Congenital heart defects

Congenital heart defects are one of the most common developmental anomalies, ranking third after anomalies of the central nervous system and the musculoskeletal system. The birth rate of children with congenital heart defects in all countries of the world ranges from 2.4 to 14.2 per 1000 newborns. The incidence of congenital heart defects among live births is 0.7-1.2 per 1000 newborns. Defects with the same frequency of occurrence are often differently represented in the nosological structure among patients admitted to cardiology departments (for example, a small atrial septal defect and Fallot's tetralogy). This is due to the varying degree of threat to the health or life of the child.

The problems of diagnostics and treatment of congenital heart defects are extremely important in pediatric cardiology. Therapists and cardiologists, as a rule, are not sufficiently familiar with this pathology due to the fact that the overwhelming majority of children by puberty undergo surgical treatment or die without receiving timely adequate care. The causes of congenital heart defects are unclear. The most vulnerable period is 3-7 weeks of pregnancy, that is, the time when the heart structures are laid down and formed. Of great importance are teratogenic environmental factors, diseases of the mother and father, infections, especially viral ones, as well as alcoholism of parents, drug use, and smoking of the mother. Many chromosomal diseases are associated with congenital heart defects.

ICD 10 code

Q20. Congenital anomalies (malformations) of the cardiac chambers and connections.

Survival factors for congenital heart defects

Anatomical and morphological severity, i.e. type of pathology. The following prognostic groups are distinguished:

• congenital heart defects with a relatively favorable outcome: patent ductus arteriosus, ventricular septal defect (VSD), atrial septal defect (ASD), pulmonary artery stenosis; with these defects, natural mortality in the first year of life is 8-11%;
• Tetralogy of Fallot, natural mortality in the first year of life is 24-36%;
• complex congenital heart defects: left ventricular hypoplasia, pulmonary atresia, common arterial trunk; natural mortality in the first year of life - from 36-52% to 73-97%.

1. The patient's age at the time of manifestation of the defect (the appearance of clinical signs of hemodynamic disturbances).
2. The presence of other (extracardiac) developmental defects increases mortality in a third of children with congenital heart disease to 90%.
3. Birth weight and prematurity.
4. The child's age at the time of correction of the defect.
5. The severity and degree of hemodynamic changes, in particular the degree of pulmonary hypertension.
6. Type and variant of cardiac surgery.

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Natural history of congenital heart defects

Without surgical treatment, congenital heart defects have different course. For example, in children aged 2-3 weeks, hypoplastic left heart syndrome or pulmonary atresia (with an intact atrial septum) are rarely observed, which is associated with high early mortality in such defects. The overall mortality rate in congenital heart defects is high. By the end of the first week, 29% of newborns die, by the first month - 42%, by the first year - 87% of children. Given the modern capabilities of cardiac surgery, it is possible to perform surgery on a newborn for almost all congenital heart defects. However, not all children with congenital heart defects need surgical treatment immediately after the pathology is detected. Surgery is not indicated for minor anatomical abnormalities (in 23% of children with suspected CHD, changes in the heart are transient) or for severe extracardiac pathology.

Taking into account the treatment tactics, patients with congenital heart defects are divided into three groups:

1. patients for whom surgery for congenital heart defects is necessary and possible (about 52%);
2. patients for whom surgery is not indicated due to minor hemodynamic disturbances (about 31%);
3. patients for whom correction of congenital heart defects is impossible, as well as those who are inoperable due to their somatic condition (about 17%).

A doctor who suspects a congenital heart defect faces the following tasks:

• identification of symptoms indicating the presence of congenital heart disease;
• conducting differential diagnostics with other diseases that have similar clinical manifestations;
• deciding on the need for urgent consultation with a specialist (cardiologist, cardiac surgeon);
• conducting pathogenetic therapy.

There are more than 90 types of congenital heart defects and many combinations of them.

Symptoms of congenital heart defects

When interviewing parents, it is necessary to clarify the time of development of the child's static functions: when he began to sit in the crib independently, to walk. It is necessary to find out how the child gained weight in the first year of life, since heart failure and hypoxia, accompanying heart defects, are accompanied by increased fatigue, "lazy" sucking and poor weight gain. Defects with hypervolemia of the pulmonary circulation can be accompanied by frequent pneumonia and bronchitis. If a defect with cyanosis is suspected, it is necessary to clarify the time of appearance of cyanosis (from birth or during the first six months of life), under what circumstances cyanosis appears, its localization. In addition, defects with cyanosis always have polycythemia, which can be accompanied by disorders of the central nervous system, such as hyperthermia, hemiparesis, paralysis.

Physique

Changes in body type occur with a few defects. Thus, coarctation of the aorta is accompanied by the formation of an "athletic" body type, with a predominance of shoulder girdle development. In most cases, congenital heart defects are characterized by decreased nutrition, often up to the 1st degree of hypotrophy, and/or hypostatura.

Symptoms such as “drumsticks” and “watch glasses” may develop, which are typical for cyanotic congenital heart defects.

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Skin

In pale type defects - paleness of the skin, in defects with cyanosis - diffuse cyanosis of the skin and visible mucous membranes, with a predominance of acrocyanosis. However, a rich "raspberry" coloration of the terminal phalanges is also characteristic of high pulmonary hypertension accompanying defects with left-right shunting of blood.

Respiratory system

Changes in the respiratory system often reflect a state of increased pulmonary blood flow and are manifested in the early stages by shortness of breath and signs of dyspnea.

Cardiovascular system

During examination, a "heart hump" is determined, located bisternally or on the left. During palpation - the presence of systolic or diastolic tremor, pathological cardiac impulse. Percussion - a change in the boundaries of relative cardiac dullness. During auscultation - in what phase of the cardiac cycle the noise is heard, its duration (what part of systole, diastole it occupies), changeability of the noise with a change in body position, conductivity of the noise.

Changes in blood pressure (BP) in congenital heart disease are rare. Thus, coarctation of the aorta is characterized by an increase in BP in the arms and a significant decrease in BP in the legs. However, such changes in BP may also occur in vascular pathology, in particular, in nonspecific aortoarteritis. In the latter case, significant asymmetry of BP in the right and left arms, in the right and left legs is possible. A decrease in BP may occur in defects with severe hypovolemia, for example, in aortic stenosis.

Digestive system

With congenital heart disease, the liver and spleen may enlarge due to venous congestion in heart failure (usually no more than 1.5-2 cm). Venous congestion of the mesenteric vessels and esophagus may be accompanied by vomiting, more often during physical exertion, and abdominal pain (due to stretching of the liver capsule).

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Classification of congenital heart defects

There are several classifications of congenital heart defects.

International Classification of Diseases, 10th revision. Congenital heart defects are classified in sections Q20-Q28. Classification of Heart Diseases in Children (WHO, 1970) with SNOP (Systematic Nomenclature of Pathology) codes used in the USA and with ISC codes of the International Society of Cardiology.

Classification of congenital heart and vascular defects (WHO, 1976), containing the section “Congenital anomalies (malformations)” with the headings “Anomalies of the bulbus cordis and anomalies of the closure of the cardiac septum”, “Other congenital anomalies of the heart”, “Other congenital anomalies of the circulatory system”.

The creation of a unified classification presents certain difficulties due to the large number of types of congenital heart defects, as well as the differences in the principles that can be used as the basis for the classification. The A.N. Bakulev Scientific Center for Cardiovascular Surgery developed a classification in which congenital heart defects are divided into groups taking into account anatomical features and hemodynamic disturbances. The proposed classification is convenient for use in practical activities. In this classification, all congenital heart defects are divided into three groups:

1. Pale type congenital heart disease with arteriovenous shunt, i.e. with blood flow from left to right (VSD, ASD, patent ductus arteriosus);
2. Blue type congenital heart disease with venoarterial shunt, i.e. with blood shunt from right to left (complete transposition of the great vessels, tetralogy of Fallot);
3. Congenital heart disease without discharge, but with an obstruction to ejection from the ventricles (pulmonary artery stenosis, coarctation of the aorta).

There are also congenital heart defects that do not fall into any of the three groups listed above in terms of their hemodynamic characteristics. These are heart defects without blood shunting and without stenosis. These include, in particular: congenital mitral and tricuspid valve insufficiency, Ebstein's tricuspid valve developmental anomaly, and corrected transposition of the great vessels. Common coronary vessel developmental defects also include abnormal origin of the left coronary artery from the pulmonary artery.

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Diagnosis of congenital heart defects

In the diagnosis of congenital heart defects, all examination methods are important: anamnesis collection, objective data, functional and radiological methods.

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Electrocardiography

ECG is important already at the initial stages of diagnostics of congenital heart defects. It is important to evaluate all parameters of a standard electrocardiogram.

Changes in the pacemaker characteristics are not typical for congenital heart defects. Heart rate almost always increases in congenital heart defects due to hypoxia and hypoxemia. Heart rhythm regularity rarely changes. In particular, heart rhythm disturbances are possible with ASD (characterized by extrasystole), with anomalies in the development of the Ebstein tricuspid valve (attacks of paroxysmal tachycardia).

Deviation of the electrical axis of the heart has a certain diagnostic value. For overload of the right ventricle, pathological deviation of the electrical axis of the heart to the right is characteristic (VSD, ASD, tetralogy of Fallot, etc.). Pathological deviation of the electrical axis of the heart to the left is typical for open arterial flow, an incomplete form of atrioventricular communication. Such changes on the ECG may be the first signs that raise suspicion of congenital heart defects.

Changes in intraventricular conduction are possible. Some variants of intraventricular blockades occur with certain heart defects. Thus, for ASD, the presence of an incomplete blockade of the right bundle branch of His is quite typical, and for Ebstein's tricuspid valve anomaly, a complete blockade of the right bundle branch of His is typical.

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X-ray examination

X-ray examination must be performed in three projections: direct and two oblique. Pulmonary blood flow and the condition of the heart chambers are assessed. This method in topical diagnostics of congenital heart defects is important in combination with other examination methods.

Echocardiography

Echocardiography (EchoCG) in most cases is the decisive method in topical diagnostics of such pathology as congenital heart defects. However, the element of subjectivity should be excluded if possible.

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Phonocardiography

Phonocardiography has currently lost its diagnostic significance and can only provide some clarifications to auscultation data.

Angiography

Angiography and catheterization of the heart cavities are performed to determine pressure, blood oxygen saturation, direction of intracardiac discharges, and the type of anatomical and functional disorders.

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