Late‐gestation prediction of outcome in tricuspid valve dysplasia and Ebstein's anomaly using fetal tricuspid regurgitation waveform analysis.

Objective: To investigate the criteria, based on fetal TR waveforms in late gestation, to predict biventricular circulation (BV) after birth in cases of tricuspid valve dysplasia (TVD) or Ebstein's anomaly diagnosed during the fetal period. Methods: We included 35 consecutive cases diagnosed with TVD or Ebstein's anomaly during the fetal period between January 2008 and December 2021 at Kanagawa Children's Medical Center, Kanagawa, Japan. The maximum velocity and change in pressure over time of tricuspid regurgitation (TR) jet (dP/dt), estimated using TR waveforms obtained during the late‐gestation period (gestational age ≥ 28 weeks), were collected from patient records. dP/dt was calculated by dividing the change in estimated right ventricular pressure obtained using Bernoulli's principle by the time taken for the TR maximum velocity to change from one‐third to two‐thirds of its peak value. The outcome was divided into four categories: BV, single ventricular circulation, neonatal death and fetal death. Patients with BV were included in the BV group, while patients with single ventricular circulation, neonatal death or fetal death were included in the non‐BV (NBV) group. Results: Overall, 19 and 16 patients were included in the BV and NBV groups, respectively. The median TR maximum velocity was 3.3 (range, 2.4–3.6) m/s in the BV group and 1.9 (range, 1.0–3.3) m/s in the NBV group. There were no cases of postnatal BV in fetuses with TR maximum velocity < 2.4 m/s; cases with TR maximum velocity of 2.4–3.3 m/s were observed in both BV and NBV groups. Receiver‐operating‐characteristics‐curve analysis was performed on the 11 patients in the BV group and five patients in the NBV group with a TR maximum velocity of 2.4–3.3 m/s. dP/dt ≥ 350 mmHg/s and TR maximum velocity ≥ 2.9 m/s were identified as criteria for predicting the outcome in such cases. The performance of dP/dt ≥ 350 mmHg/s in predicting BV after birth in fetuses with TVD or Ebstein's anomaly was higher compared to that of TR maximum velocity ≥ 2.9 m/s (sensitivity, 90.9% vs 72.3% and specificity, 80.0% vs 80.0%, respectively). Conclusions: In fetuses with TVD or Ebstein's anomaly, the postnatal outcome may be BV or NBV when the TR maximum velocity is 2.4–3.3 m/s. In such cases, by combining the TR maximum velocity with dP/dt ≥ 350 mmHg/s, BV after birth may be predicted with greater accuracy. © 2022 International Society of Ultrasound in Obstetrics and Gynecology. [ABSTRACT FROM AUTHOR]