Feasibility and efficacy of vascular closure device for sealing uterine entry site: preliminary results from pregnant sheep model.

Abstract

Membrane damage at or near the uterine entry site is a prevalent complication of fetal surgery and may result in chorioamniotic separation (CAS), preterm prelabor rupture of membranes (PPROM) and preterm birth. Transamniotic transuterine suturing approaches offer the potential to reduce the prevalence of CAS and PPROM accompanying fetoscopy, with the overarching aim of reducing preterm birth. This study aimed to explore the feasibility and potential efficacy of employing a novel vascular closure device for transamniotic transuterine suturing in a sheep model of fetoscopic surgery. This study employed a pregnant sheep model to simulate fetal surgery and was conducted between December 2023 and February 2025. We used multiple methodologies to evaluate the Abbott Perclose™ vascular closure device for suturing membranes at the uterine entry site before or after the insertion of a 12-French outer diameter cannula. Feasibility was defined as successful suture placement by two independent surgical teams at two different gestational ages. Potential efficacy was demonstrated by the watertight closure of the entry site during in-vivo gross examination, along with organizing fibrosis and healing of membranes and myometrium, as assessed by postdelivery histopathological evaluation. The procedures were conducted in two phases during the sheep's gestation. Three approaches were used for abdominal entry to access the uterus: midline laparotomy and direct uterine entry; 2-cm mini laparotomy allowing access to the uterus; and a percutaneous approach. Histopathological examination of samples from the entry sites was conducted using routine microscopy, trichrome staining and immunohistochemistry for Connexin 43 (Cx43). This study was approved by the Institutional Animal Care and Use Committee (AN-2010). Ten pregnant sheep were included in this study, four of which had a twin pregnancy. The median gestational age at the occurrence of the first and second rounds of intervention was 85.5 and 104 days, respectively. Overall, 32 Perclose devices were used, and 75% (24/32) were placed successfully. Watertight closure of all sutures was observed during the first and second rounds of intervention, at Cesarean delivery and in situ. Histopathological examination confirmed organizing fibrosis surrounding the device entry site, in addition to overexpression of Cx43. Employing multiple orthogonal approaches, we have shown for the first time that the Perclose device is both feasible and potentially efficacious as a novel means of uterine port closure in our preclinical sheep model of fetoscopic surgery. Inspired by our success in this preclinical model, we anticipate that clinical validation studies will provide translational data and a direct means of measuring efficacy in the reduction of CAS, PPROM and preterm birth. © 2025 International Society of Ultrasound in Obstetrics and Gynecology.