AEPC YIA Session（II-AEPCYIA）

[II-AEPCYIA-1] Atenolol should not be the ß-blocker of choice for symptomatic children with catecholaminergic polymorphic ventricular tachycardia

^○Puck J. Peltenburg¹, Krystien V.V. Lieve g¹, Christian van der Werf g¹, Isabelle Denjoy g², Guillermo Perez g³, Carmen Perez³, Ferran Roses i Noguer⁴, Johan M. Bos⁵, Connor Lane⁵, Vibeke M.Almaas⁶, Aurora Djubsjöbacka⁷, Sing C. Yap⁸, Yuko Wada⁹, Thomas Roston¹⁰, Veronica Dusi¹¹, Takeshi Aiba¹², Maarten van den Berg¹³, Thomas Robyns¹⁴, Jason Roberts¹⁵, Esther Zorio¹⁶, Udi Chorin¹⁷, Sally-Ann B. Clur¹, Nico A. Blom^1,18, Martin Borggrefe¹⁹, Andrew M.Davis²⁰, Jon Skinner²¹, Elijah Behr²², Christopher Semsarian²³, Prince J. Kannankeril²⁴, Jacob Tfelt-Hansen²⁵, Frederic Sacher²⁶, Wataru Shimizu¹², Peter J. Schwartz¹¹, Shu Sanatani¹⁰, Seiko Ohno⁹, Janneke Kammeraad⁸, Heikki Swan⁷, Kristina Haugaa⁶, Vincent Probst²⁷, Michael J. Ackerman⁵, Janice A. Till⁴, Ramon Brugada³, Arthur A.M. Wilde¹, Antoine Leenhardt², (1.AmsterdamUMC - location AMC, the Netherlands, 2.Hôpital Bichat, Paris, France, 3.Universitat de Girona-IDIBGI, Girona, Spain, 4.Royal Brompton Hospital, London, United Kingdom, 5.Mayo Clinic, Rochester, United States, 6.Oslo University Hospital, Oslo, Norway, 7.Helsinki University Hospital and Helsinki University, Helsinki, Finland, 8.Erasmus Medical Center, Rotterdam, the Netherlands, 9.Shiga University of Medical Science, Otsu, Japan, 10.University of British Columbia, Vancouver, Canada, 11.Istituto Auxologico Italiano, IRCCS, Center for Cardiac Arrhythmias of Genetic Origin, Milan,Italy, 12.National Cerebral and Cardiovascular Centre, Suita, Osaka, Japan, 13.University Medical Centre, Groningen, the Netherlands, 14.University Hospitals Leuven, Leuven, Belgium, 15.Western University, London, Canada, 16.Hospital La Fe, Valencia, Spain, 17.Tel Aviv Sourasky Medical Center, Tel Aviv, Israel, 18.Leiden University Medical Center, Leiden, the Netherlands, 19.University Medical Centre Mannheim, Mannheim, Germany, 20.The Royal Children's Hospital Melbourne, Melbourne, Australia, 21.Starship Children's Hospital, Auckland, New Zealand, 22.St. George's, University of London, London, United Kingdom, 23.Royal Prince Alfred Hospital, Sydney, Australia, 24.Vanderbilt University Medical Center, Nashville, United States, 25.Rigshospitalet, Copenhagen, Denmark, 26.Bordeaux University Hospital, Bordeaux, France, 27.CHU de Nantes, Nantes, France, )

Introduction
Children with catecholaminergic polymorphic ventricular tachycardia (CPVT) are at risk for malignant ventricular arrhythmias during exercise and emotions, which may lead to arrhythmic events such as sudden cardiac death (SCD). Symptomatic patients are at particular risk for the reoccurrence of arrhythmic events. Beta-blockers are the cornerstone of therapy in patients with CPVT. However, studies comparing the efficacy of different types of betablockers are scarce. We aimed to determine the efficacy of different types of beta-blockers in reducing the risk for recurrent arrhythmic events in a large cohort of symptomatic children with CPVT.
Methods
Data were derived from the International CPVT Registry, a large retrospective observational cohort study. We included symptomatic children aged <19 years who were carrier of a RYR2 variant and who were prescribed a beta-blocker. The primary endpoint was the occurrence of an arrhythmic event (AE), defined as SCD, aborted cardiac arrest, appropriate ICD discharge or syncope. Time-dependent Cox-regression analyses were used to compare the occurrence of AEs between different beta-blockers corrected for possible confounders with nadolol as reference group.
Results
We included 267 children treated with a beta-blocker. One hundred five (39.3%) children were first treated with nadolol, 64 (24.0%) with propranolol, 43 (16.1%) with atenolol, 26 (9.7%) with metoprolol and 21 (7.9%) bisoprolol. Age at initiation of beta-blocker differed between the groups, with the youngest mean age in propranolol and highest in bisoprolol and metoprolol (10±4 years in propranolol, 13±4 years in bisoprolol and nadolol, overall-p=0.023). Sex, the proportion of probands and the proportion of patients treated with flecainide, left cardiac sympathetic denervation and an ICD were equally distributed among all groups. In total 86 (32.2%) children had an AE. The AE-rate was significantly higher in patients treated with atenolol compared to nadolol (hazard ratio (HR) 2.15, 95% confidence interval (CI) 1.05-4.40, p=0.036, Table). There were no significant differences in the AE-rate in patients treated with bisoprolol (HR 2.08, 95% CI 0.92-4.71), metoprolol (HR 1.79, 95% CI 0.82-3.92), and propranolol (HR 1.55, 95% CI 0.84-2.86) compared with nadolol.
Conclusions
Atenolol is associated with a higher risk for a subsequent arrhythmic event in symptomatic children with CPVT compared to nadolol.