Paediatric/young versus adult patients with congenital long QT syndrome or catecholaminergic polymorphic ventricular tachycardia

Abstract

Introduction Congenital long QT syndrome (LQTS) and catecholaminergic ventricular tachycardia (CPVT) are less prevalent cardiac ion channelopathies than Brugada syndrome in Asia. The present study compared paediatric/young and adult patients with these conditions. Method This was a territory-wide retrospective cohort study of consecutive patients diagnosed with congenital LQTS and CPVT attending public hospitals in Hong Kong. The primary outcome was spontaneous ventricular tachycardia/ventricular fibrillation (VT/VF). Results A total of 142 congenital LQTS (mean onset age= 27±23 years old) and 16 CPVT (mean presentation age=11±4 years old) patients were included. For congenital LQTS, arrhythmias other than VT/VF (HR=4.67, 95% confidence interval = [1.53–14.3], p=0.007), initial VT/VF (HR=3.25 [1.29–8.16], p=0.012) and Schwartz score (HR=1.90 [1.11–3.26], p=0.020) were predictive of the primary outcome for the overall cohort, whilst arrhythmias other than VT/VF (HR=5.41 [1.36–21.4], p=0.016) and Schwartz score (HR=4.67 [1.48–14.7], p=0.009) were predictive for the adult subgroup (>25 years old; n=58). All CPVT patients presented before the age of 25 but no significant predictors of VT/VF were identified. A random survival forest model identified initial VT/VF, Schwartz score, initial QTc interval, family history of LQTS, initially asymptomatic, and arrhythmias other than VT/VF as the most important variables for risk prediction in LQTS, and initial VT/VF/sudden cardiac death, palpitations, QTc, initially symptomatic and heart rate in CPVT. Conclusion Clinical and ECG presentation vary between the pediatric/young and adult congenital LQTS population. All CPVT patients presented before the age of 25. Machine learning models achieved more accurate VT/VF prediction. Funding Acknowledgement Type of funding sources: None. Kaplan-Meier survival curve for LQTSKaplan-Meier survival curve for CPVT

Clinical Characteristics, Genetic Basis and Healthcare Resource Utilisation and Costs in Patients with Catecholaminergic Polymorphic Ventricular Tachycardia: A Retrospective Cohort Study

“…This study was part of a wider study on cardiac arrhythmias that was approved by The Joint Chinese University of Hong Kong-New Territories East Cluster Clinical Research Ethics Committee. The cohort included consecutive patients diagnosed with CPVT between January 1st, 1997 to December 31st, 2018 in public hospitals or clinics of Hong Kong Hospital Authority [ 25 ]. Our team has previously used this system for conducting disease-based epidemiological or clinical studies for both prevalent and rare conditions [ 26 ], including Brugada syndrome [ 27 ] and long QT syndrome [ 28 , 29 ].…”

Attendance-related healthcare resource utilisation and costs in patients with long QT syndrome in Hong Kong: A retrospective cohort study

“…The cohort included consecutive patients diagnosed with LQTS between January 1 st , 1997 to December 31 st , 2019 in public hospitals or clinics under the Hong Kong Hospital Authority. This system has been used previously by our team to investigate rare congenital arrhythmic syndromes 13-15 as well as common diseases 16-18 . The patient identification and data extraction process involved reviewing centralised electronic health records from public hospitals.…”

Precision medicine in catecholaminergic polymorphic ventricular tachycardia: Recent advances toward personalized care

“…With the rapid and recent advances in the understanding and management of CPVT, this topical review aims to provide the latest updates in molecular genetics, risk stratification, and gene therapy;[ 94 95 ] three areas that have developed substantially over the past few years. From discovering the RyR2 gene mutation initially, studies have now identified and validated seven sets of genes (RyR2, CASQ-2, TRDN, CALM1, 2 and 3, and TECRL) responsible for various CPVT phenotypes with novel insights into each gene’s molecular mechanisms.…”