A RANDOMIZED TRIAL COMPARING GASTRIC AND COLORECTAL ENDOSCOPIC SUBMUCOSAL DISSECTION DEFECT CLOSURE USING NOVEL THROUGH THE SCOPE SUTURING SYSTEM WITH OVER-THE-SCOPE SUTURING SYSTEM

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.

Background and Aims:
Bleeding and delayed perforation are two known complications from endoscopic submucosal dissection (ESD) which can be reduced with mucosal closure. Mucosal closure, however, further prolongs a lengthy ESD procedure. One of the mucosal closure devices that has been studied in the past is over the scope endoscopic suturing system (OTSS). A novel through-the-scope endoscopic helix tack suture system (TTSS) is now available. We aim to compare the closure time, technical and clinical success, and cost effectiveness between OTSS and TTSS.

Methods:
This is a single center, prospective, randomized trial. All patients having ESD with anticipated closure were randomized 1:1 to closure with either the TTSS (the study group) or the OTSS (the control group.) The primary outcome was the “closure time” (CT) defined as the time between first bite/tack and the last cinch/endoclip. A related measure called “overall closure time” (OCT) was defined as time between the end of dissection to the last cinch/endoclip and this represented setup and closure time. Secondary outcomes included the rates of technical success, closure related adverse events and cost effectiveness.

Results:
40 patients were randomized (20 each to OTSS and TTSS). There was no significant difference between groups in baseline characteristics such as mean age in years (62.2 vs. 61.8, P=0.92), male gender (55% vs. 50%, P=0.75), proportion of colorectal polyps (80% vs. 85%, P=0.91), right colon polyps (20% vs. 30%, P=0.72) and mean size of resected specimen in mm (40.9 ±17.0 x 29.8 ±12.7 vs. 40.4±17.5 x 26.0 ±8.5). Closure with primary device was successful in 17 (85%) cases in OTSS group and 18 (90%) cases in TTSS group (P=0.63). There was no significant difference in mean CT between groups (18.4 ±16.9 mins for OTSS vs. 23.3 ±13.9 mins for TTSS ,P=0.36). Mean OCT for OTSS was 32.0 ±21.7 mins vs. 39.5 ±20.9 mins for TTSS (P=0.31). No closure related intraprocedural complications were noted. Two episodes of self-limited delayed bleeding occurred with resumption of antiplatelets in patients with OTSS failures (one had been partially closed with endoclips, the other crossed over to TTSS). Of the lesions located in the right colon, closure with primary device was achieved in two out of four cases (50%) in OTSS group compared to all six cases in TTSS group (100%) (P=0.13). No delayed perforations were noted. Mean total cost of closure was not significantly different between groups (P=0.61) but was significantly lower in TTSS group for lesions <35mm in length (P=0.008).

Conclusion:
When used for gastric and colorectal ESD defect closure, the novel TTSS has similar closure time, efficacy and adverse events compared to OTSS. TTSS is a valuable closure tool in OTSS inaccessible areas such as proximal colon. TTSS is more cost effective for closure of lesions smaller than 35mm.