Aorta aneurism – the pathological local expansion of the site of the main artery caused by weakness of its walls. Depending on localization of an aneurysm of an aorta it can be shown by thorax or stomach pain, existence of the pulsing opukholevidny education, symptoms of a compression of the next bodies: short wind, cough, dysphonia, dysphagy, puffiness and cyanosis of the person and neck. The basis of diagnosis of aneurism of an aorta is made radiological (a X-ray analysis of a thorax and abdominal cavity, an aortografiya) also by ultrasonic methods (UZDG, UZDS of a chest/belly aorta). Surgical treatment of aneurism assumes performance of its resection with prosthetics of an aorta or the closed endolyuminalny prosthetics of aneurism by a special endoprosthesis.
Aneurism of an aorta is characterized by irreversible expansion of a gleam of an arterial trunk on the limited site. Ratio of aneurisms of an aorta of various localization approximately following: aneurisms of a belly part of an aorta make 37% of cases, the ascending department of an aorta – 23%, aorta arches – 19%, the descending department of a chest aorta – 19,5%. Thus, nearly 2/3 all pathologies fall to the share of aneurisms of a chest aorta in cardiology. Aneurisms of chest department of an aorta are often combined with other aortal defects - aortal insufficiency and a koarktatsiy aorta.
Classification of aneurisms of an aorta
In vascular surgery several classifications of aneurisms of an aorta taking into account their localization on segments, forms, structures of walls are offered, to an etiology. According to segmentary classification allocate: to an aneurysm of a sine of Valsalva, an aneurysm of the ascending department of an aorta, an aorta arch aneurysm, an aneurysm of the descending department of an aorta, an aneurysm of a belly aorta, an aneurysm of the combined localization - a torakoabdominalny part of an aorta.
Assessment of a morphological structure of aneurisms of an aorta allows to subdivide them into true and false (pseudo-aneurisms). True aneurism is characterized by thinning and protrusion outside of all layers of an aorta. On an etiology true aneurisms of an aorta usually atherosclerotic or syphilitic. The wall of false aneurism is presented by the connecting fabric formed owing to the organization of the pulsing hematoma; own walls of an aorta are not involved in formation of false aneurism. Pseudo-aneurisms by origin more often happen traumatic and postoperative.
In a form meshotchaty and spindle-shaped aneurisms of an aorta meet: the first are characterized by local protrusion of a wall, the second – diffusion expansion of all diameter of an aorta. Normal at adults diameter of the ascending aorta makes about 3 cm, the descending chest aorta - 2,5 cm, a belly aorta - 2 cm. Speak about aneurism of an aorta at increase in diameter of a vessel on the limited site in 2 and more times.
Taking into account a clinical current distinguish the uncomplicated, complicated, stratified aorta aneurisms. The ruptures of an anevrizmatichesky bag which are followed by massive internal bleeding and formation of hematomas are among specific complications of aneurisms of an aorta; thromboses of aneurism and thrombembolia of arteries; phlegmons of surrounding fabrics owing to infection of aneurism. The special type is represented by the stratified aorta aneurism when through a rupture of an internal cover blood gets between layers of a wall of an artery and extends under pressure on the vessel course, gradually stratifying it.
Etiologichesky classification of aneurisms of an aorta is in detail stated by consideration of causes of illness.
Aorta aneurism reasons
On an etiology all aneurisms of an aorta can be divided on congenital and acquired. Formation of congenital aneurisms is connected with hereditary diseases of a wall of an aorta – Marfan's syndrome, a fibrous dysplasia, Elersa-Danlos's syndrome, Erdkhaym's syndrome, hereditary deficiency of elastin, etc.
The acquired aneurisms of an aorta of an inflammatory etiology arise owing to a specific and nonspecific aortit at fungal damages of an aorta, syphilis, postoperative infections. The cases caused by atherosclerosis, defects of sutural material and artificial limbs belong to number of not inflammatory or degenerate aneurisms of an aorta. Mechanical injuries of an aorta lead to formation of gemodinamicheski-poststenotichesky and traumatic aneurisms. Idiopathic aneurisms develop at an aorta medionekroza.
Advanced age, male, arterial hypertension, tobacco smoking and abuse of alcohol, hereditary otyagoshchennost are considered as risk factors of formation of aneurisms of an aorta.
Pathogenesis of aneurisms of an aorta
Except deficiency of a wall of an aorta mechanical and haemo dynamic factors take part in formation of aneurism. Aorta aneurisms arise in functionally intense zones experiencing the raised strain owing to the high speed of a blood-groove, the steepness of a pulse wave and its form more often. The chronic travmatization of an aorta, and also hyperactivity of proteolytic enzymes cause destruction of an elastichesky framework and nonspecific degenerate izmeyoneniye in a vessel wall.
The created aorta aneurism progressiruyushche increases in sizes as tension on its walls increases in proportion to expansion of diameter. The blood-groove in an anevrizmatichesky bag is slowed down and gains turbulent character. Only about 45% of blood of the volume which is in aneurism come to the disteel arterial course. It is connected with the fact that, getting into an anevrizmatichesky cavity, blood directs along walls, and the central stream restrains the mechanism of turbulence and presence at aneurism of trombotichesky masses. Existence of blood clots in a cavity of aneurism is risk factor of tromboemboliya of disteel branchings of an aorta.
Aorta aneurism symptoms
Clinical displays of aneurisms of an aorta are variable and caused by localization, the sizes of an anevrizmatichesky bag, its extent, a disease etiology. Aneurisms of an aorta can proceed asymptomatically or be followed by poor symptomatology and come to light on routine inspections. As the leading display of aneurism of an aorta serves the pain caused by defeat of a wall of an aorta, its stretching or a compression syndrome.
The clinic of aneurism of a belly aorta is shown by the passing or constant poured pains, discomfort in a stomach, an eructation, weight in an epigastriya, feeling of overflow of a stomach, nausea, vomiting, intestines dysfunction, weight loss. The symptomatology can be connected with a compression of kardialny department of a stomach, a 12-perstny gut, involvement of visceral arteries. Often patients independently define existence of the strengthened pulsation in a stomach. At a palpation the intense, dense, painful pulsing education is defined.
Pains in heart or behind a breast, caused by a sdavleniye or a stenozirovaniye of coronal arteries are typical for aneurism of the ascending department of an aorta. Patients with aortal insufficiency are disturbed by short wind, tachycardia, dizziness. Aneurisms of the big sizes cause development of a syndrome of the top hollow vein with headaches, puffiness of the person and the top half of a trunk.
Aneurism of an arch of an aorta leads to a gullet compression with the dysphagy phenomena; in a case the perezhatiya of a returnable nerve arises an osiplost of a voice (dysphonia), dry cough; interest of the wandering nerve is followed by bradycardia and a salivation. At a compression of a trachea and bronchial tubes short wind and stridorozny breath develop; at a lung root sdavleniye - developments of stagnation and frequent pneumonia.
At irritation the left hand and shovel pains arise aneurism of the descending aorta of a periaortalny sympathetic texture. In case of involvement of intercostal arteries ischemia of a spinal cord, paraparesis and a paraplegia can develop. The compression of vertebras is followed by their uzuration, a degeneration and shift with formation of a kifoz; the sdavleniye of vessels and nerves is clinically shown by radikulyarny and intercostal neuralgia.
Aorta aneurism complications
Aneurisms of an aorta can be complicated by a gap with development of massive bleeding, collapse, shock and acute heart failure. The break of aneurism can happen in system of the top hollow vein, a pericardiac and pleural cavity, a gullet, an abdominal cavity. At the same time fatal states – a syndrome of the top hollow vein, a haemo pericardium, a tamponad of heart, , pulmonary, gastrointestinal or intra belly bleeding develop heavy, sometimes.
At a separation of trombotichesky masses from an anevrizmatichesky cavity the picture of sharp occlusion of vessels of extremities develops: cyanosis and morbidity of fingers of feet, on skin of konechyonost, the alternating lameness. At thrombosis of renal arteries there is renovaskulyarny arterial hypertension and a renal failure; at damage of brain arteries – a stroke.
Diagnosis of aneurism of an aorta
Diagnostic search at aneurism of an aorta includes assessment of subjective and objective data, carrying out radiological, ultrasonic and tomographic researches. Presence of systolic noise at a projection of expansion of an aorta is the Auskultativny sign of aneurism. Aneurisms of a belly aorta are found at a stomach palpation in the form of the opukholevidny pulsing education.
The plan of radiological inspection of patients with aneurism of a chest or belly aorta joins roentgenoscopy and a X-ray analysis of a thorax, a survey X-ray analysis of an abdominal cavity, a X-ray analysis of a gullet and stomach. At recognition of aneurisms of the ascending department of an aorta the echocardiography is used; in other cases UZDG (UZDS) of a chest/belly aorta is carried out.
The computer tomography (MSKT) of a chest/belly aorta allows to present precisely and visually anevrizmatichesky expansion, to reveal existence of stratification and trombotichesky masses, a paraaortal hematoma, the centers of a kaltsinoz. At the final stage of inspection carry out an aortografiya according to which are specified localization, the sizes, extent of aneurism of an aorta and its attitude towards the next anatomical structures. By results of comprehensive tool examination the decision on indications to expeditious treatment of aneurism of an aorta is made.
The aneurysm of a chest aorta should differentiate from tumors of lungs and a sredosteniye; to an aneurysm of a belly aorta – from volume formations of an abdominal cavity, damage of lymph nodes of a bryzheyka, zabryushinny tumors.
Treatment of aneurism of an aorta
At the asymptomatic not progressing course of aneurism of an aorta are limited to dynamic observation of the vascular surgeon and radiological control. For decrease in risk of possible complications hypotensive and antikoagulyantny therapy, decrease in level of cholesterol is carried out.
Surgery is shown at aneurisms of a belly aorta with a diameter more than 4 cm; aneurisms of a chest aorta with a diameter of 5,5-6,0 cm or at increase in aneurisms of the smaller size more than on 0,5 cm for half a year. At a rupture of aneurism of an aorta of the indication to the emergency surgical intervention absolute.
Surgical treatment of aneurism of an aorta consists in excision of an anevrizmaticheska of the changed site of a vessel, an ushivaniya of defect or its replacement with a vascular artificial limb. Taking into account anatomic localization the resection of aneurism of a belly aorta, chest aorta, an arch of an aorta, a torakoabdominalny part of an aorta, subkidney department of an aorta is carried out.
At gemodinamichesk of significant aortal insufficiency the resection of the ascending chest aorta is combined with prosthetics of the aortal valve. As an alternative to open vascular intervention serves endovascular prosthetics of aneurism of an aorta with installation of a stent.
Forecast and prevention of aneurism of an aorta
The forecast of aneurism of an aorta, mainly, is defined by its sizes and the accompanying atherosclerotic defeat of cardiovascular system. In general the natural course of aneurism adverse is also connected with high risk of death from a rupture of an aorta or tromboembolichesky complications. The probability of a rupture of aneurism of an aorta with a diameter of 6 and more than a cm makes 50% a year, smaller diameter – 20% a year. Early identification and planned surgical treatment of aneurisms of an aorta is justified low intraopeyoratsionny (5%) by a lethality and the good remote results.
Preventive recommendations include control HELL, the organization of the correct way of life, regular observation at the cardiologist and an angiokhirurg, medicamentous therapy of the accompanying pathology. Persons from risk groups on development of aneurism of an aorta should undergo screening ultrasonic inspection.