Arterial aneurysm

Certain diseases or injuries can cause arteries to weaken and locally dilate, resulting in the formation of an arterial aneurysm. As this enlargement increases, the vascular wall can rupture, threatening massive internal bleeding and death. In general, the term arterial aneurysm refers to a bulge or balloon-shaped "bulging" of the arterial wall due to its weakness and thinning. [1]

Epidemiology

The risks of arterial aneurysms increase significantly with age. Thus, pathological enlargements are more often detected in patients over 45-50 years of age, and they are more common in men. Among other significant risk factors, experts consider smoking and frequent increase in blood pressure.

Most patients are asymptomatic, so an aneurysm is often talked about as a "time bomb". The patient may not realize that he has a problem for many years or decades, and learn about it accidentally during routine preventive diagnostics. But in many cases, the existence of pathology becomes known after the appearance of complications.

This diagnosis was fatal for many famous people - Albert Einstein, Charles de Gaulle, Robert Koch, Andrei Mironov.

Arterial dilation can have different characteristics and sizes. Thus, the altered diametral lumen of the aorta can be insignificant - up to 3 cm, medium - from 5 to 7 cm, and giant - exceeding the diameter of the infrarenal aortic section 8-10 times.

The only radical method of getting rid of pathology is surgical intervention.

Causes of the arterial aneurysm

It is still unknown to scientists why arterial aneurysm develops in some people in the presence of the same factors and not in others. However, the most probable reasons for the appearance of pathology have still managed to find out. Thus, experts point to the involvement of genetically conditioned vascular defects, various cardiovascular diseases, hypertension, congenital connective tissue pathologies, malignant and atherosclerotic processes, as well as trauma.

Aggravating factors can include:

• nicotine, drug and alcohol addictions;
• high blood cholesterol;
• frequent or profound psycho-emotional stress;
• Infectious and inflammatory diseases (microbial, fungal, viral origin).

Some experts talk about the provoking effect of prolonged use of certain medications - in particular, hormonal agents, oral contraceptives.

Risk factors

The appearance of arterial aneurysms is associated with loss of elasticity and strength of the vascular wall. Weakening of the artery can be associated with two categories of factors:

• Factors predisposing to the occurrence of arterial aneurysms:
  • unfavorable nuances of heredity, congenital anomalies affecting the arterial musculature (collagen type III deficiency) mainly at the sites of vascular bends, bifurcations, branches;
  • traumatic vascular injuries;
  • bacterial infections, mycoses, tumors causing the development of embolism;
  • radiation exposure;
  • atherosclerotic processes, vascular hyalinosis.
• Direct factors that become a trigger for the formation of pathologic dilation - in particular, high blood pressure.

Pathogenesis

The most common factor in the development of arterial aneurysms is considered to be atherosclerosis due to metabolic disorders, changes in the conversion of lipid fractions, fat imbalance. These pathological processes can have congenital, genetically determined or acquired origin - in particular, sometimes they are a consequence of liver damage, endocrine system and so on. In many patients, the problem is explained by nutritional disorders, which consist of an incorrect and irrational diet.

In addition to lipid imbalance and the development of atherosclerosis, damage to the arterial wall is also important, which can be associated with smoking, alcohol abuse, high blood pressure, diabetes mellitus.

It is important to realize that the development of arterial aneurysms can be affected by a variety of concomitant pathologies and factors - including insufficient physical activity, low thyroid function.

Arterial aneurysm can develop on almost any artery, so the pathology can be expressed in the lesion of coronary, cerebral, renal, peripheral vessels. In some cases, pathology is found not on one vessel, but affects several arterial directions.

The structure of an arterial aneurysm

An aneurysm is a limited area of pathologically enlarged artery, the walls of which are thinning. Accelerated vestibular troma formation is possible, and the risk of rupture of the vessel layers with the development of severe bleeding is significantly increased.

The structure of the aneurysm segment is divided into several sections: neck, body and dome. The neck consists of three layers, so its rupture is almost impossible: the neck is the strongest part of the arterial aneurysm. The dome, on the other hand, is the weakest and most vulnerable part, as it includes only one connective tissue layer, which is quite thin.

The normal arterial wall includes three layers. These are the inner endothelial wall (intima), smooth muscle layer (media) and outer connective tissue layer (adventitia). In the process of aneurysmal weakening and expansion of the vascular segment, the number of layers decreases: the inner smooth muscle membrane thins or disappears, the endothelium undergoes subintimal cell proliferation.

False arterial aneurysm

The term false arterial aneurysm essentially refers to a hematoma, or a limited area of hemorrhage in the perivascular space formed as a result of microdamage to an artery. A dense connective tissue capsule is formed around the hematoma, which resembles a continuation of the vessel wall.

In most cases, a false bulge has a traumatic origin (appears as a result of blunt trauma, dislocations, closed fractures, medical manipulations), but can also occur against the background of an existing true aneurysm.

"False" pathology in no way reduces the degree of its danger. Patients with false aneurysms often develop thromboembolic complications.

Symptoms of the arterial aneurysm

The vast majority of arterial aneurysm cases are asymptomatic, and the pathology is detected accidentally. During examination, a medical specialist may detect a pulsating formation, or listen to specific noises during auscultation. But in most patients, arterial aneurysms are diagnosed during instrumental studies - for example, computed tomography, magnetic resonance imaging or ultrasound.

First signs of coronary arterial aneurysm: [2]

• chest pain (angina-like);
• shortness of breath with physical activity;
• heart rhythm disturbances;
• lower body swelling.

Intracranial arterial aneurysms [3] manifest:

• headaches and dizziness;
• impaired memory and concentration;
• mental retardation;
• thought retardation, personality changes, decreased intelligence.

Signs of arterial aneurysms of the lower extremities: [4]

• soreness when walking, standing;
• cold sensation in the extremities;
• pallor, lividity of the feet, spastic muscle twitching.

A cerebral arterial aneurysm is accompanied by these symptoms:

• impaired tone of the facial muscles (predominantly unilateral);
• sharp headaches;
• pupil dilation;
• painful sensations in the eyes, the appearance of a shroud in front of the eyes (in front of one eye);
• areas of numbness;
• double vision;
• nausea, sometimes with vomiting;
• a blurring of consciousness;
• photophobia.

A pulmonary arterial trunk aneurysm manifests: [5]

• difficulty breathing, especially with physical activity;
• chest pains;
• coughing for no apparent reason;
• with a sudden hoarseness;
• general weakness, lethargy, excessive fatigue, decreased ability to work.

It should be understood that arterial aneurysms are still more often asymptomatic. In addition, in some cases, the primary symptomatology is due to the underlying pathology that caused the aneurysm. In most patients, the course of the disease is latent and is detected only during routine or background diagnostics.

Stages

Arterial aneurysmal dilation goes through several stages in its development:

1. The stage is asymptomatic (painless).
2. The pain stage.
3. Stage of complication development.

The third complicated stage, in turn, is divided into substages:

• the threatened breakup phase;
• dissection or arterial embolization;
• an arterial tear.

The course of giant arterial aneurysms

Giant aneurysms are defined when the area of abnormal dilation becomes so large that it exceeds the size of 25 mm for cerebral vessels and 70 mm for the aorta. The larger the diameter of the dilated area, the thinner the vascular walls, and the higher the risk of rupture. Giant aneurysms are relatively infrequent, but always require emergency surgical intervention, as the risk of rupture reaches and even exceeds 80-85%. Moreover, if such a rupture occurs, it is almost meaningless to talk about saving the patient.

The resection of a giant bulge is technically difficult, as there is a risk of massive blood loss. Only highly qualified specialists with considerable experience in performing such interventions should be involved in the operation. An important role is played by the availability of appropriate support, equipment, experienced anesthesiologists.

Complications and consequences

Complications of arterial aneurysms include a whole range of dangerous diseases and acute conditions. Detachment and rupture of the artery with subsequent massive internal bleeding are considered the most threatening of them. Patients with complications are taken to hospitals, being in severe shock. Unfortunately, in most cases it is impossible to save a patient with ruptured arterial aneurysm - up to 70-80% of patients die. Due to such disappointing statistics, doctors insist on surgical treatment of pathology before the onset of life-threatening complications.

However, the insidious thing is that until the moment of detachment and/or rupture of an arterial aneurysm, pathology often does not detect itself in any way, and a person may not even know about the existence of the problem. When the disease complicates, there are sharp severe irradiating pains, blood pressure drops, severe weakness, cold sweat, possible blurring and loss of consciousness. In such a situation, the chances for a favorable outcome are already extremely low, and only emergency surgical intervention performed by qualified specialists can help.

Diagnostics of the arterial aneurysm

In order to detect arterial aneurysms and choose the right therapeutic tactics, the doctor should ensure a complete diagnosis of the patient, with mandatory computed tomography, magnetic resonance imaging and X-ray contrast angiography. The results of the studies will help the neurologist and angiosurgeon to determine the optimal treatment method.

Instrumental diagnostics in the form of CT and MRI allow a quick assessment of the probability of rupture of the pathologic extension. The results can be obtained in just a few minutes, which is very important for decision making and urgent medical care of the patient. The MRI image usually visualizes the cause that may have led to changes in the vascular structure.

Angiography helps to accurately determine the location and extent of arterial damage, as well as to understand whether there is a need for surgical intervention. Probable "disadvantages" of this method are a certain complexity in performing the procedure, high frequency of allergies due to the introduction of contrast agent.

Tests are prescribed within the framework of general clinical laboratory diagnostics (general urine analysis, general blood analysis, biochemical blood analysis). Additionally, if indicated, it is possible to study lipid metabolism indicators: total cholesterol, LDL-C, HDL-C, apoprotein B, triglycerides, potassium, calcium, magnesium. If coronary arterial aneurysm is suspected, it is recommended to evaluate such markers as troponin, myoglobin, creatine phosphokinase, lactate dehydrogenase, C-reactive protein, indicators of the blood coagulation system (prothrombin, fibrinogen, D-dimer, antithrombin III, INR, ACTH).

Differential diagnosis

In aortic aneurysms, chest pain and difficulty in breathing are often the main symptoms. This picture is often and erroneously perceived as symptomatology of angina pectoris. However, unlike myocardial ischemia, pain in arterial aneurysm is associated with stretching of nerve fibers: it is less intense than in angina pectoris, but longer and does not disappear after taking Nitroglycerin. Often such complaints are heard along with cough, vocal hoarseness, discomfort when swallowing.

Infarction is usually suspected already at the time of thoracic aneurysm dissection, when there are sharp increasing chest pains, which are combined with high blood pressure. Acute arterial insufficiency with increasing heart failure may develop.

For the purpose of differential diagnosis, it is appropriate to perform:

• ECG (nonspecific changes in T and S-T segment are detected);
• echocardiography (in arterial aneurysm there is a dilated vessel bulb, increased thickness of the posterior and anterior wall of the aorta, there is a mobile element of the inner sheath in the arterial lumen);
• Radiography (chest examination shows a dilated upper mediastinum, lack of clarity of contours or expansion of the diameter of the aortic arch, doubling of the aortic contour, changes in the position of the trachea, widening of the cardiac contours).

The results of magnetic resonance imaging and computed tomography should make the final diagnosis.

Treatment of the arterial aneurysm

Therapeutic measures for arterial aneurysms can be medication and non-medication. The range of drugs used, although wide, is aimed not at eliminating the pathology as a whole, but at inhibiting the further development of aneurysmal expansion, preventing the emergence of complications and alleviating the patient's well-being. Such therapy is possible only in the early stages of aneurysm development, if there is no threat of unfavorable dynamics. Patients are constantly monitored indicators of lipidogram and blood coagulation, markers of hepatic performance. In addition to medication, diet modification, normalization of body weight, optimization of physical activity, getting rid of bad habits are necessarily added.

It is indicated to take drugs that affect blood coagulation processes and blood pressure. In acute rupture of a pathologically dilated vessel, epsilonaminocaproic acid is successfully used, which inhibits the fibrinolytic ability of the blood, which reduces the likelihood of recurrent hemorrhage. But the only radical way to eliminate arterial aneurysms is surgical intervention.

Surgical treatment

Arterial aneurysms can only be completely repaired by surgical correction. Absolute indications for surgery include:

• presence of a wide neck, or absence of an aneurysm neck (fusiform, sac-like fusiform, blister arterial aneurysms);
• severe atherosclerotic changes in the pathologically dilated area, or signs of thrombosis;
• Diverting vital arterial vessels away from the area of aneurysmal enlargement;
• signs of dissection, giant arterial aneurysm;
• localization of the pathological site in the vertebrobasilar basin, cavernous or clinoid section of the internal carotid artery, ophthalmic section of the internal carotid artery;
• insufficient collateral circulation in the area of efferent branches;
• The "surgical" origin of the aneurysm.

Surgical intervention is considered the only effective method of arterial aneurysm repair. In advance, the surgeon stipulates with the patient the most likely risks and complications of pathology, determines the optimal type of surgery, depending on the indications. Most often we are talking about these types of surgical intervention:

• Clipping. The operation involves the introduction of a special clip, by means of which the damaged segment of the artery is clamped. The procedure is effective, but does not protect against possible recurrence of pathology.
• Embolization. The method consists in blocking blood flow in the area of an arterial aneurysm by filling the lumen with a special spiral: as a result, the damaged segment gradually overgrows.

Prevention

Prophylactic recommendations to prevent the development of arterial aneurysms include:

• complete abstinence from bad habits (smoking, alcohol and drugs);
• Normalization of body weight (overweight contributes to the development of vascular complications, accompanied by metabolic disorders and reduced physical activity);
• nutritional correction (it is necessary to consume dishes with low salt and animal fats, with a predominance of vegetables, cereals, vegetable oils, nuts, greens, fermented milk products, seafood);
• correction of physical activity (physical activity should be started cautiously, based on the general state of health and age indicators, at the initial stages giving preference to walking and swimming).

It is equally important to visit doctors regularly, to carry out diagnostic preventive measures (physical examinations, laboratory tests).

Forecast

To prevent the development of complications, patients with arterial aneurysms are recommended to be regularly examined by such specialists as cardiologist, neurologist, therapist, endocrinologist. It is important to adopt a healthy lifestyle, adjust nutrition and physical activity, control cholesterol and blood glucose values, completely abandon bad habits.

Ignoring the problem, the lack of necessary comprehensive treatment significantly worsen the prognosis of arterial aneurysms. The risks of rupture of the pathological expansion or the appearance of thrombotic complications are significantly increased. If the aneurysm is detected in time, an operation is performed to eliminate it, the outcome of the pathology becomes much more optimistic.

Arterial aneurysm is a dangerous pathology that can complicate literally at any moment. To prevent this from happening, it is necessary to follow all medical recommendations, and if indicated, do not refuse surgical intervention.