Hemodynamic changes with phenotype reversal during pregnancy in twin-twin transfusion syndrome

Atypical twin-to-twin transfusion syndrome case managed in a single centre in Indonesia with fetoscopic laser photocoagulation and amniopatch: 'Case Report'

Introduction and importance

The diagnostic criteria for Quintero staging in twin-to-twin transfusion syndrome (TTTS) are not applicable in all cases of TTTS, such as those in which the symptoms overlap with other monochorionic twin complications such as selective intrauterine growth restriction (sIUGR).

Case presentation

A 25-year-old woman, G1P0A0, at 22-24 weeks' gestational age was diagnosed with TTTS, with no outstanding history of medication use during pregnancy, and no family history of genetic disorder or twin pregnancy. In the donor twin, persistently absent end-diastolic flow in the umbilical artery was observed using Doppler velocimetry. Polyhydramnios was observed in the recipient twins. The fetal weight discordance between the twins was 39%. After 2 weeks of follow-up, the authors performed fetoscopic laser photocoagulation and successfully ablated five vascular anastomoses and amnioreduction by 2.5 l. Five days after the laser surgery, the patient developed amniotic fluid leakage, and an amniopatch was performed. The authors did the caesarean section at 34 weeks because of severe preeclampsia, the donor and recipient birth weights were 1,120 g and 1,837 g, respectively (weight discordance 39%). The APGAR scores were 3/4 and 6/8, respectively. The donor twin died 6 days after delivery due to respiratory failure, and the recipient twin survived. Neonatal echocardiography of the surviving twin showed no tricuspid regurgitation. No long-term follow-up was performed.

Clinical discussion

The traditional diagnostic criteria for TTTS stage 3 were not met and overlapped with the diagnostic criteria for sIUGR type 2. This is the first procedure reported in Indonesia for atypical TTTS with the outcome, one twin survived.

Conclusion

Some TTTS cases do not meet traditional diagnostic criteria and overlap with other monochorionic twin complications.

Fetal Heart Size: A Comparison Between the Point-to-Point Trace and Automated Ellipse Methods Between 20 and 40 Weeks' Gestation

OBJECTIVES

To evaluate whether the global area and circumference of the heart varies between two measurement techniques: the point-to-point trace and the electronic ellipse methods.

METHODS

The epicardial border of the 4-chamber view was measured in 200 fetuses between 20 and 40 weeks' gestation, from which the area and circumference using the point-to-point trace and electronic ellipse were measured. Analysis of variance, correlation, and regression analysis using fractional polynomials and 7 independent variables (head circumference, biparietal diameter, abdominal circumference, femur length, estimated fetal weight, mean ultrasound gestational age, and last menstrual period gestational age) were performed.

RESULTS

The correlation between the mean ultrasound gestational age and last menstrual period gestational age was 0.9880 (5% confidence limit, 0.9716; 95% confidence limit, 0.9880), with an R² of 0.9762. The R² value for the 7 independent variables regressed against the area and circumference using the point-to-point trace and electronic ellipse methods ranged between 0.885 and 0.965. Comparison of Z scores between this study and previous publications demonstrated that there were differences and similarities, depending on whether the area or circumference was measured.

CONCLUSIONS

This study shows high R² values when comparing measurements of the area and circumference against 7 independent variables, irrespective of whether the point-to-point trace or the electronic ellipse method was used to obtain the measurements. A calculator to evaluate the area and circumference is provided, using 7 independent variables from which Z scores and percentiles for individual measurements can be computed.

Monochorionic twin fetuses showing a reversal of donor-recipient phenotypes in severe twin-twin transfusion syndrome without oligo-polyhydramnios sequence

Antenatal sonographic diagnosis of twin-twin transfusion syndrome (TTTS) is based on findings of a twin oligo-polyhydramnios sequence (TOPS) observed in monochorionic twin fetuses. However, TTTS can develop without a significant characteristic intertwin discordance in the amniotic fluid volumes. We report an uncommon form of TTTS without TOPS showing severe anemia in one twin and polycythemia in the other. Based on sonographic findings, it is considered that the recipient twin became the donor later in gestation, and vice versa. It is concluded therefore that even in the absence of TOPS, the possibility of severe TTTS with a suspected reversal of donor-recipient phenotypes during pregnancy should not be excluded, and serial Doppler studies including the measurement of the middle cerebral artery peak systolic velocity should be routinely performed even in seemingly uncomplicated monochorionic twin fetuses without TOPS.