Outdoor arteriosus ( Botallo ) flow

August 12, 2017 17:51 | Genetic Diseases

ductus arteriosus is a vessel that connects the aorta and pulmonary trunk in utero.

Outdoor Botallo duct - a vessel that has retained its function after the expiration of its closure.Outdoor arterial canal often occurs in preterm infants - to 3-37% of the cases, although in the future have often closes spontaneously.

patent ductus arteriosus have within a few months of life, 50% of babies born weighing less than 1700 in 20% remains open for 1-2 years.Virtually closed duct syndrome in newborns with acute respiratory disorders, which greatly increase the weight of the underlying disease, and sometimes makes the resort to an urgent surgical intervention.The duct is long, narrow and winding or short and wide.Its diameter is 10-15 mm.Often found associated malformations of the gastrointestinal tract, urogenital system and others.

In utero principal amount of blood in the fetus from the right ventricle flows through the ductus arteriosus into the aorta.After the birth of the first breath, pulmonary resis

tance decreases, and at the same time raised the pressure in the aorta, which contributes to the emergence of reverse shunt (from the aorta to the pulmonary artery).High blood oxygen saturation after the pulmonary respiration causes a spasm of the duct.The noise on auscultation of the heart disappears within 15-20 hours after birth (functional closure).Final obliteration (imperforate) and the transformation of the duct in the bundle occurs in the period from 2 to 10 weeks of life.Ductus arteriosus is considered an anomaly if on clinical data it operates after 1-2 weeks after birth.Closing the duct begins at the point of discharge from the pulmonary artery, where a lot of the muscle cells.Perhaps unclosed ductus arteriosus due to a deficiency or muscle cell hypoplasia or elastic fibers in its wall.Increased blood oxygen saturation is the main stimulus for the contraction of muscle cells.

In patent ductus arteriosus is reset oxygenated blood from the aorta to the pulmonary artery.Reset blood from the aorta occurs during systole and diastole period, since both of these phases aortic pressure exceeds that in the pulmonary artery.

defect severity is determined by the following points:

1) the size of the duct;

2) its angle of divergence (more favorably if it departs from the aorta at a sharp angle, worse - if obtuse, as it promotes greater blood discharge);

3) resistance in the pulmonary vessels.

With a large duct a significant amount of blood enters the pulmonary artery and then to the left side of the heart, causing them to overload the increased blood volume.In addition, the pressure in the aorta is transmitted directly through the duct into the pulmonary artery, which causes early development of pulmonary hypertension.Disorders of blood flow with patent ductus arteriosus cause expansion of mainly left heart, but with the development of pulmonary hypertension, especially in its sclerotic stage (see. Above), dominated the expansion of the right ventricle.

ductus arteriosus is more common in girls than in boys.Sex ratio is 2: 1 to 3: 1 are described familial cases blemish.When it is combined with cataract and reduction of brain size of the child has congenital rubella syndrome.The course of the disease may vary from asymptomatic to very severe.Emphasis is placed on factors such as rubella, carried over the mother during pregnancy, premature baby, repeated pneumonia.Often, the first year of life develops underweight, which is typical for children with severe heart failure.It is a serious condition typical of premature babies.Children born at gestational age 30 weeks, have pronounced discharge of blood from the aorta to the pulmonary artery.Arterial canal have not reduced and remains high for a long time.

children with patent ductus arteriosus lag behind in development.They complain of fatigue, shortness of breath with a small load.Usually they are inactive.More adults may complain of palpitations, irregular heart.There are often pneumonia.In children with patent ductus arteriosus attention is drawn to the development of cardiac hump.The exception is the small size of the duct.When the feeling of the heart is determined by a rough shake.By the end of the first week of life, there is a characteristic noise when auscultation phonendoscope.For the ductus arteriosus is characterized by a high, rapid pulse.It defines several high systolic ( "upper") and low diastolic ( "lower"), up to 30-40 mm Hg.Art.(Up to zero) pressure.A sign of a large discharge of blood from the aorta into the pulmonary artery through the duct is heart failure, which manifests palpitations and breathing, enlargement of the liver and spleen size.

One of the possible complications of patent ductus arteriosus is a bacterial endocarditis (bacterial damage the inner lining of the heart), which occurs in 2% of cases, often with a small duct.Another complication may be the development of an aneurysm (bulging of the walls sacciform) flow and its rupture.In some cases, this is combined with bacterial endocarditis.

ductus arteriosus The diagnosis is established on the basis of the survey:

1) expanded the boundaries of the heart auscultation auscultated characteristic of this disease rough systolic-diastolic murmur, so-called "machine" noise;

2) on the electrocardiogram are no changes, forcing the suspected patent ductus arteriosus;

3) presence of a characteristic detected by echocardiography blood flow in a typical place between the aorta and the pulmonary artery in the direction from the aorta to the pulmonary artery;

4) X-rays of lungs are judged on degree of lung tissue changes.

additional child survey methods are: PCG (graphic registration heart murmurs), radiographs of the chest, ultrasound of the heart.In doubtful cases, a cardiac catheterization.

In severe cases of patent ductus arteriosus cardiac glycosides are used (digoxin) and diuretics.Premature babies uncovered flow helps oxygen deficiency, which may be with anemia.This condition requires urgent treatment.The total amount of liquid introduced for these children, should not exceed 70-100 ml per 1 kg of body weight per day.In order to maintain hemoglobin at a normal level, blood transfusions.Oxygen also helps to maintain optimal closing duct for the oxygen level in the blood of the newborn.

75% of premature duct closes spontaneously within the first 4-5 months of life and later.The possibility of such an outcome in term after the 3rd month of life is less than 10%.Life expectancy with patent ductus arteriosus is 39 ± 4 years, and only a small number of people live to 50-60 years.Consequently, patent ductus arteriosus, even small size leads to premature death.

Indications for surgical treatment of defect at an early age are circulatory failure that does not respond to treatment with medicines, underweight, the progression of pulmonary hypertension (increased pressure in the pulmonary artery).Premature infants with patent ductus arteriosus, and respiratory disorders urgent surgery is performed under stable treatment of heart failure.

Particularly noteworthy are the children whose ductus arteriosus is accompanied by pulmonary hypertension.The uncertainty of the method of treatment in such cases is associated with a high mortality rate during surgery and in the postoperative period.The mortality rate in these children is 25%.Bacterial endocarditis is performed surgical correction, because without complete cure of endocarditis impossible.Before the operation, carried out medical treatment.

operation is ligation of patent ductus arteriosus.Long-term results of surgical correction of the defect good mortality after surgery is minimal.