Impedance-high resolution manometry analysis of patients with nonerosive reflux disease

The Milan score: A novel manometric tool for a more efficient diagnosis of gastro-esophageal reflux disease

OBJECTIVE

A definitive diagnosis of gastroesophageal reflux disease (GERD) depends on endoscopic and/or pH-study criteria. However, high resolution manometry (HRM) can identify factors predicting GERD, such as ineffective esophageal motility (IEM), esophago-gastric junction contractile integral (EGJ-CI), evaluating esophagogastric junction (EGJ) type and straight leg raise (SLR) maneuver response. We aimed to build and externally validate a manometric score (Milan Score) to stratify the risk and severity of the disease in patients undergoing HRM for suspected GERD.

METHODS

A population of 295 consecutive patients undergoing HRM and pH-study for persistent typical or atypical GERD symptoms was prospectively enrolled to build a model and a nomogram that provides a risk score for AET > 6%. Collected HRM data included IEM, EGJ-CI, EGJ type and SLR. A supplemental cohort of patients undergoing HRM and pH-study was also prospectively enrolled in 13 high-volume esophageal function laboratories across the world in order to validate the model. Discrimination and calibration were used to assess model's accuracy. Gastroesophageal reflux disease was defined as acid exposure time >6%.

RESULTS

Out of the analyzed variables, SLR response and EGJ subtype 3 had the highest impact on the score (odd ratio 18.20 and 3.87, respectively). The external validation cohort consisted of 233 patients. In the validation model, the corrected Harrel c-index was 0.90. The model-fitting optimism adjusted calibration slope was 0.93 and the integrated calibration index was 0.07, indicating good calibration.

CONCLUSIONS

A novel HRM score for GERD diagnosis has been created and validated. The MS might be a useful screening tool to stratify the risk and the severity of GERD, allowing a more comprehensive pathophysiologic assessment of the anti-reflux barrier.

TRIAL REGISTRATION

ClinicalTrials.gov (Identifier: NCT05851482).

Roles of swallowing and belching in different phenotypes of gastroesophageal reflux disease

BACKGROUND

The contributions of swallowing and belching to specific gastroesophageal reflux disease (GERD) phenotypes are unclear.

METHODS

This study retrospectively analyzed esophageal pH/impedance studies, comparing reflux events preceded by gastric belching (GB), supragastric belching (SGB), air swallowing, and liquid/solid swallowing based on reflux position, lower esophageal sphincter (LES) pressure, and acid exposure time (AET).

KEY RESULTS

20 GERD patients and 10 controls were studied. Upright GERD patients and controls had a higher proportion of reflux events with a preceding swallow or belch (0.64, 0.64) than the supine group (0.38, p = 0.043). The upright group and controls trended toward a higher proportion of reflux events preceded by overall swallowing (0.61, 0.50) and air swallowing (0.55, 0.48) than the supine group (0.32, 0.31 p = 0.064, p = 0.11), but the three groups had similar rates of liquid/solid swallowing (0.032, 0.024, 0.017, p = 0.69). LES pressure did not correlate with reflux events preceded by swallowing (R2  = 0.021, p = 0.44). There was a higher rate of events preceded by gastric belching in the control group (0.14) than in the upright (0.032) and supine groups (0.066, p = 0.049). LES pressure did not correlate with the rate of events preceded by belching (R2  = 0.000093, p = 0.96). Normal AET patients had a higher rate of events preceded by GB (0.12) than those with increased acid exposure (0.030, p = 0.0083), but the two groups had similar rates of preceding air (0.43, 0.47, p = 0.68), liquid/solid (0.018, 0.032, p = 0.30), and overall swallowing (0.44, 0.53, p = 0.38).

CONCLUSIONS AND INFERENCES

Swallowing more than belching is a dominant mechanism for reflux irrespective of GERD position, LES pressure, and AET.

Ineffective esophageal motility: The impact of change of criteria in Chicago Classification version 4.0 on predicting outcome after magnetic sphincter augmentation

BACKGROUND

The most recent update of the Chicago Classification (CCv4.0) attempts to provide a more clinically relevant definition for ineffective esophageal motility (IEM). The impact of this new definition on predicting outcome after antireflux surgery is unknown. The aim of this study was to compare utility of IEM diagnosis based on CCv4.0 to CCv3.0 in predicting surgical outcome after magnetic sphincter augmentation (MSA) and to assess any additional parameters that hold value in future definitions.

METHODS

Records of 336 patients who underwent MSA at our institution between 2013 and 2020 were reviewed. Preoperative manometry files were re-analyzed using both Chicago Classification version 3.0 (CCv3.0) and CCv4.0 definitions of IEM. The utility of each IEM definition in predicting surgical outcome was then compared. Individual manometric components and impedance data were also assessed.

KEY RESULTS

Immediate dysphagia was reported by 186 (55.4%) and persistent dysphagia by 42 (12.5%) patients. CCv3.0 IEM criteria were met by 37 (11%) and CCv4.0 IEM by 18 (5.4%) patients (p = 0.011). CCv3.0 and CCv4.0 IEM were equally poor predictors of immediate (AUC = 0.503 vs. 0.512, p = 0.7482) and persistent (AUC = 0.519 vs. 0.510, p = 0.7544) dysphagia. The predicted dysphagia probability of less than 70% bolus clearance (BC) was 17.4%, higher than CCv4.0 IEM at 16.7%. When BC was incorporated into CCv4.0 IEM criteria, the probability increased significantly to 30.0% (p = 0.0042).

CONCLUSIONS & INFERENCES

The CCv3.0 and CCv4.0 of IEM are poor predictors of dysphagia after MSA. Adding BC to the new definition improves its predictive utility and should be considered in future definitions.

Towards a better diagnosis of gastro esophageal reflux disease

INTRODUCTION

GERD is a common disorder and is characterized by the presence of typical or atypical symptoms. In GERD patients, the presence of mucosal alterations in endoscopy is detected in up to 30% of individuals. The clinical presentation of GERD patients may be complex and their management is challenging, due to the heterogeneous clinical presentation. The present review has been performed searching all relevant articles in this field, over the past years, using PubMed database.

AREAS COVERED

The diagnosis and management of GERD have been significantly improved in the last years due to the increasing availability of reflux monitoring techniques and the implementation of new procedures in the therapeutic armamentarium. Beside traditional impedance-pH variables, new metrics have been developed, increasing the diagnostic yield of reflux monitoring and better predicting the treatment response. Traditional pharmacological treatments include acid-suppressive-therapy and/or anti-acid. On the other hand, surgical treatment and, more recently, endoscopic procedures represent a promising field in the therapeutic approach.

EXPERT OPINION

Diagnosis and treatment of GERD still represent a challenging area. However, we believe that an accurate upfront evaluation is, nowadays, necessary in addressing patients with GERD to a more accurate diagnosis as well as to the best treatment options.

The Results From Up-Front Esophageal Testing Predict Proton Pump Inhibitor Response in Patients With Chronic Cough

INTRODUCTION

The clinical management of chronic cough patients is challenging, and their response to proton pump inhibitors (PPIs) is considered as unsatisfactory. Few data concerning the association between impedance-pH variables and PPI response in these patients are available. Mean nocturnal baseline impedance (MNBI) and postreflux swallow-induced peristaltic wave (PSPW) index increase the diagnostic yield of impedance-pH in gastroesophageal reflux disease.

METHODS

Demographic, clinical, and endoscopy findings; impedance-pH; and high-resolution manometry tracings from consecutive patients assessed for cough were evaluated. Univariable and multivariable regression models were generated to evaluate the association between impedance-pH and high-resolution manometry findings, endoscopic and clinical characteristics, and PPI response.

RESULTS

A total of 178 patients were included. Eighty-four of 178 cough patients (47.2%) displayed grade C-D erosive esophagitis or were characterized by a pathological acid exposure time (AET) and/or positive symptom association probability/symptom index. When also considering MNBI and PSPW, 135 of 178 patients (75.8%) were characterized by the evidence of reflux disease (P < 0.001). Eighty patients (44.9%) had cough responding to PPIs, whereas 98 (55.1%) were nonresponders (P = 0.071). At the receiver operating characteristic analysis, both PSPW index and MNBI were associated to PPI responsiveness. MNBI and PSPW index showed higher sensitivity in predicting PPI response compared with AET and symptom association probability/symptom index. The area under the curves of MNBI and PSPW index were significantly higher than that of AET (P < 0.01 for both comparisons). When patients were stratified according to AET and excluding those with erosive esophagitis, pathological MNBI or PSPW index, hiatal hernia, and hypomotility features were associated to PPI response in all groups.

DISCUSSION

Our results demonstrate the usefulness of an up-front esophageal testing in discriminating reflux-related cough patients and predicting PPI response.

Diagnostic yield and reliability of post-prandial high-resolution manometry and impedance-ph for detecting rumination and supragastric belching in PPI non-responders

BACKGROUND

Supragastric belching (SGB) and rumination are behavioral disorders associated with proton pump inhibitor (PPI) non-response and can be diagnosed using multichannel intraluminal impedance-pH (MII-pH) and post-prandial high-resolution impedance manometry (PPHRIM). This pilot study compared diagnostic yield and inter-rater agreement for SGB and rumination using MII-pH and PPHRIM.

METHODS

Three esophageal physiologists performed blinded interpretations of MII-pH and PPHRIM in 22 PPI non-responders. Raters selected from 4 diagnostic impressions (normal, GERD, behavioral disorders, GERD+behavioral disorders) without clinical context. Primary outcomes were diagnostic impressions compared against clinical gold standard impression, between raters, and between test modalities. Following a 28-month wash-out period, raters re-interpreted MII-pH with clinical context and under consensus definition of diagnostic criteria.

KEY RESULTS

Compared to gold standard, rater accuracy for presence of behavioral disorders ranged from 45 to 77% on MII-pH and 45-59% on PPHRIM. On MII-pH, inter-rater agreement was fair for diagnosis (ĸ0.32, p < 0.01) and suboptimal for presence of behavioral disorders (ĸ0.13, p = 0.14). On PPHRIM, inter-rater agreement was suboptimal for both diagnosis (ĸ0.03, p = 0.34) and presence of a behavioral disorder (ĸ-0.22, p = 0.96). Inter-rater agreement improved in post hoc MII-pH interpretations. Rumination was more frequently identified on PPHRIM (23, 35%) compared to MII-pH (7, 11%).

CONCLUSIONS AND INFERENCES

Diagnostic accuracy and inter-rater agreement are higher for MII-pH than PPHRIM, and behavioral disorders are more frequently identified on PPHRIM. Identifying behavioral disorders on MII-pH and PPHRIM has implications for clinical evaluation of PPI non-response; clinical context is essential for accurate study interpretation. Further work is needed to standardize definitions and interpretations.

Pressure and length of the lower esophageal sphincter as predictive indicators of therapeutic efficacy of baclofen for refractory gastroesophageal reflux-induced chronic cough

BACKGROUND

Therapeutic efficacy of baclofen is suboptimal in the treatment of refractory gastroesophageal reflux-induced chronic cough (GERC). The purpose of the study is to identify its therapeutic predictors in a prospective clinical study.

METHODS

138 patients with suspected refractory GERC were treated with baclofen. Before the therapy, all the patients underwent esophageal manometry and multichannel intraluminal impedance-pH monitoring to establish the diagnosis. After the efficacy of baclofen was evaluated, a stepwise logistic regression analysis was performed to identify the therapeutic predictors of baclofen and to establish a regression prediction model.

RESULTS

The overall response rate of baclofen treatment was 52.2% (72/138). The lower esophageal sphincter pressure (LESP) (odds ratio (OR) = 0.592, P = 0.000) and lower esophageal sphincter length (LESL) (OR = 0.144, P = 0.008) were independent predictors of baclofen efficacy. The optimal cut-off point to predict baclofen efficacy for LESP was 11.00 mmHg, with a sensitivity of 83.7% and specificity of 79.1% while that for LESL was 2.35 cm, with a sensitivity of 81.6% and specificity of 72.1%. The highest predictive specificity (90.7%) was achieved when both LESP and LESL were jointly used.

CONCLUSIONS

LESP and LESL may be used to screen the patients with refractory GERC suitable for baclofen therapy and help improve the therapeutic precision.

CLINICAL TRIAL REGISTRATION

ChiCTR- ONC-13003123.

The mechanisms associated with reflux episodes in ambulant subjects with gastro-esophageal reflux disease

BACKGROUND

The mechanisms associated with gastro-esophageal reflux (GER) episodes were studied using combined High-resolution Impedance Manometry (HRIM) and pH monitoring in ambulant subjects with different patterns of GERD.

METHODS

Sixteen subjects with mild-moderate esophagitis (Los Angeles (LA) grade A&B) (group A) and 11 subjects with severe esophagitis (LA grade C&D) or Barrett's esophagus (BE) were studied before and after a meal, resting, while walking, and during standardized exercise, using a HRIM and a pH probe.

KEY RESULTS

Post-prandial acid GER episodes were more common in group B (median 10 range (3-18) vs A (6.5 (0-18), p = 0.048). Postprandial acid clearance time was much longer in group B (median 0.71( 0.07-2.66 min) vs A (0.17 (0.04-2.44 min), p = 0.02). Transient lower esophageal sphincter relaxation (TLESR) was the most frequent mechanism associated with GER episodes in both groups. Post-prandial TLESRs with GER were more common in group B (median 17 (9-24) vs A 13.5 (7-34), p = 0.014), particularly during exercise (B 8 (6-9) vs A 6 (5-6.8), p = 0.007). Post-prandially TLESR with acid reflux increased during exercise in both groups (A rest median 2.4 (0-6.4) per hour vs exercise 4.7 (0-17.3), p = 0.005 and B 4 (0.8-9.6) vs 5.3 (2.7-13.3) per hour, p = 0.045).

CONCLUSIONS AND INFERENCES

TLESR was the most common mechanism associated with reflux episodes in all subjects. Acid reflux episodes were more common in subjects with severe esophagitis or BE and esophageal acid clearance was much slower. Post-prandial exercise increased TLESR with acid reflux and GERD patients should be encouraged to avoid exercise immediately after a meal.

Pathophysiology and treatment options for gastroesophageal reflux disease: looking beyond acid

Gastroesophageal reflux disease (GERD) is a disorder due to the retrograde flow of refluxate into the esophagus. Although GERD is a common clinical diagnosis, its pathogenesis is quite complex. As a result of its multifactorial development, many patients continue to experience adverse symptoms due to GERD despite prolonged acid suppression with proton pump inhibitor therapy. The pathogenesis of GERD involves an interplay of chemical, mechanical, psychologic, and neurologic mechanisms, which contribute to symptom presentation, diagnosis, and treatment. As such, GERD should be approached as a disorder beyond acid. This review will investigate the major factors that contribute to the development of GERD, including factors related to the refluxate, esophageal defenses, and factors that promote pathologic reflux into the esophagus. In reviewing GERD pathogenesis, this paper will highlight therapeutic advances, with mention of future opportunities of study when approaching GERD.

Understanding the relationship between esophageal motor disorders and reflux disease

INTRODUCTION

The management of gastro-esophageal reflux disease (GERD) patients is often complex as the clinical presentation is heterogeneous and the mechanisms underlying symptoms are multifactorial. In the past decades, investigations conducted with conventional manometry and, above all, the more accurate high resolution manometry (HRM), helped us in exploring the field of esophageal motility and in understanding the link between motor features and GERD pathogenesis.

AREAS COVERED

Several studies carried out with conventional manometry and HRM have confirmed a relevant role of esophageal motor function in GERD pathogenesis. In particular, HRM studies have shown a direct correlation between impaired esophageal body motility, disruption of the esophagogastric junction and reflux burden. These findings impact the clinical and therapeutical management of GERD patients. Moreover, HRM findings might be helpful in evaluating patients with proton pump inhibitor (PPI) resistance and inconclusive evidences of GERD.

EXPERT OPINION

The relationship between esophageal motility and GERD pathogenesis needs to be further evaluated by multicenter outcome studies involving a large number of GERD patients and healthy controls. However, other more promising areas could be progressed.

British Society of Gastroenterology guidelines for oesophageal manometry and oesophageal reflux monitoring

These guidelines on oesophageal manometry and gastro-oesophageal reflux monitoring supersede those produced in 2006. Since 2006 there have been significant technological advances, in particular, the development of high resolution manometry (HRM) and oesophageal impedance monitoring. The guidelines were developed by a guideline development group of patients and representatives of all the relevant professional groups using the Appraisal of Guidelines for Research and Evaluation (AGREE II) tool. A systematic literature search was performed and the GRADE (Grading of Recommendations Assessment, Development and Evaluation) tool was used to evaluate the quality of evidence and decide on the strength of the recommendations made. Key strong recommendations are made regarding the benefit of: (i) HRM over standard manometry in the investigation of dysphagia and, in particular, in characterising achalasia, (ii) adjunctive testing with larger volumes of water or solids during HRM, (iii) oesophageal manometry prior to antireflux surgery, (iv) pH/impedance monitoring in patients with reflux symptoms not responding to high dose proton pump inhibitors and (v) pH monitoring in all patients with reflux symptoms responsive to proton pump inhibitors in whom surgery is planned, but combined pH/impedance monitoring in those not responsive to proton pump inhibitors in whom surgery is planned. This work has been endorsed by the Clinical Services and Standards Committee of the British Society of Gastroenterology (BSG) under the auspices of the oesophageal section of the BSG.

The clinical significance of disorders of the motor function of the esophagus, stomach and duodenum

The purpose of the review is to determine the relationship between the clinical symptoms of diseases and disorders of the motor function of the esophagus, stomach and duodenal bulb, to present modern methods of their diagnosis and pathogenetic principles of treatment of diseases. Depending on the pathogenesis, it is possible to distinguish secondary motility disorders resulting from organic lesions, and primary (functional) changes. The emergence of clinical symptoms is associated with impaired motor - evacuation function of the digestive tract, which can be divided into two large groups: changes in the peristaltic activity of the organ wall and the work of the sphincter apparatus. The basis of the regulation of motility of the esophagus, stomach and duodenum is the interaction of nervous and humoral factors, the central processing of impulses is carried out in the cerebral cortex. In case of violation of the coordinated action of inhibitory and excitatory regulation systems, pathological contractile activity occurs, which manifests itself as hypo - or hyper - motor dyskinesia. X-ray, ultrasound, high resolution manometry of the esophagus, pH-meter, scintigraphy, computed tomography, antroduodenal manometry and a number of others are used to diagnose disorders of the motor function of the digestive tract, which can determine the mechanism of the development of symptoms and prescribe pathogenetic treatment to the patient. Thus, the occurrence of clinical symptoms is associated with changes in the motor - evacuation function of the digestive tract due to a violation of the coordinating action of inhibitory and excitatory factors. The use of modern diagnostic methods for the study of motor function makes it possible to determine the mechanism for the development of clinical symptoms, which allows the patient to prescribe an effective pathogenetic treatment.

The Utility of Esophageal Motility Testing in Gastroesophageal Reflux Disease (GERD)

PURPOSE OF REVIEW

Here, we discuss how esophageal motor testing plays important roles in patients with suspected gastroesophageal reflux disease (GERD). In addition to guiding appropriate placement of catheters for ambulatory reflux monitoring, esophageal high-resolution manometry (HRM) rules out confounding diagnoses, such as achalasia spectrum disorders, that can present with symptoms similar to that of GERD, but are managed very differently.

RECENT FINDINGS

HRM performed with impedance in the post-prandial setting (PP-HRIM) can assess for rumination syndrome or supragastric belching, which should be directed towards behavioral interventions. The recent GERD Classification of Motor Function recommends a hierarchical approach, focusing on (1) the esophagogastric junction (EGJ), (2) the esophageal body, and (3) esophageal contraction reserve, which can be assessed with provocative maneuvers at HRM, such as multiple rapid swallows (MRS). This approach can inform the appropriate tailoring of antireflux surgery. Novel esophageal motility metrics, such as the EGJ-contractile integral from HRM, or post-reflux swallow-induced peristaltic wave indices from 24-h pH-impedance monitoring, may also assist with GERD diagnosis. Assessment of esophageal motor function can contribute in a significant manner to the care of patients with suspected GERD, particularly when esophageal symptoms do not improve with antisecretory therapy, and/or when surgical or endoscopic antireflux therapies are under consideration.

Advancements in the use of manometry and impedance testing for esophageal functional disorders

The utilization of high-resolution manometry (HRM) has enhanced our understanding and assessment of esophageal motor disorders. Moreover, the combination of impedance technology with HRM (HRIM) has further improved our knowledge of esophageal physiology and the clinical evaluation of dysmotility, thanks to the addition of accurate measurement of bolus transit. Areas covered. This paper provides an overview of current knowledge in the use of HRIM for the study of esophageal functional disorders by reporting mainly the results of many publications and several systematic reviews in this field. Expert opinion. HRIM has represented a relevant improvement in the assessment of esophageal motility and has required the development of new metrics, such as the esophageal impedance integral ratio, the bolus flow time, the nadir impedance pressure and the impedance bolus height, which increase the evaluation of esophageal bolus transit. An extension of impedance is represented by functional lumen imaging probe (FLIP), which determines the biophysical properties and the distensibility of the esophagus and permits to detect contractility patterns not seen on HRM alone. We eagerly wait for a new and fruitful iteration of the Chicago Classification, now in version 3.0, which can cover the ongoing clinical experience of HRIM.

High-resolution Manometry Findings During Solid Swallows Correlate With Delayed Reflux Clearance and Acid Exposure Time in Non-erosive Reflux Disease Patients

Background/Aims

The role of esophageal motility in determining gastroesophageal reflux disease (GERD) severity has not been completely evaluated. A few studies have investigated high-resolution manometry (HRM) patterns during solid swallows. The present study evaluates the HRM patterns of non-erosive reflux disease (NERD) patients during both liquid and solid swallows and their correlation with the severity of GERD.

Methods

In 23 NERD patients and 15 healthy volunteers (HVs) HRM was performed during a standard solid meal in a seated position, followed by 24-hour impedance-pH monitoring.

Results

Of the 31 patients, 10 showed a pathological acid exposure time (AET; NERD patients), 13 a normal pH profile with positive symptom association probability (SAP; reflux hypersensitivity patients), and 8 normal AET and SAP (functional heartburn patients). Mean distal contractile integral and distal latency values, in all patient groups and HVs, were significantly higher during solid swallows. In the group of 10 NERD patients, the number of large breaks of the esophageal peristalsis was 16 out of 100 liquid swallows (16%) and 31 out of 171 solid swallows (18%). Fourteen out of 100 liquid swallows (14%) and 25 out of 171 solid swallows (15%) resulted ineffective. Mean reflux clearing time at multichannel intraluminal impedance-pH was 17.6 ± 3.7 seconds. NERD patients presented, during solid swallows, a significantly higher proportion of large peristaltic breaks and of ineffective swallows than reflux hypersensitivity and functional heartburn patients.

Conclusion

HRM during solid swallows reveals motor abnormalities, undetected during liquid swallows, which might be involved in delaying reflux and acid clearance in patients with GERD.

Modern diagnosis of GERD: the Lyon Consensus

Clinical history, questionnaire data and response to antisecretory therapy are insufficient to make a conclusive diagnosis of GERD in isolation, but are of value in determining need for further investigation. Conclusive evidence for reflux on oesophageal testing include advanced grade erosive oesophagitis (LA grades C and D), long-segment Barrett's mucosa or peptic strictures on endoscopy or distal oesophageal acid exposure time (AET) >6% on ambulatory pH or pH-impedance monitoring. A normal endoscopy does not exclude GERD, but provides supportive evidence refuting GERD in conjunction with distal AET <4% and <40 reflux episodes on pH-impedance monitoring off proton pump inhibitors. Reflux-symptom association on ambulatory reflux monitoring provides supportive evidence for reflux triggered symptoms, and may predict a better treatment outcome when present. When endoscopy and pH or pH-impedance monitoring are inconclusive, adjunctive evidence from biopsy findings (histopathology scores, dilated intercellular spaces), motor evaluation (hypotensive lower oesophageal sphincter, hiatus hernia and oesophageal body hypomotility on high-resolution manometry) and novel impedance metrics (baseline impedance, postreflux swallow-induced peristaltic wave index) can add confidence for a GERD diagnosis; however, diagnosis cannot be based on these findings alone. An assessment of anatomy, motor function, reflux burden and symptomatic phenotype will therefore help direct management. Future GERD management strategies should focus on defining individual patient phenotypes based on the level of refluxate exposure, mechanism of reflux, efficacy of clearance, underlying anatomy of the oesophagogastric junction and psychometrics defining symptomatic presentations.

What Is the Impact of High-Resolution Manometry in the Functional Diagnostic Workup of Gastroesophageal Reflux Disease?

International guidelines agree that high-resolution esophageal manometry (HRM) is an integral part of the diagnostic evaluation of patients with refractory reflux symptoms and should be performed before antireflux surgery. Its most important goal is to explore differential diagnoses, in particular major esophageal motility disturbances, that may be responsible for symptoms. HRM additionally provides insights into all relevant pathomechanisms of gastroesophageal reflux disease (GERD): It can reveal important information on the morphology and function of the esophagogastric junction (EGJ), the presence of a hiatus hernia, transient lower esophageal sphincter relaxations, and dysmotility of the esophageal body. To obtain this information, a 3-step hierarchical system has been proposed for the algorithmic characterization of esophageal motor function. The first step is to investigate the morphology and contractility of the EGJ, the second to monitor esophageal body motor patterns in response to water swallows, and the third to determine the contraction reserve in patients with abnormal esophageal motor function using provocation tests. Observations made with HRM can not only explain the cause of symptoms in GERD patients but may also have the potential to direct specific treatment.

Classification of esophageal motor findings in gastro-esophageal reflux disease: Conclusions from an international consensus group

BACKGROUND

High-resolution manometry (HRM) has resulted in new revelations regarding the pathophysiology of gastro-esophageal reflux disease (GERD). The impact of new HRM motor paradigms on reflux burden needs further definition, leading to a modern approach to motor testing in GERD.

METHODS

Focused literature searches were conducted, evaluating pathophysiology of GERD with emphasis on HRM. The results were discussed with an international group of experts to develop a consensus on the role of HRM in GERD. A proposed classification system for esophageal motor abnormalities associated with GERD was generated.

KEY RESULTS

Physiologic gastro-esophageal reflux is inherent in all humans, resulting from transient lower esophageal sphincter (LES) relaxations that allow venting of gastric air in the form of a belch. In pathological gastro-esophageal reflux, transient LES relaxations are accompanied by reflux of gastric contents. Structural disruption of the esophagogastric junction (EGJ) barrier, and incomplete clearance of the refluxate can contribute to abnormally high esophageal reflux burden that defines GERD. Esophageal HRM localizes the LES for pH and pH-impedance probe placement, and assesses esophageal body peristaltic performance prior to invasive antireflux therapies and antireflux surgery. Furthermore, HRM can assess EGJ and esophageal body mechanisms contributing to reflux, and exclude conditions that mimic GERD.

CONCLUSIONS & INFERENCES

Structural and motor EGJ and esophageal processes contribute to the pathophysiology of GERD. A classification scheme is proposed incorporating EGJ and esophageal motor findings, and contraction reserve on provocative tests during HRM.

Expert consensus document: Advances in the physiological assessment and diagnosis of GERD

GERD is a common condition worldwide. Key mechanisms of disease include abnormal oesophagogastric junction structure and function, and impaired oesophageal clearance. A therapeutic trial of acid-suppressive PPI therapy is often the initial management, with endoscopy performed in the setting of alarm symptoms and to exclude other conditions. If symptoms persist and endoscopy does not reveal evidence of GERD, oesophageal function tests are performed, including oesophageal manometry and ambulatory reflux monitoring. However, reflux episodes can be physiological, and some findings on endoscopy and manometry can be encountered in asymptomatic individuals without GERD symptoms. The diagnosis of GERD on the basis of functional oesophageal testing has been previously reported, but no updated expert recommendations on indications and the interpretation of oesophageal function testing in GERD has been made since the Porto consensus over a decade ago. In this Consensus Statement, we aim to describe modern oesophageal physiological tests and their analysis with an emphasis on establishing indications and consensus on interpretation parameters of oesophageal function testing for the evaluation of GERD in clinical practice. This document reflects the collective conclusions of the international GERD working group, incorporating existing data with expert consensus opinion.

Novel Prokinetic Acotiamide Reduces Transient Lower Esophageal Sphincter Relaxation in Healthy Subjects

BACKGROUND/AIMS

Currently, there is no study evaluating the effect of acotiamide on transient lower esophageal sphincter relaxations (TLESRs). The aim of this study was to evaluate the effect of acotiamide on TLESRs using simultaneous high-resolution manometry (HRM) and impedance-pH monitoring.

METHODS

Ten healthy subjects were enrolled. On day 1, subjects underwent HRM and impedance-pH recordings as a baseline. Subjects ate a 750-kcal liquid meal; recording was continued for 2 h while the subjects were in a sitting position. After the administration of acotiamide 100 mg three times a day for 1 week, subjects underwent HRM and impedance-pH recording under the same protocol.

RESULTS

A total of 208 TLESRs were identified at baseline. Acotiamide decreased the total number of TLESRs from 208 to 143 (p < 0.05). The rate of reflux events during TLESRs after acotiamide administration was similar to that at baseline (57% after acotiamide vs. 58% at baseline). Bolus clearance time was significantly reduced by acotiamide.

CONCLUSIONS

Acotiamide was believed to have the potential for reducing TLESRs and for enhancing esophageal bolus clearance in healthy volunteers. Future research is needed to determine whether the effects of acotiamide that reduce TLESRs and enhance esophageal motility could improve symptoms in patients with refractory gastroesophageal reflux disease.

Intra-bolus pressure and esophagogastric gradient, assessed with high-resolution manometry, are associated with acid exposure and proximal migration of refluxate

Trans-sphincteric pressure gradient (TSPG) seems to play a relevant role in eliciting refluxes during transient lower esophageal sphincter relaxations (TLESRs). Intra-bolus pressure (IBP) is considered to be correlated to esophageal wall tone. We aimed to evaluate the relationship between IBP, TSPG during TLESRs and the dynamic properties of refluxate in gastroesophageal reflux disease. Sixteen non-erosive reflux disease (NERD), 10 erosive disease (ERD) patients and 12 healthy volunteers (HVs), underwent 24-hour impedance-pH monitoring and combined high-resolution manometry-impedance before and 60 minutes. After a meal, ERD patients presented a significantly lower mean IBP (4.7 ± 1.6 mmHg) respect to NERD patients (8.9 ± 2.8 mmHg) and HVs (9.2 ± 3.2 mmHg). NERD patients with physiological abnormal acid exposure time showed a mean IBP (10.4 ± 3.1 mmHg) significantly higher than that in NERD with pathological abnormal acid exposure time (5.1 ± 1.5 mmHg). The TSPG value was significantly higher during TLESRs accompanied by reflux than during TLESRs not associated with reflux, both in patients and in HVs. A significant direct correlation was found between IBP, TSPG and proximal spread of refluxes in patients and in HVs. Gastroesophageal reflux disease patients display different degrees of esophageal distension. An increased compliance of the distal esophagus may accommodate larger volumes of refluxate and likely facilitates the injuries development. Higher TSPG values appear to facilitate the occurrence of refluxes during TLESRs. In patients with NERD, higher TSPG and IBP values favor proximal spread of refluxate and hence may play a relevant role in symptom generation.

Mechanisms of acid reflux and how refluxed Acid extends proximally in patients with non-erosive reflux disease

BACKGROUND/AIMS

The mechanisms that cause acid reflux in patients with non-erosive reflux disease (NERD), including those that determine how acid extends proximally, are not yet clear.

METHODS

Concurrent esophageal manometry and pH monitoring were performed for 3 h after a meal in 13 patients with NERD, 12 with mild reflux esophagitis (RE), and 13 healthy subjects (HS).

RESULTS

Transient lower esophageal sphincter (LES) relaxation (TLESR) was the major mechanism of acid reflux in all three groups. LES pressure did not differ between the groups. At 2 cm above the LES, there were no differences between the three groups in the number of TLESR-related acid reflux episodes, rate of TLESRs and rate of acid reflux during TLESR. However, at 7 cm above the LES, the rate of acid reflux during TLESRs was significantly higher in patients with NERD (mean ± SEM 42.3 ± 4.8) than in those with mild RE (28.0 ± 3.8) and HS (10.8 ± 2.5).

CONCLUSIONS

TLESRs are the sole motor events underlying acid reflux episodes in patients with NERD. Acid extends proximally more readily in patients with NERD than in HS and those with mild RE.

Mechanisms of Barrett's oesophagus (clinical): LOS dysfunction, hiatal hernia, peristaltic defects

Barrett's oesophagus, with the potential to develop into oesophageal adenocarcinoma (OAC), is a major complication of gastrooesophageal reflux disease (GORD). However, about 50% of patients developing OAC had no known GORD beforehand. Hence, while GORD symptoms, oesophagitis, and Barrett's have a number of common determinants (oesophagogastric junction (OGJ) incompetence, impaired oesophageal clearance mechanisms, hiatus hernia) they also have some independent determinants. Further, although excess oesophageal acid exposure plays a major role in the genesis of long-segment Barrett's oesophagus there is minimal evidence supporting this for short-segment Barrett's. Hence, these may have unique pathophysiological features as well. Long-segment Barrett's seems to share most, if not all, of the risk factors for oesophagitis, particularly high-grade oesophagitis. However, it is uncertain if OGJ function and acid clearance are more severely impaired in patients with long-segment Barrett's compared to patients with high-grade oesophagitis. With respect to short-segment Barrett's, the acid pocket may play an important pathogenic role. Conceptually, extension of the acid pocket into the distal oesophagus, also known as intra-sphincteric reflux, provides a mechanism or acid exposure of the distal osophageal mucosa without the occurrence of discrete reflux events, which are more likely to prompt reflux symptoms and lead to the development of oesophagitis. Hence, intra-sphincteric reflux related to extension of the acid/no acid interface at the proximal margin of the acid pocket may be key in the development of short segment Barrett's. However, currently this is still somewhat speculative and further studies are required to confirm this.

Acid infusion into the esophagus increases the number of meal-induced transient lower esophageal sphincter relaxations (TLESRs) in healthy volunteers

BACKGROUND

Transient lower esophageal sphincter relaxation (TLESR) is the major mechanism of gastroesophageal reflux (GER) but the regulation of TLESR by stimuli in the esophagus is incompletely understood. If stimuli in the esophagus can influence TLESR, then such regulation may perpetuate or limit GER. We addressed the hypothesis that acid in the esophagus enhances TLESRs.

METHODS

We evaluated the effect of acid infusion into the distal esophagus on TLESRs evoked by a standard meal in a paired randomized study in healthy subjects. TLESRs were evaluated by using high resolution manometry (HRM).

KEY RESULTS

We found that acid in the esophagus enhanced meal-induced TLESRs. Compared to control infusion the number of TLESRs (median [interquartile range]) was increased during 2 h following the acid infusion (11 [9-14] vs 17 [12.5-20], p < 0.01). The average duration of individual TLESRs was not affected. The time-course analysis revealed that a robust increase in TLESRs occurred already in the first hour when the number of TLESRs nearly doubled (6 [5.5-7.5] vs 11 [7.5-12.5], p < 0.05). In contrast to the enhancement of TLESRs, the number of swallows was not changed.

CONCLUSIONS & INFERENCES

The acid infusion into the esophagus increases the number of meal-induced TLESRs in healthy subjects. Our results provide evidence for the concept that the stimuli in the esophagus can influence TLESRs. The regulation of TLESR by stimuli in the esophagus may contribute to pathogenesis of GER in some patients.

Esophageal motility abnormalities in gastroesophageal reflux disease

Esophageal motility abnormalities are among the main factors implicated in the pathogenesis of gastroesophageal reflux disease. The recent introduction in clinical and research practice of novel esophageal testing has markedly improved our understanding of the mechanisms contributing to the development of gastroesophageal reflux disease, allowing a better management of patients with this disorder. In this context, the present article intends to provide an overview of the current literature about esophageal motility dysfunctions in patients with gastroesophageal reflux disease. Esophageal manometry, by recording intraluminal pressure, represents the gold standard to diagnose esophageal motility abnormalities. In particular, using novel techniques, such as high resolution manometry with or without concurrent intraluminal impedance monitoring, transient lower esophageal sphincter (LES) relaxations, hypotensive LES, ineffective esophageal peristalsis and bolus transit abnormalities have been better defined and strongly implicated in gastroesophageal reflux disease development. Overall, recent findings suggest that esophageal motility abnormalities are increasingly prevalent with increasing severity of reflux disease, from non-erosive reflux disease to erosive reflux disease and Barrett’s esophagus. Characterizing esophageal dysmotility among different subgroups of patients with reflux disease may represent a fundamental approach to properly diagnose these patients and, thus, to set up the best therapeutic management. Currently, surgery represents the only reliable way to restore the esophagogastric junction integrity and to reduce transient LES relaxations that are considered to be the predominant mechanism by which gastric contents can enter the esophagus. On that ground, more in depth future studies assessing the pathogenetic role of dysmotility in patients with reflux disease are warranted.