Cardiomyopathy is a change in the heart muscle of an often unexplained cause.
The condition for the diagnosis of ” cardiomyopathy ” is the absence (or the exception after the examination)
- congenital malformations,
- valvular heart disease
- damage caused by systemic vascular disease
- some rare variants of the defeat of the cardiac conduction system
Cardiomyopathies are primary when the pathological process affects only the heart, and secondary, developing as a result of any systemic disease.
There are three main types of damage to the muscle of the heart in cardiomyopathy , respectively, allocated
- dilated cardiomyopathy,
- hypertrophic cardiomyopathy
- restrictive cardiomyopathy.
Such a division is usually based on an assessment of the intracardiac circulation and, already at the initial stage of the disease, in some cases allows to establish the direction of the search for a possible cause of the process. With an unidentified root cause, the lesions speak of idiopathic forms of this or that cardiomyopathy.
For dilated cardiomyopathy is characterized by a violation of the contractile function of the heart muscle (myocardium) with a marked expansion of the heart chambers. Its occurrence is associated with genetic factors, since the family nature of the disease occurs. No less important are the observed impaired immune regulation.
Symptoms of dilated cardiomyopathy
Manifestations of dilated cardiomyopathy are determined by increasing heart failure:
- shortness of breath on exertion
- fast fatiguability,
- swelling in the legs,
- pale skin
- blue fingertips.
The prognosis for dilated cardiomyopathy is very serious. Joining atrial fibrillation worsens the prognosis. In the first 5 years of illness, up to 70% of patients die, although with regular, controlled drug therapy, it is undoubtedly possible to prolong the patient’s life.
Women with dilated cardiomyopathy should avoid pregnancy because the incidence of maternal mortality with this diagnosis is very high. In some cases, the provocative effect of pregnancy on the development of the disease.
Laboratory diagnosis provides little valuable data for diagnosis, but it is important to monitor the effectiveness of therapy in assessing the state of water-salt balance, to exclude some side effects of drugs, such as cytopenia.
The main instrumental method for the diagnosis of all types of cardiomyopathy is an ultrasound of the heart (echocardiography). In most cases, the instrumental diagnosis of dilated cardiomyopathy can be made at the first ultrasound examination.
The ECG does not have specific diagnostic criteria for dilated cardiomyopathy, however, various cardiac arrhythmias can be detected, including ventricular arrhythmias (better detected with daily Holter ECG monitoring ), signs of stress on the left ventricle.
Radiological is determined by an increase in the heart, and a little later signs of venous congestion in the lungs.
Coronary angiography – to exclude the ischemic causes of the expansion of the heart chambers.
Lifetime myocardial biopsy theoretically helps to exclude specific causes (viruses, amyloidosis ).
Diagnosis dilated cardiomyopathy – a diagnosis of exclusion. It is placed when all possible causes of cardiac abnormalities are excluded.
Treatment of dilated cardiomyopathy is aimed at combating heart failure, preventing complications. In the case of acquired DCM, treatment is directed to the main cause.
The main efforts in therapy are aimed at improving the contractile function of the myocardium and reducing the symptoms of heart failure with the help of ACE inhibitors. It is possible to use any of the drugs in this group, but wider than other currently used enalapril ( renitek , enap ).
In the presence of contraindications to the use of an ACE inhibitor, sartans ( valsartan , losartan ) are prescribed , which have the same properties.
The choice of a particular drug is determined by tolerability, blood pressure reaction, side effects.
An important place is occupied by the use of small doses of beta-blockers. Treatment begins with the lowest doses of the drug. If well tolerated, the dose can be increased by observing whether signs of heart failure are increasing.
The use of carvedilol, a beta-alpha blocker with a unique antioxidant effect on the myocardium unique to this group, is promising .
As with the treatment of heart failure caused by other diseases, the use of diuretics has traditionally been of great importance. Their effect is monitored by controlling the weight of the patient (preferably several times a week or daily), measuring the volume of urination, monitoring the electrolyte composition of the blood.
Due to poor prognosis of the disease, patients with dilated cardiomyopathy are considered candidates for a heart transplant.
Hypertrophic cardiomyopathy a disease characterized by a significant increase in the wall thickness of the left ventricle without expanding its cavity. Hypertrophic cardiomyopathy can be either congenital or acquired. The likely cause of the disease are genetic defects.
Symptoms of hypertrophic cardiomyopathy
Most often, the disease is asymptomatic or with minor symptoms. Many patients sometimes do not even suspect that they have a serious heart disease.
Manifestations of hypertrophic cardiomyopathy is determined by complaints of shortness of breath, chest pain, a tendency to fainting, palpitations.
Due to rhythm disturbances, patients often die suddenly. Hypertrophic cardiomyopathy is often found in young men who died during sports activities.
In some patients, heart failure gradually develops . Sometimes, especially in the elderly, circulatory failure develops suddenly after a long favorable course of the disease for many years.
As a result of the left ventricular relaxation disorder, a picture of heart failure is observed, although the contractility of the left ventricle remains at normal rates until the onset of the terminal stage of the disease.
The cause of circulatory disorders in hypertrophic cardiomyopathy is a decrease in the elongation of the chambers of the heart (especially the left ventricle). The left ventricle changes its shape, which is determined by the predominant localization of the site of thickening of the myocardium.
Laboratory and instrumental methods are used to examine a patient with suspected hypertrophic cardiomyopathy.
1. Routine laboratory diagnostics:
- complete blood count,
- cardiac enzymes – KFK, AST, ALT, LDG),
- blood lipids
- thyroid hormones,
- kidney and liver tests,
- uric acid.
All this allows to identify extracardiac conditions that can worsen the course of heart failure.
2. Blood test for brain natriuretic peptide level to assess the severity of heart failure. Its high rate clearly correlates with the severity of diastolic (relaxing) heart function.
An electrocardiogram is characterized primarily by signs of thickening of the left ventricle, as well as various cardiac arrhythmias.
Radiographically, the disease may not be detected for a long time, since the external contour of the heart does not change. Later signs of pulmonary hypertension appear.
Ultrasound of the heart (echocardiography) is a reliable method for early diagnosis of this disease, since it is able to detect a change in the internal outline of the cavity of the left ventricle.
Magnetic resonance imaging MRI of the heart is a more expensive method than ultrasound, but it has a higher resolution. Thanks to him, specialists receive a clearer picture and information about the structure of the organ.
Prognosis for hypertrophic cardiomyopathy
The prognosis of the disease is most favorable in comparison with other forms of cardiomyopathy.
Patients remain for a long time able to work (according to their profession). However, in such patients with an increased frequency, sudden deaths are recorded.
The clinic of heart failure is formed rather late. Joining atrial fibrillation worsens the prognosis. Pregnancy and childbirth with hypertrophic cardiomyopathy are possible.
Treatment is aimed at reducing the severity of symptoms of the disease, improving the quality of life of the patient and preventing attacks of sudden cardiac death and progression of the disease.
Verapamil or diltiazem is most commonly used. Beta-blockers are widely used to help reduce heartbeat, prevent arrhythmias and reduce the need for oxygen in the myocardium.
The use of disopyramide ( ritmodan ) is recommended.
In case of detected rhythm disturbances (atrial fibrillation), amiodarone or sotalol is used . In this case, the prevention of thrombus formation in the left atrium is necessary, for which anticoagulants ( warfarin ) are administered.
There is also a surgical treatment for hypertrophic cardiomyopathy :
- excision of the interventricular septum at its base;
- cauterization of the hypertrophied septum base with 96% alcohol using a catheter;
- In recent years, the use of a pacemaker for dual-chamber constant pacing has been recommended.
Restrictive cardiomyopathy is a disease of the myocardium characterized by a violation of the contractile function of the heart muscle, reduced relaxation of its walls. Myocardium becomes rigid, the walls do not stretch, suffers filling with blood of the left ventricle. The thickening of the walls of the ventricle or its expansion is not observed, in contrast to the atria, experiencing increased stress.
Restrictive cardiomyopathy is the rarest form, it exists both as a standalone version and as a result of damage to the heart with a sufficiently large range of diseases that should be excluded in the course of specifying the diagnosis.
These are amyloidosis, hemochromatosis, sarcoidosis, endomyocardial fibrosis, Löffler’s disease, fibroelastosis, and sometimes lesions of the cardiac conduction system (Fabry disease), systemic scleroderma, and others. In children, there are lesions of the heart due to glycogen metabolism disorders.
The insidiousness of this disease lies in the fact that complaints for a patient for the first time arise only at the stage of development of heart failure relating to the terminal part of the disease. Usually, the cause of the circulation is the appearance of peripheral edema, an increase in the size of the abdomen (ascites is a liquid in the abdominal cavity), and swelling of the jugular veins in the neck. A little later, shortness of breath joins the clinic.
On the radiograph, the heart has the usual dimensions, but an increase in the atria and signs of blood stagnation in the pulmonary circulation are detected.
ECG changes are not specific.
Ultrasound of the heart (echocardiography) provides valuable information:
- measurement of myocardial thickness (marked thickening of the walls is observed in amyloidosis and their slightly less change in other diseases),
- increase in the size of the left atrium, assessment of the pericardium (differential diagnosis with pericardial diseases that can give the same symptoms; the presence of calcifications in the pericardium excludes the diagnosis of restrictive cardiomyopathy ).
Laboratory diagnosis of restrictive cardiomyopathy has no specific signs, but is important for identifying secondary causes of heart damage.
Treatment of restrictive cardiomyopathy
Treatment is a difficult task due to late patient appeal, difficulty in diagnosing, and the lack of reliable methods for stopping the process. Heart transplantation may be ineffective due to the recurrence of the process in the transplanted heart.
With the established secondary character of the lesion, there are specific methods of action, for example, bloodletting in hemochromatosis , corticosteroids in sarcoidosis.
The rest of the treatment is symptomatic, aimed at eliminating the clinic of heart failure. In case of cardiac arrhythmias, antiarrhythmic drugs are prescribed. Anticoagulants are used to prevent thromboembolic complications.
Patients with restrictive cardiomyopathy are disabled. The prognosis of the disease is unfavorable, mortality for 2 years reaches 50%.