Dilated cardiomyopathy is a dysfunction of the myocardium that leads to heart failure. Against the background of such a condition, dilatation of the ventricles along with systolic dysfunction predominates in the body. Symptoms of the development of dilated cardiomyopathy (ICD code 10 I42.0) include shortness of breath, and, in addition, fatigue with peripheral edema. The diagnosis is established on the basis of clinical data, radiography and echocardiography. Treatment of this diagnosis is aimed at eliminating the cause. It is not excluded the need for heart transplantation. In detail about what a pathology such as dilated cardiomyopathy is, what are the causes, symptoms, and also how its treatment is currently being carried out, we will describe further.
Epidemiology of the disease
The incidence of this pathology is five cases per hundred thousand people per year. In men, it occurs more often. The most dangerous period is between thirty and fifty years old. This disease also causes the development of chronic heart failure in thirty percent of cases. Among other types of cardiomyopathies, this variety is sixty percent. Next, consider what causes the ailment.
Causes of the disease
Dilated cardiomyopathy has many known and unrecognized causes. The most common is diffuse damage to the coronary artery with ischemic myopathy. More than twenty viruses are capable of causing this pathology. For example, in a temperate zone, the most common is Coxsackie virus, and in America, Chagas disease is a common cause. This disease is increasingly common among people who have AIDS. Some causes include the presence of toxoplasmosis and thyrotoxicosis. Various toxic substances, in particular alcohol, along with organic solvents and certain chemotherapeutic drugs, for example, Doxorubicin, can cause heart damage.
For the most part, the etiology of dilated cardiomyopathy (code according to ICD-10 I42.0) is unknown, but in the development of its primary form, at present, much attention is paid to the following three points:
- Family and genetic factors.
- The transferred myocarditis virus.
- Immunological disorders.
According to genetic studies, with the development of the idiopathic form of the disease in one third of cases, a family predisposition is determined, against which autosomal, dominant and recessive inheritance prevails. Specialists characterize autosomal and dominant forms by genetic heterogeneity and clinical variability. The mitochondrial form is associated with abnormalities and dysfunction of the phosphorylation process. Due to the mutation, a violation of the energy metabolism of cardiomyocytes occurs, which leads to the development of this disease. Many myopathies are associated with neurological disorders.
We continue to consider the causes of dilated cardiomyopathy.
Of great importance, among other things, is the role of enteroviral infections. Persistent viruses damage mitochondria and disrupt cellular energy metabolism. It is likely that people who are sick with initial autoimmune deficiency are more exposed to the damaging effects of viruses and the subsequent development of the disease.
It is suggested that in some patients, dilated cardiomyopathy begins with myocarditis, which is accompanied by a variable phase. Against the background of this phase, necrosis forms, and then chronic fibrosis occurs. Regardless of the reasons, the myocardium becomes thinner, wider and hypertrophied, which often leads to the expansion of the atria. In most patients, the disease affects both ventricles at once. It happens that only the left ventricle suffers.
As soon as the expansion of the heart chambers reaches a significant size, especially against the background of the acute phase of myocarditis, the formation of parietal thrombi often occurs. Arrhythmias can complicate the course of myocarditis and the late phase of dilatation. The development of atrioventricular block is not excluded. As a result of dilatation of the left atrium, atrial fibrillation can occur.
Why does secondary dilated cardiomyopathy occur?
The main causes of the secondary form of pathology
The main causes of the development of the secondary form of the disease include:
- Presence of hypokalemia, hypophosphatemia, or uremia.
- The appearance of endocrine disorders.
- The presence of diabetes.
- The development of hypothyroidism.
- The patient has pheochromocytoma.
- Prolonged arterial hypertension.
- The presence of coronary heart disease.
- The appearance of infectious, bacterial, fungal, viral or parasitic diseases.
- The development of amyloidosis, hemochromatosis, or sarcoidosis.
- The appearance of neuromuscular pathologies.
- Malnutrition.
- Lack of selenium, carnitine and thiamine in the body.
- The development of rheumatic diseases.
- The presence of giant cell arteritis.
- The development of systemic scleroderma.
- The appearance of systemic lupus erythematosus.
- Exposure to the body of toxins, antiviral or chemotherapeutic drugs.
- Exposure to carbon monoxide, radiation, and cobalt, lead, or mercury.
- Exposure of cocaine or ethanol to the body.
- The presence of congenital or acquired heart defects.
Pathogenesis of the disease
As a result of the action of etiological factors on the heart with a diagnosis of dilated cardiomyopathy, cardiomyocytes are damaged and the number of functioning myofibrils decreases. This leads to the progression of heart failure, which is expressed in a significant decrease in myocardial contractile functions with the subsequent development of dilatation. As a result of pathological processes, a critical decrease in the pumping functions of the heart occurs, diastolic pressure in the ventricles increases and myogenic dilatation with tricuspid valve insufficiency is formed. Increased activation of the neurohormonal system of the body leads to significant damage to the myocardium and disorders of the blood coagulation system with the subsequent development of blood clots and thromboembolic complications. Now we find out what are the symptoms of the described pathology.
Dilated cardiomyopathy in children
Pathology is often found in babies, and it mainly occurs against the background of other heart diseases. The peculiarity is that the disease proceeds gradually, so parents go to the doctor when the problem begins to pose a serious threat to the health and life of the child. In infants, the problem can be manifested in insufficiently rapid weight gain and difficulties in the feeding process, in particular, inability to suckle for a long time due to lack of oxygen. As they grow older, adult-specific symptoms develop, such as chronic fatigue without objective reasons, ascites and swelling of the lower extremities, coughing with moisture, and frequent cases of lack of air (especially at night).
The danger of the disease lies in the fact that at any time there is a chance that a blood clot in one of the large arteries will come off the wall and provoke a heart attack of the kidney or lung or a stroke. Avoid this development of events will allow regular monitoring by a pediatric cardiologist in the presence of any cardiovascular pathology.
Symptoms of the disease
The disease often occurs in people at a young or middle age. The onset is usually gradual, with the exception of cases of acute myocarditis. Symptoms depend on which particular ventricle is affected. Left ventricular dysfunction provokes shortness of breath in patients on the background of physical activity along with fatigue due to increased diastolic pressure and low cardiac output. Insufficiency of the right ventricle leads to the appearance of peripheral edema and swelling of veins in the neck. For isolated lesions, the development of atrial arrhythmia and the onset of sudden death due to malignant ventricular tachyarrhythmia are typical. About twenty-five percent of all patients with this diagnosis report the presence of atypical chest pain. Signs of dilated cardiomyopathy can be difficult to recognize.
In the early stages, only certain symptoms of heart failure are determined. Against the background of progression of left ventricular failure, shortness of breath occurs along with asthma attacks, rapid fatigue and muscle weakness. In the presence of cardiac auscultation, tachycardia is detected. In fifty percent of cases, pathology is complicated by the development of ventricular arrhythmias. In twenty percent of cases, paroxysmal atrial fibrillation develops, turning into permanent, which significantly increases the risk of thromboembolic complications due to systolic myocardial dysfunctions.
Signs of right ventricular failure are the appearance of swelling of the legs, heaviness in the right hypochondrium, an increase in the liver and abdomen. Thus, symptoms of dilated cardiomyopathy range from mild symptoms to severe heart failure.
Disease classification
According to the official classification, the following forms of this disease are distinguished: idiopathic, familial, viral, alcoholic, and, in addition, specific cardiomyopathies that form against the background of any other heart diseases and systemic processes. There is also a classification according to which all cases of this disease are divided into the following two groups:
- Primary group. In this case, we are talking about genetic, non-genetic or acquired forms of the disease, in which the myocardium is mainly affected.
- Secondary group (the presence of various systemic diseases).
To determine the causes of the disease and its subsequent treatment, there are currently many different diagnostic methods. Let's consider them further.
What is the diagnosis of dilated cardiomyopathy?
Diagnostics
Diagnosis of the disease is based on an anamnesis, a physical examination and the exclusion of other causes of ventricular failure (for example, systemic arterial hypertension, primary valve disorders). Thus, chest x-ray, electrocardiogram and echocardiography are required. In the case of acute symptoms or pain in the chest, the determination of a cardiospecific marker is required.
An elevated troponin content is typical for coronary artery disease, but this also happens with heart failure, especially with a decrease in renal function. Among other things, ferritin content and iron binding ability should be investigated. Also, in order to identify the causes, the concentration of thyroid-stimulating hormones is determined and serological testing for toxoplasma and Coxsackie virus is performed.
Thanks to the electrocardiogram, sinus tachycardia is detected. Sometimes in the chest leads there are pathological teeth simulating myocardial infarction. Blockade of the bundle of the bundle is often detected.
On a chest x-ray, cardiomegaly is detected with an increase in all heart chambers. The presence of pleural effusion, especially on the right, often accompanies an increase in pulmonary pressure with interstitial edema. An echocardiogram can reflect the expansion and hypokinesis of the heart chambers, excluding the primary valvular disorder. Focal violation of the motion of the heart wall is typical, as a rule, for myocardial infarction, but also with dilated cardiomyopathy. This is possible, since the process may turn out to be focal. Echocardiography demonstrates the presence or absence of a blood clot in the chambers. Magnetic resonance imaging, as a rule, is not performed, but it can be used to display in detail the structure and functions of the myocardium. If the patient has cardiomyopathy, magnetic resonance imaging can reveal the pathological structure of myocardial tissue.
Coronary angiography is prescribed if the diagnosis in doctors is in doubt after a non-invasive study. In particular, coronary angiography is prescribed for patients with chest pain and elderly people who are likely to have coronary artery disease. The obstructive changes in the coronary artery that are detected by angiography are probably not the cause of dilated cardiomyopathy. During catheterization, a biopsy of the walls of any ventricle is sometimes performed. But more often it is not performed, since the effectiveness is usually low, and the pathological process may turn out to be focal, and the results of the biopsy will not affect the treatment in any way. Next, we find out how the treatment of dilated cardiomyopathy is carried out in modern conditions.
Disease treatment
Disposable primary causes in the form of toxoplasmosis, hemochromatosis or thyrotoxicosis must be corrected. Otherwise, treatment is prescribed as in heart failure, namely, patients are prescribed inhibitors and beta-blockers along with aldosterone receptor blockers, diuretics, and so on. Glucocorticoids with Azathioprine and equine antithymocyte globulin are no longer used. True, these drugs can reduce the acute phase of inflammatory cardiomyopathy, for example, viral myocarditis. It should be noted that such drugs do not contribute to the improvement of the long-term result. Antiviral drugs for the treatment of dilated cardiomyopathy are ineffective.
Given the fact that intracavitary thrombi can form, doctors use the prophylactic prescription of anticoagulants inside. This is done primarily to prevent systemic or pulmonary embolism, however, there are no controlled studies confirming the effectiveness of such therapy.
Clinical recommendations for dilated cardiomyopathy should be strictly followed. Severe arrhythmia is treated with antiarrhythmic drugs. Against the background of a blockade in the chronic phase, a permanent pacemaker may be needed. In the event that the patient has severe clinical manifestations, it is advisable to consider the possibility of biventricular stimulation.
The prognosis of dilated cardiomyopathy is presented below.
Disease prognosis
In general, the course of this disease is unfavorable, as the ten-year survival rate is from about fifteen to thirty percent. The average life expectancy of a patient after the onset of symptoms of heart failure, as a rule, is about five years. The death of a sick person in most situations occurs due to ventricular fibrillation, and chronic heart failure or massive pulmonary thromboembolism may also be the cause of death.
Given that the prognosis for dilated cardiomyopathy is extremely pessimistic, patients are often candidates for heart transplantation. Since there are very few hearts for transplantation, priority is given to younger patients who are under sixty years old.
Disability is possible with dilated cardiomyopathy, the criteria for which are:
- the presence of risk factors for sudden death;
- variant and form of the course of the disease;
- the severity of concomitant diseases;
- the effectiveness of therapy;
- severity of complications;
- profession, education and qualification of the patient, especially the nature and working conditions.
Disease prevention
Patients who are at risk of developing this pathology should in every way avoid professional sports, and, in addition, the choice of professions that are associated with overload. It is worth mentioning that the risk group includes people whose relatives include people with severe heart failure at a young age.
If dilated cardiomyopathy is detected in patients, the main task will be to prevent the progression of heart failure. We will name the main directions for assessing risk factors:
- Conducting a survey.
- Performing psychological testing to determine the level of anxiety.
- Health Assessment. In this case, the functional state of the alleged patients and the clinical manifestations of a possible pathology are analyzed.
- Monitoring risks that affect health.
- Assessing the effectiveness of preventive interventions and treatment. . , , .
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