Acute aneurysm in myocardial infarction

A cardiac aneurysm is a localized bulging of a weakened area of the heart. It develops most often in acute aneurysms in myocardial infarction, less often caused by trauma, infection, congenital anomalies. In most patients, the problem acts as a complication of predominantly transmural infarction of the heart muscle. An acute aneurysm is spoken about if the development of pathology occurred during the first 14 days from the moment of myocardial infarction. [1]

Epidemiology

Myocardial infarctions occur more often in the morning. An attack is often preceded by severe mental shock or physical overload, fatigue or increased blood pressure. Acute aneurysm belongs to the category of early consequences of a heart attack, it can develop from the first hours of the onset of the attack. The frequency of development of such a complication is 15-20% (according to different data - from 9 to 34%), most often there is thinning and bulging of the left ventricle. Pathology is caused by extensive myocardial damage and is closely related to the background state of the body in the first few days after the infarction.

In general, the world statistics of cardiovascular pathologies does not add optimism: about seventeen million people die of heart disease every year. Up to 50-60 years of age, men are predominantly ill (5-7 times more often), and after 60 years of age the situation is equalized: both men and women are ill with approximately the same frequency. More extensive transmural infarcts are observed before the age of 40 years.

Mortality from acute aneurysms in myocardial infarction is very high and sometimes reaches 80-85%. On the background of conservative treatment for a five-year follow-up period, the survival rate was about 15-20%. [2]

Causes of the aneurysms in myocardial infarction.

The main cause of acute aneurysm formation is myocardial infarction itself. Predisposing factors are violations of the recommended regimen from the first day of the disease, concomitant high blood pressure, etc. Sometimes pathologic tissue changes can be caused by previously arisen causes:

• high physical exertion over a long period of time;
• A sustained, systematic increase in blood pressure readings;
• infections, especially syphilis, chronic tonsillitis, microbial endocarditis;
• external influences, trauma, including chest contusions, cardiac injuries, falls from heights, and motor vehicle accidents.

The most common cause of heart attack is atherosclerosis and blockage of coronary vessels by a blood clot or atherosclerotic growth (plaque). Less often the "culprits" are embolism or vascular spasm. [3]

Risk factors

Predisposing factors for the development of acute aneurysm and myocardial infarction include:

• systematically high blood pressure;
• elevated blood cholesterol;
• smoking, drug addiction, alcoholism;
• hypodynamia;
• diabetes, high blood sugar;
• overweight, abdominal obesity;
• hereditary predisposition;
• stress and severe emotional distress;
• in women, menopause;
• age after 60;
• infectious pathologies (syphilis, staphylococcal and streptococcal infection);
• Having angina;
• nutritional errors.

Pathogenesis

The formation of acute postinfarction aneurysm occurs in the acute period of myocardial infarction. The predisposing factors are mainly:

• lack of resting behavior;
• increased blood pressure in the acute period;
• the use of corticosteroid medications.

In the pathogenetic aspect, such forms of aneurysm are distinguished:

• Diffuse - represented by a zone of tissue scarring that gradually progresses to an area of normal heart muscle.
• Mesenteric - has a neck that widens to form a mesenteric cavity.
• Dissecting - formed as a result of endocardial damage, accompanied by the formation of a bursa in the thickness of the heart muscle under the epicardium.

In the vast majority of cases, an acute aneurysm forms in the anterior or anterolateral left ventricular wall or at the apex of the left ventricle. Thrombosis of the formed cavity is noted in 40% of cases. In the walls of the bursa there are inflammatory changes in the type of thromboendocarditis. In case of prolonged pathology, areas of calcinosis are detected. [4]

Symptoms of the aneurysms in myocardial infarction.

An acute aneurysm in myocardial infarction is characterized by the following symptoms:

• increasing weakness;
• respiratory disorders like cardiac asthma or pulmonary edema;
• a prolonged feverish state;
• increased sweating;
• irregular heart rhythm (shortening, increased heart rate, extrasystoles, blockages, atrial and ventricular fibrillations).

The first signs are often difficult to determine, since the acute aneurysm "hides" behind other coronary pathologies and is accompanied by the general symptomatology of cardiac disorders. [5] It is possible to appear:

• heart pain;
• discomfort behind the sternum;
• shortness of breath, palpitations;
• dizziness, fainting spells;
• peripheral edema;
• feelings of shortness of breath.

An acute aneurysm in myocardial infarction is diagnosed by a cardiologist.

Stages

Aneurysm in myocardial infarction can proceed differently, which depends on the stage of the pathological process:

• The acute stage is defined by a period of 14 days from the onset of the infarction;
• The subacute stage is defined by the period from 15 to 42 days after myocardial infarction, usually accompanied by the formation of scar tissue;
• Chronic stage has certain difficulties in the diagnostic plan, characterized by signs of acute heart failure.

Forms

Acute aneurysms in myocardial infarction may vary in configuration:

• Meshed (rounded, having a wide base of heart muscle).
• Mushroom-shaped (has a narrow neck against a fairly large bulge).
• Dissecting (characterized by multiple bulges in one area of myocardium).
• Diffuse (an elongated bulge and a cup-like depression in it are noted).

Structurally, they distinguish:

• A true acute aneurysm, which is an expansion of scarred or necrotized tissue on the myocardial wall;
• false aneurysm - a defect formed by myocardial damage;
• A functional aneurysm is a modified section of normal myocardium.

Complications and consequences

Since myocardial infarction itself is a pathologic process causing direct damage to a vital organ, an acute aneurysm already becomes a complication. Among other possible complications:

• stroke, recurrent heart attack;
• heart failure;
• heart rhythm disturbances;
• increased blood pressure;
• ventricular fibrillation;
• the aneurysm ruptured.

Ventricular fibrillation and rupture of the aneurysm in a short time can lead to the death of the patient, as they require emergency use of a ventilator and electric shock.

If other complications occur, drug therapy is prescribed to help restore heart rhythm and blood pressure. It is very important to adhere to strict bed rest, do not allow mental stress until persistent improvement of the condition.

Acute aneurysm in myocardial infarction is the most severe condition, which in a short time can lead to the death of the patient. Simultaneous development of other complications significantly worsen the survival prognosis. [6]

Diagnostics of the aneurysms in myocardial infarction.

Diagnosis of acute aneurysm in myocardial infarction is performed by a cardiologist. Diagnosis is made after examining the patient and obtaining information after all laboratory and instrumental studies. Timely and competently conducted diagnostic measures can avoid the most dangerous complications, including the prevention of lethal outcome.

The main methods of diagnosing an acute aneurysm are based on the determination of clinical and functional signs. After collecting anamnesis, the doctor prescribes general clinical blood and urine tests, which allows to identify concomitant pathologies that can affect the development and course of acute aneurysm.

Next, the patient requires traditional instrumental diagnostics:

• electrocardiography - helps to detect the pattern of myocardial infarction;
• magnetic resonance imaging - provides information about the location and size of the acute aneurysm;
• ultrasound - helps to visually examine pathologically altered areas, find out the configuration;
• EchoCG - allows you to determine the structural characteristics of the problem area, identify thrombi;
• Ventriculography - provides information on the location and size of the bulge, as well as the presence or absence of contractions in it.

ECG picture is nonspecific: persistent signs of acute transmural myocardial infarction are determined, arrhythmias (more often ventricular extrasystole) and conduction disorders (left bundle branch block) are possible.

The degree of cardiac muscle viability in the area of the pathologic bulge can be determined by stress echoCG and PET.

A complex and comprehensive diagnostic approach helps to find out all the details of the deformation of the affected tissues, and subsequently prescribe a clear and successful treatment. The patient should not refuse diagnosis, because this pathology does not tolerate delay: the risks of rupture of the thinning wall and subsequent lethal outcome are too great. [7]

Differential diagnosis

Differentiate acute aneurysm in myocardial infarction with such pathologies:

• Celomic pericardial cyst - often has an asymptomatic course and is detected only during prophylactic fluorography; may be accompanied by polymorphic nonspecific manifestations.
• Mitral heart defect - accompanied by overload of the left atrium and the small circle of blood circulation, manifested by dyspnea.
• Mediastinal tumor - may masquerade not only as an aneurysm, but also as bronchitis or pneumonia, and in the first stages is asymptomatic. It is detected when performing chest fluoroscopy, CT or MRI, positron emission tomography. Malignant tumor processes are prone to rapid enlargement, spread of metastases, often show a picture of compression of nearby organs and tissues.

Treatment of the aneurysms in myocardial infarction.

Conservative tactics do not completely get rid of acute aneurysms, so when such a diagnosis is made, the question of surgical treatment is necessarily raised. The main technique consists of surgical resection and suturing of the damage to the heart wall. Some patients are shown tissue reinforcement with polymer implants.

At the stage of preparing the patient for surgery prescribe drugs that normalize the processes of blood clotting, cardiac glycosides, means to stabilize blood pressure, conduct oxygen therapy, oxygenobarotherapy. Insist on the strictest bed rest. [8]

Relative contraindications to surgical treatment may include:

• Inability to administer the necessary anesthesia to the patient;
• The absence of normal viable heart muscle outside the aneurysm;
• low cardiac index.

Surgical treatment

The absolute indication for surgical intervention is a large acute aneurysm exceeding 22% of the left ventricular volume, as well as circulatory failure stage I-IIA.

The main goal of the operation is excision of the aneurysmal enlargement and revascularization of the heart muscle. The intervention is performed with artificial circulation.

The operation is performed in stages:

1. Dissect the aneurysmal bulge and open the left ventricular cavity.
2. The walls of the aneurysm are being dissected.
3. The left ventricular cavity is formed using the cicatricial suture method.
4. Endocardial stitching.
5. The cardiac wall is sutured with continuous sutures using gaskets.

Upon completion of surgical manipulations, air is removed from the heart cavities, circulation is started by removing the aortic clamp. After a few minutes, cardiac activity is restored. Additionally, vasopressor and inotropic agents, intra-aortic balloon counterpulsation may be used.

Among the most frequent complications of surgery is low ejection syndrome. The problem occurs as a result of a decrease in the volume of the left ventricular cavity. Ventricular arrhythmias and pulmonary insufficiency develop somewhat less frequently. [9] High-risk factors for the development of postoperative complications:

• old age;
• emergency surgery;
• simultaneous mitral valve replacement;
• initially unsatisfactory contractile activity of the heart muscle (EF less than 30%);
• increased intrapulmonary pressure;
• renal failure.

Prevention

The main preventive measures to prevent the development of acute cardiac aneurysms are to prevent myocardial infarction itself. Important points are the control of cholesterol levels, blood pressure and blood coagulation.

Other equally important principles include:

• nutritional correction with an increase in the share of consumption of vegetable products, seafood, avoiding fast food and convenience foods, confectionery and sausages, animal fats and large amounts of salt;
• weight control;
• Quitting smoking, alcohol and drug use;
• systematic check-ups with a family doctor;
• blood sugar control;
• after 40 years of age - prophylactic administration of acetylsalicylic acid (as prescribed by a doctor);
• reducing the impact of stress factors, ensuring adequate work, sleep and rest regimes.

Acute aneurysm in myocardial infarction is a severe threatening condition. Even after an attack, when the patient remains alive, his cardiac function deteriorates markedly, chronic heart failure develops. Only a competent approach of doctors and a radical change in lifestyle will prevent further development of unfavorable consequences.

Forecast

The prognosis for patients with acute aneurysm in myocardial infarction is ambiguous, as it depends on the patient's general state of health, timeliness and completeness of treatment procedures. If the aneurysm ruptures, the prognosis is significantly worsened. There is information that in recent years the lethality from this pathology has slightly decreased.

In prognostic terms, much is also related to the quality of cardiac rehabilitation aimed at improving cardiac function and quality of life of the patient. It is important to properly coordinate physical activity, control cholesterol and blood pressure, as well as body weight, minimize the influence of stress and other harmful factors. Many patients do not hurry to engage in therapeutic exercise, being sure that such activity will provoke a recurrence of the problem. However, it should be understood that the transferred acute aneurysm in myocardial infarction is an indication for a strictly necessary, but dosed physical activity. At the same time, it is necessary to stop smoking and drinking alcohol, adhere to a special diet, take medications prescribed by the attending doctor. Such tactics will help prevent the development of secondary cardiovascular pathologies.