Dilated Cardiomyopathies as a Cause of Congestive Heart Failure

DEFINITION AND CLASSIFICATION: Cardiomyopathies are disorders affecting the heart muscle that frequently result in congestive heart failure. Five major forms are recognized: dilated, hypertrophic, restrictive, right ventricular, and nonclassifiable cardiomyopathies with distinct hemodynamic properties. Furthermore, the new WHO/WHF definition also comprises inflammatory cardiomyopathy, defined as myocarditis in association with cardiac dysfunction. Idiopathic, autoimmune, and infectious forms of inflammatory cardiomyopathy were recognized. Viral cardiomyopathy is defined as viral persistence in a dilated heart. It may be accompanied by myocardial inflammation and then termed inflammatory viral cardiomyopathy (or viral myocarditis with cardiomegaly). If no inflammation is observed in the biopsy of a dilated heart (< 14 lymphocytes and macrophages/mm2), the term viral cardiomyopathy or viral persistence in dilated cardiomyopathy should be applied. DIAGNOSIS AND TREATMENT: In recent years, there have been breakthroughs in understanding the molecular and genetic mechanisms involved in this group of conditions, enabling improvement of diagnostic strategies and introduction of new therapies. Ongoing evaluation of antiviral, immunoglobulin, and immunosuppressive therapies including the European Study of Epidemiology and Treatment of Cardiac Inflammatory Diseases (ESETCID), removal of antibodies by immunoadsorption, anticytokine and gene therapy, as well as the mechanical support devices may provide new treatment options.