Coronary artery what. Coronary arteries

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, and therefore are called coronary arteries. The right coronary artery begins at the level of the right aortic sinus, and the left coronary artery begins 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 allow blood to pass to the heart. When the ventricles relax (diastole), the sinuses fill with blood, closing its path from the aorta back to the left ventricle, and at the same time opening the access of blood to the vessels of the heart.

Right coronary artery

It goes to the right under the appendage of the right atrium, lies in the coronary sulcus, goes around the right pulmonary surface of the heart, then follows along its back surface to the left, where its end anastomoses 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 same groove of the heart towards its apex. The branches of the right coronary artery supply blood to the wall of the right ventricle and atrium, the posterior part interventricular septum, papillary muscles of the right ventricle, posterior papillary muscle of the left ventricle, sinoatrial and atrioventricular nodes of the conduction system of the heart.

Left coronary artery

Slightly thicker than the right one. 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, bends around the heart on the left, located in its coronary sulcus, where on the posterior surface of the organ it anastomoses with the right coronary artery. The anterior interventricular branch follows the same groove of the heart towards its apex. In the area 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 groove, and a longitudinal one, the vessels of which are located in the anterior and posterior interventricular grooves.

The 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 highest, microvessels anastomosing among themselves repeat the course of the bundles muscle fibers its layers.

There are different options for the distribution of branches of the coronary arteries, which are called types of blood supply to the heart. The main ones are the following: 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 middle, 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.

Variations and anomalies in the position and branching of the coronary arteries are possible. They manifest themselves in changes in the origin and number of coronary arteries. Thus, the latter can extend from the aorta directly above the semilunar valves or significantly 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 (accessory) arteries go to the heart (especially to the pericardium). These may be the mediastinal-pericardial branches (upper, middle and lower) of the internal thoracic artery, branches of the pericardial-phragmatic artery, branches extending from the concave surface of the aortic arches, etc.

The heart muscle, unlike other muscles of the body that are often at rest, works continuously. Therefore, it has a very high oxygen demand and nutrients ah, which means it needs a reliable and continuous supply of blood. The coronary arteries are designed to provide a continuous supply of blood necessary for the myocardium to function properly.

Myocardial vasculature

Due to the impermeability of the inner walls of the heart (endocardium) and the large thickness of the myocardium, the heart is not deprived of the opportunity to use the blood contained in its own chambers to obtain oxygen and nutrition. Therefore, it has its own blood supply system, consisting of coronary vessels hearts. Two main coronary (coronary) arteries are responsible for the general distribution of blood:

• left (LCA or LCA);
• and right (PCA or RCA).

Both of them begin their journey from the corresponding sinuses at the base of the aorta, located behind the valves aortic valve as shown in the diagram coronary arteries. When the heart is relaxed, blood flows into its pockets and then enters the coronary arteries. Since the LCA and RCA lie on the surface of the heart, they are called epicardial, their branches running deep in the myocardium are called subepicardial. Most people have two coronary arteries, but about 4% also have a third, called the posterior (it is not shown in the diagram of the arteries of the heart).

The main trunk of the LCA has a lumen diameter, often exceeding 4.5 millimeters, and is one of the shortest and most important vessels of the body. It typically measures 1 to 2 cm in length, but may be as little as 2 mm in length before the division point. The left coronary artery divides into two branches:

• anterior descending or interventricular (LAD);
• envelope (OB).

The left anterior descending (anterior interventricular branch) usually begins as a continuation of the LMCA. Its size, length and extent are key factors in the balance of blood supply to the IVS (interventricular septum), LV (left ventricle), and most of both the left and right atria. Passing along the longitudinal cardiac groove, it goes to the apex of the heart (in some cases it continues beyond it to the posterior surface). The lateral branches of the LAD lie on the anterior surface of the LV, feeding its walls.

The bed of the OB, usually diverted from the LCA at a right angle, passing along the transverse groove, reaches the edge of the heart, goes around it, passes to the posterior wall of the LV and, in the form of the posterior descending artery, reaches the apex. One of the main branches of the OB is the branches of the obtuse margin (BMA), which supply the lateral wall of the LV.

The lumen (RCA) is about 2.5 mm or more. The anatomical structure of the RCA is individual and is decisive for the types of blood supply to the myocardium. The most important role is nutrition of the areas of the heart responsible for regulating heart rhythm.

Types of blood supply to the heart

Blood flow to the anterior and lateral surfaces of the myocardium is quite stable and is not subject to individual changes. Depending on where the coronary arteries and their branches are located in relation to the posterior part or surface of the myocardial diaphragm , there are three types of blood supply to the heart:

• Average. Consists of well-developed LAD, OB and RCA. The blood supply vessels entirely to the LV and from two-thirds to half of the IVS are branches of the LMCA. The pancreas and the rest of the IVS receive nutrition from the RCA. This is the most common type.
• Left. In this case, blood flow in the LV, the entire IVS and part of the posterior wall of the RV is carried out by the LCA network.
• Right. Isolated when the RV and posterior wall of the LV are supplied by the RCA.

These structural changes dynamic, they can only be accurately determined using coronary angiography. Exists important feature, characteristic of cardiac circulation, which consists in the presence of collaterals. This is the name given to alternative routes formed between the main vessels that can be activated at the moment when, for some reason, the working one is blocked in order to take over the functions of the one that has become unusable. The collateral network is most developed in elderly people suffering from coronary pathologies.

That is why in critical situations associated with blockage of the main myocardial vessels, young people are at greatest risk.

Disorders of the coronary arteries

Coronary arteries with abnormal structure are not uncommon. People do not have complete identity in the structure of blood circulation either with the standards of anatomy or with each other. Differences arise for many reasons. They can be divided into two groups:

• hereditary;
• purchased.

The former may be the result of abnormal variability, while the latter include the consequences of injuries, operations, inflammation and other diseases. The range of consequences from violations can be enormous: from asymptomatic to life-threatening. Anatomical changes in the coronary vessels include their position, direction, number, size and length. If congenital abnormalities are significant, they make themselves felt even in early age and are subject to treatment by a pediatric cardiologist.

But more often such changes are discovered by chance or against the background of another disease. Blockage or rupture of one of the coronary vessels leads to consequences of poor circulation proportional to the size of the damaged vessel. Normal operation main vessels of the myocardium and problems in their functioning are always reflected in typical clinical symptoms and ECG recordings.

Problems with blood supply to the myocardium make themselves felt when physical or emotional stress is exceeded. This is especially important to remember because some coronary anomalies can cause sudden cardiac arrest in the absence of underlying medical conditions.

Cardiac ischemia

CAD occurs when the arteries that supply blood to the heart muscle become fragile and narrowed due to deposits in the walls. It causes oxygen starvation myocardium. In the 21st century, IHD is the most common type of heart disease and main reason death in many countries. The main signs and consequences of a reduction in coronary blood flow:

If the reduction or absence of blood flow in the coronary vessels occurs due to stenotic lesions of the vessel, then blood supply can be restored using:

If the lack of blood flow is caused by blood clots (thrombosis), then medications that dissolve the clots are used. Aspirin and antiplatelet drugs are used to prevent recurrence of thrombosis.

Blood, thanks to the “internal motor” - the heart, circulates throughout the body, saturating every cell with nutrients and oxygen. How does the heart itself receive nutrition? Where does it get its reserves and strength for work? And do you know about the so-called third circle of blood circulation or heart? To better understand the anatomy of the vessels supplying the heart, let's look at the main anatomical structures that are usually identified in central authority of cardio-vascular system.

1 External structure of the human “motor”

First-year students of medical colleges and medical universities memorize by heart, and even in Latin, that the heart has an apex, a base, and two surfaces: the anterior superior and inferior, separated by edges. The cardiac grooves can be seen with the naked eye by looking at its surface. There are three of them:

1. coronal sulcus,
2. Anterior interventricular
3. Posterior interventricular.

The atria are visually separated from the ventricles by the coronary groove, and the border between the two lower chambers along the anterior surface is approximately the anterior interventricular groove, and along the rear surface the interventricular posterior groove. The interventricular grooves join at the apex slightly to the right. These grooves were formed due to the vessels running in them. In the coronary groove, which separates the cardiac chambers, there is the right coronary artery, the sinus veins, and in the anterior interventricular groove, which separates the ventricles, there is a large vein and an anterior interventricular branch.

The posterior interventricular groove is the receptacle for the interventricular branch of the right coronary artery, the middle cardiac vein. From the abundance of numerous medical terminology your head can go spinning: grooves, arteries, veins, branches... Of course, because we are analyzing the structure and blood supply of the most important human organ - the heart. If it were simpler, would it be able to perform such complex and responsible work? Therefore, let’s not give up halfway, and analyze in detail the anatomy of the heart vessels.

2 3rd or cardiac circle of blood circulation

Every adult knows that there are 2 circles of blood circulation in the body: large and small. But anatomists say that there are three of them! So is the basic anatomy course misleading? Not at all! The third circle, named figuratively, refers to the vessels that fill the blood and “serve” the heart itself. It deserves personal vessels, doesn't it? So, the 3rd or cardiac circle begins with the coronary arteries, which are formed from the main vessel human body- Her Majesty's aorta, and ends with the cardiac veins, merging into the coronary sinus.

It in turn opens in . And the smallest venules open into the atrial cavity on their own. It was noticed very figuratively that the vessels of the heart entwine and envelop it like a real crown, a crown. Therefore, arteries and veins are called coronary or coronary. Remember: these are synonymous terms. So what are the most important arteries and veins the heart has at its disposal? What is the classification of coronary arteries?

3 Main arteries

The right coronary artery and the left coronary artery are two whales that deliver oxygen and nutrients. They have branches and offshoots, which we will discuss later. For now, let’s understand that the right coronary artery is responsible for the blood supply to the right heart chambers, the walls of the right ventricle and the posterior wall of the left ventricle, and the left coronary artery supplies the left heart chambers.

The right coronary artery goes around the heart along the coronary sulcus on the right, giving off the posterior interventricular branch (posterior descending artery), which descends to the apex, located in the posterior interventricular sulcus. The left coronary also lies in the coronary sulcus, but on the other, opposite side - in front of the left atrium. It is divided into two important branches - the anterior interventricular (anterior descending artery) and the circumflex artery.

The path of the anterior interventricular branch runs in the recess of the same name, to the apex of the heart, where our branch meets and merges with the branch of the right coronary artery. And the left circumflex artery continues to “hug” the heart on the left along the coronary sulcus, where it also unites with the right coronary. Thus, nature created an arterial ring of coronary vessels on the surface of the human “motor” in a horizontal plane.

This is an adaptive element, in case a vascular catastrophe suddenly occurs in the body and blood circulation sharply deteriorates, then despite this the heart will be able to maintain blood supply and its work for some time, or if one of the branches is blocked by a blood clot, the blood flow will not stop, but will continue differently heart vessel. The ring is the collateral circulation of the organ.

The branches and their smallest branches penetrate the entire thickness of the heart, supplying blood not only to the upper layers, but to the entire myocardium and the inner lining of the chambers. Intramuscular arteries follow the course of the muscular cardiac bundles; each cardiomyocyte is saturated with oxygen and nutrition due to a well-developed system of anastomoses and arterial blood supply.

It should be noted that in a small percentage of cases (3.2-4%), people have such an anatomical feature as a third coronary artery or an additional one.

4 Forms of blood supply

There are several types of blood supply to the heart. All of them are a variant of the norm and a consequence individual characteristics laying of the heart vessels and their functioning in each person. Depending on the prevailing distribution of one of the coronary arteries on the posterior heart wall, they are distinguished:

1. Legal type. With this type of blood supply to the heart, the left ventricle (posterior surface of the heart) is filled with blood primarily from the right coronary artery. This type of blood supply to the heart is the most common (70%)
2. Left-handed type. Occurs if the left coronary artery predominates in the blood supply (in 10% of cases).
3. Uniform type. With approximately equal “contribution” to the blood supply of both vessels. (20%).

5 Major veins

Arteries branch into arterioles and capillaries, which, having completed cellular exchange and taking decay products and carbon dioxide from cardiomyocytes, are organized into venules, and then larger veins. Venous blood can flow into venous sinus(from it the blood then enters the right atrium), or into the atrial cavity. The most significant cardiac veins that drain blood into the sinus are:

1. Big. It takes venous blood from the anterior surface of the two lower chambers and lies in the interventricular anterior groove. The vein begins at the apex.
2. Average. It also originates at the apex, but runs along the posterior groove.
3. Small. It can flow into the middle one and is located in the coronal sulcus.

The veins that drain directly into the atria are the anterior and smallest cardiac veins. The smallest veins are not named so by chance, because the diameter of their trunks is very small; these veins do not appear on the surface, but lie in the deep cardiac tissues and open mainly into the upper chambers, but can also flow into the ventricles. The anterior cardiac veins supply blood to the right upper chamber. In this way, you can imagine in the most simplified way how the blood supply to the heart occurs and the anatomy of the coronary vessels.

Once again I would like to emphasize that the heart has its own, personal, coronary circle of blood circulation, thanks to which separate blood circulation can be maintained. The most important cardiac arteries are the right and left coronary, and the veins are large, middle, small, and anterior.

6 Diagnostics of coronary vessels

Coronary angiography is the “gold standard” in diagnosing coronary arteries. This is the most exact method, it is produced in specialized hospitals by highly qualified medical workers, the procedure is performed according to indications, under local anesthesia. The doctor inserts a catheter through the artery of the arm or thigh, and through it a special radiopaque substance, which mixes with the blood and spreads, making both the vessels themselves and their lumen visible.

Pictures and video recordings of the filling of the vessels with the substance are taken. The results allow the doctor to make a conclusion about the patency of the vessels, the presence of pathology in them, assess the prospects for treatment and the possibility of recovery. Diagnostic methods for studying coronary vessels also include MSCT angiography, ultrasonography with Doppler, electron beam tomography.

Read:

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

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

When systematizing this data, we Special attention drew on information from the surgical anatomy of the coronary arteries, basing it on the principle topographic anatomy in relation to the plan of an operation with division of the coronary arteries of the heart into segments.

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

In the right coronary artery, three segments are distinguished: I - a segment of the artery from the mouth to the origin of the branch - the artery of the acute edge of the heart (length from 2 to 3.5 cm); II - section of the artery from the branch of the acute edge of the heart to the origin 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 are divided

Rice. 51.Segmental division of coronary

arteries of the heart:

A- right coronary artery; B- left coronary artery

into two segments of 2 cm each - segments II and III. The distal portion of the anterior interventricular branch constituted segment IV. The circumflex branch of the left coronary artery to the origin of the branch of the obtuse edge of the heart is the V segment (length 1.8-2.6 cm). The distal portion of the circumflex branch of the left coronary artery was more often represented by the artery of the obtuse edge 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 the 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, and is of practical importance when choosing a method of surgical intervention in the case of coronary artery disease hearts.

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

Origin of the coronary arteries . James (1961) suggests calling the aortic sinuses from which the coronary arteries arise the right and left coronary sinuses. The orifices of the coronary arteries are located in the bulb of the ascending aorta at the level of the free edges of the semilunar valves of the aorta or 2-3 cm above or below them (V.V. Kovanov and T.I. Anikina, 1974).

The topography of sections of the coronary arteries, as indicated by A. S. Zolotukhin (1974), is different and depends on the structure of the heart and chest. According to M. A. Tikhomirov (1899), the mouths 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 aortic wall close the mouths, either at the level of the free edge of the valves, or above them, at the wall of the ascending aorta.

The level of the mouths is of practical importance. With a high position at the time of systole of the left ventricle, the mouth appears

under the impact 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 important role in the vascularization of the heart, especially its posterior diaphragmatic surface. In 25% of patients, we found a predominance of the right coronary artery in the myocardial blood supply (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 origin is rarely observed. The artery enters the coronary sulcus, located behind the base of the pulmonary artery and under the appendage of the right atrium. The section of the artery from the aorta to the acute edge of the heart (segment I of the artery) is adjacent to the wall of the heart and is completely covered with subepicardial fat. The diameter of the first segment of the right coronary artery ranges from 2.1 to 7 mm. Along the artery trunk, epicardial folds filled with adipose tissue form on the anterior surface of the heart in the coronary sulcus. Abundantly developed adipose tissue is noted along the artery from the acute edge of the heart. The atherosclerotically altered trunk of the artery along this length is clearly palpable in the form of a cord. Detection and isolation of the first segment 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 conus arteriosus, or the fatty artery - leaves directly at the beginning of the coronary sulcus, continuing down to the right at the conus arteriosus, giving branches to the conus and the wall of the pulmonary trunk. In 25.6% of patients we observed general beginning it 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 began directly from the ascending aorta and was only slightly inferior in caliber to the trunk of the right coronary artery.

Muscular branches extend from the first segment of the right coronary artery to the right ventricle of the heart. There are 2-3 vessels 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 acute edge of the heart). The artery of the acute edge of the heart, a permanent branch of the right coronary artery, arises in the area of ​​the acute edge of the heart and descends along the lateral surface of the heart to its apex. It supplies blood to the anterolateral wall of the right ventricle, and sometimes to the diaphragmatic part of it. In some patients, the diameter of the artery lumen was about 3 mm, but more often it was 1 mm or less.

Continuing along the coronary sulcus, the right coronary artery bends 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 obtuse edge of the heart (in 64% of patients).

The terminal 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 groove of the same name; 2) along the entire length of this groove to the apex of the heart; 3) the posterior interventricular branch exits onto 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, 4 to 6 branches extend into the interventricular septum at right angles, supplying blood to the conduction system of the heart.

With the right-sided type of coronary blood supply, 2-3 muscular branches extend to the diaphragmatic surface of the heart 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 upward and retract it to the left. The second segment of the artery is located superficially in the coronary sulcus; it can be easily and quickly found and highlighted. The posterior interventricular branch (III segment) is located deep in the interventricular groove and covered with subepicardial fat. When performing operations on the second 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 manipulated 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. Beginning in the left sinus of Valsalva, it is directed 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 no more than 18 mm. Isolation of the main trunk of the left coronary artery is difficult because it is hidden by the root of the pulmonary artery.

The short trunk of the left coronary artery with a diameter of 3.5 to 7.5 mm turns to the left between pulmonary artery and the base of the left appendage of the heart and is divided 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 is directed 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 the second segment 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 with subepicardial fat and muscle bridges. Isolating an artery at this location requires great care due to the danger possible damage its muscular and, most importantly, septal branches going 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 segment II of the left coronary artery, 2 to 4 septal branches extend deep into the myocardium, which participate in the vascularization of the interventricular septum of the heart.

Along the entire length of the anterior interventricular branch of the left coronary artery, 4-8 muscle branches extend 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. A significantly larger number of branches extend to the anterolateral wall of the left ventricle. From a functional point of view, the diagonal branches (there are 2 of them, sometimes 3) extending from the II and III segments of the left coronary artery are especially important.

When searching and isolating the anterior interventricular branch, an important landmark is the great 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 appendage of the heart. Its permanent branch - the branch of the obtuse edge of the heart - descends over a considerable distance at the left edge of the heart, somewhat posteriorly and in 47.2% of patients reaches the apex of the heart.

After branches depart 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 groove or along the posterior wall of the left atrium in the form of a thin trunk and reaches the confluence of the inferior vein.

The V segment of the artery is easily detected, which is located in the fatty membrane under the left atrial appendage and is covered big vein hearts. The latter sometimes has to be crossed to gain access to the artery trunk.

The distal portion of the circumflex branch (VI segment) is usually located on the posterior surface of the heart and, if necessary, surgical intervention on it the heart is raised and retracted to the left while simultaneously retracting the left ear of the heart.

The diagonal branch of the left coronary artery (VII segment) runs 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 poorly 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 perspective, the coronary bed 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 participate in the formation of the arterial ring, passing along the atrioventricular groove. The formation of the arterial loop of the heart involves the anterior descending artery from the left coronary artery system and the posterior descending artery from the right coronary artery system, or from the left coronary artery system - from the left circumflex artery with a left dominant type of blood supply. The arterial ring and loop are functional devices for development collateral circulation hearts.

Right coronary artery

The right coronary artery arises from the right sinus of Valsalva and runs in the coronary (atrioventricular) groove. In 50% of cases, immediately at the 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). extending from the right coronary artery back at a right angle into the space 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 is found 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 blood supply to the sinoatrial 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 (acute marginal artery, acute marginal branch, AMB), usually from one to three, departs from the right coronary artery, 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 at various distances, giving off 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 origin of the posterior descending artery (PDA), the RCA continues beyond the cross of the heart as the right posterior atrioventricular branch along the distal part of the left atrioventricular groove, ending in one or more posterolateral branches supplying the diaphragmatic surface of the left ventricle . On the posterior surface of the heart, immediately below the bifurcation, at the junction of the right coronary artery with the posterior interventricular groove, an arterial branch originates from it, which, piercing the interventricular septum, goes to the atrioventricular node - the atrioventricular node artery (AVN).

Left coronary artery

The left coronary artery begins 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 the anterior interventricular (left anterior descending artery, LAD) and circumflex artery (LCx) branches . In 30-37% of cases, the third branch arises here - the intermediate artery (ramus intermedius, RI), which crosses obliquely the wall of the left ventricle. The LAD and OB form an angle between themselves that varies from 30 to 180°.

Anterior interventricular branch

The anterior interventricular branch is located in the anterior interventricular groove and goes to the apex, giving off the anterior ventricular branches (diagonal artery, D) and anterior septal branches along the way. In 90% of cases, one to three diagonal branches are determined. The septal branches depart from the anterior interventricular artery at an angle of approximately 90 degrees and pierce the interventricular septum, feeding it. The anterior interventricular branch sometimes enters the thickness of the myocardium and again lies in the groove and along it often reaches the apex of the heart, where in approximately 78% of people it turns posteriorly onto the diaphragmatic surface of the heart and at a short distance (10-15 mm) rises upward along the posterior interventricular groove. In such cases, it forms the 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, Doctor of Medicine. Sciences Yu.P. Ostrovsky

At the moment, there are many options for classification of coronary arteries accepted 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 analyzed the literature on the anatomy and classification of the coronary arteries. Data from literary sources are compared with our own. A working classification of coronary arteries has been developed in accordance with the nomenclature accepted in the English-language literature.

Coronary arteries

From an anatomical point of view, the coronary artery system is divided into two parts - right and left. From a surgical perspective, the coronary bed 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 participate in the formation of the arterial ring, passing along the atrioventricular groove. The formation of the arterial loop of the heart involves the anterior descending artery from the left coronary artery system and the posterior descending artery from the right coronary artery system, or from the left coronary artery system - from the left circumflex artery with a 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

Right coronary artery(right coronary artery) arises from the right sinus of Valsalva and runs 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). extending from the right coronary artery back at a right angle into the space 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 is found 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 blood supply to the sinoatrial 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 (acute marginal artery, acute marginal branch, AMB), usually from one to three, departs from the right coronary artery, 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 at various distances, giving off 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 origin of the posterior descending artery (PDA), the RCA continues beyond the cross of the heart as the right posterior atrioventricular branch along the distal part of the left atrioventricular groove, ending in one or more posterolateral branches supplying the diaphragmatic surface of the left ventricle . On the posterior surface of the heart, immediately below the bifurcation, at the junction of the right coronary artery with the posterior interventricular groove, an arterial branch originates from it, which, piercing the interventricular septum, goes to the atrioventricular node - the atrioventricular node artery (AVN).

The branches of the right coronary artery vascularize: the right atrium, part of the anterior wall, the entire posterior wall of the right ventricle, a small section of the posterior wall of the left ventricle, interatrial septum, posterior third of the interventricular septum, papillary muscles of the right ventricle and 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 exits 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 the anterior interventricular (left anterior descending artery, LAD) and circumflex artery (LCx) branches . In 30-37% of cases, the third branch arises here - the intermediate artery (ramus intermedius, RI), which crosses obliquely the wall of the left ventricle. The LAD and OB form an angle between themselves that varies from 30 to 180°.

Anterior interventricular branch

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

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 obtuse marginal artery (obtuse marginal branch, OMB), usually from one to three. These fundamentally important arteries supply 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 off branches to the left ventricle. In the relatively rare left type (10% of cases), it reaches the level of the posterior interventricular groove and forms the posterior interventricular branch. In an even rarer case, the 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 artery of the appendage.

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 refers to 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 grooves - crux. Depending on which artery - 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 the posterior interventricular branch, which runs along the posterior interventricular groove towards the apex of the heart and supplies the posterior part of the interventricular septum. Another anatomical sign is described to determine the predominant type of blood supply. It has been noted that the branch to the atrioventricular node always arises from the predominant artery, i.e. from an artery that has highest value in feeding 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, right ventricle, posterior part of the interventricular septum, and 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 ends in short branches on the phrenic surface of the right ventricle, and the posterior surface of the left ventricle, rear end 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 “predominant type of blood supply to the heart,” although conditional, is based on anatomical structure and distribution of coronary arteries in the heart. Since the mass of the left ventricle is significantly greater than the right, 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, with any type of coronary blood supply, the left coronary artery is predominant in a physiological sense.

Nevertheless, the concept of “predominant type of blood supply to the heart” is valid, 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 lesion sites, it is proposed to divide the coronary bed into segments

The dotted lines in this diagram highlight the segments of the coronary arteries.

Thus 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. average – from 1DV to 2DV.

3. distal – after departure of the 2DV.

In the 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 3rd VTC has departed.

Right coronary artery is divided into the following main segments:

1. proximal – from the mouth to 1 VOK

2. medium – from 1 VOC to the acute edge of the heart

3. distal – before the bifurcation of the RCA into the posterior descending and posterolateral arteries.

Coronary angiography

Coronary angiography(coronary angiography) is an X-ray visualization of the coronary vessels after the injection of a radiopaque agent. The X-ray image is simultaneously recorded on 35 mm film or digital media for subsequent analysis.

At the moment, coronary angiography is the “gold standard” for determining the presence or absence of stenoses 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 determination of 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 atherosclerotic plaque, thrombus, dissection, spasm or myocardial bridge).

The data obtained determine further treatment tactics for the patient: coronary bypass surgery, intervention, drug therapy.

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

The study is carried out under local anesthesia and NLA through arterial access. The following arterial approaches are generally accepted: femoral arteries, brachial arteries, radial arteries. Transradial access has recently gained a strong position and has become widely used due to its low morbidity and convenience.

After puncture of the artery, diagnostic catheters are inserted through the introducer, followed by selective catheterization of the coronary vessels. Contrast agent administered in doses using an automatic injector. Filming is performed in standard projections, the catheters and intravener are removed, and a compression bandage is applied.

Basic angiographic projections

When carrying out the procedure, the goal is to obtain the maximum full information about the anatomy of the coronary arteries, their morphological characteristics, the presence of changes in blood vessels with precise definition localization and nature of lesions.

To achieve this goal, coronary angiography of the right and left coronary arteries is performed in standard projections. (They are described 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 analyzing a certain section of the coronary bed and allows the most accurate identification of morphological features and the presence of pathology of a given segment.

Below are the main angiographic projections indicating the arteries for which these projections are optimal for visualization.

For left coronary artery The following standard projections exist.

1. Right anterior oblique with caudal angulation.

RAO 30, caudal 25.

2. Right anterior oblique projection with cranial angulation.

RAO 30, cranial 20

LAD, its septal and diagonal branches

3. Left anterior oblique with cranial angulation.

LAO 60, cranial 20.

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