- anatomical structure
- How does aortic valve
- Congenital alterations of the aortic valve
- Acquired defects
- Pathological changes in lesions of the aortic valve
- place butterfly valve including the aortic defects
- As shown valvular insufficiency
- role in the formation of the valves aortic stenosis
- survey treatment without surgery
heart valve system provides directional emission of blood from one chamber to the other, in the main vessels.From the simultaneous opening and closing of the valves depends on the correct distribution of the flow, the force of myocardial contraction.After the aorta enriched with oxygen and nutrients in the blood to the general circulation.
is malfunctioning aortic valve leads to heart failure, accompanied by organ dysfunction.
congenital bicuspid aortic valve (synonym - bicuspid aortic valve) on the clinical manifestations - rather offensive state, is dangerous complications.
valve is located on the border of the aorta and the left ventricle.Its main function - the blood flow return warning ventricle during systole which has already passed into the aorta.
valve structure consists of:
- fibrous ring - strong connective tissue formation, clearly separating left ventricle and the initial part of the aorta;
- three semilunar cusps - represent a continuation of the endocardial layer of the heart, composed of connective tissue and muscle fiber bundles, the distribution of collagen and elastin allows tight interlock, overlap the lumen of the aorta and to redistribute the load on the vessel wall;
- sinuses - are behind the aortic sinus, right behind the doors crescent, of which track starts left and right coronary arteries.
between a part of the valve connected spikes (commissures)
structure Violation leads to a picture of a congenital defect (CHD) or acquired nature.Congenital heart disease detected in a child in the neonatal period on the symptoms and auscultation picture.
How does aortic valve
tricuspid aortic valve structure of the bivalve mitral distinguishes the absence of the papillary muscles and chordae tendon.Therefore, it is opened and closed only under the influence of the pressure difference in the cavity of the left ventricle and the aorta.
During the opening - elastin fibers of the ventricular folds pressed against the walls of the aorta, an opening for blood flow is released.At the same time the root of the aorta (the initial part) is compressed and pulls them over.If the pressure in the ventricle exceeds the pressure in the aorta, blood flows into the receptacle.
closing flap swirl flows in the sinuses.They are debarred from the aortic valve to the center of the wall.Flexible flaps are closed tightly.The sound is heard closing stethoscope.
Congenital aortic valve changes
exact causes of congenital disorders hitherto unknown.Most often it occurs in conjunction with other UPU - the mitral valve.
most frequent developmental defects:
- formation of two leaflets instead of three (two-folding the aortic valve);
- one of the valves in the sizes more than others, stretches and sags;
- one fold less than the others, is underdeveloped;
- holes in leaves.
insufficiency aortic valve frequency is second only to defects of the mitral valve.Usually it combined with stenosis of the aortic lumen.Most often found in boys.
Causes of acquired defects are serious chronic diseases, so they are more likely to form in adulthood.Established communication with the greatest:
- septic conditions (endocarditis);
- transferred pneumonia;
nature of pathological changes is different:
- When rheumatic - leaf soldered at the base and shrivel.
- Endocarditis deforms valves, starting from the free edge.There warty growths formed by proliferation of colonies of streptococci, staphylococci, chlamydia.They delayed fibrin and leaf fused together, losing the ability to fully closed.
- Atherosclerosis defeat proceeds from the wall of the aorta, valves thicken, developing fibrosis, calcium salts are deposited.
- Syphilitic changes also apply to valves of the aorta, but accompanied by a loss of elastic fibers, the expansion of the fibrous ring.The valves become dense, immobile.
Causes inflammation may be an autoimmune disease (systemic lupus erythematosus), chest trauma.
Older people have atherosclerosis of the aortic arch leads to the expansion of the root, stretching and valve sclerosis.
Pathological changes in the defeat
result of congenital and acquired changes is the formation of insufficient closing of valves, this is reflected in the return of the blood in the cavity of the left ventricle during its relaxation.The cavity expands and elongates in size.
Forced amplification rate is eventually failure of compensatory mechanisms and hypertrophy of the left ventricle muscle layer.It is followed by an extension of the left venous holes connecting the atrium to the ventricle.Overloading with left heart through the pulmonary vessels transferred to the right heart.
Impaired valve leaflets to the tight closure leads to the formation of disease, prolapse under the influence of the reverse flow of blood.Usually both forms of aortic stenosis holes.The clinical picture can talk about the predominance of one type of blemish.Both increase the load on the left ventricle.Features flow necessarily considered when choosing a method of treatment.
place bicuspid aortic valve malformations among
detection rate of bi-leaflet aortic valve among children up to 20 cases for every thousand births.In adulthood, it is 2%.Most people have two wings is enough to ensure normal blood flow throughout a person's life and does not require treatment.
On the other hand - when examining children with CHD in the form of aortic stenosis and 85% identify variant bicuspid aortic valve.In adults, similar changes are found in half of the cases.
«Throughput" aortic orifice area is dependent on seam options valves.
Usually one of two valves larger than the other, the opening has an asymmetric form of the type "fish's mouth»
If congenital pathology "accumulate" heart defect causes an infectious nature, atherosclerosis of the aorta, the valves faster than usual fail undergo fibrosis, calcification.
As shown valvular insufficiency
Symptoms of incomplete closure of the aortic valve are beginning to appear, if the reverse flow threw the blood reaches 15-30% of the ventricular cavity.Prior to this, people feel good, even sports.Patients complain of:
- headaches with vertigo;
- moderate shortness of breath;
- feeling vascular pulsation in the body;
- anginal pain in the heart;
- tendency to fainting.
cardiac decompensation mechanisms of adaptation appears:
- shortness of breath;
- swelling of the extremities;
- heaviness in the right upper quadrant (due to the stagnation of blood in the liver).
On examination, the doctor notes:
- pale skin (peripheral reflex spasm of small capillaries);
- expressed pulsation of the cervical arteries, language;
- change in pupil diameter in accordance with the pulse;
- bulging chest of a nasty blow to the heart neokostenevshuyu sternum and ribs in children and adolescents.
Reinforced beats doctor felt on palpation of the heart region.Auscultation revealed a typical systolic murmur.
blood pressure measurement shows the growth of the upper digits and lower reduction, for example, 160/50 mm Hg.Art.
role in the formation of the valves aortic stenosis
Repeated attacks of rheumatic aortic valves shrivel and free edges are welded so that the narrow outlet.Fibrous ring sclerosing, further enhancing the stenosis.
Symptoms depend on the degree of narrowing of the openings.It is considered critical stenosis diameter 10 mm2 or less.Depending on the area free of the aortic orifice to distinguish between forms:
- light - more than 1.5 cm2;
- modest - from 1 to 1.5 cm 2;
- heavy - less than 1 cm2.
- pain by type of angina attacks caused by insufficient blood flow to the coronary arteries;
- dizziness and fainting due to cerebral hypoxia.
signs of heart failure occur in the case of decompensation.
physician during the examination notes:
- pale skin;
- palpation determined offset to the left and down the apical impulse, "shake" at the base of the heart at the expiration of the type "cat's purr";
- tendency to bradycardia;
- typical sounds on auscultation.
On radiographs (including with x-rays) is easily visible enlargement of the aortic arch, an enlarged left and right ventricles.
ECG - shows the displacement of the left electric axis, signs of myocardial hypertrophy, may beats.
Fonokardiograficheskie signs - can objectively investigate a heart murmur.
ultrasound or echocardiography - indicates an increase in the left ventricle, the most accurately describes the pathology of valves (structural change, shaking the flaps, the width of the remaining holes).
Doppler - the most informative
Doppler method allows:
- see the return flow of blood;
- diagnose the degree of valve prolapse (internal deflection);
- establish compensatory possibilities of the heart;
- determine the indications for surgical treatment;
- assess the severity of the stenosis on the violation of the norms of the pressure gradient (from 3 to 8 mm Hg. Art.).
The functional diagnosis of aortic stenosis using Doppler taken into account the following gradient deviation (difference between the pressure in the aorta and the left ventricle):
- easy stenosis - less than 20 mm Hg.Article .;
- moderate - from 20 to 40;
- heavy - more than 40, usually 50 mm Hg.Art.
development of heart failure is accompanied by a decrease in the gradient to 20.
Variety echocardiography - transesophageal option is carried out by administering to the esophageal probe closer to the heart of a special sensor.It allows you to measure the area of the aortic rings.
by catheterization of the heart chambers and vessels measure the pressure in the cavity (on a gradient) and study features of the passage of the blood flow.This method is used in specialized centers for the diagnosis in people older than 50 years, if you can not otherwise resolve the question of the method of surgery.
Congenital propose to operate after 30 years before - only with fast decompensation
Treatment Without Surgery Treatment
hole narrowing of the aortic valve insufficiency and required only if you suspect the beginning of decompensation, detection of arrhythmia, severe damage.Proper use of drugs eliminates the need for surgery.
applied group of pharmacological agents that increase myocardial contractility, and arrhythmias can prevent the manifestation of failure.These include:
- calcium antagonists;
- drugs, dilates coronary vessels.
surgery to replace the aortic valve prosthesis is required for those patients whose left ventricle is already unable to cope with pumping blood.Currently, it attaches great importance to the development and implementation of techniques for aortic valve.Caring about the safety of their own valve is extremely important for the child.Babies any undesirable species prostheses because they are not able to grow and require destination anticoagulants.
acquired defect types operate in the 55 and older while conducting treatment of the underlying disease.
Indications for surgery are determined by major functional impairment identified in the survey.
Such an approach is not possible in severe deformation of the valve, the aortic tissues modified
Types of surgery:
- balloon counterpulsation - refers to a method that allows to do without opening the chest.To the valve through the femoral artery, the balloon is fed sleeping, then it is inflated with helium, which spreads wrinkled folds and closes the hole better.Method is often used in the treatment of children, little traumatic.
- The aortic valve include a mandatory patient replacement of the aortic valve with an artificial one made of metal or silicone.The operation is well tolerated by patients.After replacing the significantly improved health outcomes.Bioprosthesis of the pulmonary artery by a deceased person or animal is used infrequently, mainly in patients after 60 years.A serious drawback - the need for opening the chest and the use of cardiopulmonary bypass.
- For double wing valve is designed for plastic surgery with maximum preservation of tissue valves.
endovascular prosthesis (endovasal) - the future of cardiac surgery.It held in centers with high-tech help.Virtually no contraindications.Under local anesthesia, the aorta special probe is supplied folded valve.The probe disclosed and sets the valve on the stent type.It does not require extracorporeal circulation.
patients with pathology of the aortic valve should always be observed by the cardiologist and once a year to consult a heart surgeon.Choose the correct dosage of medication, and to offer the right method of treatment can only be a specialist doctor.