Restrictive cardiomyopathy (RCM) is characterized by ventricular walls without compliance, which resist the diastolic filling; usually the left ventricle, or both ventricles may be affected. The symptoms are fatigue and dyspnea on exertion. The diagnosis is made by echocardiography and cardiac catheterization. The treatment is often unsatisfactory and is best directed at the cause. Surgical procedures are sometimes useful.

RCM is the form of cardiomyopathy with the lowest prevalence. It is classified as

Restrictive cardiomyopathy (RCM) is characterized by ventricular walls without compliance, which resist the diastolic filling; usually the left ventricle, or both ventricles may be affected. The symptoms are fatigue and dyspnea on exertion. The diagnosis is made by echocardiography and cardiac catheterization. The treatment is often unsatisfactory and is best directed at the cause. Surgical procedures are sometimes useful. RCM is the form of cardiomyopathy with the lowest prevalence. It is classified as Nichtobliterierend (Myokardinfiltration by an abnormal substance) obliterative (fibrosis of the endocardium and subendocardium) Each of the two forms can diffuse or not diffuse (when the disease affects only a nonuniform ventricle or a portion of a ventricle). Etiology The cause is usually unknown; known reasons are listed in causes of restrictive cardiomyopathy. Some diseases that cause RCM also affect other tissues (eg. As amyloidosis, Hämachromatose). Some infiltrative cardiomyopathies also affect other cardiac tissue. Rarely amyloidosis affects the coronary arteries. Sarcoidosis and Fabry’s disease may also affect the nodal conduction tissue. The Loeffler’s syndrome (a subclass of the hypereosinophilic syndrome with primary cardiac involvement), which occurs in the tropics, begins as acute arteritis with eosinophilia, followed by thrombus formation on the endocardium, chordae and the AV valve and proceeds to fibrosis. An endocardial fibroelastosis that occurs in temperate zones, only affects the left ventricle. Causes the restrictive cardiomyopathy cause Examples Genetic abnormalities Fabry disease Gaucher’s disease Connective Tissue hemochromatosis amyloidosis diffuse systemic sclerosis Endocardial fibroelastosis Other carcinoid tumors hypereosinophilic syndrome (including Löffler’s syndrome) radiation sarcoidosis Pathophysiology endocardial thickening or myocardial infiltration (sometimes death of myocytes, Papillarmuskelinfiltration, compensatory myocardial hypertrophy and fibrosis) may occur in one, typically the left, or both ventricles. As a result, it can lead to paint functions of the mitral or tricuspid valve, which leads to failure. By myocardial infiltration or the endocardial thickening a functional AV valve insufficiency may result. If nodal and conduction tissue is affected, sinoatrial paint functions can occur that cause sometimes varying degrees of AV block. The main consequence for the hemodynamics is a diastolic dysfunction (diastolic dysfunction) with a rigid ventricle without compliance, with a limited diastolic filling and a high filling pressure, which leads to pulmonary venous congestion. Systolic function may deteriorate if compensatory hypertrophy of infiltrated and fibrotic ventricles is inadequate. Wall Permanent blood clots can form and lead to systemic embolism. Symptoms and signs The symptoms include exertional dyspnea, orthopnea and one when the RV is affected, peripheral edema. The fatigue caused by a fixed cardiac output because of resistance to ventricular filling. Atrial and ventricular arrhythmias and AV block are common; Angina and syncope are rare. The symptoms and findings are similar to those at a constrictive pericarditis (pericarditis: Constrictive pericarditis). The physical examination shows a quiet precordium, a flat and fast carotid, pulmonary rales and a pronounced damming the jugular veins with a fast y-waste (Normal jugular vein waves.). A fourth heart sound (S4) is almost always present, a third heart sound (S3) can occur and must be distinguished from a precordial knock of constrictive pericarditis. In some cases, produces a noise of functional mitral or tricuspid regurgitation, as the myocardial or endocardial infiltration or fibrosis change the chordae and ventricular geometry. A paradoxical pulse does not occur. Diagnostic echocardiography MRT root cause analysis are needed, an ECG, chest x-ray and an echocardiogram. The ECG is usually changed nonspecific, showing ST-segment and T-wave changes, and sometimes a low voltage. Sometimes pathological Q waves occur that are not caused by a previous myocardial infarction. A LV hypertrophy due to compensatory myocardial hypertrophy occurs sometimes. In the chest X-ray recording, the heart size is often normal or small but can be enlarged also in the final stages of amyloidosis or hemochromatosis. Echocardiography shows normal systolic function. Common findings include dilated atria and myocardial hypertrophy. RCM due to amyloidosis shows an unusual bright echo pattern of the myocardium. The echocardiography helps to identify a constrictive pericarditis with its thickened myocardium, but a paradoxical septal may occur with any of the diseases. If the diagnosis is still in doubt, the CT may be more sensitive to show whether the pericardium is normal; MRI can exhibit altered Myokardtextur in diseases with myocardial infiltration (z. B. Amyloid or iron). Cardiac catheterization and myocardial biopsy are often not necessary. If carried out, it can be seen in the cardiac catheterization at a RCM high atrial pressures with a prominent y-waste and an early diastolic “dip”, followed by a plateau in the diastolic Ventrikeldruckkurve. In contrast to the findings in constrictive pericarditis a diastolic pressure in LV is here usually several mmHg higher than in the RV. The angiography shows normal-sized Ventrikelhöhlen with normal or reduced systolic shortening. An AV valve insufficiency may be present. A biopsy can show an endocardial fibrosis and thickening, myocardial infiltration with iron or amyloid and chronic myocardial fibrosis. Coronary angiography is normal, except when amyloidosis affects epicardial coronary arteries. Occasionally, cardiac catheterization does not lead to diagnosis, rarely a thoracotomy is required to investigate the pericardium. It should studies which demonstrate the most common causes of RCM (eg., Rectal biopsy for amyloidosis, iron tests or liver biopsies at a hemochromatosis), are performed. Prognosis The prognosis is poor (see Fig. Diagnosis and treatment of cardiomyopathies), because the diagnosis is often made at a late stage. In most patients, there is no treatment available; symptomatic and supportive assistance can be provided. Treatment Cause treated diuretics contemplated may septal myectomy, pacemaker implantation, implantable cardioverter defibrillator diuretics can be used in patients with (lung) edema, but with caution, as they reduce the preload; However, a ventricle without compliance depends on the preload to maintain cardiac output. Digoxin can hemodynamic changes affecting little and can trigger serious arrhythmias in cardiomyopathy due to amyloidosis, as an extreme Digitalisempfindlichkeit is common here. If the heart rate is increased, ?-blockers or heart rate lowering calcium antagonist can be carefully used in low doses. Nachlastsenker (eg., Nitrates) may cause severe hypotension and are usually not helpful. The septal myectomy / ablation can alleviate some symptoms. A pacemaker implantation can help older patients who wish to avoid more invasive procedures. Implantable cardioverter defibrillators can help with an increased risk of sudden cardiac death younger patients. If the diagnosis is made at an early stage, a specific therapy of hemochromatosis, sarcoidosis or Loeffler’s syndrome can help. A transplant is not recommended because the disease in transplanted heart may recur. Important points at the restrictive cardiomyopathy performs endocardial thickening or myocardial infiltration into a rigid, unyielding ventricle and thus to a diastolic dysfunction; the systolic function is normal until the later course of the disease. Sometimes the heart valve tissue or the pipe system is affected, causing valvular insufficiency or heart block and arrhythmias. The etiology is not usually known, but some cases are caused by amyloidosis hemochromatosis or sarcoidosis. The diagnosis is made by echocardiography and testing for the causes. Treatment is often unsatisfactory when the cause can not be addressed; Diuretics can help with edema or pulmonary vascular congestion patient but must be used with caution in order to avoid a reduction in preload. Implantable devices can extend the life of certain patients.

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