INTRODUCTION

Dilatation of the right ventricular outflow tract (RVOT), in association with regional right ventricular (RV) akinesia, dyskinesia, or aneurysm, is one of the major criteria in the diagnosis of arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) [1]. It is defined by measuring the diameter of the RVOT by two-dimensional (2D) transthoracic echocardiography (TTE) at end diastole in the parasternal short-axis (PSAX) and the parasternal long-axis (PLAX) views.
Cardiovascular magnetic resonance imaging (CMR) could also be used to measure the end-diastolic diameter of the RVOT, in views that are similar to the 2D TTE views, which could be helpful in diagnosing RVOT dilatation in patients with poor echocardiographic windows. However, the reference ranges ​​for the RVOT diameter by CMR have not been reported, and the correlation and agreement between CMR and TTE measurements has not been studied in children.
We therefore aimed to provide reference ranges for the RVOT diameter in the strict transverse and sagittal views by CMR in children and adolescents with normal RVOT anatomy, and to compare the measurements with those obtained by 2D TTE according to the recommendations in the 2010 revised Task Force Criteria (TFC) of ARVC/D.[1]