Arrhythmias & electrophysiologyCohort study
Long QT syndrome in children and adolescents: risk factors and outcomes in a large German cohort
- Retrospective cohort study
- multicentre
- 12 German tertiary care centres
Authors' conclusion
Paediatric LQTS patients are at risk for life-threatening arrhythmias at <18 years of age
Study context
- Population
- Children and adolescents with long QT syndrome (LQTS), Germany
- Participants
- 548 children
- Outcome
- Major arrhythmic event:
- SCD
- Aborted cardiac arrest
- Appropriate ICD therapy
- Follow-up
- Before age 18 years
Main finding
As reported in the abstract
Major arrhythmic event
- Primary outcome reached
- 58 patients (10.6%)
- Sudden cardiac death (SCD)
- 7 (1.3%)
- Aborted cardiac arrest
- 40 (7.3%)
- Appropriate implantable cardioverter-defibrillator (ICD) therapy
- 11 (2.0%)
- Overall event rate
- 1.0 per 100 patient-years at risk
Observational data: associations, not effects.
Further findings
Risk factors for major arrhythmic event (multivariate analysis)
| Comparison | HR (95% CI) | P value | |
|---|---|---|---|
| LQT3 | 2.5 (1.1–5.6) | P = 0.03 | |
| Syncope | 3.0 (1.7–5.5) | P < 0.01 | |
| Absence of cardiac medication | 9.5 (5.3–17.3) | P < 0.01 | |
| QTc ≥500 ms | 2.9 (1.4–6.3) | P < 0.01 | |
| 0.050.21520Hazard ratio (log scale) |
Risk factors in subanalyses
- Pathogenic variant in KCNH2 pore region (LQT2) and younger age at symptom presentation identified as risk factors
ICD implantation and appropriate therapy · before 18 years of age
- ICD implanted
- 73 patients (13.3%)
- Appropriate therapy among ICD recipients
- 25 (34.2%)
- Received cardiac medication
- 92.1%
Original publication
Long QT syndrome in children and adolescents: risk factors and outcomes in a large German cohort. Eur Heart J. Published 2 July 2025. doi:10.1093/eurheartj/ehaf365
Summarised from the published abstract; every number is checked against it