Defects of Development of Cardiovascular System

Acardia — the absence of the heart is observed only at asymmetric Siamese twins.

Ectopia of the heart is its location out of the thorax. The defect is rare, usually combined with other heart defects. Cervical and extrasternal forms of defect lead to lethal outcome; at abdominal form the viability can be saved.

Dextrocardia — displacement of the heart to the right. It can be observed at an opposite location of all organs, less often as an isolated defect.

Right-side arch of aorta — the most frequent anomaly of all defects of arch. In 20-25 % of cases it is combined with Fallot’s tetrad. In isolated form it does not cause the disturbance of hemodynamics, but can manifest in dysphagia and/or respiratory impairment at squeezing of gullet or trachea.

Double arch of aorta — one arch is disposed in front of trachea, the other — behind the gullet.

Coarctation of aorta — narrowing of the isthmus, less often of pectoral and abdominal aorta. The first signs of decompensation usually manifest by 10 years of child’s life.

Aortic stenosis — pathologic narrowing of the aortic valve orifice. A semilunar valve is thus presented by a diaphragm with an orifice of various size.

Stenosis of pulmonary artery is more often valvular, rarely infundibular, usually is a component of complex heart defects.

An opened arterial defect — persisting of Botallo duct.

Aorticopulmonary fistula (aorticopulmonary defect) — fusion between aorta and the trunk of pulmonary artery as an orifice 10-30 mm by diameter, which is located above semilunar valves, and accompanied by the expressed disturbances of hemodynamics.

The atrial septal defect is one of the most frequent defects of cardiovascular system (7-25 % of all congenital defects of the heart). Primary and secondary atrial septal defects are distinguished, as well as their complete absence (cor trilocular biventriculare with one common auricle).

Lutembacher’s defect (syndrome) — a combination of congenital atrial septal defect with mitral stenosis. Usually there is hypoplasia of the left ventricle and aorta, the right half of the heart is hypertophied, pulmonary artery is extended. Decompensation may occur at any age.

Ventricular septal defect — in most cases it is a part of complex defects: Fallot’s tetrad, Eisenmenger complex, transposition of large vessels, etc.

Cor triolocular biatriatum with one common ventricle — a complete absence of interventricular septum. Cor biloculare (two-chambered heart) — absence of interatrial and interventricular septa.

Fallot’s triad — valval stenosis of pulmonary artery combined with defect of interatrial septum and hypertrophy of the right ventricle.

Fallot’s tetrad — stenosis of pulmonary artery, a high defect of interventricular septum, dextroposition of aortic ostium, "sitting" above the defect, hypetrophy of the right ventricle.

Fallot’s pentalogy — a combination of Fallot’s tetrad with defect of interventricular seprum.

Eisenmenger complex — a high defect of the membranous part of interventricular septum, aorta, which is"sitting" above the defect, and hypertrophy of the right venticle. The pulmonary artery is located and developed normally.

Common aortic trunk — safety of primary embryonic arterial trunk, as a result from the heart one vessel goes out.

Transposition of vessels — origin of aorta from the right ventricle, and pulmonary artery — from the left one. In the absence of roundabout shunts, the defect is incompatible with life.

Аtresia of tricuspid valve, Epstein’s defect, primary pulmonary hypertension, valval anomalies, other heart defects, which incidence in common population makes up 2-5 %.

Defects of Respiratory System. Diaphragm of larynx — the formation of connective tissue covered by mucous membrane, disposed at the level of vocal ligament; it can be complete (atresia of larynx) and partial (stenosis).

Congenital stenosis of trachea and bronchial tubes is, as a rule, the secondary defects caused by squeezing from outside of incorrectly located large vessels (aorta, pulmonary artery).

Agenesia (aplasia) of lung — absence of lung and primary bronchus. Bilateral (at аcephalia) and unilateral аgenesia is encountered.

Hypoplasia of lungs — disorder of bronchial branching and/or insufficient development of respiratory part.

Bronchopulmonary cysts can be multiple and solitary. Contents — air, muddy liquid, pus.

An isolated lobe — an isolated from bronchial tree site of pulmonary tissue, supplied with blood from branches of thoracic aorta.

Congenital diaphragmatic hernia — moving of organs of abdominal cavity into the thorax through the defect in diaphragm or through its natural openings.

Defects of Development of Gastrointestinal System. Agenesis of any part of gastrointestinal system.

Hypoplasia — shortening of any part of gastrointestinal system.

Hyperplasia — expansion and lengthening of sites of gastrointestinal system.

Atresia and stenosis — absence or narrowing of lumen of various parts of the intestinal tube — the most frequent reason of impassability in children died in perinatal period. There is atresia of oesophagus, duodenum, atresia and stenosis of jejunum and ileum, аnorectal аtresia and stenosis.

Duplication, heterotopy of organs of gastrointestinal system, persisting vitelline duct are typical forms of congenital defects.

Congenital defects of pancreas, liver and biliary ducts are encountered as аgenesia, wrong division into lobes, duplication, etc.

Defects of Development of Urinary System

Anomalies of quantity and size — arenia (аgenesia), hypoplasia, duplication of kidney (in combination with doubling of ureter, without doubling of ureter).

Anomalies of structure (anomalies of differentiation) of renal parenchyma — dysplasias (cortico-medullar, or mixed, cortical, medullar), polycystic disease (total, cortical, medullar).

Anomalies of form — horseshoe-, biscuit-, L- and S-shaped.

Anomalies of position (dystopy) of kidney — thoracic, lumbar, iliac, pelvic.

Defects of Development of Genital System. The defects of genital system often combine with defects of pelvic organs (urinary system, rectum) and perineum. In perinatal period many of them are still indistinctly expressed and that’s why are diagnosed incompletely.

The most typical defects of this system are:

Cryptorchidism — localization of testicle in any segment of its descending into scrotum. In perinatal period the diagnosis of cryptorchidism is possible only at its abdominal form.

Ectopia of testicle — testicular position is outside the usual pathway of descent (in femoral canal, behind the scrotum, etc).

False hermophroditism — disparity between the structure of gonads and structure of genitalia. The defect can be male and female. At false male hermophroditism (androgyny) the patients have testicles, and the external genital organs are formed by a female type or are found in one or another degree of feminization. At false female hermophroditism the internal genital organs are structurally normal: the patient has the ovaries, uterus, tubes, and the vagina. On the other hand, the external genital organs are structurally similar to the male ones: the clitoris is enlarged in a form of penis, the labia majora resemble a scrotum, the vagina in its lower third portion may be connected with the urethra (urogenital sinus).

True hermophroditism is the presence of the testicle on one side, and ovary — on the opposite side. It may be ovotestis on the opposite side, i.e. formation having both male and female gonads. The secondary sexual characters are mixed in case of true hermophroditism. The defect is rarely encountered.

Defects of Development of the Musculoskeletal System. In practical neonatology the defects of development of the musculoskeletal system in majority of cases are the concomitant diseases or a component of multiple defects.

System Defects of the Musculoskeletal Apparatus.Achondrogenesis — the incidence is not more than 1 case per 42,000 births. Children with achondrogenesis have characteristic appearance: disproportionate large head, wide sunk down dorsum of nose, significant shortening of the trunk, short, sometimes fractured ribs. Death occurs due to severe hypoplasia of lungs caused by narrowness of thoracic cavity.

Achondroplasia (lethal dwarfism) — a narrow thorax, short extremities at normal length of the trunk, horizontal origin of thighs, skull with high frontal bulge, wide sinking down dorsum of nose.