Aneurism of a belly aorta – a local vybukhaniye or diffusion expansion of a wall of an aorta in its belly department. Aneurism of a belly aorta can proceed asymptomatically or find itself a pulsation, belly-aches of various intensity, at a rupture of aneurism – clinic of intra belly bleeding. Diagnosis of aneurism includes carrying out a survey X-ray analysis of an abdominal cavity, UZDG of a belly aorta, a X-ray contrast angiography, KT. Treatment of aneurism of a belly aorta exclusively surgical: an open resection of an anevrizmatichesky bag with replacement to the excised part with a synthetic artificial limb or endoprosthesis replacement.
Aneurism of a belly aorta
Aneurism of a belly aorta – pathological expansion of a belly part of an aorta in the form of protrusion of its wall on the site from the XII chest to the IV—V lumbar vertebra. In cardiology and angiosurgery about 95% of all anevrizmatichesky changes of vessels fall to the share of aneurisms of a belly aorta. Among men 60 years of an aneurysm of a belly aorta are more senior it is diagnosed in 2-5% of cases. Despite a possible asymptomatic current, aneurism of a belly aorta is inclined to progressing; on average its diameter increases by 10% a year that quite often leads to thinning and a rupture of aneurism with a lethal outcome. In the list of the most frequent causes of death of an aneurysm of a belly aorta takes the 15th place.
Classification of aneurism of a belly aorta
Anatomic classification of aneurisms of a belly aorta according to which allocate the infrarenalny aneurisms located below an otkhozhdeniye of renal arteries (95%) and suprarenalny with localization above renal arteries is of the greatest clinical value.
In a form of protrusion of a wall of a vessel distinguish meshotchaty, the diffusion spindle-shaped and stratified aneurisms of a belly aorta; on a wall structure – true and false aneurisms.
Taking into account etiologichesky factors of aneurism of a belly aorta are subdivided on congenital and acquired. The last can have not inflammatory etiology (atherosclerotic, traumatic) and inflammatory (infectious, syphilitic, infectious and allergic).
By option of a clinical current of an aneurysm of a belly aorta happens uncomplicated and complicated (stratified, become torn, trombirovanny). Diameter of aneurism of a belly aorta allows to speak about small (3-5 cm), average (5-7 cm), big (over 7 cm) and huge aneurism (with a diameter of 8-10 times over diameter of infrarenalny department of an aorta).
On the basis of prevalence A. A. Pokrovyosky and . distinguish 4 types of aneurism of a belly aorta:
- I – infrarenalny aneurism with a disteel and proximal isthmus, sufficient on extent;
- II - infrarenalny aneurism with a proximal isthmus, sufficient on extent; extends before bifurcation of an aorta;
- III - infrarenalny aneurism with involvement of bifurcation of an aorta and podvzdoshny arteries;
- IV – infra-and suprarenalny (total) aneurism of a belly aorta.
Reasons of aneurism of a belly aorta
According to researches, the major etiologichesky factor of aneurisms of an aorta (aneurism of an arch of an aorta, aneurism of a chest aorta, aneurism of a belly aorta) is atherosclerosis. In structure of the reasons of the acquired aorta aneurisms 80-90% of cases fall to its share.
More rare acquired origin of aneurisms of a belly aorta coherently with inflammatory processes: a nonspecific aortoarteriit, specific defeats of vessels at syphilis, tuberculosis, salmonellosis, mycoplasmosis, rheumatism.
The fibrous and muscular dysplasia - congenital inferiority of an aortal wall can be a prerequisite of the subsequent formation of aneurism of a belly aorta.
Rapid development of vascular surgery in the last decades led to increase in number of the yatrogenny aneurisms of a belly aorta connected with technical errors when performing an angiography, reconstructive operations (dilatation/stenting of an aorta, a tromboembolektomiya, prosthetics). The closed injuries of an abdominal cavity or a backbone I can promote developing of traumatic aneurisms of a belly aorta.
About 75% of patients with aneurism of a belly aorta are made by smokers; at the same time the risk of development of aneurism increases in proportion to an experience of smoking and quantity daily the smoked cigarettes. The age is more senior than 60 years, the male and presence of the same problems at family members increase risk of formation of aneurism of a belly aorta by 5-6 times.
The probability of a rupture of aneurism of a belly aorta is higher at the patients having an arterial hypertension and chronic diseases of lungs. Besides, the form and the size of an anevrizmatichesky bag matters. It is proved that asymmetric aneurisms are more subject to a gap, than symmetric, and with a diameter of aneurism more than 9 cm mortality from a rupture of an anevrizmatichesky bag and intra belly bleeding reaches 75%.
Pathogenesis of aneurism of a belly aorta
In development of aneurism of a belly aorta inflammatory and degenerate atherosclerotic processes in an aorta wall play a role.
Inflammatory reaction in a wall of an aorta arises as the immune response to introduction of an unknown anti-gene. At the same time infiltration of an aortal wall macrophages develops, In - and T-lymphocytes, production of tsitokin amplifies, proteolytic activity increases. The cascade of these reactions, in turn, leads to degradation of an ekstratsellyulyarny matriks on average an aorta cover layer that is shown in increase in content of collagen and reduction of elastin. On the place of gladkomyshechny cages and elastichesky membranes kistopodobny cavities are formed owing to what durability of a wall of an aorta decreases.
Inflammatory and degenerate changes are followed by a thickening of walls of an anevrizmatichesky bag, developing of intensive perianevrizmatichesky and postanevrizmatichesky fibrosis, an union and involvement of the bodies surrounding aneurism in inflammatory process.
Symptoms of aneurism of a belly aorta
At the uncomplicated course of aneurism of a belly aorta subjective symptoms of a disease are absent. In these cases of an aneurysm it can be diagnosed incidentally at a stomach palpation, performing ultrasonography, a X-ray analysis of an abdominal cavity, a diagnostic laparoscopy concerning other abdominal pathology.
As the most typical clinical displays of aneurism of a belly aorta serve constants or the periodic aching, dull aches in a mezogastriya or the left half of a stomach that is connected with pressure of the growing aneurism upon nervous backs and textures in retroperitoneal space. Pains quite often irradiate to the lumbar, sacral or inguinal area. Sometimes pains have so intensive character that their knocking over requires purpose of analgetics. The pain syndrome can be regarded as an attack of renal colic, sharp pancreatitis or radiculitis.
Part of patients in the absence of pains notes feeling of weight, a raspiraniye in a stomach or the strengthened pulsation. Owing to a mechanical sdavleniye nausea, an eructation, vomiting, a meteorizm, locks can arise aneurism of a belly aorta of a stomach and a 12-perstny gut.
The urological syndrome at aneurism of a belly aorta can be caused by a compression of a mochetochnik, shift of a kidney and is shown by a gematuriya, dizurichesky frustration. In certain cases the sdavleniye of testicular veins and arteries is followed by development of painful simptomokompleks in testicles and the varikotsel.
The Ishioradikulyarny simptomokompleks is connected with a compression of nervous backs of a spinal cord or vertebras. It is characterized by waist pains, sensitive and motive frustration in the lower extremities.
At aneurism of a belly aorta the chronic ischemia of the lower extremities proceeding with the phenomena of the alternating lameness, trophic violations can develop.
The isolated stratified aneurism of a belly aorta meets extremely seldom; more often it is continuation of stratification of chest department of an aorta.
Symptoms of a rupture of aneurism
The rupture of aneurism of a belly aorta is followed by clinic of a sharp stomach and in rather short terms can lead to a tragic outcome.
The Simptomokompleks of a rupture of a belly aorta is followed by a characteristic triad: belly-ache and the lumbar area, a collapse strengthened by a pulsation in an abdominal cavity.
Features of clinic of a rupture of aneurism of a belly aorta are defined by the direction of a gap (in zabryushinny space, a free abdominal cavity, the lower hollow vein, a 12-perstny gut, a bladder).
The Zabryushinny rupture of aneurism of a belly aorta is characterized by a painful sindyorom of constant character. At spread of a zabryushinny hematoma to area of a small pelvis irradiation of pains in a hip, a groin, a crotch is noted. The high arrangement of a hematoma can feign kardialny pains. The amount of the blood which streamed in a free abdominal cavity at a zabryushinny rupture of aneurism, as a rule, is small – about 200 ml.
At vnutribryushinny localization of a rupture of aneurism of a belly aorta the clinic of a massive gemoperitoneum develops: quickly the phenomena of hemorrhagic shock - sharp pallor of integuments, cold sweat, weakness, threadlike, frequent pulse, hypotonia accrue. Sharp swelling and morbidity of a stomach in all departments, poured Shchetkin-Blyumberg's symptom is noted. Perkutorno is defined availability of free liquid in an abdominal cavity. The Letalyyony outcome at this type of a rupture of aneurism of a belly aorta comes very quickly.
The break of aneurism of a belly aorta in the lower hollow vein is followed by weakness, short wind, tachycardia; hypostases of the lower extremities are typical. Treat local symptoms to belly-ache and a waist, the pulsing education in a stomach over which sistolo-diastolic noise is listened. The specified symptoms accrue gradually, leading to a severe form of heart failure.
At a rupture of aneurism of a belly aorta the clinic of a profuzny gastrointestinal krovoteyocheniye with a sudden collapse, bloody vomiting, meleny develops in a 12-perstny gut. In the diagnostic plan it is difficult to distinguish this option of a gap from gastrointestinal bleedings of other etiology.
Diagnosis of aneurism of a belly aorta
In some cases the general survey, a palpation and an auskultation of a stomach allows to suspect existence of aneurism of a belly aorta. For identification of family forms of aneurism of a belly aorta it is necessary to collect the careful anamnesis.
At inspection of thin patients in a prone position the strengthened aneurism pulsation can be defined by a forward belly wall. At a palpation in the top part of a stomach the painless pulsing plotnoelastichesky education comes to light at the left. At an auskultation over aneurism of a belly aorta systolic noise is listened.
As the most available method of diagnosis of aneurism of a belly aorta serves the survey X-ray analysis of an abdominal cavity allowing to visualize a shadow of aneurism and its walls. Now in angiology UZDG, duplex scanning of a belly aorta and its branches is widely used. Accuracy of ultrasonic detection of aneurism of a belly aorta approaches 100%. By means of ultrasonography the condition of a wall of an aorta, prevalence and localization of aneurism, the place of a gap is defined.
Treatment of aneurism of a belly aorta
Detection of aneurism of a belly aorta serves as the absolute indication to surgical treatment. Radical type of operation is the resection of aneurism of a belly aorta with the subsequent replacement of the rezetsirovanny site gomotransplantaty. Operation is carried out through a laparotomichesky section. When involving in aneurism of podyovzdoshny arteries bifurcation aorto-podvzdoshny prosthetics is shown. The average lethality at open operation makes 3,8-8,2%.
Contraindications to planned operation serve recent (less than 1 month) a myocardial infarction, ONMK (up to 6 weeks), heavy warm and pulmonary insufficiency, a renal failure, widespread okklyuziruyushchy damage of podvzdoshny and femoral arteries. At an anguish or a rupture of aneurism of a belly aorta the resection is carried out according to vital indications.
Endoprosthesis replacement of an aorta by means of the implanted stent-graft belongs to modern low-traumatic methods of surgery of aneurism of a belly aorta. The surgical procedure is performed in X-ray operating room through a small section in a femoral artery; the course of operation is controlled by X-ray television. Installation of a stent-graft allows to isolate an anevrizmatichesky bag, having prevented thereby a possibility of its gap, and at the same time creates the new channel for a blood-groove. Advantages of endovascular intervention are the minimum injury, smaller risk of development of postoperative complications, bystry restoration. However, according to literature, in 10% of cases disteel migration of endovascular stent is noted.
Forecast and prevention of aneurism of a belly aorta
Aneurism of a belly aorta – artful and unpredictable vascular pathology. The probability of a lethal outcome from a rupture of aneurism of the big sizes makes more than 75%. At the same time from 30 to 50% of patients perish at a pre-hospital stage.
In recent years in a heart surgery considerable progress in diagnostics and treatment of aneurism of a belly aorta is observed: the number of diagnostic mistakes decreased, the contingent of the patients who are subject to surgical treatment extended. First of all, it is connected with application of the modern visualizing researches and introduction in practice of endoprosthesis replacement of aneurism of an aorta.
For prevention of potential threat of aneurism of a belly aorta, the persons having atherosclerosis or having the family anamnesis on this disease have to undergo regular inspections. An important role is played by refusal of unhealthy habits (smoking). The patients who transferred surgery concerning aneurism of a belly aorta need observation of the vascular surgeon, regular passing of ultrasonography and KT.