Classification of Cardiomyopathies and Indication for Endomyocardial Biopsy Revisited

Abstract

The first classifications of cardiomyopathies from 1980 and 1996 described them as heart muscle diseases, with dilated (DCM), hypertrophic (HCM), restrictive (RCM), arrhythmogenic right ventricular (ARVC), and nonclassifiable cardiomyopathies. Furthermore, the World Health Organization/International Society and Federation of Cardiology (WHO/ISFC) classification from 1996 listed among the specific cardiomyopathies inflammatory cardiomyopathy as a new and distinct entity, which was defined histologically as myocarditis in association with cardiac dysfunction. Infectious and autoimmune forms of inflammatory cardiomyopathy were recognized. Viral cardiomyopathy was defined as viral persistence in a dilated heart without ongoing inflammation. If it was accompanied by myocardial inflammation, it was termed inflammatory viral cardiomyopathy (or viral myocarditis with cardiomegaly). This entity was further elucidated in a World Heart Federation consensus meeting in 1999 by quantitative immunohistological criteria (< 14 infiltrating cells/mm(2)) and the etiology by molecular biological methods, e.g., polymerase chain reaction, as viral, bacterial, or autoimmune (= nonmicrobial). The development of molecular genetics, with the discovery of a genetic background in several forms of cardiomyopathies previously alluded to as "of unknown origin", was the origin of a debate on a new classification based on genomics. A genomic/postgenomic classification was postulated taking the underlying gene mutations and the cellular level of expression of encoded proteins into account, thus distinguishing cytoskeleton (cytoskeletalopathies, e.g., DCM or ARVC), sarcomeric (sarcomyopathies as in HCM and RCM) and ion channel (channelopathies, e.g., long or short QT syndrome and Brugada's syndrome) cardiomyopathies. Such a classification of cardiomyopathies was proposed in 2006 by the American Heart Association (AHA), which took the rapid evolution of molecular genetics in cardiology into account. It also introduced several recently described diseases, and is unique in that it incorporated ion channelopathies even without hemodynamic dysfunction as a "primary" cardiomyopathy. The ESC (European Society of Cardiology) Working Group on Myocardial and Pericardial Diseases has deliberately taken a different approach based on a clinically oriented classification in which heart muscle disorders were grouped according to morphology and function. This obviously remains the clinically most useful approach for the diagnosis and management of patients and families with heart muscle disease. In the ESC position statement published in 2008, cardiomyopathies were defined as myocardial disorders in which the heart muscle is structurally and functionally abnormal, and in which coronary artery disease, hypertension, valvular and congenital heart disease are absent or do not sufficiently explain the observed myocardial abnormality. The aim was to help clinicians look beyond generic diagnostic labels in order to reach more specific diagnoses. In parallel, a scientif...

The structural basis of alpha-tropomyosin linked (Asp230Asn) familial dilated cardiomyopathy

“…Hematoxylin and eosin staining of hearts from D230N-high mice at 6 months of age were negative for inflammatory infiltration (Figure 3A–C) [35, 36]. The only histologic abnormality in these hearts were broadened intercalated discs, a common, non-specific, finding in DCM [37].…”

Association between ACR1 gene product expression and cardiomyopathy in children

“…The European Society of Cardiology has defined cardiomyopathy in children as ‘a heart disease generated by an abnormal cardiac structure and function caused by non-coronary heart disease, hypertension, valvular heart disease or congenital heart disease’ (1,2). Statistics show the morbidity of pediatric cardiomyopathy has been on the increase annually probably due to the increasing number of immunocompromised infants and the aggravation of environmental pollution and other environmental problems (3). Relevant research results show that the current incidence of cardiomyopathy in children is ~0.001% (4) while postoperative rehabilitation is extremely poor for children with cardiomyopathy (5), the mortality rate after surgical procedures is approximately 30% and there is a high need for cardiac transplantation (6).…”

Leitlinien – Lehrbuchersatz, Handlungsanweisung für den Alltag oder Fessel?

“…Dieser Wertung schließen sich Pankuweit et al in ihrem Beitrag zu Kardiomyopathien und Myokarditis im Spiegel neuer Klassifikationen [7] ebenso an wie der Vorstellung, dass die neuen Empfehlungen der AHA zur Endomyokardbiopsie zwar ein, aber eben nur ein, allerdings richtiger und wichtiger Schritt in eine zukunftsfähige Richtung sind. Die Working Group Myocardial und Pericardial Diseases der ESC orientiert sich zu Recht am klinischen Phänotyp der Kardiomyopathien und erst in zweiter Linie an einem in der klinischen Ausprägung recht variablen Genotyp.…”