cardiovascular disorders
Restrictive Cardiomyopathy
Introduction
Restrictive cardiomyopathy is characterized by noncompliant ventricular walls that resist diastolic filling; one (most commonly the left) or both ventricles may be affected. Symptoms include fatigue and exertional dyspnea. Diagnosis is by echocardiography and cardiac catheterization. Treatment is often unsatisfactory and is best directed at the cause. Surgery is sometimes useful. A cardiomyopathy is a primary disorder of the heart muscle (see also Overview of Cardiomyopathies ). Restrictive cardiomyopathy is the least prevalent form of cardiomyopathy. Restrictive cardiomyopathy can affect one or both ventricles. Either type may be diffuse or nondiffuse (when the disorder affects only one ventricle or part of one ventricle unevenly). Restrictive cardiomyopathies can be classified into 4 etiologic categories: Infiltrative (eg, amyloidosis, sarcoidosis) Non-infiltrative (eg, idiopathic, systemic sclerosis) Storage diseases (eg, Fabry disease, hemochromatosis) Endomyocardial disorders (eg, endomyocardial fibrosis, hypereosinophilic syndrome, carcinoid syndrome, metastatic cancer, drugs [hydroxychloroquine,ergotamine, methysergide]) Primary restrictive cardiomyopathies include idiopathic restrictive cardiomyopathy and endomyocardial fibrosis while the others are considered secondary forms. Some of these are inherited, and others are acquired ( General reference ). In patients with hypereosinophilic syndrome and extensive endocardial fibrosis, thrombus can form in the apices and inflow tracts ventricles compromising the size of the ventricular cavities. This type of restrictive cardiomyopathy is termed obliterative. 