COMPARISON OF THE NOVEL THROUGH-THE-SCOPE (TTS) SUTURE SYSTEM VERSUS THE OVER-THE-SCOPE (OTS) SUTURE DEVICE FOR MUCOSAL INCISION CLOSURE AFTER GASTRIC PER-ORAL ENDOSCOPIC MYOTOMY (G-POEM): A MULTI-CENTER STUDY

Background: G-POEM has emerged as a treatment for medically refractory gastroparesis. Safe and effective mucosal closure is necessary to avoid potential morbidity. The aim of this study was to compare outcomes between the novel through-the-scope (TTS) suture system (X-Tack, Apollo, EndoSurgery) and the existing over-the-scope (OTS) endoscopic suture device (Overstitch, Apollo Endosurgery) for mucosal incision closure after G-POEM.
Methods: Dual-center retrospective analysis of prospective databases on consecutive patients who underwent G-POEM with mucosal incision closure with either the TTS or OTS suturing systems from September 2018 to September 2022. Primary outcomes were the proportion of patients with complete closure and endoscopic suturing technical success. Failed closure was defined as incomplete closure based on contrast extravasation on post-procedural imaging or incomplete closure-related adverse events. Endoscopic suturing technical success was defined as complete mucosal closure with the TTS or OTS suture alone. Secondary outcomes included closure time and adverse events.
Results: One-hundred twenty patients (mean age 51.4 ± 13.8 years; 80% women; mean gastroparesis cardinal symptom index score of 3.2 ± 1.1) underwent G-POEM with mucosal incision closure with TTS (n=36) or OTS (n=84) suturing. G-POEM technical success was 100%. Table 1 summarizes characteristics between the TTS vs OTS suture groups. A transverse mucosal incision was performed for most cases (97.2% in TTS and 100% in OTS suturing groups; p=0.3). There were no statistically significant differences in the length of mucosal incision, submucosal tunneling or pyloromyotomy between the two groups. Procedural times between TTS and OTS suturing were as follows: mucosal incision closure (17.5 ± 10.8 vs. 12.2 ± 4.8 min; p=0.6) and total procedure (48.4 ± 16.8 vs. 59.4 ± 9.9 min; p=0.6), respectively. Complete closure was achieved in 100% (36/36) and 98.8% (83/84) in the TTS and OTS suture groups, respectively (p=1.0). In the single case of failed closure, subsequent complete closure was achieved with TTS clips. Endoscopic suturing technical success was significantly higher with OTS as compared to TTS suturing (91.7% vs 66.7%; p=0.002), with adjunct TTS clips used for complete closure in all remaining cases. There was 1 case of perforation in the OTS suturing group (0.8%) which required surgical intervention with full recovery.
Conclusion: The novel TTS suture system is safe and effective for mucosal incision closure after G-POEM. There was no difference in complete closure rate or procedural times between TTS and OTS suturing. Patients who underwent OTS suturing were less likely to require additional adjunct TTS clips for complete closure when compared to the TTS suture system. Additional prospective comparative trials and cost-effectiveness analyses are warranted.