Myocardial dystrophy: acute, fatty, ischemic, focal, in athletes

Myocardial dystrophy is considered a pathological process, which is based on the defeat of the heart muscle, resulting from metabolic and biochemical disorders.

In some sources, myocardial dystrophy is suggested not to be isolated into a separate pathology, but to be considered a clinical manifestation of a disease. However, this pathology, in comparison, for example, in cardiomyopathy, clearly delineates the processes occurring in the cardiac muscle.

Myocardial dystrophy is isolated only in the case when metabolic processes are proven to be damaged, as a result of which muscle damage occurs.

[1], [2], [3], [4]

Causes of the myocardial dystrophy

Already over a hundred years, there is a classification, which distinguishes two groups of causes of dystrophy of the heart muscle. It is based on various diseases that directly or indirectly affect the metabolic processes in the myocardium.

The causes of myocardial dystrophy of the first group include heart disease, in particular, myocarditis, ischemic disease and cardiomyopathy.

The second group indicates a non-cardiac pathology which, through hormones, blood elements or neural adjustment, can have a negative effect on the muscular layer.

This group includes anemia, when the level of erythrocytes and hemoglobin is lower than the permissible standards, tonsillitis in the chronic stage, intoxication, both internal and external, in particular professional poisoning.

In addition, the causes of this pathology imply a negative effect of drugs, the dose and duration of intake of which exceeded the permissible limits. This applies to hormonal drugs, cytostatics and antibacterial drugs.

Diseases of the endocrine organs, for example, the adrenal gland or thyroid gland, acting on the hormonal level, also contribute to the dystrophic processes in the heart muscle. Do not forget about chronic kidney disease and respiratory system.

Separately, it is necessary to distinguish sports dystrophy, when excessive physical exertion, which the heart muscle can not cope with, leads to its defeat.

Due to the above-mentioned causes, the muscle layer begins to lack energy. In addition, toxic substances formed as a result of metabolic processes accumulate in cardiomyocytes, which causes additional damage (endogenous intoxication).

Thus, the functional cells of the heart muscle die, in the place of which the foci of connective tissue are formed. It is worth noting that such areas are not capable of performing the functions of cardiomyocytes, resulting in "dead" zones.

Compensatory mechanism is an increase in the heart cavity, which causes a weak contractile process. In this case, the organs do not receive a full volume of nutrients and oxygen, and hypoxia increases. As the pathological process progresses, cardiac insufficiency arises.

[5], [6], [7], [8], [9],

Symptoms of the myocardial dystrophy

The pattern of clinical manifestations of pathology can vary significantly, ranging from complete absence of symptoms and ending with signs of heart failure with severe shortness of breath, edematous and hypotensive syndrome.

Symptoms of myocardial dystrophy are initially absent, but sometimes painful sensations in the heart are possible. They appear as a result of strong physical exertion or after a psychoemotional outburst, while at the same time the pain subsides.

At this stage, few people seek help from a doctor. In the future, dyspnea, swelling of the legs and feet is gradually added, which increases by the evening, pain attacks in the heart become more frequent, tachycardia, a disturbance in the rhythm of the heart and marked weakness.

All these symptoms already indicate the accession of heart failure, which worsens the prognosis for recovery.

In some cases, for example, with climacteric myocardial dystrophy, there are pains in the region of the heart, especially above the apex, which spread to the entire left side of the chest. Their character can be piercing, pressing or aching, and the intensity does not change after taking nitroglycerin.

Quite often, all these symptoms can be combined with other vegetative manifestations of menopause, such as redness of the face, a feeling of heat and increased sweating.

Alcoholic myodystrophy is characterized by the appearance of tachycardia, a feeling of lack of air and a cough. EKG can often observe extrasystole and atrial fibrillation.

Myocardial dystrophy in athletes

First we need to understand how the muscle cells work at rest and under load. So, cardiomyocytes even at rest operate at hollow power, but the heart contracts and relaxes from 60 to 90 times per minute.

When performing physical exercises, especially when running, the heart rate increases by 2 or more times. When the pulse reaches 200 per minute, the heart does not have time to relax to the fullest, that is, there is practically no diastole.

That is why myocardial dystrophy in athletes is due to the increase in the internal tension of the heart, as a result of which the blood circulates poorly and hypoxia develops.

With a shortage of oxygen, anaerobic glycolysis is activated, lactic acid is formed, and some organelles, including mitochondria, are destroyed. If the load exceeds the norm, the cardiomyocytes are almost in constant hypoxia, which leads to their necrosis.

Myocardial dystrophy in athletes develops by replacing the cells of the heart muscle with a connective tissue that is not capable of stretching. The athletes who suddenly died, at the autopsy found microinfarctions in the heart, which confirms poor blood circulation in the myocardium.

In addition, connective tissue poorly conducts nerve impulses, which can be manifested by arrhythmia and even cardiac arrest. Most often, death occurs at night after intensive training, the cause of which are microinfarctions as a result of improperly selected physical activity.

Forms

Ischemic myocardial dystrophy

As a result of short periods of insufficient supply of oxygen to the heart muscle, ischemic myocardial dystrophy can develop. However, one must take into account that at the time of ischemia, characteristic changes are recorded on the ECG, but at the same time, the markers of muscle damage are absent (transaminases, lactate dehydrogenases).

The pathogenetically muscular layer looks flabby, pale with areas of insufficient oxygen intake and edema. Sometimes a thrombus can be found in the arteries feeding the muscle of the heart.

When microscopic examination is characterized by vasoconstriction, in particular, the expansion of capillaries, stasis of erythrocytes and swelling of interstitial tissue. In some cases, hemorrhages and leukocyte diapedesis are noted, as well as groups of neutrophils in the peripheral region of myocardial ischemia.

In addition, muscle fibers lose their striation and glycogen stores. When staining, necrotic changes in cardiomyocytes are detected.

Of the clinical symptoms, it is necessary to distinguish angina - pain syndrome in the heart, a sense of lack of air, a sense of fear and increased pressure.

Complication can be acute heart failure, which in some cases is the cause of death.

[10]

Focal dystrophy of the myocardium

One of the forms of ischemic defeat of the heart is focal dystrophy of the myocardium. Morphologically it is the formation of small pathological foci of the heart muscle and is considered an intermediate form between angina and infarction.

The cause of the development of pathological foci is a violation of blood circulation in arteries feeding the muscle of the heart. Most often, people suffer from this pathology after 50 years. Pain sensations in the heart initially arise with intense physical exertion, but as progression - worry and at rest.

In addition to pain, a person may experience a feeling of inadequate inspiration and dizziness. Also a formidable condition is a disturbance of the rhythm and an increase in the frequency of contractions of the heart more than 300 per minute. Such tachycardias can lead to death.

There is also asymptomatic focal dystrophy of the myocardium, when a person does not experience any symptoms of pathology. In such people, even a heart attack can be painless.

To avoid the increase in symptoms, you need to see a doctor and conduct instrumental studies, such as ECG and ultrasound of the heart. Thus, it is possible to visualize lesions of the muscular layer and begin timely treatment.

[11], [12], [13], [14], [15], [16], [17]

Fatty degeneration of the myocardium

In some cases, among normal cardiomyocytes there appear those in which small droplets of fat accumulate. With the passage of time, the size of fatty inclusions gradually increases and eventually replaces the cytoplasm. This is how the fatty degeneration of the myocardium is formed.

In the cells of the heart muscle, mitochondria are destroyed, and at autopsy one can observe a different degree of expression of fatty heart damage.

An insignificant degree of activity of pathology can be visualized only with the help of a microscope, but a more pronounced lesion causes an increase in the size of the heart. At the same time, the cavities are stretched, the muscular layer is flabby, dull and clay-yellow in color.

Fatty degeneration of the myocardium is a sign of a de-symptomatic condition. As a result of the gradual accumulation of fatty inclusions in cardiomyocytes, there is a violation of the processes of cellular metabolism and the destruction of lipoproteins in the structures of the cardiac cell.

The main factors in the onset of fatty muscle damage are insufficient oxygen supply to the myocardium, pathology of metabolic processes as a result of an infectious disease, and unbalanced nutrition, where the level of vitamins and proteins is low.

[18], [19], [20], [21], [22], [23]

Myocardial dystrophy of the left ventricle

Lesion of the left ventricle is not an independent pathology, but is a manifestation or consequence of a disease.

Myocardial dystrophy of the left ventricle is characterized by a decrease in the thickness of the muscular layer, which causes the appearance of certain clinical symptoms. These include weakness, a sense of weakness, a violation of the rhythm of the heart, which is felt in the form of interruptions, as well as pain syndrome of varying intensity.

In addition, a person may be disturbed by shortness of breath while walking or exerting physical exertion, which reduces efficiency and increases fatigue.

In the course of further progression of dystrophy, edema of the shins and feet, the occurrence of palpitations and falling blood pressure may appear.

At laboratory research in blood the insufficient level of hemoglobin can be found out, that promotes development of an anemia.

Myocardial dystrophy of the left ventricle contributes to the dysfunction of other organs and systems. Without timely effective treatment, a pathological condition in the near future can lead to heart failure, which significantly worsens the general condition of a person.

As a result of strong physical overstrain in the myocardium, hemorrhages, necrotic processes and toxic damage to cardiomyocytes can be observed. Clinically, it can manifest a decrease in heart rate and a decrease in blood pressure.

Myocardial dystrophy in malnutrition can provoke the atrophy of muscle fibers, which is a consequence of pathological metabolism. Nitrous bases, bile acids and ammonium are found in the blood.

Manifestations of acidosis can be observed when this pathology is combined with diabetes mellitus. As for hyperthyroidism, it helps to weaken and reduce the thickness of the muscle layer. Parallel to this, the pressure and cardiac output increase.

Of complications, it is necessary to distinguish atrial fibrillation, noise during systole and the appearance of dilatation of the heart cavities. Later the pathological process progresses, and circulatory insufficiency is added.

Dyshormonal myocardial dystrophy

The defeat of the heart muscle as a result of imbalance of hormones is observed with dysfunction of the thyroid gland or due to a secondary hormonal disorder.

Dyshormonal dystrophy of the myocardium is more common after 45-55 years. In men, the pathology is associated with a violation of the secretion of testosterone, and in women - estrogens in the menopause or gynecological diseases.

Hormones affect the exchange of proteins and electrolytes in the cells of the heart muscle. With their help increases the content of copper, iron, glucose in the bloodstream. Estrogens activate the synthesis of fatty acids and contribute to the postponing of energy reserves for cardiomyocytes.

In view of the fact that this pathology can occur and progress fairly quickly, it is recommended that women during the menopause regularly perform a heart examination for early detection of the pathological process.

As for the thyroid gland, its function can be reduced or increased, which affects the metabolic processes in the muscle layer and the development of dystrophic processes.

Treatment of this type of pathology is to eliminate the cause of its development, namely the normalization of hormone levels and the restoration of normal functioning of endocrine organs.

With the help of medicines, a person can get rid of such clinical manifestations as a pain syndrome in the heart region of the pricking nature with spreading to the left arm, disruption of the heart (rapidity, slowing of the heartbeat and arrhythmia), and changes in the psychoemotional state.

In addition, a person may have irritability, increased nervousness, dizziness, sleep disturbance, and weight loss. Most often, these symptoms are inherent in thyrotoxicosis.

Myocardial damage due to an insufficient function of the thyroid gland can be manifested by aching pain in the heart with spreading to the left arm, deaf tones, swelling and a decrease in pressure.

[24], [25], [26]

Diagnostics of the myocardial dystrophy

Changes in cardiomyocytes and the muscle layer as a whole are a consequence of the progression of a disease. When referring to a doctor, his main task is to find the main pathology and to prescribe the right therapy for its treatment.

In the process of communicating with the patient, the first information about his complaints, the time of their occurrence and progression appears. In addition, the doctor during an objective examination can detect the visible clinical manifestations of the disease, especially when performing auscultation of the heart. It is especially necessary to ask about the diseases and sports that have been suffered, what to exclude or suspect the dystrophy of the myocardium of athletes.

Diagnosis of myocardial dystrophy also involves the use of instrumental methods. So, ultrasound of the thyroid gland can show its structure, and with the help of laboratory tests - determine the level of its hormones and evaluate functionality. Also, a clinical blood test may indicate an anemia if the hemoglobin level is low.

Particular importance is given to ECG, when rhythm disturbances are visualized, and pathology is not clinically manifested. Ultrasound helps detect changes in cardiac contractility and evaluate the ejection fraction. However, significant pathological foci can be seen only with severe heart failure. Ultrasound also indicates an increase in heart cavities and a change in the thickness of the myocardium.

Confirmation can be obtained after a biopsy, when a piece of muscle tissue is taken and carefully examined. This manipulation is very dangerous, therefore, for every suspicion of dystrophic processes it is impossible to use it.

A new method is nuclear MRI, when radioactive phosphorus is introduced into the body and its accumulation in the cells of the muscle layer is estimated. By the result, it is possible to judge the level of pathology. Thus, a reduced amount of phosphorus indicates insufficient energy reserves of the heart.

[27], [28], [29], [30], [31], [32], [33]

Treatment of the myocardial dystrophy

At an easy degree of a pathology and at absence of a heart failure patients can pass treatment of a dystrophia of a myocardium in the conditions of a polyclinic or in the conditions of a day hospital, it is obligatory under supervision of the doctor.

The main task is to identify and eliminate the cause that caused metabolic disturbances in cardiomyocytes. Successful treatment of the underlying disease provides complete regression of the dystrophic processes or a significant improvement in the clinical and morphological pattern.

With thyroid dysfunction, an endocrinologist should be consulted , which should adjust the treatment and prescribe hormonal means.

In the presence of anemia, iron preparations, vitamin complexes or erythropoietin should be used. Therapy of chronic tonsillitis is the use of antibacterial and anti-inflammatory drugs. If the effect is insufficient, it is recommended that the tonsillectomy is performed - a surgical operation to remove the tonsils.

Treatment also implies the effect on the trophic of the muscle layer. To this end, you can use cardiotropic drugs that will feed the heart muscle. They normalize metabolic processes and thereby improve the work of the heart. These include magnesium, potassium in the form of panangin and magneroth, vitamins of group B, C and folic acid. Its effect was proved by such medications as riboksin, retabolil and mildronate.

If the cause of pain in the heart is a psychoemotional load, it is recommended to use sedatives, such as corvalol, valerian, motherwort, barboval or novopassit.

In the presence of arrhythmias, calcium channel blockers in the form of verapamil, beta-blockers (metoprolol) or cordarone should be used. In the process of treatment, it is necessary to monitor the activity of the heart with the help of ECG. During the therapeutic course, heavy physical exertion should be avoided. After the disappearance of the clinical manifestations of the pathological process, even for a month, it is necessary to take cardiotropic drugs. This course should be repeated 2-3 times a year in the next 3-5 years.

Prevention

Based on the known causes of the pathology, the prevention of myocardial dystrophy should include measures to eliminate the leading disease, which has a negative effect on cardiomyocytes.

For preventive purposes, it is necessary to take vitamin and mineral complexes on a regular basis. However, do not forget about nutrition and rest. Also, stressful situations should be avoided in order to avoid disturbance of the psychoemotional state and dosage to engage in physical activity.

Training for athletes should be made taking into account gender, age and the presence of concomitant pathology in humans. An obligatory condition is the sanation of all chronic foci and control over the activity of already existing diseases.

Prophylaxis means using a minimum amount of drugs in strictly selected dosages. Failure to adhere to the regimen of drugs threatens to intoxication and damage to the muscle middle layer.

In the period of intensive loads, with menopause and in old age, it is necessary to undergo regular examinations to determine the work of the heart, even if performing an ECG and ultrasound.

[34], [35], [36], [37], [38], [39], [40]

Forecast

For each person depends on the prognosis of myocardial dystrophy, as a timely call to a doctor and a prompt start of treatment can provide a complete regression of the pathological process and the elimination of clinical manifestations.

However, in case of complications in the form of heart failure, the prognosis depends on the severity of the pathology and can have an unfavorable outcome. As a result of the lack of treatment, the general condition and quality of life of a person significantly deteriorates.

In advanced stages, sometimes even a heart transplant is required, since drugs can not independently cope with the dystrophic processes and their consequences.

Dystrophy of the myocardium is not detected so often in the absence of clinical symptoms at the initial stage. With the help of regular examinations and ECG and ultrasound of the heart, one can avoid further progression of pathology and activate the processes of restoring the normal structure of cardiomyocytes.

[41], [42], [43], [44]