C0464 - Comparison of Safety of Lumen Apposing Metal Stents With or Without Coaxial Plastic Stent Placement for the Management of Pancreatic Fluid Collections

Introduction: Lumen opposing metal stents (LAMS) allow for safe and effective endoscopic drainage of pancreatic fluid collections (PFCs). LAMS, however, have been associated with bleeding within the cavity and pseudoaneurysm formation. Placement of a coaxial double pigtail plastic stent (DPPS) may theoretically reduce this risk and that of symptomatic stent occlusion. The aim of this study is to compare the safety of LAMS alone versus LAMS with coaxial DPPS placement (LAMS/DPPS) for the management of PFCs.

Methods: Patients who underwent LAMS placement for management of a PFC between Sep 2019 and Feb 2022 were retrospectively identified from a tertiary care center procedural data base. Cases were categorized as LAMS or LAMS/DPPS. Demographics, clinical characteristics, and outcomes were compared between the two cohorts. The primary outcome was the rate and type of adverse events between the groups. Secondary outcomes included clinical success rates and time to clinical success.

Results: 185 unique patients were identified; 83 (44.9%) with LAMS drainage alone and 102 (55.1%) LAMS/DPPS. There were no significant differences in age, sex, PFC etiology, PFC type, size, or paracolic extension (Table 1). DPPS with 7Fr or 10Fr diameters were utilized with a median length of 4.0 cm (IQR 4.0-7.0). There were no significant differences in rates of clinical success, need for early necrosectomy, number of endoscopies, or number of necrosectomies. However, stent dwell time was significantly longer in the LAMS only group (69 vs. 35 days, p=0.017). Overall, AE rates were the same in the two cohorts (15.7%, vs. 15.7%, p=0.825). Bleeding occurred in 2 (2.4%) and 9 (8.8%) cases in the LAMS and LAMS/DPPS groups, respectively (p=0.067), with 4 confirmed cases of pseudoaneurysm bleeding (1 LAMS and 3 LAMS/DPPS, p=0.220). There were no differences in the rate of clinically significant stent occlusion (2.4% LAMS vs. 2.9% LAMS/DPPS, p=0.825) or migration (3.6% LAMS vs. 1.0% LAMS/DPPS, p=0.220). Incidental DPPS migration was noted in 12 (11.8%) cases, but all patients were asymptomatic.

Discussion: The safety profile of LAMS was similar to LAMS/DPPS in this cohort. The incidence of bleeding and occlusion was low overall and not significantly impacted by the presence of a DPPS. Randomized studies are needed to further elucidate the role of coaxial DPPS in drainage of PFCs.