False aneurysm

A false aneurysm (pseudoaneurysm, pulsating hematoma, PA) is a communication between the lumen of an artery and the adjacent connective tissue, which leads to the formation of a cavity filled with blood. The hematoma cavity does not contain the structures of the normal arterial wall (media and adventitia), which distinguishes it from a true aneurysm. The mechanism of PA formation is the resorption of a thrombus covering the puncture site. [ 1 ]

True and false aneurysms

Both true and false aneurysms have much in common – in particular, both pathologies manifest themselves almost identically. However, a true aneurysm is a pathological vascular expansion, spindle-shaped or saccular. A false aneurysm is the result of blood leakage after a vessel is damaged. In most cases, the patient’s history with pseudoaneurysm indicates catheterization, invasive vascular procedures, trauma, local inflammatory or tumor processes that can damage the arterial wall.

So, the main differences between the two pathologies are as follows:

1. A true aneurysm is an expansion of the vascular lumen, while a false aneurysm is an accumulation of blood outside the affected artery.
2. In both cases, pathological expansion of an already formed pathological focus is possible, but the false aneurysm does not rupture with such expansion.
3. The mortality rate from true aneurysms is much higher than that from false aneurysms.

[ 2 ], [ 3 ], [ 4 ], [ 5 ], [ 6 ], [ 7 ], [ 8 ]

Epidemiology

The most typical localization of a false aneurysm is the carotid artery, the vertebral artery (extra and intracranial). In general, the pathology can affect any arterial vessel - from the femoral artery (when performing coronary catheterization) to the vascular network of the abdominal cavity (with pancreatitis).

In most patients, a false aneurysm is formed from the adventitia, the thin outer vascular membrane, and the formed focus of hemorrhage.

Its frequency of development is from 0.1-0.2% in diagnostic coronary angiography and up to 0.5-6.3% (on average 1%) in case of PCI. The time of formation of the hemorrhage focus is from 14 days to 10 years, but most often the pathology develops within a month from the moment of vessel damage.

Men of middle and old age are more likely to get sick (ratio approximately 6:4).

Causes False aneurysm

A false aneurysm is in all cases the result of some damage to the vessel wall - that is, trauma, from the outside or from the inside.

Such damage can occur during medical procedures, such as angiography, when a doctor injects a contrast agent into a vessel using a special catheter. In such a situation, carelessness can lead to intravascular injury.

As purulent-inflammatory processes spread, they can also affect arterial vessels: their walls “melt” in the area of contact with the inflammation zone, blood flows out, and a hemorrhage site is formed.

It is also impossible to deny the possibility of microscopic damage to the artery during surgery, as well as as a result of external impacts. Often, the formation of false aneurysms is a consequence of traffic accidents, severe bruises, and sports injuries.

A false aneurysm can also form against the background of a true aneurysm: the vascular wall becomes thinner, microdamage occurs and, as a result, a hemorrhage site is formed.

[ 9 ], [ 10 ], [ 11 ], [ 12 ]

Risk factors

Risk factors for the development of a false aneurysm include the use of a larger diameter introducer, a combination of antithrombotic drugs, a longer procedure duration, difficulties in performing a femoral artery puncture, and the anatomical features of the patient.

The following factors also predispose to the development of a false aneurysm:

• performing surgical intervention on a vessel, medical catheterization (arterial manipulation using a catheter);
• blunt trauma - for example, a bruise from a traffic accident, a fall or a direct blow, during sports training;
• infectious and inflammatory process in the body;
• high blood pressure;
• tumor processes;
• uncontrolled or unjustified use of certain medications.

Pathogenesis

Hemorrhage occurs as a consequence of traumatic injuries or various pathological conditions. In an active pathological process, a blood vessel is damaged inside or outside, the accumulation of blood leads to compression of nearby tissues, structures, and individual organs suffer.

A false aneurysm can have different sizes. High blood pressure, long-term use of medications that affect blood clotting, and tumor processes play an unfavorable role in the development of the pathology.

The formation of false aneurysms in the brain is especially dangerous. The most common cause of this phenomenon is craniocerebral trauma, which causes a whole chain of disorders associated with brain function. Since the cranium is a strong bone structure, it is not able to stretch and change its volume. This entails the creation of excess pressure by the false aneurysm on the brain regions, cerebrospinal fluid and vascular network of the brain. This significantly worsens the patient's pathological condition.

All of the above processes are interconnected. The further outcome of a false aneurysm depends on the volume of the hematoma, its localization, and the presence of disorders in nearby structures, organs, and systems.

Symptoms False aneurysm

In most patients, a false aneurysm has few pronounced clinical manifestations, there is no profuse external bleeding, so the problem may remain unnoticed for a long time. The main symptom is a characteristic noise that increases with pulsation and can only be determined by auscultation.

For example, aortic false aneurysm manifests itself:

1. tachycardia;
2. dizziness, difficulty breathing;
3. chest pain;
4. short-term clouding of consciousness.

If the false aneurysm is small, there may be no symptoms at all. The clinical picture makes itself known when the hemorrhage site begins to press on nearby structures.

Ventricular aneurysm manifests itself:

• difficulty breathing, especially when lying down;
• rapid breathing;
• dry cough that does not bring relief;
• bluish skin;
• swelling of the legs;
• accumulation of fluid in the abdominal cavity.

With a false aneurysm of the femoral artery, the following may occur:

• pain sensations, with a tendency to increase with physical activity;
• sometimes – irradiation of pain to the groin area;
• pulsating sensation in the femoral artery area;
• numbness of the legs;
• convulsive twitching of muscles;
• bluish tint of the skin on the feet.

The first signs largely depend on the location of the false aneurysm. However, the most common symptoms in all cases are pulsation of the pathological focus and pain. Often, paleness and cyanosis of the skin are noted. [ 13 ]

Forms

A false aneurysm is in most cases traumatic and can affect different types of vessels. Depending on this, arterial, venous and combined arteriovenous false aneurysms are distinguished. There is also a classification depending on the localization of the pathological focus:

• A false aortic aneurysm can occur in the abdominal region, which runs through the lower part of the abdomen, or in the thoracic region, which is located in the chest.
• A false aneurysm of the femoral artery can affect any part of the vessel that is located in the area from the upper third of the thigh within the femoral triangle. The artery in the middle part of the thigh is covered by the sartorius muscle, and in the lower part it runs in the adductor canal.
• A false aneurysm of the heart (ventricle) is formed when the infarcted heart muscle is damaged and a cavity is formed within the pericardial adhesions. The left ventricle is usually affected, and its wall, enclosed in the surrounding pericardium, is ruptured. A false aneurysm of the left ventricle is usually located on its posterior surface (the anterior-septal part is a common location for a true aneurysm of the heart).
• A false aneurysm of the lower extremities can be detected in the aortoiliac, femoropopliteal or popliteal-tibial segment. Multiple (multi-level) lesions are often observed – for example, when a false aneurysm in the groin is not the only one, and similar foci are diagnosed along the entire length of the vessel. In most cases, the problem is detected in the popliteal fossa: a false aneurysm of the popliteal artery is one of the most common variants of such pathologies in the peripheral vascular network. The popliteal artery is a main vessel that runs from the lower thigh to the upper leg.

Complications and consequences

The outcome of a false aneurysm depends on the size of the formation, its tendency to increase, and the timeliness of seeking medical help. If the pathological process is not treated, various complications may arise, for example:

• rupture of a blood accumulation site with subsequent hemorrhage into the tissue;
• infection of the pathological focus, development of an infectious and inflammatory process with its further spread to the adjacent vascular wall;
• formation of a fistula with surrounding structures (tissues, organs);
• thrombus formation in the area of blood accumulation with subsequent entry of the clot into the circulatory system.

To avoid such complications, it is not recommended to delay visiting a doctor or ignore his or her prescriptions.

Diagnostics False aneurysm

Most patients with a false aneurysm at the initial stage are referred to a therapist or general practitioner rather than a neurologist or surgeon. If the doctor suspects vascular pathology, based on the complaints and other information collected, the patient is referred to a specialist for further diagnostics.

The neurologist evaluates the neurological status based on the indications (examines, checks reflex activity). Then prescribes laboratory tests:

• general clinical blood test with leukocyte formula (to assess the general condition of the hematopoietic system and the body as a whole);
• assessment of prothrombin, fibrinogen, antithrombin III indicators;
• assessment of the atherogenicity coefficient (total cholesterol and HDL), lipid profile indicators, and the main markers of atherosclerosis.

Blood is given in the morning on an empty stomach, while maintaining a drinking regime. No special preparation is required.

Instrumental diagnostics is most often represented by the following studies:

• Computer tomography – allows visualization of a false aneurysm, its volume and assessment of its impact on nearby structures. Based on the diagnostic results, a specialist can determine the tactics and volume of the upcoming treatment.
• Magnetic resonance imaging – helps to examine in detail the required area of soft tissue, especially when computed tomography is of low efficiency.
• Cerebral angiography (the procedure of choice for cerebral aneurysms), magnetic resonance angiography, CT angiography (helps to perform 3D modeling of cerebral vessels, assess the localization of the lesion in relation to vascular or bone structures).

Differential diagnosis

The main distinguishing features of a true and false aneurysm are:

• True aneurysm:
  • can develop in absolutely any artery, including the aorta, cerebral, coronary, and peripheral vessels;
  • occurs as a result of pathological changes such as atherosclerosis, infectious and inflammatory processes;
  • the aneurysmal wall has three layers, just like the vascular wall;
  • the enlargement of the aneurysm is accompanied by necrosis of muscle fibers.
• False aneurysm:
  • appears as a result of a defect in the vascular wall when it is damaged;
  • is a cavity located near a vessel;
  • the enlargement of the false aneurysm is accompanied by tissue necrosis due to compression of the arterial lumen.

Treatment False aneurysm

In the early stages of false aneurysm development, drug therapy may be sufficient. More radical surgical treatment is prescribed according to indications.

Among non-invasive (non-surgical) methods, ultrasound-guided compression and thrombin injection are particularly popular.

The ultrasound-guided compression method is suitable for patients with small false aneurysms. The surgeon uses a special ultrasound sensor and applies compression to the affected vessel segment in 10-minute cycles. Several such procedures may be required to achieve the desired therapeutic effect.

Thrombin injection allows for clotting of the blood inside the false aneurysm. The procedure is simple and rarely accompanied by complications. If such treatment is ineffective, or if the pathological formation is initially large, doctors, without wasting time on conservative treatment, immediately prescribe surgical intervention.

Medicines

Drug therapy is mainly aimed at eliminating existing symptoms and normalizing vital functions of the body. Drugs are prescribed to maintain normal blood pressure indicators: it is necessary to simultaneously maintain adequate blood circulation and prevent an increase in the volume of the false aneurysm. In addition, they affect the blood coagulation system, prevent and get rid of edema, and take measures to strengthen the vascular walls.

Blood pressure should not be reduced abruptly: gradual reduction continues until it reaches the age norm, and then it is maintained within the specified limits. This helps reduce the risk of continued bleeding and normalize blood flow.

Drug therapy is appropriate:

1. if the false aneurysm is small in size and does not exert significant pressure on nearby structures;
2. if the false aneurysm does not cause tissue displacement and is not accompanied by pronounced symptoms and neurological disorders.

The following medications may be used (according to indications):

• Calcium channel blockers (Nimodipine, 30-60 mg up to six times a day for a week) limit the entry of calcium ions into the cell and reduce the activation of apoptosis.
• Antihypoxants and antioxidants (Actovegin 1-2 tablets three times a day, Neurox in the form of intramuscular injections, Cytoflavin 2 tablets twice a day half an hour before meals) prevent the formation of free radicals, restore enzyme activity and antioxidant protection, improve glycolysis. In some cases, taking the drugs is accompanied by headaches, dizziness, tremors.
• NMDA receptor antagonists (Memantine, taken once daily in an individually adjusted dose) help improve brain function in cerebral false aneurysms.
• Blockers of the immune-inflammatory response (Cycloferon, 1 time per day, 450-600 mg per dose, half an hour before meals) increase the level of anti-inflammatory cytokines and prevent granulocyte adhesion.
• Cell membrane stabilizers (Asparkam 1-2 tablets three times a day, with caution - for patients with cholecystitis and hypotension).

Nimesulide, Diclofenac, Indomethacin, Ibuprofen, and Ketorolac are actively prescribed as painkillers.

Surgical treatment

Surgical intervention for false aneurysm is justified in most cases, since conservative methods are more appropriate only in the early stages of pathology development.

It is possible to use an open or closed (endovascular) surgical procedure: the choice is up to the surgeon and depends on the results of preoperative diagnostics. Open intervention involves the removal of the false aneurysm itself with subsequent vascular prosthetics or cannulation (as indicated). With a closed technique, intravascular removal of the pathological focus is performed.

The outcome of the operation depends on a number of factors, including the general health of the person, the severity of the clinical picture, the size of the false aneurysm and the extent of existing disorders. The mortality rate after surgical correction of coronary artery pseudoaneurysm is about 25%.

Prevention

Conventional prevention of false aneurysm formation involves maximum exclusion of factors that provoke it. Doctors recommend:

1. avoid injury and possible vascular damage;
2. control blood pressure;
3. give up bad habits (in particular, smoking);
4. learn to successfully overcome stressful situations;
5. Walk more often in the fresh air, avoid physical inactivity and excessive physical exertion.

A healthy lifestyle is relevant for people of any age. At the same time, you should pay close attention to your own health if you already have any pathologies. Unfortunately, many patients, knowing about their illnesses, ignore visits to cardiologists, endocrinologists, therapists, do not control blood pressure, cholesterol and glucose levels in the blood. However, it is important not only to lead an active and healthy lifestyle, eat right, but also to maintain your health with medication, following doctor's orders.

Forecast

Patients with chronic asymptomatic false aneurysms with a diameter of less than 30 mm and without increasing dynamics are treated conservatively. According to some statistics, against the background of drug treatment over four years of observation, only one fatal outcome was recorded out of ten patients, and in three cases there was the development of ischemic stroke.

Modern methods of treating false aneurysm show good results in most cases. After the completion of the treatment course, the patient should remain under the supervision of the attending physician for some time. In order to prevent thromboembolic complications, long-term use of anticoagulants is prescribed.

However, the most preferred method of treating a false aneurysm is surgery. The operation is especially recommended for patients with damage to two or more arteries, as well as coronary vessels.

The long-term prognosis depends on the size of the blood pool. Numerous studies prove that if there is a large false aneurysm, then there is a high probability that a person may develop other aneurysmal foci. Thus, relapses are more likely if the pseudoaneurysm has a diameter of 20 millimeters or more. An additional factor in possible relapse is thrombocytopenia.

Literature

• Shlyakhto, E. V. Cardiology: national guidelines / edited by E. V. Shlyakhto. - 2nd ed., revised and enlarged. - Moscow: GEOTAR-Media, 2021
• Cardiology according to Hurst. Volume 1, 2, 3. 2023