Aneurysm of the abdominal aorta is a partial local expansion of the aortic lumen in the peritoneal region, the cause of which may be a congenital anomaly of the structure of the blood vessel walls, or their pathological changes.
This pathology leads among all cases of aneurysmal diseases of the blood vessels. Its frequency is almost 95%. In this case, mainly men over 60 years of age suffer from the disease. Female representatives are exposed to this disease much less frequently.
The danger of the disease is that it is often asymptomatic. But gradually the size of the aneurysm increases (annually - approximately 10-12%). As a result, the walls of the aorta are so stretched that they can just burst at any moment. The consequence of breaking the aneurysm is intense internal bleeding, and then - the death of the patient.
Causes of aneurysm and damaging factors
It is extremely important to determine the causes of the development of the formation of an aneurysmal sac, since 50-60% of all patients die from the disease. At the same time between the identification of pathology and the onset of death takes place quite a bit of time - only 1-2 years. Causes of vascular wall deformity can be inflammatory and non-inflammatory.
- With a non-inflammatory origin of pathology, atherosclerotic disease becomes the cause of its development in a large number of cases. It is characterized by the formation of cholesterol plaques on the walls of blood vessels, under the influence of which there is a change in the structure of the lining layer. Gradually, the tissues of the vascular wall are replaced by connective tissue structures, which makes it less elastic and more susceptible to deformation under the influence of blood pressure. Arterial hypertension, which has a close relationship with atherosclerotic processes, can also lead to the expansion of the aorta.
- Rarely, but still, there is a traumatic form of aneurysm. It occurs as a result of closed injuries of the chest, abdomen or spine. It may be the result of an accident, when the victim severely hits or rests against the steering wheel with his stomach or chest. Increases the risk of developing the disease and a fall from a height, as well as fragmentation, knife or other injury to the abdomen. Under such circumstances, all layers of aortic tissues are damaged, as a result of which a hematoma begins to form in them. Then the process of scarring of the wall occurs, and only after that, at the site of scar formation, an aneurysmal rupture can occur.
- Inflammatory. First of all, this group includes aneurysms of syphilitic etiology. Under such conditions, the inflammatory process first develops in the vessels feeding the aorta. After that, the aortic wall itself is affected, as a result of which its normal structure is disturbed. It is at the site of the lesion that the aneurysmal bag forms.
- A specific inflammatory aneurysm may develop due to tuberculosis or rheumatism. In this case, the pathological process from the spine or other foci of inflammation passes to the aorta, which leads to a protrusion of the arterial wall.
- Nonspecific inflammatory aneurysms develop on the background of various infectious processes that affect the human body. The pathogen enters the aorta along with the bloodstream, and can cause inflammation not only in it, but also in adjacent blood vessels. This aneurysm is called infectious-embolic. Pathogens can enter the abdominal aorta from the lungs, intestines, pancreas (for pancreatitis) and other organs.
Of particular importance is the anatomical gradation of abdominal aortic aneurysms. By this criterion, the disease can be infrarenal (when the aneurysm is located below the branch of the renal arteries) and suprarenal (when the focus of the pathological process is above the renal arteries).
According to the classification of aneurysms in the form of protrusion of the aortic wall, they are:
- diffuse spindles;
According to the structure of the aneurysmal wall, such formations are divided into true and false.
There is a classification of aneurysms and etiology (origin). Such a gradation divides the pathological process into innate and acquired. The second group may be of non-inflammatory origin, and may result from injuries, atherosclerosis, syphilis, infectious diseases, etc.
According to the clinical course of aneurysm, the abdominal aorta is divided into uncomplicated and complicated. By their size aneurysmatic bags are:
- small (from 3 to 5 cm);
- medium (from 5 to 7 cm);
- large (more than 7 cm);
- giant, the diameter of which is 8-10 times the diameter of the infrarenal aortic region.
There is a classification of aneurysms and the prevalence, according to which there are 4 types of pathological process:
- The first type is called infrarenal aneurysm with a distal and proximal isthmus sufficiently long.
- In the second type of infrarenal aneurysm, the proximal isthmus has a sufficient length, and the pathological process extends to the aortic bifurcation.
- In the third type of infrarenal aneurysm, aortic and iliac arteries bifurcation is involved in the pathological process.
- In the last, fourth type, we are talking about infra-and suprarenal aneurysm of the abdominal aorta.
Symptoms of abdominal aortic aneurysm
Often, the pathology does not manifest itself, and is detected only when performing x-ray, ultrasound, palpation or laparoscopic examination of the abdominal cavity.
But sometimes the disease, nevertheless, can manifest itself with the following symptoms:
- pain in the abdomen;
- a feeling of fullness and heaviness in the abdomen;
- sensation of pulsation at the site of localization of the lesion of the pathological process.
Often the source of the pain is in the left side of the abdomen. It can be mild, but sometimes it can become unbearable, which is why the patient has to put painkillers.
The pains can radiate to different parts of the abdomen, to the lower back, and also to the groin area. In this regard, patients are often given false diagnoses - radiculitis, pancreatitis, renal colic, etc.
As it grows, the aneurysm begins to put pressure on the walls of the stomach and duodenum. This leads to unpleasant symptoms, manifested by:
- belching air;
- bloating and flatulence;
- frequent constipation.
In some cases, aneurysm leads to a displacement of the kidney and squeezing of the ureter. This causes the appearance of diuretic symptoms and the development of hematuria. When squeezing the aneurysm of the veins and arteries in men there are painful sensations in the testicles, in parallel with which the development of varicocele.
When squeezing the spinal roots with an increasing aneurysm, an isio-radial symptom complex develops, accompanied by persistent pain in the spine, and motor and sensory disorders in the legs.
With this disease, the development of chronic disorders of the blood circulation process in the vessels of the legs can occur, which, in turn, causes trophic disorders and intermittent claudication.
If the aneurysm ruptures in the aorta region, the patient has intense bleeding that can lead to death in seconds. This pathological condition is accompanied by:
- sudden attack of acute, burning pain in the abdomen and / or lower segment of the spine;
- a sharp attack of hypotension, leading to the development of collapse;
- pulsating sensations in the peritoneum.
The clinical manifestations of aortic aneurysm rupture of the abdominal cavity depend on the direction of bleeding. So, with retroperitoneal bleeding, the occurrence of severe pain, characterized by a considerable duration. If the hematoma begins to spread to the pelvic organs, the patient complains of pain in the groin, perineum, genitals, and hips. Extensive hematoma lesions of the internal organs are often masked as clinical manifestations of a heart attack.
When intraperitoneal rupture of the aneurysm occurs the development of a massive homeoperitoneum, which is characterized by the occurrence of intense pain and abdominal distention. In all its segments, the occurrence of Shchetkin-Blumberg symptom is noted. The percussion method in the abdominal cavity reveals the presence of free fluid.
Along with the signs of an acute abdomen, symptoms of the following forms are characteristic of rupture of the aneurysmal sac:
- sudden blanching of the epidermis and mucous membranes;
- strong breakdown;
- the appearance of cold sweat;
- physical and mental retardation;
- frequent thready pulse;
- severe hypotension;
- reduce the number of allocated daily urine.
When aneurysm ruptures in the region of the inferior vena cava, arterio-venous fistula develops. This process is accompanied by:
- pain in the abdomen and lower back;
- the formation of a tumor in the peritoneal cavity above which systolic-diastolic murmurs are clearly audible;
- swelling of the legs;
- increased heart rate and pulse;
- aggravated dyspnea;
- pronounced loss of strength.
Heart failure gradually develops. With the increase of its symptoms may be fatal.
The rupture of the aneurysmal sac into the duodenum leads to the discovery of intense gastrointestinal bleeding. In this case, the patient may experience the following clinical manifestations:
- a sharp drop in blood pressure;
- discovery of bloody vomiting;
- strong breakdown;
It is very difficult to distinguish bleeding from rupture of an aneurysm from that in various gastrointestinal diseases (for example, GAL and duodenum).
If a pronounced clinical picture does not manifest itself, then the disease can be detected quite by chance, for example, with an abdominal ultrasound scan performed for another reason.
If symptoms occur, characteristic of an abdominal aortic aneurysm, first a thorough examination and questioning of the patient is carried out, after which the doctor directs him to laboratory and instrumental examinations. During the inspection, the pulsation of the abdominal wall is determined. The patient is in a lying position.
Mandatory event - listening to the abdominal cavity with a stethoscope to detect systolic noise in the projection of the aneurysm. During palpation, a tumor-like mass may appear. In the area of its localization, pulsation is often determined.
Of the diagnostic devices of the patient patients are often assigned to:
- Radiography of the abdominal cavity, which is informative in the formation of dehydrated calcium salts on the aneurysmal walls. In this case, in the picture you can see the protrusion of the aortic contours, which is normally not monitored.
- Angiography is a type of X-ray examination based on the use of a special contrast agent that is administered intravenously.
- MRI and CT are required to confirm or refute a preliminary diagnosis and determine the extent of aortic damage.
- Ultrasound and aortic DS. This is the most common diagnostic method to detect blood clots and atherosclerotic lesions in the aorta. With the help of these procedures, the blood flow in the affected part of the vessel is evaluated, and the extent of its damage by the pathological process is determined.
Great importance is attached to clinical tests: revmesis, blood test for sugar and cholesterol, general and biochemical blood tests.
If the diagnosis was confirmed, the patient must be registered for life with a phlebologist or cardiac surgeon. The only radical treatment for a disease is surgery. But it can not always be carried out, because:
- the procedure is very complicated and highly traumatic;
- there are large risks of postoperative complications, and even death;
- the operation is heavily tolerated by elderly patients and those who have concomitant diseases of the heart, brain or blood vessels that occur in a severe form;
- in almost 95-99% of cases, a lethal outcome occurs when aneurysm ruptures;
- surgery is expensive.
The main task of doctors in the treatment of such a serious disease is to choose the right tactics of therapy that does not harm the patient. Tips on this are as follows:
- Aneurysms of small size (up to 5 cm)not having a tendency to increase, or increasing in size by 0.3 cm in six months, are not operated. In this case, there is a dynamics of the progression of pathology.
- Large aneurysmal formations (from 6 to 10 cm and more), which are rapidly increasing within 6 months, should be immediately removed. Such formations threaten to break with all the ensuing consequences.
- Aneurysmal expansion, localized above the renal arteries, must be operated without the presence of strict indications (that is, despite the tendency to increase, or without one).
- Older patients older than 70 years old are dangerous to operate in any location and size of the aneurysm. This is especially true of patients who have comorbidities, characterized by a severe course. In this case, preference is given to conservative and observational therapeutic tactics.
A radical operative method of treatment of aneurysm is its removal with the subsequent replacement of the excised area with a special homograft. The intervention is performed through a laparotomy incision. If necessary, the iliac arteries can also be affected. Under such conditions, a bifurcation aorto-iliac prosthesis is performed. With an open surgical intervention, the mortality rate is from 3.8 to 8.2%.
Aneurysm excision is strictly contraindicated for:
- recent heart attack (less than 30 days);
- recent stroke (less than 1.5 months);
- severe cardiopulmonary failure;
- extensive occlusive lesion of the iliac and femoral arteries.
If there is a tear or rupture of the aneurysm, the operation is performed according to vital indications.
To date, the least traumatic method of radical treatment of the disease is aortic endoprosthetics using stent graft. The operation is performed in an x-ray operating room.
In the femoral artery, a minor incision is made through which the implant is inserted. Monitoring the progress of the procedure is carried out with the help of special x-ray television. Installing a stent graft provides isolation of the aneurysm, which helps to significantly reduce the risk of its rupture. In parallel with this, a new channel for blood flow is being created.
Despite all the advantages of such an operation, sometimes some complications are possible. In particular, this concerns the possibility of distal migration of endovascular stents.
Prognosis and prevention
If untreated, pathology predictions are very unfavorable. This is due to the high risk of complications that can lead to death.
- With a small aneurysmal bag size, the annual mortality rate is less than 5%. With sizes greater than 9 cm - 75%.
- Fatal outcome after detection of pathology with medium and large aneurysm during the first 2 years - 50-60%.
- When aneurysmal sac ruptures, mortality is 100%. After providing medical care after 2 months after surgery - 90%.
- With a timely operation, the forecasts are favorable. Survival in the next 5 years after the intervention is almost 65-70%.
In order to prevent a disease or to detect it in a timely manner, patients at risk need to have an ultrasound diagnosis every 6-12 months, and they should be examined by doctors. Of great importance is the refusal of smoking and alcohol, maintaining a healthy lifestyle and the complete cure of systemic, inflammatory or infectious pathologies.