Management of twin-reversed arterial perfusion (TRAP) sequence: a systematic review and meta-analysis.

Introduction: Twin reversed arterial perfusion (TRAP) sequence is a rare complication of monochorionic twin pregnancies characterized by placental anastomoses between a normally developed twin and an acardiac mass. Though several treatment modalities exist, the optimal management strategy is unclear. This study aims to compare the various treatment strategies for TRAP sequence.

Methods: A systematic review of the literature was performed using PRISMA guidelines including PubMed, Scopus, Web of Science and the Cochrane Library. Studies were imported into Covidence, where they were independently screened by two authors. Studies included described interventions for TRAP sequence. Those excluded were unavailable in English and lacked differentiation between intervention strategies for TRAP and other monochorionic twin pregnancies. Fisher's exact test and random effects modeling were used for statistical analysis.

Results: 2340 abstracts were screened, of which 218 articles progressed to full review and 120 qualified for data extraction. 757 twin pregnancies were described. Most were treated with radiofrequency ablation (RFA) (n=363, 47.95%) and laser ablation (n=220, 29.06%). Statistically significant differences amongst the modalities were seen in technical success (p = 0.005), gestational age at presentation (p < 0.01), intervention (p = 0.01), and delivery (p = 0.01), respectively, and time between treatment and delivery (p < 0.01). Notably, pump twin survival did not differ based on treatment modality used (p = 0.196). Overall, complication rates were low with no differences in preterm premature rupture of membranes (PPROM) (p = 0.66), preterm labor (p = 0.58) or maternal hemorrhage between modalities (p = 0.28). Suture cord ligation, however, had a greater hemorrhage rate than RFA (p = 0.03).

Conclusions: This embodies the first meta-analysis comparing treatment modalities for TRAP sequence with outcomes and complications. RFA is the most technically successful strategy. Prospective data is required to further understand the optimal modality and gestational age at treatment to ensure best overall outcomes. .