coronary artery. Atherosclerosis of the coronary arteries. What is the coronary artery, its anatomy

The arteries of the heart depart from the aortic bulb - the initial expanded section of the ascending aorta and, like a crown, surround the heart, in connection with which they are called coronary arteries. Right coronary artery begins at the level of the right sinus of the aorta, and the left coronary artery - at the level of its left sinus. Both arteries depart from the aorta below the free (upper) edges of the semilunar valves, therefore, during contraction (systole) of the ventricles, the valves cover the openings of the arteries and almost do not let blood flow to the heart. With relaxation (diastole) of the ventricles, the sinuses fill with blood, blocking its path from the aorta back to the left ventricle, and at the same time open the access of blood to the vessels of the heart.

Right coronary artery

It leaves to the right under the ear of the right atrium, lies in the coronary sulcus, goes around the right pulmonary surface of the heart, then follows its posterior surface to the left, where it anastomoses with its end with the circumflex branch of the left coronary artery. The largest branch of the right coronary artery is the posterior interventricular branch, which is directed along the sulcus of the same name towards the apex of the heart. The branches of the right coronary artery supply the wall of the right ventricle and atrium, the posterior part of the interventricular septum, the papillary muscles of the right ventricle, the posterior papillary muscle of the left ventricle, the sinoatrial and atrioventricular nodes of the cardiac conduction system.

Left coronary artery

A little thicker than the right. Located between the beginning of the pulmonary trunk and the left atrial appendage, it is divided into two branches: the anterior interventricular branch and the circumflex branch. The latter, which is a continuation of the main trunk of the coronary artery, goes around the heart on the left, located in its coronary sulcus, where it anastomoses with the right coronary artery on the posterior surface of the organ. The anterior interventricular branch follows the sulcus of the same name towards the apex of the heart. In the region of the cardiac notch, it sometimes passes to the diaphragmatic surface of the heart, where it anastomoses with the terminal section of the posterior interventricular branch of the right coronary artery. Branches of the left coronary artery supply the wall of the left ventricle, including the papillary muscles, most of the interventricular septum, the anterior wall of the right ventricle, and the wall of the left atrium.

The branches of the right and left coronary arteries, connecting, form two arterial rings in the heart: a transverse one, located in the coronary sulcus, and a longitudinal one, the vessels of which are located in the anterior and posterior interventricular sulci.

Branches of the coronary arteries provide blood supply to all layers of the walls of the heart. In the myocardium, where the level of oxidative processes is the highest, microvessels anastomosing with each other repeat the course of the bundles of muscle fibers of its layers.

There are various options for the distribution of branches of the coronary arteries, which are called types of blood supply to the heart. The main ones are as follows: right coronary, when most parts of the heart are supplied with blood by the branches of the right coronary artery; left coronary, when most of the heart receives blood from the branches of the left coronary artery, and medium, or uniform, in which both coronary arteries evenly participate in the blood supply to the walls of the heart. There are also transitional types of blood supply to the heart - middle right and middle left. It is generally accepted that among all types of blood supply to the heart, the middle right type is predominant.

Variants and anomalies of the position and branching of the coronary arteries are possible. They are manifested in changes in the places of origin and the number of coronary arteries. So, the latter can depart from the aopta directly above the semilunar valves or much higher - from the left subclavian artery and not from the aorta. The coronary artery may be the only one, that is, unpaired, there may be 3-4 coronary arteries, and not two: two arteries depart to the right and left of the aorta, or two from the aorta and two from the left subclavian artery.

Along with the coronary arteries, non-permanent (additional) arteries go to the heart (especially to the pericardium). These can be mediastinal-pericardial branches (upper, middle and lower) of the internal thoracic artery, branches of the pericardial phrenic artery, branches extending from the concave surface of the aortic arches, etc.

The main source of blood supply to the heart is coronary arteries(Fig. 1.22).

The left and right coronary arteries branch from the initial part of the ascending aorta in the left and right sinuses. The location of each coronary artery varies both in height and circumference of the aorta. The mouth of the left coronary artery can be at the level of the free edge of the semilunar valve (42.6% of cases), above or below its edge (in 28 and 29.4%, respectively).

For the mouth of the right coronary artery, the most common location is above the free edge of the semilunar valve (51.3% of cases), at the level of the free edge (30%) or below it (18.7%). The displacement of the orifices of the coronary arteries upward from the free edge of the semilunar valve is up to 10 mm for the left and 13 mm for the right coronary artery, down - up to 10 mm for the left and 7 mm for the right coronary artery.

In single observations, more significant vertical offsets mouths of the coronary arteries, up to the beginning of the aortic arch.

Rice. 1.22. The blood supply system of the heart: 1 - ascending aorta; 2 - superior vena cava; 3 - right coronary artery; 4 - LA; 5 - left coronary artery; 6 - a large vein of the heart

Towards middle line sinus, the mouth of the left coronary artery in 36% of cases is displaced to the anterior or posterior edge. A significant displacement of the beginning of the coronary arteries along the circumference of the aorta leads to the discharge of one or both coronary arteries from the sinuses of the aorta, which are unusual for them, and in rare cases, both coronary arteries come from one sinus. Changing the location of the orifices of the coronary arteries in height and circumference of the aorta does not affect the blood supply to the heart.

The left coronary artery is located between the beginning of the pulmonary trunk and the left auricle of the heart and is divided into circumflex and anterior interventricular branches.

The latter follows the apex of the heart, located in the anterior interventricular groove. The circumflex branch is directed under the left ear in the coronary sulcus to the diaphragmatic (posterior) surface of the heart. The right coronary artery, after leaving the aorta, lies under the right ear between the beginning of the pulmonary trunk and the right atrium. Then it turns along the coronal sulcus to the right, then back, reaches the posterior longitudinal sulcus, along which it descends to the apex of the heart, already being called the posterior interventricular branch. The coronary arteries and their large branches lie on the surface of the myocardium, located at different depths in the epicardial tissue.

The branches of the main trunks of the coronary arteries are divided into three types - main, loose and transitional. The main type of branching of the left coronary artery is observed in 50% of cases, loose - in 36% and transitional - in 14%. The latter is characterized by the division of its main trunk into 2 permanent branches - the envelope and the anterior interventricular. The loose type includes cases when the main trunk of the artery gives off the interventricular, diagonal, additional diagonal and circumflex branches at the same or almost the same level. From the anterior interventricular branch, as well as from the envelope, 4–15 branches depart. The angles of departure of both primary and subsequent vessels are different and range from 35–140°.

According to the International Anatomical Nomenclature, adopted at the Congress of Anatomists in Rome in 2000, the following vessels supplying the heart are distinguished:

Left coronary artery

Anterior interventricular branch (r. Interventricularis anterior)
Diagonal branch (r. diagonalis)
Branch of the arterial cone (r. coni arteriosi)
Lateral branch (r. lateralis)
Septal interventricular branches (rr. interventricularis septales)
Enveloping branch (r. circumflex exus)
Anastomotic atrial branch (r. atrialis anastomicus)
Atrioventricular branches (rr. atrioventricularis)
Left marginal branch (r. marginalis sinister)
Intermediate atrial branch (r. Atrialis intermedius).
Posterior LV branch (r. Posterior ventriculi sinistri)
Branch of the atrioventricular node (r. nodi atrioventricularis)

Right coronary artery

Branch of the arterial cone (ramus coni arteriosi)
Branch of the sinoatrial node (r. Nodi sinoatrialis)
Atrial branches (rr. atriales)
Right marginal branch (r. marginalis dexter)
Intermediate precordial branch (r. atrialis intermedius)
Posterior interventricular branch (r. interventricularis posterior)
Septal interventricular branches (rr. interventriculares septales)
Branch of the atrioventricular node (r. nodi atrioventricularis).

By the age of 15–18, the diameter of the coronary arteries (Table 1.1) approaches those of adults. At the age of over 75 years, there is a slight increase in the diameter of these arteries, which is associated with the loss of the elastic properties of the arterial wall. In most people, the diameter of the left coronary artery is larger than the right. The number of arteries extending from the aorta to the heart may decrease to 1 or increase to 4 due to additional coronary arteries, which are not normal.

The left coronary artery (LCA) originates in the posterior internal sinus of the aortic bulb, passes between the left atrium and the LA, and divides into the anterior interventricular and circumflex branches approximately 10–20 mm later.

The anterior interventricular branch is a direct continuation of the LCA and runs in the corresponding sulcus of the heart. Diagonal branches (from 1 to 4) depart from the anterior interventricular branch of the LCA, which are involved in the blood supply to the lateral wall of the left ventricle and can anastomose with the envelope branch of the left ventricle. The LCA gives off 6 to 10 septal branches that supply blood to the anterior two-thirds of the interventricular septum. The anterior interventricular branch of the LCA itself reaches the apex of the heart, supplying it with blood.

Sometimes the anterior interventricular branch passes to the diaphragmatic surface of the heart, anastomosing with the posterior interventricular artery of the heart, carrying out collateral blood flow between the left and right coronary arteries (with right or balanced types of blood supply to the heart).

Table 1.1

The right marginal branch used to be called the artery of the acute edge of the heart - ramus margo acutus cordis. The left marginal branch is the branch of the blunt edge of the heart - ramus margo obtusus cordis, since the well-developed LV myocardium of the heart makes its edge rounded, blunt).

Thus, the anterior interventricular branch of the LCA supplies the anterolateral wall of the left ventricle, its apex, most of the interventricular septum, and also the anterior papillary muscle (due to the diagonal artery).

The envelope branch, moving away from the LCA, located in the AV (coronary) groove, goes around the heart on the left, reaches the intersection and the posterior interventricular groove. The circumflex branch can either end at the obtuse edge of the heart or continue in the posterior interventricular sulcus. Passing in the coronary sulcus, the circumflex branch sends large branches to the lateral and posterior walls of the left ventricle. In addition, important atrial arteries depart from the circumflex branch (including r. nodi sinoatrialis). These arteries, especially the sinus node artery, anastomose abundantly with branches of the right coronary artery (RCA). Therefore, the branch of the sinus node is of "strategic" importance in the development of atherosclerosis in one of the main arteries.

The RCA originates in the anterior internal sinus of the aortic bulb. Departing from the anterior surface of the aorta, the RCA is located on the right side of the coronary sulcus, approaches the sharp edge of the heart, goes around it and goes to the crux and then to the posterior interventricular sulcus. At the intersection of the posterior interventricular and coronal sulci (crux), the RCA gives off the posterior interventricular branch, which goes towards the distal part of the anterior interventricular branch, anastomosing with it. Rarely, the RCA ends at the sharp edge of the heart.

The PCA supplies blood with its branches right atrium, part of the anterior and entire posterior surface of the LV, the interatrial septum and the posterior third of the interventricular septum. Of the important branches of the RCA, it should be noted the branch of the cone of the pulmonary trunk, the branch of the sinus node, the branch of the right edge of the heart, the posterior interventricular branch.

The branch of the cone of the pulmonary trunk often anastomoses with the cone branch, which departs from the anterior interventricular branch, forming the annulus of Viessen. However, in approximately half of the cases (Schlesinger M. et al., 1949), the artery of the cone of the pulmonary trunk departs from the aorta on its own.

The branch of the sinus node in 60–86% of cases (Ariev M.Ya., 1949) departs from the RCA, however, there is evidence that in 45% of cases (James T., 1961) it can depart from the envelope branch of the LCA and even from the LCA itself . The branch of the sinus node is located along the wall of the pancreas and reaches the confluence of the superior vena cava into the right atrium.

At the sharp edge of the heart, the RCA gives off a fairly constant branch - the branch of the right edge, which runs along the sharp edge to the apex of the heart. Approximately at this level, a branch departs to the right atrium, which supplies blood to the anterior and side surface right atrium.

At the site of transition of the RCA to the posterior interventricular artery, a branch of the AV node departs from it, which supplies blood to this node. From the posterior interventricular branch, branches to the pancreas depart perpendicularly, as well as short branches to the posterior third of the interventricular septum, which anastomose with similar branches extending from the anterior interventricular artery of the LCA.

Thus, the RCA supplies blood to the anterior and posterior walls of the pancreas, partially to the posterior wall of the left ventricle, the right atrium, the upper half of the interatrial septum, the sinus and AV nodes, as well as the posterior part of the interventricular septum and the posterior papillary muscle.

V.V. Bratus, A.S. Gavrish "Structure and functions of the cardiovascular system"

Anatomy of the coronary circulation highly variable. Features of the coronary circulation of each person are unique, like fingerprints, therefore, each myocardial infarction is "individual". The depth and prevalence of a heart attack depend on the interweaving of many factors, in particular, on the congenital anatomical features of the coronary bed, the degree of development of collaterals, the severity of atherosclerotic lesions, the presence of "prodromes" in the form of angina, which first occurred during the days preceding the infarction (ischemic "training" of the myocardium), spontaneous or iatrogenic reperfusion, etc.

As is known, heart receives blood from two coronary (coronary) arteries: the right coronary artery and the left coronary artery [respectively a. coronaria sinistra and left coronary artery (LCA)]. These are the first branches of the aorta that depart from its right and left sinuses.

Barrel LKA[in English - left main coronary artery (LMCA)] departs from the upper part of the left aortic sinus and goes behind the pulmonary trunk. The diameter of the LCA trunk is from 3 to 6 mm, the length is up to 10 mm. Usually the trunk of the LCA is divided into two branches: the anterior interventricular branch (AMV) and the circumflex (Fig. 4.11). In 1/3 of cases, the LCA trunk is divided not into two, but into three vessels: the anterior interventricular, circumflex, and median (intermediate) branches. In this case, the median branch (ramus medianus) is located between the anterior interventricular and envelope branches of the LCA.
This vessel- analogue of the first diagonal branch (see below) and usually supplies the anterolateral sections of the left ventricle.

Anterior interventricular (descending) branch of the LCA follows the anterior interventricular sulcus (sulcus interventricularis anterior) towards the apex of the heart. In English literature, this vessel is called the left anterior descending artery: left anterior descending artery (LAD). We will adhere to the more accurate anatomically (F. H. Netter, 1987) and the term "anterior interventricular branch" accepted in the domestic literature (O. V. Fedotov et al., 1985; S. S. Mikhailov, 1987). At the same time, when describing coronarograms, it is better to use the term "anterior interventricular artery" to simplify the name of its branches.

main branches latest- septal (penetrating, septal) and diagonal. The septal branches depart from the PMA at a right angle and deepen into the thickness of the interventricular septum, where they anastomose with similar branches extending from below the posterior interventricular branch of the right coronary artery (RCA). These branches may differ in number, length, direction. Sometimes there is a large first septal branch (going either vertically or horizontally - as if parallel to the PMA), from which branches extend to the septum. Note that of all areas of the heart, the interventricular septum of the heart has the thickest vascular network. The diagonal branches of the PMA run along the anterolateral surface of the heart, which they supply with blood. There are from one to three such branches.

In 3/4 cases of PMV does not end in the region of the apex, but, bending around the latter on the right, wraps itself on the diaphragmatic surface of the posterior wall of the left ventricle, supplying both the apex and partially the posterior diaphragmatic sections of the left ventricle, respectively. This explains the appearance of the Q wave on the ECG in lead aVF in a patient with extensive anterior infarction. In other cases, ending at the level or not reaching the apex of the heart, PMA does not play a significant role in its blood supply. Then the apex receives blood from the posterior interventricular branch of the RCA.

proximal area front The interventricular branch (PMV) of the LCA is called the segment from the mouth of this branch to the origin of the first septal (penetrating, septal) branch or to the origin of the first diagonal branch (less stringent criterion). Accordingly, the middle section is a segment of the PMA from the end of the proximal section to the departure of the second or third diagonal branch. Next is the distal section of the PMA. When there is only one diagonal branch, the boundaries of the middle and distal sections are approximately defined.

Educational video of the blood supply of the heart (anatomy of arteries and veins)

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The arteries of the heart depart from the aortic bulb, and, like a crown, surround the heart, in connection with which they are called coronary arteries.

Right coronary artery goes to the right under the ear of the right atrium, lies in the coronary sulcus and goes around the right surface of the heart. The branches of the right coronary artery supply the walls of the right ventricle and atrium, the back of the interventricular septum, the papillary muscles of the left ventricle, the sinoatrial and atrioventricular nodes of the cardiac conduction system.

Left coronary artery thicker than the right one and is located between the beginning of the pulmonary trunk and the auricle of the left atrium. The branches of the left coronary artery supply the walls of the left ventricle, papillary muscles, most of the interventricular septum, the anterior wall of the right ventricle, and the walls of the left atrium.

The branches of the right and left coronary arteries form two arterial rings around the heart: transverse and longitudinal. They provide blood supply to all layers of the walls of the heart.

There are several types of blood supply to the heart:

right coronary type - most parts of the heart are supplied with blood by the branches of the right coronary artery;
left coronary type - most of the heart receives blood from the branches of the left coronary artery;
uniform type - blood is evenly distributed through the arteries;
middle right type - transitional type of blood supply;
middle left type - transitional type of blood supply.

It is believed that among all types of blood supply, the middle right type is predominant.

Veins of the heart more numerous than arteries. Most of the major veins of the heart are collected in coronary sinus- one common wide venous vessel. The coronary sinus is located in the coronary groove on the posterior surface of the heart and opens into the right atrium. The tributaries of the coronary sinus are 5 veins:

large vein of the heart;
middle vein of the heart;
small vein of the heart;
posterior vein of the left ventricle;
oblique vein of the left atrium.

In addition to these five veins that flow into the coronary sinus, the heart has veins that open directly into the right atrium: anterior veins of the heart, and smallest veins of the heart.

Vegetative innervation of the heart.

Parasympathetic innervation of the heart

Preganglionic parasympathetic cardiac fibers are part of the branches extending from the vagus nerves on both sides in the neck. Fibers from the right vagus nerve predominantly innervate the right atrium and especially abundantly the sinoatrial node. The fibers from the left vagus nerve are mainly suitable for the atrioventricular node. As a result, the right vagus nerve mainly affects the heart rate, and the left one on atrioventricular conduction. The parasympathetic innervation of the ventricles is weakly expressed and exerts its influence indirectly, due to the inhibition of sympathetic effects.

Sympathetic innervation of the heart

Sympathetic nerves, in contrast to the vagus, are almost evenly distributed throughout all parts of the heart. Preganglionic sympathetic cardiac fibers originate in the lateral horns of the upper thoracic segments. spinal cord. In the cervical and upper thoracic ganglia of the sympathetic trunk, in particular in the stellate ganglion, these fibers switch to postganglionic neurons. The processes of the latter approach the heart as part of several cardiac nerves.

In most mammals, including humans, ventricular activity is controlled predominantly by sympathetic nerves. As for the atria and, especially, the sinoatrial node, they are under constant antagonistic influences from the vagus and sympathetic nerves.

Afferent nerves of the heart

The heart is innervated not only by efferent, but also by a large number of afferent fibers that go as part of the vagus and sympathetic nerves. Most of the afferent pathways belonging to the vagus nerves are myelinated fibers with sensory endings in the atria and left ventricle. When recording the activity of single atrial fibers, two types of mechanoreceptors were identified: B receptors that respond to passive stretch, and A receptors that respond to active tension.

Along with these myelinated fibers from specialized receptors, there is another large group of sensory nerves extending from the free endings of the dense subendocardial plexus of amyelinous fibers. This group of afferent pathways is part of the sympathetic nerves. It is believed that these fibers are responsible for the sharp pains with segmental irradiation observed during coronary disease heart (angina pectoris and myocardial infarction).

Development of the heart. Anomalies of the position and structure of the heart.

Development of the heart

The complex and peculiar structure of the heart, which corresponds to its role as a biological engine, develops in the embryonic period. In the embryo, the heart goes through stages when its structure is similar to the two-chambered heart of fish and the incompletely blocked heart of reptiles. The rudiment of the heart appears during the period of the neural tube in an embryo of 2.5 weeks, having a length of only 1.5 mm. It is formed from the cardiogenic mesenchyme ventrally from the head end of the foregut in the form of paired longitudinal cell strands, in which thin endothelial tubes are formed. In the middle of the 3rd week, in an embryo 2.5 mm long, both tubes merge with each other, forming a simple tubular heart. At this stage, the rudiment of the heart consists of two layers. The inner, thinner layer represents the primary endocardium. Outside is a thicker layer, consisting of the primary myocardium and epicardium. At the same time, there is an expansion of the pericardial cavity, which surrounds the heart. At the end of the 3rd week, the heart begins to contract.

Due to its rapid growth, the heart tube begins to bend to the right, forming a loop, and then takes S-shape. This stage is called the sigmoid heart. At the 4th week, in an embryo 5 mm long, several parts can be distinguished in the heart. The primary atrium receives blood from the veins converging to the heart. At the confluence of the veins, an expansion is formed, called the venous sinus. From the atrium, through a relatively narrow atrioventricular canal, blood enters the primary ventricle. The ventricle continues into the bulb of the heart, followed by the truncus arteriosus. In places where the ventricle passes into the bulb and the bulb into the arterial trunk, as well as on the sides of the atrioventricular canal, there are endocardial tubercles, from which the heart valves develop. In its structure, the embryonic heart is similar to the two-chambered heart of an adult fish, the function of which is to supply venous blood to the gills.

During the 5th and 6th weeks there are significant changes in the relative position of the heart. Its venous end moves cranially and dorsally, while the ventricle and bulb move caudally and ventrally. Coronal and interventricular grooves appear on the surface of the heart, and it acquires in general terms definitive external form. In the same period, internal transformations begin, which lead to the formation of a four-chambered heart, characteristic of higher vertebrates. Partitions and valves develop in the heart. Atrial division begins in an embryo 6 mm long. In the middle of its posterior wall, a primary septum appears, it reaches the atrioventricular canal and merges with the endocardial tubercles, which by this time increase and divide the canal into the right and left parts. The primary septum is not complete; first, the primary and then the secondary interatrial openings are formed in it. Later, a secondary septum is formed, in which there is an oval opening. Through the foramen ovale, blood passes from the right atrium to the left. The hole is covered by the edge of the primary septum, which forms a damper that prevents the reverse flow of blood. Complete fusion of the primary and secondary septa occurs at the end of the intrauterine period.

At the 7th and 8th weeks of embryonic development, a partial reduction of the venous sinus occurs. Its transverse part is transformed into the coronary sinus, the left horn is reduced to a small vessel - the oblique vein of the left atrium, and the right horn forms part of the wall of the right atrium between the confluence of the superior and inferior vena cava. The common pulmonary vein and the trunks of the right and left pulmonary veins, as a result of which two veins from each lung open into the atrium.

The bulb of the heart in the embryo of 5 weeks merges with the ventricle, forming an arterial cone belonging to the right ventricle. The arterial trunk is divided by the spiral septum developing in it into the pulmonary trunk and the aorta. From below, the spiral septum continues towards the interventricular septum in such a way that the pulmonary trunk opens into the right, and the beginning of the aorta into the left ventricle. The endocardial tubercles located in the bulb of the heart take part in the formation of the spiral septum; at their expense, the valves of the aorta and pulmonary trunk are also formed.

The interventricular septum begins to develop on the 4th week, its growth occurs from the bottom up, but until the 7th week the septum remains incomplete. In its upper part is the interventricular opening. The latter is closed by growing endocardial tubercles, in this place the membranous part of the septum is formed. The atrioventricular valves form from the endocardial tubercles.

As the chambers of the heart separate and valves form, the tissues that make up the wall of the heart differentiate. The atrioventricular conduction system is secreted in the myocardium. The pericardial cavity is separated from the general body cavity. The heart moves from the neck to chest cavity. The heart of the embryo and fetus has a relatively big sizes, since it provides not only the movement of blood through the vessels of the body of the embryo, but also the placental circulation.

Throughout the prenatal period, a message is maintained between the right and left halves of the heart through the oval hole. Blood entering the right atrium through the inferior vena cava is directed by the valves of this vein and the coronary sinus to the foramen ovale and through it into the left atrium. From superior vena cava blood is coming into the right ventricle and is expelled into the pulmonary trunk. The small circle of blood circulation in the fetus does not function, since the narrow pulmonary vessels provide great resistance to blood flow. Only 5-10% of the blood entering the pulmonary trunk passes through the lungs of the fetus. The rest of the blood is discharged through the ductus arteriosus into the aorta and enters big circle circulation bypassing the lungs. Thanks to the foramen ovale and ductus arteriosus, the balance of blood flow through the right and left halves of the heart is maintained.

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Widespread use of selective coronary angiography and surgical interventions on the coronary arteries of the heart in last years made it possible to study anatomical features of the coronary circulation of a living person, to develop a functional anatomy of the arteries of the heart in relation to revascularization operations in patients with coronary heart disease.

Interventions on the coronary arteries for diagnostic and therapeutic purposes place increased demands on the study of vessels on different levels taking into account their variants, developmental anomalies, caliber, angles of departure, possible collateral connections, as well as their projections and relationships with surrounding formations.

When systematizing these data, we paid special attention to information from the surgical anatomy of the coronary arteries, based on the principle topographic anatomy in relation to the operation plan with the division of the coronary arteries of the heart into segments.

The right and left coronary arteries were conditionally divided into three and seven segments, respectively (Fig. 51).

Three segments were distinguished in the right coronary artery: I - a segment of the artery from the mouth to the outlet of the branch - the artery of the sharp edge of the heart (length from 2 to 3.5 cm); II - section of the artery from the branch of the sharp edge of the heart to the discharge of the posterior interventricular branch of the right coronary artery (length 2.2-3.8 cm); III - posterior interventricular branch of the right coronary artery.

The initial section of the left coronary artery from the mouth to the place of division into the main branches is designated as segment I (length from 0.7 to 1.8 cm). The first 4 cm of the anterior interventricular branch of the left coronary artery is divided

Rice. 51. Segmental division of the coronary

heart arteries:

BUT- right coronary artery; B- left coronary artery

into two segments of 2 cm each - II and III segments. The distal portion of the anterior interventricular branch was segment IV. The circumflex branch of the left coronary artery to the point of origin of the branch of the blunt edge of the heart is the V segment (length 1.8-2.6 cm). The distal section of the circumflex branch of the left coronary artery was more often represented by the artery of the obtuse margin of the heart - segment VI. And, finally, the diagonal branch of the left coronary artery is the VII segment.

The use of segmental division of the coronary arteries, as our experience has shown, is advisable in a comparative study of the surgical anatomy of the coronary circulation according to selective coronary angiography and surgical interventions, to determine the localization and spread of the pathological process in the arteries of the heart, has practical value when choosing a method of surgical intervention in case of coronary heart disease.

Rice. 52. Right-wing type of coronary circulation. Well developed posterior interventricular branches

Beginning of the coronary arteries . Sinuses of the aorta, from which the coronary arteries depart, James (1961) proposes to call the right and left coronary sinus. The orifices of the coronary arteries are located in the bulb of the ascending aorta at the level of the free edges of the aortic semilunar valves or 2-3 cm above or below them (V. V. Kovanov and T. I. Anikina, 1974).

The topography of the sections of the coronary arteries, as A. S. Zolotukhin (1974) points out, is different and depends on the structure of the heart and chest. According to M. A. Tikhomirov (1899), the orifices of the coronary arteries in the aortic sinuses can be located below the free edge of the valves "abnormally low", so that the semilunar valves pressed against the wall of the aorta close the orifices, either at the level of the free edge of the valves, or above them, by wall of the ascending aorta.

The level of the location of the mouths is of practical importance. With a high location at the time of left ventricular systole, the orifice is

under the blow of a stream of blood, not being covered by the edge of the semilunar valve. According to A. V. Smolyannikov and T. A. Naddachina (1964), this may be one of the reasons for the development of coronary sclerosis.

The right coronary artery in most patients has a main type of division and plays an important role in the vascularization of the heart, especially its posterior diaphragmatic surface. In 25% of patients in the blood supply to the myocardium, we revealed the predominance of the right coronary artery (Fig. 52). N. A. Javakhshivili and M. G. Komakhidze (1963) describe the beginning of the right coronary artery in the region of the anterior right sinus of the aorta, indicating that its high discharge is rarely observed. The artery enters the coronary sulcus, located behind the base of the pulmonary artery and under the auricle of the right atrium. The section of the artery from the aorta to the sharp edge of the heart (segment I of the artery) is adjacent to the wall of the heart and is completely covered by subepicardial fat. The diameter of segment I of the right coronary artery ranges from 2.1 to 7 mm. Along the artery trunk on the anterior surface of the heart in the coronary sulcus, epicardial folds are formed, filled with adipose tissue. Abundantly developed adipose tissue noted along the artery from the sharp edge of the heart. The atherosclerotically altered trunk of the artery along this length is well palpated in the form of a cord. Detection and isolation of segment I of the right coronary artery on the anterior surface of the heart is usually not difficult.

The first branch of the right coronary artery - the artery of the arterial cone, or the fatty artery - leaves directly at the beginning of the coronary sulcus, continuing down to the right at the arterial cone, giving branches to the cone and the wall of the pulmonary trunk. In 25.6% of patients, we observed its common beginning with the right coronary artery, its mouth was located at the mouth of the right coronary artery. In 18.9% of patients, the mouth of the conus artery was located next to the mouth of the coronary artery, located behind the latter. In these cases, the vessel originated directly from the ascending aorta and was only slightly inferior in size to the trunk of the right coronary artery.

Muscular branches depart from the I segment of the right coronary artery to the right ventricle of the heart. Vessels in the amount of 2-3 are located closer to the epicardium in connective tissue couplings on the layer of adipose tissue covering the epicardium.

The other most significant and permanent branch of the right coronary artery is the right marginal artery (a branch of the sharp edge of the heart). The artery of the acute edge of the heart, a constant branch of the right coronary artery, departs in the region of the acute edge of the heart and descends along the lateral surface of the heart to its apex. It supplies blood to the anterior-lateral wall of the right ventricle, and sometimes to the diaphragmatic part of it. In some patients, the diameter of the lumen of the artery was about 3 mm, but more often it was 1 mm or less.

Continuing along the coronary sulcus, the right coronary artery goes around the sharp edge of the heart, passes to the posterior diaphragmatic surface of the heart and ends to the left of the posterior interventricular sulcus, not reaching the blunt edge of the heart (in 64% of patients).

The final branch of the right coronary artery - the posterior interventricular branch (III segment) - is located in the posterior interventricular groove, descending along it to the apex of the heart. V. V. Kovanov and T. I. Anikina (1974) distinguish three variants of its distribution: 1) in the upper part of the furrow of the same name; 2) throughout this groove to the top of the heart; 3) the posterior interventricular branch enters the anterior surface of the heart. According to our data, only in 14% of patients it reached

apex of the heart, anastomosing with the anterior interventricular branch of the left coronary artery.

From the posterior interventricular branch into the interventricular septum at right angles, from 4 to 6 branches depart, supplying blood to the conducting system of the heart.

With a right-sided type of coronary blood supply to the diaphragmatic surface of the heart, 2-3 muscle branches extend from the right coronary artery, running parallel to the posterior interventricular branch of the right coronary artery.

To access the II and III segments of the right coronary artery, it is necessary to lift the heart up and take it to the left. II segment of the artery is located superficially in the coronary sulcus; it can be easily and quickly found and selected. The posterior interventricular branch (III segment) is located deep in the interventricular groove and is covered by subepicardial fat. When performing operations on the II segment of the right coronary artery, it must be remembered that the wall of the right ventricle in this place is very thin. Therefore, it should be handled carefully to avoid perforation.

The left coronary artery, participating in the blood supply to most of the left ventricle, the interventricular septum, as well as the anterior surface of the right ventricle, dominates the blood supply to the heart in 20.8% of patients. Starting in the left sinus of Valsalva, it goes from the ascending aorta to the left and down the coronary sulcus of the heart. The initial section of the left coronary artery (I segment) before the bifurcation has a length of at least 8 mm and not more than 18 mm. Isolation of the main trunk of the left coronary artery is difficult, since it is hidden by the root of the pulmonary artery.

The short trunk of the left coronary artery, 3.5 to 7.5 mm in diameter, turns to the left between the pulmonary artery and the base of the left auricle of the heart and divides into the anterior interventricular and circumflex branches. (II, III, IV segments of the left coronary artery) is located in the anterior interventricular groove of the heart, along which it goes to the apex of the heart. It can end at the apex of the heart, but usually (according to our observations, in 80% of patients) it continues on the diaphragmatic surface of the heart, where it meets the terminal branches of the posterior interventricular branch of the right coronary artery and participates in the vascularization of the diaphragmatic surface of the heart. The diameter of segment II of the artery ranges from 2 to 4.5 mm.

It should be noted that a significant part of the anterior interventricular branch (segments II and III) lies deep, covered by subepicardial fat and muscle bridges. The isolation of the artery in this place requires great care because of the danger of possible damage to its muscular and, most importantly, septal branches leading to the interventricular septum. The distal part of the artery (IV segment) is usually located superficially, is clearly visible under a thin layer of subepicardial tissue and is easily distinguished.

From the II segment of the left coronary artery, from 2 to 4 septal branches extend deep into the myocardium, which are involved in the vascularization of the interventricular septum of the heart.

Throughout the anterior interventricular branch of the left coronary artery, 4-8 muscle branches depart to the myocardium of the left and right ventricles. The branches to the right ventricle are smaller in caliber than to the left, although they are the same in size as the muscular branches from the right coronary artery. Much more branches departs to the anterior-lateral wall of the left ventricle. In functional terms, the diagonal branches are especially important (there are 2 of them, sometimes 3), extending from the II and III segments of the left coronary artery.

When searching for and isolating the anterior interventricular branch, an important landmark is the large vein of the heart, which is located in the anterior interventricular groove to the right of the artery and is easily found under a thin layer of the epicardium.

The circumflex branch of the left coronary artery (V-VI segments) departs at a right angle to the main trunk of the left coronary artery, located in the left coronary sulcus, under the left auricle of the heart. Its permanent branch - the branch of the blunt edge of the heart - descends over a considerable distance at the left edge of the heart, somewhat backwards, and in 47.2% of patients reaches the apex of the heart.

After the branches branch off to the blunt edge of the heart and the posterior surface of the left ventricle, the circumflex branch of the left coronary artery in 20% of patients continues along the coronary sulcus or along the posterior wall of the left atrium in the form of a thin trunk and reaches the confluence of the inferior posterior vein.

The V segment of the artery is easily detected, which is located in the fatty membrane under the ear of the left atrium and is covered by a large vein of the heart. The latter sometimes has to be crossed to gain access to the trunk of the artery.

The distal envelope of the branch (VI segment) is usually located on the posterior surface of the heart and, if necessary, surgical intervention on it, the heart is lifted and taken to the left while pulling the left ear of the heart.

The diagonal branch of the left coronary artery (VII segment) goes along the anterior surface of the left ventricle down and to the right, then plunging into the myocardium. The diameter of its initial part is from 1 to 3 mm. With a diameter of less than 1 mm, the vessel is little expressed and is more often considered as one of the muscular branches of the anterior interventricular branch of the left coronary artery.

Anatomy of the coronary arteries

coronary arteries

From an anatomical point of view, the coronary artery system is divided into two parts - right and left. From a surgical standpoint, the coronary artery is divided into four parts: the left main coronary artery (trunk), the left anterior descending artery or anterior interventricular branch (LAD) and its branches, the left circumflex coronary artery (OC) and its branches, the right coronary artery (RCA) ) and its branches.

The large coronary arteries form an arterial ring and loop around the heart. The left circumflex and right coronary arteries are involved in the formation of the arterial ring, passing through the atrioventricular sulcus. The formation of the arterial loop of the heart involves the anterior descending artery from the system of the left coronary artery and the posterior descending artery from the system of the right coronary artery, or from the system of the left coronary artery - from the left circumflex artery with the left dominant type of blood supply. The arterial ring and loop are a functional device for the development of collateral circulation of the heart.

Right coronary artery

The right coronary artery (right coronary artery) departs from the right sinus of Valsalva and passes in the coronary (atrioventricular) groove. In 50% of cases, immediately at the place of origin, it gives off the first branch - the branch of the arterial cone (conus artery, conus branch, CB), which feeds the infundibulum of the right ventricle. Its second branch is the artery of the sinoatrial node (S-A node artery, SNA). leaving from the right coronary artery back at a right angle into the gap between the aorta and the wall of the right atrium, and then along its wall to the sinoatrial node. As a branch of the right coronary artery, this artery occurs in 59% of cases. In 38% of cases, the artery of the sinoatrial node is a branch of the left circumflex artery. And in 3% of cases there is a blood supply to the sino-atrial node from two arteries (both from the right and from the circumflex). In the anterior part of the coronary sulcus, in the region of the acute edge of the heart, the right marginal branch departs from the right coronary artery (acute marginal artery, acute marginal branch, AMB), more often from one to three, which in most cases reaches the apex of the heart. Then the artery turns back, lies in the back of the coronary sulcus and reaches the "cross" of the heart (the intersection of the posterior interventricular and atrioventricular sulcus of the heart).

With the so-called right type of blood supply to the heart, observed in 90% of people, the right coronary artery gives off the posterior descending artery (PDA), which runs along the posterior interventricular groove for a different distance, giving branches to the septum (anastomosing with similar branches from the anterior descending artery, the latter usually longer than the first), the right ventricle and branches to the left ventricle. After the posterior descending artery (PDA) originates, the RCA continues beyond the cross of the heart as the right posterior atrioventricular branch along the distal part of the left atrioventricular sulcus, terminating in one or more posterolateral branches (posterolateral branches) feeding the diaphragmatic surface of the left ventricle. . On the posterior surface of the heart, immediately below the bifurcation, at the point of transition of the right coronary artery into the posterior interventricular sulcus, an arterial branch originates from it, which, piercing the interventricular septum, goes to the atrioventricular node - the artery of the atrioventricular node (atrioventricular node artery, AVN).

Left coronary artery

The left coronary artery (left coronary artery) originates from the left posterior surface of the aortic bulb and exits to left side coronal sulcus. Its main trunk (left main coronary artery, LMCA) is usually short (0-10 mm, diameter varies from 3 to 6 mm) and is divided into anterior interventricular (left anterior descending artery, LAD) and envelope (left circumflex artery, LCx) branches . In 30-37% of cases, the third branch departs here - the intermediate artery (ramus intermedius, RI), which crosses obliquely the wall of the left ventricle. LAD and OB form an angle between them, which varies from 30 to 180°.

Anterior interventricular branch

The anterior interventricular branch is located in the anterior interventricular sulcus and goes to the apex, giving off the anterior ventricular branches (diagonal, diagonal artery, D) and the anterior septal (septal branch)) along the way. In 90% of cases, one to three diagonal branches are determined. Septal branches depart from the anterior interventricular artery at an angle of approximately 90 degrees, perforate the interventricular septum, feeding it. The anterior interventricular branch sometimes enters the thickness of the myocardium and again lies in the groove and often reaches the apex of the heart along it, where in about 78% of people it turns back to the diaphragmatic surface of the heart and for a short distance (10-15 mm) rises up along the posterior interventricular groove. In such cases, it forms a posterior ascending branch. Here it often anastomoses with the terminal branches of the posterior interventricular artery, a branch of the right coronary artery.

circumflex artery

Anatomy of the coronary arteries.

Professor, Dr. med. Sciences Yu.P. Ostrovsky

On the this moment There are many variants of classifications of coronary arteries adopted in different countries and centers of the world. But, in our opinion, there are certain terminological differences between them, which creates difficulties in the interpretation of coronary angiography data by specialists of different profiles.

We have analyzed the literature on the anatomy and classification of the coronary arteries. Data from literary sources are compared with their own. A working classification of the coronary arteries has been developed in accordance with the nomenclature adopted in the English literature.

coronary arteries

The large coronary arteries form an arterial ring and loop around the heart. The left circumflex and right coronary arteries are involved in the formation of the arterial ring, passing through the atrioventricular sulcus. The anterior descending artery from the system of the left coronary artery and the posterior descending artery from the system of the right coronary artery, or from the system of the left coronary artery - from the left circumflex artery with the left dominant type of blood supply participate in the formation of the arterial loop of the heart. The arterial ring and loop are a functional device for the development of collateral circulation of the heart.

Right coronary artery

Right coronary artery(right coronary artery) departs from the right sinus of Valsalva and passes in the coronary (atrioventricular) groove. In 50% of cases, immediately at the place of origin, it gives off the first branch - the branch of the arterial cone (conus artery, conus branch, CB), which feeds the infundibulum of the right ventricle. Its second branch is the artery of the sinoatrial node (S-A node artery, SNA). leaving the right coronary artery back at a right angle into the gap between the aorta and the wall of the right atrium, and then along its wall to the sinoatrial node. As a branch of the right coronary artery, this artery occurs in 59% of cases. In 38% of cases, the artery of the sinoatrial node is a branch of the left circumflex artery. And in 3% of cases there is a blood supply to the sino-atrial node from two arteries (both from the right and from the circumflex). In the anterior part of the coronary sulcus, in the region of the acute edge of the heart, the right marginal branch departs from the right coronary artery (acute marginal artery, acute marginal branch, AMB), more often from one to three, which in most cases reaches the apex of the heart. Then the artery turns back, lies in the back of the coronary sulcus and reaches the "cross" of the heart (the intersection of the posterior interventricular and atrioventricular sulcus of the heart).

The branches of the right coronary artery vascularize: the right atrium, part of the anterior, the entire posterior wall of the right ventricle, a small portion of the posterior wall of the left ventricle, the interatrial septum, the posterior third of the interventricular septum, the papillary muscles of the right ventricle and the posterior papillary muscle of the left ventricle.

Left coronary artery

Left coronary artery(left coronary artery) starts from the left posterior surface of the aortic bulb and goes to the left side of the coronary sulcus. Its main trunk (left main coronary artery, LMCA) is usually short (0-10 mm, diameter varies from 3 to 6 mm) and is divided into anterior interventricular (left anterior descending artery, LAD) and envelope (left circumflex artery, LCx) branches . In 30-37% of cases, the third branch departs here - the intermediate artery (ramus intermedius, RI), which crosses obliquely the wall of the left ventricle. LAD and OB form an angle between them, which varies from 30 to 180°.

Anterior interventricular branch

The circumflex branch of the left coronary artery is located in the left part of the coronary sulcus and in 38% of cases gives the first branch to the artery of the sinoatrial node, and then the artery of the obtuse marginal artery (obtuse marginal artery, obtuse marginal branch, OMB), usually from one to three. These fundamentally important arteries feed the free wall of the left ventricle. In the case when there is a right type of blood supply, the circumflex branch gradually becomes thinner, giving branches to the left ventricle. With a relatively rare left type (10% of cases), it reaches the level of the posterior interventricular sulcus and forms the posterior interventricular branch. With an even rarer, so-called mixed type there are two posterior ventricular branches of the right coronary and circumflex arteries. The left circumflex artery forms important atrial branches, which include the left atrial circumflex artery (LAC) and the large anastomosing auricular artery.

The branches of the left coronary artery vascularize the left atrium, the entire anterior and most of the posterior wall of the left ventricle, part of the anterior wall of the right ventricle, the anterior 2/3 of the interventricular septum, and the anterior papillary muscle of the left ventricle.

Types of blood supply to the heart

The type of blood supply to the heart is understood as the predominant distribution of the right and left coronary arteries on the posterior surface of the heart.

The anatomical criterion for assessing the predominant type of distribution of the coronary arteries is the avascular zone on the posterior surface of the heart, formed by the intersection of the coronary and interventricular sulci, - crux. Depending on which of the arteries - right or left - reaches this zone, the predominant right or left type of blood supply to the heart is distinguished. The artery reaching this zone always gives off a posterior interventricular branch, which runs along the posterior interventricular sulcus towards the apex of the heart and supplies blood to the posterior part of the interventricular septum. Another anatomical feature is described to determine the predominant type of blood supply. It is noted that the branch to the atrioventricular node always departs from the predominant artery, i.e. from the artery, which is of the greatest importance in the supply of blood to the posterior surface of the heart.

Thus, with predominant right type of blood supply to the heart The right coronary artery supplies the right atrium, the right ventricle, the posterior part of the interventricular septum, and the posterior surface of the left ventricle. The right coronary artery is represented by a large trunk, and the left circumflex artery is poorly expressed.

With predominant left type of blood supply to the heart the right coronary artery is narrow and terminates in short branches on the diaphragmatic surface of the right ventricle, and the posterior surface of the left ventricle, the posterior part of the interventricular septum, the atrioventricular node and most of the posterior surface of the ventricle receive blood from the well-defined large left circumflex artery.

In addition, there are also balanced type of blood supply. in which the right and left coronary arteries contribute approximately equally to the blood supply to the posterior surface of the heart.

The concept of "primary type of blood supply to the heart", although conditional, is based on the anatomical structure and distribution of the coronary arteries in the heart. Since the mass of the left ventricle is much larger than the right one, and the left coronary artery always supplies blood to most of the left ventricle, 2/3 of the interventricular septum and the wall of the right ventricle, it is clear that the left coronary artery is predominant in all normal hearts. Thus, for any of the types coronary blood supply predominant in the physiological sense is the left coronary artery.

Nevertheless, the concept of "predominant type of blood supply to the heart" is valid, it is used to assess anatomical findings during coronary angiography and is of great practical importance in determining indications for myocardial revascularization.

For topical indication of lesions, it is proposed to divide the coronary bed into segments.

Dotted lines in this scheme highlight the segments of the coronary arteries.

So in the left coronary artery in the anterior interventricular branch it is divided into three segments:

1. proximal - from the place of origin of the LAD from the trunk to the first septal perforator or 1DV.

2. medium - from 1DV to 2DV.

3. distal - after the discharge of 2DV.

In circumflex artery It is also customary to distinguish three segments:

1. proximal - from the mouth of the OB to 1 VTK.

3. distal - after the departure of 3 VTK.

Right coronary artery divided into the following main segments:

1. proximal - from the mouth to 1 wok

2. medium - from 1 wok to the sharp edge of the heart

3. distal - up to the RCA bifurcation to the posterior descending and posterolateral arteries.

Coronary angiography

Coronary angiography(coronary angiography) is an X-ray visualization of the coronary vessels after the introduction of a radiopaque substance. The x-ray image is immediately recorded on 35 mm film or digital media for further analysis.

Currently, coronary angiography is the "gold standard" for determining the presence or absence of stenosis in coronary disease.

The purpose of coronary angiography is to determine the coronary anatomy and the degree of narrowing of the lumen of the coronary arteries. Information obtained during the procedure includes determining the location, extent, diameter and contours of the coronary arteries, the presence and degree of coronary obstruction, characterization of the nature of the obstruction (including the presence of an atherosclerotic plaque, thrombus, dissection, spasm or myocardial bridge).

The data obtained determine the further tactics of the patient's treatment: coronary bypass grafting, intervention, drug therapy.

To conduct high-quality angiography, selective catheterization of the right and left coronary arteries is necessary, for which a large number of diagnostic catheters of various modifications have been created.

The study is performed under local anesthesia and NLA through arterial access. The following arterial accesses are generally recognized: femoral arteries, brachial arteries, radial arteries. Transradial access to recent times won a strong position and became widely used due to its low trauma and convenience.

After puncture of the artery, diagnostic catheters are inserted through the introducer, followed by selective catheterization of the coronary vessels. The contrast agent is dosed using an automatic injector. Shooting is performed in standard projections, the catheters and intraduser are removed, and a compression bandage is applied.

Basic angiographic projections

During the procedure, the goal is to obtain the most complete information about the anatomy of the coronary arteries, their morphological characteristics, the presence of changes in the vessels with an accurate determination of the location and nature of the lesions.

To achieve this goal, coronary angiography of the right and left coronary arteries is performed in standard projections. (Their description is given below). If it is necessary to conduct a more detailed study, shooting is carried out in special projections. This or that projection is optimal for the analysis of a certain section of the coronary bed and allows you to most accurately identify the features of the morphology and the presence of pathology in this segment.

Below are the main angiographic projections with an indication of the arteries for visualization of which these projections are optimal.

For left coronary artery There are the following standard projections.

1. Right anterior oblique with caudal angulation.

RAO 30, Caudal 25.

2. Right anterior oblique view with cranial angulation.

RAO 30, cranial 20

LAD, its septal and diagonal branches

3. Left anterior oblique with cranial angulation.

LAO 60, cranial 20.

Orifice and distal segment of the LCA trunk, middle and distal segment of the LAD, septal and diagonal branches, proximal segment of the OB, VTK.