The Netherlands Arrhythmogenic Cardiomyopathy Registry: design and status update

Background Clinical research on arrhythmogenic cardiomyopathy (ACM) is typically limited by small patient numbers, retrospective study designs, and inconsistent definitions. Aim To create a large national ACM patient cohort with a vast amount of uniformly collected high-quality data that is readily available for future research. Methods This is a multicentre, longitudinal, observational cohort study that includes (1) patients with a definite ACM diagnosis, (2) at-risk relatives of ACM patients, and (3) ACM-associated mutation carriers. At baseline and every follow-up visit, a medical history as well information regarding (non-)invasive tests is collected (e. g. electrocardiograms, Holter recordings, imaging and electrophysiological studies, pathology reports, etc.). Outcome data include (non-)sustained ventricular and atrial arrhythmias, heart failure, and (cardiac) death. Data are collected on a research electronic data capture (REDCap) platform in which every participating centre has its own restricted data access group, thus empowering local studies while facilitating data sharing. Discussion The Netherlands ACM Registry is a national observational cohort study of ACM patients and relatives. Prospective and retrospective data are obtained at multiple time points, enabling both cross-sectional and longitudinal research in a hypothesis-generating approach that extends beyond one specific research question. In so doing, this registry aims to (1) increase the scientific knowledge base on disease mechanisms, genetics, and novel diagnostic and treatment strategies of ACM; and (2) provide education for physicians and patients concerning ACM, e. g. through our website (www.acmregistry.nl) and patient conferences

Diagnosis of arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D); Proposed Modification of the Task Force Criteria

BACKGROUND: In 1994, an International Task Force proposed criteria for the clinical diagnosis of arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) that facilitated recognition and interpretation of the frequently nonspecific clinical features of ARVC/D. This enabled confirmatory clinical diagnosis in index cases through exclusion of phenocopies and provided a standard on which clinical research and genetic studies could be based. Structural, histological, electrocardiographic, arrhythmic, and familial features of the disease were incorporated into the criteria, subdivided into major and minor categories according to the specificity of their association with ARVC/D. At that time, clinical experience with ARVC/D was dominated by symptomatic index cases and sudden cardiac death victims-the overt or severe end of the disease spectrum. Consequently, the 1994 criteria were highly specific but lacked sensitivity for early and familial disease. METHODS AND RESULTS: Revision of the diagnostic criteria provides guidance on the role of emerging diagnostic modalities and advances in the genetics of ARVC/D. The criteria have been modified to incorporate new knowledge and technology to improve diagnostic sensitivity, but with the important requisite of maintaining diagnostic specificity. The approach of classifying structural, histological, electrocardiographic, arrhythmic, and genetic features of the disease as major and minor criteria has been maintained. In this modification of the Task Force criteria, quantitative criteria are proposed and abnormalities are defined on the basis of comparison with normal subject data. CONCLUSIONS: The present modifications of the Task Force Criteria represent a working framework to improve the diagnosis and management of this conditio

Geographical distribution of plakophilin-2 mutation prevalence in patients with arrhythmogenic cardiomyopathy

Arrhythmogenic cardiomyopathy (AC) is characterised by myocardial fibrofatty tissue infiltration and presents with palpitations, ventricular arrhythmias, syncope and sudden cardiac death. AC is associated with mutations in genes encoding the desmosomal proteins plakophilin-2 (PKP2), desmoplakin (DSP), desmoglein-2 (DSG2), desmocollin-2 (DSC2) and junctional plakoglobin (JUP). In the present study we compared 28 studies (2004–2011) on the prevalence of mutations in desmosomal protein encoding genes in relation to geographic distribution of the study population. In most populations, mutations in PKP2 showed the highest prevalence. Mutation prevalence in DSP, DSG2 and DSC2 varied among the different geographic regions. Mutations in JUP were rarely found, except in Denmark and the Greece/Cyprus region