Reply: The MOGE(S) classification for a phenotype-genotype nomenclature of cardiomyopathy: more questions than answers?

Dr. Pasotti, as most other cardiologists with expertise in cardiomyopathies do 1, so aptly perceives the need for a more comprehensive classification that describes the phenotype and the related “red flag” involvement of other organs, and genetic (or nongenetic) basis of the disease and supports the attempt of the nosology proposed by MOGE(S) (morphofunctional characteristics [M], organ involvement [O], genetic or familial inheritance pattern [G], and an explicit etiological annotation [E], with details of genetic defects or underlying disease cause [S]) (2). As commented by Elliott 3 on the application of MOGE(S) 2, arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVC/D) matches the complexity of a disease in which the diagnostic criteria have been debated and modified. In the original definition, the ARVC/D was typically a right ventricular cardiomyopathy 4. The recently modified Task Force Criteria recognizes ARVC/D as classic right (the most common), biventricular, or predominantly left types 5. The diagnosis relies on the demonstration of structural, functional, and electrophysiological abnormalities that are caused by or reflect the underlying histological changes. In both the original and revised criteria, imaging-based morphological and functional data (i.e., right ventricular size, akinesia, dyskinesia, or aneurysm, dyssynchronous right ventricular contraction) remain the major diagnostic contributors. In the routine clinical practice, the echocardiographic or cardiac magnetic resonance (CMR) information are, along with electrocardiographic features, the major alerting traits. In the revised criteria, definite diagnosis is entertained when 2 major (M), or 1 major and 2 minor (m) criteria, or 4 minor criteria from different categories are present, and the diagnosis of the borderline ARVC/D is made when 1 major and 1 minor, or 3 minor criteria from different categories are present. A diagnosis of possible ARVC/D is made if 1 major or 2 minor criteria from different categories are observed. The application of these criteria could be relatively simple in MOGE(S) (2). We emphatically insisted in our presentation 3 that the proposed classification is flexible and allows easy modification to the MOGES app. In the case of ARVC/D, we may use M for major and m for minor; the minor criteria can be further specified as m3×3 (3 minor criteria from 3 categories) or m3×2 (3 minor criteria from 2 categories).