Right aortic arch: what is it, causes, development options, diagnosis, treatment, when is it dangerous? X-ray examination A. Rupture of aortic aneurysm: symptoms

If the right IV branchial arch is preserved after birth, right aortic arch. Identified as the only anomaly, and also in combination with a mirror arrangement of the organ, with. With this anomaly, the ascending aorta goes up and to the right from the trachea and esophagus, spreads over the right bronchus, and goes down either to the right or, passing behind the esophagus, to the left of the spine. Right-sided aorta often appears without pathological symptoms. In these cases, the arterial ligament is located in front of the trachea and is not stretched, and if it passes behind the esophagus, it can be long. If the ligament arteriosus or patent ductus arteriosus passes from pulmonary artery to the aorta to the left of the trachea and behind the esophagus, a ring is formed surrounding the esophagus and trachea. The arterial ligament presses on the esophagus and trachea. The left subclavian artery in one case passes in front of the trachea or diverticulum of the residual IV of the left branchial arch. The diverticulum is located at the junction of the right arch with the descending aorta. Diverticula are remnants of the left IV branchial arch with various options for the origin of the subclavian arteries.

Clinical symptoms

In children, a right-sided aortic arch may cause constant hiccups. In the absence of a constricting ring closed by an arterial ligament, the course of the disease is asymptomatic. In adults with aortic sclerosis, the symptoms of dysphagia intensify. Respiratory disorders worsen after eating.

Varieties described in the literature

The aortic arch extends over the right main bronchus and descends from the right side of the spine as the descending aorta. The left common carotid and left subclavian arteries depart from the innominate artery. The ligamentum arteriosus attaches to the innominate artery.

The right-sided aortic arch is located in the neck, at the level thyroid cartilage, on the right side of the larynx. The aortic arch is formed in this case from the third pair of the right branchial arch. The patent ductus arteriosus enters the descending aorta opposite the left subclavian artery. The left common carotid artery arises from the ascending aorta and ascends anteriorly and to the left of the trachea. The ductus arteriosus is involved in a vascular ring that compresses the trachea and esophagus.

X-ray data. When inhaling - insufficient aeration of the lungs, when exhaling - hyperaeration. Signs of infection in the lungs. The protrusion of the aorta is visible on the right side of the mediastinal shadow, and on the left the normal shadow of the aortic arch is absent. On the left side there is often a shadow image of a diverticulum located where the aortic bulge would normally be. The descending aorta is sometimes displaced towards the pulmonary fields. In the first oblique position, the trachea is shifted forward, and the shadow of the diverticulum is detected at the level of the arch between the trachea and the spine. In the left oblique position, the descending aorta bends. Lateral radiographs show a trachea filled with air in the upper normal part and clearly narrowed in the lower part.
Esophageal examination. A barium swallow reveals a sharp narrowing of the esophagus and compression of its left lateral and posterior surface, if there is a diverticulum or an arterial ligament in a closed ring. Above the notch on the posterior surface of the esophagus, a separate defect running obliquely upward and to the left is determined. It is caused by compression of the left subclavian artery, which passes behind the esophagus to the left clavicle. The shadow of the left subclavian artery, passing behind the esophagus, is located above the shadow of the arch right aorta. A pulsating left aortic diverticulum is seen posterior to the esophagus. The esophagus is displaced anteriorly.
Examination of the trachea with lipidol. If there are symptoms of tracheal compression, a contrast study of it shows the localization of the aortic ring. The introduction of lipoidol into the trachea reveals an elongated notch along right wall trachea caused by the nearby aortic arch, a notch on the anterior wall of the trachea from compression by the pulmonary artery and a depression on the left wall of the trachea from the ligament arteriosus. If there is no compression of the trachea, then there is no point in examining it with lipidol.
Angiocardiography. It is produced when a right-sided aortic arch is combined with other congenital heart defects.

Differential diagnosis

A right-sided aortic arch can cause a picture similar to that observed with. The anterior image shows the right-sided aortic arch in children with an enlarged shadow thymus gland is not clearly identified. However, the gland does not move the esophagus forward. Tumors in posterior section The upper mediastinal shadow can simulate the right aortic arch, but they do not pulsate. The normal prominence of the aortic arch on the left is preserved. With aneurysms of the innominate artery or left descending aorta, a shadow of the descending aorta is always detected.

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The heart anlage appears in an embryo 1.5 mm in parietal-coccygeal length at the end of the 2nd week of development. In the mesenchyme between the endoderm and the visceral layer of the splanchiotome, at the level of the not yet closed foregut, two vesicles are formed, lined with endothelium, which develop into the endocardium (primordium endocardiale). Subsequently, both protrude into the body cavity. Around them, myoepicardial plates are formed from the visceral mesoderm, giving rise to the myocardium and epicardium (primordium epimyocardiale).
L. Streeter believes that the myocardium develops from a specialized part of the visceral mesoderm. The part of the myoepicardial plate from which the myocardium develops is separated from the primary endocardium by a “myocardial space” filled with jelly-like tissue - “heart jelly”. It later forms endocardial cushions (see below). The distribution of tissue material in the myoepicardial plate may be uneven, which causes the occurrence of cardiac malformations - the absence of the myocardium of a part of the heart (the absence of the myocardium of the right ventricle is usually found - Uhl's anomaly), defects of the valve apparatus.
When the body of the embryo separates and the intestinal tube closes, the anlages of the heart come closer and then close, and their internal walls disappear and both anlages turn into a two-layer heart tube - a tubular heart, cor tubulare simplex (Fig. 2), having 2 mesenteries, mesocardia, ventral and dorsal, which, together with the parietal mesoderm, limit the two primary pericardial cavities.
Rice. 2. Embryonic anlage of the heart (diagram according to M. Clara, 1963).

A - paired heart anlage; b - approaching the bookmark; c - fusion of the primordia and formation of the heart tube; 1 - neural groove; 2 - chord; 3 - primary segment; 4 - rudiment of the myoepicardial plate; 5 - endocardial tube; 6 - secondary body cavity; 7 - neural tube; 8 - dorsal aorta (steam room); 9 - intestinal rudiment; 10 - secondary body cavity; 11 - myoepicardial plate; 12 - foregut; 13 - pleuropericardial cavity; 14 - myoepicardial plate; 15 - endocardium.
The parietal mesoderm gives rise to the pericardium itself. The ventral mesentery is exposed reverse development and after its disappearance, a single pleuropericardial cavity is formed. Subsequently, when the heart tube moves, the common cavity of the embryo is divided into abdominal and thoracic, as well as the single pleuropericardial cavity into separate cavities of the pleura and pericardium. This separation occurs through the formation of a diaphragm, the development of which is in connection with the location of the vessels approaching the heart (yolk and umbilical veins). Along the course of these vessels, a transverse septum, septum transversum, is formed from the mesenchyme, which, however, does not reach the dorsal wall of the body and, as a result, does not completely delimit the thoracic and abdominal cavity. Later, 2 serous folds grow from the dorsal wall, called pleuroperitoneal folds, plicae pleuroperitoneales. They turn into a pleuroperitoneal membrane, which closes with the transverse septum, resulting in the formation of a continuous diaphragm. The division of the thoracic cavity into the cavities of the pericardium and pleura occurs due to the formation first of pleuropericardial folds, and then of the membranes of the same name.

Rice. 3. Embryonic development hearts (diagram).
a - tubular heart: 1 - venous section (primary atrium); 2 - arterial section (primary ventricle); 3 - primary aortas; 4 - pericardium; 5 - venous sinus; 6 - vitelline vein; 7 - umbilical veins; b - sigmoid heart: 1 - venous sinus; 2 - arterial section (primary ventricle); 3 - arterial trunk; 4 - pericardium; 5 - venous section; 6 - common cardinal veins; c - three-chambered heart: 1 - ventricle; 2 - right atrium; 3 - sixth arterial arch; 4 - ascending aorta; 5 - arterial cone; 6 - left atrium; 7 - pericardium.

The line of transition of the parietal plate of the pericardium into the epicardium during development shifts cranially and dorsally. Therefore, the pericardial sections of the vessels appear to lie to a greater or lesser extent in the pericardial cavity.
As a result of rapid growth, the heart tube moves downward into chest cavity, while it narrows and bends. It is already possible to distinguish its departments. The posterior expanded end of the heart tube, called the venous sinus, sinus venosus, flows into 2 common cardinal veins (Cuvier’s ducts), V. V. cardinales communes, which collect blood from the body of the embryo, 2 umbilical veins, v. v. umbilicales, carrying blood from the villous membrane of the placenta, as well as 2 vitelline veins, v. v. vitellinae, bringing blood from the yolk bladder (Fig. 3, a). Anterior to the sinus venosus is the primary atrium, atrium primitivum, and the middle part of the tube following it is the primary ventricle, ventriculus primitivus. From the atrium, blood enters the primary ventricle through the narrow atrioventricular canal, canalis atrioventricularis. From anterior section From the heart tube there are 2 primary (ventral) aortas, each of which participates in the formation of 6 aortic arches.
The development of the heart can be divided into 4 main stages.

Sigmoid heart

Uneven growth of the heart tube leads not only to a change in its position, but also to a more complex shape and structure. In this case, initially the lower end of the heart tube, in the process of its growth, moves upward and backward, and the upper end moves downward and anteriorly - a sigmoid heart, cor sygmoideum, is formed. The formation of a sigmoid heart leads to the fact that the right ventricle will subsequently be located on the right side of the ventricular septum. However, the bending of the heart tube and its S-shaped tortuosity can occur in the opposite direction and then the right ventricle will form on the left side, that is, it will be inverted.
In embryos 2-3 mm long (end of the 3rd, beginning of the 4th week of development) in the sigmoid heart, cor sigmoideum, there are: venous sinus, into which the common cardinal, umbilical and vitelline veins flow, the following venous section, arterial a section curved in the shape of a knee and located behind the venous one, followed by a small expansion - the bulbus cordis, and then the arterial trunk (Fig. 3, b). During this period, the heart begins to contract.

Two-chambered heart

In a further stage of development, the venous and arterial parts of the heart grow and a deep constriction appears between them. In this case, both sections are connected only through a narrow and short atrioventricular canal formed at the site of the constriction, in which the endocardial atrioventricular tubercle - the anlage of the valve apparatus - becomes visible. At the same time, two large outgrowths are formed from the venous section, covering the lower part of the arterial trunk and representing the primary ears of the heart. Both knees of the arterial part of the heart begin to gradually fuse with each other. The wall separating them disappears and thus one common ventricle of the heart, ventriculus primitivus, is created. In this case, the primary ventricle is separated by a groove, sulcus bulboventricularis, from the next part - the bulb of the heart, bulbus cordis, which has a spiral septum, septum spirale, directing blood into the arterial trunk (Fig. 3, c).
The primary ventricle communicates with the bulb of the heart through the bulboventricular foramen, ostium bulboventriculare. In addition to the umbilical and vitelline veins, 2 common cardinal veins flow into the venous sinus moving posteriorly, through which blood flows from the entire body of the embryo. The venous sinus at the stage of a two-chambered heart has a horizontal part, pars transversa, and 2 horns, left and right, cornua sinister et dexter, into which veins flow. The sinus venosus communicates with the primary atrium through the sinoatrial orifice, ostium sinuatrialis. having a valve, valvula sinuatrialis.
In the formed two-chamber heart of the embryo, 4.5 mm long (4th week of development), there are: venous sinus, common atrium, surrounding with its ears the arterial trunk, the common ventricle connected to the atrium by the atrioventricular canal, the bulb of the heart and the arterial trunk, delimited from the bulb by a groove corresponding inside to the bulboventricular foramen and the endocardial tubercle, tuber endocardiale, giving rise to the valves. At this stage of development there is only big circle blood circulation; the small circle develops later due to the development of the lungs. At this stage, the development of the heart may stop and the newborn has a two-chambered heart, cor biloculare.

Three-chambered heart

At the 4th week of development inner surface In the upper posterior part of the atrium, a crescent-shaped fold appears - the primary atrial septum (septum primum), which grows down towards the middle of the atrioventricular canal (Fig. 4, a). The resulting septum in the embryo, 7 mm long (5th week of development), divides the common atrium into two - right and left. The wall of the atrioventricular canal thickens and 2 atrioventricular openings appear in it on the right and left, connecting both atria with the common ventricle. The division of the atria is still incomplete, since there is an oval window in the septum.
Next to the first, the second atrial septum, septum secundum, is formed (Fig. 4, b, c). It also has an oval foramen (second), but it is located somewhat posterior to the first oval foramen and, as a result, is covered over a larger area by the first interatrial septum. Subsequently, the first septum is transformed into the valve of the oval opening, and the thickened edge of the second septum, delimiting the oval opening, remains as the edge of the oval fossa, limbus fossae ovalis.
In continuation embryonic period The blood pressure in the left atrium is low, as a result of which blood flows freely into it from the right atrium. After birth due to the onset pulmonary respiration the blood pressure in the left atrium becomes significant and the valve of the oval opening closes it, and later fuses with the septum. However, in some people the process of delineation of the atria may not be completed, as a result of which defects in the development of the heart will be observed after birth: complete absence interatrial septum, patent foramen ovale or patent atrial septum, preservation of the common atrioventricular canal. In addition, heart development may stop at the three-chamber heart stage.

Rice. 4. Embryonic development of the chambers of the heart and its partitions (scheme according to B. Petten, 1959).

Frontal sections of the heart of embryos. The epicardium is indicated by a solid dark line, the myocardium by oblique shading, the endocardial cushion tissue by dots, and an embryo 4-5 mm long: 1 - primordial septum; 2 - atrioventricular canal; 3 - interventricular septum;
b - embryo 6-7 mm long: 4 - interventricular septum; 3 - cushion of the atrioventricular canal; 1 - primary septum; 2 - false septum;
c - embryo 8-9 mm long: 1 - false septum; 2 - secondary foramen ovale; 3 - primary septum; 4 - atrium wall; 5 - cushion of the atrioventricular canal; 6 - interventricular foramen;
d - embryo 12-15 mm long: 1 - second septum; 2 - primary septum; 3 - secondary foramen ovale; 4 - interventricular foramen; 5 - cushion of the atrioventricular canal; 6 - second septum (caudal part); 7 - primary septum; 8 - false septum;
d - embryo 100 mm: 1 - false septum; 2 - second partition; 3 - oval hole in the septum primum; 4 - oval hole in the second septum; 5 - primary septum; 6 - leaflet of the atrioventricular canal; 7 - interventricular septum;
a - newborn: 1 - border ridge; 2 - second partition; 3 - membranous part interventricular septum; 4 - interventricular septum: 5 - papillary muscle; 6 - leaflet of the atrioventricular canal; 7 - second partition; 9 - oval hole.

Four-chambered heart

Almost simultaneously with the formation of the interatrial septum (5-6th weeks of development), a longitudinal muscular septum is formed on the inner surface of the common ventricle, growing upward towards the atrioventricular canal to the interatrial septum (see Fig. 4). A septum also appears in the truncus arteriosus, merging with that of the ventricle and dividing the truncus arteriosus into 2 arterial vessels- ascending aorta and pulmonary trunk. Part of the septum of the truncus arteriosus extends into the ventricles, where it connects with the interventricular septum. The junction - the membranous part of the septum - differs from the lower muscular part in the presence of only connective tissue layers.
Thus, embryos 10-12 mm long (6th week of development) already have a four-chambered heart with an arterial trunk divided into 2 sections. However, sometimes the connection of the septa of the ventricle and the arterial trunk may not occur, as a result of which they remain incomplete separation of the ventricles (non-closure of the interventricular septum). In addition, disruption of the division of the arterial trunk causes the formation of narrowings and movements of the right or left arterial cones or the initial parts of the aorta and pulmonary trunk, which appear after birth. IN in rare cases Uneven division of the ventricles occurs, with the right one being in its infancy, which may be incorrectly diagnosed as a narrowing of the pulmonary trunk.
In parallel with the process of dividing the heart into 4 chambers, the valves of its openings are formed. The rudiments of semilunar valves arise in the bulb of the heart in the form of an endocardial tubercle, which is divided into 4 endocardial cushions, forming 3 semilunar valves in the separated trunks (aorta and pulmonary trunk).
The venous sinus in the four-chambered heart also undergoes great changes. Its right part merges with the right atrium, the left - with the disappearance of the left common cardinal vein (left duct of Cuvier) narrows and turns into the coronary sinus of the heart. The right common cardinal vein (right duct of Cuvier) becomes the superior vena cava. In addition, the inferior vena cava drains into the right atrium. The outgrowths of the endocardium of the venous sinus form the valves of the inferior vein and the coronary sinus of the heart.
Initially, the pulmonary veins open into the left atrium with a common trunk, but then the walls of the common trunk, as well as the wall of the venous sinus, form back wall the left atrium, and all four pulmonary veins thus find themselves opening directly into the atrium. Disruption of the heart development process leads to various types congenital malformations of the position of large vessels, the anatomy of which will be described below.
The presented brief data on the development of the heart provide a basis for analyzing the existing differences in the structure of the heart, its parts, the valve apparatus, nervous and vascular systems. In addition, they have important when considering birth defects hearts.

Development of the aorta and pulmonary trunk

In vertebrates, according to the paired heart rudiment, 2 ventral and 2 dorsal aortas are formed, connected by 6 pairs of branchial aortic arches, arcus aortica (I-VI) (Fig. 5). The distal parts of the aortas form common trunks: ventral arterial trunk, truncus arteriosus, dorsal dorsal aorta, aorta dorsalis. In mammals, 2 the anterior pairs of aortic arches disappear before the posterior ones are formed.

Rice. 5. The development of the aorta and the transformation of the arterial arches are indicated by numbers (according to B. Petten, 1959, as amended).
a - general plan of the location of the primary aortic arches and branchial arterial arches; 1 - left ventral aorta; 2 - left dorsal aorta; 3 - common dorsal aorta; 4 - arterial trunk; 5 - branchial arterial arches; 6 - external carotid artery; 7 - internal carotid artery;
b - early stage transformations of the branchial arterial arches: 1 - left common carotid artery; 2 - aortic arch; 3 - left pulmonary artery; 4 - ductus arteriosus: 5 - descending aorta; 6 - left subclavian artery; 7 - segmental arteries; 8 - right subclavian artery; 9 - arterial trunk; 10 - right pulmonary artery; 11 - brachiocephalic trunk; 12 - right common carotid artery; 13 - external carotid artery; 14 - internal carotid artery; c - definitive derivatives of the arches: 1 - left common carotid artery; 2 - aortic arch: 3 - ductus arteriosus; 4 - pulmonary trunk; 5 - left subclavian artery; 6 - descending aorta: 7 - right subclavian artery; 8 - vertebral artery; 9 - brachiocephalic trunk; 10 - right common carotid artery.

Therefore, in the development of the aorta and pulmonary trunk in humans, the ventral and dorsal aortas, their common trunks and aortic trains III, IV and VI are important. The remaining aortic arches undergo reverse development. In the process of reduction of the aortic arches, the cranial parts of the dorsal and ventral aortas go towards the construction carotid arteries, the caudal part of the right dorsal aorta - to create the right subclavian artery, the caudal part of the left dorsal aorta and the dorsal aorta - to the descending part of the aorta, III pair the aortic arches turns into the initial parts of the internal carotid arteries. On the right, the III aortic arch, together with the IV arch, is transformed into the brachiocephalic trunk, the IV aortic arch on the left intensively grows and forms the definitive aortic arch, arcus aortae definitivus. Truncus arteriosus At the stage of division of the common ventricle, the heart is divided into 2 parts: the ascending aorta and the pulmonary trunk (see above). The bulb of the ascending aorta and the semilunar valves of the aorta and pulmonary trunk are formed from the endocardial tubercle of the bulb of the heart (see above). In this case, the VI pair of lateral arches loses connection with the truncus arteriosus and connects with pulmonary trunk and forms the pulmonary arteries, the left VI aortic arch maintains its connection with the left dorsal aorta, forming the ductus arteriosus. The left subclavian artery develops from the segmental branch of the left dorsal aorta.

Development of the vena cava

In early embryos, somatic venous system symmetrical. There are 2 anterior and 2 posterior cardinal veins, v. V. precardinales et postcardinales, connecting into 2 common cardinal veins, v. v. cardinales communes (ducts of Cuvier) and flowing into the venous sinus of the still tubular heart. Subsequently, the heart moves into the chest cavity and, as a result, the common cardinal veins move from a transverse position to a longitudinal one and turn into 2 superior vena cava. An anastomosis, anastomosis precardinalis, is formed between the anterior cardinal veins, through which blood from the left anterior cardinal vein passes into the right anterior cardinal vein and then through the right common cardinal into the heart. This is the future left brachiocephalic vein. In this regard, part of the left anterior cardinal vein disappears. From the left common cardinal vein, which has lost connection with the anterior cardinal vein, the coronary sinus of the heart is formed. Next, the anterior cardinal veins turn into internal jugular veins. Segmental veins extending into the skin upper limb, enlarge and connect on the right with the anterior cardinal vein, which forms the right brachiocephalic vein, and on the left with the intercardinal anastomosis.
The inferior vena cava is a complexly developing vessel resulting from the fusion and expansion of local veins.

Anomalies in the course of the aorta from the point of view of blood circulation in themselves are usually not significant. Anomalies in the development of branches also do not affect the fate of the child, but can cause complaints. Their significance is always determined by whether they occur alone or with other, possibly combined, anomalies of cardiac development. In the latter case, other cardiac development anomalies play a decisive role. Of the many options, we will focus here only on the most common and permitted operations.

A) Right aortic arch. The aortic arch turns to the right, and above the right main bronchus turns back behind the heart. Or it runs all the way along the right side of the spine and only at the level of the diaphragm passes to left side or at the higher thoracic segment it crosses the spine. This developmental anomaly occurs in such a way that the artery of the left IV branchial arch, from which normal development an aortic arch appears, atrophies, and instead the aortic arch is formed by the artery of the right IV branchial arch. The vessels departing from it originate in reverse order compared to the norm. In approximately 25% of cases, this developmental anomaly is associated with Fallot's tetralogy. By itself, it does not affect blood circulation and does not cause clinical symptoms. The diagnosis is important from the point of view of surgery for combined developmental anomalies. IN infancy This developmental anomaly is more difficult to determine by X-ray examination, and in childhood easily. In the sagittal direction, the aortic bulb is visible not on the left, but on the right side of the sternum. If the superior vena cava is shifted to the right, then the shadow large vessels The aortic bulb expands and can often be distinguished even when X-rayed, and can almost always be distinguished when photographed. On anteroposterior examination, the esophagus is located on the left side of the aorta and forms a concave depression to the right, in which the pulsation is directed to the left. In the right anterior oblique position, no impression from the aorta is visible on the esophagus. In the left anterior oblique position, there is a right-facing concavity with a left-facing pulsation. In infants, when filming in oblique positions, the aorta, due to its small size, does not in every case form a characteristic depression. Using angiocardiography, the position of the aortic arch and descending aorta can be clearly identified.

B) Right-sided aortic arch with left-sided descending aorta. The aortic arch is formed from the artery of the right IV branchial arch, but the Botallian duct or subclavian artery arising from the artery of the left VI branchial arch, arising from the descending aorta, in front of the spine between the esophagus and trachea, with a sharp bend, pulls the vessel to the left side. The aortic arch bends behind the esophagus to the left side, expands the median shadow and forms a deep depression behind the esophagus, clearly visible in both oblique positions.

IN) Right-sided aortic arch with right-sided descending aorta and aortic diverticulum. Along with the right-sided aortic arch and the descending aorta, a rudimentary left-sided aortic root is preserved, from which the subclavian artery arises. The diverticulum is located behind the esophagus and forms a deep depression on its posterior surface. If it extends beyond the esophagus, then on sagittal examination it appears in the form of a mediastinal shadow with a border convex to the right.

G) Double aortic arch occurs if during development the arteries of both the right and left IV branchial arches are preserved, the two vessels formed from them encircle the esophagus and trachea and behind them unite into the descending aorta. One arch is usually thinner than the other or is retained only as a rigid beam. During X-ray examination, two aortic arches, ring-shaped encircling the esophagus, form a bilateral impression of a contrasting shadow.

D) From anomalies of the subclavian artery the most common is the right subclavian artery arising on the left side. It can arise from the aorta itself or from its diverticulum. This artery turns between the VIth cervical and the IVth thoracic vertebrae above the aorta and behind the esophagus on the right side and, possibly, located between the esophagus and the trachea or in front of the latter. Thus, depression from the vessel is usually observed on the posterior surface, less often (during the course between the trachea and the esophagus) on the anterior surface of the esophagus.

E) Regarding origin of brachiocephalic vessels Numerous options may exist. The left-side innominate artery may arise from the right-sided aortic arch, but in other cases all four large vessels depart separately. These deviations are insignificant from the point of view of life, but when diagnosing combined developmental anomalies and surgical resolution, it is important to know them. In simpler cases, the diagnosis can also be made by X-ray examination. In case of an uncertain diagnosis - if surgery is planned - our assumptions are confirmed by angiocardiography or aortography. The vessels are usually clearly visible, their contrasting shadow can be traced far away.

As we have already indicated, anomalies in the development of the aortic arch and its branches themselves rarely affect the fate of the patient (aneurysm, spinal atresia, etc.). If they compress the esophagus or trachea, they can cause subjective and objective symptoms. Compression of the trachea is accompanied frequent bronchitis, laryngitis, tracheitis, breathing may be wheezing. Compression of the esophagus leads to difficulty swallowing, which makes feeding difficult for infants and small children.

The above vascular anomalies often occur in an unaffected heart, but in other cases they will join other anomalies of cardiac development, for example, a right-sided aortic arch to Fallot's tetralogy. If necessary, an improperly draining vessel or double arc aortas can be removed surgically. In the case of combined anomalies of the heart and great vessels, the latter may force the surgeon to change the method of operation.

Absence of aortic arch. The absence of an aortic arch occurs in early embryonic life due to an abnormal development of the arteries of the branchial arches. The descending aorta is a direct continuation of the pulmonary artery, and the connection between them is carried out by the duct of Botallus. The aortic arch usually ends at the origin of the left subclavian artery. The vessels leaving the ascending aorta provide blood top part body, and to the lower part of the body blood flows from the right ventricle through the ductus Botallus. Hemodynamically, this defect can be considered last resort stenosis of the aortic isthmus associated with patent Botallov duct. This primarily places the load on the right half of the heart, because, along with the pulmonary circulation, it also has to support a significant part of the systemic circulation.

Of the clinical symptoms, the most obvious is the difference in skin color between the upper and bottom parts bodies. The skin of the upper body has normal color, while the skin of the lower body is cyanotic. Between blood pressure, measured at the extremities of the two body parts, there is no significant difference.

X-ray symptoms are primarily characteristic of excessive load right half hearts. The shadow of the right ventricle is enormous, the shadow of the conus pulmonary and pulmonary artery is very large. The electrocardiogram is characterized by hypertrophy of the muscles of the right half of the heart.

When the arch develops from the right rather than the left branchial arch, a right-lying aorta is obtained. With the development of the aortic arch, a double arch is formed from the left and right primary branchial arches. The right aorta, passing behind the esophagus to the left side of the spine, can cause compression of the esophagus, and the double arch can cause compression of the esophagus and trachea. Anomalous origin of the right subclavian artery directly from the aorta also causes compression of the esophagus (Fig. 2).

Surgical treatment of these anomalies is individual in each case, based on accurate diagnosis(based on X-ray contrast examination of the aorta and arteries) and consists of ligating and crossing the formations compressing the esophagus and trachea, and transferring the mouth of the vessels (for example, the right subclavian artery) to another place (new anastomosis with the aorta).

Narrowing of the isthmus - coarctation of the aorta (Fig. 3). According to Bonnett's classification, coarctation of infantile and adult types is distinguished. The first is located proximal to the arterial (botallian) duct (preductal type), the second is distal to it (postductal type).

Coarctation of the adult type is usually shorter, while the infantile type is more extensive. In approximately 10% of cases with coarctation of the aorta, the ductus arteriosus functions, and then clinical picture The disease depends on whether this duct is located in front of the narrowed area or after it. In the latter case, the clinical picture is due to the discharge venous blood from the pulmonary artery to the distal aorta. Coarctation of the aorta is always accompanied by significant development of collaterals that provide arterial blood bypassing the narrowed area. These are anastomoses of the internal thoracic artery with the intercostal arteries and the superior epigastric artery with the inferior epigastric. Excessive development and aneurysmal expansion of the intercostal arteries lead to usurization of the ribs, characteristic of coarctation. Hypertension is determined upper sections body (up to 200 mm Hg or more) and hypotension distal to the site of coarctation. A sharp sound is heard systolic murmur on the aorta and in the interscapular space. Treatment is surgical.

In young children, it is usually possible to perform aortic resection with end-to-end anastomosis (Fig. 4). In adults, either replacement of the resected section of the aorta (Fig. 5) with a plastic prosthesis, or expansion of the narrowed section of the aorta with a “patch” of synthetic tissue is used.

From aortic diseases the most common are atherosclerosis (see), aortic aneurysm (see).

IN lately aortitis is also isolated as an independent nosological form (see). Aortitis is sometimes accompanied by occlusion of the vessels extending from the aorta (for example, truncus brachiocephalicus). Surgical treatment in case of occlusion of vessels (Fig. 6, 7) extending from the aorta, it consists of restoring their lumen (thrombendarteriectomy), bypass surgery, or resection of the obliterated area and replacing it with a graft. See also Blood vessels (operations).

Characteristic.
Persistence of the aortic arch is a congenital (congenital) anomaly. It is caused by non-closure of the canal between the aorta and the pulmonary artery (ductus arteriosis), which thus compresses the esophagus and has an indirect compressive effect on the trachea.
During the process of ontogenesis, the transition from the gill circulation to the pulmonary circulation in the fetus occurs with the formation of six pairs of aortic arches, which are then transformed into the arteries of the small (pulmonary) and systemic (systemic) circulation circles. The formation of the aortic arch is normally associated with the transformation of the left fourth aortic arch.
The main clinical sign is Dysphagia (difficulty swallowing). Secondary inhalation pneumonia often occurs.
Nevertheless clinical signs may also appear during milk feeding, and almost all dogs are diagnosed before 2 years of age. There are also dogs in which the development of signs of this disease manifests itself at a later age.

Susceptibility: Dogs, Cats, Horses

Etiopathogenesis.
With a developmental anomaly, the aorta develops from the right fourth aortic arch. As a result, the aorta is located not to the left of the esophagus, but to the right. The ductus botallus, which runs from the aortic arch to the pulmonary artery, in this case tightens the esophagus in a ring. When the puppy eats thick, bulky food, it will accumulate in the precordial portion of the esophagus, leading to the formation of a diverticulum.

Clinical signs.
Sick puppies are developmentally delayed and their weight decreases. After almost every feeding, they belch undigested food.

Summary clinic:
1. Auscultation: abnormal sounds of the upper respiratory tract;
2. Auscultation: Abnormal pulmonary or pleural sounds, rales: wet and dry, whistling;
3. Dyspnea (difficulty breathing, with open mouth);
4. Abdominal distension;
5. Dysphagia (difficulty swallowing);
6. Slow growth; Swelling in the neck area;
7. Cough;
8. Fever, pathological hyperthermia;
9. Presence of food in the nasal cavity;
10. Obstruction (blockage) of the esophagus;
11. Polyphagia, extremely increased appetite;
12. Losing body weight
13. Weight loss, cachexia, general exhaustion;
14. Precomer salivation, ptyalism, salivation"
15. Vomiting, regurgitation, emesis;
16. Heart murmurs;
17. Increased frequency breathing movements, polypnea, tachypnea, hyperpnea;
18. Depression (depression, lethargy);

The diagnosis is made on the basis of:.
- contrast radiography of the esophagus (esophagography),
- aortography,
- pathoanatomically during autopsy

Contrast esophagography technique.
The animal is allowed to swallow 50 ml of a thick suspension of barium sulfate in water and two photographs are immediately taken, covering the chest and neck area in frontal and lateral projections.
On a lateral radiograph, precordial dilatation of the esophagus is noticeable. In this case, in the dorsoventral projection, the right-sided location of the aorta is visible.

Differential diagnosis.
This developmental anomaly must be differentiated from megaesophagus and achalasia of the esophagus, which are characterized by expansion of the esophageal tube all the way to the diaphragm.

Forecast at timely treatment favorable.

Treatment.
It's only possible surgery. The course of the operation is the same as for closing the persistent ductus botallus. The arterial ligament stretching the esophagus is ligated and cut.
In this case it is much easier, since the duct is almost always obliterated and the ligament is longer than usual. The operation is completed by placing tightening seromuscular plastic sutures on the enlarged wall of the esophagus.