Endoscopic intestinal bypass creation by using self-assembling magnets in a porcine model

Magnetic compression anastomosis gastrojejunostomy: feasibility and efficacy of a novel device in a swine model

BACKGROUND

Means of addressing technical challenges in forming gastrojejunostomy (GJ) anastomoses and maintaining their patency are sought.

OBJECTIVES

Evaluation of preclinical feasibility and healing efficacy of a novel linear magnetic compression anastomosis (MCA) device to form a patent GJ versus sutured jejunal enterotomy (JE) sites in swine.

SETTING

Single-center veterinary testing facility.

METHODS

Feasibility of 3 prototype sizes (4, 6, and 8 cm) of a metal MCA device (MCAD) to form a patent GJ was evaluated over 6 weeks. A distal magnet was laparoscopically inserted in the jejunum, a proximal magnet was placed gastroscopically in the stomach; magnets were aligned to gradually form an anastomosis, self-detached, and be expelled. At necropsy, MCAs were assessed for patency and compared with JE tissues to evaluate wound healing.

RESULTS

MCADs aligned at the GJ location without complications. In 5/6 MCAD pairs, dislodgement occurred between 7 and 26 days; expulsion 13-31 days; 1 MCAD pair was retained in the stomach. At necropsy, all pigs were healthy, gaining a mean 15.0 kg. Anastomoses were not adequately patent in 2/4 pigs receiving the 4-cm or 6-cm MCADs because their linear length was too small. But, anastomoses of both pigs receiving the 8-cm MCADs maintained full patency. Minimal inflammation and fibrosis were seen in MCA specimens versus sutured enterotomies.

CONCLUSIONS

A novel linear MCA device was feasible and effectively created a patent GJ anastomosis in swine with minimal inflammation and fibrosis. The MCAD may be appropriate for clinical evaluation.

Spanish Experience with Latero-Lateral Duodeno-Ileostomy + Sleeve Gastrectomy with Magnet Anastomosis System

BACKGROUND

The partial diversion of intestinal contents facilitates achieving and maintaining weight loss and improving glycemic control in patients with obesity and with or without T2DM. The purpose of this study is to report our experience and 1-year follow-up with novel modification of SADI-S.

METHODS

This study is a part of a multicentric trial of patients that underwent primary side-to-side duodeno-ileostomy and sleeve gastrectomy (SG) with GT metabolic solutions magnetic anastomosis system. Feasibility, safety, and initial efficacy were evaluated.

RESULTS

The mean age of the patients included was 48 ± 8.75 years and the preoperative BMI was 43.32 ± 2.82 kg/m2. The complications were present in 30% of patients. The anastomosis patency was confirmed by the passage of radiological contrast under fluoroscopy at a mean of 17 days (17-29 days), and the mean expulsion time was 42 days (32-62). The mean diameter of the anastomosis after the magnet expulsion was 13.8 × 11.4 mm. The percentage of total weight lost at 1 year was 38.68 ± 8.48% (p < 0.001). The percentage of excess weight loss 82.5 ± 18.44% (p < 0.001) and improvements in glucose profiles were observed. Mean baseline HbA1c 5.77 ± 0.31% was reduced to 5.31 ± 0.26% (p < 0.024).

CONCLUSIONS

Latero-lateral duodeno-ileostomy + SG with magnetic duodenal bipartition is afeasible and reasonably safe technique and induces weight loss in patients with obesity and improvement of glycemic control. This modification could be considered as an option to standard SADI-S or as a first step in two stages procedure. However, larger studies are needed.

TRIAL REGISTRATION

Clinicaltrials.gov Identifier: #NCT05322122.

Update on Endoscopic Treatments for Obesity

PURPOSE OF REVIEW

Increased morbidity seen with rising obesity rates continues to place an unheralded burden on our health system. Lack of higher bariatric surgery utilization and limitations with lifestyle modification and pharmacotherapy highlights the need for additional therapies for obesity. Endoscopic bariatric and metabolic therapies (EBMT) are effective, safe treatments for obesity. Current FDA-approved EBMT are confined to gastric modalities while small bowel directed therapies are still considered investigational. This review highlights current modalities of EBMT.

RECENT FINDINGS

Many randomized controlled trials have been performed, including both open label and sham-controlled, which have demonstrated safety and efficacy of EBMT over lifestyle therapy alone. In addition, emerging evidence from clinical experience further supports EBMT for treatment of obesity. Current evidence supports the safety and efficacy of EBMT for obesity treatment in conjunction with lifestyle therapy. They can also be used concurrently with weight loss medications to increase total weight loss.

Feasibility experiment of a novel deformable self-assembled magnetic anastomosis ring (DSAMAR) for gastrointestinal anastomosis through a natural orifice

Although the application of magnetic compression anastomosis is becoming increasingly widespread, the magnets used in earlier studies were mostly in the shape of a whole ring. Hence, a deformable self-assembled magnetic anastomosis ring (DSAMAR) was designed in this study for gastrointestinal anastomosis. Furthermore, its feasibility was studied using a beagle model. The designed DSAMAR comprised 10 trapezoidal magnetic units. Twelve beagles were used as animal models, and DSAMARs were inserted into the stomach and colon through the mouth and anus, respectively, via endoscopy to achieve gastrocolic magnamosis. Surgical time, number of failed deformations, survival rate of the animals, and the time of magnet discharge were documented. A month later, specimens of the anastomosis were obtained and observed with the naked eye as well as microscopically. In the gastrocolic anastomosis of the 12 beagles, the procedure took 65-120 min. Although a deformation failure occurred during the operation in one of the beagles, it was successful after repositioning. The anastomosis was formed after the magnet fell off 12-18 days after the operation. Naked eye and microscopic observations revealed that the anastomotic specimens obtained 1 month later were well-formed, smooth, and flat. DSAMAR is thus feasible for gastrointestinal anastomosis under full endoscopy via the natural orifice.

Endoscopic gastrointestinal bypass anastomosis using deformable self-assembled magnetic anastomosis rings (DSAMARs) in a pig model

BACKGROUND

To investigate the feasibility of a deformable self-assembled magnetic anastomosis ring (DSAMAR), designed and developed by us, for endoscopic gastrointestinal bypass anastomosis.

METHODS

Ten experimental pigs were used as model animals. The DSAMAR comprises 10 trapezoidal magnetic units, arranged in a straight line under the constraint of a guide wire. When the desired anastomosis site is reached under the guidance of an endoscope, the catheter pushes the magnetic unit along the guide wire. The linear DSAMAR can be assembled into a circular DSAMAR. Two DSAMARs were inserted, one at the end of the duodenum and the other into the stomach successively. They attracted each other and compressed the wall of the stomach and duodenum to establish gastrointestinal bypass anastomosis. The experimental pigs were euthanized 4 weeks after the operation, and the gastrointestinal bypass anastomosis specimens were obtained. The anastomosis formation was evaluated by the naked eye and histology.

RESULTS

Gastrointestinal bypass anastomosis with DSAMARs was successfully performed. The average operation time under an endoscope was 70.30 ± 19.05 min (range: 43-95 min). The DSAMARs were discharged through the anus 10-17 days after surgery. There were no complications such as gastrointestinal bleeding, perforation, anastomotic fistula, and gastrointestinal obstruction during and after the operation. Gastroscopy and gross specimen of the anastomosis showed a well-formed magnetic anastomosis. Histological observation showed good continuity of the serous membrane and the mucosa of magnetic anastomosis.

CONCLUSION

The DSAMAR is a safe and feasible device for fashioning gastrointestinal bypass anastomosis in this animal model.

Small intestine-targeted endoscopic bariatrics: Current status and future perspectives

The global obesity epidemic shows no signs of slowing down. Endoscopic bariatric and metabolic therapies (EBMTs) are being increasingly adopted as treatment options for obesity and obesity-related comorbidities, due to their minimally invasive nature and ease of delivery. According to the site of action along the gastrointestinal tract, EBMTs can be divided into two categories: gastric EBMTs, and small intestine-targeted EBMTs. Unlike gastric EBMTs, which work through a volume-restricting mechanism leading to early satiety and reduced caloric intake, small intestine-targeted EBMTs can be metabolically beneficial through foregut and/or hindgut pathways independent of weight loss, and therefore have great potential for the treatment of obesity-related metabolic comorbidities such as type 2 diabetes. Although none of the small intestine-targeted EBMTs have been approved by the US Food and Drug Administration to date, their clinical efficacy and safety have been extensively explored in investigational trials. This review aims to summarize and provide a comprehensive understanding of small intestine-targeted EBMTs in clinical and preclinical settings, and to further discuss their potential mechanisms of action.

First-in-Human Side-to-Side Magnetic Compression Duodeno-ileostomy with the Magnet Anastomosis System

PURPOSES

Classical gastrointestinal anastomoses are formed with sutures and/or metal staples, resulting in significant bleeding and leak rates. This study evaluated the feasibility and safety of the novel magnet anastomosis system (MS) to create a side-to-side duodeno-ileal (DI) diversion for weight loss and type 2 diabetes (T2D) resolution.

MATERIALS AND METHODS

Patients with severe obesity (body mass index (BMI) ≥ 35 kg/m2 with/without T2D (HbA1C ≥ 6.5%)) underwent the study procedure, a side-to-side MS DI diversion, with a standard sleeve gastrectomy (SG). A linear magnet was delivered by flexible endoscopy to a point 250 cm proximal to the ileocecal valve; a second magnet was positioned in the first part of the duodenum; the bowel segments containing magnets were apposed, initiating gradual anastomosis formation. Laparoscopic assistance was used to obtain bowel measurements, obviate tissue interposition, and close mesenteric defects.

RESULTS

Between November 22 and 26, 2021, 5 female patients (mean weight 117.6 ± 7.1 kg, BMI (kg/m2) 44.4 ± 2.2) underwent side-to-side MS DI + SG. All magnets were successfully placed, expelled without re-intervention, and formed patent durable anastomoses. Total weight loss at 12 months was 34.0 ± 1.4% (SEM); excess weight loss, 80.2 ± 6.6%; and BMI reduction, 15.1. Mean HbA1C (%) dropped from 6.8 ± 0.8 to 4.8 ± 0.2; and glucose (mg/dL), from 134.3 ± 17.9 to 87.3 ± 6.3 (mean reduction, 47.0 mg/dL). There was no anastomotic bleeding, leakage, obstruction, or infection and no mortality.

CONCLUSIONS

Creation of a side-to-side magnetic compression anastomosis to achieve duodeno-ileostomy diversion in adults with severe obesity was feasible and safe, achieved excellent weight loss, and resolved type 2 diabetes at 1-year follow-up.

TRIAL REGISTRATION

Clinicaltrials.gov Identifier: NCT05322122.

Advances in endobariatrics: past, present, and future

The obesity epidemic in the USA and worldwide is well documented and continues to grow. Endoscopic metabolic and bariatric therapies may offer a less invasive approach than surgical intervention. This article will review advances in endobariatrics over the last several decades, addressing the past and current state of bariatric and metabolic endoscopy. Food and Drug Administration-cleared devices and interventions currently under investigation are described including gastric devices, gastric remodeling procedures, small-bowel devices, duodenal ablation, as well as procedures to address weight regain after bariatric surgery. Future studies evaluating gastric and duodenal combination therapy, adjunctive pharmacotherapy, as well as individualized precision-health algorithms are underway.

Side-to-side duodeno-ileal magnetic compression anastomosis: design and feasibility of a novel device in a porcine model

BACKGROUND

Minimally invasive metabolic/bariatric surgery (MBS) may be further advanced by magnetic compression anastomosis (MCA) technology. The study aimed to develop a magnet sized to create a patent duodeno-ileostomy (DI) and verify its effectiveness in a porcine model.

METHODS

Developmental study phase: magnets with 4 different flange-offset dimensions were tested to identify a design that would successfully form a compression anastomosis. Verification phase: evaluation of the selected design's efficacy. In each 6-week phase (4 pigs/phase), one magnet was inserted laparoscopically in the jejunum, one placed gastroscopically in the duodenum. Magnets were aligned, gradually fused, formed an anastomosis, and then detached and were expelled. At necropsy, MCA sites and sutured enterotomy sites were collected and compared.

RESULTS

Developmental phase: the linear BC42 magnet with a 2.3-mm flange offset design was selected. Verification phase: in 4 swine magnets were mated at the target location, confirmed radiographically. Mean time to magnet detachment 16.0 days (12-22), to expulsion 24.5 days (17-33). MCA was achieved in all animals at time of sacrifice. Animals gained a mean 9.5 kg (3.9-11.8). Specimens revealed patent anastomoses of ≥ 20 mm with smooth mucosa and minimal inflammation and fibrosis compared to sutured enterotomies. One pig underwent corrective surgery for a mesenteric hernia without sequelae.

CONCLUSION

In a large-animal model, gross and histopathologic examination confirmed that the linear MCA device created a patent, well-vascularized, duodeno-ileal anastomosis. The novel MCA device may be appropriate for use in human MBS procedures.

The Evolving Use of Magnets in Surgery: Biomedical Considerations and a Review of Their Current Applications

The novel use of magnetic force to optimize modern surgical techniques originated in the 1970s. Since then, magnets have been utilized as an adjunct or alternative to a wide array of existing surgical procedures, ranging from gastrointestinal to vascular surgery. As the use of magnets in surgery continues to grow, the body of knowledge on magnetic surgical devices from preclinical development to clinical implementation has expanded significantly; however, the current magnetic surgical devices can be organized based on their core function: serving as a guidance system, creating a new connection, recreating a physiologic function, or utilization of an internal–external paired magnet system. The purpose of this article is to discuss the biomedical considerations during magnetic device development and review the current surgical applications of magnetic devices.

A Gut-Centric Model of Metabolic Homeostasis

Modern changes in diet and lifestyle have led to an explosion of insulin resistance and metabolic diseases around the globe which, if left unchecked, will become a principal driver of morbidity and mortality in the 21st century. The nature of the metabolic homeostatic shift within the body has therefore become a topic of considerable interest. While the gut has long been recognized as an acute nutrient sensor with signaling mechanisms to the other metabolic organs of the body, its role in regulating the body's metabolic status over longer periods of time has been underappreciated. Recent insights from bariatric surgery and intestinal nutrient stimulation experiments provide a window into the adaptive role of the intestinal mucosa in a foregut/hindgut metabolic balance model that helps to define metabolic parameters within the body-informing the metabolic regulation of insulin resistance versus sensitivity, hunger versus satiety, energy utilization versus energy storage, and protection from hypoglycemia versus protection from hyperglycemia. This intestinal metabolic balance model provides an intellectual framework with which to understand the distinct roles of proximal and distal intestinal segments in metabolic regulation. The model may also aid in the development of novel disease-modifying therapies that can correct the dysregulated metabolic signals from the intestine and stem the tide of metabolic diseases in society.

Systematic Review and Meta-Analysis on Colorectal Anastomotic Techniques

Purpose

Anastomosis creation after resective gastrointestinal surgery is a crucial task. The present review examines the techniques and implants currently available for anastomosis creation and analyses to which extent they already address our clinical needs, with a special focus on their potential to enable further trauma minimization in visceral surgery.

Methods

A multi-database research was conducted in MEDLINE, Scopus, and Cochrane Library. Comparative controlled and uncontrolled clinical trials dealing with anastomosis creation techniques in the intestinal tract in both German and English were included and statistically significant differences in postoperative complication incidences were assessed using the RevMan5.4 Review Manager (Cochrane Collaboration, Oxford, UK).

Results

All methods and implant types were analyzed and compared with respect to four dimensions, assessing the techniques' current performances and further potentials for surgical trauma reduction. Postoperative outcome measures, such as leakage, stenosis, reoperation and mortality rates, as well as the tendency to cause bleeding, wound infections, abscesses, anastomotic hemorrhages, pulmonary embolisms, and fistulas were assessed, revealing the only statistically significant superiority of hand-suture over stapling anastomoses with respect to the occurrence of obstructions.

Conclusion

Based on the overall complication rates, it is concluded that none of the anastomosis systems addresses the demands of operative trauma minimization sufficiently yet. Major problems are furthermore either low standardization potentials due to dependence on the surgeons' levels of experience, high force application requirements for the actual anastomosis creation, or large and rigid device designs interfering with flexibility demands and size restrictions of the body's natural access routes. There is still a need for innovative technologies, especially with regard to enabling incisionless interventions.

Lumen Apposition: A Changing Landscape in Therapeutic Endoscopy

The concept of endoscopic lumen apposition has seen a dramatic shift in the last several decades. Early natural orifice trans-luminal endoscopic surgery (NOTES) concepts have transformed into specialized lumen-apposing metal stents (LAMSs) and delivery devices, which provide endoscopists a minimally invasive alternative to surgical intervention. These LAMSs have become the bedrock of therapeutic endoscopy and provide treatment for a wide spectrum of gastrointestinal disorders. In this review, we summarize the changing landscape of therapeutic endoscopy by highlighting the use of LAMS and future directions as well as alternative devices to achieve lumen apposition.

Lumen Apposition: A Changing Landscape in Therapeutic Endoscopy

The concept of endoscopic lumen apposition has seen a dramatic shift in the last several decades. Early natural orifice trans-luminal endoscopic surgery (NOTES) concepts have transformed into specialized lumen-apposing metal stents (LAMSs) and delivery devices, which provide endoscopists a minimally invasive alternative to surgical intervention. These LAMSs have become the bedrock of therapeutic endoscopy and provide treatment for a wide spectrum of gastrointestinal disorders. In this review, we summarize the changing landscape of therapeutic endoscopy by highlighting the use of LAMS and future directions as well as alternative devices to achieve lumen apposition.

Endoscopic Procedures for Weight Loss

PURPOSE OF REVIEW

To provide updated evidence on the endoscopic procedures for weight loss and to bring personal insights on the future of endobariatrics.

RECENT FINDINGS

Intragastric balloons promote significant improvement in histologic and radiologic aspects of non-alcoholic steatohepatitis; the endoscopic sleeve gastroplasty is effective up to 5 years and seems particularly beneficial to patients with BMI≤40kg/m²; distal POSE is a promising technique but still lacks adequate clinical data; aspiration therapy triggers remarkable weight loss, but data on weight trends after removal of the device are still lacking; the satiety-inducing device, the sleeveballoon, the gastric mucosal devitalization, and the endoscopic magnetic partial jejunal diversion are promising procedures still under study and refinements. Several therapeutic options are necessary during obesity's natural history. Therefore, endobariatrics should act in harmony with lifestyle interventions, diet modification, psychological treatment, pharmacotherapy, and bariatric surgery seeking the best outcome in the long term.

Sutureless Duodeno-Ileal Anastomosis with Self-Assembling Magnets: Safety and Feasibility of a Novel Metabolic Procedure

BACKGROUND

Less invasive and safer anastomotic techniques are desirable. We aimed to determine technical feasibility and safety of sutureless duodeno-ileal side-to-side anastomosis in obese patients using self-assembling magnets.

METHODS

This was an open-label, prospective, and single-arm study including obese patients (BMI 30-50 kg/m²) with type II diabetes. The ileal magnet was deployed laparoscopically, and the duodenal magnet was deployed endoscopically. Both magnets were coupled under laparoscopic and fluoroscopic guidance. The primary endpoints were technical feasibility and safety. The secondary endpoints were patency of the anastomosis, HbA1c reduction, and weight loss 12 months after the procedure.

RESULTS

A total of 8 patients were enrolled in the study; median age was 51.5 years (range: 34-65), and median BMI was 38.8 kg/m² (range: 35-47.9). The mean procedural duration was 63.5 min (range: 41-95). No intraoperative complications were recorded, and no major postoperative morbidity related to the procedure occurred. Magnets were expelled at a median of 29.5 days after the procedure with no associated complications. Upper endoscopy at 12 months confirmed patent anastomoses with healthy-appearing mucosa in all patients. HbA1c reduced below 7.0% in 6 out of 8 (75%) patients, and greater than 5% of total body weight loss was observed in 7 out of 8 (87.5%) patients at 12 months.

CONCLUSIONS

Sutureless duodeno-ileal side-to-side anastomosis using self-assembling magnets is feasible and safe in obese patients, and a dual-path enteral diversion with large-caliber and durable anastomosis can be achieved.

The current state of bariatric endoscopy

A variety of endoscopic bariatric and metabolic treatments (EBMTs) have been developed in recent years to combat the growing prevalence of obesity in the United States (US) and worldwide. This manuscript reviews the current state of bariatric endoscopy, detailing all US Food and Drug Administration (FDA) approved EBMTs including space-occupying intragastric balloons (IGBs), aspiration therapy, and endoscopic tissue apposition devices. Additionally, this review describes non-FDA approved treatments including additional IGBs, endoluminal bypass liners, duodenal mucosal resurfacing, and endoscopically placed anastomosis devices.

Endobariatrics and Metabolic Endoscopy: Can We Solve the Obesity Epidemic with Our Scope?

PURPOSE OF REVIEW

Obesity is a chronic relapsing disease that results in cardiovascular disease, diabetes mellitus, and non-alcoholic fatty liver disease. Currently, surgery represents the most effective treatment. However, the advent of minimally invasive endoscopic bariatric therapy (EBT) has shifted the treatment paradigm to less invasive, cost-effective procedures with minimal complications and recovery time that are preferred by patients. In this review, we will describe current and future EBTs, focusing on outcomes and safety.

RECENT FINDINGS

The endoscope has provided an incisionless portal into the gastrointestinal tract for placement of space-occupying devices and intraluminal procedures. EBTs are no longer solely manipulating anatomic alterations; instead, they aim to improve metabolic parameters such as glycated hemoglobin, low-density lipoprotein, cholesterol, and hepatic indices by targeting the mucosal layer of the gastrointestinal tract. The endoscope has succeeded in facilitating clinically meaningful weight loss and improvement of metabolic parameters. Future, solutions to the obesity epidemic will likely entail genetic testing, evaluation of the microbiome, and delivery of personalized therapy, utilizing combination endoscopic modalities that change the anatomy and physiology of individual patients, with new targets such as the abnormal metabolic signal.

Bariatric and Metabolic Therapies Targeting the Small Intestine

The global prevalence of obesity and type 2 diabetes (T2DM) necessitates an increased reliance on effective and safe endoscopic therapies. While surgery is highly effective, endoscopic therapies may be able to reach a greater number of affected individuals and help to reduce the burden of disease worldwide. Although current endoscopic treatments entail space occupying gastric devices as well as suturing or plication, innovative, non-Food and Drug Administration (FDA) approved small bowel specific endoscopic bariatric and metabolic therapies have been developed within the last several years. Small intestine therapies include endoluminal bypass liners, duodenal mucosal resurfacing, endoscopic anastomosis systems, and restricted duodenal flow treatments. These endoscopic bariatric and metabolic therapies rely upon foregut and hindgut mechanisms to achieve weight loss and improve glucose homeostasis. This review will detail these important small bowel mechanisms and evaluates current small bowel endoscopic treatments.

Endoscopic applications of magnets for the treatment of gastrointestinal diseases

Endoscopic treatment of gastrointestinal diseases has developed rapidly in recent years, due to its minimally invasive nature. One of the main contributing factors for this progress is the improvement of endoscopic instruments, which are essential for facilitating safe and effective endoscopic interventions. However, the slow learning curve required in the implementation of many advanced endoscopic procedures using standard devices is associated with a high risk of complications. Other routine procedures may also be complicated by unexpected difficulties. Based on the ferromagnetic properties of many objects, both internal and external magnetic devices have been developed and applied for multiple endoscopic interventions. The applications of magnets, mainly including compression, anchoring and traction, facilitate many difficult procedures and make it feasible to operate procedures that were previously impossible. Other novel endoscopic applications, such as magnetic nanoparticles, are also under development. In this article, we reviewed published studies of endoscopic applications of magnets for the treatment of gastrointestinal diseases such as precancerous lesions and cancer, obstruction, stricture, congenital and acquired malformations, motility disorders, and ingestion of foreign bodies. Since several endoscopic applications of magnets may also be relevant to surgery, we included them in this review.

Magnetic cholecysto-duodenal anastomosis

INTRODUCTION

There is a growing interest in minimally invasive endoscopic gallbladder drainage therapies. Unlike stenting, a technology based on magnetic compression could theoretically produce a durable drainage anastomosis without residual foreign material. This study aimed to evaluate the safety and technical feasibility of a cholecysto-duodenal magnetic compression anastomosis.

MATERIAL AND METHODS

We performed a survival study of two Yorkshire pigs. Duodenal magnets were deployed endoscopically; reciprocal gallbladder magnets were placed laparoscopically, and the magnets were coupled. Pigs underwent serial endoscopy documenting magnet expulsion and evolution of cholecysto-duodenal anastomosis creation. Necropsies and histological evaluation were performed. Primary endpoints were technical success and safety. Secondary endpoints included anastomosis integrity, patency, and histologic characteristics.

RESULTS

Magnets were successfully delivered and coupled. Patent, leak-free anastomoses formed by day 4. Magnets were expelled by day 10. All anastomoses were widely patent at one month (mean diameter 15 mm). Necropsy showed the absence of adhesions affecting the anastomosis. Histology showed complete re-epithelialization without inflammation or foreign body reaction.

CONCLUSIONS

Magnetic cholecysto-duodenal anastomosis for gallbladder drainage appears safe and feasible in the animal model. The anastomoses are patent, leak-free, and without inflammation from the presence of foreign material. Technical modifications for magnet delivery under endoscopic ultrasound (EUS) guidance are currently underway.

Endoscopic techniques for weight loss and treating metabolic syndrome

PURPOSE OF REVIEW

The endoscopic armamentarium against obesity and metabolic syndrome is rapidly growing and improving. Novel devices have been tested and recent data either support or reject their use. We aim to discuss current data on new endoscopic procedures addressing overweight, diabetes, and metabolic syndrome.

RECENT FINDINGS

Four-year follow-up of the aspiration therapy have shown efficacy and safety at long term. A recent consensus on intragastric balloon gathered experience from more than 40 000 procedures and standardized most steps of the treatment. The TransPyloric Shuttle has been proven effective at short term but carries high rates of adverse events. The endoscopic sleeve gastroplasty promotes similar weight loss to laparoscopic sleeve gastrectomy in mildly obese patien. The endoluminal magnetic partial jejunal diversion promoted good weight loss and a significant reduction in glycated hemoglobin (HbA1c) but most cases required laparoscopic assistance to couple the magnets. One-year follow-up demonstrated that the duodenal mucosal resurfacing carried a 1.0% reduction in HbA1c.

SUMMARY

Innovative endoscopic procedures focused on the treatment of overweight and related diseases are available and there is growing evidence supporting their use. Nonetheless, a multidisciplinary approach is mandatory. VIDEO ABSTRACT: http://links.lww.com/COG/A25.

Evolution of Endoscopic Bariatric Devices: From Development to Practice

OBJECTIVES

To familiarize medical providers with the Food and Drug Administration approval process for antiobesity devices and to provide a brief overview of current and promising endoscopy-based bariatric devices.

METHODS

Literature review of published scholarly articles.

RESULTS

There has been a rapid development of novel endoscopic bariatric therapies in recent years, resulting in the approval of multiple devices. Several promising endoscopic strategies are currently under investigation and review. The Food and Drug Administration has laid down an objective-tiered model to review antiobesity device applications.

DISCUSSION

Endoscopic bariatric devices provide a new and promising paradigm in obesity management both as first-line therapy and as adjunctive treatment to medical and surgical strategies. Physicians who plan to offer endoscopic bariatric therapy in their practice need appropriate understanding of the regulatory processes involved in the development and approval of such devices.

Use of magnets in gastrointestinal surgery

BACKGROUND

Laparoscopic and endoscopic surgery has undergone vast progress during the last 2 decades, translating into improved patient outcomes. A prime example of this development is the use of magnetic devices in gastrointestinal surgery. Magnetic devices have been developed and implemented for both laparoscopic and endoscopic surgery, providing alternatives for retraction, anchoring, and compression among other critical surgical steps. The purpose of this review is to explore the use of magnetic devices in gastrointestinal surgery, and describe different magnetic technologies, current applications, and future directions.

METHODS

IRB approval and written consent were not required. In this review of the existing literature, we offer a critical examination at the use of magnets for gastrointestinal surgery currently described. We show the experiences done to date, the benefits in laparoscopic and endoscopic surgery, and additional future implications.

RESULTS

Magnetic devices have been tested in the field of gastrointestinal surgery, both in the contexts of animal and human experimentation. Magnets have been mainly used for retraction, anchoring, mobilization, and anastomosis.

CONCLUSION

Research into the use of magnets in gastrointestinal surgery offers promising results. The integration of these technologies in minimally invasive surgery provides benefits in various procedures. However, more research is needed to continually evaluate their impact and implementation into surgical practice.

Gastric mucosal devitalization is safe and effective in reducing body weight and visceral adiposity in a porcine model

BACKGROUND AND AIMS

The early improvement in metabolic profile after sleeve gastrectomy (SG) indicates that the significant benefits of metabolic surgery are gastric in origin. We have previously demonstrated that devitalization of the gastric mucosa (without a reduction in gastric volume) in metabolically disturbed obese rats results in an improvement of obesity and its associated comorbidities. The aims of this study were to assess the technical feasibility, efficacy, and safety of gastric mucosal devitalization (GMD) in a large animal (porcine) model.

METHODS

A 3-arm (GMD versus SG versus sham [SH]) prospective randomized controlled trial with an 8-week follow-up period was performed. The primary endpoint was relative weight loss. Secondary endpoints were absolute body weight, abdominal visceral adiposity, abdominal subcutaneous adiposity, organ lipid content, and serum ghrelin level.

RESULTS

GMD resulted in a significant relative weight loss of 36% over SH at 8 weeks (P < .05). There was no significant difference in relative weight loss between GMD and SG at 4 weeks; however, SG resulted in a 29% superior relative weight loss at 8 weeks (P < .05). With regard to visceral adiposity, there was a significant benefit of GMD over SH at 8 weeks. Despite differences in relative weight loss, there was no significant difference in visceral adiposity between SG and GMD at 8 weeks. Significant improvements in GMD over SH were noted with regard to skeletal and heart muscle lipid content. GMD pigs at 8 weeks demonstrated regeneration of the gastric mucosa without ulceration or significant scarring. Despite mucosal regeneration, the abundance of serum ghrelin was significantly lower in the GMD cohort compared with the SG and SH cohorts.

CONCLUSIONS

GMD was technically feasible and resulted in relative weight loss and an improvement in visceral adiposity. The benefits noted were out of proportion to what would be expected with weight loss alone.

Gut as an emerging organ for the treatment of diabetes: focus on mechanism of action of bariatric and endoscopic interventions

Increasing worldwide prevalence of type 2 diabetes mellitus and its accompanying pathologies such as obesity, arterial hypertension and dyslipidemia represents one of the most important challenges of current medicine. Despite intensive efforts, high percentage of patients with type 2 diabetes does not achieve treatment goals and struggle with increasing body weight and poor glucose control. While novel classes of antidiabetic medications such as incretin-based therapies and gliflozins have some favorable characteristics compared to older antidiabetics, the only therapeutic option shown to substantially modify the progression of diabetes or to achieve its remission is bariatric surgery. Its efficacy in the treatment of diabetes is well established, but the exact underlying modes of action are still only partially described. They include restriction of food amount, enhanced passage of chymus into distal part of small intestine with subsequent modification of gastrointestinal hormones and bile acids secretion, neural mechanisms, changes in gut microbiota and many other possible mechanisms underscoring the importance of the gut in the regulation of glucose metabolism. In addition to bariatric surgery, less-invasive endoscopic methods based on the principles of bariatric surgery were introduced and showed promising results. This review highlights the role of the intestine in the regulation of glucose homeostasis focusing on the mechanisms of action of bariatric and especially endoscopic methods of the treatment of diabetes. A better understanding of these mechanisms may lead to less invasive endoscopic treatments of diabetes and obesity that may complement and widen current therapeutic options.

Partial jejunal diversion using an incisionless magnetic anastomosis system: 1-year interim results in patients with obesity and diabetes

BACKGROUND AND AIMS

Most patients with type 2 diabetes mellitus have obesity. Studies show that bariatric surgery is superior to medical treatment for remission of type 2 diabetes mellitus. Nevertheless, very few patients undergo surgery, and a less-invasive endoscopic alternative is desirable.

METHODS

This was a single-arm first-in-human pilot study designed to evaluate the technical feasibility, safety, and clinical performance of the incisionless magnetic anastomosis system (IMAS) to create a partial jejunal diversion (PJD). Ten patients with obesity and type 2 diabetes mellitus, prediabetes, or no diabetes were enrolled. A PJD to the ileum was attempted in all patients under general anesthesia. The IMAS was delivered through the working channel of a colonoscope, with laparoscopic supervision. The patients were not required to participate in an intensive lifestyle/diet management program. Endoscopic visualization of the anastomosis was obtained at 2, 6, and 12 months. Patient weight, glycemic profile, and metabolic panels were acquired at 0.5, 1, 2, 3, 6, 9, and 12 months.

RESULTS

A PJD was created in all patients with no device-related serious adverse events. The anastomosis remained widely patent in all patients at 1 year. Average total weight loss was 14.6% (40.2% excess weight loss at 12 months). A significant reduction in glycated hemoglobin level was observed in all diabetic (1.9%) and prediabetic (1.0%) patients, while reducing or eliminating the use of diabetes medications.

CONCLUSIONS

Permanent anastomosis for PJD was created in all patients with the IMAS. This resulted in improvement in measures of hyperglycemia and progressive weight loss. (Clinical trial registration number: NCT02839512.).

Endoscopic Ultrasound-Guided Gastrojejunostomy

Gastric outlet obstruction is a common complication of advanced upper gastrointestinal and pancreatic malignancies. Endoscopic ultrasound (EUS)-guided gastrojejunostomy is a new option that may provide a more durable solution than enteral stenting with shorter recovery time and less cost than surgical gastrojejunostomy. Techniques to perform this procedure include direct EUS-guided puncture and balloon-assisted and free-hand methods. Use of cautery-tipped lumen-apposing metal stent results in higher rates of technical success and shorter procedure times. Prospective studies are needed to compare EUS-gastrojejunostomy with enteral stenting and surgical gastrojejusntomy, and to clarify indications, optimal patient selection, and most appropriate method of technically performing this procedure.

A novel magnetic device for laparoscopic cholangiojejunostomy

BACKGROUND

Laparoscopic cholangiojejunostomy (LCJ) with hand-sewn technique is technically difficult and requires a long time to master. The purpose of this study was to assess the feasibility of LCJ using a novel magnetic compression device (MCD) in dogs.

METHODS

The concept of the purse-string technique of the circular stapler was used to design a novel MCD for LCJ. To test the feasibility of this MCD in a more clinically relevant situation, four dogs were subjected to bile duct ligation. When the diameter of their bile ducts reached 10 mm, LCJ using MCD was performed. The anastomotic time and expelling time of the magnets were assessed.

RESULTS

In the clinically relevant model of bile duct obstruction in dogs, LCJ created with this MCD yielded patent anastomoses. The LCJ procedure using this novel MCD was simple, and the mean anastomotic time was 12.9 ± 1.73 min. All animals recovered smoothly after the operation without complications. All magnets spontaneously passed through the rectum in 14.5 ± 2.08 d after LCJ.

CONCLUSIONS

LCJ in dogs using this novel MCD is feasible.

Endoscopic Bariatric Therapies

Obesity and its associated cardio-metabolic comorbidities have emerged as a global pandemic. The efficacy of various hypo-caloric diets and prescription drugs has been poor with respect to sustained weight loss. Recent advancements in endoscopic technology and techniques have opened a new field of minimally invasive endoscopic treatment options for combatting obesity both as a first line and adjunctive therapy. Presently, two endoscopic space-occupying devices in the form of intragastric balloons have received FDA approval for 6-month implantation in patients within a BMI range of 30-40 kg/m(2). Furthermore, full-thickness suturing has led to the development of primary endoscopic sleeve gastroplasty and Roux-en-Y gastric bypass revision as viable endoscopic alternatives to surgical approaches. These techniques have the potential to reduce adverse events, cost, and recovery times. Looking forward, a variety of promising and novel medical devices and endoscopic platforms that target obesity and diabetes are in various phases of development and investigation. The present review aims to discuss the current and forthcoming endoscopic bariatric therapies with emphasis on relevant procedural technique and review of available evidence.

Endoscopic Management

Endoscopic bariatric therapy consists of devices or procedures for primary weight loss or weight regain after Roux-en-Y gastric bypass that are placed or done endoscopically. In most cases, they result in less weight loss, but fewer complications than bariatric surgery; and more weight loss than lifestyle therapy or weight loss medications. These therapies are important advances to treat patients with obesity. This article focuses on therapies or devices with US Food and Drug Administration approval or those with current or planned US pivotal trials.

Endoscopic treatment of obesity

PURPOSE OF REVIEW

Obesity and its comorbid illnesses affect millions worldwide and are one of the major causes of preventable death in the world. Bariatric surgery is currently offered to individuals with a BMI greater than 40 kg/m or greater than 35 kg/m with obesity-related comorbidities such as hypertension or diabetes. Endoscopic bariatric therapies, with their reduced invasiveness and potential reversibility, may complement surgical approaches for achieving weight loss.

RECENT FINDINGS

At the time of this writing, two endoscopically placed intragastric balloons and an endoscopically placed aspiration tube have been approved by the Food and Drug Administration for weight loss purposes. Some devices employ a suturing platform to create plications or to appose two surfaces. Other endoscopic strategies under investigation to treat obesity-related comorbidities such as diabetes include duodenal mucosal resurfacing and creation of a partial jejunoileal diversion using self-assembling magnets.

SUMMARY

Current endoscopic methods for the treatment of obesity utilize various mechanisms, including occupying gastric volume, reducing gastric capacity, altering caloric absorption, or aspirating gastric contents. The long-term outcomes and cost-effectiveness of these strategies remain to be fully elucidated. The landscape of endoscopic bariatric therapies continues to evolve.

Weight loss endoscopy: Development, applications, and current status

Obesity and its comorbidities - including diabetes and obstructive sleep apnea - have taken a large and increasing toll on the United States and the rest of the world. The availability of commercial, clinical, and operative therapies for weight management have not been effective at a societal level. Endoscopic bariatric therapy is gaining acceptance as more effective than diet and lifestyle measures, and less invasive than bariatric surgery. Various endoscopic therapies are analogues of the restrictive or bypass components of bariatric surgery, utilizing gastric remodeling or intestinal anastomosis to achieve proven weight loss and metabolic benefits. Others, such as aspiration therapy, employ novel mechanisms of action. Intragastric balloons have recently been approved by the United States Food and Drug Administration, and a number of other technologies have completed large multicenter trials (such as AspireAssist aspiration therapy and Primary Obesity Surgery Endolumenal). Endoscopic sleeve gastroplasty and transoral outlet reduction for endoscopic revision of gastric bypass have proven safe and effective in a number of studies. As devices are approved for use, data will continue to accumulate for safety, effectiveness, and cost effectiveness. Bariatric endoscopists should be prepared to appropriately target and apply various endoscopic bariatric therapies in the context of a comprehensive long-term weight management program.

Minimally invasive entero-enteral dual-path bypass using self-assembling magnets

BACKGROUND

A minimally invasive method of entero-enteral bypass may be desirable for treatment of obstruction, obesity, or metabolic syndrome. We have developed a technology based on miniature self-assembling magnets which create large-caliber anastomoses (incisionless anastomosis system or IAS). The aim of this study was to assess (a) procedural characteristics of IAS deployment and (b) long-term integrity and patency of the resulting jejuno-ileal dual-path bypass.

METHODS

Endoscopic jejuno-ileal bypass creation using IAS magnets was performed in 8 Yorkshire pigs survived 3 months.

PROCEDURE

The jejunal magnet was endoscopically deployed. However, the ileal magnet required surgical delivery given restraints of porcine anatomy. A 5-mm enterotomy was created through which the ileal magnet was inserted using a modified laparoscopic delivery tool. Magnets were manually coupled. Pigs underwent serial endoscopies for anastomosis assessment. Three-month necropsies were performed, followed by pressure testing of anastomoses and histological analysis.

RESULTS

Jejuno-ileal bypass creation using self-assembling IAS magnets was successful in all 8 pigs (100 %). Patent, leak-free bypasses formed in all animals by day 10. All IAS magnets were expelled by day 12. Anastomoses were widely patent at 3 months, with mean maximal diameter of 30 mm. At necropsy, adhesions were minimal. Pressure testing confirmed superior integrity of anastomotic tissue. Histology showed full epithelialization across the anastomosis with no evidence of submucosal fibrosis or inflammation.

CONCLUSIONS

Entero-enteral bypass using self-assembling IAS magnets is safe and technically feasible in the porcine model. IAS magnets can be rapidly delivered endoscopically or through a modified laparoscopic device. Expulsion of fused magnets avoids retention of prosthetic material. Anastomoses are widely patent and fully re-epithelialized. Three-month pressure testing reveals anastomotic tissue to be as robust as native tissue, while necropsy and histology suggests minimal/absent tissue inflammation. In human anatomy, a fully endoscopic jejuno-ileal bypass using IAS magnets may be feasible.