Evolution of a novel technology for gastroesophageal reflux disease: a safety perspective of magnetic sphincter augmentation

The Role of Surgical Intervention in Laryngopharyngeal Reflux Disease

This article covers surgical interventions for laryngopharyngeal reflux disease (LPRD), focusing on upper esophageal sphincter augmentation, fundoplication, and magnetic sphincter augmentation. It discusses indications, procedural details, and an overview of current evidence for surgical management of refractory LPRD.

Current Clinical Evidence for Magnetic Sphincter Augmentation: A Scoping Review

Background:

Magnetic sphincter augmentation (MSA) is an alternative treatment option to laparoscopic fundoplication (LF) for patients with gastroesophageal reflux disease. To date, over 40,000 devices have been implanted worldwide since first approval in Europe in 2010 and the USA in 2012. Despite this clinical reality, the long-term safety and effectiveness of the procedure continues to be questioned. This study aims to systematically summarize and appraise the currently available evidence for MSA relative to effectiveness, safety, and healthcare resource use.

Methods:

A systematic literature search was carried out to identify all clinical studies published in English, as of February 15, 2023. Required endpoints were safety, effectiveness, and cost effectiveness.

Results:

The systematic search identified 212 publications and 14 entries in study registries. After screening and full text analysis, 82 publications were included in qualitative synthesis. One RCT established superiority of MSA compared to twice daily proton-pump inhibitors with respect to the elimination of moderate to severe regurgitation (89% vs 10%, RR 0.11, 95% CI 0.06-0.20, P < 0.001). Eleven cohort studies comparing MSA to LF showed no statistical difference in safety profile and effectiveness measured by post-operative GERD-HRQL score. In addition, patients undergoing MSA significantly retained the ability to belch and vomit when compared to LF. These results were consistent in follow-up out to 7 years.

Conclusions:

LINX has been shown to provide long lasting relief to patients suffering from persistent GERD while maintaining an acceptable safety profile. As an outpatient day-procedure, MSA is cost effective with short recovery.

Medium-term outcomes after magnetic sphincter augmentation vs. fundoplication for reflux disease due to hiatal hernia: a propensity-score matched comparison in 282 patients

BACKGROUND

An increasing number of reflux patients opt for magnetic sphincter augmentation (MSA) instead of fundoplication. However, few studies compare the medium-term efficacy and safety of the procedures.

METHODS

We conducted a retrospective single-center analysis of consecutive MSA and Nissen fundoplication cases between 01/2015 and 06/2020. Patients underwent surgery, including hiatoplasty, for medical treatment-resistant reflux due to hiatal hernia. Surgical revision and proton pump inhibitor (PPI) reuptake rates were the primary outcomes. We also compared adverse event rates. Patients with severe preoperative dysphagia/motility disorders were assigned different treatment pathways and excluded from the analysis. We used propensity-score matching to reduce confounding between treatments.

RESULTS

Out of 411 eligible patients, 141 patients who underwent MSA and 141 with fundoplication had similar propensity scores and were analyzed. On average, patients were 55 ± 12 years old and overweight (BMI: 28 ± 5). At 3.9 years of mean follow-up, MSA was associated with lower surgical revision risk as compared to fundoplication (1.2% vs 3.0% per year, respectively; HR: 0.38; 95% CI 0.15-0.96; p = 0.04), and similar PPI-reuptake risk (2.6% vs 4.2% per year; HR: 0.59; 95% CI 0.30-1.16; p = 0.12). Adverse event rates during primary stay were similar (MSA vs. fundoplication: 1% vs. 3%, p = 0.68). Fewer patients experienced adverse events in the MSA group after discharge (24% vs. 33%, p = 0.11), driven by higher rates of self-limiting dysphagia (1% vs. 9%, p < 0.01) and gas/bloating (10% vs. 18%, p = 0.06) after fundoplication. Differences between MSA and fundoplication in dysphagia requiring diagnostic endoscopy (11% vs. 8%, p = 0.54) or surgical revision (2% vs. 1%, p = 1.0) were non-significant. The device explantation rate was 4% (5/141).

CONCLUSION

MSA reduces the re-operation risk compared to fundoplication and may decrease adverse event rates after discharge. Randomized head-to-head studies between available surgical options are needed.

Gastrointestinal devices: common and uncommon foreign bodies

Devices for the gastrointestinal tract are widely available and constantly advancing with less invasive techniques. They play a crucial role in diagnostic and therapeutic interventions and are commonly placed by interventional radiologists, gastroenterologists, and surgeons. These devices frequently appear in imaging studies, which verify their proper placement, identify any complications, or may be incidentally detected. Radiologists must be able to identify these devices at imaging and understand their intended purpose to assess their efficacy, detect complications such as incorrect positioning, and avoid misinterpreting them as abnormalities. Furthermore, many patients with these devices may require MRI, making assessing compatibility essential for safe patient care. This review seeks to provide a succinct and practical handbook for radiologists regarding both common and uncommon gastrointestinal devices. In addition to textual descriptions of clinical indications, imaging findings, complications, and MRI compatibility, the review incorporates a summary table as a quick reference point for key information and illustrative images for each device.

Assessing the Reproducibility of Research Based on the Food and Drug Administration Manufacturer and User Facility Device Experience Data

OBJECTIVE

This article aims to assess the reproducibility of Manufacturer and User Facility Device Experience (MAUDE) data-driven studies by analyzing the data queries used in their research processes.

METHODS

Studies using MAUDE data were sourced from PubMed by searching for "MAUDE" or "Manufacturer and User Facility Device Experience" in titles or abstracts. We manually chose articles with executable queries. The reproducibility of each query was assessed by replicating it in the MAUDE Application Programming Interface. The reproducibility of a query is determined by a reproducibility coefficient that ranges from 0.95 to 1.05. This coefficient is calculated by comparing the number of medical device reports (MDRs) returned by the reproduced queries to the number of reported MDRs in the original studies. We also computed the reproducibility ratio, which is the fraction of reproducible queries in subgroups divided by the query complexity, the device category, and the presence of a data processing flow.

RESULTS

As of August 8, 2022, we identified 523 articles from which 336 contained queries, and 60 of these were executable. Among these, 14 queries were reproducible. Queries using a single field like product code, product class, or brand name showed higher reproducibility (50%, 33.3%, 31.3%) compared with other fields (8.3%, P = 0.037). Single-category device queries exhibited a higher reproducibility ratio than multicategory ones, but without statistical significance (27.1% versus 8.3%, P = 0.321). Studies including a data processing flow had a higher reproducibility ratio than those without, although this difference was not statistically significant (42.9% versus 17.4%, P = 0.107).

CONCLUSIONS

Our findings indicate that the reproducibility of queries in MAUDE data-driven studies is limited. Enhancing this requires the development of more effective MAUDE data query strategies and improved application programming interfaces.

Predictability of magnetic sphincter augmentation device explantation: a nomogram-based scoring tool from an experienced quaternary center

BACKGROUND

Magnetic sphincter augmentation (MSA) explantation is an uncommon occurrence, and there are limited studies characterizing factors predictive of MSA explantation. This study aimed to create a nomogram to aid in determining the probability of explantation in patients before MSA implantation.

METHODS

An institutional review board-approved, prospectively maintained database was retrospectively reviewed for all patients undergoing antireflux surgery between February 2015 and May 2023. All patients who underwent MSA-related procedures were included. Patients were divided into 2 groups, explant group and nonexplant group, and differences were analyzed. A multivariable logistic regression model was fitted to identify independent risk factors for predicting MSA explantation, and a nomogram-based scoring tool was developed.

RESULTS

There were 227 patients (134 females and 93 males) with a mean age of 51.4 years. The explant group included 28 patients (12.3%), whereas the nonexplant group included 199 patients (87.7%). Patient sociodemographic characteristics, medical comorbidities, preoperative testing results, and surgical history were included in the analysis. The multivariable regression model resulted in 4 significant variables that were included in the nomogram. These included preoperative DeMeester score, preoperative gastroesophageal reflux disease health-related quality of life score, preoperative distal contractile integral value on manometry, and body mass index. Based on these variables, a scoring nomogram was developed with values ranging from 0 to 18.

CONCLUSION

Our data were used to develop a scoring calculator capable of predicting the probability of MSA explantation. This scoring tool can guide preoperative patient selection and treatment decisions.

Foregut Erosion Related to Biomedical Implants: A Scoping Review

Introduction: Biomedical devices implanted transabdominally have gained popularity over the past 50 years in the treatment of gastroesophageal reflux disease, paraesophageal hiatal hernia, and morbid obesity. Device-related foregut erosions (FEs) represent a challenging event that demands special attention owing to the potential of severe postoperative complications and death. Purpose: The aim was to provide an overview of full-thickness foregut injury leading to erosion associated with four types of biomedical devices. Methods: The study was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR). PubMed, EMBASE, and Web of Science databases were queried until December 31, 2023. Eligible studies included all articles reporting data, management, and outcomes on device-related FE. Results: Overall, 132 articless were included for a total of 1292 patients suffering from device-related FE. Four different devices were included: the Angelchik antireflux prosthesis (AAP) (n = 25), nonabsorbable mesh for crural repair (n = 60), adjustable gastric banding (n = 1156), and magnetic sphincter augmentation device (n = 51). The elapsed time from device implant to erosion ranged from 1 to 480 months. Most commonly reported symptoms were dysphagia and epigastric pain, while acute presentation was reported rarely and mainly for gastric banding. The technique for device removal evolved from more invasive open approaches toward minimally invasive and endoscopic techniques. Esophagectomy and gastrectomy were mostly reported for nonabsorbable mesh FE. Overall mortality was .17%. Conclusions: Device-related FE is rare but may occur many years after AAP, nonabsorbable mesh, adjustable gastric banding, and magnetic sphincter augmentation implant. FE-related mortality is infrequent, however, increased postoperative morbidity and the need for esophagogastric resection were observed for nonabsorbable mesh-reinforced cruroplasty.

Safety profile of magnetic sphincter augmentation for gastroesophageal reflux disease

Background

The magnetic sphincter augmentation (MSA) procedure is an effective treatment for gastroesophageal reflux disease (GERD). Adverse events requiring MSA device removal are rare, but the true prevalence and incidence may be underestimated.

Methods

Retrospective study on a prospectively collected database. Patients who underwent MSA procedure between March 2007 and September 2021 in two tertiary-care referral centers for esophageal surgery were included. The trend of MSA explant, the changes in the sizing technique and crura repair over the years, the technique of explant, and the clinical outcomes of the revisional procedure were reviewed.

Results

Out of 397 consecutive patients, 50 (12.4%) underwent MSA removal, with a median time to explant of 39.5 [IQR = 53.7] months. Main symptoms leading to removal were dysphagia (43.2%), heartburn (25%), and epigastric pain (13.6%). Erosion occurred in 2.5% of patients. Smaller (12- and 13-bead) devices were the ones most frequently explanted. The majority of the explants were performed laparoscopically with endoscopic assistance. There was no perioperative morbidity, and the median length of stay was 2.8 ± 1.4 days. After 2014, changes in sizing technique and crura repair resulted in a decreased incidence of explants from 23% to 5% (p < 0.0001). Multivariate analysis confirmed the protective role of added bead units [HR 0.06 (95% CI = 0.001-0.220); p < 0.000].

Conclusion

Oversizing and full mediastinal dissection with posterior hiatoplasty may improve the outcomes of the MSA procedure and possibly reduce removal rates.

Magnetic sphincter augmentation may limit access to magnetic resonance imaging

Magnetic sphincter augmentation (MSA) is an alternative surgical treatment for gastroesophageal reflux disease; however, >1.5 T magnetic resonance imaging (MRI) is contraindicated for patients who have undergone MSA with the LINX Reflux Management System (Torax Medical, Inc. Shoreview, Minnesota, USA). This drawback can impose a barrier to access of MRI, and cases of surgical removal of the device to enable patients to undergo MRI have been reported. To evaluate access to MRI for patients with an MSA device, we conducted a structured telephone interview with all diagnostic imaging providers in Arizona in 2022. In 2022, only 54 of 110 (49.1%) locations that provide MRI services had at least one 1.5 T or lower MRI scanner. The rapid replacement of 1.5 T MRI scanners by more advanced technology may limit healthcare options and create an access barrier for patients with an MSA device.

Longer-term outcomes of gastroesophageal reflux disease treated with magnetic sphincter augmentation

Surgical intervention for gastroesophageal reflux disease (GERD) has historically been limited to fundoplication. Magnetic sphincter augmentation (MSA) is a less invasive alternative that was introduced 15 years ago, and it may have a superior side-effect profile. To date, however, there has been just a single published study reporting outcomes in a UK population. This study reports quality-of-life (QOL) outcomes and antacid use in patients undergoing MSA, with a particular focus on postoperative symptoms and those with severe reflux. A single-center cohort study was carried out to assess the QOL outcomes and report long-term safety outcomes in patients undergoing MSA. GERD-health-related quality of life (GERD-HRQL) and Reflux Symptom Index (RSI) scores were collected preoperatively, and immediately postoperatively, at 1-, 2-, 3-, and 5-year follow-up time points. All patients underwent preoperative esophagogastroduodenoscopy, impedance, and manometry. Two hundred and two patients underwent laparoscopic MSA over 9 years. The median preoperative GERD-HRQL score was 31, and the median RSI score was 17. There was a reduction in all scores from preoperative values to each time point, which was sustained at 5-year follow-up; 13% of patients had a preoperative DeMeester score of >50, and their median preoperative GERD-HRQL and RSI scores were 32 and 15.5, respectively. These were reduced to 0 at the most recent follow-up. There was a significant reduction in antacid use at all postoperative time points. Postoperative dilatation was necessary in 7.4% of patients, and the device was removed in 1.4%. Erosion occurred in no patients. MSA is safe and effective at reducing symptom burden and improving QOL scores in patients with both esophageal and laryngopharyngeal symptoms, including those with severe reflux.

Is magnetic sphincter augmentation indicated in patients with laryngopharyngeal reflux?

Up to 30% of patients with gastroesophageal reflux disease (GERD) suffer from laryngopharyngeal reflux (LPR) with symptoms, as chronic cough, laryngitis, or asthma. Besides life-style modifications and medical acid suppression, laparoscopic fundoplication is an established treatment option. Treatment-related side effects after laparoscopic fundoplication have to be weighted against LPR symptom control in 30-85% of patients after surgery. Magnetic sphincter augmentation (MSA) is described as an effective alternative to fundoplication for surgical treatment of GERD. However, evidence on the efficacy of MSA in patients with LPR is very limited. Preliminary data on the results of MSA treating LPR symptoms in patients with acid and weakly acid reflux are promising; showing comparable results to laparoscopic fundoplication by providing the potential of decrease side effects.

The role of magnetic sphincter augmentation (MSA) in the gastroesophageal reflux disease (GERD) treatment pathway: the gastroenterology perspective

Magnetic sphincter augmentation (MSA) is a surgical intervention for well-characterized gastroesophageal reflux disease (GERD), where the esophagogastric junction barrier is augmented using a bracelet of magnetized titanium beads. MSA could be an attractive option for patients with documented GERD who wish to avoid long-term pharmacologic therapy or whose symptoms are not adequately managed with lifestyle modifications and pharmacologic therapy. The 'ideal' MSA patient is one with prominent regurgitation, without dysphagia or esophageal motor dysfunction, with objective evidence of GERD on upper endoscopy and/or ambulatory reflux monitoring. Appropriate candidates with significant hiatus hernia may pursue MSA with concomitant hiatus hernia repair. The increasing adoption of MSA in the GERD treatment pathway reflects research that shows benefits in long-term outcomes and healthcare costs compared with other established therapies in appropriate clinical settings.

Real-world evidence with magnetic sphincter augmentation for gastroesophageal reflux disease: a scoping review

Background

The burden of gastroesophageal reflux disease (GERD) is high, with up to 30% of the Western population reporting reflux-related symptoms with or without hiatal hernia. Magnetic sphincter augmentation (MSA) is a standardized laparoscopic procedure for patients who are dissatisfied with medical therapy and for those with early-stage disease who would not usually be considered ideal candidates for fundoplication. The MSA device is manufactured in different sizes and is designed to augment the physiologic barrier to reflux by magnetic force.

Methods

An extensive scoping review was performed to provide a map of current evidence with respect to MSA, to identify gaps in knowledge, and to make recommendations for future research. All the authors contributed to the literature search in PubMed and Web of Science and contributed to summarizing the evidence.

Results

Magnetic sphincter augmentation, especially in combination with crural repair, is effective in reducing GERD symptoms, proton pump inhibitor use, and esophageal acid exposure, and in improving patients’ quality of life. Safety issues such as device erosion or migration have been rare and not associated with mortality. The MSA device can be removed laparoscopically if necessary, thereby preserving the option of fundoplication or other therapies in the future. Contraindication to scanning in high-power Tesla magnetic resonance systems remains a potential limitation of the MSA procedure. High-resolution manometry and functional lumen imaging probes appear to be promising tools to predict procedural outcomes by improving reflux control and reducing the incidence of dysphagia.

Conclusion

A consensus on acquisition and interpretation of high-resolution manometry and impedance planimetry data is needed to gain better understanding of physiology, to improve patient selection, and to pave the way for a personalized surgical approach in antireflux surgery.

Feasibility and Efficacy of Magnetic Sphincter Augmentation for the Management of Gastroesophageal Reflux Disease Post-Sleeve Gastrectomy for Obesity

BACKGROUND

Patients with medically intractable GERD after laparoscopic sleeve gastrectomy (LSG) have limited surgical options. Fundoplication is difficult post-LSG. Roux-en-Y gastric bypass may be used as a conversion procedure but is more invasive with potential for serious complications. Magnetic sphincter augmentation (MSA) is a less invasive GERD treatment alternative. The objective of this study was to assess safety and efficacy outcomes of MSA after LSG.

METHODS

The primary outcome of this observational, multicenter, single-arm prospective study was the rate of serious device and/or procedure-related adverse events (AEs). The efficacy of the LINX device was measured comparing baseline to 12-month post-implant reductions in distal acid exposure, GERD-HRQL score, and average daily PPI usage.

RESULTS

Thirty subjects who underwent MSA implantation were followed 12 months post-implant. No unanticipated adverse device effects were observed. There were two adverse events deemed serious (dysphagia, pain, 6.7%) which resolved without sequelae. GERD-HRQL scores showed significant improvement (80.8%, P < 0.001), and reduction in daily PPI usage was seen (95.8%, P < 0.001). Forty-four percent of subjects demonstrated normalization or >  = 50% reduction of total distal acid exposure time (baseline 16.2%, 12 months 11%; P = 0.038).

CONCLUSIONS

Post-LSG, MSA showed an overall improvement of GERD symptoms, and reduction in PPI use with explants within anticipated range along with improvement in distal esophageal acid exposure time.

Long-term clinical and functional results of magnetic sphincter augmentation

Magnetic sphincter augmentation (MSA) was introduced in 2007 as an alternative surgical procedure for patients with gastroesophageal reflux disease (GERD). The majority of data since MSA's introduction has focused on short and intermediate-term results, demonstrating safety and high efficacy in terms of reflux symptom control, freedom from proton pump inhibitor use and normalization of distal esophageal acid exposure. However, GERD is a chronic condition that demands a long-term solution. Limited available data from studies reporting outcomes at 5 years or later following MSA demonstrate that the promising short- and mid-term efficacy and safety profile of MSA remains relatively constant in the long term. Compared with Nissen fundoplication, MSA has a much lower rate of gas-bloat and inability to belch at a short-term follow-up, a difference that persists in the long-term. The most common complaint after MSA at a short-term follow-up is dysphagia. However, limited data suggest dysphagia rates largely decrease by 5 years. Dysphagia is the most common indication for dilation and device removal in both early- and long-term studies. However, the overall rates of dilation and removal are similar in short- and long-term reports, suggesting the majority of these procedures are performed in the short-term period after device implantation. The indications and standard practices of MSA have evolved over time. Long-term outcome data currently available are all from patient cohorts who were selected for MSA under early restricted indications and outdated regimens. Therefore, further long-term studies are needed to corroborate the preliminary, yet encouraging long-term results.

Magnetic sphincter augmentation device removal: surgical technique and results at medium-term follow-up

Background

The magnetic sphincter augmentation (MSA) device has become a common option for the treatment of gastroesophageal reflux disease (GERD). Knowledge of MSA-related complications, indications for removal, and techniques are puzzled. With this study, we aimed to evaluate indications, techniques for removal, surgical approach, and outcomes with MSA removal.

Methods

This is an observational singe-center study. Patients were followed up regularly with endoscopy, pH monitoring, and assessed for specific gastroesophageal reflux disease health-related quality of life (GERD-HRQL) and generic short-form 36 (SF-36) quality of life.

Results

Five patients underwent MSA explant. Four patients were males and the median age was 47 years (range 44–55). Heartburn, epigastric/chest pain, and dysphagia were commonly reported. The median implant duration was 46 months (range 31–72). A laparoscopic approach was adopted in all patients. Intraoperative findings included normal anatomy (40%), herniation in the mediastinum (40%), and erosion (20%). The most common anti-reflux procedures were Dor (n = 2), Toupet (n = 2), and anterior partial fundoplication (n = 1). The median operative time was 145 min (range 60–185), and the median hospital length of stay was 4 days (range 3–6). The median postoperative follow-up was 41 months (range 12–51). At the last follow-up, 80% of patients were off PPI; the GERD-HRQL and SF-36 questionnaire were improved with DeMeester score and esophageal acid exposure normalization.

Conclusion

The MSA device can be safely explanted through a single-stage laparoscopic procedure. Tailoring a fundoplication, according to preoperative patient symptoms and intraoperative findings, seems feasible and safe with a promising trend toward improved symptoms and quality of life.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00423-021-02294-7.

Current status of gastroesophageal reflux disease after sleeve gastrectomy: Still a long way to go

Obesity is a public health concern that is becoming increasingly more serious around the world. Bariatric surgery has become more prevalent due to the obesity epidemic worldwide. Sleeve gastrectomy (SG) is one of the most popular procedures which is safe and efficient. Despite all its favorable features, however, there is an increasing evidence from the literature that the long-term incidence of gastroesophageal reflux disease (GERD) is likely to represent the Achilles' heel of this procedure. Management of severe reflux after SG usually requires revisional surgery. The relationship between SG and GERD needs to be better ascertained in order to prevent related complications, such as esophageal adenocarcinoma. This review attempts to elucidate the effect of SG on GERD and the postoperative management of reflux disease according to recent literature in the hope of drawing the attention of clinicians to postoperative gastroesophageal reflux and guiding the optimal management strategy associated with this "troublesome complication".