Arrhythmias & electrophysiologyCross-sectional study
Clinical Characteristics and Transplacental Treatment of Fetal Ventricular Tachycardia: A Nationwide Survey in Japan
- nationwide survey
- 77 tertiary referral facilities in Japan
- 2014–2023
Authors' conclusion
Transplacental treatment is highly recommended for preterm fetal VT. In particular, in cases of fetal VT diagnosed before 33 weeks of gestation, aggressive fetal treatment including magnesium sulfate and β-blockers should be considered with the possibility of LQT 2 or 3.
Study context
- Population
- Cases of suspected fetal ventricular tachycardia in Japanfetal ventricular tachycardia (VT) cases from 18 facilities
- Participants
- 24 cases
- Exposure
- Long QT syndrome (LQTS) vs non-LQTS fetal VT cases
- LQTSn = nine
- non-LQTSn = 15
Main finding
As reported in the abstract
Diagnosis
Diagnosed based on atrioventricular dissociation
Twenty cases
Initially diagnosed as supraventricular tachycardia
Four
Observational data: associations, not effects.
Further findings
| Outcome | LQTS | non-LQTS |
|---|---|---|
| Timing of VT onset | VT occurred by 32 6/7 weeks of gestation in all nine | 8/15 occurred at term |
| Effectiveness of fetal treatment | 8/9 | Not reported in the abstract |
| Refractory to treatment after birth · requiring multidisciplinary management | 8/9 | 6/14 |
| Neurodevelopmental delay | 6/9 | 2/14 |
- Effectiveness of fetal treatment — Effective overall
- 9/11
Receipt of fetal treatment
- Cases managed as fetal VT receiving fetal treatment
- Eight of 20
- Cases managed as fetal supraventricular tachycardia receiving fetal treatment
- three of four
Safety
Side effects of fetal treatment
- Side effects observed
- 6/11
- Serious adverse events: none except one case of lidocaine toxicity
- one
Original publication
Clinical Characteristics and Transplacental Treatment of Fetal Ventricular Tachycardia: A Nationwide Survey in Japan. Heart Rhythm. Published 9 October 2026. doi:10.1016/j.hrthm.2026.10.005
Summarised from the published abstract; every number is checked against it