Introduction into the NHS of magnetic sphincter augmentation: an innovative surgical therapy for reflux - results and challenges

MAGNETIC SPHINCTER AUGMENTATION DEVICE FOR GASTROESOPHAGEAL REFLUX DISEASE: EFFECTIVE, BUT POSTOPERATIVE DYSPHAGIA AND RISK OF EROSION SHOULD NOT BE UNDERESTIMATED. A SYSTEMATIC REVIEW AND META-ANALYSIS

BACKGROUND

Magnetic ring (MSA) implantation in the esophagus is an alternative surgical procedure to fundoplication for the treatment of gastroesophageal reflux disease.

AIMS

The aim of this study was to analyse the effectiveness and safety of magnetic sphincter augmentation (MSA) in patients with gastroesophageal reflux disease (GERD).

METHODS

A systematic literature review of articles on MSA was performed using the Medical Literature Analysis and Retrieval System Online (Medline) database between 2008 and 2021, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A random-effect model was used to generate a pooled proportion with 95% confidence interval (CI) across all studies.

RESULTS

A total of 22 studies comprising 4,663 patients with MSA were analysed. Mean follow-up was 27.3 (7-108) months. The weighted pooled proportion of symptom improvement and patient satisfaction were 93% (95%CI 83-98%) and 85% (95%CI 78-90%), respectively. The mean DeMeester score (pre-MSA: 34.6 vs. post-MSA: 8.9, p=0.03) and GERD-HRQL score (pre-MSA: 25.8 vs. post-MSA: 4.4, p<0.0001) improved significantly after MSA. The proportion of patients taking proton pump inhibitor (PPIs) decreased from 92.8 to 12.4% (p<0.0001). The weighted pooled proportions of dysphagia, endoscopic dilatation and gas-related symptoms were 18, 13, and 3%, respectively. Esophageal erosion occurred in 1% of patients, but its risk significantly increased for every year of MSA use (odds ratio - OR 1.40, 95%CI 1.11-1.77, p=0.004). Device removal was needed in 4% of patients.

CONCLUSIONS

Although MSA is a very effective treatment modality for GERD, postoperative dysphagia is common and the risk of esophageal erosion increases over time. Further studies are needed to determine the long-term safety of MSA placement in patients with GERD.

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.

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.

Three-year clinical experience with magnetic sphincter augmentation and laparoscopic fundoplication

BACKGROUND

Magnetic sphincter augmentation (MSA) is a surgical intervention for gastroesophageal reflux disease (GERD) which has been evaluated in numerous studies and has shown beneficial effects. Long-term effectiveness data for MSA as well as laparoscopic fundoplication (LF) in patients with GERD are needed.

OBJECTIVE

The objective of this study was to evaluate the 3-year outcomes for MSA and LF in patients with GERD.

METHODS

This prospective, multi-center, observational registry study evaluated MSA and LF in clinical practice over 3 years (ClinicalTrials.gov identifier: NCT01624506). Data collection included baseline characteristics, reflux symptoms, medication use, satisfaction and complications. Post-surgical evaluations were collected at yearly intervals.

RESULTS

Between December 2009 and December 2014, 631 patients (465 MSA and 166 LF) were enrolled in the registry. Both MSA and LF resulted in improvements in total GERD-HRQL score (mean reduction in GERD-HRQL from baseline to 3 years post-surgery: MSA 22.0 to 4.6 and LF 23.6 to 4.9) and in satisfaction (GERD-HRQL satisfaction increase from baseline to 3 years: MSA 4.6% to 78.2% and LF 3.7% to 76.5%). Most patients were able to belch as needed with both therapies (MSA 97.6% and LF 91.7% at 3 years). MSA allowed a higher percentage of patients the ability to vomit as needed (MSA 91.2% and LF 68.0% at 3 years). PPI usage declined from baseline to 3 years for both groups after surgery (MSA 97.8% to 24.2% and LF 95.8% to 19.5%). The mean procedure time was shorter for MSA than for LF. Intraoperative and procedure-related complication rates (≤ 2%) were low for both therapies.

CONCLUSIONS

This 3-year prospective observational registry study contributes to the mounting evidence for the effectiveness of MSA and LF. Despite the more severe nature of GERD in the LF group, the clinical outcomes for MSA and LF were favorable from an effectiveness and safety standpoint.

Magnetic Sphincter Augmentation Superior to Proton Pump Inhibitors for Regurgitation in a 1-Year Randomized Trial

BACKGROUND & AIMS

Regurgitative gastroesophageal reflux disease (GERD) refractive to medical treatment is common and caused by mechanical failure of the anti-reflux barrier. We compared the effects of magnetic sphincter augmentation (MSA) with those of proton-pump inhibitors (PPIs) in a randomized trial.

METHODS

Patients with moderate to severe regurgitation (assessed by the foregut symptom questionnaire) despite once-daily PPI therapy (n = 152) were randomly assigned to groups given twice-daily PPIs (n = 102) or laparoscopic MSA (n = 50) at 20 sites, from July 2015 through February 2017. Patients answered questions from the foregut-specific reflux disease questionnaire and GERD health-related quality of life survey about regurgitation, heartburn, dysphagia, bloating, diarrhea, flatulence, and medication use, at baseline and 6 and 12 months after treatment. Six months after PPI therapy, MSA was offered to patients with persistent moderate to severe regurgitation and excess reflux episodes during impedance or pH testing on medication. Regurgitation, foregut scores, esophageal acid exposure, and adverse events were evaluated at 1 year.

RESULTS

Patients in the MSA group and those who crossed over to the MSA group after PPI therapy (n = 75) had similar outcomes. MSA resulted in control of regurgitation in 72/75 patients (96%); regurgitation control was independent of preoperative response to PPIs. Only 8/43 patients receiving PPIs (19%) reported control of regurgitation. Among the 75 patients who received MSA, 61 (81%) had improvements in GERD health-related quality of life improvement scores (greater than 50%) and 68 patients (91%) discontinued daily PPI use. Proportions of patients with dysphagia decreased from 15% to 7% (P < .005), bloating decreased from 55% to 25%, and esophageal acid exposure time decreased from 10.7% to 1.3% (P < .001) from study entry to 1-year after MSA (Combined P < .001). Seventy percent (48/69) of patients had pH normalization at study completion. MSA was not associated with any peri-operative events, device explants, erosions, or migrations.

CONCLUSIONS

In a prospective study, we found MSA to reduce regurgitation in 95% of patients with moderate to severe regurgitation despite once-daily PPI therapy. MSA is superior to twice-daily PPIs therapy in reducing regurgitation. Relief of regurgitation is sustained over 12 months. ClinicalTrials.gov no: NCT02505945.

LINX® reflux management system to bridge the "treatment gap" in gastroesophageal reflux disease: A systematic review of 35 studies

BACKGROUND

Gastroesophageal reflux disease (GERD) occurs when the reflux of stomach contents causes troublesome symptoms and/or complications. When medical therapy is insufficient, surgical therapy is indicated and, until now, Laparoscopic fundoplication (LF) constitutes the gold-standard method. However, magnetic sphincter augmentation (MSA) using the LINX® Reflux Management System has recently emerged and disputes the standard therapeutic approach.

AIM

To investigate the device's safety and efficacy in resolving GERD symptoms.

METHODS

This is a systematic review conducted in accordance to the PRISMA guidelines. We searched MEDLINE, Clinicaltrials.gov, EMBASE, Cochrane Central Register of Controlled Trials CENTRAL databases from inception until September 2019.

RESULTS

Overall, 35 studies with a total number of 2511 MSA patients were included and analyzed. Post-operative proton-pump inhibitor (PPI) cessation rates reached 100%, with less bloating symptoms and a better ability to belch or vomit in comparison to LF. Special patient groups (e.g., bariatric or large hiatal-hernias) had promising results too. The most common postoperative complication was dysphagia ranging between 6% and 83%. Dilation due to dysphagia occurred in 8% of patients with typical inclusion criteria. Esophageal erosion may occur in up to 0.03% of patients. Furthermore, a recent trial indicated MSA as an efficient alternative to double-dose PPIs in moderate-to-severe GERD.

CONCLUSION

The findings of our review suggest that MSA has the potential to bridge the treatment gap between maxed-out medical treatment and LF. However, further studies with longer follow-up are needed for a better elucidation of these results.

Systematic review of the introduction and evaluation of magnetic augmentation of the lower oesophageal sphincter for gastro-oesophageal reflux disease

BACKGROUND

Magnetic sphincter augmentation (MSA) is reported to be an innovative alternative to antireflux surgery for patients with gastro-oesophageal reflux disease. Although used in practice, little is known about how it has been evaluated. This study aimed to systematically summarize and appraise the reporting of MSA and its introduction into clinical practice, in the context of guidelines (such as IDEAL) for evaluating innovative surgical devices.

METHODS

Systematic searches were used to identify all published studies reporting MSA insertion. Data collected included patient selection, governance arrangements, surgeon expertise, technique description and outcome reporting.

RESULTS

Searches identified 587 abstracts; 39 full-text papers were included (1 RCT 5 cohort, 3 case-control, 25 case series, 5 case reports). Twenty-one followed US Food and Drug Administration eligibility criteria for MSA insertion. Twenty-six documented that ethical approval was obtained. Two reported that participating surgeons received training in MSA; 18 provided information about how MSA insertion was performed, although techniques varied between studies. Follow-up ranged from 4 weeks to 5 years; in 14 studies, it was less than 1 year.

CONCLUSION

Most studies on MSA lacked information about patient selection, governance, expertise, techniques and outcomes, or varied between studies. Currently, MSA is being used despite a lack of robust evidence for its effectiveness.

Laparoscopic magnetic sphincter augmentation versus fundoplication for gastroesophageal reflux disease: systematic review and pooled analysis

Magnetic sphincter augmentation (MSA) has been proposed as a less invasive, more appealing alternative intervention to fundoplication for the treatment of gastroesophageal reflux disease (GERD). The aim of this study was to evaluate clinical outcomes following MSA for GERD control in comparison with laparoscopic fundoplication. A systematic electronic search for articles was performed in Medline, Embase, Web of Science, and Cochrane Library for single-arm cohort studies or comparative studies (with fundoplication) evaluating the use of MSA. A random-effects meta-analysis for postoperative proton pump inhibitor (PPI) use, GERD-health-related quality of life (GERD-HRQOL), gas bloating, ability to belch, dysphagia, and reoperation was performed. The systematic review identified 6 comparative studies of MSA versus fundoplication and 13 single-cohort studies. Following MSA, only 13.2% required postoperative PPI therapy, 7.8% dilatation, 3.3% device removal or reoperation, and esophageal erosion was seen in 0.3%. There was no significant difference between the groups in requirement for postoperative PPI therapy (pooled odds ratio, POR = 1.08; 95%CI 0.40-2.95), GERD-HRQOL score (weighted mean difference, WMD = 0.34; 95%CI -0.70-1.37), dysphagia (POR = 0.94; 95%CI 0.57-1.55), and reoperation (POR = 1.23; 95%CI 0.26-5.8). However, when compared to fundoplication MSA was associated with significantly less gas bloating (POR = 0.34; 95%CI 0.16-0.71) and a greater ability to belch (POR = 12.34; 95%CI 6.43-23.7). In conclusion, magnetic sphincter augmentation achieves good GERD symptomatic control similar to that of fundoplication, with the benefit of less gas bloating. The safety of MSA also appears acceptable with only 3.3% of patients requiring device removal. There is an urgent need for randomized data directly comparing fundoplication with MSA for the treatment of GERD to truly evaluate the efficacy of this treatment approach.

A budget impact analysis of a magnetic sphincter augmentation device for the treatment of medication-refractory mechanical gastroesophageal reflux disease: a United States payer perspective

BACKGROUND

Medication-refractory gastroesophageal reflux disease (GERD) is sometimes treated with laparoscopic Nissen fundoplication (LNF); however, this is a non-reversible procedure associated with important side effects and the need for repeat surgery. Removable magnetic sphincter augmentation (MSA) devices are an alternative, effective, and safe treatment option for such patients who have some lower esophageal sphincter function. The objective of this study was to assess the economic impact of introducing MSA technology (i.e., LINX Reflux Management System) into current practice from a US-payer perspective.

METHODS

An economic budget impact model was developed over a 1-year time horizon that compared current treatment of GERD patients who are medically managed (but refractory) or receiving LNF to future treatment of GERD patients that included a mix of patients treated with medical management only, LNF, or MSA. Resources included within the analyses were index procedures (inpatient and outpatient use), reoperations (revisions and removals), readmissions, healthcare visits, diagnostic tests, procedures, and medications. Medicare payment rates were typically used to inform unit costs.

RESULTS

Assuming a hypothetical commercial insurance population of 1 million members, the base-case analysis estimated a net cost savings of $111,367 with introduction of the MSA. This translates to a savings of $0.01 per member per month. Results were largely driven by avoided inpatient procedures with use of the MSA device. Alternative analyses exploring the potential impact of increasing surgical volumes predicted that results would remain cost saving if the proportion of MSA market share taken from LNF was ≥ 90%.

CONCLUSIONS

This study predicts that the introduction of the MSA device would lead to favorable budget impact results for the treatment of medication-refractory mechanical GERD for commercial payers. Future analyses will benefit from inclusion of middle-ground treatments as well as longer time horizons.

Magnetic sphincter augmentation: Optimal patient selection and referral care pathways

Outcomes associated with magnetic sphincter augmentation (MSA) in patients with gastroesophageal reflux disease (GERD) have been reported, however the optimal population for MSA and the related patient care pathways have not been summarized. This Minireview presents evidence that describes the optimal patient population for MSA, delineates diagnostics to identify these patients, and outlines opportunities for improving GERD patient care pathways. Relevant publications from MEDLINE/EMBASE and guidelines were identified from 2000-2018. Clinical experts contextualized the evidence based on clinical experience. The optimal MSA population may be the 2.2-2.4% of GERD patients who, despite optimal medical management, continue experiencing symptoms of heartburn and/or uncontrolled regurgitation, have abnormal pH, and have intact esophageal function as determined by high resolution manometry. Diagnostic work-ups include ambulatory pH monitoring, high-resolution manometry, barium swallow, and esophagogastroduodenoscopy. GERD patients may present with a range of typical or atypical symptoms. In addition to primary care providers (PCPs) and gastroenterologists (GIs), other specialties involved may include otolaryngologists, allergists, pulmonologists, among others. Objective diagnostic testing is required to ascertain surgical necessity for GERD. Current referral pathways for GERD management are suboptimal. Opportunities exist for enabling patients, PCPs, GIs, and surgeons to act as a team in developing evidence-based optimal care plans.

Magnetic sphincter augmentation is an effective option for refractory duodeno-gastro-oesophageal reflux following Billroth II gastrectomy

Bile reflux into the gastric stump and then into the oesophagus is a common event after distal gastrectomy and Billroth II reconstruction. In addition to typical symptoms of nausea, epigastric pain and bile vomiting, acid reflux can also occur in patients with concomitant hiatus hernia and lower oesophageal sphincter incompetency. Diverting the bile away from the oesophagus by conversion into a Roux-en-Y anastomosis or by completion gastrectomy and Roux-en-Y esophagojejunostomy have so far represented the mainstay of treatment. We report the first case of magnetic sphincter augmentation to relieve refractory reflux symptoms after Billroth II gastrectomy. The procedure was performed through a laparoscopic approach and proved very effective at 1-year follow-up.