Effect of electrical stimulation of the lower esophageal sphincter using endoscopically implanted temporary stimulation leads in patients with reflux disease

Endoscopic Advances in the Diagnosis and Management of Gastroesophageal Reflux Disease

Gastroesophageal reflux disease (GERD) is one of the most common diseases that occurs secondary to failure of the antireflux barrier system, resulting in the frequent and abnormal reflux of gastric contents to the esophagus. GERD is diagnosed in routine clinical practice based on the classic symptoms of heartburn and regurgitation. However, a subset of patients with atypical symptoms can pose challenges in diagnosing GERD. An esophagogastroduodenoscopy (EGD) is the most common initial diagnostic test used in the assessment for GERD, although half of these patients will not have any positive endoscopic findings suggestive of GERD. The advanced endoscopic techniques have improved the diagnostic yield of GERD diagnosis and its complications, such as Barrett's esophagus and early esophageal adenocarcinoma. These newer endoscopic tools can better detect subtle irregularities in the mucosa and vascular structures. The management options for GERD include lifestyle modifications, pharmacological therapy, and endoscopic and surgical interventions. The latest addition to the armamentarium is the minimally invasive endoscopic interventions in carefully selected patients, including the electrical stimulation of the LES, Antireflux mucosectomy, Radiofrequency therapy, Transoral Incisionless Fundoplication, Endoscopic Full-Thickness plication (GERDx™), and suturing devices. With the emergence of these advanced endoscopic techniques, it is crucial to understand their selection criteria, advantages, and disadvantages.

Advanced Endoscopic Imaging and Interventions in GERD: An Update and Future Directions

Gastroesophageal reflux disease (GERD) is one of the most common gastrointestinal diseases encountered in primary care and gastroenterology clinics. Most cases of GERD can be diagnosed based on clinical presentation and risk factors; however, some patients present with atypical symptoms, which can make diagnosis difficult. An esophagogastroduodenoscopy can be used to assist in diagnosis of GERD, though only half of these patients have visible endoscopic findings on standard white light endoscopy. This led to the development of new advanced endoscopic techniques that enhanced the diagnosis of GERD and related complications like squamous cell dysplasia, Barrett's esophagus, and early esophageal adenocarcinoma. This is conducted by improved detection of subtle irregularities in the mucosa and vascular structures through optical biopsies in real-time. Management of GERD includes lifestyle modifications, pharmacological therapy, endoscopic and surgical intervention. Minimally invasive endoscopic intervention can be an option in selected patients with small hiatal hernia and without complications of GERD. These endoscopic interventions include endoscopic fundoplication, endoscopic mucosal resection techniques, ablative techniques, creating mechanical barriers, and suturing and stapling devices. As these new advanced endoscopic techniques are emerging, data surrounding the indications, advantages and disadvantages of these techniques need a thorough understanding.

Recent advances in third space or intramural endoscopy

Third space endoscopy or intramural endoscopy is based on the principle that the deeper layers of the gastrointestinal tract can be accessed by tunneling in the submucosal space and maintaining the integrity of the overlying mucosa. The era of third space endoscopy started with peroral endoscopic myotomy (POEM) for treatment of achalasia and has expanded to treat various other gastrointestinal disorders. The technique is also currently used for treatment of refractory gastroparesis, Zenker’s diverticulum (ZD), resection of subepithelial tumors and early cancers of the gastrointestinal tract and Hirschsprung’s disease (HD). These procedures are rapidly emerging as minimally invasive alternatives to conventional surgery. They are safe and effective with excellent outcomes. This review focuses on the evolution and current applications of third space endoscopy in various gastrointestinal disorders. Key points: (1) Third space or intramural endoscopy initially started with the POEM procedure for treatment of achalasia; (2) Advancements in procedural techniques have expanded its application to treat other gastrointestinal disorders such as refractory gastroparesis, ZD, HD, resection of subepithelial tumors and early gastrointestinal cancers; (3) These procedures are highly effective with excellent outcomes and low complication rates; and (4) Third space endoscopic procedures are rapidly emerging as minimally invasive alternatives to conventional surgery.

Electrical stimulation therapy of the lower esophageal sphincter in GERD patients—a prospective single-center study

Background

Electrical stimulation therapy (EST) of the lower esophageal sphincter (LES) for gastro esophageal reflux disease (GERD) treatment increases LES pressure through chronic stimulation, with a low risk for gastrointestinal side effects and preservation of hiatal anatomy. The aim of this study was to evaluate the efficacy and safety of this novel technique in a high-output specialized reflux center.

Methods

This is a prospective single-center study including GERD patients indicated for anti-reflux therapy who consented to undergo LES-EST. Patients underwent prospective scheduled follow-up visits including interrogation of the stimulation device, clinical examination, and assessment of health-related quality of life (HRQL).

Results

Within a 4-year period, 37 LES-EST implantations were performed. The majority of patients were male (54.1%), mean BMI was 25.8 (SD 4.4), and mean age was 54.0 (SD 15.8). The median GERD HRQL composite score was 41 (IQR 21–49). Median total % of pH <4 was 10.1 (IQR 4.4–17.3). Six (16.2%) individuals underwent explantation of the entire system (IPG and leads) due to technical defect (n = 4) or failure of therapy (n = 2). HRQL score improved from 41 (IQR 21–49) to 8.50 (IQR 4.25–20.5, p < 0.001) and 9 (23.7%) patients were on at least occasional PPI treatment.

Conclusion

Due to the low rate of GI side effects and its minimal invasive character preserving the hiatal anatomy, this novel technique might find its place in anti-reflux surgery. However, the considerably high rate of device dysfunction needs further investigation.

Endoscopic treatments for GERD

Gastroesophageal reflux disease (GERD) is a condition with increasing prevalence and morbidity in the United States and worldwide. Despite advances in medical and surgical therapy over the last 30 years, gaps remain in the therapeutic profile of options. Flexible upper endoscopy offers the promise of filling in these gaps in a potentially minimally invasive approach. In this concise review, we focus on the plethora of endoluminal therapies available for the treatment of GERD. Therapies discussed include injectable agents, electrical stimulation of the lower esophageal sphincter, antireflux mucosectomy, radiofrequency ablation, and endoscopic suturing devices designed to create a fundoplication. As new endoscopic treatments become available, we come closer to the promise of the incisionless treatment of GERD. The known data surrounding the indications, benefits, and risks of these historical, current, and emerging approaches are reviewed in detail.

Design and Experimental Research of Implantable Lower Esophageal Sphincter Stimulator Based on Android Bluetooth

The aim of this study is to design an implantable Lower Esophageal Sphincter (LES) stimulator connected and controlled by an Android Bluetooth for the treatment of the gastroesophageal reflux disease (GERD). Then the animal experiments are carried out to evaluate the function of the system. The LES stimulator is composed of an external controller, an Android application (APP) via a smart phone and an implantable electronic device (IED). The external controller is designed to receive the settings parameters information sent by the Android APP via a Bluetooth module, and then is programmed to generate specific electrical stimulation pulses to the LES. The Android APP controls the start and stop of stimulation and the settings of stimulation parameters. The in vivo IED consists of a bipolar stimulating lead, a bipolar head connector and a receiving module. The bipolar stimulating lead is constructed of biocompatible materials: platinum-iridium electrodes which are coated with parylene and an outer silicone rubber sheathing. The size of the receiving module has been significantly decreased to 20×20×2 mm³, which is packaged by polydimethylsiloxane (PDMS) and proposed to deliver stimulation pulses from the external controller to the implantable lead. The one-month implantation experiment on rabbits has been performed to evaluate the LES stimulator. The results indicate that the proposed LES stimulator meets the requirements of the functions, effectiveness and safety.

State of Evidence in Minimally Invasive Management of Gastroesophageal Reflux: Findings of a Scoping Review

BACKGROUNDS & AIMS

Endoscopic management of gastroesophageal reflux disease (GERD) is being employed increasingly. The aim of this scoping review was to assess the volume of available evidence on the benefits of endoscopic and minimally invasive surgical therapies for GERD.

METHODS

criteria were used to perform an extensive literature search of data regarding the reported benefit of endoscopic therapies in GERD. Randomized controlled studies were utilized when available; however, data from observational studies were also reviewed.

RESULTS

A formal review of evidence was performed in 22 studies. Inclusion and exclusion criteria and study duration were noted and tabulated. Assessment of outcomes was based on symptoms and objective criteria reported by investigators. Reported outcomes for the interventions were tabulated under the heading of subjective (symptom scores, quality of life metrics, and change in proton pump inhibitor use) and objective metrics (pH parameters, endoscopic signs, and lower esophageal sphincter pressure changes). Adverse events were noted and tabulated. The majority of studies showed symptomatic and objective improvement of GERD with the device therapies. Adverse events were minimal. However, normalization of acid exposure occurred in about 50% of patients and, for some modalities, long-term durability is uncertain.

CONCLUSIONS

This scoping review revealed that the endoluminal and minimally invasive surgical devices for GERD therapy are a promising alternative to proton pump inhibitor therapy. Their place in the treatment algorithm for GERD will be better defined when important clinical parameters, especially durability of effect, are better understood.

Tailored modern GERD therapy - steps towards the development of an aid to guide personalized anti-reflux surgery

As the incidence of gastroesophageal reflux disease (GERD) is rising, surgical treatment is continuously advancing in an effort to minimize side effects, whilst maintaining efficacy. From a database of patients that underwent anti-reflux surgery at our institution between 2015 and 2018, the last 25 consecutive patients that underwent electrical stimulation (ES), magnetic sphincter augmentation (MSA) and Nissen fundoplication (NF), following a personalized treatment decision aid, were included in a comparative analysis. After preoperative evaluation each patient was referred for an ES, MSA or NF based on esophageal motility, hiatal hernia (HH) size and the patients’ preferences. Postoperative gastrointestinal symptoms and GERD-Health-related-Quality-of-Life were assessed. Preoperatively the median DCI (299 ES vs. 1523.5 MSA vs. 1132 NF, p = 0.001), HH size (0.5 cm ES vs. 1 cm MSA vs. 2 cm NF, p = 0.001) and presence of GERD-related symptoms differed significantly between the groups. The highest rate of postoperative dysphagia was seen after MSA (24%, p = 0.04), while the median GERD HRQL total score was equally distributed between the groups. The positive short-term postoperative outcome and patient satisfaction indicate that such an aid in treatment indication, based on esophageal motility, HH size and patient preference, represents a feasible tool for an ideal choice of operation and an individualized therapy approach.

Wirelessly Powered Endoscopically Implantable Devices into the Submucosa as the Possible Treatment of Gastroesophageal Reflux Disease

Gastroesophageal reflux disease (GERD) is a rather common disease with a prevalence reaching up to 10 or 20% in the western world. The most specific symptoms which point to the diagnosis of GERD are feelings of heartburn and the regurgitation of acidic stomach contents into the esophagus. However, a certain number of patients do not respond to standard therapy, and in these cases, it is necessary to resort to other treatment methods, such as laparoscopic fundoplication or electrostimulation of the lower esophageal sphincter. The aim of our work was to design and manufacture a miniature, battery-less stimulator to provide electric stimulation of the lower esophageal sphincter, which could be implanted deep into the submucosa of the distal esophagus. The main goal was to provide a battery-less system as opposed to traditional battery neurostimulators to reduce the size and weight of the device. An electronic prototype of a wirelessly powered implantable device was developed. We used animal models for the experiments. The device is designed to treat GERD via electrical stimulation of the muscularis propria. It is implanted into the submucosal pocket by the lower esophageal sphincter with an endoscope. This method of implantation is superior to esophageal stimulators used today because of very low invasiveness of the surgery. Bipolar neurostimulation via two gold-plated leads is provided. The device does not have any source of energy; it is powered wirelessly which reduces the risk of potential battery leakage and reduces the overall dimensions.

Alternative therapies for GERD: a way to personalized antireflux surgery

Gastroesophageal reflux disease (GERD) is a common disorder, known to affect about 20% of the Western population. Although conventional medical or surgical treatment has proven effective, there is certainly room for improvements. As only 10% of GERD patients are finally treated by antireflux surgery, a large therapeutic window exists. This treatment gap consists of patients who are not effectively treated with proton pump inhibitor but do not want to run the potential risks of conventional surgery. During the last two decades, several novel and intriguing options for the surgical treatment of GERD have been introduced and found their way into clinical use. The following summary will give an update of certain alternative therapeutic options to treat GERD or its pathological consequences.

Submucosal surgery: novel interventions in the third space

Traditional surgeries involve accessing body cavities, such as the abdomen and thorax, via incisions that divide skin and muscle. These operations result in postoperative pain and convalescence, and a risk of complications such as wound infection and hernia. The development of flexible endoscopy allowed diseases as varied as gastrointestinal bleeding and colon adenomas to be treated without incisions, but this technique is restricted by its endoluminal nature. A novel category of surgical endoscopic procedures has recently been developed that uses flexible endoscopic techniques to enter and access the submucosa of the gastrointestinal tract. Through this approach, the advantages of incisionless endoscopy can be applied to areas of the body that previously could only be reached with surgery. This Review introduces this new class of interventions by describing two examples of such submucosal surgeries for the treatment of benign gastrointestinal disease: per-oral endoscopic myotomy and per-oral pyloromyotomy. The approach to pre-procedure patient evaluation, operative technique, and the published outcomes are discussed, as well as potential future applications of similar techniques and procedures in this so-called third space.

Study on effects of electrical stimulation on rabbit esophageal body motility in vivo

Electric stimulation (ES) could induce contraction of intestinal smooth muscle. The aim of this study was to analyze the effects of ES on esophageal motility and the underlying mechanism in vivo. Twenty-eight rabbits were equipped with a pair of subserosa electrodes (connected to an electrical stimulator) in the lower segment of the esophagus. The ES signal consisted of bipolar rectangular pulse trains, lasting for 3 s, with different amplitudes (1 mA, 3 mA, 5 mA and 10 mA), and frequencies (10 Hz, 20 Hz and 50 Hz). The amplitude of the contraction was recognized by high-resolution manometry. The effect of ES was tested under anesthesia and following administration of atropine, phentolamine or L-NAME. ES induced esophageal contraction at the stimulated site. A statistically significant increase in esophageal pressure was observed when the stimulation amplitude was above 3 mA. The increase in esophageal pressure was associated with the amplitude of stimulus as well as the frequency. During stimulation, atropine, phentolamine and L-NAME had no effect on the increase of esophageal pressure induced by ES. These findings implied that ES induced esophageal contraction were not mediated via the NANC, adrenergic or cholinergic pathway. The amplitude of esophageal contraction was current and frequency dependent.

Some Non-FDA Approved Uses for Neuromodulation in Treating Autonomic Nervous System Disorders: A Discussion of the Preliminary Support

INTRODUCTION

Neuromodulation, including cavernous nerve stimulation, gastric electrical stimulation, deep brain stimulation, and vagus nerve stimulation, has been used with success in treating several functional disease conditions. The FDA has approved the use of neuromodulation for a few indications. We discuss in our review article the evidence of using neuromodulation for treating some important disorders involving the autonomic nervous system that are not currently FDA approved.

METHODS

This was a review article that included a systematic online web search for human clinical studies testing the efficacy of neuromodulation in treating erectile dysfunction, gastroparesis, gastroesophageal reflux disease, obesity, asthma, and heart failure. Our review includes all feasibility studies, nonrandomized clinical trials, and randomized controlled trials.

RESULTS

Our systematic literature search found 3, 4, 5, 4, 1, and 4 clinical studies relating to erectile dysfunction, gastroparesis, gastroesophageal reflux disease, obesity, asthma, and heart failure, respectively.

CONCLUSION

This review article shows preliminary support based on clinical studies that neuromodulation can be of benefit for patients with important autonomic nervous system disease conditions that are not currently approved by the FDA. All of these investigational uses are encouraging; further studies are necessary and warranted for all indications discussed in this review before achieving FDA approval.

Effect of electrical stimulation of the lower esophageal sphincter in gastroesophageal reflux disease patients refractory to proton pump inhibitors

AIM: To evaluate the efficacy of lower esophageal sphincter (LES)-electrical stimulation therapy (EST) in a subgroup of patients that reported only partial response to proton pump inhibitors (PPIs) therapy, compared to a group of patient with complete response.

METHODS: Bipolar stitch electrodes were laparoscopically placed in the LES and connected to an implantable pulse generator (EndoStim BV, the Hague, the Netherlands), placed subcutaneously in the anterior abdominal wall. Stimulation at 20 Hz, 215 μsec, 3-8 mAmp in 30 min sessions was delivered starting on day 1 post-implant. Patients were evaluated using gastroesophageal reflux disease (GERD)-HRQL, symptom diaries; esophageal pH and esophageal manometry before and up to 24 mo after therapy and results were compared between partial and complete responders.

RESULTS: Twenty-three patients with GERD on LES-EST were enrolled and received continuous per-protocol stimulation through 12 mo and 21 patients completed 24 mo of therapy. Of the 23 patients, 16 (8 male, mean age 52.1 ± 12 years) had incomplete response to PPIs prior to LES-EST, while 7 patients (5 male, mean age 52.7 ± 4.7) had complete response to PPIs. In the sub-group with incomplete response to PPIs, median (IQR) composite GERD-HRQL score improved significantly from 9.5 (9.0-10.0) at baseline on-PPI and 24.0 (20.8-26.3) at baseline off-PPI to 2.5 (0.0-4.0) at 12-mo and 0.0 (0.0-2.5) at 24-mo follow-up (P < 0.05 compared to on-and off-PPI at baseline). Median (IQR) % 24-h esophageal pH < 4.0 at baseline in this sub-group improved significantly from 9.8% (7.8-11.5) at baseline to 3.0% (1.9-6.3) at 12 mo (P < 0.001) and 4.6% (2.0-5.8) at 24 mo follow-up (P < 0.01). At their 24-mo follow-up, 9/11 patients in this sub-group were completely free of PPI use. These results were comparable to the sub-group that reported complete response to PPI therapy at baseline. No unanticipated implantation or stimulation-related adverse events, or any untoward sensation due to stimulation were reported in either group and LES-EST was safely tolerated by both groups.

CONCLUSION: LES-EST is safe and effective in controlling symptoms and esophageal acid exposure in GERD patients with incomplete response to PPIs. These results were comparable to those observed PPI responders.

Electrical stimulation for gastroesophageal reflux disease: current state of the art

Patients with gastroesophageal reflux disease (GERD) who are not satisfied with acid suppression therapy can benefit primarily from fundoplication, a surgical intervention. Fundoplication has been the standard surgical procedure for GERD. It is effective but is associated with adverse effects, resulting in a declining number of interventions, creating a need for alternative interventions that are effective, yet have a better adverse effect profile. One such alternative involves the application of electrical stimulation to the lower esophageal sphincter. A number of animal studies showed that such stimulation can increase resting lower esophageal sphincter pressure. An acute human study confirmed this effect, and was followed by two open-label studies, with a follow-up of up to 3 years. Results thus far show that the therapy is associated with a significant improvement in symptoms, a significant reduction in esophageal acid exposure, and a very good safety profile. This review will describe the evolution of electrical stimulation therapy for GERD, as well as the safety and efficacy of this intervention.

Electrical stimulation therapy of the lower oesophageal sphincter for refractory gastro-oesophageal reflux disease - interim results of an international multicentre trial

BACKGROUND

A previous single-centre study showed that lower oesophageal sphincter electrical stimulation therapy (LES-EST) in gastro-oesophageal reflux disease (GERD) patients improves reflux symptoms and decreases oesophageal acid exposure.

AIM

To evaluate safety and efficacy of LES-EST in GERD patients with incomplete response to proton pump inhibitors (PPIs) in a prospective, international, multicentre, open-label study.

METHODS

GERD patients, partially responsive to PPIs, received LES-EST. GERD health-related quality of life (GERD-HRQL), daily symptom diaries, quality of life scores, oesophageal acid exposure, and LES resting and residual pressure were measured before and after initiation of LES-EST. Stimulation sessions were optimised based on residual symptoms and oesophageal acid exposure.

RESULTS

Forty-four patients were enrolled and 6-month data from 41 patients are available. Hiatal repair was performed in 16 patients. One device-related, one procedure-related and one unrelated severe adverse event were reported. GERD-HRQL improved from 31.0 (IQR 26.2-36.8) off-PPI and 16.5 (IQR 9.0-22.8) on-PPI to 4 (IQR 1-8) at 3-month and 5 (IQR 3-9) at 6-month follow-up (P < 0.0001 vs. on- and off-PPI). Oesophageal acid exposure (pH < 4.0) improved from 10.0% (IQR 7.5-12.9) to 3.8% (IQR 1.9-12.3) at 3 months (P = 0.0027) and 4.4% (IQR 2.2-7.2) at 6 months (P < 0.0001).

CONCLUSIONS

These interim results show an acceptable safety record of LES-EST to date, combined with good short-term efficacy in GERD patients who are partially responsive to PPI therapy. A remarkable reduction in regurgitation symptoms, without the risk of intervention-requiring dysphagia may prove to be an advantage compared with other anti-reflux procedures. ClinicalTrials.gov Identifier: NCT01574339.

Refractory gastroesophageal reflux disease

Gastroesophageal reflux disease (GERD) is a condition that develops when the reflux of stomach contents into the esophagus causes troublesome symptoms, esophageal injury, and/or complications. Use of proton pump inhibitors (PPI) remains the standard therapy for GERD and is effective in most patients. Those whose symptoms are refractory to PPIs should be evaluated further and other treatment options should be considered, according to individual patient characteristics. Response to PPIs could be total (no symptoms), partial (residual breakthrough symptoms), or absent (no change in symptoms). Patients experiencing complete response do not usually need further management. Patients with partial response can be treated surgically or by using emerging endoscopic therapies. Patients who exhibit no response to PPI need further evaluation to rule out other causes.

Recent advances in treatment of gastroesophageal reflux disease by acupuncture

The purpose of this paper is to summarize the effect and mechanism of three kinds of common acupuncture methods for gastroesophageal reflux disease (GERD), and to analyze their advantages and disadvantages. Currently, there have been no uniform standards for the selection of acupuncture points and acupuncture frequency, which often depends on the experience. By using different evaluation methods, such as 24 h esophageal pH monitoring, high resolution manometry, and the quality of life and symptom scores, we found that treatment of GERD by acupuncture can improve patients' symptoms and quality of life.

Electrical stimulation therapy for gastroesophageal reflux disease

Electrical stimulation therapy (EST) of the lower esophageal sphincter is a relatively new technique for the treatment of gastroesophageal reflux disease (GERD) that may address the need of GERD patients, unsatisfied with acid suppressive medication and concerned with the potential risks of surgical fundoplication. In this paper we review available data about EST for GERD, including the development of the technique, implant procedure, safety and results from open-label trials. Two short-term temporary stimulation and long-term open-label human trials each were initiated to investigate the safety and efficacy of EST for the treatment of GERD and currently up to 2 years follow-up results are available. The results of EST are promising as the open-label studies have shown that EST is a safe technique with a significant improvement in both subjective outcomes of symptoms and objective outcomes of esophageal acid exposure in patients with GERD. However, long-term data from larger number of patients and a sham-controlled trial are required before EST can be conclusively advised as a viable treatment option for GERD patients.