{'fraction_non_alphanumeric': 0.025217932752179328, 'fraction_numerical': 0.011830635118306352, 'mean_word_length': 6.0, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Challenge of Early Identification of Arrhythmogenic (Right Ventricular) Cardiomyopathy.

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inherited heart muscle disease, histologically characterized by progressive cardiomyocyte loss and fibrofatty substitution, predominantly in the right ventricle (RV), predisposing to ventricular arrhythmias, sudden death, and heart failure.1 The disease shows significant phenotypic and genetic heterogeneity. Recent evidences suggest that the disease is not only an isolated RV pathology but is characterized by a spectrum of biventricular abnormalities, with predominant right, left, or balanced biventricular involvements.2 Therefore, the more inclusive definition of arrhythmogenic cardiomyopathy (AC) is currently considered more appropriate.3 Despite being a genetic disease, ARVC/AC usually occurs in young adults and rarely in infancy and adolescence, with a progressive course. An early recognition of ARVC/ AC is crucial for patient management because severe ventricular arrhythmias and sudden death can be the first disease manifestation, sometimes in the absence of detectable structural heart abnormalities.4 The diagnostic difficulties, particularly in ARVC/AC early concealed phase, are well known and have stimulated several publications exploring the possible improvements using different diagnostic modalities.1,3,5,6 International expert task forces tried to overcome the absence of a diagnostic gold standard by proposing multimodality diagnostic algorithms, such as the 2010 modified task force diagnostic criteria (mTFC),7 that tried to categorize the probability of ARVC (definite, borderline, possible, or absent) according to the presence of several major and minor criteria. However, these mTFC have some limitations. In particular, mTFC recommendations refer to the classic RV disease, not considering the other possible manifestations, such as left dominant and biventricular involvement, which probably require different diagnostic algorithms.2,3,8,9 Furthermore, since 2010, new technologies and clinical data are available.3,5 Lastly, limited data are available regarding validity of diagnostic tools to detect the disease in children and adolescents. In the current issue of Circulation: Cardiovascular Imaging, Pieles et al10 published the results of a wide retrospective study on suspected young ARVC patients, classified in the 4 probability groups according to the mTFC. The aim of this study was to investigate the diagnostic value of the echocardiographic parameters in children and adolescents, exploring the potential diagnostic usefulness of additional features, not included in the mTFC. The authors interestingly reported that a careful measurement of RV apical diameter can be useful for the diagnosis. RV apex is in fact 1 of the 3 described classic locations of ARVC, in the so-called the triangle of dysplasia.11 A second important result confirms previous reports3,5,12 about the usefulness of quantitative deformation analysis of RV wall by speckle tracking echocardiography. For instance, this technique has been used to identify subtle © 2019 American Heart Association, Inc. Circulation: Cardiovascular Imaging