Variation in esophageal physiology testing in clinical practice: Results from an international survey

Diagnostic differences in high-resolution esophageal motility in a large Mexican cohort based on geographic distribution

High-resolution esophageal manometry [HRM] has become the gold standard for the evaluation of esophageal motility disorders. It is unclear whether there are HRM differences in diagnostic outcome based on regional or geographic distribution. The diagnostic outcome of HRM in a diverse geographical population of Mexico was compared and determined if there is variability in diagnostic results among referral centers. Consecutive patients referred for HRM during 2016-2020 were included. Four major referral centers in Mexico participated in the study: northeastern, southeastern, and central (Mexico City, two centers). All studies were interpreted by experienced investigators using Chicago Classification 3 and the same technology. A total of 2293 consecutive patients were included. More abnormal studies were found in the center (61.3%) versus south (45.8%) or north (45.2%) P < 0.001. Higher prevalence of achalasia was noted in the south (21.5%) versus center (12.4%) versus north (9.5%) P < 0.001. Hypercontractile disorders were more common in the north (11.0%) versus the south (5.2%) or the center (3.6%) P.001. A higher frequency of weak peristalsis occurred in the center (76.8%) versus the north (74.2%) or the south (69.2%) P < 0.033. Gastroesophageal junction obstruction was diagnosed in (7.2%) in the center versus the (5.3%) in the north and (4.2%) in the south p.141 (ns). This is the first study to address the diagnostic outcome of HRM in diverse geographical regions of Mexico. We identified several significant diagnostic differences across geographical centers. Our study provides the basis for further analysis of the causes contributing to these differences.

Esophageal motor abnormalities in gastroesophageal reflux disorders

Gastroesophageal reflux disease (GERD), a prevalent condition with multifactorial pathogenesis, involves esophageal motor dysmotility as a key contributing factor to its development. When suspected GERD patients have an inadequate response to proton-pump inhibitor (PPI) therapy and normal upper endoscopy results, high-resolution manometry (HRM) is utilized to rule out alternative diagnosis such as achalasia spectrum disorders, rumination, or supragastric belching. At present, HRM continues to provide supportive evidence for diagnosing GERD and determining the appropriate treatment. This review focuses on the existing understanding of the connection between esophageal motor findings and the pathogenesis of GERD, along with the significance of esophageal HRM in managing GERD patients. The International GERD Consensus Working Group introduced a three-step method, assessing the esophagogastric junction (EGJ), esophageal body motility, and contraction reserve with multiple rapid swallow (MRS) maneuvers. Crucial HRM abnormalities in GERD include frequent transient lower esophageal sphincter relaxations, disrupted EGJ, and esophageal body hypomotility. Emerging HRM metrics like EGJ-contractile integral and innovative provocative maneuver like straight leg raise have the potential to enhance our understanding of factors contributing to GERD, thereby increasing the value of HRM performed in patients who experience symptoms suspected of GERD.

Assessing the diagnostic yield of achalasia using provocative testing in high-resolution esophageal manometry: Serial diagnostic study

BACKGROUND

Chicago Classification v4.0 recommends that if achalasia is demonstrated with single water swallows (SWS); provocative testing is not required. We determine whether provocative testing in patients with suspected achalasia can change manometric findings and reproduce symptoms.

METHODS

Between 2016 and 2022, 127 consecutive manometry studies of patients with achalasia were retrospectively analyzed. All patients underwent SWS, a solid meal (SM) and/or a rapid drink challenge (RDC). Demographic data, fluoroscopy, gastroscopy, and pre-and post-treatment Eckardt scores were collated.

KEY RESULTS

Of 127 achalasia patients (50.6 ± 16.6 years and 54.6% male), all completed a SM and 116 (91.3%) completed RDC; overall 83 were naïve (65.4%) to previous therapy. 15.4% patients with normal integrated relaxation pressure (IRP) on SWS demonstrated obstruction with RDC. SM gave a different achalasia phenotype in 44.9% of patients (p ⟨ 0.001). Twelve patients with normal IRP during SWS had persistent/recurrent obstruction during provocative testing; 83.3% had previous achalasia therapy. None of 13 patients with Type III (TIII) achalasia with SWS exhibited a change in manometric findings with provocative testing. Impedance bolus heights were lower in patients with TIII achalasia and those with normal IRP with SWS. During the SM, symptoms were reproduced in 56.7% of patients. Forty-six of 103 patients (44.7%) underwent therapy based upon the final achalasia subtype which was defined by the provocative test result of the high-resolution manometry (HRM) study. All treatments were effective, regardless of the achalasia subtype.

CONCLUSIONS AND INFERENCES

Manometric findings remain unchanged when TIII achalasia is diagnosed with SWS. In patients with normal IRP, Type I, or Type II achalasia during SWS, provocative testing can alter achalasia phenotype or uncover achalasia where diagnosis is unclear. Further, it can reproduce symptoms. Such findings can personalize and guide effective therapeutic decisions.

A Short History of High-Resolution Esophageal Manometry

High-resolution esophageal manometry (HRM) utilizes sufficient pressure sensors such that intraluminal pressure is monitored as a continuum along luminal length, similar to time viewed as a continuum on polygraph tracings in 'conventional' manometry. When HRM is coupled with pressure topography plotting, and pressure amplitude is transformed into spectral colors with isobaric areas indicated by same-colored regions, "Clouse plots" are generated. HRM has several advantages compared to the technology that it replaced: (1) the contractility of the entire esophagus can be viewed simultaneously in a uniform standardized format, (2) standardized objective metrics of peristaltic and sphincter function can be systematically applied for interpretation, and (3) topographic patterns of contractility are more easily recognized with greater reproducibility. Leveraging these advantages led to the current standard for the interpretation of clinical esophageal HRM studies, the Chicago Classification (CC), now in its fourth iteration. Compared to conventional manometry, HRM has vastly improved the sensitivity for detecting achalasia, largely due to the objectivity and accuracy of identification of impaired esophagogastric junction (EGJ) relaxation. Additionally, it has led to the subcategorization of achalasia into three clinically relevant subtypes, differentiated by the contractile function of the esophageal body, and identified an additional disorder of EGJ outflow obstruction wherein esophageal peristalsis is preserved. Headway has also been made in understanding hypocontractile and hypercontractile conditions. In summary, HRM and the CC process have revolutionized our understanding of esophageal motility and motility disorders. Moving forward, there will always be remaining challenges, but we now have the tools to meet them.

Advancing high-resolution manometry: evaluating the use of multiple rapid swallows versus apple viscous swallows in clinical practice

BACKGROUND

High-Resolution Manometry (HRM) with provocative maneuvers, such as Multiple Rapid Swallows (MRS) and Apple Viscous Swallows (AVS), is commonly utilized to diagnose esophageal disorders. Increasing standardization in HRM protocol can help save time and reduce patient discomfort. This study assesses AVS and MRS to determine their respective benefits and limitations.

METHODS

Retrospective reviews were performed on 100 patients to analyze their AVS and/or MRS results. Parameters included abnormal motility patterns, tolerance, and DCI. Diagnostic benefits from MRS and AVS were assessed. Based on the previous studies, additional benefit from MRS was defined as detection of good peristaltic reserve, weak peristaltic reserve, or an abnormal motility/pressurization pattern. Additional benefit from AVS was defined as detection of IEM features or abnormal motility/pressurization pattern.

RESULTS

When patients completed both MRS and AVS (n = 70), MRS provided additional benefit in assessing 36% of patients, while AVS provided additional benefit in 19% of patients (p < 0.0001). Furthermore, MRS detected significantly more abnormal motility/pressurization patterns than AVS (27% MRS; 8% AVS; p = 0.0005). Two unique strengths of AVS were higher tolerance for test completion (p = 0.009) and better detection of severe hypokinetic disorders in 4% of patients, which were missed by MRS.

CONCLUSIONS

MRS may uniquely identify abnormal motility/pressurization patterns, such as paradoxical LES response, distal pressurization, hypercontractile, and spasm patterns. These findings argue for a tailored approach when selecting provocative testing. MRS may be more useful for patients with abnormal pathophysiology, while AVS may help to supplement MRS in detecting severe hypokinetic disorders in preoperative management.

The semirecumbent position for high-resolution esophageal manometry. Results of a feasibility study

OBJECTIVE

Normative values for high-resolution manometry (HRM) have been obtained with the patient lying supine. The aim of the study was to compare supine, semirecumbent and sitting positions during HRM in terms of variation in normative metrics, diagnostic yield, and patient's comfort.

METHODS

A prospective, single-center feasibility study was planned in consecutive patients referred to the esophageal function laboratory. In each of the three positions, 10 consecutive 5 ml water swallows and three 10 ml multiple rapid swallows were administered. Validated reflux questionnaires were administered prior to the test, and a visual analogue scale (VAS) assessing the patient's comfort after the test.

RESULTS

Twenty patients presenting with gastroesophageal reflux symptoms completed the study protocol. The intra-abdominal segment of the lower esophageal sphincter was significantly longer in the sitting position (P = 0.013), and the multiple rapid swallow distal contractile integral was lowest in the supine position (P = 0.012). The VAS comfort score did not significantly differ in the three body positions (P = 0.295). The concordance in the final diagnosis was 80% for semirecumbent vs. sitting (kappa = 0.15; P = 0.001), 70% for supine vs. sitting and 65.0% for semirecumbent vs. supine.

CONCLUSION

Compared to the supine position, both the semirecumbent and sitting position seems to provide similar advantages. HRM metrics and the final manometric diagnosis may be affected by body position, but complementary maneuvers, such are the rapid drink challenge, can resolve diagnostic discrepancies and improve the overall accuracy of the test.

Clinical usefulness of esophageal high resolution manometry and adjunctive tests: An update

High resolution manometry (HRM), developed from conventional manometry, is the gold standard for assessment of esophageal motor function worldwide. The Chicago Classification, now in its fourth iteration, is the modern standard for HRM categorization of esophageal motility disorders. The HRM protocol has expanded from the original 10 supine swallow standard, to include upright swallows, and provocative maneuvers such as multiple rapid swallows, rapid drink challenge and standardized test meal. Impedance has been incorporated into HRM for visualization of bolus clearance. Futhermore, barium radiography and functional lumen imaging probe complement HRM when evidence of esophagogastric junction obstruction is inconclusive. The biggest impact of HRM is in the improved diagnosis and subtyping of achalasia spectrum disorders, with implications on management. Spastic disorders and absent contractility are better characterized. Within the reflux spectrum, HRM provides definition of morphology and tone of the esophagogastric junction, and assesses integrity of esophageal body peristalsis, which have pathophysiologic implications for reflux and its clearance. HRM provides characterization of behavioral disorders such as supragastric belching and rumination syndrome, which can mimic reflux disease. Thus, HRM has revolutionized the evaluation of esophageal motor function, and has expanded the utility of esophageal manometry in clinical practice.

Impact of patient position on esophageal motility disorders using high-resolution esophageal manometry with impedance (HREMI): supine versus upright swallows

BACKGROUND

High-resolution esophageal manometry with impedance (HREMI) performed with supine patient positioning is used to evaluate patients for esophageal dysmotility. However, most patients experience symptoms related to esophageal dysmotility when eating or drinking upright. The aims of this study are to: (1) compare HREMI metrics in supine versus upright position; and (2) determine if upright position alters motility characterization of patients.

METHODS

HREMI of twelve wet swallows in supine position and five wet swallows in upright position were performed on normal subjects (NS) and consecutive patients. Chicago Classification v3.0 (CC) diagnoses were evaluated in the supine position and a modified version of the Chicago Classification system was used in the upright position using normative upright values for DCI and IRP.

RESULTS

DCI decreased in NS by 414 mmHg × cm × sec (p = 0.001) and patients by 613 mmHg × cm × sec (p < 0.001). IRP decreased in NS by 6.2 mmHg (p < 0.001) and patients by 4.6 mmHg (p < 0.001). The rate of successful bolus clearance decreased in the upright position in patients by 11% (p < 0.001), but no statistically significant differences were observed in NS. 82 of 200 patients (41%) had a change in CC diagnosis in the upright position. Bolus clearance in the upright position varied in patients depending on their diagnosis in the upright position.

CONCLUSIONS

Upright swallows had lower LES, IRP, DCI and UES pressures in both normal subjects and patients with decreased bolus clearance in patients. Upright positioning can alter esophageal motility patterns and enhance diagnostic yield. Thus, upright swallows supplement supine swallows to help characterize esophageal dysmotility.

Variations in Clinical Practice of Esophageal High-resolution Manometry: A Nationwide Survey

Background/Aims

Esophageal high-resolution manometry (HRM) enables the comprehensive evaluation of the esophageal motor function. However, protocols are not uniform and clinical practices vary widely among institutions. This study aims to understand the current HRM practice in Korea.

Methods

The survey was sent via email through the Korean Society of Neurogastroenterology and Motility. The questions covered descriptive information, preparation, techniques, analysis, and reporting of esophageal HRM.

Results

The survey was completed in 32 (74.4%) out of 43 centers, including 24 tertiary and 8 secondary referral centers. Of the 32 centers, 25 (78.1%) performed HRM in a sitting position, while 7 centers (21.9%) reported performing HRM in a supine position. All the centers utilized single wet swallows as a standard, but the volume, frequency, and interval between swallows varied widely. Sixteen centers (50.0%) applied adjunctive tests, including multiple rapid swallows (n = 16) and rapid drink challenges (n = 9). Parameters assessed and documented in the report were similar. In addition to the assessment of the esophagogastric junction and esophageal body, 27 centers (84.8%) and 18 centers (56.3%) included measurements for the upper esophageal sphincter and the pharynx, respectively, in the HRM protocol.

Conclusions

We found a variation in the available HRM practice among centers, even though they broadly agreed in the data analysis. Efforts are needed to develop a standardized protocol for HRM measurement.

Management of Ineffective Esophageal Hypomotility

Esophageal hypomotility in general and especially ineffective esophageal motility according to the Chicago criteria of primary motility disorders of the esophagus, is one of the most frequently diagnosed motility disorders on high resolution manometry and results in a large number of patients visiting gastroenterologists. Most patients with esophageal hypomotility present with gastroesophageal reflux symptoms or dysphagia. The clinical relevance of the motility pattern, however, is not well established but seems to be correlated with disease severity in reflux patients. The correlation with dysphagia is less clear. Prokinetic agents are commonly prescribed as first line pharmacologic intervention to target esophageal smooth muscle contractility and improve esophageal motor functions. However, the beneficial effects of these medications are limited and only confined to some specific drugs. Serotonergic agents, including buspirone, mosapride and prucalopride have been shown to improve parameters of esophageal motility although the effect on symptoms is less clear. Understanding on the complex correlation between esophageal hypomotility and esophageal symptoms as well as the limited evidence of prokinetic agents is necessary for physicians to appropriately manage patients with Ineffective Esophageal Motility (IEM).

Chicago classification version 4.0© technical review: Update on standard high-resolution manometry protocol for the assessment of esophageal motility

The Chicago Classification v4.0 (CCv4.0) is the updated classification scheme for esophageal motility disorders using metrics from high-resolution manometry (HRM). A key feature of CCv.4.0 is the more rigorous and expansive protocol that incorporates single wet swallows acquired in different positions (supine, upright) and provocative testing, including multiple rapid swallows and rapid drink challenge. Additionally, solid bolus swallows, solid test meal, and/or pharmacologic provocation can be used to identify clinically relevant motility disorders and other conditions (eg, rumination) that occur during and after meals. The acquisition and analysis for performing these tests and the evidence supporting their inclusion in the Chicago Classification protocol is detailed in this technical review. Provocative tests are designed to increase the diagnostic sensitivity and specificity of HRM studies for disorders of esophageal motility. These changes attempt to minimize ambiguity in prior iterations of Chicago Classification, decrease the proportion of HRM studies that deliver inconclusive diagnoses and increase the number of patients with a clinically relevant diagnosis that can direct effective therapy. Another aim in establishing a standard manometry protocol for motility laboratories around the world is to facilitate procedural consistency, improve diagnostic reliability, and promote collaborative research.

Patterns of esophageal dysmotility elicited by multiple rapid swallows

BACKGROUND

High-resolution manometry (HRM) is a gastrointestinal motility diagnostic system that measures intraluminal pressures using closely aligned sensors. Multiple rapid swallows (MRS) are used in conjunction with HRM to assess esophageal physiology prior to anti-reflux and hiatal hernia procedures.

METHODS

A retrospective, qualitative study was conducted on 90 patients who underwent HRM with MRS in a single community clinic. 80 patients met the inclusion criteria. MRS testing consisted of rapid 2 mL swallows in 2-3 s intervals with patients in a seated, upright position. Clinical information was reviewed including indications for HRM, prior diagnostic workup, manometry, distal contractile integral (DCI), and integrated residual pressure (IRP). HRM studies were visualized using Manoview Analysis Software v3.0 (Medtronic).

RESULTS

Certain esophageal dysmotility and pressurization manometry patterns were previously undetected on HRM alone. In our study, the addition of MRS was clinically helpful in (1) assessing contraction reserve, (2) highlighting features of jackhammer, (3) stimulating esophageal spasm, and (4) visualizing distal esophageal pressurization pattern with mechanical obstruction. Additionally, abnormal pathophysiology such as (5) paradoxical LES contraction (achalasia) and (6) loss of deglutition inhibition were identified. MRS had a diagnostic utility of 21.25% (n = 17) among the 80 patients. An intolerance rate of 7.7% (n = 7) was observed in patients unable to complete the protocol.

CONCLUSIONS

Augmentation of HRM with MRS produces unique manometric features that have clinical utility in uncovering esophageal disorders. MRS provocation testing is a practical, inexpensive, well-tolerated addition to HRM that may yield useful clinical information to guide complicated diagnoses and medical management.

The added value of symptom analysis during a rapid drink challenge in high-resolution esophageal manometry

INTRODUCTION

Patients with esophageal symptoms often remain with an uncertain diagnosis after high-resolution manometry.

AIM

To determine the added value of concomitant pressure and symptom analysis in response to a rapid drink challenge (RDC).

METHODS

In consecutive patients referred for esophageal manometry, a RDC consisting in free drinking of 200 ml of water as quick as possible was performed after the standard single water swallows manometry. Both pressure patterns and usual symptoms induced by the RDC were analyzed.

RESULTS

A total of 1319 patients were included, (64.7% women, mean age 58.2 years, range 11-90). There were significant differences in pressure responses between patients with obstructive disorders, major hypercontractile disorders, esophageal hypomotility disorders and normal motility. The RDC provoked usual symptoms in 388 (29.4%) patients, associated with hyperpressive and obstructive patterns in 14.0% and 16.6%, respectively. Reproduction of dysphagia and regurgitation (not pain) was significantly associated with abnormal pressure responses during the RDC (p < 0.001 and p = 0.002, respectively). The RDC elicited both abnormal pressure patterns and symptoms in 6.2%, 1.6%, and 20.8% of patients with normal motility, ineffective esophageal motility, and esophago-gastric junction outflow obstruction, respectively.

CONCLUSION

Concomitant evaluation of symptoms and pressure responses to a RDC may increase the specificity of esophageal motor testing in patients with inconclusive diagnosis or normal esophageal motility.

Assessment of the Multiple Rapid Swallows Test for Gauging Esophageal Reflux Burden in Patients with Refractory Gastroesophageal Reflux Disease

BACKGROUND The multiple rapid swallows (MRS) test is used to assess esophageal contraction reserve. In this study, we characterized the expression of the MRS test in patients with reflux burden and other symptomatic phenotypes with refractory gastroesophageal reflux disease (rGERD). MATERIAL AND METHODS Patients with rGERD who underwent high-resolution manometry (HRM) and esophageal pH-impedance monitoring (EIM) between September 2018 and January 2020 were retrospectively studied. RESULTS We enrolled 151 patients and divided them into 4 phenotypes according to the results of EIM. In phenotype 1, the MRS distal contractile integral (DCI) was significantly positively correlated with acid-liquid reflux episodes. In phenotype 2, lower esophageal sphincter pressure (LES) length was significantly positively correlated with MRS DCI, and MRS/single-swallow (SS) DCI ratio. In phenotype 3, MRS DCI was negatively correlated with the DeMeester score, acid exposure time (AET), upright AET, long-term acid reflux episodes, acid-mixed reflux episodes, recumbent acid reflux episodes, and total acid reflux episodes. There was a significant negative correlation between MRS/SS DCI and recumbent acid reflux episodes. In phenotype 4, nonacid-liquid episodes and recumbent nonacid reflux episodes were significantly higher in the abnormal MRS group. However, acid-gas episodes, weakly acid-gas episodes, and upright gas reflux episodes were higher in the normal MRS group than in the abnormal MRS group. CONCLUSIONS Esophageal contraction reserve is heterogeneous within the reflux burden and symptomatic phenotypes of patients with rGERD.

Evaluation of the Esophagogastric Junction on High Resolution Manometry

The esophagogastric junction (EGJ) is a complex barrier between the thoracic and abdominal luminal gut compartments, comprised primarily of the lower esophageal sphincter (LES) and crural diaphragm. Although closed at rest, the EGJ relaxes to allow antegrade bolus transit and retrograde venting of air. Abnormal relaxation is the hallmark of achalasia spectrum disorders, while increased frequency of transient lower esophageal sphincter relaxations and/or EGJ disruption are seen in gastroesophageal reflux disease. High resolution manometry (HRM) is the modern day gold standard for assessment of EGJ morphology and function, with better performance characteristics compared with endoscopy and barium esophagography. Conventional LES metrics defining EGJ function include resting LES pressure as well as postswallow residual pressures. Newer HRM-based metrics include EGJ contractile integral, which measures static barrier function at rest, and EGJ morphology, which characterizes the relationship between LES and crural diaphragm. Provocative maneuvers assess dynamic EGJ function during physiological or pharmacologic stress. The most useful of these maneuvers, the rapid drink challenge, assesses for latent obstruction, while multiple rapid swallows evaluate adequacy of deglutitive inhibition. Amyl nitrate and cholecystokinin administration can segregate motor from structural obstruction. Newer provocative tests (straight leg raise maneuver, abdominal compression) and novel diagnostic tools (functional lumen imaging probe) complement HRM evaluation of the EGJ. Although current HRM metrics and maneuvers show promise in identifying clinically relevant EGJ abnormalities, future investigations evaluating management outcomes will improve segregation of normal from abnormal EGJ morphology and function.

What is new in Chicago Classification version 4.0?

Since publication of Chicago Classification version 3.0 in 2015, the clinical and research applications of high-resolution manometry (HRM) have expanded. In order to update the Chicago Classification, an International HRM Working Group consisting of 52 diverse experts worked for two years and utilized formally validated methodologies. Compared with the prior iteration, there are four key modifications in Chicago Classification version 4.0 (CCv4.0). First, further manometric and non-manometric evaluation is required to arrive at a conclusive, actionable diagnosis of esophagogastric junction (EGJ) outflow obstruction (EGJOO). Second, EGJOO, distal esophageal spasm, and hypercontractile esophagus are three manometric patterns that must be accompanied by obstructive esophageal symptoms of dysphagia and/or non-cardiac chest pain to be considered clinically relevant. Third, the standardized manometric protocol should ideally include supine and upright positions as well as additional manometric maneuvers such as the multiple rapid swallows and rapid drink challenge. Solid test swallows, postprandial testing, and pharmacologic provocation can also be considered for particular conditions. Finally, the definition of ineffective esophageal motility is more stringent and now encompasses fragmented peristalsis. Hence, CCv4.0 no longer distinguishes between major versus minor motility disorders but simply separates disorders of EGJ outflow from disorders of peristalsis.

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.

Enhancing High-Resolution Esophageal Manometry: Use of Ancillary Techniques and Maneuvers

High-resolution manometry evaluates esophageal motor function using 10 supine water swallows. Superimposing impedance over high-resolution manometry pressure topography assesses the relationship between contraction and bolus propulsion and identifies inadequate clearance. Ancillary techniques and maneuvers augment the standard supine high-resolution manometry evaluation by challenging peristaltic function. Increasing bolus volume (rapid drink challenge) and altering bolus consistency (standardized test meal, solid swallows) enhance identification of esophageal outflow obstruction syndromes. Physiologic maneuvers (multiple rapid swallows, abdominal compression) address the ability of the esophageal smooth muscle to augment contraction vigor. Pharmacologic challenge is less commonly used clinically, and elucidates pathophysiology of esophageal motor disorders.

High-Resolution Manometry-Observations After 15 Years of Personal Use-Has Advancement Reached a Plateau?

PURPOSE OF REVIEW

In the absence of mucosal or structural disease, the aim of investigating the oesophagus is to provide clinically relevant measurements of function that can explain the cause of symptoms, identify pathology and guide effective management. One of the most notable recent advances in the field of oesophageal function has been high-resolution manometry (HRM). This review explores how innovation in HRM has progressed and has far from reached a plateau.

RECENT FINDINGS

HRM technology, methodology and utility continue to evolve; simple additions to the swallow protocol (e.g. eating and drinking), shifting position, targeting symptoms and adding impedance sensors to the HRM catheter have led to improved diagnoses, therapeutic decision-making and outcomes. Progress in HRM persists and shows little sign of abating. The next iteration of the Chicago Classification of motor disorders will highlight these advances and will also identify opportunities for further research and innovation.

Esophageal physiology-an overview of esophageal disorders from a pathophysiological point of view

The esophagus serves the principal purpose of transporting food from the pharynx into the stomach. A complex interplay between nerves and muscle fibers ensures that swallowing takes place as a finely coordinated event. Esophageal function can be tested by a variety of methods, endoscopy, manometry, and reflux monitoring being some of the most important. Regarding pathophysiology, motor disorders, such as achalasia, often cause dysphagia and/or chest pain. Functional esophageal disorders are a heterogeneous group with hypersensitivity as a dominant pathophysiological factor. Gastroesophageal reflux disease often causes symptoms, such as heartburn and regurgitation, and a spectrum of disease, ranging from minimal mucosal damage visible only in the microscope to esophageal ulcers and strictures in the most severe cases. Eosinophilic esophagitis is an immune-mediated condition that can result in significant dysphagia and associated luminal narrowing. In the following, we will provide an overview of the most common esophageal disorders from a combined pathophysiological and clinical view.

Trans-esophagogastric junction pressure gradients during straight leg raise maneuver on high-resolution manometry associate with large hiatus hernias

BACKGROUND

Straight leg raise (SLR) while supine increases intra-abdominal pressure. We hypothesized that elevations in intra-abdominal pressure would transmit into the thoracic cavity if the esophagogastric junction (EGJ) was disrupted.

METHODS

Consecutive patients undergoing esophageal HRM were included if they had adequate SLR (hip flexion with knees extended for ≥ 5 seconds while supine). EGJ morphology was subtyped based on lower esophageal sphincter (LES) and crural diaphragm (CD) location (type 1: LES and CD overlap; type 2: separation of < 3 cm; type 3: separation of ≥ 3 cm). EGJ tone was assessed using EGJ contractile integral (EGJ-CI). HRM studies were analyzed according to Chicago Classification v3.0. Mean and peak intra-thoracic and abdominal pressures were measured at baseline and during SLR using on-screen software tools. Trans-EGJ gradients were compared, and pressure gradient < 1 mmHg denoted the equalization of pressures.

KEY RESULTS

Of 430 patients, 248 (57.5 ± 0.9 years, 69.4% F) completed SLR. EGJ morphology was type 1 in 122 (49.2%), type 2 in 56 (22.6%) and type 3 in 40 (16.1%). In types 1 and 2 EGJ, neither the mean nor peak trans-EGJ pressure gradient changed with SLR (P ≥ .17 for each). In contrast, in type 3 EGJ, peak pressure gradient decreased significantly following SLR (3.5 ± 1.8 mmHg vs. -8.6 ± 4.8 mmHg, P = .01). More type 3 EGJ patients equalized peak (65%) pressures across EGJ compared with types 1 and 2 (27%, P < .001).

CONCLUSIONS AND INFERENCES

The evaluation of intra-abdominal and intra-thoracic pressures with SLR during esophageal HRM can provide evidence of physiological disruption of the EGJ barrier.

Prospective serial diagnostic study: the effects of position and provocative tests on the diagnosis of oesophageal motility disorders by high-resolution manometry

BACKGROUND

Standard high-resolution manometry (HRM) protocols are based on 10 single water swallows acquired in the supine position.

AIMS

To assess the impact of position, rapid drink challenge and solid test meal on the diagnosis of oesophageal motility disorders.

METHODS

Seventy-two healthy volunteers (20-76 years) and 366 consecutive patients (18-90 years) completed HRM with 10 single water swallows in the supine and upright positions. Rapid drink challenge was performed twice, before and after the solid test meal. Diagnosis based on single water swallows in the supine position (Chicago Classification v3.0) was compared with results in the upright position and with provocative tests.

RESULTS

Overall, diagnostic agreement in the supine and upright positions was present in 296/438 (67.6%) subjects. This increased to 90.0% when ineffective oesophageal motility was considered with normal motility. Integrated relaxation pressure was 4 mm Hg higher in the supine position. There was a higher prevalence of inconsistent, likely false positive, diagnoses of outlet obstruction in the supine compared to the upright position (16/20 vs 1/4 patients, P = 0.0007). Similarly, the difference in concordance for the diagnosis of oesophago-gastric junction obstruction or achalasia between single water swallows in the supine and upright positions with solid test meal was significant (12/29 (41.4%) vs 12/14 (85.7%), P = 0.0087).

CONCLUSION

Diagnostic agreement for oesophageal motility disorders based on single water swallows in the upright and supine positions was moderate, with frequent discordant findings for ineffective motility and outlet obstruction. HRM studies can be performed in either position, using appropriate reference values. Rapid drink challenge or solid test meal can resolve diagnostic discrepancies.

Changes in high-resolution manometric diagnosis over time: implications for clinical decision-making

Although High resolution esophageal manometry (HRM) is the gold standard to assess esophageal motility, little is known about the stability of the manometric diagnosis over time and its implications for management. To assess the stability and usefulness of repeat HRM in patients presenting with esophageal symptoms over time we performed this retrospective study of patients with esophageal symptoms. Medical records, questionnaires, and HRM tracing were independently reviewed using the Chicago classification. The primary objective was to assess the stability of the manometric diagnosis over time; secondary objective was its change (positive or negative). At least one repeat study was performed in 86 patients (36% women, ages 20-86, with mild to moderate symptoms), while 26 had a third procedure. Mean intervals between studies were 15 ± 1.6 months (for baseline v. first study) and 13 ± 0.8 months (for second to third study). Of the 27 patients initially with a normal study, 11 changed (five had esophago-gastric junction outflow obstruction [EGJOO], two diffuse esophageal spasm [DES], one jackhammer esophagus [JE], and three ineffective esophageal motility [IEM] [41% change]). Of the 24 patients with initial EGJOO, only nine retained it (65.2% change). Of nine patients with initial DES, four changed (44.4% change). Similarly, different diagnosis was seen in 7 of 24 initial IEM patients (22.7% change). Only one patient had achalasia initially and this remained stable. Additional changes were noted on a third HRM. Fluidity in the HRM diagnosis over time questions its validity at any timepoint and raises doubts about the need for intervention.

Neuronal Control of Esophageal Peristalsis and Its Role in Esophageal Disease

PURPOSE OF REVIEW

Esophageal peristalsis is a highly sophisticated function that involves the coordinated contraction and relaxation of striated and smooth muscles in a cephalocaudal fashion, under the control of central and peripheral neuronal mechanisms and a number of neurotransmitters. Esophageal peristalsis is determined by the balance of the intrinsic excitatory cholinergic, inhibitory nitrergic and post-inhibitory rebound excitatory output to the esophageal musculature.

RECENT FINDINGS

Dissociation of the longitudinal and circular muscle contractions characterizes different major esophageal disorders and leads to esophageal symptoms. Provocative testing during esophageal high-resolution manometry is commonly employed to assess esophageal body peristaltic reserve and underpin clinical diagnosis. Herein, we summarize the main factors that determine esophageal peristalsis and examine their role in major and minor esophageal motility disorders and eosinophilic esophagitis.

Ineffective esophageal motility: Concepts, future directions, and conclusions from the Stanford 2018 symposium

BACKGROUND

Ineffective esophageal motility (IEM) is a heterogenous minor motility disorder diagnosed when ≥50% ineffective peristaltic sequences (distal contractile integral <450 mm Hg cm s) coexist with normal lower esophageal sphincter relaxation (integrated relaxation pressure < upper limit of normal) on esophageal high-resolution manometry (HRM). Ineffective esophageal motility is not consistently related to disease states or symptoms and may be seen in asymptomatic healthy individuals.

PURPOSE

A 1-day symposium of esophageal experts reviewed existing literature on IEM, and this review represents the conclusions from the symposium. Severe IEM (>70% ineffective sequences) is associated with higher esophageal reflux burden, particularly while supine, but milder variants do not progress over time or consistently impact quality of life. Ineffective esophageal motility can be further characterized using provocative maneuvers during HRM, especially multiple rapid swallows, where augmentation of smooth muscle contraction defines contraction reserve. The presence of contraction reserve may predict better prognosis, lesser reflux burden and confidence in a standard fundoplication for surgical management of reflux. Other provocative maneuvers (solid swallows, standardized test meal, rapid drink challenge) are useful to characterize bolus transit in IEM. No effective pharmacotherapy exists, and current managements target symptoms and concurrent reflux. Novel testing modalities (baseline and mucosal impedance, functional lumen imaging probe) show promise in elucidating pathophysiology and stratifying IEM phenotypes. Specific prokinetic agents targeting esophageal smooth muscle need to be developed for precision management.

Achalasia diagnosed despite normal integrated relaxation pressure responds favorably to therapy

BACKGROUND

Achalasia diagnosis requires elevated integrated relaxation pressure (IRP; manometric marker of lower esophageal sphincter [LES] relaxation). Yet, some patients exhibit clinical features of achalasia despite normal IRP and have LES dysfunction demonstrable by other means. We hypothesized these patients to exhibit equivalent therapeutic response compared to standard achalasia patients.

METHODS

Symptomatic achalasia-like cases, despite normal IRP, displayed evidence of impaired LES relaxation using rapid drink challenge (RDC), solid swallows during high-resolution manometry, and/or barium esophagogram; were treated with achalasia therapies and compared to standard achalasia patients with raised IRP. Outcomes included equivalence for short- and long-term symptom response and stasis on barium esophagogram.

KEY RESULTS

Twenty-nine normal IRP achalasia cases (14 males, median age 50 year, median Eckardt 6, barium stasis 12 ± 7 cm) and 29 consecutive standard achalasia controls underwent therapy. Among cases, LES dysfunction was most often identified by RDC and/or barium esophagogram. Short-term symptomatic success was equivalent in cases vs controls (90% vs 93%; 95% CI for difference: -19% to 13%). Median short-term (1 vs 1; 95% CI for difference: 0-1) and long-term Eckardt scores (2 vs 1; 95% CI for difference: 0-2) were similar in cases and controls, respectively. Adequate clearance was observed in 67% of cases vs 81% of controls on post-therapy esophagogram.

CONCLUSIONS AND INFERENCES

We described a subset of achalasia patients with normal IRP, but impaired LES relaxation identifiable only on additional provocative tests. These patients benefited from treatment, suggesting that such tests should be performed to increase the number of clinically relevant diagnoses.

Evaluation of Esophageal Contraction Reserve Using HRM in Symptomatic Esophageal Disease

Esophageal high resolution manometry (HRM) is the gold standard for assessment of esophageal motor disorders, but motor responses to the standard 5 mL water swallow protocol may not provide precision in defining minor motor disorders. Provocative maneuvers, particularly multiple rapid swallows (MRS), have been used to assess deglutitive inhibition during the repetitive swallows, and the contractile response following the final swallow of the sequence. The augmentation of esophageal smooth muscle contraction following MRS is termed contraction reserve. This is determined as the ratio between esophageal body contraction vigor (distal contractile integral, DCI) following MRS to the mean DCI after single swallows, which is ≥1 in the presence of contraction reserve. Reliable assessment of contraction reserve requires the performance of 3 MRS maneuvers during HRM. Absence of contraction reserve is associated with a higher likelihood of late postfundoplication dysphagia and may correlate with higher esophageal reflux burden on ambulatory reflux monitoring. Esophageal motor responses to abdominal compression, functional lumen imaging probe (FLIP) balloon distension, and pharmacologic testing (using edrophonium and cisapride) may correlate with contraction reserve. Other provocative tests useful during HRM include rapid drink challenge, solid and viscous swallows, and standardized test meals, which are more useful in evaluation of esophageal outflow obstruction and dysphagia syndromes than in identification of contraction reserve. Provocative maneuvers have been recommended as part of routine HRM protocols, and while useful clinical information can be gleaned from these maneuvers, further research is necessary to determine the precise role of provocative testing in clinical esophagology.

Clinical Management of Pediatric Achalasia: A Survey of Current Practice

OBJECTIVES

Pediatric achalasia is a rare neurodegenerative disorder of the esophagus that requires treatment. Different diagnostic and treatment modalities are available, but there are no data that show how children can best be diagnosed and treated. We aimed to identify current practices regarding the diagnostic and therapeutic approach toward children with achalasia.

METHODS

Information on the current practice regarding the management of pediatric achalasia was collected by an online-based survey sent to members of the European and North American Societies for Pediatric Gastroenterology Hepatology and Nutrition involved in pediatric achalasia care.

RESULTS

The survey was completed by 38 centers from 24 countries. Within these centers, 108 children were diagnosed with achalasia in the last year (median 2, range 0-15). Achalasia was primarily managed by a pediatric gastroenterologist (76%) and involved a multidisciplinary team in 84% of centers, also including a surgeon (87%), radiologist (61%), dietician (37%), speech pathologist (8%), and psychologist (5%). Medical history taking and physical examination were considered most important to establish the diagnosis (50%), followed by (a combination of) manometry (45%) or contrast swallow (21%). Treatment of first choice was Heller myotomy (58%), followed by pneumatic dilation (46%) and peroral endoscopic myotomy (29%).

CONCLUSION

This study shows a great heterogeneity in the management of pediatric achalasia amongst different centers worldwide. These findings stress the need for well-designed intervention trials in children with achalasia. Given the rarity of this disease, we recommend that achalasia care should be managed in centers with access to appropriate diagnostic and treatment modalities.

Chicago Classification normative metrics in a healthy Indian cohort for a 16-channel water-perfused high-resolution esophageal manometry system

BACKGROUND

High-resolution esophageal manometry (HREM) interpretation by the Chicago Classification (CC) derives its normal values from western volunteers using solid-state catheters. There is no normative data for the 16-channel water-perfused HREM system commonly used in India.

AIMS

To determine normal values for a 16-channel water-perfused HREM catheter in supine posture using healthy volunteers and substitute these normal values (if different from CC values) in the CC v3.0 algorithm.

METHODS

After ethics approval and informed consent, 53 volunteers (31 men) with no gastrointestinal (GI) symptoms or medications affecting GI motility underwent HREM by standard protocol. Age, gender, body mass index (BMI), and manometry parameters analyzed using Trace 1.3.3 software were collected. The median, range, and 5, 10, 75, and 95 percentiles (where applicable) were obtained for all HREM metrics. Normal value percentiles were defined as 95th (integrated relaxation pressure [IRP]), 10th-100th (distal contractile integral [DCI]), and minimum (distal latency [DL]).

RESULTS

The mean age was 30 years and the BMI was 24.2 kg m^-2 . Compared to CC, our normal metrics were lower for IRP (13 mm Hg) and DCI (350-4500 mm Hg s cm). DCI >4500 and <70 (<5th percentile) were defined as hypercontractile and failed contraction, respectively. Abnormal DL (<4.5 s) and peristaltic break size (>5 cm) were similar to CC metrics. Applying these metrics, CC diagnoses changed in 15% (8/53) with downgrading of ineffective motility to fragmented peristalsis or normal, due to lower DCI cutoff used.

CONCLUSIONS

This is the first report of normative data for the 16-channel water-perfused system in supine posture. It revealed lower IRP and DCI, necessitating modification of CC cutoffs for this system.

The role of oesophageal physiological testing in the assessment of noncardiac chest pain

Oesophageal physiology testing plays an important role in the diagnosis of noncardiac chest pain (NCCP) after cardiac, structural and mucosal abnormalities have been ruled out. Endoscopy can establish the presence of structural causes of chest pain such as cancer, oesophageal webs and diverticula. Even if macroscopically normal, eosinophilic oesophagitis is a common cause of chest pain and needs to be ruled out with an adequate biopsy regimen. In the remaining cases, diagnosis is focused on the identification of often subtle mechanisms that lead to NCCP. The most common oesophageal aetiologies for NCCP are gastro-oesophageal reflux disease (GORD), oesophageal dysmotility and functional chest pain. Ambulatory pH studies (with or without impedance or wireless measurements) can establish the presence of GORD, nonerosive reflux as well any association with symptoms of chest pain. High-resolution manometry, particularly with the inclusion of adjunctive testing, can rule out major motility disorders such as spasm, hypercontraction or achalasia. The EndoFLIP device can help define disorders with reduced distensibility, not easily appreciated with endoscopy or manometry. When all tests remain negative, a diagnosis of oesophageal hypersensitivity is normally made and therapy is shifted from targeting a disease to treating symptoms and patient affect.

Esophageal provocation tests: Are they useful to improve diagnostic yield of high resolution manometry?

High resolution manometry (HRM) is the gold standard to diagnose esophageal motility disorders but has some limitations. The inclusion of provocative tests might enhance the diagnostic yield of HRM. These tests are easy to perform and to add to the regular manometry protocol. Multiple rapid swallows (MRS; 5 2-mL swallows) is useful to assess the contractile reserve and deglutitive inhibition. The optimal number of MRS to perform might be 3 as suggested by Mauro et al. in this issue of Neurogastroenterology & Motility. The absence of contractile reserve might be associated with gastro-esophageal reflux disease and with an increased risk of post fundoplication dysphagia. Single viscous and solid swallows might enhance the detection of esophageal motility disorders but are not significantly associated with symptom occurrence. Test meal has the advantage to represent a real-life scenario and is promising to depict significant motility findings responsible for esophageal symptoms. Post-prandial recording might also be of interest to diagnose rumination and belching disorders. The best indication of rapid drink challenge test (free drinking of 200 mL) is currently the diagnosis of esophago-gastric junction obstruction. Finally, abdominal compression might be an option to evaluate response of esophageal peristalsis in a context of outflow resistance as proposed by Brink et al. in this issue. These provocative maneuvers appear to provide a complementary role in the evaluation of esophageal motility but require prospective studies to determine the validity of the findings and whether they will lead to changes in clinical practice.