Palliative surgery for complete transposition of the great vessels. How dangerous is it? After the operation of transposition of the main arteries

Congenital abnormally located vessels emanating from the ventricles of the heart pose a threat to life. Transposition of the great vessels is the most common congenital heart disease among other defects. Observing a pregnant woman can identify a problem before the baby is born, which will help plan her treatment.

Features of the disease

The correct structure provides that the pulmonary trunk exits the ventricle on the right, which is responsible for venous blood. Through this main vessel, blood is sent to the lungs, where it is enriched with oxygen. An artery protrudes from the left ventricle. The left half is responsible for arterial blood, which is sent to a large circle to nourish the tissues.

Transposition is a pathology when the main vessels are reversed. From the right ventricle, depleted blood enters the artery and a large circle. And from the left ventricle, the blood intended to saturate the cells with oxygen again goes in a vicious circle to the lungs.

Two parallel circles are obtained, where the enriched blood cannot enter the large circle, and when it enters the lungs, it is not saturated with oxygen, because it has not given it to the tissues and has not become poor. Venous blood in a large circle immediately creates oxygen starvation of tissues.

How are abnormal arrangements of vessels for different periods of life perceived:

• Baby in the womb. A child in the womb does not experience discomfort with such a pathology, because his blood has not yet passed a large circle and it is not vital during this period.
• For a born child, it is important that at least some part of the venous blood has the opportunity to receive oxygen. The situation is rescued by the presence of other congenital anomalies. when there is a hole in it and the blood of different ventricles can communicate with each other. Part of the venous blood moves to the left ventricle and is therefore involved in the small circle. It has the ability to receive oxygen by entering the lungs. Arterial blood, partially entering the right half of the heart, goes through the artery to a large circle and prevents the tissues from falling into a critical state due to hypoxia. Also, a partial exchange of blood between the venous and arterial circulation can be carried out due to:
  • not yet closed ductus arteriosus,
  • if the atrial septum has
  • oval window.

At this stage, specialists determine when it is better to make an adjustment to the patient. Consider how long you can wait, often no more than a month. They take action so that the small and large circles do not happen to be completely isolated from each other. The child most often has a bluish color of the skin. Over time, the negative effects of oxygen starvation begin to accumulate and more and more symptoms of the disease appear.

• An adult, if the birth defects caused by this type of defect were not corrected in early childhood, cannot be viable. This is due to the fact that the results of the progression of the pathology accumulate in the body, leading to irreversible processes. There may be options if the anomaly is not very severe, but without any correction it is impossible to have a normal life expectancy.

The medical specialists tell in more detail about the features of the disease and the main method of dealing with the transposition of the great vessels in the following video:

Forms and classification

Experts distinguish four variants of violations.

1. incomplete transposition. When the main vessels depart from one ventricle, for example: the right one.
   If the vessels, by mistake of nature, have changed places, but one of them has an outlet from both ventricles.
2. Complete transposition of the great vessels. This is the name of the defect when the main arteries and the pulmonary trunk have changed places. The result is two parallel circles of blood circulation. At the same time, the blood of the venous circulation and the arterial circulation do not communicate with each other.
   Difficult case. It helps to hold out until the correction, which makes it possible to communicate with the blood of the small and large circles. It persists from the perinatal period and doctors try to delay its closure until a corrective procedure.
3. Transposition of highways, which has additional malformations of physiology. Cases are suitable here when the septum of the heart has a hole, which is a defect. However, this circumstance facilitates the condition of the newborn and makes it possible to survive until the corrective procedure.
4. Corrected form of transposition of the great vessels
   With this pathology, nature seems to have made a double mistake. As in the first case, the main main vessels are mutually displaced in places. And the second anomaly - the left and right ventricles are also in place of each other. That is, the right ventricle is located on the left and vice versa.
   This form facilitates the situation, because it does not have a strong effect on blood circulation. But over time, the consequences of pathology still accumulate, because the right and left ventricles are naturally created to carry different loads and it is difficult for them to replace each other.

Incorrect location of the main vessels (diagram)

Causes

The incorrect arrangement of the main vessels is formed during the perinatal life of the fetus during the period when the creation of the heart and vascular system occurs. This is in the first eight weeks. Why the anomalous failure occurs is not exactly known.

Factors contributing to abnormal intrauterine development of organs include:

• exposure of the expectant mother to influences:
  • contact with harmful chemicals,
  • taking medicines without the consent of a doctor,
  • exposure to ionizing radiation,
  • living in places with unfavorable ecology,
  • if the pregnant woman has been ill:
    • chickenpox,
    • SARS,
    • measles
    • herpes
    • epidemic parotitis,
    • syphilis
    • rubella;
• genetic predisposition,
• malnutrition or poor diet,
• alcohol consumption,
• diabetes mellitus in a future mother without proper control during childbearing,
• if pregnancy occurs over the age of forty,
• the disease occurs in children with other chromosomal disorders, such as Down syndrome.

Symptoms

Since patients do not survive without correction in early childhood, we can talk about the symptoms of transposition of the great vessels in newborns:

• the skin has a bluish tint,
• enlarged liver,
• dyspnea,
• rapid heart rate;
• in the future, if the child could survive without correction of defects:
  • there is a delay in physical development,
  • poorly gaining the weight necessary in accordance with age,
  • enlargement of the chest
  • the heart is larger than normal
  • puffiness.

Diagnostics

It is possible to determine the transposition of the great vessels in the fetus during its intrauterine development. This will help plan and prepare for child care. If a problem has not been identified, then at birth, cyanosis specialists suggest a heart defect.

To clarify the type of violation, there may be such procedures.

• echocardiography
  Very informative and safe method. You can determine the incorrect location of the vessels and other defects.
• X-ray pictures
  They make it possible to see the shape and size of the heart, some features of the vessels.
• catheterization
  A catheter is inserted into the heart area through the vessels. With it, you can examine in detail the internal structure of the heart chambers.
• Angiography
  One of the methods of examining blood vessels with the use of a contrast agent.

The following video will tell you what the transposition of the great vessels looks like:

Treatment

The main and only treatment for transposition of the great vessels is surgery. There are several methods to support the newborn in the period before adjustment.

Therapeutic and medicinal methods

The therapeutic method will be needed during the monitoring of the condition after the operation. The medical method is used as an auxiliary. During the preparation of the newborn for adjustment, he may be assigned to take prostaglandin E1. Purpose: to prevent the overgrowth of the arterial duct.

It exists in a child before birth, then overgrows. Keeping the duct open will help the child survive until surgery. It will remain possible to communicate with venous and arterial circulation.

And now let's talk about the operation for transposition of the great vessels.

Operation

• The first surgical intervention, which in most cases is done to the newborn as quickly as possible, is the Rashkind procedure. It consists in introducing a catheter with a balloon into the region of the heart under the supervision of the equipment.
  The balloon in the oval window inflates, thereby expanding it. Operation of a closed type (palliative).
• The operation to correct defects is a radical intervention with the use of artificial circulatory support (Zatenet operation). The purpose of the procedure is the complete correction of natural defects. The best time for its implementation is the first month of life.
• If you are late in contacting specialists for help, then sometimes the operation to move the vessels cannot be done. This is due to the fact that the ventricles have adapted and adapted to the existing load and may not be able to withstand the change. This usually applies to children over the age of one and up to two years. But experts have an option how you can help them. Surgery is performed to redirect blood flows, so that as a result, arterial blood circulates in a large circle, and venous blood in a small one.

In more detail about how the operation is performed, if the child has a transposition of the great vessels, the following video will tell:

Disease prevention

To conceive a child, one must seriously prepare, examine health, and follow the recommendations of specialists. During pregnancy, situations that are harmful should be avoided:

• to be in places with unfavorable ecology,
• do not come into contact with chemicals,
• not be subjected to vibration, ionizing radiation;
• tablets, if necessary, consult a specialist;
• take precautions to avoid infectious diseases.

But if a pathology has occurred, then the best option is to detect it before the birth of the child. Therefore, it should be observed during the bearing of the child.

Complications

The longer the child lives without adjustment, the more the body adapts to the situation. The left ventricle gets used to the reduced load, and the right ventricle to the increased one. In a healthy person, the load is distributed in reverse.

The reduced load allows the ventricle to decrease its wall thickness. If the correction is made late, then the left ventricle after the procedure may not be able to cope with the new load.

Without surgery, oxygen starvation of tissues increases, creating new diseases and shortening life. Very rarely there are complications after surgery: narrowing of the pulmonary artery. This happens if during the procedure artificial materials were used for prosthetics or because of sutures.

In order to avoid this, many clinics use:

• a special technique for sewing elements, taking into account the further growth of the highway;
• natural materials are used for prosthetics.

Forecast

After performing a corrective operation, positive results are in 90% of cases. Such patients after the procedure require long-term follow-up by specialists. They are advised not to expose themselves to significant physical exertion.

Without qualified assistance, newborns with naturally displaced vessels die in the first month of life up to 50%. The remaining patients mostly live no longer than a year due to hypoxia, which progresses.

Transposition of the great vessels: the essence of CHD, causes, treatment, prognosis

Transposition of the great vessels (TMS) is a severe anomaly of the heart, when the aorta exits the right ventricle (RV), and the pulmonary trunk - from the left. TMS accounts for up to 15-20% of all congenital heart defects (CHDs), among patients there are three times more boys. TMS is one of the most common forms of congenital heart disease along with, (VSD) and others.

When the main arteries are transposed, there is no oxygen enrichment of the arterial blood, as it moves in a vicious circle, bypassing the lungs. A small patient becomes cyanotic immediately after birth, with clear signs of heart failure on his face. TMS - "blue" defect with severe tissue hypoxia, requiring surgical treatment in the first days and weeks of life.

Causes of TMS

It is usually impossible to establish the exact causes of the appearance of pathology in a particular baby, because the mother during pregnancy could be exposed to a variety of adverse effects. A certain role in the occurrence of this anomaly can be played by:

• Viral diseases during pregnancy (rubella, chickenpox, herpes, respiratory infections);
• heavy;
• Ionizing radiation;
• The use of alcohol, drugs with a teratogenic or mutagenic effect;
• Concomitant pathology in a pregnant woman (diabetes, for example);
• The age of the mother is over 35 years old, especially if the pregnancy is the first.

It has been observed that TMS occurs more often in children with Down syndrome, the causes of which are chromosomal abnormalities, including those caused by the above reasons. Children with TMS may also be diagnosed with defects in other organs.

The influence of heredity is possible, although the exact gene responsible for the abnormal development of the heart has not yet been found. In some cases, the cause is a spontaneous mutation, while the mother denies the possibility of external influences in the form of X-rays, drugs or infections.

The laying of organs and systems occurs in the first two months of embryo development, therefore, during this period, it is necessary to protect a very sensitive embryo from all kinds of toxic factors. If the heart began to form incorrectly, then then it will not change, and signs of a defect will appear immediately after birth.

Blood flow during TMS

I would like to dwell in more detail on how blood moves through the cavities of the heart and vessels during their transposition, because without understanding these mechanisms it is difficult to imagine the essence of the defect and its manifestations.

Features of blood flow in TMS are determined by the presence of two closed, unrelated circles of blood circulation. From the biology course, everyone knows that the heart "pumps" blood in two circles. These streams are separate, but represent a single whole. Venous blood leaves the pancreas to the lungs, returning as arterial blood enriched with oxygen to the left atrium. From the LV, arterial blood with oxygen enters the aorta, heading to the organs and tissues.

In TMS, the aorta begins not in the left, but in the right ventricle, and the pulmonary trunk departs from the left. Thus, two circles are obtained, one of which “drives” venous blood through the organs, and the second sends it to the lungs and, in fact, receives it back. In this situation, there can be no talk of an adequate exchange, since the oxygenated blood does not reach organs other than the lungs. This type of defect is called complete TMS.

It is quite difficult to detect complete transposition in the fetus. On ultrasound, the heart will look normal, four-chambered, two vessels will depart from it. The diagnostic criterion for the defect in this case can be the parallel course of the main arteries, which normally intersect, as well as the visualization of a large vessel that originates in the left ventricle and is divided into 2 branches - the pulmonary arteries.

It is clear that blood circulation is disturbed to a critical level, and one cannot do without at least some possibility to send arterial blood to the organs. Strange as it may sound, other UPUs can come to the aid of a sick little heart. In particular, either the ventricles will benefit. The presence of such additional communication channels allows you to connect both circles and ensure, albeit minimal, but still the delivery of oxygen to the tissues. Additional pathways provide life support before surgery and are present in 80% of patients with TMS.

pathways of blood passage pathological for an adult partially compensate for the defect and are present in most patients

Equally important in relation to the clinic and prognosis is the state of the pulmonary circle of blood flow, the presence or absence of its overload with blood. From this position It is customary to distinguish types of TMS:

1. With overload or normal pressure in the lungs;
2. With reduced pulmonary circulation.

Nine out of ten patients are found to be overloaded with a small circle of "excess" blood. The reasons for this may be defects in the partitions, an open arterial duct, the presence of additional communication routes. The impoverishment of the small circle occurs when the LV outlet is narrowed, which occurs in an isolated form or in combination with a ventricular septal defect.

Anatomically more complex defect is corrected transposition of the great vessels. In the heart, both the chambers and the vessels are “mixed up”, but this allows compensating for blood flow disturbances and bringing it to an acceptable level. With corrected TMS, both ventricles change places with the vessels departing from them: the left atrium passes into the right ventricle, then the aorta follows, and from the right atrium the blood moves into the LV and pulmonary trunk. Such "confusion", however, ensures the movement of fluid in the right direction and the enrichment of tissues with oxygen.

Complete TMS (left) and corrected defect (right), photo: vps-transpl.ru

In the case of a corrected defect, the blood will move in the physiological direction, so the presence of an additional communication between the atria or ventricles is not required, and if it is, it will play a negative role, leading to hemodynamic disorders.

Video: TMS - medical animation (eng)

Manifestations of TMS

During fetal development, this heart disease does not manifest itself in any way, because the pulmonary circle does not work in the fetus. After birth, when the baby's heart begins to pump blood to the lungs on its own, TMS also manifests itself in full. If the transposition is corrected, then the clinic is poor, if the defect is complete, its signs will not keep you waiting.

The degree of violations with complete TMS depends on the routes of communication and their size. The more blood mixes in the heart in newborns, the more oxygen the tissues will receive. The optimal option is considered when there are sufficient holes in the partitions, and the pulmonary artery is somewhat narrowed, which prevents overloading the volume of the pulmonary circle. Complete transposition without additional anomalies is incompatible with life.

Babies with transposition of the main vessels are born at term, with normal weight or even large ones, and already in the first hours of life, signs of congenital heart disease are noticeable:

• Strong whole body;
• Dyspnea;
• Increase in heart rate.

1. The heart increases in size;
2. Fluid appears in the cavities (ascites, hydrothorax);
3. The liver is enlarged;
4. Edema occurs.

Other signs of cardiac dysfunction are also noteworthy. The so-called "heart hump" (deformation of the chest) is caused by an increase in the heart, the nail phalanxes of the fingers thicken, the baby lags behind in development, and gains weight poorly. Certain difficulties arise during feeding, since it is difficult for a child to suckle the breast with severe shortness of breath. Any movement and even crying can be an impossible task for such an infant.

If an excess volume of blood enters the lungs, then there is a tendency to infectious and inflammatory processes, frequent pneumonia.

The corrected form of TMS proceeds much more favorably. In the absence of other cardiac defects, there may be no transposition at all, because the blood moves correctly. The child will grow and develop properly according to age, and the defect can be detected by chance by the presence of tachycardia, heart murmur, conduction disturbances.

If the corrected transposition is combined with other disorders, then the symptoms will be determined by them. For example, with a hole in the interventricular septum, shortness of breath will appear, the pulse will become more frequent, there will be signs of heart failure in the form of edema, liver enlargement. Such children suffer from pneumonia.

Ways to correct TMS

Given the presence of anatomical changes in the heart, the only possible option for treating the defect is a surgical operation, and the sooner it is performed, the less irreversible consequences the disease will bring.

Emergency intervention is indicated for patients with complete TMS, and before the operation, prostaglandin preparations are prescribed to prevent the closure of the arterial duct, which allows the blood to “mix”.

In the first days of a baby's life, it is possible to carry out operations that ensure the connection of circulatory circles. If there are holes in the partitions, they are expanded, if there are no defects, they are created. The Rashkind operation is performed endovascularly, without penetration into the chest cavity, and consists in the introduction of a special balloon that expands the oval window. This intervention gives only a temporary effect for several weeks, during which the issue of radical treatment must be resolved.

The most correct and effective treatment is an operation in which the aorta returns to the left ventricle, and the pulmonary trunk to the right, as they would be normal. The intervention is carried out in an open way, under general anesthesia, the duration is from one and a half to two hours or more, depending on the complexity of the defect.

example of surgery for TMS

After the baby is immersed in anesthesia, the surgeon cuts through the tissues of the chest and reaches the heart. By this time, artificial blood flow is being established, when the role of the heart is performed by the apparatus, and the blood is additionally cooled to prevent complications.

Having opened the way to the main arteries and the heart, the doctor cuts off both vessels slightly above their attachment, approximately in the middle of the length. At the mouth of the pulmonary artery, the coronary arteries are sutured, then the aorta is “returned” here. The pulmonary artery is fixed to the portion of the aorta remaining at the outlet of the right ventricle using a fragment of the pericardium.

The result of the operation is the normal arrangement of the vascular tracts, when the aorta leaves the left ventricle, the coronary arteries of the heart also begin from it, and the pulmonary trunk originates in the right half of the organ.

The optimal period for treatment is the first month of life. Of course, you can live in anticipation of it longer, but then the intervention itself will become inappropriate. As you know, the left ventricle is thicker than the right one and is designed for a large pressure load. With a defect, it atrophies, as the blood pushes into a small circle. If the operation is performed later than the due date, then the left ventricle will not be ready for the fact that it will have to pump blood into the systemic circulation.

When time is lost, and it is no longer possible to restore the anatomy of the heart, there is another way to correct the blood flow. This is the so-called intra-atrial correction, which has been used for more than 25 years and has proven to be an effective way to treat TMS. It is shown to children who did not undergo the above operation on time.

The essence of intra-atrial correction is to cut the right atrium, remove its septum and sew in a “patch” that directs venous blood from the large circle to the left ventricle, from where it goes to the lungs, while the pulmonary veins return oxygenated blood to the “right” heart and then - into the abnormally located aorta. Thus, without changing the location of the main arteries, the movement of blood in the right direction is achieved.

Prognosis and results of treatment

When a baby with vascular transposition is born, his parents are very concerned about not only the operation, but also what will happen after, how the child begins to develop and what awaits him in the future. With timely surgical treatment, the prognosis is quite favorable: up to 90% or more of patients live a normal life, periodically visiting a cardiologist and undergoing a minimum of examinations to monitor the work of the organ.

With complex defects, the situation may be worse, but still, in most patients, the quality of life is acceptable. After intra-atrial correction surgery, about half of the patients experience no restrictions in life, and its duration is quite long. The other half may suffer from arrhythmias, heart failure, which is why it is recommended to limit physical activity, and women are warned about the risks of pregnancy and childbirth.

Today, TMS is a completely curable anomaly, and hundreds of children and adults who have successfully undergone surgery are proof of this. Much depends on the parents, their faith in success and the desire to help their child.

Or for short TMS is one of the types congenital malformations of the heart, in which the main vessels ( aorta and) leave the heart in the wrong order. This malformation can be detected already at the very early stages of pregnancy, so quite often young mothers learn about this problem long before childbirth. In this article, we will try to explain what transposition of the great vessels is, can a child be born and live with such a diagnosis, and what should be done in this case?

Transposition of the great vessels There are several types: simple, TMS in combination with heart septal defects, and corrected TMS. Critical malformations requiring treatment in the first days of life include simple TMS.

At TMS vessels completely change their places, that is, aorta departs from the right ventricle of the heart, and - from the left ventricle. In this case, both circles blood circulation(large and pulmonary) are completely isolated from each other. It turns out that the blood of the pulmonary circle is enriched with oxygen all the time, but it does not enter the large circle. And blood from the systemic circulation, poor in oxygen, cannot enter the lungs. In such a situation, the life of a child would be impossible.

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Still, with TMS, blood between circles blood circulation can mix. In particular, blood can enter the small (pulmonary) circulation through. This vessel functions in all children during fetal development, and closes after birth. There are drugs that can support ductus arteriosus open. Therefore, it is very important that the child simple TMS received these medicines. This will stabilize the child's condition before surgery.

Before the birth of the child, at the stage prenatal development, such a UPU does not interfere with the life and development of the fetus, since the pulmonary circulation in the fetus practically does not function, all blood circulates only in a large circle through and open ductus arteriosus. Therefore, children are born full-term, completely normal, but immediately very cyanotic.

After birth and the first breath, the situation changes dramatically - the pulmonary circulation begins to function separately, and the size becomes insufficient to mix the blood in the large and small circles. In addition, every hour it becomes less and less, which aggravates the situation. Therefore, children with simple transposition of the great vessels are in a life-threatening situation and require urgent care immediately after delivery.

Of course, if TMS is combined with other malformations of the heart, for example, or VSD, then this situation is more beneficial for the newborn, since these defects allow blood flow to flow from one circle to another, so their life threat becomes less strong, and in surgeons have time to choose the right tactics surgical treatment. However, in any case, with complete transposition of the great vessels, surgery is necessary, the only question is when to do it - immediately after childbirth, or you can wait.

Therefore, if during pregnancy you find out that the fetus may have transposition of the great vessels, then the most important thing to do is to find a specialized maternity hospital that cooperates with the cardio center so that the child can be operated on immediately after. There are similar maternity hospitals in the main large cities, such as Moscow, St. Petersburg, Novosibirsk, Tomsk, Penza, and Samara.

However, it is important to understand that radical correction of complete TMS- a rather complicated operation, which is successfully performed only in some cities of our country. In all other cardio centers, only the Rashkind procedure can be performed - this is an auxiliary operation that eliminates a critical situation and makes it possible for a child with TMS to live for a few more weeks. However, for a complete correction of TMS, the child still needs to be transported to one of the cities where the leaders of our country are located. We can recommend Moscow, Novosibirsk, Tomsk, Samara, Penza.

Remember that the hardest surgery to completely correct TMS, must be performed within the first month of life! Later, it becomes problematic to perform a radical correction, because. the left ventricle "weaned" to work as a systemic one and after a radical operation it may not be able to cope with the load. Therefore, if the terms of radical correction are missed, the child first undergoes an auxiliary operation, which prepares the left ventricle for radical correction.

Another subspecies transposition of the great vessels is corrected TMS. In this case, nature, as it were, made a mistake twice: it was not the aorta with the pulmonary artery that were confused, but the ventricles of the heart. At corrected TMS venous blood enters the left ventricle, but the pulmonary artery departs from it, and arterial blood from the lungs returns to the right ventricle, but the aorta departs from it. That is, blood circulation is not affected. The child looks absolutely healthy. Problems come later. The fact is that the right ventricle is not adapted to work on a large circle of blood circulation. Over time, right ventricular function deteriorates

Since both circles of blood circulation function normally, there is no life-threatening situation in this case, and children can live without surgery for a very long time. We have participants on the forum of parents of children with congenital heart disease who are over 30 years old and have adjusted TMS. However, these children may have some problems. For example, the fact that the right ventricle of the heart is not anatomically designed to supply the systemic circulation leads to the fact that these children still lag behind in development compared to healthy children, albeit slightly. Also corrected TMS often combined with other heart anomalies (ventricular septal defects, etc.)

Transposition of the great arteries, or d-transposition, is the most common cause of cyanosis in newborns and the main cause of death in children with cyanotic heart disease in the first year of life. Previously, this defect was fatal, but now, thanks to the advent of palliative and radical operations, the prognosis for it has improved significantly.

Morphology and hemodynamics

During transposition of the main arteries, the systemic venous return from the right atrium enters the right ventricle, and from there it is ejected into the aorta departing from the right ventricle. Pulmonary venous return passes through the left atrium and left ventricle and returns to the lungs through the pulmonary trunk extending from the left ventricle. Normally, two circles of blood circulation are connected in series, but here they are disconnected. Life with such a circulation is only possible if there are connections between circles that allow oxygenated blood from the lungs to enter the arteries of the systemic circulation, and blood from the veins of the systemic circulation to enter the pulmonary arteries. In more than half of patients with transposition of the main arteries, the interventricular septum is intact and intracardiac shunt is carried out only through a distended foramen ovale or, more rarely, through an atrial septal defect of the ostium secundum type. The cyanosis is very pronounced. With a large ventricular septal defect, the blood mixes better, so SaO 2 in these patients is higher. A patent ductus arteriosus can be found in about half of newborns with transposition of the great arteries, but in most cases it closes and obliterates shortly after birth. Rarely, the ductus arteriosus remains wide open; this condition is dangerous, requires timely diagnosis and treatment. In addition, there may be varying degrees of left ventricular outflow tract obstruction due to the subvalvular membrane or fibromuscular cord. Common AV canal, AV valve atresia, severe pulmonic valve stenosis and atresia, coarctation of the aorta, and right-sided aortic arch in transposition of the great arteries are rare.

Transposition of the great arteries leads to severe hypoxemia, metabolic acidosis, and heart failure. SaO 2 depends on the discharge of oxygenated blood from the vessels of the small circle to the vessels of the large circle and venous blood - in the opposite direction. The magnitude of the reset, in turn, depends on the size of the messages that provide it: foramen ovale, atrial septal defect such as ostium secundum, ventricular septal defect, patent ductus arteriosus, dilated bronchial arteries. A noticeable effect on hemodynamics, especially with a large ventricular septal defect, is obstruction of the outflow tract of the left (functionally right) ventricle and an increase in pulmonary vascular resistance; with high resistance to blood flow from the left ventricle, pulmonary blood flow decreases, the return of oxygenated blood from the pulmonary veins decreases, and SaO 2 falls. The dissociation of the two circles of blood circulation, as a rule, leads to an increase in cardiac output of both ventricles, followed by dilatation of the heart cavities and heart failure. This is aggravated by the fact that the coronary arteries receive oxygen-poor blood from the veins of the large circle.

Damage to the pulmonary vessels in transposition of the main arteries and a large ventricular septal defect is more common and progresses much faster (according to both morphological studies and cardiac catheterization) than in a ventricular septal defect with normal origin of the main arteries. Severe pulmonary vascular obstruction is found in approximately 75% of children with transposition of the great arteries and a large ventricular septal defect older than 1 year. Obstructive pulmonary vascular disease does not develop with concomitant stenosis of the pulmonary artery valve, with timely closure of the ventricular septal defect and early surgical narrowing of the pulmonary trunk. Morphological examination reveals moderate pulmonary vascular disease in many children with ventricular septal defect already at the age of 3-4 months. Therefore, narrowing of the pulmonary trunk or a radical correction of the defect should be carried out at an earlier age. Even with an intact interventricular septum, 5% of children who did not die in the first months of life have a significant lesion of the pulmonary vessels.

Clinical manifestations

With an intact ventricular septum, the condition becomes critical in the first hours after birth, while with a large ventricular septal defect, cyanosis can be mild and symptoms of heart failure appear only a few weeks after birth. A sign of poor blood mixing is cyanosis in an apparently healthy child; nurses are often the first to notice. Early diagnosis requires high suspicion for this malformation because, with the exception of persistent cyanosis and progressive tachypnea in the first hours after birth, the baby may appear healthy and there may be no changes on the ECG and chest x-ray.

On auscultation, the II tone is loud, unsplit, best heard from above at the left edge of the sternum, however, with careful auscultation, a slight splitting of the II tone with a quiet pulmonary component can often be heard. With an intact interventricular septum, there are practically no noises in newborns, although a short mesosystolic murmur of II-III degree of loudness can be heard in the middle at the left edge of the sternum. Older children may present with a loud, rough systolic murmur, indicating a ventricular septal defect or left ventricular outflow tract obstruction. In the first case, a pansystolic murmur is best heard in the middle and below at the left edge of the sternum; and in the latter - decreasing, best heard in the middle at the left edge of the sternum, but carried towards the upper part of the right edge of the sternum.

With transposition of the main arteries and a large ventricular septal defect, severe heart failure and moderate cyanosis develop by the 3-4th week. Tachypnea and sweating increase. Cyanosis may increase, but due to good mixing of the blood, it often remains relatively mild. There are congestive rales in the lungs and severe hepatomegaly.

In newborns, the ECG is not informative, since the deviation of the electrical axis of the heart to the right and other signs of right ventricular hypertrophy are also observed in the norm. However, the persistence of positive T waves in the right chest leads after 5 days indicates pathological hypertrophy of the right ventricle. Later, infants with an intact ventricular septum show clear signs of right atrial and right ventricular hypertrophy. With a large ventricular septal defect, signs of left ventricular hypertrophy may also appear in the first months of life.

Diagnostics

Chest x-ray

Changes on the radiograph can be from gross to almost imperceptible. Immediately after birth, the shadow of the heart is not enlarged, but it increases in the first or second week after birth. The pulmonary vascular pattern is initially normal or only slightly enhanced, its noticeable enrichment appears later. The oval heart shadow, which is classic for transposition of the main arteries, with a narrow upper mediastinum and a small thymus shadow, allows you to immediately make a diagnosis, but in newborns it occurs only in a third of cases.

With a large ventricular septal defect, a large rounded shadow of the heart and a significantly enriched pulmonary vascular pattern are detected shortly after birth.

echocardiography

Doppler echocardiography is the main method for assessing the morphology of the defect and hemodynamic features. The aortic root is located in front and to the right of the pulmonary trunk, it departs from the right ventricle, and the pulmonary trunk, located behind and to the left, from the left; the morphology of the ventricles corresponds to their location. Doppler study specifies the direction and magnitude of intracardiac discharge at different levels; evaluate ventricular pressure.

Cardiac catheterization

Cardiac catheterization in newborns is performed for therapeutic purposes - for balloon atrial septostomy. Often it is carried out under the control of echocardiography right at the patient's bedside. Diagnostic catheterization is performed in a cardiac catheterization laboratory. SO 2 in the pulmonary artery is higher than in the aorta. With an intact interventricular septum, the pressure in the right and left ventricles immediately after birth may be the same; however, within a few days, left ventricular pressure drops to 2-fold or more of right ventricular pressure (unless there is left ventricular outflow tract obstruction). Prior to a balloon atrial septostomy, pressure in the left atrium is often higher than in the right.

Right ventriculography shows a high anterior aorta originating from the right ventricle. Determine the presence of a ventricular septal defect, the patency of the arterial duct. With left ventriculography, the pulmonary trunk extending from the left ventricle is filled; it is possible to assess the integrity of the interventricular septum and the presence of obstruction of the outflow tract of the left ventricle.

Treatment

After stabilization of the condition with the help of a balloon atrial septostomy, alprostadil infusion, tracheal intubation with transfer to mechanical ventilation and correction of metabolic disorders, the patient is examined for several days. It is necessary to identify and characterize all concomitant defects, as well as to clarify the course of the coronary arteries. In the absence of pulmonic valve stenosis or subvalvular right ventricular outflow tract obstruction, arterial switch surgery is performed. This operation is the best treatment for transposition of the great arteries. After it, the left ventricle ejects blood into the vessels of the large circle; at the same time, it was shown that in the medium term after the operation, the normal function of the left ventricle is preserved and the frequency of postoperative arrhythmias is low. The operation consists in crossing the main arteries, sewing them to the desired semilunar valves and transplanting the orifices of the coronary arteries into the base of the pulmonary trunk (functioning after the operation as the aortic root). Since the left ventricle ejects blood into the pulmonary trunk, the resistance in which quickly decreases, the pressure in it drops and the mass of the myocardium decreases. Therefore, with an intact interventricular septum or its minor defect, the operation should be performed before the 8th week of life, while this has not happened yet. Early postoperative mortality after single-stage arterial switching in large centers is less than 5%. Repeated operations (most often it is the elimination of postoperative stenosis of the pulmonary arteries) are required in 5-10% of cases. When transposing the main arteries with a large ventricular septal defect, the main difficulties are associated with left ventricular failure, pulmonary hypertension, and early damage to the pulmonary vessels. In some cases, myocardial ischemia occurs due to impaired blood flow in the transplanted coronary arteries. Early arterial switching surgery with closure of the ventricular septal defect has significantly improved the prognosis of this group of patients: the five-year survival rate reaches 90%.

Transposition of the great arteries with obstruction of the outflow tract of the left ventricle

In transposition of the great arteries with an intact interventricular septum, there may be mild or moderate subvalvular obstruction of the outflow tract of the left ventricle. The causes of obstruction are myocardial hypertrophy (dynamic obstruction) or subvalvular membrane or fibromuscular cord (permanent obstruction). This band often forms where the interventricular septum bulges into the cavity of the left ventricle (due to high pressure in the right) and approaches the septal leaflet of the mitral valve. Obstruction is usually mild; excision or anastomosis for defect correction is required only in case of severe stenosis.

In transposition of the great arteries with a ventricular septal defect and severe subvalvular obstruction of the outflow tract of the left ventricle, the clinical picture resembles tetralogy of Fallot. Severe cyanosis and cyanotic crises may occur from birth; the pulmonary vascular pattern on the radiograph is depleted. If the obstruction is not very severe, the clinical manifestations are not so pronounced at first, but they increase with age. The localization and severity of obstruction is assessed by echocardiography and left ventriculography.

If a newborn with transposition of the great arteries and a ventricular septal defect has severe left ventricular outflow tract obstruction or severe pulmonic valve stenosis or atresia, an anastomosis between the systemic and pulmonary circulations is most safely performed. It is very difficult to correct the defect and it is better to do it after 1-2 years. Surgical correction (Rastelli operation) consists in closing the ventricular septal defect with a patch so that the aorta is connected to the left ventricle. After that, the right ventricle is connected to the pulmonary artery using an external anastomosis with a valve; this bypasses left ventricular outflow tract obstruction.

Transposition of the great vessels is one of the most common heart defects in infants and the most common cyanotic congenital heart disease in infancy (20-30 cases per 100,000 newborns). TMS occurs in 5-7% of children with CHD. Among patients with this defect, boys predominate, with a ratio of M/D = 1.5-3.2/1. Among patients with transposition of the main arteries, 10% have malformations of other organs. Less common is the so-called congenital corrected TMS, the clinical picture and treatment tactics of which differ significantly from TMS.

Morphology
The first anatomical description of TMS was given by M. Baillie in 1797, and the term "transposition" itself was introduced in 1814.

Farre as a characteristic of a defect in which the main arteries are discordant to the ventricles, and the atria and ventricles are concordant to each other. In other words, morphologically, the right ventricle is connected to the morphologically right ventricle, from which the aorta originates completely or mostly, and morphologically, the left atrium is connected to the morphologically left ventricle, from which the pulmonary artery originates. In the most common variant of TMS, D-TMS, the aorta is located on the right and in front and the pulmonary artery is on the left and behind the aorta.

The term "corrected transposition" refers to another type of defect in which there is atrioventricular and ventriculoarterial discordance. In corrected transposition, the aorta is located to the left of the pulmonary artery.

Most authors refer to a defect with isolated ventriculoarterial discordance as simple TMS, while the combination of TMS with other defects (usually VSD and pulmonary stenosis) is referred to as complex forms of TMS. Among all cases of D-transposition of the main arteries, 50% occur with intact VSD, another 25% with VSD, and about 20% with VSD and pulmonary stenosis. In so-called simple transposition, there are no additional cardiac anomalies other than a patent foramen ovale and persistent ductus arteriosus. When TMS is combined with VSD (which occurs in 40-45% of patients), about a third of such patients have small interventricular defects that do not have serious hemodynamic significance.

VSDs are the most common concomitant cardiac anomalies. They are small, large and can be localized in any part of the partition. Small membranous or muscular defects may close spontaneously over time. Sometimes there are VSDs of the atrioventricular canal type associated with a single AV valve. Sometimes there may also be a displacement of the tricuspid valve to the left with its location above the interventricular septum (straddling tricuspid valve) and pancreatic hypoplasia.

Simultaneously with TMS, other additional defects may occur - most often PDA or coarctation of the aorta, coronary anomalies. For D-TMS with intact VSD, coronary anomalies are more common than for D-TMS with VSD. LV outflow tract obstruction occurs in less than 10% of cases with TMS with an intact IVS and is usually dynamic due to displacement of the IVS to the left, since the pressure in the right ventricle is higher than in the left. If the septum is displaced forward and to the right, then there is a displacement of the pulmonary trunk with its location above the IVS plus subaortic stenosis. In such cases, one should also expect the presence of anomalies in the structure of the aortic arch, such as hypoplasia, coarctation, and other forms of its break.

Obstruction of the LV outflow tract occurs in 1/8-1/3 cases and more often in combination with an interventricular defect than with intact TMS. Rarely, obstruction is caused by abnormalities such as the fibromuscular tunnel, fibrous membrane, and abnormal attachment of the atrioventricular valve leaflets.

Coronary anatomy
Although the anatomy of the epicardial branches of the coronary arteries varies, the two sinuses of Valsalva at the aortic root always face the pulmonary artery and give rise to the main coronary arteries; they are called coronary sinuses (facing sinuses).

Since the great arteries are side by side, the coronary sinuses are anterior and posterior, while the non-coronary sinus faces to the right. If (as usual) the aorta lies in front and on the right, then the coronary sinuses are on the left in front and on the right behind. Most often (in 68% of cases), the left coronary artery departs from the coronary sinus, located on the left anterior, and gives rise to the left anterior descending and circumflex branches, and the right coronary artery departs from the coronary sinus on the right rear. Often, the circumflex branch is absent, but on the other hand, several branches depart from the left coronary artery, supplying the lateral and posterior surfaces of the left ventricle. In 20% of cases, the circumflex branch originates from the right coronary artery (originating from the coronary sinus on the right rear) and passes behind the pulmonary artery along the left atrioventricular sulcus. In this situation, the left anterior descending artery arises separately from the coronary sinus at the left anterior.

These two types of coronary anatomy occur in over 90% of D-TMS cases. Other varieties include a single right coronary artery (4.5%), a single left coronary artery (1.5%), inverted coronary arteries (3%), and intramural coronary arteries (2%). With intramural coronary arteries, the orifices of the coronary arteries are located at the commissures, and two orifices can be observed in the right sinus or a single orifice that gives rise to the right and left coronary arteries.

Hemodynamic disorders
With TMS, the pulmonary and systemic circulations are separated (parallel circulation), and the newborn survives only during the functioning of the fetal communications (ductus arteriosus, open foramen ovale). The main factors determining the degree of saturation of arterial blood with oxygen are the number and size of communications between the systemic and pulmonary circulation. The volume of blood flow in the lungs is much higher than normal due to these communications and low pulmonary vascular resistance. Therefore, systemic saturation is most dependent on the so-called effective pulmonary and systemic blood flow - the amount of desaturated blood from the systemic blood flow coming from the large to the pulmonary circulation for oxygenation (effective pulmonary blood flow - ELK) and the volume of oxygenated blood that returns from the small circle to the big one for oxygenation. gas exchange at the capillary level (effective systemic blood flow - ESC). The volumes of ELS and ESCs must be equivalent (intercirculatory mixing), otherwise the entire volume of blood will move into one of the circulation circles.

Usually, mixing blood through the foramen ovale and the closing ductus arteriosus is not enough for complete tissue oxygenation, so metabolic acidosis quickly develops and the child dies. If the patient lives due to defects in the septa of the heart or PDA, then severe pulmonary hypertension with obstructive pulmonary vascular disease quickly joins. Insufficiently high LV afterload leads to the progressive development of its secondary hypoplasia.

Timing of symptoms
The timing of the onset of symptoms depends on the degree of mixing of blood between the parallel circles of the pulmonary and systemic circulation. Usually, signs of TMS are visible from the first hours after birth (from the moment of constriction of the ductus arteriosus and closure of the foramen ovale), but sometimes they appear after several days or weeks of life if volumetric fetal shunts continue to function or there is a VSD.

Symptoms
Newborns with TMS are more likely to be born with normal body weight. The neonatal picture of the defect varies from a deceptively healthy appearance of an outwardly healthy baby to acute total heart failure and cardiogenic shock. Parallel circulation is accompanied by severe hypoxemia, so central cyanosis is the leading symptom of the defect. Blue or purple coloration of the skin and mucous membranes suggests TMS. Not only the timing of the appearance of cyanosis, but also its degree are closely related to the morphological features of the defect and the degree of mixing of blood between two parallel circles of blood circulation. On initial physical examination after birth, the baby may appear to be generally healthy except for the single symptom of cyanosis.

In patients with intact VSD (i.e., without VSD), cyanosis appears within the 1st hour of life in 56%, and by the end of the first day of life - in 92%. The condition worsens very quickly due to constriction of the arterial duct, within 24-48 hours after birth, with increasing dyspnea and signs of multiple organ failure. PaO2 usually remains at the level of 25-40 mm Hg. and almost does not increase when giving 100% oxygen. In the absence of an ASD and a small foramen ovale, severe acidemia occurs. At the same time, most patients do not have a heart murmur, and the boundaries of the heart are not expanded until the 5-7th day of life. In a small proportion of patients, a weak systolic murmur may be heard at the left edge of the sternum in the middle or upper third due to the acceleration of blood flow in the LV outflow tract or the closing ductus arteriosus. Even a chest x-ray and ECG performed during the first days of life in a maternity hospital may be normal. The defect can be recognized at this time with an immediate echocardiogram.

If the newborn has a large PDA or VSD, the diagnosis of TMS may not be made in time due to the apparent well-being. Cyanosis in these cases is insignificant and appears only at the moments of crying, the boundaries of the heart in the 1st week of life are normal, and the noise may not be heard even if there are messages between the left and right sections due to the equality of pressures in them. In these cases, the pronounced tachypnea with relatively weak cyanosis draws attention. Such classic signs of PDA as continuous systole-diastolic murmur, jumping pulse are observed in less than half of the patients in this group. When pulmonary vascular resistance decreases significantly, symptoms of severe heart failure increase. Newborns with TMS and a large PDA are at risk of developing necrotizing enterocolitis due to retrograde diastolic outflow of blood from the aorta to the pulmonary artery and ischemic bowel injury.

Diagnostics
On a frontal chest x-ray in the first days and even weeks of life in children with so-called simple TMS, the chest x-ray may look normal or with a slight expansion of the cardiac shadow, although 1/3 of patients do not have cardiomegaly at all. The vascular pattern is not enhanced in 1/3-1/2 patients and at first there is no oval heart shape, although the vascular bundle is narrowed. The right aortic arch is seen relatively rarely - in 4% of children with simple TMS and in 11% with TMS plus VSD.

After 1.5-3 weeks, in almost all patients without LV outflow tract obstruction, cardiomegaly progresses due to an increase in both ventricles and RA, increasing with each subsequent study. The oval shape of the heart shadow in the form of an egg lying on its side and the narrowing of the shadow of the upper mediastinum (narrow vascular bundle) are characteristic. Clearly expressed signs of hypervolemia of the pulmonary circulation.

In some patients, even after adequate balloon atrioseptostomy, there is no sharp increase in the vascular pattern of the lungs in the first 1–2 weeks of life, and low arterial O2 saturation can persist. This suggests the presence of persistent vasoconstriction of the arterial vessels of the pulmonary circulation, as a result of which an insufficient increase in the volume of pulmonary blood flow minimizes the effectiveness of atrioseptostomy. Previously, when surgical correction was delayed for months after balloon atrial septostomy, some of these patients experienced a sharp deterioration in their condition with an increase in cyanosis due to a progressive decrease in pulmonary blood flow due to dynamic narrowing of the LV outflow tract.

When TMS is combined with VSD, cardiomegaly and increased pulmonary vascular pattern are significantly pronounced in comparison with simple TMS. Vessels in the roots of the lungs are sharply dilated, and on the periphery of the lung fields often look narrowed due to vasoconstriction. The left contour of the cardiac shadow may be deformed due to the imposition of the shadow of a significantly dilated pulmonary trunk.

On the electrocardiogram, the electrical axis of the heart is usually deviated to the right, signs of hypertrophy of the pancreas and PP are observed (Fig. 5.49). During the first days of life, the ECG may be normal, and after 5-7 days, a pathological deviation of the electrical axis of the heart to the right, increasing in dynamics, appears in patients with TMS without VSD. When TMS is combined with VSD, in 1/3 of patients the electrical axis of the heart is located normally. Biventricular hypertrophy is observed in 60-80% of children with TMS plus VSD. A deep Q-wave occurs in V6 in 70% of patients with TMS and large VSD, and in intact VSD in 44%. Signs of isolated left ventricular hypertrophy are very rare, with TMS in combination with a large interventricular defect, a left-shifted tricuspid valve, and RV hypoplasia.

With a doppler echocardiogram - visualization of the discordant passage of the main arteries from the ventricles from the epigastric (subcostal) access. At the same time, the aortic origin from the pancreas, the parallel course of the aorta and the pulmonary artery, the departure of the pulmonary artery from the left ventricle and the branch of the pulmonary artery are visible. Additional signs in conventional transthoracic projections are the mutual spatial arrangement of the aorta and pulmonary artery side by side, without the usual decussation, as well as the departure of the coronary arteries from the main vessel emanating from the pancreas. RV and PP are significantly dilated. In the projection of the four chambers from the top, the characteristic of the vessel located behind is specified, i.e. pulmonary artery with characteristic division into right and left branches. With the help of dopplerography, blood shunt through the foramen ovale or ASD and arterial duct, significant regurgitation on the tricuspid valve are determined. Additionally, echocardiography clarifies the presence and localization of VSD, LV outflow tract obstruction (or pulmonary stenosis), as well as the presence of other additional anomalies (the size of the PDA, the presence of aortic coarctation, the shape and functional state of the mitral and tricuspid valves).

Laboratory data - in the study of blood gases, PaO2 and SpO2 are reduced, the level of PaCO2 is increased, the content of bicarbonate and pH are reduced. In the general blood test, increasing polycythemia due to an increase in the number of erythrocytes, increased hemoglobin and hematocrit levels.

TMS combined with large VSD
Newborns with this defect may initially be asymptomatic, except for mild cyanosis, usually occurring during crying or feeding. Noise may be minimal at first, or systolic murmur of 3-4/6 gradation according to Loude, as well as III heart sound, gallop rhythm, splitting and amplification of II tone at the base of the heart are heard. In such cases, the defect is most often recognized by the symptoms of congestive heart failure, usually at 2-6 weeks of age. In addition to shortness of breath, there are severe sweating, fatigue during feeding, poor weight gain, gallop rhythm, grunting breathing, tachycardia, hyperexcitability, hepatomegaly, edema, and increased cyanosis.

If the VSD is also accompanied by pulmonary artery stenosis (LV outflow tract obstruction) or even pulmonary atresia, then pulmonary blood flow is reduced, and such patients have severe cyanosis from birth, in combination with clinical signs, as in Fallot's tetralogy with pulmonary atresia.
Damage to the central nervous system

Congenital anomalies of the CNS are rare in patients with TMS. Hypoxic-ischemic damage to the CNS can occur in patients with inadequate palliative correction or if it has not been carried out. The most common debut of CNS lesions is a sudden onset of hemiparesis in a newborn or infant. The risk of such a complication is increased in children with hypochromic microcytic anemia in combination with severe hypoxemia. At an older age, cerebrovascular accidents usually occur against the background of severe polycythemia, which leads to persistent hypoxemia.

The natural evolution of vice
Without treatment, 30% of patients with TMS die on the 1st week, 50% - by the end of the 1st month, 70% - during the first 6 months and 90% - up to 12 months of life.
Observation before surgery

Immediately after birth, continuous intravenous infusion of prostaglandin E1 or E2 is started (starting rate 0.02-0.05 µg/kg per minute, then the dose is titrated to effect), which is continued until palliative or radical surgical correction is performed. As a rule, due to severe heart failure (or apnea against the background of the introduction of prostaglandin E1), respiratory support (ALV) is required. Additionally, diuretics and inotropic drugs are prescribed (usually dopamine infusion ≥5 mcg / kg per minute).

Terms of surgical treatment
In the neonatal period, palliative or immediately radical surgery is required.

Types of surgical treatment
If it is impossible to perform arterial switching immediately after birth, then a palliative operation is performed - a mini-invasive atrioseptostomy with a Rashkind balloon under echocardiographic or angiographic control, in which sufficient mixing of blood is achieved with a defect size in the oval fossa of 0.7-0.8 cm.

Over the past four decades, radical surgical correction of TMS has evolved from the previously used Senning or Mustard procedures with the creation of intra-atrial tunnels that direct blood from the veins of the small and large circulation to the ventricles corresponding to these circles, to the most physiological arterial switch operation (switch), in which the aorta and the pulmonary artery is moved to their normal anatomical positions. The most technically difficult stage of the operation is the simultaneous movement of the coronary arteries. Arterial switching is best performed in the first days or weeks of life. The optimal period for radical correction with D-TMS is the first 14 days of life. If for some reason the child is delivered later, pulmonary artery banding + systemic pulmonary anastomosis is performed first. For arterial switch surgery after banding, an interval of 2 weeks is considered the most acceptable. There are criteria favorable for arterial switching operation: 1) LV wall thickness - as normal for age; 2) the ratio of pressure in the left ventricle to the pressure in the right ventricle> 70%; 3) the values ​​of the LV volume and the mass of its myocardium, equal to the age. H. Yasui et al. (1989) found that in these cases the following conditions are safe enough for arterial switching operation: 1) excess of LV mass over the norm by 60%; 2) LV pressure >65 mm Hg; 3) LV/RV pressure ratio >0.8.

If TMS is combined with pulmonary stenosis and VSD, then, if necessary, palliative operations are performed in the first months of life (the type of which depends on the leading hemodynamic disorders), and the main interventions that correct the defect are performed later. If severe cyanosis is observed, balloon or open atrial septostomy and systemic pulmonary anastomosis are required first to improve blood mixing. Other patients have a more balanced combination of these defects, so that they can feel good for many months and without palliative interventions. Then the classical corrective procedure for these patients is the Rastelli operation, which allows directing blood flow from the LV through the intraventricular tunnel into the aorta and provides communication of the RV with the pulmonary artery through a valve-containing conduit.

The result of radical surgical treatment
In recent years, in foreign cardiac surgical centers, early postoperative mortality ranges from 1.6 to 11-13% with D-TMS with an intact interventricular septum in the absence of other high-risk factors. The factors of increased risk of postoperative mortality are: additional defects in the structure of the heart, congenital coronary anomalies, prematurity or low body weight at the time of the operation, long time of cardiopulmonary bypass during the operation (>150 min). Coronary anomalies, such as the origin of all three coronary arteries from one sinus or the intramural course of the coronary arteries, especially burden the prognosis.

The incidence of such residual complications as supravalvular pulmonary stenosis, neoaortic insufficiency, coronary artery strictures is quite low.
Postoperative follow-up

Early experience with arterial switch surgery was accompanied in a number of cases by supravalvular pulmonary stenosis, the incidence of which decreased after the introduction of a pericardial patch to compensate for tissue deficiency after dissection of the sinuses of Valsalva in the neopulmonary artery.

Myocardial ischemia due to coronary insufficiency remains the most common cause of postoperative mortality, but in recent years it has become less common as myocardial protection techniques and coronary repositioning have advanced.

The most common cause of reoperation after arterial switching is pulmonary artery stenosis, which can occur with a frequency of 7 to 21%. It is formed for various reasons, but most often due to inadequate growth of the pulmonary trunk, when the stenosis is localized in the region of the suture, the pancreas. Sometimes there is neoaortic regurgitation (5-10%), which is mild and does not progress. Postoperative complications are more likely to occur after intra-atrial switch operations; these include atrial arrhythmias, ventricular dysfunction, and obstruction of artifactual atrial messages.