Feasibility, safety, and outcomes of a single-step endoscopic ultrasonography-guided drainage of pancreatic fluid collections without fluoroscopy using a novel electrocautery-enhanced lumen-apposing, self-expanding metal stent

Endoscopic Drainage of Pancreatic Fluid Collections

Pancreatic fluid collections (PFCs) are commonly encountered complications of acute and chronic pancreatitis. With the advancement of endoscopic ultrasound (EUS) techniques and devices, EUS-directed transmural drainage of symptomatic or infected PFCs has become the standard of care. Traditionally, plastic stents have been used for drainage, although lumen-apposing metal stents (LAMSs) are now favored by most endoscopists due to ease of use and reduced procedure time. While safety has been repeatedly demonstrated, follow-up care for these patients is critical as delayed adverse events of indwelling drains are known to occur.

International Consensus Recommendations for Safe Use of LAMS for On- and Off-Label Indications Using a Modified Delphi Process

INTRODUCTION

The study aimed to develop international consensus recommendations on the safe use of lumen-apposing metal stents (LAMSs) for on- and off-label indications.

METHODS

Based on the available literature, statements were formulated and grouped into the following categories: general safety measures, peripancreatic fluid collections, endoscopic ultrasound (EUS)-biliary drainage, EUS-gallbladder drainage, EUS-gastroenterostomy, and gastric access temporary for endoscopy. The evidence level of each statement was determined using the Grading of Recommendations Assessment, Development, and Evaluation methodology.International LAMS experts were invited to participate in a modified Delphi process. When no 80% consensus was reached, the statement was modified based on expert feedback. Statements were rejected if no consensus was reached after the third Delphi round.

RESULTS

Fifty-six (93.3%) of 60 formulated statements were accepted, of which 35 (58.3%) in the first round. Consensus was reached on the optimal learning path, preprocedural imaging, the need for airway protection and essential safety measures during the procedure, such as the use of Doppler, and measurement of the distance between the gastrointestinal lumen and the target structure. Specific consensus recommendations were generated for the different LAMS indications, covering, among others, careful patient selection, the preferred size of the LAMS, the need for antibiotics, the preferred anatomic location of the LAMS, the need for coaxial pigtail placement, and the appropriate management of LAMS-related adverse events.

DISCUSSION

Through a modified international Delphi process, we developed general and indication-specific experience- and evidence-based recommendations on the safe use of LAMS.

Lumen-apposing metal stents versus traditional self-expanding metal stents for endoscopic ultrasound-guided drainage of pancreatic fluid collections: a systematic review and meta-analysis

BACKGROUND

Endoscopic drainage has become the preferred treatment for pancreatic fluid collections (PFCs). There is still a lack of reliable evidence to prove which metal stent is the best choice for endoscopic ultrasound (EUS)-guided drainage of PFCs. In this study, we aimed to evaluate the efficacy and safety of lumen-apposing metal stents (LAMS) compared to traditional self-expanding metal stents (SEMS) in meta-analysis.

METHODS

We systematically searched PubMed, Embase, Web of Science, and Cochrane Library up to July 15, 2023. Relevant publications that compared LAMS with traditional SEMS for drainage of patients' PFCs under EUS-guidance were included. This meta-analysis assessed endpoints using Review Manager 5.3 and Stata 14.0 statistical software.

RESULT

Nine citations comprising 707 patients with PFCs were included. The clinical success rate of LAMS tended to be higher than that of SEMS (RR = 1.07, 95%CI [1.00, 1.15], P = 0.05). LAMS had a lower technical success rate (RR = 0.97, 95%CI [0.94, 0.99], P = 0.02) and faster procedure time (minutes) (MD =  - 24.29, 95%CI [- 25.59, - 22.99], P < 0.00001) compared to SEMS. In addition, LAMS had fewer overall adverse events (RR = 0.64, 95%CI [0.48, 0.87], P = 0.004). For specific adverse events, LAMS had fewer migration (RR = 0.37, 95%CI [0.19, 0.72], P = 0.003), occlusion (RR = 0.43, 95%CI [0.22, 0.82], P = 0.01) and infection (RR = 0.38, 95%CI [0.20, 0.70], P = 0.002). There was no significant difference in bleeding and perforation between the two stents. For hospital stay (days), LAMS group was similar to SEMS group (MD =  - 3.34, 95%CI [- 7.71, - 1.03], P = 0.13). Regarding recurrence, LAMS group was fewer than SEMS group (RR = 0.41, 95%CI [0.21, 0.78], P = 0.007).

CONCLUSION

Compared to traditional SEMS, LAMS has a higher clinical success rate, faster procedure time, fewer adverse events, similar hospital stay and lower recurrence rate in EUS-guided drainage of PFCs. LAMS is a good choice with a high technical success rate over 95%, and using a shorter length or "one-step" operation can further improve it. Richer placement experience is required for LAMS placement under EUS-guidance.

Endoscopic ultrasound-guided drainage of pancreatic collections with dedicated metal stents: A nationwide, multicenter, propensity score-matched comparison

BACKGROUND

The new dedicated stents for endoscopic ultrasound (EUS)-guided transluminal drainage of peri‑pancreatic fluid collections (PFCs) demonstrated optimal efficacy and safety profiles.

AIMS

This study aimed to evaluate the safety, technical and clinical success, and recurrence rate of PFCs drained with Lumen Apposing Metal Stent (LAMS) or Bi-Flanged Metal Stent (BFMS).

METHODS

Data from a multicenter series of PFCs treated with LAMS or BFMS at 30 Italian centers during a 5-year period were retrieved. The rate of adverse events (AEs), technical success, clinical success, PFC recurrence were evaluated. To overcome biases, a 1-to-1 match was created using propensity score analysis.

RESULTS

Out of 476 patients, 386 were treated with LAMS and 90 with BFMS, with a median follow-up of 290 days (95% CI 244 to 361). Using propensity score matching, 84 patients were assigned to each group. The incidence of AEs did not differ between the two stents (13.1% versus 15.5%, p = 0.29), mainly bleeding or recurrence rate (4.7% versus 3.5%, p = 1). Technical and clinical success in the BFMS and LAMS groups were 92% versus 95% (p = 0.36) and 91% versus 94% (p = 0.64), respectively.

CONCLUSION

Our study demonstrates that LAMS and BFMS have comparable safety profiles with similar technical and clinical success rates for EUS-guided PFC drainage.

Lumen-apposing-metal stent misdeployment in endoscopic ultrasound-guided drainages: A systematic review focusing on issues and rescue management

BACKGROUND

The introduction of lumen-apposing metal stents (LAMS) for endoscopic ultrasound (EUS)-guided drainages has marked a turning point in the field of interventional ultrasound and it is gathering worldwide diffusion in different clinical settings. Nevertheless, the procedure may conceal unexpected pitfalls. LAMS misdeployment is the most frequent cause of technical failure and it can be considered a procedure-related adverse event when it hampers the conclusion of the planned procedure or results in significant clinical consequences. Stent misdeployment can be managed successfully by endoscopic rescue maneuvers to allow the completion of the procedure. To date, no standardized indication is available to guide an appropriate rescue strategy depending on the type of procedure or of misdeployment.

AIM

To evaluate the incidence of LAMS misdeployment during EUS-guided choledochoduodenostomy (EUS-CDS), gallbladder drainage (EUS-GBD) and pancreatic fluid collections drainage (EUS-PFC) and to describe the endoscopic rescue strategies adopted under the circumstance.

METHODS

We conducted a systematic review of the literature on PubMed by searching for studies published up to October 2022. The search was carried out using the exploded medical subject heading terms “lumen apposing metal stent”, “LAMS”, “endoscopic ultrasound” and “choledochoduodenostomy” or “gallbladder” or “pancreatic fluid collections”. We included in the review on-label EUS-guided procedures namely EUS-CDS, EUS-GBD and EUS-PFC. Only those publications reporting EUS-guided LAMS positioning were considered. The studies reporting a technical success rate of 100% and other procedure-related adverse events were considered to calculate the overall rate of LAMS misdeployment, while studies not reporting the causes of technical failure were excluded. Case reports were considered only for the extraction of data regarding the issues of misdeployment and rescue techniques. The following data were collected from each study: Author, year of publication, study design, study population, clinical indication, technical success, reported number of misdeployment, stent type and size, flange misdeployed and type of rescue strategy.

RESULTS

The overall technical success rate of EUS-CDS, EUS-GBD and EUS-PFC was 93.7%, 96.1%, and 98.1% respectively. Significant rates of LAMS misdeployment have been reported for EUS-CDS, EUS-GBD and EUS-PFC drainage, respectively 5.8%, 3.4%, and 2.0%. Endoscopic rescue treatment was feasible in 86.8%, 80%, and 96.8% of cases. Non endoscopic rescue strategies were required only in 10.3%, 16% and 3.2% for EUS-CDS, EUS-GBD, and EUS-PFC. The endoscopic rescue techniques described were over-the-wire deployment of a new stent through the created fistula tract in 44.1%, 8% and 64.5% and stent-in-stent in 23.5%, 60%, and 12.9%, respectively for EUS-CDS, EUS-GBD, and EUS-PFC. Further therapeutic option were endoscopic rendezvous in 11.8% of EUS-CDS and repeated procedure of EUS-guided drainage in 16.1% of EUS-PFC.

CONCLUSION

LAMS misdeployment is a relatively common adverse event in EUS-guided drainages. There is no consensus on the best rescue approach in these cases and the choice is often made by the endoscopist relying upon the clinical scenario, anatomical characteristics, and local expertise. In this review, we investigated the misdeployment of LAMS for each of the on-label indications focusing on the rescue therapies used, with the aim of providing useful data for endoscopists and to improve patient outcomes.

The Role of Lumen Apposing Metal Stents in the Palliation of Distal Malignant Biliary Distal Obstruction

Malignant biliary obstruction (DMBO) has been traditionally managed by endoscopic retrograde cholangiopancreatography (ERCP). In the case of ERC failure, percutaneous transhepatic biliary drainage (PT-BD) has been widely utilized as a salvage procedure. However, over the last decade, endoscopic ultrasound-guided biliary drainage (EUS-BD) has gained increasing popularity, especially after the advent of electrocautery-enhanced lumen apposing metal stent devices (EC-LAMSs) which enable a one-step procedure, granting prevention of biliary leakage and minimizing occurrence of adverse events (AEs). In parallel, increasing evidence suggests a possible role of EUS-BD in the management of DMBO as a primary palliative drainage modality. In the current paper, we aim to review all the available evidence on the role of EUS-BD performed with EC-LAMSs and discuss salient technical aspects of this type of procedure.

Endoscopic transluminal drainage and necrosectomy for infected necrotizing pancreatitis: Progress and challenges

Infected necrotizing pancreatitis (INP) represents a severe condition in patients with acute pancreatitis. Invasive interventions are recommended in symptomatic INP. Growing evidence has suggested interventional strategies of INP evolving from traditional surgery to minimally invasive step-up endoscopic procedures. However, there is still no standardized protocol for endoscopic interventions. Recently, various studies have been published about the endoscopic management of INP. This article reviews published articles and guidelines to present the progress and challenges of endoscopic transluminal drainage and necrosectomy in INP.

Endoscopic transluminal drainage and necrosectomy for infected necrotizing pancreatitis: Progress and challenges

Infected necrotizing pancreatitis (INP) represents a severe condition in patients with acute pancreatitis. Invasive interventions are recommended in symptomatic INP. Growing evidence has suggested interventional strategies of INP evolving from traditional surgery to minimally invasive step-up endoscopic procedures. However, there is still no standardized protocol for endoscopic interventions. Recently, various studies have been published about the endoscopic management of INP. This article reviews published articles and guidelines to present the progress and challenges of endoscopic transluminal drainage and necrosectomy in INP.

Endoscopic transluminal drainage and necrosectomy for infected necrotizing pancreatitis: Progress and challenges

Infected necrotizing pancreatitis (INP) represents a severe condition in patients with acute pancreatitis. Invasive interventions are recommended in symptomatic INP. Growing evidence has suggested interventional strategies of INP evolving from traditional surgery to minimally invasive step-up endoscopic procedures. However, there is still no standardized protocol for endoscopic interventions. Recently, various studies have been published about the endoscopic management of INP. This article reviews published articles and guidelines to present the progress and challenges of endoscopic transluminal drainage and necrosectomy in INP.

Electrocautery-enhanced Lumen-apposing Metal Stents in the Management of Symptomatic Pancreatic Fluid Collections: Results From the Multicenter Prospective Pivotal Trial

BACKGROUND AND AIMS

Endoscopic decompression is considered a first-line treatment for symptomatic pancreatic fluid collections (PFCs). A lumen-apposing metal stent (LAMS) with an electrocautery-enhanced delivery system [electrocautery-enhanced lumen-apposing metal stent (ELAMS)] may facilitate this procedure. This study evaluated the safety and efficacy of ELAMS in the management of symptomatic PFCs.

PATIENTS AND METHODS

A multicenter, nonblinded, prospective, Food and Drug Administration (FDA)-approved, investigational device exemption clinical trial was conducted. Enrollment criteria included symptomatic PFCs ≥6 cm with ≥70% fluid fraction. Subjects were followed prospectively for safety, efficacy, and resolution of the collections. Primary endpoint success was defined as ≥50% reduction in PFC size. Clinical outcomes were compared with our previously published series of LAMS without the cautery-enhanced delivery system.

RESULTS

The target enrollment of 30 patients was achieved in 7 US tertiary care centers. All patients underwent successful placement of the ELAMS. The mean procedure duration, stent placement time, and fluoroscopy exposures were 28.1±12.5, 5.8±2.6, and 1.8±1.6 minutes, respectively. Eight patients had no fluoroscopy. The primary endpoint was achieved in 83.3% of patients. Two adverse events were attributed to the ELAMS: 1 bleeding upon stent removal and 1 stent migration. Relative to the comparator noncautery LAMS multicenter trial (N=33, 8 tertiary centers), there was a significantly shorter procedure duration [36 min ( P <0.001)] with similar technical and clinical outcomes in the ELAMS cohort.

CONCLUSION

LAMS placed using an electrocautery delivery system significantly reduce procedure duration and were safe and effective in the management of symptomatic PFCs.

Early endoscopic treatment of symptomatic pancreatic necrotic collections

EUS-guided transmural endoscopic drainage is commonly used in the treatment of WOPN in the late phase of ANP. The role of endoscopic intervention remains unclear in the early phase of ANP. This study aimed to prospectively evaluate early endoscopic treatment of ANCs compared with endoscopic drainage of WOPN. Overall, 71 patients with ANP who underwent transmural endoscopic drainage for necrotic collections were included. Endoscopic intervention was performed within the first four weeks of ANP in 25 (35.21%) patients with ANC (Group 1) and in 46 (64.79%) patients after four weeks since the onset of ANP with WOPN (Group 2). The overall mean age of patients was 49.9 (22–79) years and 59 of them were males. The mean time of active drainage and duration of total endoscopic treatment was 26.8 and 16.9 days (P = 0.0001) and 270.8 and 164.2 days (P = 0.0001) in Groups 1 and 2, respectively. The average total number of endoscopic interventions was 9.5 and 4.5 in Groups 1 and 2, respectively (P = 0.0001). The clinical success rate, frequency of complications of endoscopic interventions, long-term success rate, and recurrence rate were not significantly different between the groups (P > 0.05 for each). Transmural endoscopic drainage is effective method of treatment of early ANCs within the first four weeks of ANP. However, compared with endoscopic intervention in WOPN, more interventions and longer duration of drainage are required.

Endoscopic Transmural Drainage and Necrosectomy in Acute Necrotizing Pancreatitis: A Review

Acute necrotizing pancreatitis occurs in 10%–20% of patients with acute pancreatitis (AP) which is one of the most important acute abdominal diseases that require hospital admission. Pancreatic necrosis is also associated with high mortality and morbidity. In the past 20 years, the treatment of pancreatic necrosis has shifted from open necrosectomy to minimally invasive techniques, such as endoscopic interventions. With the development of endoscopic techniques, the safety and effectiveness of endoscopic interventions have improved, but there exist several unresolved problems. Currently, there is no unified standard approach for endoscopic treatment of pancreatic necrosis that takes into account local expertise, anatomical features of necrosis, patients’ preferences, and comorbidity profile. We reviewed the current status of endoscopic therapy for acute necrotizing pancreatitis, focusing on the new endoscopic drainage technique and necrosectomy protocol.

Comparison of safety, efficacy, and long-term follow-up between “one-step” and “step-up” approaches for infected pancreatic necrosis

BACKGROUND

Although the “Step-up” strategy is the primary surgical treatment for infected pancreatic necrosis, it is not suitable for all such patients. The “One-step” strategy represents a novel treatment, but the safety, efficacy, and long-term follow-up have not yet been compared between these two approaches.

AIM

To compare the safety, efficacy, and long-term follow-up of two surgical approaches to provide a reference for infected pancreatic necrosis treatment.

METHODS

This was a retrospective analysis of infectious pancreatic necrosis patients who underwent “One-step” or “Step-up” necrosectomy at Xuan Wu Hospital, Capital Medical University, from May 2014 to December 2020. The primary outcome was the composite endpoint of severe complications or death. Patients were followed up every 6 mo after discharge until death or June 30, 2021. Statistical analysis was performed using SPSS 21.0 and GraphPad Prism 8.0, and statistical significance was set at P < 0.05.

RESULTS

One-hundred-and-fifty-eight patients were enrolled, of whom 61 patients underwent “One-step” necrosectomy and 97 patients underwent “Step-up” necrosectomy. During the long-term follow-up period, 40 patients in the “One-step” group and 63 patients in the “Step-up” group survived. The time from disease onset to hospital admission (53.69 ± 38.14 vs 32.20 ± 20.75, P < 0.001) and to initial surgical treatment was longer in the “Step-up” than in the “One-step” group (54.38 ± 10.46 vs 76.58 ± 17.03, P < 0.001). Patients who underwent “Step-up” necrosectomy had a longer hospitalization duration (65.41 ± 28.14 vs 52.76 ± 24.71, P = 0.02), and more interventions (4.26 ± 1.71 vs 3.18 ± 1.39, P < 0.001). Postoperative inflammatory indicator levels were significantly lower than preoperative levels in each group. Although the incisional hernia incidence was higher in the “One-step” group, no significant difference was found in the composite outcomes of severe complications or death, new-onset organ failure, postoperative complications, inflammatory indicators, long-term complications, quality of life, and medical costs between the groups (P > 0.05).

CONCLUSION

Compared with the “Step-up” approach, the “One-step” approach is a safe and effective treatment method with better long-term quality of life and prognosis. It also provides an alternative surgical treatment strategy for patients with infected pancreatic necrosis.

Comparative outcomes of endoscopic ultrasound-guided lumen-apposing mental stents drainage for pancreatic pseudocysts and walled-off necrosis: Case series and meta-analysis

Background

Endoscopic ultrasound (EUS)-guided transmural drainage for pancreatic fluid collections (PFCs) has become the first-line treatment with quicker recovery and more minor injury compared with surgery and percutaneous drainage. The efficacy of stents implantation and drainage for different PFCs remains controversial, especially lumen-apposing metal stents (LAMS). This study aimed to compare the efficacy and safety of LAMS drainage for pancreatic pseudocysts (PPC) and walled-off necrosis (WON).

Methods

A meta-analysis was performed for LAMS drainage for WON and PPC by systematically searching PubMed, Cochrane, and Embase databases from January 2010 to January 2020. From 2017 to 2019, 12 patients who were treated with LAMS drainage for PFCs in our medical center were also reviewed and included in this study.

Results

Combining 11 copies of documents with the data from our medical center, a total of 585 patients with PFCs were enrolled in this meta-analysis, including 343 patients with WON and 242 with PPC. The technical success rate in WON is not significantly different from that of PPC (P = 0.08 > 0.05). The clinical success of LAMS placement was achieved in 99% vs 89% in PPC and WON, respectively (RR = 0.92, 95% CI: 0.86-0.98, P = 0.01 < 0.05). The further intervention of direct endoscopic necrosectomy was required by 60% of patients in WON group. There was no significant difference in the incidence of adverse events, including infection, bleeding, stent migration and stent occlusion, after LAMS placement between WON and PPC.

Conclusions

Endoscopic ultrasound-guided LAMS for PFCs are feasible, effective with preferable technical and clinical success rates. The clinical effect of LAMS on PPC is slightly better than that of WON, but its adverse reactions still need to be verified in a large-sample prospective study.

Outcomes of a single-step endoscopic ultrasound-guided drainage of pancreatic-fluid collections using an electrocautery-enhanced coaxial lumen-apposing, self-expanding metal stent with and without fluoroscopy

Background

Fluoroscopy is often used during the endoscopic drainage of pancreatic-fluid collections (PFCs). An electrocautery-enhanced coaxial lumen-apposing, self-expanding metal stent (ELAMS) facilitates a single-step procedure and may avoid the need for fluoroscopy. This study compares the treatment outcomes using ELAMS with and without fluoroscopy.

Methods

Patients with PFCs who had cystogastrostomy from January 2014 to February 2017 were enrolled. Two groups were studied based on fluoroscopy use. Technical success was defined as uneventful insertion of ELAMS at time of procedure. Clinical success was defined as (i) clinical resolution of symptoms after the procedure and (ii) >75% reduction in cyst size on computed tomography 8 weeks after stent placement. Adverse events including bleeding, stent migration, and infection were recorded.

Results

A total of 21 patients (13 males) had PFCs drainage with ELAMS in the study period. The mean age was 51.6 ± 14.2 years. Thirteen patients had walled-off necrosis while eight had a pancreatic pseudocyst. The mean size of the PFCs was 11.3 ± 3.3 cm. Fluoroscopy was used in seven cases (33%) and was associated with a longer procedure time compared to non-fluoroscopy (43.1 ± 10.4 vs 33.3 ± 10.5 min, P = 0.025). This association was independent of the size, location, or type of PFCs. Fluoroscopy had no effect on the technical success rates. In fluoroless procedures, the clinical resolution was 91% as compared to 71% in fluoroscopy procedures (P = 0.52) and the radiologic resolution was 57% as compared to 71% in fluoroscopy procedures (P = 0. 65). Three cases of stent migration/displacement occurred in the fluoroless procedures.

Conclusions

ELAMS may avoid the need for fluoroscopy during cystogastrostomy. Procedures without fluoroscopy were significantly shorter and fluoroscopy use had no impact on the technical or clinical success rates.

Safety and efficacy of lumen-apposing metal stents versus plastic stents to treat walled-off pancreatic necrosis: systematic review and meta-analysis

Background and study aims  Lumen-apposing metal stents (LAMS) are increasingly used for drainage of walled-off pancreatic necrosis (WON). Recent studies suggested greater adverse event (AE) rates with LAMS for WON. We conducted a systematic review and meta-analysis to compare the safety and efficacy of LAMS with double-pigtail plastic stents (DPPS) for endoscopic drainage of WON. The primary aim was to evaluate stent-related AEs. Methods  In October 2019, we searched the Ovid (Embase, MEDLINE, Cochrane) and Scopus databases for studies assessing a specific LAMS or DPPS for WON drainage conducted under EUS guidance. Safety outcomes were AE rates of bleeding, stent migration, perforation, and stent occlusion. Efficacy outcomes were WON resolution and number of procedures needed to achieve resolution. A subanalysis including non-EUS-guided cases was performed. Results  Thirty studies including one randomized controlled trial (total 1,524 patients) were analyzed. LAMS were associated with similar bleeding (2.5 % vs. 4.6 %, P =  0.39) and perforation risk (0.5 % vs. 1.1 %, P =  0.35) compared to DPPS. WON resolution (87.4 % vs. 87.5 %, P =  0.99), number of procedures to achieve resolution (2.09 vs. 1.88, P =  0.72), stent migration (5.9 % vs. 6.8 %, P =  0.79), and stent occlusion (3.8 % vs. 5.2 %, P =  0.78) were similar for both groups. Inclusion of non-EUS-guided cases led to significantly higher DPPS bleeding and perforation rates. Conclusions  LAMS and DPPS were associated with similar rates of AEs and WON resolution when limiting analysis to EUS-guided cases. Higher bleeding rates were seen in historical studies of DPPS without EUS guidance. Additional high-quality studies of WON treatment using consistent outcome definitions are needed.

Advancements in the endoscopic treatment of pancreatic fluid collections

Endoscopic drainage of pancreatic fluid collections (PFCs) with fewer complications and less trauma has gradually replaced surgery or percutaneous drainage to become the first-line treatment for PFCs. In recent years, the differential efficacy of various stent techniques to drain different types of PFCs has been controversial. This review summarizes the clinical applications of endoscopic ultrasound-guided stent placement for PFCs drainage.

Are Lumen-Apposing Metal Stents More Effective Than Plastic Stents for the Management of Pancreatic Fluid Collections: An Updated Systematic Review and Meta-analysis

Background and Aims

Recently, a new type of metal stent, named lumen-apposing metal stents (LAMS), has been designed to manage pancreatic fluid collections (PFC), and a few studies have reported its efficacy and safety. Therefore, we conducted this meta-analysis to investigate the role of LAMS for PFC.

Methods

We searched the studies from PubMed, MEDLINE, Embase, and Cochrane databases from inception to May 2019. We extracted the data and analyzed the technical success, clinical success, and adverse events of LAMS to evaluate its efficacy and safety.

Results

Twenty studies with 1534 patients were included. The pooled technical success, clinical success, and adverse event rates of LAMS for PFC were 96.2% (95% confidence interval (CI): 94.6%-97.4%), 86.8% (95% CI: 83.1%-89.8%), and 20.7% (95% CI: 16.1%-26.1%), respectively. Eight studies including 875 patients compared the clinical outcomes of LAMS with plastic stents. The pooled risk ratio (RR) of technical success and clinical success for LAMS and plastic stent was 1.01 (95% CI: 0.98-1.04, P = 0.62) and 1.06 (95% CI: 1.01-1.12, P = 0.03), respectively. As for the overall adverse events, the pooled RR was 1.51 (95% CI: 0.67-3.44, P = 0.32).

Conclusions

Our current study revealed that LAMS has advantages over plastic stents for PFC, with higher clinical success rate and lower complication rate of infection and occlusion.

Lumen-apposing metal stents in interventional endoscopy: a state-of-the-art review with focus on technical and clinical successes and complications

Endoscopic transmural drainage is considered the initial treatment option for pancreatic fluid collections. Recently, lumen-apposing metal stents have been introduced for pancreatic fluid collections drainage under endoscopic ultrasound guidance, in addition to evolving data in bile duct and gallbladder drainage. We aimed to perform systematic review with reporting pooled data analysis on technical success, clinical success and complications rate of endoscopic ultrasound-guided lumen-apposing metal stents uses. A MEDLINE/PubMed and EMBASE search for all studies on lumen-apposing metal stents uses in pancreatic, biliary and other indications was conducted. Data regarding safety, complications and yield were extracted and included in the final pooled analysis. Overall, 19 articles dealing with pancreatic fluid collections drainage, 18 articles reporting on bile duct drainage and 19 articles relevant to gallbladder drainage were identified. Technical and clinical successes in all disease conditions were high and reached more than 95%. Complications rate in pancreatic fluid collections, bile duct and gallbladder drainages were 12%, 11.2% and 9.8%, respectively. Endoscopic ultrasound-guided lumen-apposing metal stents is technically feasible with very high success rate and acceptable complications rate.

Lumen-apposing metal stents in management of pancreatic fluid collections: The nobody's land of removal timing

Pancreatic fluid collections (PFCs) develop as a result of damage to the major or peripheral pancreatic ducts, complication due to acute or chronic pancreatitis, trauma or iatrogenic causes. PFCs include pancreatic pseudocysts (PPs) and walled-off necrosis (WON). PFCs usually resolve spontaneously and are asymptomatic, but if they persist, increase in dimension or became symptomatics, therapeutic intervention is required. Available therapeutic interventions include surgical, percutaneous, and endoscopic drainage. The endoscopic approach is nowadays considered the first line-treatment of PFCs due to various advantages when compared with surgical or percutaneous drainage: decreased morbidity, length of hospital stay, and reduced costs. In the last few years, the endoscopic ultrasound (EUS)-guided transmural drainage, initially with plastic stents, gained popularity. More recently, fully covered self-expanding lumen-apposing metal stents (LAMS) have been demonstrated to be both, safe and effective with high clinical and technical success, reducing the risk of perforation, peritoneal leakage, migration and facilitating the drainage of necrotic contents. In the last few years, several studies evaluating the safety and efficacy of LAMS and their differences with plastic stents have been performed, but literature on the removal timing of this device and associated complications is still limited. The aim of this review is to analyze studies reporting information about the retrieval timing of LAMS and the related adverse events.

Endotherapy for pancreatic necrosis: An update

Approximately 20% of patients with acute pancreatitis develop pancreatic necrosis. The presence of necrosis in a pancreatic collection significantly worsens the prognosis. Pancreatic necrosis is associated with high mortality and morbidity. In the last few decades, there has been a significant revolution in the treatment of infected pancreatic necrosis. A step‐up approach has been proposed, from less invasive procedures to the operative intervention. Minimally invasive treatment modalities such as endoscopic drainage and necrosectomy, percutaneous drainage, and minimally invasive surgery have recently replaced open surgical necrosectomy as the first‐line treatment option. Endoscopic intervention for pancreatic necrosis is being increasingly performed with good success and a lower complication rate. However, techniques of endotherapy are still not uniform and vary as per local expertise, and there are still many unresolved questions with regard to the interventions in patients with pancreatic necrosis. The objective of this paper is to critically review the literature and update the concepts of endoscopic interventional therapy of pancreatic necrosis.

Retrievable puncture anchor traction method for EUS-guided gallbladder drainage: a porcine study

BACKGROUND AND AIMS

EUS-guided gallbladder drainage (EUS-GBD) is a challenging technique for endoscopists that requires a high level of skill. EUS-GBD is challenging because the gallbladder can be easily collapsed. To resolve this issue, we aimed to develop a retrievable puncture anchor traction (RPAT) method for EUS-GBD. We evaluated and compared the success rate, safety, and outcomes of the RPAT method for EUS-GBD against EUS-GBD without RPAT using a porcine model.

METHODS

In total, 16 Bama mini pigs (weighing 15-20 kg) were randomly divided into an experimental group (n = 8) and a control group (n = 8). The RPAT method was performed in the experimental group and EUS-GBD without retrievable puncture anchor was performed in the control group. Incidence of operative adverse events, wound healing, and success rates of EUS-GBD were compared and analyzed between the experimental group and the control group.

RESULTS

All EUS-GBD procedures were successfully performed in all 8 animals in the experimental group (100%). However, in the control group, EUS-GBD was successfully performed only on 4 pigs (50%); the remaining 4 pigs died because of EUS-GBD failure caused by gallbladder collapse leading to unsuccessful frontal stent release.

CONCLUSIONS

RPAT helped increase the success rate of EUS-GBD and could reduce gallbladder collapse. Therefore, we believe this method can be applied to EUS-GBD in the near future. Furthermore, RPAT will enhance the safety of EUS-GBD.

Interventional Endoscopic Ultrasonography in the Pancreas

Endoscopic ultrasonography (EUS) has enabled therapeutic endoscopists to intervene on conditions that have otherwise not been accessible with conventional endoscopy. Inflammatory fluid collections of the pancreas that may benefit from drainage are often not identifiable without EUS. Furthermore, EUS may improve the safety of transmural drainage by allowing for the identification of intervening blood vessels and reducing the need for fluoroscopy, and is complemented by new devices that simplify the access and stent delivery process. The use of EUS has also made the treatment of various pancreatic duct disorders possible when direct access is otherwise impossible.

Current uses and outcomes of lumen-apposing metal stents

The lumen-apposing metal stent (LAMS) is one of the revolutionary devices recently developed for gastrointestinal endoscopy. This device has a saddle-shaped design and large lumen. It was originally designed for drainage of transmural pancreatic fluid collection and in the last few years it has been used extensively for that indication. More recently, other in- and off-label indications have been proposed. Several types of LAMS are available, with or without an electrocautery-enhanced delivery system. In the current review we discuss the state of the art with regard to LAMS and their indications, usage, and outcomes.

Endoscopic ultrasound-guided drainage of pancreatic walled-off necrosis using self-expanding metal stents without fluoroscopy

AIM

To investigate whether endoscopic ultrasound (EUS)-guided insertion of fully covered self-expandable metal stents in walled-off pancreatic necrosis (WOPN) is feasible without fluoroscopy.

METHODS

Patients with symptomatic pancreatic WOPN undergoing EUS-guided transmural drainage using self-expandable and fully covered self expanding metal stents (FCSEMS) were included. The EUS visibility of each step involved in the transmural stent insertion was assessed by the operators as “visible” or “not visible”: (1) Access to the cyst by needle or cystotome; (2) insertion of a guide wire; (3) introducing of the diathermy and delivery system; (4) opening of the distal flange; and (5) slow withdrawal of the delivery system until contact of distal flange to cavity wall. Technical success was defined as correct positioning of the FCSEMS without the need of fluoroscopy.

RESULTS

In total, 27 consecutive patients with symptomatic WOPN referred for EUS-guided drainage were included. In 2 patients large traversing arteries within the cavity were detected by color Doppler, therefore the insertion of FCSEMS was not attempted. In all other patients (92.6%) EUS-guided transgastric stent insertion was technically successful without fluoroscopy. All steps of the procedure could be clearly visualized by EUS. Nine patients required endoscopic necrosectomy through the FCSEMS. Adverse events were two readmissions with fever and one self-limiting bleeding; there was no procedure-related mortality.

CONCLUSION

The good endosonographic visibility of the FCSEMS delivery system throughout the procedure allows safe EUS-guided insertion without fluoroscopy making it available as bedside intervention for critically ill patients.

Management of Inflammatory Fluid Collections and Walled-Off Pancreatic Necrosis

OPINION STATEMENT

Pancreatic fluid collections are a frequent complication of acute pancreatitis. The revised Atlanta criterion classifies chronic fluid collections into pseudocysts and walled-off pancreatic necrosis (WON). Symptomatic PFCs require drainage options that include surgical, percutaneous, or endoscopic approaches. With the advent of newer and more advanced endoscopic tools and expertise, minimally invasive endoscopic drainage has now become the preferred approach. An endoscopic ultrasonography (EUS)-guided approach for pancreatic fluid collection drainage is now the preferred endoscopic approach. Both plastic stents and metal stents are efficacious and safe; however, metal stents may offer an advantage, especially in infected pseudocysts and in WON. Direct endoscopic necrosectomy is often required in WON. Lumen apposing metal stents allow for direct endoscopic necrosectomy and debridement through the stent lumen and are now preferred in these patients. Endoscopic retrograde cholangiopancreatography with pancreatic duct exploration should be performed concurrent to PFC drainage in patients with suspected PD disruption. PD disruption is associated with an increased severity of pancreatitis, an increased risk of recurrent attacks of pancreatitis and long-term complications, and a decreased rate of PFC resolution after drainage. Ideally, pancreatic ductal disruption should be bridged with endoscopic stenting.