Pregnancy outcome and placental characteristics of twin-to-twin transfusion syndrome with different vascular patterns following fetoscopic laser surgery / 中华围产医学杂志

ABSTRACT

Objective:To evaluate the effect of different superficial vascular patterns on pregnancy outcome and residual anastomosis following laser coagulation in placentae with twin-to-twin transfusion syndrome (TTTS).Methods:This study retrospectively collected and analyzed the clinical data and postnatal placenta perfusion characteristics of 57 cases of TTTS who received fetoscopic laser occlusion of chorioangiopagous vessels (FLOC) and delivered at Peking University Third Hospital from April 2014 to April 2019. According to the vascular pattern, all the cases are divided into four groups, which were parallel, staggered, mixed, and monoamniotic groups. Differences in the operation time and method, pregnancy outcome, and residual vascular anastomosis between the four groups were compared using analysis of variance, non-parametric tests, and Chi-square (or Fisher's exact) tests. Results:Among the 57 cases, the staggered, mixed, parallel, and monoamniotic types were accounted for 68.4%(39/57), 15.8%(19/57), 14.0%(8/57), and 1.7%(1/57), respectively. After exclusion of one case of monoamniotic type, gestational weeks at onset and surgery in the parallel group were both later than the staggered and mixed groups [23.0 (22.0-26.3) weeks vs 21.0 (17.0-24.7) weeks and 22.6 (21.3-23.9) weeks, H=10.306, P=0.006; 25.0 (22.6-26.3) weeks vs 22.0 (17.4-24.9) weeks and 23.2 (22.4-24.0) weeks, H=9.926, P=0.007; all P'<0.016 7]. There was no statistical significance in the differences in operation time and method, gestational age at the end of the pregnancy, neonatal birth weight, or birth weight discordance between the three groups. The diameter of residual vascular anastomosis of women in the staggered group was less than that in the mixed group [0.6 (0.1-5.0) mm vs 1.4 (0.3-5.1) mm, P'<0.016 7], but no significant difference was observed in the parallel-group [0.9 (0.2-3.6) mm] neither with the mixed or staggered group. The staggered group was noted for an increased distance ratio of umbilical cord insertion compared with the parallel and the mixed group [0.66 (0.59-1.00) vs 0.49 (0.25-0.55) and 0.48 (0.42-0.53); P'<0.016 7]. There was no significant difference between the parallel and the mixed groups. Conclusions:Placental superficial vascular patterns may affect the residual vascular anastomosis in women with TTTS following FLOC, which should be thoroughly evaluated before the operation to develop an individual management plan to reduce residual anastomosis incidence.