Beschreibung:
Long QT syndrome (LQTS) is an inherited arrhythmic disorder associated with suddencardiac death (SCD). This study aimed to identify the clinical and molecular genetic risk factors thatcontribute to major arrhythmic events (MAEs) in patients with genetically confirmed childhood onsetLQTS 1–3. This study was a retrospective double-center study. An MAE was defined as the occurrenceof SCD, aborted SCD, appropriate implantable cardioverter defibrillator discharge, or sustainedventricular tachycardia. During a median follow-up of 4.6 years (range 0.1–24.3 years), MAEs occurredin 18 (17.8%) of 101 patients diagnosed with LQTS at a median of 7.7 years (range 0.0–18.0 years)despite the use of beta-blockers in 91.6% of patients at the last follow-up. A multivariate analysisidentified a genetic diagnosis of LQTS2 and LQTS3 and variants within the KCNH2 S5-loop-S6pore region as independent risk factors for MAEs, independent of the QTc value or a history ofsyncope detected from a univariate analysis. MAEs occur frequently in childhood onset LQTS despitebeta-blocker treatment. A detailed molecular genetic diagnosis can contribute to the arrhythmia riskstratification and optimize the use of preventive measures in this vulnerable patient population