Arrhythmias & electrophysiologyCohort study
Effects of cohort, genotype, variant, and maternal β-blocker treatment on foetal heart rate predictors of inherited long QT syndrome
- Cohort study
- international
Authors' conclusion
Genotype, LQT1 variant, and maternal β-blocker therapy affect FHR. A predictive threshold of FHR/GA significantly improves the accuracy, sensitivity, and specificity for LQT1 and LQT2, above the infant's a priori 50% probability.
Study context
- Population
- Pregnancies in which one parent had long QT syndrome (LQTS)164 LQTS families
- Participants
- 267 pregnancies
- Exposure
- Foetal heart rate (FHR) by LQTS genotype, variant and maternal β-blocker therapy
- LQT1n = 220
- LQT2n = 35
- LQT3n = 12
- Outcome
- FHR by genotype, variant and maternal β-blocker therapy; FHR/gestational age (GA) threshold for LQTS
- Follow-up
- 7-42 weeks' GA
Main finding
As reported in the abstract
FHR
- FHR significantly lower in LQT1 and LQT2 but not LQT3 or LQTS negative
- LQT1 variants with non-nonsense and severe function loss had lower FHR
- Maternal β-blockers potentiated bradycardia in LQT1 and LQT2 but did not affect FHR in LQTS negative
Observational data: associations, not effects.
Further findings
| Outcome | Values |
|---|---|
| FHR/GA threshold for predicting LQT1 and LQT2 | FHR/GA threshold accuracy 74.9% · sensitivity 71% · specificity 81% |
Original publication
Effects of cohort, genotype, variant, and maternal β-blocker treatment on foetal heart rate predictors of inherited long QT syndrome. Europace. Published 17 November 2023. doi:10.1093/europace/euad319
Summarised from the published abstract; every number is checked against it