In this case, the amount of collaterals that will slowly open is equal to or close to the main arteries of the main vessel. Such lateral vessels perfectly replace pathologically altered ones. Absolute collateral circulation is well developed in the intestines, lungs and all muscle groups.
Relative, or insufficient. Such collaterals are located in the skin, stomach and intestines, and the bladder. They open more slowly than the lumen of a pathologically altered vessel.
Insufficient. Such collaterals are unable to completely replace the main vessel and enable the blood to fully function in the body. Insufficient collaterals are located in the brain and heart, spleen and kidneys.

As medical practice shows, the development of collateral circulation depends on several factors:

individual features of the structure of the vascular system;
the time during which the blockage of the main veins occurred;
patient's age.

It should be understood that the collateral circulation is better developed and replaces the main veins at a young age.

How is the replacement of the main vessel with a collateral assessed?

If the patient was diagnosed with serious changes in the main arteries and veins of the limb, then the doctor makes an assessment of the adequacy of the development of collateral circulation.

To give a correct and accurate assessment, the specialist considers:

metabolic processes and their intensity in the limb;
treatment options (surgery, medications, and exercise);
the possibility of full development of new-forming pathways for the full functioning of all organs and systems.

The location of the affected vessel is also important. It will be better to produce blood flow at an acute angle of discharge of the branches of the circulatory system. If you choose an obtuse angle, then the hemodynamics of the vessels will be difficult.

Numerous medical observations have shown that in order to fully open the collaterals, it is necessary to block the reflex spasm in the nerve endings. Such a process may appear, since when a ligature is applied to an artery, irritation of the nerve semantic fibers occurs. Spasms can block the full disclosure of the collateral, so such patients undergo a novocaine blockade of the sympathetic nodes.

Acute coronary syndrome is the acute phase of IHD. Atherosclerosis underlying CHD is not a linearly progressive, stable process. For atherosclerosis of the coronary arteries, a change in the phases of a stable course and exacerbation of the disease is characteristic.

IHD - mismatch of coronary blood flow to the metabolic needs of the myocardium, i.e. the volume of myocardial oxygen consumption (PMO2).

In some cases, the clinical picture of chronic stable coronary artery disease is due to symptoms and signs of LV dysfunction. This condition is referred to as ischemic cardiomyopathy. Ischemic cardiomyopathy is the most common form of heart failure in developed countries, reaching a level of 2/3 to 3/4 of cases of dil.

Collateral coronary circulation

Networks of small branches-anastomoses internally connect the main coronary arteries (CA) and serve as precursors of collateral circulation, which provides myocardial perfusion, despite severe proximal narrowing of the coronary arteries (CA) of atherosclerotic origin.

The collateral ducts may be invisible in patients with normal and mildly damaged coronary arteries (CA) due to their small (< 200 мкм) калибра, но по мере прогрессирования КБС и увеличения ее тяжести (>90% stenosis) in the ducts of the anastomosis occurs ▲P in relation to the distal hypoperfused areas.

Transstenotic ▲P promotes blood flow through the anastomotic vessels, which progressively dilate and eventually become visible as collateral vessels.

The visible collateral ducts arise either from the contralateral coronary artery or from the lateral coronary artery located on the same side, through the intracoronary collateral ducts, or through the bridging canals, which are serpentine from the proximal coronary artery to the coronary artery distal to the occlusion.

These collaterals can provide up to 50% of anterograde coronary blood flow in chronic total occlusion and may be involved in creating myocardially perfused "protective" areas that do not develop myocardial ischemia during times of increased oxygen demand. Involvement of collateral canals can quickly occur in patients who develop OHM ST as a result of unexpected occlusion by thrombosis.

Other factors that determine the development of collaterals include the condition of the arteries supplying the collaterals, the size and vascular resistance of the segment distal to the stenosis.

Collateral flow quality can be classified using Rentrop criteria, including grade 0 (no filling), grade 1 (small lateral branches filled), grade 2 (partial epicardial filling of the occluded coronary artery), or grade 3 (complete epicardial filling of the occluded coronary artery).

(A) A branch of Kygel's originates from the proximal right coronary artery and continues to the distal posterior descending branch of the right coronary artery (arrow).

(B) Bridging collaterals (arrow) linking the proximal and distal portions of the right coronary artery.

(B) "Microduct" in the left middle anterior descending artery (arrow).

(D) The Viessen collateral runs from the proximal right coronary artery to the left anterior descending artery (arrow).

Collateral coronary circulation

So what does the course of IHD depend on?

The main reason for the development and progression of coronary artery disease is the defeat of the coronary arteries of the heart by atherosclerosis. A decrease in the lumen of the coronary artery by 50% can already be clinically manifested by angina attacks. A decrease in the lumen by 75 percent or more gives the classic symptoms - the appearance of angina attacks during or after physical and emotional stress and a fairly high probability of developing myocardial infarction.

However, in the human body, as a biological object of a higher order, there is a huge reserve potential, which is included in any pathological process. In stenosing atherosclerosis of the coronary arteries, the main compensation mechanism is collateral circulation, which takes over the function of blood supply to the heart muscle in the basin of the affected artery.

What is collateral circulation?

The scientific assumption about the compensatory capabilities of the vascular system in coronary insufficiency has almost two hundred years of history. The first information about the presence of collaterals was obtained by A.Scarpa in 1813, but only the dissertation work of the Russian surgeon and researcher N.I. Pirogov laid the foundation for the doctrine of collateral circulation. However, a whole era has passed from the numerous pathoanatomical studies carried out to the modern understanding of the mechanism of development of collateral circulatory pathways.

The coronary bed, which ensures the viability of the myocardium, consists of the left and right coronary arteries. The basin of the left coronary artery is represented by the anterior interventricular, circumflex and diagonal arteries. When it comes to coronary atherosclerosis, in most cases the stenotic process develops here - in one or several arteries.

In addition to the large main arteries in the heart, there are vascular formations - coronary anastomoses that penetrate all layers of the myocardium and connect the arteries to each other. The diameter of the coronary anastomoses is small, from 40 to 1000 microns. In a healthy heart, they are in a "dormant" state, they are underdeveloped vessels and their functional significance is small. But it is not difficult to imagine what will happen to these vessels when the main blood flow encounters an obstacle on its usual route. As a child, everyone probably loved to watch the stream after the rain: it is worth blocking it with a stone or a sliver, as the water immediately begins to look for new passages, breaks them where it “feels” the slightest slope, bypasses the obstacle and returns to its native channel. It can be said that the dam forced the stream to seek its collaterals.

Of considerable importance in maintaining collateral circulation are intramural anastomoses: Tebesius vessels and sinusoidal spaces. They are located in the myocardium and open into the cavity of the heart. The role of the Thebsian vessels and sinusoidal spaces as sources of collateral circulation has recently been intensively studied in connection with the introduction of transmyocardial laser revascularization into clinical practice in patients with multiple lesions of the coronary bed.

There are non-cardiac anastomoses - anatomical connections of the arteries of the heart with the arteries of the pericardium, mediastinum, diaphragm, bronchial. For each person, they have their own unique structure, which explains the individual level of myocardial protection under various effects on the cardiovascular system.

Congenital failure of coronary anastomoses can cause myocardial ischemia without visible changes in the main coronary arteries. In addition to the anastomoses present in the heart from birth, collateral connections are distinguished, which are formed during the appearance and progression of coronary atherosclerosis. It is these newly formed arterial vessels that are true collaterals. The fate of a patient with coronary heart disease, the course and outcome of coronary artery disease often depend on the rate of their formation and functional viability.

Acute occlusion of the coronary arteries (cessation of blood flow due to thrombosis, complete stenosis or spasm) is accompanied by the appearance of collateral circulatory pathways in 80% of cases. With a slowly developing process of stenosis, roundabout ways of blood flow are detected in 100% of cases. But for the prognosis of the disease, the question of how effective these bypasses are is very important.

Hemodynamically significant are collaterals extending from intact coronary arteries, and in the presence of occlusion - developed above the stenotic area. However, in practice, the formation of collaterals above the stenotic site occurs only in 20-30% of patients with coronary artery disease. In other cases, roundabout ways of blood flow are formed at the level of the distal (final) branches of the coronary arteries. Thus, in most IHD patients, the ability of the myocardium to resist atherosclerotic lesions of the coronary arteries and compensate for physical and emotional stress is due to the adequacy of the distal blood supply. The collaterals that develop in the process of progression are sometimes so effective that a person endures quite large loads without assuming the presence of a lesion of the coronary arteries. This explains those cases when a myocardial infarction develops in a person without previous clinical symptoms of angina pectoris.

This brief and, perhaps, not very easy to understand review of the anatomical and functional features of the blood supply to the heart muscle - the main "pumping" organ that ensures the life of the body - is presented to the readers' attention not by chance. In order to actively resist coronary artery disease, the "number one" disease in the sad statistics of mortality, a certain medical awareness and absolute disposition of each person is necessary for a long struggle with such an insidious and strong adversary as atherosclerosis. In previous issues of the journal, the necessary methods for examining a potential patient with coronary artery disease were presented in detail. Nevertheless, it seems appropriate to recall that males over 40 years of age and women aged 45-50 years should show their interest and perseverance in conducting a cardiac examination.

The algorithm is simple, available if desired, and includes the following diagnostic methods:

study of lipid metabolism (determination of risk factors such as hypercholesterolemia and hypertriglyceridemia - they were discussed in ZiU No. 11 / 2000);
study of microcirculation, which allows a non-invasive method to identify early signs of damage to the cardiovascular system and indirectly assess the state of collaterals. (Read about this in ZiU No. 12/2000.)
determination of coronary reserve and detection of signs of myocardial ischemia during exercise. (Functional examination methods must necessarily include a bicycle ergometric test under ECG control)
echocardiographic examination (assessment of intracardiac hemodynamics, the presence of atherosclerotic lesions of the aorta and myocardium).

The results of such a diagnostic complex will allow, with a high degree of certainty, to identify coronary artery disease and outline tactics for further examination and timely treatment. If you already have, perhaps not quite “intelligible” symptoms in the form of pain, discomfort or discomfort with localization behind the sternum and irradiation to the neck, lower jaw, to the left arm, which can be associated with physical and emotional stress; if in your family the next of kin suffer from coronary artery disease or hereditary hypercholesterolemia, a cardiological examination in the specified volume should be carried out at any age.

Of course, the most reliable method for detecting lesions of the coronary bed is coronary angiography. It allows you to determine the degree and extent of atherosclerotic lesions of the arteries, assess the state of collateral circulation and, most importantly, outline the optimal treatment tactics. Indications for this diagnostic procedure are determined by the cardiologist in the presence of signs of coronary artery disease. This examination is not easily accessible for Belarusian residents; it is carried out only in a few specialized centers in Minsk and Gomel. To some extent, this explains the late coronary angiography, in connection with which, as a rule, patients with coronary artery disease with a “severe” class of angina pectoris, who often have a history of myocardial infarction, are referred for surgical myocardial revascularization in our country, while in Western countries Europe and the USA, coronary angiography is performed after the first "coronary attack" documented during bicycle ergometry. However, the possibility of coronary angiography in our country is available and, if indicated, it should be performed in a timely manner.

The arsenal of therapeutic effects and medical technologies in modern Belarusian cardiology is sufficient to provide adequate assistance to a patient with coronary artery disease. This is classical cardiac surgery - aortocorsor bypass operations both under cardiopulmonary bypass and on a "working" heart. This is a minimally invasive cardiac surgery - balloon dilatation (expansion) of the affected area of the coronary artery with the installation of a special device - a stent, to increase the effectiveness of the procedure. This is transmyocardial laser myocardial revascularization, which was mentioned above. These are drug treatment regimens using pentoxifylline (trental, agapurine) and non-drug technologies such as selective plasmapheresis and low-intensity infrared laser therapy. They are the technologies of choice in patients who, for a number of reasons, cannot undergo surgical correction of atherosclerotic lesions of the coronary bed.

Collateral circulation;

Ligation of arteries throughout can be used not only as a way to stop bleeding from a damaged vessel, but also as a method of preventing it before performing some complex operations. For the correct exposure of the artery for the purpose of ligation throughout, it is necessary to perform an operative access, which requires knowledge of the projection lines of the arteries. It should be especially emphasized that for drawing the projection line of the artery, it is preferable to use the most easily defined and non-displaceable bone protrusions as a guide. The use of soft tissue contours can lead to an error, since with edema, development of a hematoma, aneurysm, the shape of the limb, the position of the muscles may change and the projection line will be incorrect. To expose the artery, an incision is made strictly along the projection line, dissecting the tissues in layers. Such access is called direct access. Its use allows you to approach the artery in the shortest way, reducing surgical trauma and operation time. However, in some cases, the use of direct access can lead to complications. To avoid complications, an incision to expose the arteries is made somewhat away from the projection line. Such access is called roundabout. The use of a roundabout approach complicates the operation, but at the same time avoids possible complications. Operative method of stopping bleeding by ligating the artery throughout excludes the isolation of the artery from the sheath of the neurovascular bundle, and its ligation. To avoid damage to the elements of the neurovascular bundle, novocaine is first introduced into its vagina for the purpose of "hydraulic preparation", and the vagina is opened using a grooved probe. Before ligation, the artery is carefully isolated from the surrounding connective tissue.

However, ligation of large main arteries not only stops bleeding, but also dramatically reduces blood flow to the peripheral parts of the limb, sometimes the viability and function of the peripheral part of the limb is not significantly impaired, but more often due to ischemia, necrosis (gangrene) of the distal part of the limb develops. In this case, the frequency of gangrene development depends on the level of arterial ligation and anatomical conditions, the development of collateral circulation.

The term collateral circulation is understood as the flow of blood into the peripheral parts of the limb along the lateral branches and their anastomoses after the lumen of the main (main) trunk is closed. The largest ones, which take over the function of the switched off artery immediately after ligation or blockage, are referred to as the so-called anatomical or pre-existing collaterals. Pre-existing collaterals can be divided into several groups according to the location of intervascular anastomoses: collaterals connecting the vessels of a basin of a large artery are called intrasystemic, or short paths of roundabout blood circulation. Collaterals connecting pools of different vessels with each other (external and internal carotid arteries, the brachial artery with the arteries of the forearm, the femoral artery with the arteries of the lower leg) are referred to as intersystemic, or long, roundabout ways. Intraorganic connections include connections between vessels within an organ (between the arteries of adjacent lobes of the liver). Extraorganic (between the branches of the own hepatic artery in the gates of the liver, including with the arteries of the stomach). Anatomical pre-existing collaterals after ligation (or blockage by a thrombus) of the main arterial trunk take on the function of conducting blood to the peripheral parts of the limb (region, organ). At the same time, depending on the anatomical development and functional sufficiency of the collaterals, three possibilities are created for restoring blood circulation: the anastomoses are wide enough to fully provide blood supply to the tissues, despite the shutdown of the main artery; anastomoses are poorly developed, roundabout blood circulation does not provide nutrition to the peripheral sections, ischemia occurs, and then necrosis; there are anastomoses, but the volume of blood flowing through them to the periphery is small for a full blood supply, and therefore newly formed collaterals are of particular importance. The intensity of the collateral circulation depends on a number of factors: on the anatomical features of the preexisting lateral branches, the diameter of the arterial branches, the angle of their departure from the main trunk, the number of lateral branches and the type of branching, as well as on the functional state of the vessels (on the tone of their walls). For volumetric blood flow, it is very important whether the collaterals are in a spasmodic or, conversely, in a relaxed state. It is the functionality of collaterals that determines regional hemodynamics in general and the magnitude of regional peripheral resistance in particular.

To assess the sufficiency of collateral circulation, it is necessary to keep in mind the intensity of metabolic processes in the limb. Considering these factors and influencing them with the help of surgical, pharmacological and physical methods, it is possible to maintain the viability of a limb or any organ in case of functional insufficiency of pre-existing collaterals and promote the development of newly formed blood flow pathways. This can be achieved either by activating collateral circulation or by reducing tissue uptake of blood-borne nutrients and oxygen. First of all, the anatomical features of the pre-existing collaterals must be taken into account when choosing the site for applying the ligature. It is necessary to spare as much as possible the existing large lateral branches and apply a ligature as far as possible below the level of their departure from the main trunk. Of certain importance for collateral blood flow is the angle of departure of the lateral branches from the main trunk. The best conditions for blood flow are created with an acute angle of origin of the lateral branches, while an obtuse angle of origin of the lateral vessels complicates hemodynamics due to an increase in hemodynamic resistance. When considering the anatomical features of pre-existing collaterals, it is necessary to take into account the varying degrees of anastomoses and the conditions for the development of newly formed blood flow pathways. Naturally, in those areas where there are many vascular-rich muscles, there are also the most favorable conditions for collateral blood flow and neoplasms of collaterals. It must be taken into account that when a ligature is applied to an artery, irritation of sympathetic nerve fibers, which are vasoconstrictors, occurs, and a reflex spasm of collaterals occurs, and the arteriolar link of the vascular bed is switched off from the bloodstream. Sympathetic nerve fibers run in the outer sheath of the arteries. To eliminate the reflex spasm of the collaterals and maximize the opening of the arterioles, one of the ways is to cross the artery wall along with sympathetic nerve fibers between two ligatures. Periarterial sympathectomy is also recommended. A similar effect can be achieved by introducing novocaine into the periarterial tissue or novocaine blockade of sympathetic nodes.

In addition, when the artery is crossed, due to the divergence of its ends, the direct and obtuse angles of the lateral branches are changed to an acute angle more favorable for blood flow, which reduces hemodynamic resistance and improves collateral circulation.

Collateral circulation

Collateral circulation refers to the lateral circulation of blood through the lateral vessels. It occurs under physiological conditions with temporary difficulties in blood flow (for example, when the vessels are compressed in places of movement, in the joints). It can also occur in pathological conditions - with blockage, injuries, ligation of blood vessels during operations, etc.

Under physiological conditions, the roundabout blood flow is carried out along the lateral anastomoses, which run parallel to the main ones. These lateral vessels are called collaterals (for example, a. collateralis ulnaris, etc.), hence the name of the blood flow - roundabout, or collateral circulation.

If the blood flow through the main vessels is difficult due to their blockage, damage or ligation during operations, the blood rushes along the anastomoses to the nearest lateral vessels, which expand and become tortuous, the vascular wall is rebuilt due to changes in the muscular membrane and the elastic framework, and they are gradually transformed into collaterals different structure than normal.

Thus, collaterals exist under normal conditions, and can develop again in the presence of anastomoses. Therefore, in case of a disorder in the normal circulation caused by an obstruction in the path of blood flow in a given vessel, the existing bypass blood tracts, collaterals, are first switched on, and then new ones develop. As a result, impaired blood circulation is restored. The nervous system plays an important role in this process.

From the foregoing, it is necessary to clearly define the difference between anastomoses and collaterals.

Anastomosis (anastomoo, Greek - I supply the mouth) - fistula - this is any third vessel that connects the other two - an anatomical concept.

Collateral (collateralis, lat. - lateral) is a lateral vessel that carries out a roundabout blood flow; concept - anatomical and physiological.

Collaterals are of two kinds. Some exist normally and have the structure of a normal vessel, like anastomosis. Others develop again from anastomoses and acquire a special structure.

To understand the collateral circulation, it is necessary to know those anastomoses that connect the systems of various vessels, through which the collateral blood flow is established in case of vessel injuries, ligation during operations and blockage (thrombosis and embolism).

Anastomoses between the branches of large arterial highways supplying the main parts of the body (aorta, carotid arteries, subclavian, iliac, etc.) and representing, as it were, separate vascular systems, are called intersystemic. Anastomoses between the branches of one large arterial highway, limited to the limits of its branching, are called intrasystemic.

These anastomoses have already been noted in the course of presentation of the arteries.

There are anastomoses between the finest intraorgan arteries and veins - arteriovenous anastomoses. Through them, blood flows bypassing the microvasculature when it overflows and, thus, forms a collateral path that directly connects the arteries and veins, bypassing the capillaries.

In addition, thin arteries and veins that accompany the main vessels in the neurovascular bundles and make up the so-called perivascular and perinervous arterial and venous bed take part in the collateral circulation.

Anastomoses, in addition to their practical significance, are an expression of the unity of the arterial system, which, for the convenience of study, we artificially divide into separate parts.

Collateral circulation

The term collateral circulation refers to

blood flow to the peripheral parts of the limb along the

kovy branches and their anastomoses after closing the lumen of the main

leg (main) trunk. The largest hosts

take over the function of the disabled artery immediately after ligation

or blockages, refer to the so-called anatomical or

preexisting collaterals. Pre-existing collates

localization of intervascular anastomoses can be divided

pour into several groups: collaterals connecting between

fight the vessels of the basin of any large artery, called

intrasystemic, or short circuits of roundabout blood circulation

scheniya. The collaterals connecting the basins of the

vessels (external and internal carotid arteries, brachial

arteries with the arteries of the forearm, femoral with the arteries of the lower leg),

are referred to as intersystem, or long, detours. To the inside

riorgan connections include connections between vessels

inside the organ (between the arteries of adjacent lobes of the liver). Vneor-

gannye (between the branches of the own hepatic artery in the portal

of the liver, including those with the arteries of the stomach). Anatomical

pre-existing collaterals after ligation (or blockage)

thrombus) of the main main arterial trunk with

take on the function of conducting blood to the peripheral

affairs of a limb (region, organ). However, depending on

anatomical development and functional sufficiency

laterals, three possibilities are created for restoring blood

treatment: the anastomoses are wide enough to completely

ensure blood supply to tissues, despite the shutdown of the ma-

gistral artery; anastomoses are poorly developed, roundabout blood

treatment does not provide nutrition to peripheral departments,

ischemia occurs, and then necrosis; there are anastomoses, but the volume

blood flowing through them to the periphery is small for a full

blood supply, in connection with which they are of particular importance

newly formed collaterals. The intensity of the collateral

blood circulation depends on a number of factors: on the anatomical

features of pre-existing lateral branches, diameter

arterial branches, the angle of their departure from the main trunk,

the number of lateral branches and the type of branching, as well as on the functional

the state of the vessels, (from the tone of their walls). For volumetric

th blood flow, it is very important whether the collaterals are in spasm

bath or, conversely, in a relaxed state. Exactly

functionality of collaterals determines the region

overall hemodynamics and the magnitude of the regional peri-

ferric resistance in particular.

To assess the sufficiency of collateral circulation

it is necessary to keep in mind the intensity of metabolic processes

in the limb. Considering these factors and influencing them

through surgical, pharmacological and physical

ways to maintain limb viability

or any organ with functional insufficiency

pre-existing collaterals and promote the development of new

emerging pathways of blood flow. This can be achieved either by

activating collateral circulation, or reducing

tissue uptake of blood-borne nutrients

and oxygen. First of all, the anatomical features pre-

existing collaterals must be considered when choosing

ligature sites. It is necessary to spare as much as possible

growing large lateral branches and apply a ligature according to

below the level of their departure from the main shaft.

Of particular importance for collateral blood flow is

angle of branching of lateral branches from the main trunk. Best

conditions for blood flow are created with an acute angle of discharge

lateral branches, while the obtuse angle of origin of the lateral

blood vessels complicates hemodynamics, due to an increase in hemo-

dynamic resistance. When considering anatomical

features of preexisting collaterals must be taken into account

varying degrees of severity of anastomoses and conditions

for the development of newly formed pathways of blood flow. Naturally,

that in those areas where there are many vascular-rich muscles, there are

and the most favorable conditions for collateral bleeding

ka and neoplasms of collaterals. It must be taken into account that

when applying a ligature to an artery, irritation occurs

sympathetic nerve fibers, which are vasoconstrictors

mi, and there is a reflex spasm of collaterals, and from

blood flow, the arteriolar link of the vascular bed is switched off.

Sympathetic nerve fibers run in the outer sheath

arteries. To eliminate reflex spasm of collaterals

and maximum disclosure of arterioles, one of the ways is

Xia intersection of the wall of the artery together with sympathetic nerves

management of periarterial sympathectomy. similar

effect can be achieved by introducing novocaine into the periarterial

ny fiber or novocaine blockade of sympathetic nodes.

In addition, when crossing an artery due to divergence

its ends there is a change in the direct and obtuse angles of the outgoing

derivation of the lateral branches to a more favorable stop for blood flow

ry angle, which reduces hemodynamic resistance and

contributes to the improvement of collateral circulation.

Table of contents of the topic "Patterns of the distribution of arteries.":

Collateral circulation there is an important functional adaptation of the body, associated with the great plasticity of blood vessels and ensuring uninterrupted blood supply to organs and tissues. Its deep study, which is of great practical importance, is associated with the name of V. N. Tonkov and his school

Collateral circulation refers to lateral, roundabout blood flow, carried out through the lateral vessels. It occurs under physiological conditions with temporary difficulties in blood flow (for example, when the vessels are compressed in places of movement, in the joints). It can also occur in pathological conditions with blockage, wounds, ligation of blood vessels during operations, etc.

If the blood flow through the main vessels is obstructed due to their blockage, damage or ligation during operations, the blood rushes through the anastomoses to the nearest lateral vessels, which expand and become tortuous, their vascular wall is rebuilt due to changes in the muscular membrane and the elastic skeleton, and they are gradually transformed into collaterals different structure than normal.

Thus, collaterals exist under normal conditions, and can develop again with anastomoses. Consequently, in case of a disorder in the normal circulation caused by an obstruction in the path of blood flow in a given vessel, the existing bypass blood paths - collaterals - are first switched on, and then new ones develop. As a result, impaired blood circulation is restored. The nervous system plays an important role in this process.

From the foregoing, it is necessary to clearly define difference between anastomoses and collaterals.

Anastomosis (from the Greek anastomos - I supply the mouth)- fistula, any third vessel that connects the other two; This is an anatomical concept.

Collateral (from lat. collateralis - lateral)- a lateral vessel that carries out a roundabout blood flow; the concept is anatomical and physiological.

Collaterals are of two kinds. Some exist normally and have the structure of a normal vessel, like anastomosis. Others develop again from anastomoses and acquire a special structure.

To understand collateral circulation it is necessary to know those anastomoses that connect the systems of various vessels, through which collateral blood flow is established in case of vascular injuries, ligation during operations and blockage (thrombosis and embolism).

Anastomoses between branches of large arterial highways, supplying the main parts of the body (aorta, carotid arteries, subclavian, iliac, etc.) and representing, as it were, separate vascular systems, are called intersystemic. Anastomoses between the branches of one large arterial highway, limited to the limits of its branching, are called intrasystemic. These anastomoses have already been noted in the course of presentation of the arteries.

There are anastomoses between the thinnest intraorgan arteries and veins - arteriovenous anastomoses. Through them, blood flows around the microcirculatory bed when it overflows and, thus, forms a collateral path that directly connects the arteries and veins, bypassing the capillaries.

Anastomosis, in addition to their practical significance, they are an expression of the unity of the arterial system, which, for the convenience of study, we artificially divide into separate parts.

Intraorganic connections refer to connections between vessels within an organ. Extraorganic (between the branches of the own hepatic artery in the gates of the liver, including with the arteries of the stomach). Anatomical pre-existing collaterals after ligation (or blockage by a thrombus) of the main arterial trunk take on the function of conducting blood to the peripheral parts of the limb (region, organ). The intensity of collateral circulation depends on a number of factors: on the anatomical features of the pre-existing lateral branches, the diameter of the arterial branches, the angle of their departure from the main trunk, the number of lateral branches and the type of branching, as well as on the functional state of the vessels (on the tone of their walls). For volumetric blood flow, it is very important whether the collaterals are in a spasmodic or, conversely, in a relaxed state. It is the functionality of collaterals that determines regional hemodynamics in general and the magnitude of regional peripheral resistance in particular.

First of all, the anatomical features of the pre-existing collaterals must be taken into account when choosing the site for applying the ligature. It is necessary to spare as much as possible the existing large lateral branches and apply a ligature as far as possible below the level of their departure from the main trunk. Of certain importance for collateral blood flow is the angle of departure of the lateral branches from the main trunk. The best conditions for blood flow are created with an acute angle of origin of the lateral branches, while an obtuse angle of origin of the lateral vessels complicates hemodynamics due to an increase in hemodynamic resistance.

Vascular drugs to improve blood circulation are prescribed by a doctor after establishing the cause of the pathological condition. In case of violation of the work of blood vessels, the brain will first suffer, then the arms, legs and the whole body. This is due to the fact that they are quite far from the heart. They can also receive great physical exertion. As a result, diseases arise that require complex treatment. In this situation, you can not do without special effective drugs.

Causes of poor blood flow

The main reasons for the deterioration of blood circulation in the vessels can be:

A disease called atherosclerosis. In this case, a large amount of cholesterol accumulates. The cavity of the vessels from this becomes narrow.
Heavy smokers are at risk. Nicotine settles on the walls of blood vessels and provokes their blockage. Quite often in this case, the appearance of varicose veins occurs.

A similar situation is observed in overweight people who eat a lot of fatty foods. This becomes especially dangerous after 45 years. Metabolism slows down, and fat fills the free cavity of blood vessels.
People who are characterized by a life without sports and physical education, sedentary work. These factors contribute to the deterioration of blood circulation and the development of complex diseases.
Diseases that require serious treatment also contribute to the deterioration of blood circulation. It can be diabetes, overweight, heart disease, hypertension, poor kidney function, spinal diseases.
Indiscriminate and prolonged use of drugs.

In such cases, diseases of the vessels of the arms and legs develop. There is a malfunction of the brain. The patient begins to feel a deterioration in the general state of health, the usual rhythm of life is disturbed.

In order for the doctor to choose a method of treatment and prescribe effective drugs, you need to find out the cause of a person’s illness. For this, a patient examination and laboratory testing, if necessary, is carried out.

Special preparations

The drug to improve blood circulation is prescribed only by a doctor. Prescribed medications can be used externally or internally. In the first case, their action will be aimed at relieving swelling, inflammation and stopping spasm. "Internal" drugs affect the entire vascular system. Therefore, it can be not only tablets. Normalization will take place gradually.

What will improve blood circulation:

Antispasmodics. They are effective in the appearance of spasms, able to relieve pain. If atherosclerosis is detected, it is useless to use antispasmodics. Often the doctor prescribes Cavinton, Galidor, Eufillin.
Angioprotectors. This group of drugs improves the condition of the vessels themselves. They will become elastic and normally permeable. There is an improvement in metabolism. Such drugs include Curantil, Vasonite, Doxy-Hem, Flexital.
Preparations from natural ingredients. In this case, we mean physiotherapy, which will be combined with other drugs. For example, Tanakan, Bilobil can be used.

A group of drugs based on prostaglandin E1. These medicines have properties that will help normalize blood circulation, reduce blood density, and expand the vessels themselves. It can be Vasaprostan, which normalizes blood flow.
Medicines based on low molecular weight dextran. These drugs will contribute to a better release of blood from the tissue and significantly improve its movement. Then choose Reomacrodex or Reopoliglyukin.
Calcium channel blockers. If necessary, to influence the work of the entire vascular system, drugs such as Stamlo, Kordafen, Plendil, Norvask are chosen. In this case, the impact will occur on the vessels of the arms and legs, of course, on the central nervous system.

Medicines for circulatory disorders of the brain

Preparations for blood circulation and its improvement can be divided into several groups.

Means to improve blood flow should have the following qualities:

the ability to expand blood vessels;
the ability to improve the flow of oxygen into the blood;
the ability to make the blood not so thick;
the ability to eliminate the problem in the cervical spine, if any.

Medicines that can improve blood circulation in the brain. At the same time, they should expand the vessels, make the blood not so viscous. To do this, use Cavinton, Vinpocetine.
Necessary use of drugs having antioxidant properties. They will help get rid of excess fat without violating the integrity of the cells. In this case, vitamin E, Mexidol is suitable.
Nootropics. They will restore the work of the brain, improve memory. They increase the protective functions of nerve cells, normalize their work. In this case, Piracetam, Ceraxon, Citicoline, Phezam are prescribed.
In pharmacology, such a group of drugs is distinguished - venotonics. They are able to improve blood flow and restore microcirculation. The drugs of this group have a capillary-protective effect. It can be Diosmin, Detralex, Phlebodia.
If there is a threat of swelling of the brain, diuretics may be prescribed. Circulation-improving drugs Furosemide, Mannitol.
Drugs that are analogues of the histamine mediator. They improve the functioning of the vestibular apparatus, relieve the patient of dizziness. These include Betaserc, Vestibo, Betahistine.
Taking vitamins is a must. Neurobeks, Cytoflavin, Milgamma are ideal.
Drugs that will help restore the cervical joints. You can use Chondroitin, Artron, Teraflex.

These are quite effective remedies, but it must be remembered that only after examination and examination can the doctor make appointments. This applies to all diseases.

Features of atherosclerosis MAG (main arteries of the head)

According to the latest sad statistics, more and more people are being diagnosed with atherosclerosis. If earlier this disease was considered age-related, now it is rapidly getting younger. Its most dangerous variety is stenosing atherosclerosis of the MAG (main arteries of the head). The problem is associated with the deposition of cholesterol plaques in the blood vessels of the brain, neck and large arteries of the lower extremities. The disease is chronic and it is impossible to completely get rid of it. But measures can be taken to stop its rapid development. To do this, you need to remember the peculiarity of the course of the disease and the main therapeutic methods.

Features of atherosclerosis of the main vessels

The development of atherosclerosis is associated with the deposition of fat cells on the walls of the arteries. At the beginning, the clusters are small and do not cause serious harm. If measures are not taken in time, then the plaques grow significantly and block the lumen of the vessels. As a result, blood circulation deteriorates.

Atherosclerosis of the main arteries of the head is a serious danger to humans. As the disease progresses, there is a blockage of the vessels of the neck and head, which are responsible for the full blood supply to the brain.

A severe form of the disease may be accompanied by the destruction of the vessel wall and the formation of an aneurysm. Thromboembolism can aggravate the situation. The rupture of such an aneurysm is fraught with serious health consequences, including death.

Depending on the severity of the disease, there are two main varieties:

non-stenosing atherosclerosis. This term refers to a condition in which the plaque covers no more than 50% of the lumen of the vessel. This form is considered the least dangerous to human life and health.
stenosing atherosclerosis. With this course of the disease, the vessel is blocked by a plaque by more than half. This greatly impairs the blood supply to the internal organs.

The sooner the disease is diagnosed, the greater the chance of successful treatment. It is almost impossible to completely get rid of the disease, so each person needs to take measures to eliminate the factors that provoke atherosclerosis.

What factors cause the onset of the disease?

In order for the treatment of atherosclerosis of MAH to be successful, it is necessary to identify and eliminate the cause of its occurrence. Among them are:

Increased blood pressure.
An excess of cholesterol in the blood.
Diseases of the endocrine system.
Excessive drinking and smoking.
Problems with the absorption of glucose.
Lack of physical activity.
Adherence to malnutrition.
Age-related changes in the body.
Prolonged exposure to stressful situations.
Overweight.

Most often, the disease affects older men. It is especially important for them to control the state of their health, adhere to the correct principles of competent nutrition and lifestyle.

Each person periodically needs to control the level of blood pressure and cholesterol in the blood. A timely medical examination will help in this.

Symptoms of atherosclerosis

Atherosclerosis of extracranial arteries is manifested by vivid symptoms. It will largely depend on the localization of plaques. If the lesion occurs in the vessels of the brain, then the following symptoms appear:

The appearance of noise in the ears.
Intense headaches and dizziness.
Memory problems.
Discoordination of movements, impaired speech. Other neurological abnormalities may also be present.
Sleep problems. A person falls asleep for a long time, often wakes up in the middle of the night, during the day he is tormented by drowsiness.
Change in the psyche. There is increased irritability, anxiety of a person, he becomes whiny and suspicious.

Atherosclerotic lesions can also be localized in the arteries of the extremities. In this case, the symptoms will be different. The following signs of the disease appear:

Decreased pulsation in the lower extremities.
Rapid fatigue during physical exertion. This is especially pronounced when walking long distances.
Hands become cold. Small sores may appear on them.
In severe cases, gangrene develops.
If the vessels of the lower extremities are affected, then the person begins to limp.
The nail plates become thinner.
There is hair loss on the lower extremities.

Symptoms of atherosclerosis MAH can have varying degrees of severity. At the initial stage, it is possible to identify the problem only during a medical examination.

If you find the first signs of the disease, you should immediately consult a doctor. Only under the condition of a timely diagnosis will it be possible to stop the development of the disease.

Making an accurate diagnosis

It is possible to identify the defeat of the main arteries of the head only during a full medical examination. Specialists need to determine the localization of the problem, the parameters of the formed plaque, as well as the presence of proliferation of connective tissue.

The following diagnostic methods are used:

General and biochemical blood tests.
Ultrasound procedure. An examination of the vascular system, which is responsible for the blood supply to the brain, is carried out. The carotid and vertebral arteries are examined. The specialist determines their condition, diameter, change in lumen.
Magnetic resonance imaging. This is a survey that allows you to study in great detail the structure of the arteries of the brain, neck, limbs. Modern equipment guarantees taking pictures in various projections. This technique is considered the most informative.
Angiography. Allows you to study all the pathologies of the vascular system. A specialized contrast agent is injected into the patient's blood. This is followed by an X-ray examination.

The specific method of examination is chosen by the doctor individually for each patient. This takes into account the characteristics of the body, as well as the equipment that the medical institution has.

How is the therapy carried out?

Non-stenosing atherosclerosis in the early stages is treatable. With an integrated approach and strict observance of all the prescriptions of a specialist, it is possible to restrain the development of the disease.

The following methods are currently the most effective:

Medical treatment. It involves taking specialized medications.
Surgical intervention. This procedure is associated with a risk to the life and health of the patient. It is used only in severe cases, when all other methods of treatment are ineffective. Non-stenosing atherosclerosis is not surgically treated.
Lifestyle adjustment. To stop the development of the disease, it is necessary to give up bad habits, especially smoking. You should minimize the consumption of fatty, fried, smoked foods. You need to move more, go in for sports, enroll in the pool. In this case, the load should be moderate. It is best to consult with a specialist.
Diet food. Experts recommend adhering to special dietary rules. This will help reduce the amount of cholesterol entering the body.
exercise therapy. There is a specialized set of exercises that helps restore normal blood supply to all segments of the brain and limbs.
Health monitoring. It is necessary to regularly measure blood pressure, monitor the concentration of cholesterol in the blood. All comorbidities should be treated promptly.

Successful treatment is possible only if all negative factors are eliminated. The patient should avoid stressful situations, eat right and walk more in the fresh air. At the same time, it is imperative to strictly follow all the recommendations of the doctor.

What medicines are used for therapy

Today, several groups of drugs have been developed that have a positive effect in the treatment of atherosclerosis of the main vessels of the brain:

Antiplatelet agents. Drugs of this type prevent blood platelets from sticking together, which reduces the risk of developing thrombosis. Such funds are prohibited for use in renal and hepatic insufficiency, pregnancy, peptic ulcer and hemorrhagic stroke. The most popular drugs in this group are Trombo-ass, Cardiomagnyl, Plavix and so on.
Drugs that reduce blood viscosity. They help blood flow better through narrowed places. These include Sulodexide. Phlogenzym and others.
Preparations based on nicotinic acid. They are designed to improve circulation.
Medications that lower the concentration of cholesterol in the blood. With their help, non-stenosing atherosclerosis can be effectively treated. Among them are Crestor, Torvacard and others.
Means to enhance collateral circulation. This group includes Solcoseryl, Actovegin and some others.
Drugs to relieve symptoms. It can be anti-inflammatory and analgesics.

Drug therapy will take at least two to three months. Specific dosage and duration of therapy is determined by a specialist for each patient.

Patients suffering from atherosclerosis of the arteries of the brain are shown a life-long intake of acetylsalicylic acid. These drugs will help minimize the risk of developing thrombosis.

Treatment with surgical methods

Cerebral atherosclerosis in severe cases is treated with surgical intervention. This technique is used in the stenosing type of the disease. There are three main ways to carry out the operation:

Shunting. During this operation, the surgeon creates an additional blood flow near the damaged area. Thus, it is possible to restore normal blood flow.
Stenting. This operation involves the installation of a special implant, with which it is possible to restore normal blood flow.
Balloon angioplasty. The procedure involves the introduction of a specialized cartridge into the vessel. Pressure is applied to it, which expands the affected vessel.

A specific technique is chosen by a specialist based on the patient's state of health, as well as in which of the segments of the vascular system the lesion is localized.

Physiotherapy

Non-stenosing atherosclerosis responds well to treatment if the main therapy program is supplemented with physiotherapy exercises. It is best to conduct a lesson with a specialist.

But some exercises can be performed independently:

Walk with measured steps around the room. At the same time, make sure that your blood pressure does not rise.
Stand up straight. Exhale slowly and tilt your head back. At the same time, try to bend the cervical spine as much as possible. Hold this position for a couple of seconds. After that, slowly return to the starting position. Repeat the same procedure with the head tilted forward.
Stand up and straighten your spine as much as possible. Place your hands on your chest. On the count of one, raise your hands up, stretch to the ceiling. On the count of two, return to the starting position. Repeat this exercise 12 times.
Stand up straight. Make slow tilts of the body to the left and right sides. Make sure that the slope is made on the exhale, and return to the starting point on the inhale.
Sit in a high back chair. Try to relax. On the count of one, take one leg out to the side. Return to the original pose. Repeat the same steps with the other leg.

By repeating these exercises regularly, you can alleviate the course of the disease. They allow you to stimulate blood circulation and increase the tone of the vascular wall.

Folk methods of treatment

You can supplement the main therapy program with the help of traditional medicine. They cannot act as the only way of therapy.

Among the most effective recipes against atherosclerosis are:

Dilute a teaspoon of birch buds in a glass of boiling water. Boil the resulting composition for 25 minutes. After that, leave the product for a couple of hours to infuse. Take the prepared composition three times a day in an amount of 100 ml.
Pour a teaspoon of dried hawthorn flowers into a glass of water. This composition must be boiled for about 25 minutes. After that, it can be filtered. Wait until the broth cools down. It is taken in half a glass three times a day.
Squeeze the juice from one onion. Combine it with natural honey. One spoonful of honey is needed for one spoonful of juice. Add some water to make the composition liquid. It is necessary to take such a remedy one spoonful three times a day.

Such simple remedies will help enhance the effectiveness of traditional treatment. Sometimes they can provoke allergic reactions, so you should consult your doctor before using them.

Dietary diet

During treatment, patients with atherosclerosis are shown to follow a special diet. This is the only way to reduce the amount of cholesterol in the blood. You must adhere to the following recommendations:

The use of foods enriched with iodine, such as seaweed, is recommended.
A complete rejection of animal fats is shown. The lack of protein can be filled with legumes.
Eat more diuretic foods. These include watermelons, apples, melons and others.
The diet should include more vegetables, fruits, nuts, berries.
Chicken and turkey are allowed. Fatty meats, as well as offal are strictly prohibited.
You will have to give up sweets, coffee, strong tea, chocolate, canned foods.

Compliance with the principles of proper nutrition will help to stop the development of the disease and enhance the effect of medicines. At the first manifestations of atherosclerosis, you should immediately seek help from a specialist. The sooner a problem is identified, the greater the likelihood of maintaining health.

Atherosclerosis of the arteries of the lower extremities and its treatment

With atherosclerotic changes, cholesterol is deposited in the wall of blood vessels. Then it sprouts with connective tissue and a plaque is formed, which narrows the lumen of the artery and prevents the blood supply to the organ or tissue. In the structure of all target organs, this pathological process is most often formed in the vessels of the heart, the second place belongs to the vessels of the neck and brain. Atherosclerosis of the arteries of the lower extremities occupies an honorable third place, both in terms of frequency of occurrence and significance.

Risk factors

Since atherosclerosis is a systemic disease, the causes of damage to various arteries, including the lower extremities, are similar. They include:

smoking;
obesity and hyperlipidemia;
hereditary factor;
nervous tension;
hormonal disorders (climax);
diabetes;
hypertension.

A necessary condition for the formation of a plaque is a combination of risk factors and local changes in the artery wall, as well as the sensitivity of receptors. Atherosclerosis of the vessels of the lower extremities develops somewhat more often against the background of local pathologies (condition after frostbite, trauma, surgery).

Classification

The classification of atherosclerosis of the arteries of the lower extremities is based on the degree of impaired blood flow and manifestations of ischemia. There are four stages of the disease:
At the initial stage, pain in the legs is provoked only by severe physical exercises. In the second degree of blood flow disturbance, pain occurs when walking for about 200 meters.
At the third stage of the pathological process, the patient is forced to stop every 50 meters.
The terminal stage is characterized by the appearance of trophic changes in tissues (skin, muscles), up to gangrene of the legs.

The nature of the lesion can be stenosing, when the plaque only covers the lumen, or occlusive, if the artery is completely closed. The latter type usually develops with acute thrombosis of the damaged plaque surface. In this case, the development of gangrene is more likely.

Manifestations

The main symptom of damage to the vessels of the legs is pain in the calf muscles that occurs during exercise or at rest.
In another way, this symptom is called intermittent claudication, and it is associated with ischemia of muscle tissue. With atherosclerosis of the aorta in its terminal section, the symptoms are supplemented by pain in the muscles of the buttocks, thighs and even the lower back. In half of patients with Leriche's syndrome, there is a violation of pelvic functions, including impotence.

Very often, in the initial stages, the disease is asymptomatic. In some cases, there may be a violation of the blood supply to the surface tissues, which consists in cooling the skin and changing its color (pallor). Paresthesias are also characteristic - crawling, burning sensations and other sensations associated with hypoxia of nerve fibers.

As the disease progresses, the nutrition of the tissues of the lower extremities deteriorates, and non-healing trophic ulcers appear, which are harbingers of gangrene.

With acute occlusion of the arteries, an intense pain syndrome occurs, the affected limb becomes colder and paler than a healthy one. In this case, decompensation of the blood supply and tissue necrosis occur quite quickly. Such differences in the rate of onset of symptoms are due to the fact that during the chronic process, collaterals have time to form, which maintain the blood supply at an acceptable level. It is due to them that sometimes with occlusion of the artery, the signs of the disease are slightly expressed.

Diagnostic methods

During a routine examination of the patient, one can suspect a violation of the blood supply, which is manifested by a cooling of the affected limb, a change in its color (at first it turns pale, then becomes purple). Below the constriction, the pulsation is markedly weakened or completely absent. In the terminal stage of the process, trophic changes in the skin and gangrene appear.

Angiography is the most informative method for instrumental diagnosis of atherosclerosis. During it, a contrast agent is injected into the femoral artery, and then, under the control of x-rays, an image is taken. Thanks to angiography, you can clearly see all the narrowing in the vessels and the presence of collaterals. This manipulation is invasive and contraindicated in patients with severe renal insufficiency and allergy to iodine.

Doppler ultrasound is the simplest and most informative diagnostic method that allows you to determine the percentage of narrowing of the artery in 95% of cases. During this study, a drug test may be performed. After the introduction of nitroglycerin, the spasm of the vessel becomes less, which makes it possible to determine the functional reserve.

An additional diagnostic method is tomography with contrast and determination of the ankle-brachial index. The latter is calculated based on data on the pressure on the brachial artery and the vessels of the lower leg. By the degree of decrease in this indicator, one can almost always judge the severity of the lesion.

Treatment

Treatment of atherosclerosis of the vessels of the lower extremities becomes much more effective if it is possible to convince the patient of the need to give up bad habits, in particular smoking. At the same time, it is desirable to maintain a healthy lifestyle and try to reduce the influence of other risk factors. An important role is played by the observance of a special diet designed for patients with atherosclerosis. At the same time, nutrition should be complete and balanced, but the intake of animal fats and fried foods should be limited.

Therapeutic

Among the drugs used for atherosclerosis of the vessels of the legs, the most important are:

Disaggregates (aspirin) that prevent the formation of blood clots on the surface of the endothelium or damaged plaque.
Drugs that improve the rheological (fluid) properties of blood. These include reopoliglyukin and pentoxifylline. With decompensated ischemia, they are administered intravenously, then switching to the use of tablets.
Antispasmodics (no-shpa), which reduce the narrowing of the artery and thereby improve blood circulation.
Anticoagulants (heparin) are prescribed during the period of decompensation or in acute thrombosis.
In some cases, thrombolytics (streptokinase, actilyse) are used, but their use is limited due to the possible development of bleeding and insufficient effectiveness.

Additional methods of therapeutic action are hyperbaric oxygenation, which increases blood oxygen saturation, physiotherapy and treatment with the use of ozone.

Surgical

In atherosclerosis of the vessels of the lower extremities, accompanied by severe tissue malnutrition, surgical treatment is the most effective.

With minimally invasive intervention, manipulations are carried out through a puncture in the vessel. A special balloon is inflated at the narrowing site, and then the result is fixed by placing a metal stent. You can also perform the removal of blood clots, after crushing them.

In open operations, the inner lining of the vessel is removed along with atherosclerotic deposits, as well as thrombectomy. In the case of an extended lesion, bypass shunts are applied using own vessels or artificial prostheses. Most often, such operations are performed with a serious narrowing of the terminal aorta or femoral arteries. The operation in this case is called aorto-femoral prosthesis.

Palliative treatments can somewhat reduce the symptoms of the disease and improve collateral circulation. These include laser perforation, revascularizing osteotrepanation, lumbar sympathectomy, and some others.

With the development of gangrene, the limb is amputated within healthy tissues.

Folk methods

The following methods of alternative treatment of this pathology are most widely used:

decoctions from various herbs (common hops, horse chestnut), which must be taken orally to improve blood flow;
phytoparabochka, which includes mint, dandelion, motherwort and viburnum;
nettle baths improve microcirculation and reduce the symptoms of atherosclerosis.

It should be remembered that these methods are auxiliary and do not replace, but only supplement traditional treatment.

Stenosing atherosclerosis is a manifestation of the systemic formation of cholesterol plaques, characterized by impaired blood flow through the arteries of the lower extremities. The disease is irreversible and constantly progressing, so there is no cure. By following a diet and eliminating risk factors for atherosclerosis, it is possible to slow down the process, and by applying bypass shunts, to delay the appearance of trophic tissue changes. The prognosis of the disease is determined by the degree of concomitant damage to the vessels of the heart and brain by atherosclerosis.

Collateral circulation is an important functional adaptation of the body, associated with the high plasticity of blood vessels and ensuring uninterrupted blood supply to organs and tissues. Its deep study, which is of great practical importance, is associated with the name of V. N. Tonkov and his school (R. A. Bardina, B. A. Dolgo-Saburov, V. V. Ginzburg, V. N. Kolesnikov, V. P. Kurkovsky, V. P. Kuntsevich, I. D. Lev, F. V. Sudzilovsky, S. I. Shchelkunov, M. V. Shepelev, etc.).

From the foregoing, it is necessary to clearly define the difference between anastomoses and collaterals.

Anastomosis(anastomoo, Greek - I supply the mouth) - an anastomosis is any third vessel that connects the other two - an anatomical concept.

Collateral(collateralis, lat. - lateral) - this is a lateral vessel that carries out a roundabout blood flow; concept - anatomical and physiological.

Collaterals are of two kinds. Some exist normally and have the structure of a normal vessel, like anastomosis. Others develop again from anastomoses and acquire a special structure.

These anastomoses have already been noted in the course of presentation of the arteries.

In addition, thin arteries and veins take part in the collateral circulation, accompanying the main vessels in the neurovascular bundles and making up the so-called perivascular and perinervous arterial and venous bed(A. T. Akilova).

Anastomoses, in addition to their practical significance, are an expression of the unity of the arterial system, which, for the convenience of study, we artificially divide into separate parts.

Veins of the systemic circulation

Superior vena cava system

Vena cava superior, superior vena cava, is a thick (about 2.5 cm), but short (5-6 cm) trunk, located on the right and somewhat behind the ascending aorta. The superior vena cava is formed from the confluence vv. brachiocephalicae dextra et sinistra behind the junction of the 1st right rib with the sternum. From here it descends along the right edge of the sternum behind the first and second intercostal spaces and at the level of the upper edge of the third rib, hiding behind the right ear of the heart, flows into the right atrium. With its back wall, it is in contact with a. pulmonalis dextra, separating it from the right bronchus, and for a very short distance, at the place where it flows into the atrium, with the upper right pulmonary vein; both of these vessels cross it transversely. At the level of the upper edge of the right pulmonary artery, v flows into the superior vena cava. azygos, bending over the root of the right lung (the aorta bends through the root of the left lung). The anterior wall of the superior vena cava is separated from the anterior chest wall by a fairly thick layer of the right lung.

Brachiocephalic veins

Vv. brachiocephalicae dextra et sinistra, brachiocephalic veins, from which the superior vena cava is formed, in turn, each is obtained by merging v. subclaviae and v. jugularis internae. The right brachiocephalic vein is shorter than the left, only 2-3 cm long; having formed behind the right sternoclavicular joint, it goes obliquely down and medially to the confluence with the saphenous vein of the left side. In front, the right brachiocephalic vein is covered by mm. sternocleidomastoideus, sternohyoideus and sternothyreoideus, and below the cartilage of the 1st rib. The left brachiocephalic vein is approximately twice as long as the right. Formed behind the left sternoclavicular joint, it goes behind the handle of the sternum, separated from it only by fiber and the goiter gland, to the right and downward to the confluence with the right brachiocephalic vein; while closely adhering with its lower wall to the bulge of the aortic arch, it crosses in front the left subclavian artery and the initial parts of the left common carotid artery and the brachiocephalic trunk. Vv flows into the brachiocephalic veins. thyreoideae inferiors et v. thyreoidea ima, formed from a dense venous plexus at the lower edge of the thyroid gland, vein of the thymus gland, vv. vertebrates, cervicales et thoracicae internae.

Internal jugular vein

V. jugularis interna, internal jugular vein(Fig. 239, 240), removes blood from the cranial cavity and neck organs; starting at the foramen jugulare, in which it forms an extension, bulbus superior venae jugularis internae, the vein descends, located laterally from a. carotis interna and further down laterally from a. carotis communis. At the lower end v. jugularis internae before connecting it with v. subclavia, a second thickening is formed - bulbus inferior v. jugularis internae; in the neck above this thickening in the vein there is one or two valves. On its way to the neck, the internal jugular vein is covered by mm. sternocleidomastoideus and omohyoideus. About the sinuses pouring blood into v. jugularis interna, see the section on the brain. Here it is necessary to mention vv. ophthalmicae superior et inferior, which collect blood from the orbit and flow into the sinus cavernosus, with v. ophthalmica inferior also connects to the plexus pterygoideus (see below).

On the way v. jugularis interna receives the following tributaries:

1. V. facialis, facial vein. Its tributaries correspond to branches a. facialis.

2. V. retromandibularis, retromaxillary vein, collects blood from the temporal region. Further down in v. retromandibularis, the trunk flows into it, carrying blood from the plexus pterygoideus (dense plexus between mm. pterygoidei), after which v. retromandibularis, passing through the thickness of the parotid gland together with the external carotid artery, merges with v. facialis.

The shortest path connecting the facial vein with the pterygoid plexus is the "anastomotic vein" (v. anastomotica facialis) described by M. A. Sreseli, which is located at the level of the alveolar margin of the lower jaw.

3. Vv. pharyngeae, pharyngeal veins, forming a plexus (plexus pharyngeus) on the pharynx, or pour directly into v. jugularis interna, or they fall into v. facialis.

4. V. lingualis, lingual vein, accompanies the artery of the same name.

5. Vv. thyreoideae superiores, superior thyroid veins, collect blood from the upper sections of the thyroid gland and larynx.

6. V. thyreoidea media, middle thyroid vein(or rather, lateralis, according to N. B. Likhacheva), departs from the lateral edge of the thyroid gland and merges into v. jugularis interna. At the lower edge of the thyroid gland there is an unpaired venous plexus - plexus thyreoideus impar, the outflow from which occurs through vv. thyreoideae superiores in v. jugularis interna, as well as no vv. thyreoideae inferiores and v. thyreoidea ima into the veins of the anterior mediastinum.

External jugular vein

V. jugularis externa, external jugular vein(see Fig. 239, 240 and 241), starting behind the auricle and leaving at the level of the angle of the jaw from the region of the posterior jaw fossa, descends, covered with m. platysma, along the outer surface of the sternocleidomastoid muscle, crossing it obliquely downwards and backwards. Having reached the posterior edge of the sternocleidomastoid muscle, the vein enters the supraclavicular region, where it usually flows into a common trunk with v. jugularis anterior into the subclavian vein. Behind the auricle in v. jugularis externa flow into v. auricularls posterior and v. occipitalis.

Anterior jugular vein

V. jugularis anterior, anterior jugular vein, is formed from small veins above the hyoid bone, from where it descends vertically downward. Both v.v. jugulares anteriores, right and left, pierce the deep leaf of fascia colli propriae, enter spatium interaponeuroticum suprasternal and flow into the subclavian vein. In the suprasternal space, both vv. jugulares anteriores anastomose with one or two trunks. Thus, a venous arch is formed above the upper edge of the sternum and collarbones, the so-called drcus venosus jdgult. In some cases vv. jugulares anteriores are replaced by one unpaired v. jugularis anterior, which descends along the midline and merges below into the mentioned venous arch, which is formed in such cases from the anastomosis between vv. jugulares externae (see Fig. 239).

subclavian vein

V. subclavia, subclavian vein, is a direct continuation of v. axillaris. It is located anterior and downward from the artery of the same name, from which it is separated by m. scalenus anterior; behind the sternoclavicular joint, the subclavian vein merges with v. jugularis interna, and v. is formed from the confluence of these veins. brachiocephalica.

Veins of the upper limb

The veins of the upper limb are divided into deep and superficial.

Surface, or subcutaneous, veins, anastomosing with each other, form a wide-loop network, from which larger trunks separate in places. These trunks are as follows (Fig. 242):

1. V. cephalica* begins in the radial section of the rear of the hand, along the radial side of the forearm reaches the elbow, anastomosing here with v. basilica, goes along sulcus bicipitalis lateralis, then perforates the fascia and flows into v. axillaris.

* (The cephalic vein, since it was believed that when it was opened, blood was diverted from the head.)

2. V. basilica* starts on the ulnar side of the back of the hand, goes in the medial section of the anterior surface of the forearm along m. flexor carpi ulnaris to the elbow, anastomosing here with v. cephalica through v. mediana cubity; then lies in the sulcus bicipitalis medialis, perforates the fascia on half the length of the shoulder and merges into v. brachialis.

* (Royal vein, as it was opened in diseases of the liver, which was considered the queen of the body.)

3. V. mediana cubiti, median vein of the cubital region, is an oblique anastomosis connecting v. basilica and v. cephalica. V usually flows into it. mediana antebrdchii, which carries blood from the palmar side of the hand and forearm. V. mediana ciibiti is of great practical importance, as it serves as a place for intravenous infusion of drugs, blood transfusion and taking it for laboratory research.

deep veins accompany the arteries of the same name, usually two each. Thus, there are two: vv. brachiales, ulnares, radiales, interosseae.

Both v.v. brachiales at the lower edge of m. pectoralis major merge together and form the axillary vein, v. axillaris, which in the axillary fossa lies medially and anterior to the artery of the same name, partly covering it. Passing under the clavicle, it continues further in the form of v. subclavia. In v. axillaris, except for the above v. cephalica, flows into v. thoracoacromialis(corresponds to the artery of the same name), v. thoracica lateralis(in which v. thoracoepigastrica, a large trunk of the abdominal wall, often flows), v. subscapularis, vv. circumflexae humeri.

Veins - unpaired and semi-unpaired

V. azygos, unpaired vein, and v. hemiazygos, semi-unpaired vein, are formed in the abdominal cavity from the ascending lumbar veins, vv. lumbdles ascendentes, connecting the lumbar veins in the longitudinal direction. They go up behind m. psoas major and penetrate into the chest cavity between the muscle bundles of the legs of the diaphragm: v. azygos - together with the right n. splanchnicus v. hemiazygos - with left n. splanchnicus or sympathetic trunk.

In the chest cavity v. azygos rises along the right lateral side of the spine, closely adjacent to the posterior wall of the esophagus. At the level of the IV or V vertebra, it departs from the spine and, bending over the root of the right lung, flows into the superior vena cava. In addition to the branches that carry blood from the mediastinal organs, nine right lower intercostal veins flow into the unpaired vein and through them the veins of the vertebral plexuses. Near the place where the unpaired vein bends over the root of the right lung, it takes in v. intercostdlis superior dextra, formed from the confluence of the upper three right intercostal veins (Fig. 243).

On the left lateral surface of the vertebral bodies behind the descending thoracic aorta lies v. hemiazygos. It rises only to the VII or VIII thoracic vertebra, then turns to the right and, passing obliquely upward along the anterior surface of the spine behind the thoracic aorta and ductus thoracicus, merges into v. azygos. It receives branches from the mediastinal organs and the lower left intercostal veins, as well as the veins of the vertebral plexuses. The upper left intercostal veins join v. hemiazygos accessoria, which goes from top to bottom, located in the same way as v. hemiazygos, on the left lateral surface of the vertebral bodies, and merges either into v. hemiazygos, or directly in v. azygos, bending over to the right through the anterior surface of the body of the VII thoracic vertebra.

Veins of the body walls

Vv. intercostales posteriores, posterior intercostal veins, accompany in the intercostal spaces the arteries of the same name, one vein for each artery. The confluence of the intercostal veins into the unpaired and semi-unpaired veins was mentioned above. In the posterior ends of the intercostal veins near the spine flow: ramus dorsalis (a branch that carries blood from the deep muscles of the back) and ramus spinalis (from the veins of the vertebral plexuses).

V. thoracica interna, internal thoracic vein, accompanies the artery of the same name; being double for most of its length, however, near the I rib it merges into one trunk, which flows into v. brachiocephaiica of the same side.

The initial department of her, v. epigastrica superior, anastomoses with v. epigastrica inferior (flows into v. iliaca externa), as well as with the saphenous veins of the abdomen (vv. subcutaneae abdominis), which form a large-loop network in the subcutaneous tissue. From this network, blood flows upward through v. thoracoepigastrica et v. thoracica lateralis in v. axillaris, and downwards the blood flows through v. epigastrica superficialis and v. circumflexa ilium superficialis into the femoral vein. Thus, the veins in the anterior abdominal wall form a direct connection between the branches of the superior and inferior vena cava. In addition, in the umbilical region, several venous branches are connected through vv. paraumbilicales with the portal vein system (see below for more on this).

Vertebral plexus

There are four venous vertebral plexuses - two internal and two external. Internal plexuses, plexus venosi vertebrates interni (anterior et posterior) are located in the spinal canal and consist of a number of venous rings, one for each vertebra. The veins of the spinal cord flow into the internal vertebral plexuses, as well as vv. basivertebral, emerging from the vertebral bodies on their posterior surface and carrying blood from the spongy substance of the vertebrae. external vertebral plexus, plexus venosi vertebrates externi, are divided in turn into two: the anterior - on the anterior surface of the vertebral bodies (developed mainly in the cervical and sacral regions), and the posterior, lying on the arches of the vertebrae, covered with deep dorsal and cervical muscles. Blood from the vertebral plexuses is poured into the trunk area through vv. intervertebrales in vv. intercostales post, and vv. lumbales. In the neck area, outflow occurs mainly in v. vertebralis, which, going along with a. vertebralis, merges into v. brachiocephalica, independently or previously connected with v. cervicalis profunda.

Inferior vena cava system

V. cava inferior, inferior vena cava, the thickest venous trunk in the body, lies in the abdominal cavity next to the aorta, to the right of it. It is formed at the level of the IV lumbar vertebra from the confluence of two common iliac veins slightly below the aortic division and immediately to the right of it. The inferior vena cava goes up and somewhat to the right, so that the farther up, the more it departs from the aorta. Below the vein is adjacent to the medial edge of the right m. psoas, then passes to its front surface and lies at the top on the lumbar part of the diaphragm. Then, lying in the sulcus venae cavae on the posterior surface of the liver, the inferior vena cava passes through the foramen venae cavae of the diaphragm into the chest cavity and immediately flows into the right atrium.

The tributaries flowing directly into the inferior vena cava correspond to the paired branches of the aorta (except vv. hepaticae). They are divided into parietal veins and veins of the viscera.

Parietal veins: 1) vv. lumbales dextrae and sinistrae, four on each side, correspond to the arteries of the same name, receive anastomoses from the vertebral plexuses; they are interconnected by longitudinal trunks, vv. lumbales ascendentes; 2) vv. phrenicae inferiores flow into the inferior vena cava where it passes in the groove of the liver.

Veins of the viscera: 1) vv. testiculares in men ( vv. ovaricae in women) begin in the testicles and braid the arteries of the same name in the form of a plexus (plexus pampiniformis); right v. testicularis flows directly into the inferior vena cava at an acute angle, while the left - into the left renal vein at a right angle. This last circumstance complicates, according to Girtl, the outflow of blood and causes a more frequent occurrence of the expansion of the veins of the left spermatic cord in comparison with the right one (in a woman, v. ovarica begins at the hilum of the ovary); 2) vv. renales, renal veins, go ahead of the arteries of the same name, almost completely covering them; the left is longer than the right and passes in front of the aorta; 3) v. suprarenalis dextra flows into the inferior vena cava immediately above the renal vein; v. suprarenalis sinistra usually does not reach the vena cava and flows into the renal vein in front of the aorta; four) vv. hepaticae, hepatic veins, flow into the inferior vena cava where it passes along the posterior surface of the liver; the hepatic veins carry blood out of the liver, where blood enters through the portal vein and the hepatic artery (see Fig. 141).

Portal vein

The portal vein collects blood from all unpaired organs of the abdominal cavity, with the exception of the liver: from the entire gastrointestinal tract, where nutrients are absorbed, which enter the liver through the portal vein to neutralize and deposit glycogen; from the pancreas, where insulin comes from, which regulates sugar metabolism; from the spleen, where the breakdown products of blood cells come from, used in the liver to produce bile. The constructive connection of the portal vein with the gastrointestinal tract and its large glands (liver and pancreas) is due, in addition to the functional connection, and the commonality of their development (genetic connection) (Fig. 245).

V. portae, portal vein, represents a thick venous trunk located in lig. hepatoduodenal along with the hepatic artery and ductus choledochus. Folds v. portae behind the head of the pancreas splenic vein and two mesenteric - upper and lower. Heading to the porta of the liver in the mentioned ligament of the peritoneum, it takes vv along the way. gdstricae sinistra et dextra and v. prepylorica and at the gate of the liver is divided into two branches that go into the liver parenchyma. In the parenchyma of the liver, these branches break up into many small branches that braid the hepatic lobules (vv. interlobulares); numerous capillaries penetrate into the lobules themselves and eventually form into vv. centrales (see "Liver"), which are collected in the hepatic veins, which flow into the inferior vena cava. Thus, the portal vein system, unlike other veins, is inserted between two networks of capillaries: the first network of capillaries gives rise to the venous trunks that make up the portal vein, and the second is located in the substance of the liver, where the portal vein splits into its terminal branches.

V. liertalis, splenic vein, carries blood from the spleen, from the stomach (through v. gastroepiploica sinistra and vv. gastricae breves) and from the pancreas, along the upper edge of which, behind and below the artery of the same name, it goes to v. portae.

Vv. mesentericae superior et inferior, superior and inferior mesenteric veins, correspond to the arteries of the same name. V. mesenterica superior on its way takes in venous branches from the small intestine (vv. intestinales), from the caecum, from the ascending colon and transverse colon (v. colica dextra et v. colica media) and, passing behind the head of the pancreas , connects to the inferior mesenteric vein. V. mesenterica inferior starts from the venous plexus of the rectum, plexus venosus rectalis. Heading up from here, on the way it receives inflows from the sigmoid colon (vv. sigmoideae), from the descending colon (v. colica sinistra) and from the left half of the transverse colon. Behind the head of the pancreas, it, having previously connected with the splenic vein or independently, merges with the superior mesenteric vein.

Common iliac veins

Vv. iliacae communes, common iliac veins, right and left, merging with each other at the level of the lower edge of the IV lumbar vertebra, form the inferior vena cava. The right common iliac vein is located behind the artery of the same name, while the left one lies only below the artery of the same name, then lies medially from it and passes behind the right common iliac artery to merge with the right common iliac vein to the right of the aorta. Each common iliac vein at the level of the sacroiliac joint, in turn, is composed of two veins: the internal iliac ( v. iliaca interna) and external iliac ( v. iliaca externa).

Internal iliac vein

V. iliaca interna, internal iliac vein, in the form of a short but thick trunk, is located behind the artery of the same name. The tributaries that make up the internal iliac vein correspond to the arterial branches of the same name, and usually these tributaries are double in number outside the pelvis; when they enter the pelvis, they become solitary. In the region of the tributaries of the internal iliac vein, a number of venous plexuses are formed, anastomosing with each other.

1. Plexus venosus sacralis It is composed of sacral veins - lateral and median.

2. Plexus venosus rectalis s. hemorrhoidalis (BNA) - a plexus in the walls of the rectum. There are three plexuses: submucosal, subfascial and subcutaneous. The submucosal, or internal, venous plexus, plexus rectalis interims, in the region of the lower ends of the columnae rectalis is a series of venous nodules arranged in the form of a ring. The efferent veins of this plexus pierce the muscular membrane of the intestine and merge with the veins of the subfascial, or external, plexus, plexus rectalis externus. From the latter comes v. rectalis superior and vv. rectales mediae accompanying the corresponding arteries. The first through the inferior mesenteric vein flows into the portal vein system, the second - into the system of the inferior vena cava, through the internal iliac vein. In the region of the external sphincter of the anus, a third plexus is formed, subcutaneous - plexus subcutaneus ani, from which vv. rectales inferiores flowing into v. pudenda interna.

3. Plexus venosus vesicalis located in the area of the bottom of the bladder; through vv. vesicales, blood from this plexus drains into the internal iliac vein.

4. Plexus venosus prostaticus located between the bladder and the pubic fusion, covering the prostate gland and seminal vesicles in a man. Unpaired v. joins the plexus venosus prostaticus. dorsalis penis. In a woman, the dorsal vein of the penis of a man corresponds to v. dorsalis clitoridis.

5. Plexus venosus uterinus and plexus venosus vaginalis women are located in wide ligaments on the sides of the uterus and further down along the side walls of the vagina; blood is poured out of them partly through the ovarian vein (plexus pampiniformis), mainly through v. uterina into the internal iliac vein.

Porto-caval and caval anastomoses

The roots of the portal vein anastomose with the roots of the veins belonging to the systems of the superior and inferior vena cava, forming the so-called portocaval anastomoses, which are of practical importance.

If we compare the abdominal cavity with a cube, then these anastomoses will be on all its sides, namely:

1. Above, in the pars abdominalis of the esophagus - between the roots of v. gastricae sinistrae, which flows into the portal vein, and vv. esophageae flowing into vv. azygos and hemyazygos and further into v. cava superior.

2. Below, in the lower part of the rectum, between v. rectalis superior, flowing through v. mesenterica inferior into the portal vein, and vv. rectales media (tributary v. iliaca interna) et inferior (tributary v. pudenda interna), flowing into v. iliaca interna and beyond v. iliaca communis - from v. cava inferior.

3. In front, in the umbilical region, where vv. paraumbilicales, going in the thickness of lig. teres hepatis to the portal vein, v. epigastrica superior from v. cava superior (v. thoracica interna, v. brachiocephalica) and v. epigastrica inferior - from the system v. cava inferior (v. iliaca externa, v. iliaca communis).

It turns out porto-caval and caval anastomoses, which have the value of a roundabout way of outflow of blood from the portal vein system when there are obstacles for it in the liver (cirrhosis). In these cases, the veins around the umbilicus dilate and take on a characteristic appearance ("jellyfish's head") * .

* (Extensive connections of the veins of the goiter and thyroid glands with the veins of the surrounding organs are involved in the formation of cavacaval anastomoses (N. B. Likhacheva).)

4. Behind, in the lumbar region, between the roots of the veins of the mesoperitoneal sections of the colon (from the portal vein system) and parietal vv. lumbales (from the v. cava inferior system). All these anastomoses form the so-called Retzius system.

5. In addition, there is a cavacaval anastomosis between the vv roots on the posterior abdominal wall. lumbales (from the v. cava inferior system), which are associated with the pair v. lumbalis ascendens, which is the beginning of vv. azygos (right) et hemiazygos (left) (from the v. cava superior system).

6. Cavacaval anastomosis between vv. lumbales and intervertebral veins, which in the neck are the roots of the superior vena cava.

External iliac vein

V. iliaca externa is a direct continuation of v. femoralis, which, after passing under the pupart ligament, is called the external iliac vein. Going medially from the artery and behind it, it merges with the internal iliac vein in the region of the sacroiliac joint and forms the common iliac vein; receives two tributaries, sometimes flowing in one trunk: v. epigastric inferior and v. circumflexa ilium profunda accompanying the arteries of the same name.

Veins of the lower limb. As in the upper limb, the veins of the lower limb are divided into deep and superficial, or subcutaneous, which pass independently of the arteries.

deep veins the feet and lower legs are double and accompany the arteries of the same name. V. poplitea, which is composed of all the deep veins of the lower leg, is a single trunk located in the popliteal fossa posteriorly and somewhat laterally from the artery of the same name. V. femoralis, solitary, initially located laterally from the artery of the same name, then gradually passes to the posterior surface of the artery, and even higher to its medial surface, and in this position passes under the pupart ligament in the lacuna vasorum. Tributaries v. femoralis are all double.

From the saphenous veins of the lower limb, the largest are two trunks: v. saphena magna and v. saphena parva. Vena saphena magna originates on the dorsal surface of the foot from rete venosum dorsale pedis and arcus venosus dorsalis pedis. Having received several tributaries from the side of the sole, it goes up the medial side of the lower leg and thigh. In the upper third of the thigh, it bends onto the anteromedial surface and, lying on the wide fascia, goes to the hiatus saphenus. In this place v. saphena magna flows into the femoral vein, spreading through the lower horn of the sickle-shaped edge. Quite often v. saphena magna is double, and both of its trunks can flow separately into the femoral vein. Of the other subcutaneous tributaries of the femoral vein, mention should be made of v. epigastrica superficialis, v. circumflexa ilium superficialis, vv. pudendae externae accompanying the arteries of the same name. They pour partly directly into the femoral vein, partly into v. saphena magna at the place of its confluence in the region of hiatus saphenus. V. saphena parva starts on the lateral side of the dorsal surface of the foot, goes around the bottom and behind the lateral ankle and rises further along the back surface of the lower leg; first, it goes along the lateral edge of the Achilles tendon, and then upward along the middle of the posterior part of the lower leg, corresponding to the groove between the heads of m. gastrocnemia. Having reached the lower angle of the popliteal fossa, v. saphena parva flows into the popliteal vein. V. saphena parva is connected by branches to v. saphena magna.