Trophoblastic microcirculation occlusion as an adjunct to electric vacuum aspiration for the treatment of endogenous cesarean scar pregnancy

Abstract

To describe a simple adjunct treatment option, trophoblastic microcirculation occlusion (TMO), which could change subsequent high-risk electric vacuum aspiration in patients with an endogenous cesarean scar pregnancy (CSP) into a routine conventional surgical procedure. Electric vacuum aspiration for the treatment of CSP may be associated with several significant complications, including hemorrhage and tissue remnants. Consequently, a second intervention, such as uterine artery embolization, resectoscopy, or methotrexate, may be required, thus complicating the surgical treatment of CSP. We demonstrate the principle and detailed technique of TMO treatment using animations, video clips, and slides. The study was approved by the institutional review board of Hangzhou Women's Hospital. Tertiary maternity hospital. The video shows a 30-year-old woman with a 5-week endogenous CSP. The procedural steps were repeated in another 6 patients suffering from endogenous CSP (Table1). Written informed consent was obtained from each patient. In patients with a CSP, the syncytiotrophoblastic cells erode the helicine arteries in the inner uterine myometrium. The cytotrophoblastic cells extend as villi tissue into the syncytiotrophoblast. Maternal blood enters the intervillous space between the cytotrophoblast and syncytiotrophoblast. The syncytiotrophoblast, cytotrophoblast, and intervillous space constitute the trophoblastic microcirculation, which subsequently becomes the main blood supply to the gestational sac (Fig.1). During TMO treatment, the trophoblastic microcirculation is identified by contrast-enhanced ultrasound with the cubital vein injected with sulfur hexafluoride microbubbles (Bracco, Switzerland). A 21-gauge needle (200 mm long) was punctured vaginally into the uterine myometrium surrounding the syncytiotrophoblast at 3 different points, and a total of 8 mL sclerosant was injected directly to seal the trophoblastic microcirculation. Complete compression of the helicine arteries for trophoblastic blood supply is the key to TMO treatment (Fig.2, see video interpretation for detailed information). A repeat contrast-enhanced ultrasound was performed after injection to confirm a significant reduction of blood flow in the trophoblast. An electric vacuum aspiration was performed 24 hours after TMO treatment to remove the products of conception completely. Surgical safety was enhanced by deep sedation and concurrent transabdominal ultrasound guidance. The levels of β-human chorionic gonadotropin (β-hCG) were measured weekly until a nonpregnant level was achieved. A follow-up ultrasound then was performed to confirm that the treatment was complete. The clinical value and feasibility of TMO treatment as an adjunct before high-risk electric vacuum aspiration for the management of endogenous CSP. The TMO treatment was performed successfully in all 7 patients; the clinical outcomes are presented in Table2. The TMO treatment significantly reduced the risk of hemorrhage during electric vacuum aspiration. No complications were detected perioperatively. Patients were discharged on day 1 postoperatively. Follow-up ultrasound, performed when the levels of β-hCG had fallen to normal, failed to identify any remnants of the uterine corpus. One patient achieved an intrauterine pregnancy 7 months postoperatively and gave birth to a live baby at 39 weeks of gestation via repeat cesarean section. No cesarean scar dehiscence was observed. Surgical abortion of an endogenous CSP, with a high risk of intraoperative hemorrhage, can be performed with minimal blood loss in a single electric vacuum aspiration when assisted by TMO treatment. This technique provides good results in terms of bleeding reduction that are comparable to those in conventional patients. The TMO treatment can be accomplished via ultrasound-guided needle puncture, a technique that is available widely in the practice of reproductive medicine with a reduced need for consumable resources. The use of a simple adjunct treatment option, TMO, expands the indications of electric vacuum aspiration. This sequential treatment allows for completion of clinical management without the need for uterine artery embolization, resectoscopy, or methotrexate, thus simplifying the originally complicated form of surgical treatment for CSP.