Arrhythmic Risk in Paediatric Patients Undergoing Surgical Repair for Pulmonary Atresia with Intact Ventricular Septum Pietro Paolo Tamborrino 1,2 , Corrado Di Mambro 1,2,* , Cecilia Marcolin 1,2 , Walter Vignaroli 3 , Giulia Cafiero 4 , Gianluca Brancaccio 3 , Sonia Albanese 3 , Massimo Stefano Silvetti 1,2 , Adriano Carotti 3 and Fabrizio Drago 1,2 1 Paediatric Cardiology and Cardiac Arrhythmia Unit, Department of Paediatric Cardiology and Cardiac Surgery, Bambino Gesù Children’ s Hospital, IRCCS, Rome, Italy 2 European Reference Network for Rare and Low Prevalence Complex Disease of the Heart 3 Paediatric Cardiac Surgery Unit, Department of Paediatric Cardiology and Cardiac Surgery, Bambino Gesù Children’ s Hospital, IRCCS, Rome, Italy 4 Sport Medicine Unit, Department of Paediatric Cardiology and Cardiac Surgery, Bambino Gesù Children’ s Hospital, IRCCS, Rome, Italy * Corresponding Author: Corrado Di Mambro. Email: corrado.dimambro@opbg.net Received: 24 July 2020 Accepted: 10 November 2020 ABSTRACT Introduction: While previous studies only focused on the arrhythmic risk associated with specific correction stra- tegies, this study evaluates this risk in a large cohort of paediatric patients with all phenotypes of PA-IVS after surgical repair. Methods: In this single centre observational cohort study, we retrospectively evaluated 165 patients with a diagnosis of PA-IVS and we excluded those with an exclusively percutaneous treatment, patients lost or with insufficient follow-up and those affected by other arrhythmic syndromes. Surgical history and clinical out- comes were reviewed. Results: 86 patients were included in the study (54 male [62.8%], mean age 16.4 ± 6.1 years), with median follow-up from definitive repair of 12.8 years (6.4–18.9 years). They underwent three different final repairs: 23 patients (26.7%) univentricular palliation, 43 (50%) biventricular correction, and 20 (23.3%) one and a half ventricle correction. Thirteen patients (15%) developed arrhythmia: 6 patients (all the subgroups) sinus node disfunction (SND); 2 (biventricular repair) premature ventricular complexes; 2 (one and a half ventricle repair) non-sustained ventricular tachycardia; 1 (biventricular repair) intra-atrial re-entrant tachycardia; 1 (one and a half ventricle repair) supraventricular tachyarrhythmia; 1 (biventricular repair) atrial fibrillation. Three patients with SND needed a pacemaker implantation. Only Fontan circulation showed an association with SND, while the other two groups heterogeneous types of arrhythmias. Conclusions: The low arrhythmic risk is related to sur- gical repair, it does not appear to be associated with native cardiomyopathy, and it appears to increase with length of follow up. Continuous follow-up in specialized centres is necessary to make an early diagnosis and to manage the potential haemodynamic impact at medium-long term. KEYWORDS Pulmonary atresia with intact ventricular septum; arrhythmic risk; univentricular palliation; Fontan circulation; biventricular repair; one and a half repair This work is licensed under a Creative Commons Attribution 4.0 International License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. DOI: 10.32604/CHD.2021.013038 ARTICLE ech T Press Science