Where are operations performed for transposition of the great vessels? b

One of the very serious heart pathologies, which also develops even before birth, is transposition great vessels. Such an abnormal disorder of the heart structure is extremely severe and requires urgent surgical intervention. Otherwise, the survival rate of patients with this diagnosis is extremely low. What is transposition of the great vessels (TMS), how it manifests itself and how the pathology is treated, we will learn from the material below.

What is transposition of the great vessels?

Transposition of the great vessels is complex congenital pathology heart disease, in which the location of the main cardiac vessels is anatomically incorrect. In this case, the aorta branches from the right heart chamber, and the pulmonary artery from the left. That is, the vessels abnormally changed their location to the exact opposite. With such localization of the main heart vessels, a serious disturbance of blood circulation in the body occurs. That is, the pulmonary artery transports blood to the lung area, where it is saturated with oxygen. But then, due to an anomaly, the same blood returns to the right ventricle, when it should have been sent to the left chamber of the heart. In turn, the aorta incorrectly transports blood, which again returns to the left chamber. As a result, there is a complete local (separate) blood supply to the entire body and separately to the lungs. Similar condition represents very serious threat for the life of a newborn, while the fetus in the womb can still develop quite normally with such an anomaly. The disease code according to ICD is Q20.3.

Important: according to statistics, almost 50% of newborns with this diagnosis do not even survive to 2 months. More than 60% of young patients do not survive to one year. On average, in the absence of timely surgical intervention, newborns live 3–20 months.

Causes of pathology

Transposition of the great vessels in newborns develops, as mentioned above, exclusively in utero (embryonic). This happens in the first 8 weeks of gestation. The reasons for this abnormal embryogenesis are:

genetic predisposition;
transferred expectant mother viral infections (chickenpox, ARVI, measles, rubella, herpes, mumps, syphilis, etc.);
exposure to radiation on mother and fetus;
taking a certain group of medications;
lack of vitamins in the body of a pregnant woman;
long-term toxicosis;
history of diabetes mellitus in a pregnant woman;
alcohol abuse;
late birth (after 35 years).

Important: TMS is often diagnosed in babies with Down syndrome.

Classification of transposition of the great vessels

Depending on the anomalous type The location of the main cardiac vessels TMS is classified in cardiology into three types. The classification looks like this:

TMS is simple. In this case, the main vein and aorta completely changed their positions. And if during intrauterine development this anomaly does not affect the health of the fetus in any way, since the blood mixes through the open arterial duct, then in a newborn baby this same duct closes as unnecessary. As a result, the process of normal blood mixing is disrupted. If pathology is detected early in a child, the cardiologist prescribes a series of medical supplies, which do not allow the duct to close. Against the background of such therapy, urgent surgical intervention is indicated. This only chance to save a little patient. Otherwise, death is inevitable.
Simple TMS with defects (atrial and interventricular septa are defective). In this case, a hole is formed in one of the named partitions in utero. At first glance, this is a good sign, indicating that the small and large circles of blood circulation are in interaction. However, this does not save the baby, but rather, on the contrary, it delays the moment of detection of cardiac pathology. So, if the hole is very small, then all the signs of pathology are present, and the diagnosis can be made before the situation becomes hopeless. If the hole does not have a small diameter, then the exchange of blood flow occurs to a degree sufficient to ensure the vital functions of the body. But at the same time, all vessels of the small circle suffer critically due to the developing arterial hypertension. Most often, in this case, neither an already made diagnosis nor possible surgical intervention can save the baby, since little patient at this point it is no longer operable.
TMS corrected. Here, the pathology is characterized by an abnormal location not of the vessels themselves, but of the heart chambers. That is, during intrauterine development, the right and left ventricles change places. With this structure, the systemic and pulmonary circulation occur relatively normally, although abnormally. But such patients often have obvious mental and mental retardation. physical development, since the right heart chamber is not intended to physiologically serve the systemic circulation.

Features of hemodynamics with different types of TMS

Regarding the movement of blood along abnormally located channels during different types TMS, it looks like this:

Corrected TMS. Abnormal blood circulation is somewhat modified. Namely, depleted venous blood is flowing through the pulmonary artery, and arterial blood moves through the aorta. In this case, the pathology will look more or less pronounced if the baby also has concomitant heart defects such as dysplasia of the interventricular or atrial septum, valve insufficiency, etc.
Against the background of simple TMS, blood flow from the right chamber of the heart moves into the aorta and then further into the systemic circle. Having passed the trajectory, the blood returns to the same cardiac chamber. Blood from the left ventricle enters the pulmonary artery and then further into the pulmonary circle. Later blood still returns to the left chamber of the heart. In this situation, oddly enough, additional heart defects (septal dysplasia, valve insufficiency, etc.) can save the situation. Against the background of such defects, the blood, although not enough, still mixes. If the baby does not have such defects, the baby dies a few hours after birth.

Symptoms

In newborns with complete TMS, the following signs and symptoms of pathology are noted immediately after birth:

cyanosis (blueness of the upper body);
enlarged liver and heart;
swelling of the body;
change in the shape of the phalanges of the fingers;
tachycardia and heart murmurs;
shortness of breath even at rest;
In rare cases, ascites is detected.

Corrected TMS in a patient may be characterized by the following signs and symptoms:

obvious developmental delay;
frequent pneumonia;
paroxysmal tachycardia plus heart murmurs;
atrioventricular block.

Diagnostics

To put accurate diagnosis, specialists use certain research methods. Early diagnosis of transposition of the great vessels includes the following techniques:

Initial examination of the patient and listening to the heart.
ECG to detect heart sounds and conduction of electrical impulses in the myocardium.
Echocardiography (ultrasound). Allows the doctor to assess the location of chambers and vessels, as well as determine their functionality.
Catheterization. Used to assess valve function and pressure in both ventricles.
Radiography. Makes it possible to accurately assess heart parameters and locate the pulmonary trunk.
CT or MRI of the heart. In this case, the doctor receives a complete three-dimensional image of the organ.
Angiography. Here the location of all heart vessels and their performance are assessed.

Important: if a baby’s heart defect is diagnosed in a pregnant woman while she is still pregnant, the woman is offered an artificial termination of pregnancy. If a woman insists on further gestation and birth of the fetus, then the pregnant woman is transferred to a special maternity center, which has everything necessary equipment for immediate diagnosis and possibly surgery immediately after birth.

Treatment

Transposition pathology is treated exclusively operationally. And even then only a corrected form of the defect or a form in which the oval window is not closed (simple). Today, there are several types of surgical interventions, all of which are quite effective if performed in a timely manner. All types of operations can be divided into two types:

Corrective. During the intervention, the doctor completely copes with the anomaly, eliminating it by suturing the aorta and pulmonary artery. The first connects to the left heart chamber, the second to the right.
Palliative. In this case, the purpose of the operation is to significantly improve the functioning of the pulmonary circulation. To do this, an artificial window-tunnel is formed in the atrium zone. After such an operation, the right chamber of the heart will direct blood to the lungs and further into the systemic circulation.

These are mainly used palliative operations:

Closed atrial balloon septostomy. It is indicated only for babies in the first month of life from birth, since their atrial septum remains elastic, which allows it to be ruptured by a balloon quite easily. Later, the septum thickens, making it difficult for the surgeon to perform the procedure using a catheter balloon.
Operation Park-Rushkind. Its greatest effectiveness is observed if the patient is 2 or more months old. Here, a special catheter with a thin blade is used to create a hole in the atrial septum. Using a blade, a cut is made in the septum and then the hole is inflated using a balloon.
Blalock-Hanlon operation. It is used if the first two types of interventions are ineffective.

The types of operations that can be used to correct hemodynamics include the following:

Operation Jaten. Here the surgeon performs anatomical displacement of all vascular main tracks(arteries) and at the same time in parallel swaps the mouths of the coronary arteries at the pulmonary trunk.
Mustard's operation and Senning's operation. Here the doctor uses special patches that are installed after effectively cutting the septum. Such patches change the direction of blood flow according to the anatomical norm. That is, now blood will flow from the pulmonary trunk into the right chamber, and from the vena cava into the left ventricle.

Important: The effectiveness of corrective operations is approximately 80–90%. Only 10% of patients who undergo surgery still die. Survivors develop complications such as narrowing of the lumen of the mouths of the pulmonary or vena cava (gradual) or.

Forecast

As for the prognosis for TMS, with complete transposition of the great vessels, only 20% of babies have a chance of survival. Approximately 50% of children with this defect die before 2 months. Another 60% may not even survive 1 year.

With simple transposition of the great vessels, almost 70% of children have a chance of life if the operation is performed in a timely manner. The effectiveness of the operation is almost 90%.

Corrected TMS can also be corrected 96% of the time with surgery.

Important: all patients diagnosed with TMS and who have undergone surgery receive disability and are under the supervision of a cardiologist for life in an outpatient (day) hospital. Physical activity is contraindicated for life.

Prevention

Preventative measures for TMS should only be taken by a woman who is planning a pregnancy or is already pregnant. So, if the expectant mother has chronic diseases(diabetes mellitus, etc.), it is advisable to first consult with an endocrinologist and gynecologist about the risk of developing fetal abnormalities.

A pregnant woman should protect herself from viral infections and eat a properly balanced diet so that the body receives required amount vitamins and minerals for the fetus and mother. It is also advisable for a pregnant woman to avoid exposure to radiation and unauthorized use of any medications. In addition, it is extremely important to stop smoking and drinking alcohol.

It is worth understanding that TMS is most often a heart defect incompatible with life. Therefore, if even at the stage of pregnancy a pathology in the baby was identified, then, based on the conclusion of specialists, it is necessary to hospitalize the mother for further childbirth in a specialized perinatal center, where the baby will receive the necessary prompt assistance immediately after birth. If already in the maternity hospital a woman notices unusual symptoms (blueness of the baby’s body), then it is important to insist on thorough examination baby and undergoing emergency surgery. Only this can save the life of a newborn and relatively cure him.

When anatomically proper development The aorta communicates with the left ventricle and distributes oxygenated blood throughout the systemic circulation. And the pulmonary trunk branches off from the right ventricle and delivers blood to the lungs, where it is enriched with oxygen and returns to the left atrium. The oxygenated blood then enters the left ventricle.

However, under the influence of a number of unfavorable factors cardiogenesis may occur incorrectly, and the fetus will develop such as complete transposition of the great vessels (TMS). With this anomaly, the aorta and pulmonary artery change places - the aorta branches off from the right ventricle, and the pulmonary artery from the left ventricle. As a result, blood not enriched with oxygen enters the systemic circulation, and oxygenated blood is again delivered to the pulmonary circulation (i.e., to the lungs). In this way, the blood circulation circles are separated, and they represent two closed rings that do not communicate with each other in any way.

The hemodynamic disturbance that occurs during such TMS is incompatible with life, but often this anomaly is combined with a compensating presence in the interatrial septum. Thanks to this, the two circles can communicate with each other through this shunt, and at least a slight mixing of venous and arterial blood occurs. However, such slightly oxygenated blood cannot fully saturate the body. If the heart also has a defect in the interventricular septum, then the situation is compensated further, but such enrichment of the blood with oxygen is not enough for normal functioning body.

A child born with such a congenital defect quickly falls into critical condition. manifests itself already in the first hours of life, and in the absence immediate assistance the newborn dies.

Complete TMS is a critical blue type heart defect that is incompatible with life and always requires immediate cardio surgical treatment. In the presence of an open oval window and a defect interatrial septum The operation may be delayed, but it should be performed in the first weeks of the child's life.

This congenital defect is one of the most common anomalies of the heart and blood vessels. It, along with the tetralogy of Fallot, is open oval window, defect interventricular septum and is one of the “big five” cardiac anomalies. According to statistics, TMS develops 3 times more often in male fetuses and accounts for 7-15% of all birth defects.

In children with corrected TMS, the location of the ventricles, rather than the arteries, changes. With this type of defect deoxygenated blood appears in the left ventricle, and oxygenated in the right. However, from the right ventricle it enters the aorta and enters the systemic circulation. Such hemodynamics are also atypical, but blood circulation still occurs. As a rule, this type of anomaly does not affect the condition born child and does not pose a threat to his life. Subsequently, such children may experience some developmental delay, since the functionality of the right ventricle is lower than that of the left, and it cannot fully cope with ensuring normal blood supply to the systemic circulation.

In this article we will introduce you to possible reasons, varieties, symptoms, methods of diagnosis and correction of transposition of the great vessels. This information will help you make general idea about the essence of this dangerous congenital heart defect of the blue type and the principles of its treatment.

Bad habits pregnant women significantly increase the risk of developing congenital heart defects in the fetus.

Like all other congenital heart defects, TMC develops during prenatal period under the influence of the following unfavorable factors:

heredity;
unfavorable environment;
taking teratogenic drugs;
viral and bacterial infections(measles, mumps, chicken pox, rubella, ARVI, syphilis, etc.);
toxicosis;
diseases of the endocrine system (diabetes mellitus);
the age of the pregnant woman is over 35-40 years;
polyhypovitaminosis during pregnancy;
contact of the expectant mother with toxic substances;
bad habits of a pregnant woman.

An abnormal location of the great vessels is formed in the 2nd month of embryogenesis. The mechanism of formation of this defect has not yet been sufficiently studied. Previously it was assumed that the defect is formed due to improper bending of the aortic-pulmonary septum. Later, scientists began to assume that transposition is formed due to the fact that when branching truncus arteriosus abnormal growth of the subpulmonary and subaortic conus occurs. As a result, the pulmonary valve is located above the left ventricle, and the aortic valve is located above the right ventricle.

Classification

Depending on the accompanying defects that perform the role of shunts compensating for hemodynamics during TMS, a number of variants of this anomaly of the heart and blood vessels are distinguished:

a defect accompanied by a sufficient volume of pulmonary blood flow and hypervolemia and combined with a patent foramen ovale (or simple TMS), a ventricular septal defect or patent ductus arteriosus and the presence of additional shunts;
a defect accompanied by insufficient pulmonary blood flow and combined with a ventricular septal defect and stenosis of the outflow tract (complex TMS) or with a narrowing of the outflow tract of the left ventricle.

In approximately 90% of patients, TMS is combined with hypervolemia of the pulmonary circulation. In addition, 80% of patients have one or more additional compensating shunts.

The most favorable option for TMS is in cases where, due to defects of the interatrial and interventricular septa, sufficient mixing of arterial and venous blood is ensured, and moderate narrowing of the pulmonary artery prevents the onset of significant pulmonary hypervolemia.

Normally, the aorta and pulmonary trunk are in a crossed state. During transposition, these vessels are located parallel. Depending on their relative position, the following TMS options are distinguished:

D-option – aorta to the right of the pulmonary trunk (in 60% of cases);
L-variant – aorta to the left of the pulmonary trunk (in 40% of cases).

Symptoms

During intrauterine development, TMS hardly manifests itself in any way, since during fetal circulation the pulmonary circulation does not yet function, and blood flow occurs through the oval window and the patent ductus arteriosus. Usually children with such a heart defect are born in normal timing, with sufficient or slightly excess weight.

After the birth of a child, its viability is completely determined by the presence of additional communications that ensure the mixing of arterial and venous blood. In the absence of such compensating shunts - a patent foramen ovale, a ventricular septal defect or a patent ductus arteriosus - the newborn dies after birth.

Typically, TMS can be detected immediately after birth. Exceptions are cases of corrected transposition - the child develops normally, and the anomaly appears a little later.

After birth, the newborn develops the following symptoms:

total cyanosis;
rapid pulse.

If this anomaly is combined with coarctation of the aorta and patent ductus arteriosus, then the child has differentiated cyanosis, manifested by greater cyanosis of the upper body.

Later in children with TMS it progresses (the size of the heart and liver increases, ascites develops less often and edema appears). Initially, the child’s body weight is normal or slightly excessive, but later (by 1-3 months of life) malnutrition develops due to cardiac insufficiency and hypoxemia. Such children often suffer from acute respiratory viral infections and pneumonia, and are lagging behind in physical and mental development.

When examining a child, a doctor may identify the following symptoms:

wheezing in the lungs;
expanded chest;
unsplit loud II tone;
noises of accompanying anomalies;
rapid pulse;
heart hump;
deformation of fingers like “drum sticks”;
liver enlargement.

With corrected TMS, which is not accompanied by additional congenital anomalies of the heart, the defect can be asymptomatic for a long time. The child develops normally, and complaints appear only when the right ventricle ceases to cope with the systemic circulation sufficient quantity oxygenated blood. When examined by a cardiologist, such patients are diagnosed with heart murmurs and atrioventricular block. If corrected TMS is combined with other congenital defects, then the patient develops complaints characteristic of the existing anomalies of heart development.

Diagnostics

In almost 100% of cases, this heart defect is diagnosed immediately after the birth of a child, in the maternity hospital.

Most often, TMS is detected in the maternity hospital. When examining the child, the doctor discovers a pronounced medially displaced cardiac impulse, cardiac hyperactivity, cyanosis and dilatation chest. When listening to the sounds, an increase in both tones, the presence of systolic murmur and murmurs characteristic of concomitant cardiac defects are revealed.

For a detailed examination of a child with TMS, following methods diagnostics:

chest x-ray;
catheterization of cardiac cavities;
(aorto-, atrio-, ventriculo- and coronary angiography).

Based on the results instrumental studies heart, the cardiac surgeon draws up a plan for further surgical correction of the anomaly.

Treatment

With complete TMS, all children undergo emergency palliative operations in the first days of life, aimed at creating a defect between the pulmonary and systemic circulation or expanding it. Before such interventions, the child is prescribed a drug that promotes non-union ductus arteriosus– prostaglandin E1. This approach allows for mixing of venous and arterial blood and ensures the child’s viability. A contraindication to performing such operations is the development of irreversible pulmonary hypertension.

Depending on the clinical case one of the methods of such palliative operations is selected:

balloon atrioseptostomy (endovascular Park-Rushkind technique);
open atrioseptectomy (resection of the interatrial septum using the Blalock-Hanlon technique).

Such interventions are performed to eliminate life-threatening hemodynamic disorders and are preparation for the necessary cardiac surgical correction.

To eliminate hemodynamic disturbances that occur during TMS, following operations:

According to Senning's method. The cardiac surgeon, using special patches, redraws the cavities of the atria so that blood from the pulmonary veins begins to flow into the right atrium, and from the vena cava into the left.
According to Mustard's method. After opening the right atrium, the surgeon excises most of the interatrial septum. The doctor cuts out a patch in the shape of pants from a piece of pericardium and sews it in such a way that blood from the pulmonary veins flows into the right atrium, and from the vena cava into the left.

To anatomically correct the incorrect location of the great vessels during transposition, the following arterial switching operations can be performed:

Crossing and orthotopic replantation of the great vessels, ligation of the PDA (according to Zatena). The pulmonary artery and aorta cross and move to their respective ventricles. In addition, the vessels anastomose their distal sections with the proximal segments of each other. Next, the surgeon performs the transplant coronary arteries into the neoaorta.
Elimination of pulmonary artery stenosis and plastic surgery of ventricular septal defect (according to Rastelli). Such operations are performed when transposition is combined with a ventricular septal defect and pulmonary artery stenosis. The ventricular septal defect is closed with a patch of pericardium or synthetic material. Pulmonary artery stenosis is eliminated by closing its mouth and implanting a vascular graft that provides communication between the right ventricle and the pulmonary trunk. In addition, new blood outflow pathways are formed. Blood flows from the right ventricle to the pulmonary artery through the created extracardiac conduit, and from the left ventricle to the aorta through the intracardial tunnel.
Arterial switching and plastic surgery of the interventricular septum. During the intervention, the pulmonary artery is cut off and reimplanted into the right ventricle, and the aorta into the left ventricle. The coronary arteries are sutured to the aorta, and the ventricular septal defect is closed with a synthetic or pericardial patch.

Typically, such operations are performed before 2 weeks of a child’s life. Sometimes their implementation is delayed up to 2-3 months.

Each of the above methods of anatomical TMS correction There are indications, contraindications, pros and cons. The tactics of arterial switching are selected depending on the clinical case.

After cardiac surgical correction, patients are recommended to undergo further lifelong monitoring by a cardiac surgeon. Parents are advised to ensure that their child follows a gentle regimen:

exclusion of severe physical activity and excessive activity;
good sleep;
proper organization of the daily routine;
proper nutrition;
prophylactic use of antibiotics before dental or surgical procedures to prevent infective endocarditis;
regular observation by a doctor and compliance with his prescriptions.

In adulthood, the patient must follow the same recommendations and restrictions.

Forecast

Newborns with transposition of the great vessels require urgent surgical intervention.

In the absence of timely cardiac surgical treatment, the prognosis for the outcome of TMS is always unfavorable. According to statistics, about 50% of children die during the first month of life, and more than 2/3 of children do not survive until the age of 1 year due to severe hypoxia, increasing acidosis and heart failure.

The prognosis after cardiac surgery becomes more favorable. With complex defects, positive long-term results are observed in approximately 70% of patients, with simpler ones - in 85-90%. Regular monitoring by a cardiac surgeon is of no small importance in the outcome of such cases. After corrective operations, patients may develop long-term complications: stenosis, thrombosis and calcification of conduits, heart failure, etc.

Transposition of the great vessels is one of the most dangerous vices heart and can only be eliminated surgically. The timeliness of cardiac surgery is of no small importance for its favorable outcome. Such operations are carried out up to 2 weeks of the child’s life, and only in some cases they can be delayed up to 2-3 months. It is desirable that such a developmental anomaly be detected before the baby is born, and that pregnancy and childbirth are planned taking into account the presence of this dangerous congenital heart defect in the unborn child.

Transposition of the great vessels (hereinafter referred to as TMS, TMA) in newborns is of two types. The first is an anomaly in which the aorta begins from the anatomically right ventricle, and the pulmonary artery (hereinafter PA) begins from the anatomically left ventricle. The defect is characterized only by abnormal spatial relationships of the great vessels. The atria, atrioventricular valves, and ventricles are formed and positioned correctly.

The second, more rare case is when, simultaneously with the “confused” arteries, the atria, ventricles and valves are also out of place. This sounds worse, but in fact it is a much more favorable picture, because with such a TMA hemodynamics are practically not impaired.

Let's consider both options and talk about the diagnosis, anatomy, the danger of these defects, as well as when and how exactly they are treated.

Corrected transposition of the great vessels (ICD-10 code - Q20.5) is a congenital heart defect that is manifested by inconsistency (discordance) between the atria and ventricles, as well as the ventricles and pericardial arteries.

Despite the inconsistent communication between the chambers, the blood flow is physiological in nature - arterial blood enters the aorta, and venous blood enters the pulmonary trunk. The right atrium is connected to the ventricle through a valve, which is anatomically mitral, and the right ventricle has the structure of the left. From it, blood enters the lungs through the pulmonary artery.

From the lungs, the pulmonary veins connect to the left atrium. Between it and the ventricle there is a valve that repeats the structure of the tricuspid, and the ventricle itself is anatomically represented as right, not left. From it arterial blood enters the aorta.

Differences from the uncorrected form:

There is no isolation of the blood circulation from each other;
The aorta and pulmonary trunk do not intersect, but run parallel;
Simultaneous crossing of the ventricles is observed;
Characteristic disturbances in the structure of conductive fibers and the development in patients various types arrhythmias.

The incidence is 0.5% of all birth defects.

Hemodynamics

An isolated defect does not lead to hemodynamic impairment, since organs receive oxygen in the right amount, A venous drainage has no obstacles. The essence of the defect is expressed not in the reverse structure of the heart valves and ventricles, but in the incorrect distribution of intracardiac load.

The right ventricle, which is anatomically left, begins to work with redoubled force. At the same time, the coronary arteries are not able to provide adequate blood flow (the right ventricular artery is much smaller than the left), which leads to its gradual ischemia and the development of angina.

The parallel development of mitral valve prolapse, which is anatomically tricuspid and not adapted to withstand high pressure, is also characteristic.

Is it dangerous for newborns?

Since separation of the blood circulation does not occur, the disease in most cases is diagnosed on later(in the first and second decades of life). Average age detection – 12.5 years. In some patients, the defect remains undetected throughout their lives.

The condition of patients worsens with the development of arrhythmia and cardiac ischemia. Arrhythmias accompany the disease in 60% of cases (paroxysmal tachycardia, atrial fibrillation, blockades) and are often the first reason to see a doctor. In another group of patients, due to the fact that the right ventricle does the work of the left and experiences great overload, heart pain occurs like angina pectoris.

The timing will depend on the presence of concomitant defects and complications. Patients with additional defects (septal defects) are characterized by vivid symptoms and early detection of the disease; treatment is required in the first 28 days of life. In other patients, due to satisfactory general condition and a small number of complaints, treatment is carried out as planned.

Treatment is different, since the corrected form has its own characteristics and is accompanied by arrhythmia and ischemic painful attacks. The corrected form of therapy is complemented by the treatment of these complications.

What is an uncorrected (full) TMA?

Complete transposition of the great vessels (ICD-10 code - Q20.3)- This is a critical blue-type congenital heart disease, which is characterized by inverse connection between the ventricles and the pericardial arteries.

With a defect, complete delineation of the blood circulation occurs due to the inverse arrangement of large arterial trunks. The right ventricle is connected to the aorta, the left - to the pulmonary artery. Venous blood, bypassing the lungs, enters the internal organs from the right ventricle and returns through the vena cava. The lungs receive arterial blood from the left ventricle, which returns to it, bypassing organs and tissues. Venous blood does not become arterial, while arterial blood gradually becomes oversaturated with oxygen.

Synonyms: uncorrected TMS, cyanotic TMS, transposition main arteries, TMA.

Depending on the combination with other anomalies, TMS is distinguished, having:

intact septum between the ventricles;
(hereinafter referred to as VSD);
combination and VSD.

Frequency of occurrence of the defect: 5-7% of all congenital heart defects. It happens 3 times more often in boys than in girls. This CHD was first described in 1797 by M. Baillie, and the definition was first given by Abbott.

Anatomy

The aorta is located in front and most often to the right of the pulmonary artery and begins from the right ventricle. The PA is located behind the aorta, starting from the left ventricle. Both main vessels run parallel to each other (normally they cross).

There is often an anomalous origin of the coronary vessels. The vena cava approach the right atrium, the pulmonary veins approach the left (as normal).

Hemodynamics

The blood circulation circles are separated:

Venous blood flows from the right ventricle into the aorta. It circulates through the systemic circulation and comes through the vena cava to the right atrium, from where it again enters the right ventricle.
Arterial blood comes from the left ventricle to the PA. It circulates in the pulmonary circulation and through the pulmonary veins through the left atrium again enters the left ventricle. That is, oxygenated blood constantly circulates in the lungs.

Mixing of blood from 2 circles of circulation and, as a consequence, compatibility with life with such hemodynamics is possible only if there are messages at the level of any parts of the heart or extracardially (outside the heart).

This explains why possible fetal survival in utero. During this period, there are temporary structural features: the oval window between the atria, the ductus arteriosus between the PA and the aorta, and gas exchange takes place in the placenta. Therefore, the existence of the defect does not greatly affect the development of the fetus.

After birth, the baby loses its placenta, and the fetal (only the fetus has) communications are closed. And then several options for the development of pathology are possible:

The movement of blood at the level of any communication always goes in 2 directions, otherwise one of the circles would be completely empty.

Useful video about hemodynamics during transposition of the great arteries:

How dangerous is this?

This defect is critical and incompatible with life. After birth, the child develops deep hypoxia, accompanied by overflow of the small circle. Most newborns die in the first or second month.

Life expectancy increases slightly if the defect is accompanied by the presence of a hole in the heart septum - this allows the blood circulation to communicate with each other. Such a defect is necessary for the continuation of life during the period of preparation for surgery, but if left untreated, the defect quickly leads to heart failure.

Natural course

TMS of any type - critical condition requiring early intervention childhood . In the absence of surgery 30% of children die within the first week, 50% in the first month, 70% within six months, 90% before the age of 1 year. Survival is determined by the type of defect.

Causes of death: heart failure, hypoxia, acidosis, concomitant pathology (ARVI, pneumonia, sepsis).

When is treatment required?

The timing of treatment will depend on whether the child has a hole between the chambers of the heart. If a septal defect is present, surgery is performed within the first 28 days after birth. If there is no defect, surgery is planned in the first week of life. In some cases (if there is a highly specialized hospital and a surgeon narrow specialization) surgery can be performed on the fetus.

Causes and risk factors

The exact reason has not been established. Genetic inheritance is suspected, but the gene responsible has not yet been discovered. Sometimes the reason is spontaneous mutation, when the pregnant woman was not exposed to any external influences such as x-rays, infectious diseases, or taking medications.

Risk factors:

pregnant women over 40 years of age;
alcohol abuse during pregnancy;
infections during pregnancy;
diabetes;
hereditary burden.

The majority of patients are boys with large birth weights. TMA occurs most often in children with chromosomal abnormalities and Down syndrome. Less common are concomitant defects such as communication between the right atrium and the left ventricle.

Symptoms in children and adults

External signs:

Cyanosis of the skin and mucous membranes, which appears immediately or shortly after birth.
This sign is observed in 100% of patients, which is why the defect is also called “blue”.

The severity of cyanosis depends on the size of the shunt opening. When the baby cries, the cyanosis turns purple.
Shortness of breath in 100% of patients.
Normal or increased birth weight. However, by the age of 1-3 months, malnutrition develops due to difficulties in feeding such children, which are caused by hypoxemia and heart failure.
Delayed motor development.
Often mental retardation.
Repeated acute respiratory viral infections, pneumonia.

Signs revealed during physical examination:

wheezing in the lungs;
II tone is loud, unsplit;
in the absence of concomitant defects, no murmurs are heard in the heart area;
when VSD is present, audible systolic murmur medium strength along the lower half of the left edge of the sternum, caused by the discharge of blood through the VSD;
in the presence of PA stenosis, there is a systolic ejection murmur (at the base of the heart, quiet);
tachycardia;
increase in liver size.

Diagnostics

Laboratory data: blood gas examination revealed severe arterial hypoxemia. Data from instrumental methods are presented below.

Differential diagnosis is carried out with other blue-type congenital heart defects.

How is it detected in the fetus: Ultrasound and ECG

Method	Determination time	results
Determining the thickness of the collar space	12-14 weeks (1st trimester)	Thickness more than 3.5 mm
First ultrasound screening	1st trimester	Disturbance of the embryonic anlage of the heart and large vessels
Second ultrasound screening	2nd trimester	Formed transposition of blood vessels, fetal growth restriction
Color Doppler mapping	2nd trimester	Disconnection of blood circulation, transposition of blood vessels
Ultrasound of the heart (fetal echocardiography)	2nd trimester	Separation of blood circulation, transposition of blood vessels, “egg-shaped” heart
Indirect electrocardiography	2nd trimester	Bias electrical axis heart to the left, signs of heart block

If the diagnosis is confirmed, a medical consultation is held. Further tactics:

Pregnant gets comprehensive information about the defect, treatment prospects and possible risks of surgery;
At the time of childbirth, a woman is hospitalized in a maternity hospital with intensive care and cardiovascular surgery departments;
After delivery, surgery is performed.

Treatment

The disease always manifests itself during the neonatal period. The rate of deterioration of the child’s condition depends on the presence and size of accompanying defects that determine the communication between the two circles of circulation. Treatment is surgical only. When making a diagnosis, the indications are absolute.

Preoperative preparation

Obtaining data on arterial blood oxygen saturation and its pH.
Measures to correct metabolic acidosis and hypoglycemia.
Intravenous infusion of prostaglandin E1 preparations. This prevents the ductus arteriosus from closing, and the possibility of mixing blood remains. The measure is only a short-term alternative to the Rashkind procedure.
For severe hypoxia - oxygen therapy.
Assessment of the condition of the kidneys, liver, intestines and brain.

Surgical methods can be divided into corrective and palliative.

Palliative operations

Palliative operations are intended to:

reduce hypoxemia by improving blood exchange between the right and left parts of the heart;
create good conditions for the functioning of the pulmonary circulation;
be technically simple and not create obstacles to corrective surgery in the future.

Various methods for expanding or creating an ASD can satisfy these requirements. Of them the most common are the Rashkind operation and the Park method.

In cases where the child has an ASD of sufficient size, correction of the defect can be performed without palliative interventions. In other cases, corrective surgery is usually preceded by palliative interventions.

Operation Rashkind

In patients without ASD or VSD, surgery should be performed immediately upon admission to the cardiac surgery center. The increase in blood oxygenation obtained with this procedure gives freedom to choose the timing of corrective surgery within 7-20 days after birth.

Progress of the operation:

A folded balloon is inserted through the femoral and inferior vena cava into the right atrium.
It is pushed through the foramen ovale into the left atrium, where it fills with fluid. X-ray contrast agent and sharply returns in a straightened form to the right side under X-ray or echoscopic control. In this case, the valve of the oval hole is torn off.

The advantage of the procedure is that there is no dissection of the chest, which usually causes the development of adhesions in this area, and this complicates the subsequent corrective surgery (thoracotomy and isolation of the heart are difficult).

Park equipment

If the child is more than 30 days old the proper effect of the Rashkind operation is often not achieved due to the fact that the valve of the oval window is tightly fixed to the septum, as well as due to the greater strength of the interatrial septum. In these cases, the Park technique is used.

Using a blade built into the end of the catheter, the septum between the atria is cut, and then dilation is performed using a balloon.

Complete arterial correction

Corrective operations should radically correct impaired hemodynamics and eliminate compensating and associated defects. The main such interventions include arterial switching and intraatrial correction.

Arterial switching

The bottom line: true anatomical correction of TMS. Optimal time implementation: first month of life.

Progress of the operation:

After putting the patient under anesthesia and dissecting the chest, they begin artificial circulation, which simultaneously cools the blood.
When the temperature decreases, the metabolism slows down, and this protects the body from postoperative complications. The aorta and PA are cut.
Separated from the aorta coronary vessels and connect to the beginning of the PA, which will then become the beginning of a new aorta. The severed aorta is sutured here. A tube is then created from a piece of the patient's pericardium, which is sewn into the new LA and repairs it.

Main complications: supravalvular aortic stenosis, PA; insufficiency of the aortic valve and/or pulmonary valve; heart rhythm disturbances.

Methods of intra-atrial correction (Mustard and Senning)

They long time were the only ways surgical treatment of transposition of the great arteries. Now these operations are used when it is not possible to perform a complete anatomical correction of the defect.

The bottom line: correction of hemodynamics, the defect itself is not anatomically corrected.

Progress of the operation: the right atrium is dissected, the interatrial septum is completely removed and patches from the patient’s tissue (part of the atrium wall, pericardium) are sewn inside the resulting cavity. As a result, blood flows through the vena cava into the left ventricle, pulmonary artery and lungs, and from the pulmonary veins into the right ventricle, aorta and systemic circle.

Additional corrective surgeries: VSD repair, correction of PA stenosis.

Useful video about TMA correction:

Prognosis and mortality after surgery, duration and quality of life

The prognosis after surgery for both defects is relatively favorable. Patients with complete transposition experience slower physical development, stunted growth, decreased immunity, and a tendency to infectious diseases despite the therapy.

Life expectancy, depending on the usefulness of the operation, may not be reduced, but more often there is a decrease in it by 10-15 years. Patients who live into adulthood and old age adhere to individual medical recommendations for life.

In people with a corrected form, life expectancy is not changed. Patients from this group live to adulthood and old age (70 years or more). The quality of life changes slightly - those operated on are registered with a cardiologist and undergo courses of treatment for arrhythmia, angina pectoris and other concomitant diseases.

Mortality during operations:

Rashkind operation – 9%;
Operation Park – 13%;
Operation Mustard – 25%;
Arterial switching - 10%.

Immediate and long-term consequences of correction

Immediate consequences:

Damage to the coronary arteries;
Myocardial fiber ruptures and small focal infarctions;
Arrhythmia.

Long-term consequences:

Complete atrioventricular block;
Acute and chronic heart failure;
Atrial paroxysmal tachycardia;
Ventricular flutter and fibrillation;
Developmental delay;
Prolapse of the mitral valves.

Most common reasons negative consequences are:

Traumatic injuries of coronary vessels;
Incomplete elimination concomitant pathology- septal defect, mitral insufficiency;
Rupture of conductive nerve fibers (bundles of His, Purkinje fibers).

Observation

Operated patients are monitored for life. Interval - 6-12 months. The goal is timely detection of complications. In the first six months after surgery or if complications arise in long term prevention of bacterial endocarditis is carried out.

Transposition of the great vessels is characterized by rapid development severe complications, critically disrupting work of cardio-vascular system. Without treatment, children die early age. That's why it is necessary to take urgent conservative and surgical measures to correct TMS taking into account its type.

At 27 weeks of pregnancy, I had an ultrasound and echocardiography of the fetus and discovered a heart defect in the unborn baby. To say that it was a SHOCK is simply an understatement! Since there was no question of terminating the pregnancy, the doctors “reassured” my husband and me that if favorable outcome surgery (and you can’t do without it), the child will be able to live quite fully.

For reference: Transposition of the great vessels (TMS) is a congenital heart disease characterized by discordance of the ventricular-arterial connection with concordance of the connection of the remaining segments of the heart. In other words, the aorta arises from the morphologically right ventricle, and the pulmonary trunk - from the morphologically left one. Statistical data 7–15% of all congenital heart disease 9.9% of congenital heart disease diagnosed in infancy The ratio of male to female at birth is 3:1.
If normally the systemic and pulmonary circulations are connected in series, then with TMS they function in parallel, being completely separated. That's why required condition even for a short life - the presence of communications between the large and small circles of blood circulation in the form of naturally existing or artificially created defects. In this case, blood is discharged during TMS in both directions.

Only now, when Andryushka is almost six months old, can I more or less calmly talk about what happened to us after that. A sea of tears about why and for what, thoughts about what can and should be done, patience, patience, waiting, hope and faith in the best...

Before giving birth, there was no need to worry, as long as the lungs were not involved, nothing threatened the child’s life, but from the moment of birth, minutes counted, or at best, hours. I had to give birth at the Samara Regional Clinical Cardiology Dispensary. The birth went well, I saw the baby, only here I found out that we were having a boy (before that, during the ultrasound, we were least interested in gender). And they immediately took him away... they didn’t put him to their chest, they didn’t let me hug him, or even touch him... I felt creepy and lonely, it was too early to rejoice, but I did everything I could. Now he is in the hands of the Lord God and heart surgeons. My baby, so defenseless, tiny, dear and very much needed!

The first part of this video is about us. Similarly, on the 6th day after birth, Andrei underwent surgery. Just not in Moscow, in Samara. Huge gratitude and bow to the ground to cardiac surgeons, anesthesiologists, resuscitators and nurses, everyone whose kind heart and caring hands gave my son a chance to continue his life.

The operation lasted more than six hours, it was necessary to swap vessels, coronary arteries, and the thickness of the blood vessels of a newborn child is unimaginably small. This is artificial blood circulation, blood transfusion, artificial respiration, opening of the sternum... Mom and I sat in the corridor, waiting.
The doctor returned and said that the operation was completed, there was bleeding, but they managed to cope with it, the baby’s heart began to beat, and now we need to wait and hope that the body will recover, that there will be no complications.

For three weeks my son was in intensive care, he could be visited twice a day, I came and brought expressed milk, which a few days later they began to give him through a tube, a little more every day, they gradually turned off the ventilator (artificial lung ventilation), and canceled drugs, antibiotics, they removed and removed various tubes from my baby’s body...

Only when his condition no longer required intensive care was I allowed to go into the ward with him.
He learned to suck, at first he had to pour milk in a trickle through the nipple, he didn’t have the strength to get food on his own... but we defended breastfeeding!!! A week later he was suckling on his own and gaining weight.

At the age of one month we were already at home. Finally, brother and sister were able to see Andryushka, whose mother and father had been missing for so long, so beloved and long-awaited, so small and nice. They were very happy!

4 months after the operation, you can no longer take the baby by the armpits or arms, so as not to damage the sternum, which is held together with wires. Now on his chest x-ray there will always be delays... and there is a scar on his chest, but it is getting smaller and lighter, thin, cosmetic, and a few more scars from all sorts of drains, probes, defibrillators on his stomach and side... Memory of how life began.

Constant monitoring, drug powders, ECG, visits to a cardiac surgeon, not everything was so rosy... Two months later we were told that one of the vessels began to narrow at the site of stitching, which could lead to an increase in pressure in the heart, from there swelling in the lungs , liver, kidneys, etc. along the chain. Turning up in two months, again painful waiting and hope that everything will work out. I really didn’t want to go through surgery again and go through all these circles: intensive care, anesthesia, opening the sternum,... A terrible dream...

But the next visit pleased both us and the doctors. Hemodynamics showed improvements, stable improvements. We were taken off the medicine. The first time we took our grown-up baby under our arms, and not like a crystal vase. Now you can rejoice that all the bad things are behind you.

Soon Andryushka is six months old, he is the same cheerful, cheerful and friendly baby, happily stomping his feet on the carpet, cooing and nice, like his peers, whose lives had a different beginning.
I thank you, Almighty, myself and everyone for this important, difficult, but surmountable life lesson.

My children, I love you very much!

Complete transposition of the great vessels is a severe cyanotic congenital heart defect in which the aorta arises from the right ventricle and is located anterior to the posterior trunk of the pulmonary artery; the latter departs from the left ventricle and carries oxygenated blood; there are properly formed atrioventricular valves and ventricles of the heart. This definition excludes the presence of a single ventricle of the heart, in which the type of location of the great vessels is not significant, and atresia of one of the atrioventricular valves, which plays a decisive role in the resulting hemodynamic disorders.

According to data from the departments of congenital heart defects in young and older children, the Institute of Cardiovascular Surgery named after A. N. Bakulev of the USSR Academy of Medical Sciences, the frequency of complete transposition of the great vessels in patients under the age of 1 month was 27%, 1-3 months - 16.7%, 36 months - 9.4%, 6-12 months - 4%, 1-2 years - 1.2%, over 2 years - 0.5%. The difference between clinical and anatomical data, as well as the difference in data obtained depending on age, is due to high mortality rate patients with this heart defect in early childhood, which leads to a decrease in the number of these patients at an older age.

This is confirmed by data from Liebman et al (1969), according to which 28.7% of infants born with complete transposition of the great vessels die within the 1st week of life, 51.6% within the 1st month and 89.3% —by the end of the 1st year of life. Average duration life, according to the same authors, depended on compensating and accompanying defects and amounted to 0.11-0.28 years for small interatrial and interventricular communications, and 0.81 years for large interatrial defects, with. large defects of the interventricular septum and structural changes pulmonary vessels - 2 years, for ventricular septal defects with pulmonary artery stenosis - 4.85 years.

Anatomy

With complete transposition of the great vessels, the hollow and pulmonary veins carry blood to the right and left atria, which, with the help of the tricuspid and mitral valves communicate with the corresponding ventricles. However, in contrast to the normal picture, the aorta arises from the right ventricle, and the trunk of the pulmonary artery from the left ventricle. The ascending aorta is always located in front and often to the right in relation to the trunk of the pulmonary artery located behind and to the left. In rare cases, the aorta lies in the midline of the body, just in front of the pulmonary trunk, and even more rarely, the aorta lies to the left of the pulmonary trunk. The course of both main vessels is parallel, and the pulmonary artery is always covered by the aorta by 1/2-1/3, less often - completely.
As a rule, there is an abnormal arrangement of the coronary arteries. In the most common option, the left coronary artery starts from the aortic sinus of Valsalva. Its trunk, in contrast to the normal course, goes anterior to the trunk of the pulmonary artery and gives rise to the anterior descending and left circumflex branches. The right coronary artery arises from the posterior aortic sinus and goes into the right atrioventricular groove. Thus, the right aortic sinus with this defect is non-coronary (Shaher, Puddu, 1966).

Due to the fact that the right ventricle, pumping blood into the aorta, works under conditions of hyperfunction aimed at overcoming high ejection resistance, a sharp hypertrophy of its myocardium is observed. Less pronounced hypertrophy of the left ventricle is due to the fact that it functions under conditions of loading with an increased volume of blood. Only the presence of pulmonary artery stenosis or irreversible morphological changes in the pulmonary vessels can lead to its sharp hypertrophy.

Life with complete transposition of the great vessels is impossible without compensating defects. A patent foramen ovale occurs in 33% of patients, a ventricular septal defect in 61%, a patent ductus arteriosus in 8.5%, and atrial septal defect in 5.7% of patients. Of the associated defects, pulmonary artery stenosis (23%) is most often observed, and it is combined with a ventricular septal defect.

Hemodynamics

Blood flow is carried out through two separate circulatory circles. In the first circle, blood flows from the right ventricle into the aorta and, having passed through the systemic circulation, returns through the vena cava and the right atrium again to the right ventricle. Consequently, the tissues and organs of the body are supplied with blood from low content oxygen. In the second circle, blood flows from the left ventricle into the pulmonary artery and, having passed through the pulmonary circulation, returns again through the pulmonary veins and the left atrium to the left ventricle. Consequently, blood circulates in the lungs with high content oxygen, which serves no useful purpose.

If during intrauterine life the presence of a defect does not significantly affect the development of the fetus, then immediately after birth the child dies. This is due to the disconnection of the blood circulation and the impossibility of normal gas exchange as a result. Only the presence of intracardiac messages through which blood is exchanged between the circulation makes these patients viable. The discharge of blood is carried out in two directions, since its one-sided nature could lead to complete emptying one of the circles. The magnitude of this discharge from right to left represents the effective pulmonary blood flow, since it is in this volume that mixed blood reaches the pulmonary capillaries (Campbell, Bing, 1949; Shaher, 1964).

The reset mechanics are carried out in the following way. In newborns, as breathing begins, expansion occurs. vascular bed lungs and a drop in pulmonary vascular resistance below the systemic level. This results in the discharge of blood from the aorta into the pulmonary artery through the patent ductus arteriosus or bronchial arteries. Less commonly, right-to-left shunting occurs at the level of the atria. As a result, the volume of blood circulating in the pulmonary circulation and entering the left atrium increases. The mean pressure in the left atrium increases, exceeding its level in the right atrium, and this leads to a shunt of blood from left to right through the interatrial communication.

In the presence of a ventricular septal defect with low or moderately increased pulmonary vascular resistance, the discharge of blood from right to left, occurring during ventricular systole, leads to hypervolemia of the pulmonary circulation. The increasing blood flow into the left ventricle is accompanied by an increase in diastolic pressure, which exceeds its level in the right ventricle and, therefore, a left-to-right shunt occurs during ventricular diastole (Shaher, 1964).

In the presence of a ventricular septal defect with high pulmonary vascular resistance or severe pulmonary stenosis, increased systemic blood flow leads to increased right atrial pressure and right ventricular diastolic pressure. Consequently, right-to-left shunting of blood through a ventricular septal defect occurs during diastole, and left-to-right shunting occurs during systole. Thus, the direction and magnitude of blood discharge during complete transposition of the great vessels are influenced by the ratio of the resistances of the systemic and pulmonary circulation, the volume of pulmonary blood flow, and the type and magnitude of the compensating message.

Clinic

Heart disease is 2.5 times more common in boys. Immediately after birth, patients experience cyanosis, which tends to increase with increasing age. If at birth the child’s weight is often normal, then at the age of 1-3 months, as a rule, malnutrition and rickets can be noted. This is usually associated with feeding difficulties that are aggravated by heart failure. A delay in physical development leads to the fact that children begin to sit and walk later. Mental retardation is often observed.

The clinical picture of the defect is largely determined by the presence or absence of pulmonary artery stenosis. Patients without concomitant pulmonary stenosis experience dyspnea at rest, which is associated with increased pulmonary blood flow and hypoxemia. Respiratory diseases are often reported. At the age of 1 year, patients can often notice a “heart hump” and, as a rule, a positive sign of “drumsticks” on the fingers and toes. All patients have polycythemia from birth, which increases with age. The hemoglobin value can reach 23-25, the number of red blood cells - 6,000,000-8,000,000, hematocrit - 80%. Percussion reveals a sharp increase in heart size.

When listening to the heart, an accent of the second tone is determined, associated with in a loud tone closing the aortic valves, which are located close to the anterior chest wall. The presence of pulmonary hypertension also leads to an accentuation of the second tone, but it is usually poorly carried out due to rear location pulmonary valves. In patients with a patent foramen ovale, murmurs are usually absent; less often, a weak systolic murmur can be heard in the second or third intercostal space at the left edge of the sternum. Noises may not be audible even with a large ventricular septal defect accompanied by high pulmonary hypertension (Wells, 1963). With small ventricular septal defects, the systolic murmur has a louder and rougher timbre and is localized in the third - fourth intercostal space at the left edge of the sternum.

Starting from the 2-4th week of life, patients develop signs of heart failure, manifested in the form of cardiomegaly and congestive wheezing in the lungs.

The electrocardiographic picture is characterized by deviation of the electrical axis of the heart to the right, hypertrophy of the right ventricle and right atrium. In patients with a large ventricular septal defect or patent ductus arteriosus and significantly increased pulmonary blood flow, a normal electrical axis of the heart and signs of hypertrophy of both ventricles can be observed.

X-ray examination in a direct projection reveals progressive cardiomegaly. In this case, the shape of the heart resembles an egg, tilted so that its long longitudinal axis lies in an oblique direction.

The pole with the least convexity faces up and to the right, and the pole with the greatest convexity faces down and to the left (Carey and Elliott, 1964). The heart is enlarged due to the left sections being loaded with an increased volume of blood, and due to the right ventricle pumping blood into the systemic circulation. In patients with pulmonary hypertension and equal systemic and pulmonary vascular resistance, the size of the heart is increased to a lesser extent, since there is no volume overload of the left parts.

Characteristic radiological sign for a given defect, Taussig considers the increase in width vascular bundle in the left anterior oblique projection, in contrast to its narrowness in the direct projection. It should be noted that in infants aged 1-2 weeks, the pulmonary pattern is normal or slightly enhanced. At older ages, the pulmonary pattern is usually enhanced, and the degree of enhancement correlates with the degree of increase in heart size.

In patients with concomitant pulmonary artery stenosis, shortness of breath is somewhat less pronounced than in patients with increased pulmonary blood flow, and polycythemia is more pronounced. A rough systolic murmur is heard at the base of the heart. Signs of heart failure are moderate or absent. The electrocardiogram shows a deviation of the electrical axis of the heart to the right, signs of hypertrophy of the right ventricle and right atrium. Only in rare cases can one observe a deviation of the electrical axis of the heart to the left (A. A. Vishnevsky, N. K. Galankin, 1962; I. V. Matveeva, B. A. Konstantinov, 1965).

Radiologically, the severity of the pulmonary pattern depends on the severity of pulmonary artery stenosis; the heart shadow is moderately enlarged in size, but to a lesser extent than in patients of the previous subgroup, and to a greater extent than in patients with tetralogy of Fallot. This is important differential feature with the last vice.

Cardiac catheterization reveals low blood oxygen saturation levels in the right cavities of the heart and in the systemic artery, sometimes reaching 30%. In the right ventricle, high pressure equal to the systemic pressure is always recorded, and from its cavity it is often possible to pass a catheter into the ascending aorta. Absolute diagnostic value has cardiac catheterization, when pressure is measured and blood samples are taken from all cavities and great vessels. Pulmonary artery catheterization is of utmost importance. In such cases, it is possible to note a higher blood oxygen saturation in this vessel compared to the aorta and determine the degree of pulmonary hypertension, which is important when planning surgical intervention. However, such information is rarely obtained, since the catheter is inserted into the pulmonary artery using the usual methods fails.

Selective angiocardiography, performed in two projections, is the method of choice and a decisive study that allows us to establish not only the presence of transposition of the aorta and pulmonary artery, but also compensating and associated defects. When a contrast agent is introduced into the cavity of the right ventricle, its predominant entry into the aorta is observed, and with left ventriculography - into the pulmonary artery. Angiocardiograms reveal front location the ascending aorta and the posterior trunk of the pulmonary artery, which have a parallel course.

A, b - contrast agent on the left ventricle enters the posterior pulmonary artery; c, d — contrast agent fills the cavity of the right ventricle and the aorta, which occupies the anterior position

Unlike normal picture The outflow tract of the right ventricle is often directed to the right, as can be seen in the frontal projection, and the outflow tract of the left ventricle is directed posteriorly, as can be seen in the lateral projection. Aortic valves located above the level of the lungs.

The greatest diagnostic value in identifying concomitant defects is the injection of a contrast agent into the right ventricle. In such cases, the interventricular septum can be traced. The absence of contrasted blood entering the left ventricle will indirectly indicate interatrial communication. If there is a ventricular septal defect, it is sometimes possible to determine its size by passing a stream of contrasted blood through it.

A - direct projection: b - lateral projection

When a contrast agent enters the pulmonary artery from the aorta, the presence of an open ductus arteriosus is established. For precise definition localization PI severity of pulmonary artery stenosis, it is more appropriate to administer the contrast agent from the left ventricle (Yu. D. Volynsky et al., 1966; I. X. Rabkin et al., 1966). In cases where complete transposition of the great vessels is accompanied by pulmonary hypertension, the diameter of the pulmonary artery trunk, detected by angiocardiography, is always wider than the diameter of the ascending aorta, and with stenosis of the pulmonary artery, with the exception of the valve, the ratios are the opposite.

V. Ya. Bukharin, V. P. Podzolkov