Cardiomyopathy

Symptoms

Dilated cardiomyopathy (DCM) is characterized by a significant expansion of all cavities of the heart, hypertrophy and a decrease in myocardial contractility. Signs of dilated cardiomyopathy manifest themselves already at a young age - at 30-35 years. In the etiology of DCM, infectious and toxic effects, metabolic, hormonal, and autoimmune disorders presumably play a role; in 10-20% of cases, cardiomyopathy is familial.

The severity of hemodynamic disorders in dilated cardiomyopathy is due to the degree of decrease in contractility and pumping function of the myocardium. This causes an increase in pressure first in the left and then in the right cavities of the heart. Clinically, dilated cardiomyopathy is manifested by signs of left ventricular failure ( shortness of breath , cyanosis, attacks of cardiac asthma and pulmonary edema), right ventricular failure (acrocyanosis, pain and enlargement of the liver, ascites , edema, swelling of the neck veins), heart pain, non-stopping nitroglycerin, palpitations.

Causes

The etiology of primary cardiomyopathies has not been fully understood to date. Possible causes of cardiomyopathy include:

•    Viral infections caused by coxsackieviruses , herpes simplex , influenza , etc.;
•    Hereditary predisposition (genetically inherited defect that causes improper formation and functioning of muscle fibers in hypertrophic cardiomyopathy);
•    Transferred myocarditis;
•    Damage to cardiomyocytes by toxins and allergens;
•    Violations of endocrine regulation (detrimental effect on cardiomyocytes of somatotropic hormone and catecholamines);
•    Immune dysregulation.

Treatment

There is no specific therapy for cardiomyopathies, therefore, all therapeutic measures are aimed at preventing complications incompatible with life. Treatment of cardiomyopathies in the stable phase is outpatient, with the participation of a cardiologist ; periodic planned hospitalization in the cardiology department is indicated for patients with severe heart failure, emergency - in cases of development of intractable paroxysms of tachycardia, ventricular premature beats, atrial fibrillation, thromboembolism, pulmonary edema.

Patients with cardiomyopathy need lifestyle changes:

•    Decreased physical activity
•    Following a diet with limited intake of animal fats and salt
•    Exclusion of harmful environmental factors and habits.
•    These activities significantly reduce the load on the heart muscle and slow down the progression of heart failure.
•    In cardiomyopathies, it is advisable to prescribe drug therapy:
•    Diuretics to reduce pulmonary and systemic venous congestion
•    Cardiac glycosides in violation of contractility and pumping function of the myocardium
•    Antiarrhythmic drugs for heart rhythm correction
•    Anticoagulants and antiplatelet agents to prevent thromboembolic complications.
•    In exceptionally severe cases, surgical treatment of cardiomyopathies is performed: septal myotomy (resection of a hypertrophied section of the interventricular septum) with mitral valve replacement or heart transplantation.
 

Tests Required for Diagnosis

Objectively marked deformation of the chest (heart hump); cardiomegaly with border expansion to the left, right and up; deafness of heart tones at the apex, systolic murmur (with relative insufficiency of the mitral or tricuspid valve), gallop rhythm are heard. With dilated cardiomyopathy, hypotension and severe forms of arrhythmias ( paroxysmal tachycardia , extrasystole, atrial fibrillation , blockades) are detected.
An electrocardiographic study revealed hypertrophy predominantly of the left ventricle, disturbances in cardiac conduction and rhythm. Echocardiography shows diffuse myocardial damage, sharp dilatation of the heart cavities and its predominance over hypertrophy, intact heart valves, and diastolic dysfunction of the left ventricle. X-ray with dilated cardiomyopathy is determined by the expansion of the boundaries of the heart.

Useful info

Characteristic

Restrictive cardiomyopathy (RCMP) is a rare myocardial lesion that usually occurs with endocardial involvement (fibrosis), inadequate diastolic relaxation of the ventricles and impaired cardiac hemodynamics with preserved myocardial contractility and the absence of its pronounced hypertrophy.
In the development of RCMP, a large role is played by severe eosinophilia, which has a toxic effect on cardiomyocytes. With restrictive cardiomyopathy, thickening of the endocardium and infiltrative, necrotic, fibrous changes in the myocardium occur. The development of the RCMP goes through 3 stages:

•    Stage I - necrotic - characterized by severe eosinophilic infiltration of the myocardium and the development of coronaritis and myocarditis ;

•    Stage II - thrombotic - manifested by endocardial hypertrophy, parietal fibrin deposits in the heart cavities, vascular myocardial thrombosis;

•    Stage III - fibrotic - is characterized by widespread intramural myocardial fibrosis and nonspecific obliterating endarteritis of the coronary arteries.

Symptoms

Restrictive cardiomyopathy can occur in two types: obliterating (with fibrosis and obliteration of the ventricular cavity) and diffuse (without obliteration). With restrictive cardiomyopathy, there are phenomena of severe, rapidly progressive congestive circulatory failure: severe shortness of breath, weakness with little physical effort, increasing edema, ascites, hepatomegaly , swelling of the neck veins.

Diagnostics

In size, the heart is usually not enlarged, with auscultation, a gallop rhythm is heard. On the ECG, atrial fibrillation, ventricular arrhythmias are recorded, a decrease in the ST-segment with T-wave inversion can be determined. Radiological phenomena of venous congestion in the lungs, slightly enlarged or unchanged heart sizes are noted. The echoscopic picture reflects insufficiency of the tricuspid and mitral valves, a decrease in the size of the obliterated cavity of the ventricle, a violation of the pumping and diastolic function of the heart. Eosinophilia is noted in the blood.

Arrhythmogenic right ventricular cardiomyopathy:

Characteristic

The development of arrhythmogenic right ventricular cardiomyopathy (ARVC) characterizes the progressive replacement of right ventricular cardiomyocytes with fibrous or adipose tissue, accompanied by various ventricular arrhythmias, including ventricular fibrillation . The disease is rare and little studied; heredity, apoptosis, viral and chemical agents are called as possible etiological factors.

Symptoms

Arrhythmogenic cardiomyopathy can develop as early as adolescence or adolescence and is manifested by palpitations, paroxysmal tachycardia, dizziness, or fainting. In the future, the development of life-threatening types of arrhythmias is dangerous: ventricular extrasystole or tachycardia , episodes of ventricular fibrillation, atrial tachyarrhythmias, atrial fibrillation or flutter .

Diagnostics

In arrhythmogenic cardiomyopathy, the morphometric parameters of the heart are not changed. Echocardiography shows moderate right ventricular enlargement, dyskinesia, and local protrusion of the apex or inferior wall of the heart. MRI reveals structural changes in the myocardium: local thinning of the myocardial wall, aneurysms.

Complications:

With all types of cardiomyopathies, heart failure progresses, arterial and pulmonary thromboembolism , cardiac conduction disorders, severe arrhythmias (atrial fibrillation, ventricular extrasystole, paroxysmal tachycardia), sudden cardiac death syndrome may develop .

Diagnostics:

When diagnosing cardiomyopathy, the clinical picture of the disease and the data of additional instrumental methods are taken into account. The ECG usually shows signs of myocardial hypertrophy, various forms of rhythm and conduction disturbances, and changes in the ST segment of the ventricular complex. X -ray of the lungs can reveal dilatation, myocardial hypertrophy, congestion in the lungs.

EchoCG data are especially informative in cardiomyopathies, which determine myocardial dysfunction and hypertrophy, its severity and the leading pathophysiological mechanism (diastolic or systolic insufficiency). According to indications, it is possible to conduct an invasive examination - ventriculography . Modern methods of visualization of all parts of the heart are MRI of the heart and MSCT . Probing of the heart cavities makes it possible to take cardiobiopsy specimens from the heart cavities for morphological examination.