Tetralogy of Fallot
Tetralogy of Fallot - a severe congenital heart disease, which is characterized by hypoplasia of the right ventricular outflow tracts offset partitions to one side.As a result of these changes produced four major defect: hypertrophic myocardial changes, destroktopozitsiya aorta, subaortic defects stenosis of the interventricular septum and the output of the legal department of the ventricle.
Clinically, this pathology as tetralogy of Fallot manifested delayed physical and mental development, early cyanosis of the skin (sometimes cyanosis evident from the first months after birth, but more often a year or even later), shortness of breath or severe odyshechno-cyanotic episodes, frequentfainting, nausea, dizziness and constant weakness.
Tetralogy of Fallot causes
reason of tetralogy of Fallot may be a violation of the full development of the heart for 2-8 weeks of embryonic development of the fetus.In addition, a pregnant woman borne infectious diseases such as measles,
noted the development of tetralogy of Fallot in children with dwarfism syndrome Amsterdam (Cornelia de Lange), which includes such pathological conditions as a "clown face";Gothic sky;deformity of the spine and chest;choanal atresia;strabismus;atrophy of the optic nerve;deformation of the ears;hypertrichosis;myopia;the absence of some fingers;severe malformations of the internal organs;low birth weight;small feet and hands.
Because aorta extends from both the left and from the right ventricle, in severe stenosis or major defects during systole nearly all the blood from the ventricles and the aorta comes in very small amounts in the pulmonary artery.As a result, developing right ventricular failure.If you have moderate stenosis manifested atsianoticheskaya form of tetralogy of Fallot.With increasing cross-stenosis occurs shunt, and then from right to left with a transition to step atsianoticheskoy pronounced form.
Tetralogy of Fallot form
Today distinguish four basic forms of obstruction of the right ventricle ductless: embryological, hypertrophic, tubular, multi-component.
embryology form.This form of the disease characterized by a shift conical baffle in front and to the left.The zone of maximum stenosis according to the muscle ring.This fibrinous ring is not deformed.
Hypertrophic form.Obstruction in this case is characterized by the same offset partitions, as in the embryological form but, in addition, marked by its expression hypertrophic changes in the proximal segment.In this case, the maximum area of stenosis at the level of the output of the right ventricle and the Department of dividing the muscle layer.
Tubular shape.Obstruction in the third type of tetralogy of Fallot is caused by uneven division formed a common arterial trunk.As a result, pulmonary becomes truncated cone, tapered and hypoplastic.It is also accompanied by a form of fibrinous ring hypoplasia and pulmonary artery stenosis.
multipart forms.The cause of obstruction in this form of tetralogy of Fallot is the lengthening of the cone walls.
The degree of hemodynamic disturbances manifested as ductless obstruction of the right ventricle.In marked stenosis observed blood flow of both ventricles mainly in the aorta and in a very small volume in the pulmonary artery, and this state is accompanied by arterial hypoxia.
with moderate stenosis in peripheral resistance greater outflow tract, and therefore develops a left-right ventricular ejection of blood, which subsequently leads to atsianoticheskoy form of the disease.In another way, this condition is called - the pale form of tetralogy of Fallot.However, over time, "pale" form develops in the "blue" is linked to the development of cross and venoarterialnogo shunt.
Tetralogy of Fallot Symptoms
Depending on the time of the initial symptoms are five main periods of manifestation of tetralogy of Fallot are: early cyanotic stage (the appearance of cyanosis in the first months of life, or close to one year of life), classic stage (the appearance of cyanosis inthe start time of the child's movements), severe stage (attacks of breathlessness with obvious symptoms of cyanosis), late cyanotic stage (early symptoms are not earlier than in 6-10 years) and acyanotic (pale) stage of the disease.
Most often in such diseases as tetralogy of Fallot, meet the following complaints and symptoms: developmental delay;shortness of breath;severe attacks of breathlessness manifestations of cyanosis;central cyanosis;loss of consciousness;convulsions.
objectively during the survey noted:
- pale skin, or cyanotic manifestations;
- a symptom of "clubbing" or "time windows";
- gain of the first heart sound;
- the patient's position on his haunches after small loads;
- the weakening of the second tone of the pulmonary artery;
- presence of systolic murmur or systolic.
diagnosis of Tetralogy of Fallot
To confirm the diagnosis, "tetralogy of Fallot" should provide a complete medical history, clinical symptoms manifest themselves, to spend an electrocardiogram and chest radiograph.
Instrumental methods of diagnosis
ECG (electrocardiogram) during this study shows signs of overload or hypertrophy of certain parts of the heart, atrioventricular block and sick sinus syndrome.
chest radiograph: for tetralogy of Fallot is characterized by the depletion of a pulmonary drawing, bulging arc right or left ventricle, with a pronounced combination of open arterial defect.In young children at the heart of the X-ray looks like "shoe."
echocardiography: This method of diagnosis of tetralogy of Fallot allows us to estimate the size of the cavity of the right ventricle, the degree of narrowing of the output flow, determine the shape of the pathological process (embryology, hypertrophic, multicomponent or tubular).The same method was performed for diagnosis of aortic valve stenosis for the presence, as time undetected problems associated with the development of a valve defect after treatment can lead to rapid decompensation or pulmonary edema.As well as using this method determines the diameter of the fibrous rings and examine the general condition of the valves.
Heart Catheterization: puncture of the heart cavities is carried out in cases where it is necessary to determine the oxygenation of blood in the aorta, measure the pressure in the right ventricle or the pressure gradient between the right ventricle and the pulmonary artery.
Coronary angiography: This method is used to determine the anatomic type of heart disease, the diagnosis of related developmental abnormalities and determine the localization of the coronary arteries and major vessels.
Tetralogy of Fallot treated
Today, there are two basic techniques aimed at the treatment of tetralogy of Fallot: Urgent surgery and therapy (treatment-odyshechno cyanotic attack).
Infants with severe symptoms of cyanosis due to the closure of the ductus arteriosus instantly injected prostaglandin E1 infusion at 0.05 - 0.10 mg intravenously.This manipulation is performed in order to open the ductus arteriosus in the shortest time.
During severe hypoxic episodes give the child a situation in which the legs are pressed to maximize chest, older children just sit down and attack passes, prescribe morphine 0.1 -0.2 mg / kg / m.
Odyshechno-cyanotic attack stoped using oxygen therapy, 1% solution trimeperidine intramuscular injection of 0.05 ml in the first year of life or Nikomedin 0.1 ml.In the absence of the effect of crystalloid administered intravenously.If acidosis is injected 4% sodium bicarbonate, 5% glucose solution with the addition of insulin reopoligljukin and aminophylline.In the absence of the effect of the imposition of emergency is conducted aortolegochnogo anastomosis.It is also possible the use of sedatives and / or vasodilators.
to the specific method of treatment of tetralogy of Fallot include slow intravenous Beto-blockers at 0.1 mg / kg, and then use their tablets at 1 mg / kg per day.
Patients with a disease such as tetralogy of Fallot is strictly contraindicated digoxin, because it increases the ionotropic myocardial function and increases the risk of spasm infudibulyarnogo department of the right ventricle.
contraindication to treatment of tetralogy of Fallot by surgical intervention is irreversible pulmonary hypertension.
The first choice operative method of treatment depends on the anatomical structure of the heart defect.It can be both palliative and radical.Palliative treatment of tetralogy of Fallot involves the imposition of aorto-pulmonary anastomosis, and radical - removal of the stenosis followed by plasticity of the interventricular septum.
Palliative surgery is assigned if odyshechno-cyanotic attacks fails to stop using the medication for a long time, as well as the anatomy of the human body.
most commonly used method of fixing the subclavian-pulmonary anastomosis.The operation is that the subclavian artery is connected to the pulmonary artery using special synthetic implants.Experts recommend to immediately carry out radical treatment.
Radical surgery is generally carried out between the ages of 6 months to 3 years, since they are older the chances of a full recovery decrease.This treatment method provides for plastics interventricular septum and eliminate obstruction of the right ventricle outflow tracts.Full correction of the defect consists of a patch and expansion of the flow.
All patients diagnosed with tetralogy of Fallot, regardless of whether the correction should take place before a visit to the dentist preventive measures, in order to avoid the development of bacteremia.
Tetralogy of Fallot forecast
specific postoperative complications: hypothyroidism;thrombosis of the anastomosis;ventricular arrhythmias;AV block;aneurysm of the right ventricle;infective endocarditis;pulmonary hypertension.Odyshechno-cyanotic attacks are often on their own after 3-4 years.
Postoperative mortality now stands at less than 4% in uncomplicated form of the disease.If you do not operate this pathology, up to 5 years of living out a little more than 55% and up to 10 years - 25-30%, in very rare cases, patients diagnosed with tetralogy of Fallot live up to 75 years.