The aim of this project is to investigate if cardiomyocytes can efficiently be collected during endocardial voltage mapping in patients with arrhythmogenic right ventricular cardiomyopathy/dysplasia. Thirty patients suffering from arrhythmogenic right ventricular cardiomyopathy/dysplasia cardiac and needing endocardial voltage mapping for disease diagnosis and/or prognosis assessment will be included. The main outcome will be the percentage of patients in whom mapping will allow to collect intact cardiomyocytes from which high quality DNA extraction will be achieved. Other outcomes include the identification of new mutational mechanisms as somatic mosaicism in selected genes (PKP2, DSCG2 DSP) and the feasibility of epigenetic analysis of these genes.