Normative values in esophageal high-resolution manometry

Diagnostic Utility of High-resolution Esophageal Manometry and Its Correlation with Symptoms

BACKGROUND

Primary esophageal motility disorders present with a spectrum of symptoms where manometry plays an important role. We designed this study to evaluate the utility of esophageal manometry among various symptoms.

MATERIALS AND METHODS

This is a single-center observational study conducted over 5 years in a tertiary referral center. A total of 564 patients who underwent high-resolution esophageal manometry (HREM) using a 16-channel water perfusion system were included in the study. Their clinical profile and manometric findings, as per the Chicago classification version 4.0, were recorded, and the diagnostic utility of HREM with respect to symptoms was studied.

RESULTS

Motility disorders were identified in 48.8% of patients, the most common being Achalasia cardia (32.4%). Dysphagia (55.5%) was the most common indication of manometry, followed by gastroesophageal reflux disease (GERD) (34.9%), chest pain (6.2%), and symptoms such as belching, globus, and hiccoughs (3.4%). Among those who were re-classified from Chicago classification v3.0 to v4.0, 21.2% had a newer diagnosis. Among the patients with dysphagia, HREM revealed the highest yield of detecting an abnormal esophageal motility test (70.6%); meanwhile, this yield was much lower in those with GERD (21.8%), chest pain (22.8%), and other symptoms (15.7%). The most common finding among those with dysphagia was Achalasia cardia (55.9%), while the study was normal among those with GERD (78.1%), chest pain (77.1%), and other symptoms (84.2%). The sensitivity and specificity of dysphagia for major motility disorders were 65% and 91%, respectively, with a positive predictive value of 90%.

CONCLUSION

HREM has high accuracy and a good diagnostic yield among patients with dysphagia, with the most common finding being Achalasia cardia.

Normative high resolution esophageal manometry values in asymptomatic patients with obesity

BACKGROUND

Surgical bariatric interventions, while highly effective, can be associated with post-operative esophageal symptoms, gastroesophageal reflux disease and esophageal dysmotility. Whether pre-operative physiology impacts this risk is unknown, in part because expected values on esophageal manometry in patients with obesity are not well understood. This study seeks to establish normative values on esophageal high resolution manometry (HRM) and the prevalence of esophageal dysmotility in the asymptomatic patient with obesity.

METHODS

This retrospective study included adult patients with body mass index (BMI) ≥35 kg m-2 without esophageal symptoms undergoing preoperative bariatric surgical evaluation, including HRM, at a single tertiary care center between February, 2019 and February, 2020.

RESULTS

Of 104 asymptomatic patients with obesity, HRM identified normal esophageal motility in 94 (90.4%) with the remaining 10 having ineffective esophageal motility (3.8%), manometric esophagogastric junction outflow obstruction (3.8%), distal esophageal spasm (1.0%), and hypercontractile esophagus (1.0%). Mean of median lower esophageal sphincter integrated relaxation pressure (LES IRP) was 10.6 mmHg supine (95th percentile 21.5 mmHg) and 8.5 mmHg upright (95th percentile 21.3 mmHg). 86% of patients had intragastric pressure above 8 mmHg. Mean of mean distal contractile integral (DCI) was 2261.6 mmHg cm s-1 (95th percentile 5889.5 mmHg cm s-1).

CONCLUSION

The vast majority of asymptomatic patients with obesity had normal manometry. LES IRP and DCI were higher than that observed in non-obese cohorts. Additionally, BMI correlated to increased intragastric pressure. These data suggest that normative values in patients with obesity should be adjusted to prevent overdiagnosis of EGJOO or hypercontractile esophagus.

Esophageal motor disorders across ages: A retrospective multicentric analysis

BACKGROUND

Age-related changes in the gastrointestinal system are common and may be influenced by physiological aging processes. To date, a comprehensive analysis of esophageal motor disorders in patients belonging to various age groups has not been adequately reported.

METHODS

We conducted a retrospective assessment of high-resolution manometry (HRM) studies in a multicenter setting. HRM parameters were evaluated according to the Chicago Classification version 4.0. Epidemiological, demographic, clinical data, and main manometric parameters, were collected at the time of the examination. Age groups were categorized as early adulthood (<35 years), early middle-age (35-49 years), late middle-age (50-64 years), and late adulthood (≥65 years).

RESULTS

Overall, 1341 patients (632, 47.0% male) were included with a median age of 55 years. Late adulthood patients reported more frequently dysphagia (35.2%) than early adulthood patients (24.0%, p = 0.035), early middle-age patients (21.0%, p < 0.0001), and late middle-aged patients (22.7%, p < 0.0001). Esophagogastric junction outflow obstruction was more prevalent in late adulthood (16.7%) than in early adulthood (6.1%, p = 0.003), and in early middle-age (8.1%, p = 0.001). Patients with normal esophageal motility were significantly younger (52.0 years) than patients with hypercontractile esophagus (61.5 years), type III achalasia (59.6 years), esophagogastric junction outflow obstruction (59.4 years), absent contractility (57.2 years), and distal esophageal spasm (57.0 years), in multivariate model (p < 0.0001).

CONCLUSION

The rate of esophageal motor disorders is higher in older patients, in particular esophagogastric junction outflow obstruction and hypercontractile esophagus. Future prospective studies are necessary to confirm our results and to find tailored strategies to improve clinical outcomes.

Integrated Relaxation Pressure and Its Diagnostic Ability May Vary According to the Conditions Used for HREM Recording

Integrated Residual Pressure (IRP) measured under conditions alternative to supine single swallows may provide clinically useful information regarding EGJ relaxation. This study aimed to compare IRP values obtained under different situations and explore their potential clinical utility. We analyzed and compared the values of IRP obtained from healthy volunteers and patients with suspected achalasia during supine single swallows (Ssup-IRP), sitting single swallows (Ssit-IRP), supine multiple rapid swallows (Msup-IRP), and sitting multiple rapid swallows (Msit-IRP). We analyzed the HREM recordings of 40 healthy volunteers and 53 patients with suspected achalasia. The four metrics were significantly different from each other in healthy volunteers (Ssup-IRP > Msup-IRP > Ssit-IRP > Msit-IRP) and their corresponding 95th percentiles were substantially distinct (Ssup-IRP: 25.3 mmHg, Ssit-IRP: 20.9 mmHg, Msup-IRP: 15.9 mmHg, and Msit-IRP: 11.9 mm Hg, respectively). Complete agreement among the four metrics in predicting abnormal IRP was found in 39 of the 47 patients with suspected achalasia who completed the protocol. Optimal cutoffs derived from ROC curve analysis demonstrated ≥ 0.95 specificities for detection of impaired EGJ relaxation among patients with suspected achalasia. Among the eight patients with suspected achalasia with normal Ssup-IRP, five demonstrated abnormal Msit-IRP and four abnormal Ssit-IRP. Significant differences of IRP exist depending on the measurement situation, indicating that correct interpretation of IRP values requires specific cutoffs for each situation.The sensitivities of Ssit-IRP and Msit-IRP in detecting defective EGJ relaxation appear to be slightly higher than that of Ssup-IRP.

Defining "true acid reflux" after peroral endoscopic myotomy for achalasia: a prospective cohort study

BACKGROUND AND AIMS

The symptoms of reflux in achalasia patients undergoing peroral endoscopic myotomy (POEM) are believed to result from gastroesophageal reflux, and the current treatment primarily focuses on acid suppression. Nevertheless, other factors such as nonreflux acidification caused by fermentation or stasis might play a role. This study aimed to identify patients with "true acid reflux" who actually require acid suppression and fundoplication.

METHODS

In this prospective large cohort study, the primary objective was to assess the incidence and risk factors for true acid reflux in achalasia patients undergoing POEM. Acid reflux with normal and delayed clearance defined true acid reflux, whereas other patterns were labeled as nonreflux acidification patterns on manual analysis of pH tracings. These findings were corroborated with a symptom questionnaire, esophagogastroscopy, esophageal manometry, and timed barium esophagogram at 3 months after the POEM procedure.

RESULTS

Fifty-four achalasia patients aged 18 to 80 years (mean age, 41.1 ± 12.8 years; 59.3% men; 90.7% with type II achalasia) underwent POEM, which resulted in a significant mean Eckardt score improvement (6.7 to 1.6, P < .05). True acid reflux was noted in 29.6% of patients as compared with 64.8% on automated analysis. Acid fermentation was the predominant acidification pattern seen in 42.7% of patients. On multivariable logistic regression analysis, increasing age (odds ratio, 1.12; 95% confidence interval, 1.02-1.27; P = .04) and preprocedural integrated relaxation pressure (IRP; odds ratio, 1.13; 95% confidence interval, 1.04-1.30; P = .02) were significantly associated with true acid reflux in patients after undergoing POEM.

CONCLUSIONS

A manual review of pH tracings helps to identify true acid reflux in patients with achalasia after undergoing POEM. Preprocedural IRP can be a predictive factor in determining patients at risk for this outcome. (Clinical trial registration number: NCT04951739.).

Contraction reserve in high resolution manometry is correlated with lower esophageal acid exposure time in patients with normal esophageal motility: A retrospective observational study

BACKGROUND

In high resolution manometry (HRM), distal contractile integral post multiple rapid swallow augmentation is considered as contraction reserve. The relationship between contraction reserve and esophageal acid reflux remains unclear. The aim of this study was to explore the correlation between contraction reserve and esophageal acid exposure in ineffective esophageal motility (IEM) and normal HRM.

METHODS

Patients who underwent HRM and ambulatory reflux monitoring were retrospectively screened. Those with diagnosis of normal HRM or IEM were included in the analysis. The proportion of patients with abnormal acid exposure time (AET) was compared between patients with and without contraction reserve. Multivariate regression analysis was performed to determine the predictors of abnormal AET and contraction reserve.

RESULTS

A total of 338 patients, including 264 normal HRM and 74 IEM, were included in the analysis. In patients with normal HRM, proportion of abnormal total AET (AET > 6.0%) was significantly lower in patients with supine contraction reserve than patients without contraction reserve (13.85% vs. 24.63%, p = 0.027). Multivariate regression analysis showed that supine contraction reserve could independently predict abnormal total AET (OR = 0.468, 95% CI: 0.249-0.948, p = 0.034), while upright contraction reserve trended strongly (OR = 0.558, 95% CI: 0.290-1.071, p = 0.079). Subgroup analysis showed that upright contraction reserve was an independent predictor of abnormal total AET in patients with 50-70% infective swallows (OR = 0.205, 95% CI: 0.051-0.821, p = 0.025), whereas supine contraction reserve did not have predictive value (p = 0.359).

CONCLUSIONS

Supine contraction reserve correlates with esophageal acid reflux in patients with normal HRM, while only upright contraction reserve correlates with esophageal acid reflux in patients with infective swallows of 50-70%.

[Diagnosis of esophageal motility disorders - Significance of the new Chicago classification v4.0]

Esophageal motility disorders are diseases in which there are malfunctions of the act of swallowing due to a change in neuromuscular structures. The main symptom is therefore dysphagia for solid and/or liquid foods, often accompanied by symptoms such as chest pain, regurgitation, heartburn, and weight loss. Esophageal manometry is the gold standard in diagnostics. Endoscopy and radiology serve to exclude inflammatory or malignant changes. With the introduction of high-resolution esophageal manometry (HRM), the diagnosis of esophageal motility disorders has improved and led to a new classification with the Chicago Classification, which has been modified several times in the last decade, most recently in 2021 with the Chicago Classification v4.0. Compared to the previous version 3.0, there are some important changes that are presented based on the most important esophageal motility disorders in everyday clinical practice.

High-resolution impedance manometry for comparing bolus transit between patients with non-obstructive dysphagia and asymptomatic controls

BACKGROUND

Currently, there are no high-resolution impedance manometry (HRIM)-based diagnostic criteria for non-obstructive dysphagia (NOD). New impedance parameters, such as the esophageal impedance integral (EII) and volume of inverted impedance (VII) ratios, have shown strong correlations with bolus transit. This study compared the EII and VII ratios as diagnostic tools for NOD.

METHODS

We analyzed 36 participants (12 patients with achalasia, 12 patients with NOD [7 with normal motility and 5 with ineffective esophageal motility], and 12 asymptomatic controls) who underwent HRIM with a maximum of 5 swallows per participant. The EII and VII ratios were calculated as Z2 (post-swallow)/Z1 (pre-swallow). Bolus transit was retrospectively evaluated using transluminal impedance analysis.

KEY RESULTS

Both EII and VII ratios could effectively distinguish the achalasia group from the non-achalasia groups (area under the receiver operating characteristic curve [AUROC]: 0.83 for VII vs. 0.80 for EII; p = 0.73). However, the VII ratio was significantly better in discriminating asymptomatic controls from patients with dysphagia (NOD + achalasia) (AUROC: 0.81 vs. 0.68; p = 0.01). Moreover, the VII ratio was better in discriminating asymptomatic controls from patients with NOD (AUROC: 0.68 vs. 0.51; p = 0.06). In repeated swallows, the VII ratio was consistently the lowest in controls and the highest in patients with achalasia, whereas the EII ratio did not show a consistent pattern.

CONCLUSIONS & INFERENCES

The VII ratio was more reliable than the EII ratio for describing bolus transit and distinguishing patients with NOD from asymptomatic controls, even during repeated measures of subsequent swallows.

[Diagnosis of esophageal motility disorders - Significance of the new Chicago classification v4.0]

Esophageal motility disorders are diseases in which there are malfunctions of the act of swallowing due to a change in neuromuscular structures. The main symptom is therefore dysphagia for solid and/or liquid foods, often accompanied by symptoms such as chest pain, regurgitation, heartburn, and weight loss. Esophageal manometry is the gold standard in diagnostics. Endoscopy and radiology serve to exclude inflammatory or malignant changes. With the introduction of high-resolution esophageal manometry (HRM), the diagnosis of esophageal motility disorders has improved and led to a new classification with the Chicago Classification, which has been modified several times in the last decade, most recently in 2021 with the Chicago Classification v4.0. Compared to the previous version 3.0, there are some important changes that are presented based on the most important esophageal motility disorders in everyday clinical practice.

Esophageal Motility Disorders: Current Approach to Diagnostics and Therapeutics

Dysphagia is a common symptom with significant impact on quality of life. Our diagnostic armamentarium was primarily limited to endoscopy and barium esophagram until the advent of manometric techniques in the 1970s, which provided the first reliable tool for assessment of esophageal motor function. Since that time, significant advances have been made over the last 3 decades in our understanding of various esophageal motility disorders due to improvement in diagnostics with high-resolution esophageal manometry. High-resolution esophageal manometry has improved the sensitivity for detecting achalasia and has also enhanced our understanding of spastic and hypomotility disorders of the esophageal body. In this review, we discuss the current approach to diagnosis and therapeutics of various esophageal motility disorders.

Characteristics of high-resolution esophageal manometry in children without dysphagia

BACKGROUND

The absence of high-resolution esophageal manometry (HREM) norms in pediatrics limits the assessment of children with dysphagia. This study aimed to describe HREM parameters in a cohort of children without dysphagia.

METHODS

Children ages 9-16 years with a negative Mayo Dysphagia Questionnaire screen and normal histologic findings underwent HREM after completion of esophagogastroduodenoscopy. Ten swallows of 5 ml 0.45% saline boluses per subject were captured in supine position. Analyzed data included resting and integrated relaxation pressures (IRP) of lower (LES) and upper (UES) esophageal sphincters, peristaltic contractile integrals, transition zone (TZ) breaks, velocities, and lengths associated with proximal and distal esophagus.

KEY RESULTS

33 subjects (15 female) with mean (range) age 12.9 (9-16) years completed the study. Two of 330 analyzed swallows failed. The UES mean resting pressure, and its 0.2 s and 0.8 s IRPs were 48.3 (95% CI 12.9) mmHg, 2.9 (95% CI 1.9) mmHg, and 12.1 (95% CI 2.5) mmHg, respectively. The LES mean resting pressure and its 4 s IRP were 29.0 (95% CI 4.0) mmHg and 9.2 (95% CI 1.3) mmHg. The mean proximal (PCI) and distal (DCI) esophageal contractile integrals were 231 (95% CI 54.8) mmHg-s-cm and 1789.3 (95% CI 323.5) mmHg-s-cm, with mean TZ break 0.5 (95% CI 0.3) cm.

CONCLUSIONS & INFERENCES

This is the first study to describe HREM parameters in children without dysphagia. Most of the reported measurements were significantly different and less variable from reported adult norms. This emphasizes the need for child-specific catheters, norms, and protocols to define pediatric esophageal motility disorders.

Analysis of contractile segment impedance during straight leg raise maneuver using high-resolution impedance manometry increases diagnostic yield in reflux disease

BACKGROUND

Contractile segment impedance (CSI) obtained from high-resolution impedance manometry (HRIM) is a measure of mucosal integrity that predicts gastroesophageal reflux disease (GERD). While straight leg raise (SLR) maneuver augments esophageal peristaltic vigor, it remains unclear whether SLR affects CSI values. This study was aimed to evaluate whether CSI with SLR is feasible and useful to complement the diagnosis of GERD.

METHODS

We prospectively recruited 48 patients with typical GERD symptoms who underwent esophagogastroduodenoscopy, HRIM with SLR maneuver, and multichannel intraluminal impedance-pH (MII-pH) testing. The capability of mean nocturnal baseline impedance (MNBI), resting baseline impedance (RBI), CSI with or without SLR maneuver in predicting GERD was assessed using receiver operating characteristics (ROC) analysis.

KEY RESULTS

Among 20 GERD patients and 28 non-GERD patients, all values of impedance-based metrics were lower in GERD patients compared to non-GERD patients (p < 0.001). For GERD identification, area under receiver operating characteristic curve (AUROC) values of CSI with SLR maneuver, CSI, MNBI, and RBI were 0.901, 0.858, 0.865, and 0.797. Particularly in ineffective esophageal motility (IEM) patients, SLR maneuver increased mean distal contractile integral from 436 to 828.7 mmHg.s.cm (p = 0.018) and enhanced AUROC values of CSI for GERD identification from 0.917 to 0.958.

CONCLUSIONS & INFERENCES

CSI measurement during HRIM appears to be a reliable, time-saving, and less invasive tool for complementing GERD diagnosis. Our results also suggest a simple SLR maneuver during HRIM could enhance diagnostic accuracy of CSI for GERD identification especially in IEM patients.

Achalasia: Diagnosis, Management and Surveillance

Achalasia is a rare chronic esophageal motility disorder characterized by incomplete relaxation of the lower esophageal sphincter and abnormal peristalsis. This abnormal motor function leads to impaired bolus emptying and symptoms of dysphagia, regurgitation, chest pain, or heartburn. After an upper endoscopy to exclude structural causes of symptoms, the gold standard for diagnosis is high-resolution esophageal manometry. However, complementary diagnostic tools include barium esophagram and functional luminal impedance planimetry. Definitive treatments include pneumatic dilation, Heller myotomy with fundoplication, and peroral endoscopic myotomy.

Guidance on performance and reporting of high-resolution oesophageal manometry and ambulatory pH monitoring in Singapore

INTRODUCTION

We aimed to provide a practical and evidence-based guide on the indications, performance and reporting of high-resolution oesophageal manometry (HRM) and ambulatory pH monitoring (PHM) in adult patients in Singapore.

METHODS

The guideline committee comprised local gastroenterologists from public and private sectors with particular expertise in aspects of HRM and PHM, and it was tasked to produce evidence-based statements on the indications, performance and reporting of these tests. Each committee member performed literature searches to retrieve relevant articles within the context of domains to which they were assigned.

RESULTS

Twelve recommendation statements were created and summarised.

CONCLUSION

Standardising key aspects of HRM and PHM is imperative to ensure the delivery of high-quality care. We reported the development of recommendations for the performance and interpretation of HRM and ambulatory reflux monitoring in Singapore.

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.

Normal Values of High-resolution Manometry Parameters With Provocative Maneuvers

Background/Aims

Incorporation of complementary and provocative test swallows to the high-resolution manometry (HRM) protocol offers potential to address limitations posed by HRM protocols that involve only a single swallow type. The aim of this study is to describe normal findings of a comprehensive HRM testing protocol performed on healthy asymptomatic volunteers.

Methods

Thirty healthy asymptomatic volunteers completed HRM with 5-mL liquid swallows in the supine position. They also completed 5-mL liquid swallows in the upright position, viscous swallows, solid test swallows, multiple rapid swallows, and a rapid drink challenge. HRM studies were analyzed via Chicago classification version 3.0.

Results

The median (5th-95th percentiles) for integrated relaxation pressure (IRP) on supine swallows was 11 (4-16) mmHg; IRP was lower than supine on upright liquid 9 (0-17) mmHg, viscous 6 (0-15) mmHg, solid 9 (1-19) mmHg, multiple rapid swallows 3 (0-12) mmHg, and rapid drink challenge 5 (–3-12) mmHg; P < 0.005. While an “elevated” IRP value was observed on 1 to 2 test maneuvers in 8/30 (27%) subjects, all 30 subjects had an IRP value < 12 mmHg on at least one of the test maneuvers.

Conclusions

Normal values and findings from a comprehensive HRM testing protocol are reported based on evaluation of 30 healthy asymptomatic volunteers. Isolated “abnormalities” of IRP and contractile parameters were observed in the majority (80%) of these asymptomatic subjects, while all subjects also had normal features observed. Thus, the definition of “normal” should be recalibrated to focus on the entirety of the study and not individual metrics.

The effects of different postures and provocative swallow materials on the normative Chicago 3.0 metrics in a healthy Asian population

BACKGROUND AND AIM

Variations in the Chicago 3.0 normative metrics may exist with different postures and with different provocative swallow materials in a healthy Asian population.

METHOD

Eligible healthy Malay volunteers were invited to undergo the high-resolution esophageal manometry (inSIGHT Ultima, Diversatek Healthcare, Milwaukee, WI, USA). In recumbent and standing positions, test swallows were performed using liquid, viscous, and solid materials. Metrics including integrated relaxation pressure 4 s (IRP-4 s, mmHg), distal contractile integral (DCI, mmHg s cm), distal latency (DL, s), and peristaltic break (PB, cm) were reported in median and 95th percentile.

RESULTS

Fifty of 57 screened participants were recruited, and 586 saline, 265 viscous, and 261 solid swallows were analyzed. Per-patient wise, in the recumbent position, 95th percentile for IRP-4 s, DCI, DL, and PB were 16.5 mmHg, 2431 mmHg s cm, 8.5 s, and 7.2 cm, respectively. We observed that with each posture, the use of viscous swallows led to changes in DL, but the use of solid swallows led to more changes in the metrics including DCI and length of PB. Compared with a recumbent posture, anupright posture led to lower IRP-4 s and DCI values. Both per-patient analysis and per-swallow analyses yielded almost similar results when comparing the different postures and types of swallows. No major motility disorders were observed in this cohort of asymptomatic population. However, more motility disorders were reported in the upright position.

CONCLUSIONS

Variations in metrics can be observed in different postures and with different provocative swallow materials in a healthy population. The normative Chicago 3.0 metrics are also determined for the Malay population.

European Society for Neurogastroenterology and Motility (ESNM) recommendations for the use of high-resolution manometry of the esophagus

BACKGROUND

Several patients in gastroenterology practice present with esophageal symptoms, and in case of normal endoscopy with biopsies, high-resolution manometry (HRM) is often the next step. Our aim was to develop a European consensus on the clinical application of esophageal HRM, to offer the clinician guidance in selecting patients for HRM and using its results to optimize clinical outcome.

METHODS

A Delphi consensus was initiated with 38 multidisciplinary experts from 16 European countries who conducted a literature summary and voting process on 71 statements. Quality of evidence was evaluated using grading of recommendations assessment, development, and evaluation (GRADE) criteria. Consensus (defined as >80% agreement) was reached for 33 statements.

RESULTS

The process generated guidance on when to consider esophageal HRM, how to perform it, and how to generate the report. The Delphi process also identified several areas of uncertainty, such as the choice of catheters, the duration of fasting and the position in which HRM is performed, but recommended to perform at least 10 5-ml swallows in supine position for each study. Postprandial combined HRM impedance is considered useful for diagnosing rumination. There is a large lack of consensus on treatment implications of HRM findings, which is probably the single area requiring future targeted research.

CONCLUSIONS AND INFERENCES

A multinational and multidisciplinary group of European experts summarized the current state of consensus on technical aspects, indications, performance, analysis, diagnosis, and therapeutic implications of esophageal HRM.

[Diagnosis of Dysphagia: High Resolution Manometry & EndoFLIP]

Esophageal motility disorders were re-defined when high-resolution manometry was employed to better understand their pathogenesis. Newly developed parameters including integrated relaxation pressure (IRP), distal contractile integral, and distal latency showed better diagnostic yield compared with previously used conventional parameters. Therefore, Chicago classification was formulated, and its diagnostic cascade begins by assessing the IRP value. However, IRP showed limitation due to its inconsistency, and other studies have tried to overcome this. Recent studies showed that provocative tests, supplementing the conventional esophageal manometry protocol, have improved the diagnostic yield of the esophageal motility disorders. Therefore, position change from supine to upright, solid or semi-solid swallowing, multiple rapid swallows, and the rapid drink challenge were newly added to the manometry protocol in the revised Chicago classification version 4.0. Impedance planimetry enables measurement of bag cross-sectional area at various locations. The functional lumen imaging probe (FLIP) has been applied to assess luminal distensibility. This probe can also measure pressure, serial cross-sectional areas, and tension-strain relationship. The esophagogastric junction's distensibility is decreased in achalasia. Therefore, EndoFLIP can be used to assess contractility and distensibility of the esophagus in the patients with achalasia, including repetitive antegrade or retrograde contractions. EndoFLIP can detect achalasia patients with relatively low IRP, which was difficult to diagnose using the current high-resolution manometry. EndoFLIP also provides information on the contractile activity and distensibility of the esophageal body in patients with achalasia. The use of provocative tests, newly added in Chicago classification 4.0 version, and EndoFLIP can expand understanding of esophageal motility disorders.

Reflux symptoms and oesophageal acidification in treated achalasia patients are often not reflux related

OBJECTIVE

After treatment, achalasia patients often develop reflux symptoms. Aim of this case-control study was to investigate mechanisms underlying reflux symptoms in treated achalasia patients by analysing oesophageal function, acidification patterns and symptom perception.

DESIGN

Forty treated achalasia patients (mean age 52.9 years; 27 (68%) men) were included, 20 patients with reflux symptoms (RS+; Gastro-Oesophageal Reflux Disease Questionnaire (GORDQ) ≥8) and 20 without reflux symptoms (RS-: GORDQ <8). Patients underwent measurements of oesophagogastric junction distensibility, high-resolution manometry, timed barium oesophagogram, 24 hours pH-impedance monitoring off acid-suppression and oesophageal perception for acid perfusion and distension. Presence of oesophagitis was assessed endoscopically.

RESULTS

Total acid exposure time during 24 hours pH-impedance was not significantly different between patients with (RS+) and without (RS-) reflux symptoms. In RS+ patients, acid fermentation was higher than in RS- patients (RS+: mean 6.6% (95% CI 2.96% to 10.2%) vs RS-: 1.8% (95% CI -0.45% to 4.1%, p=0.03) as well as acid reflux with delayed clearance (RS+: 6% (95% CI 0.94% to 11%) vs RS-: 3.4% (95% CI -0.34% to 7.18%), p=0.051). Reflux symptoms were not related to acid in both groups, reflected by a low Symptom Index. RS+ patients were highly hypersensitive to acid, with a much shorter time to heartburn perception (RS+: 4 (2-6) vs RS-:30 (14-30) min, p<0.001) and a much higher symptom intensity (RS+: 7 (4.8-9) vs RS-: 0.5 (0-4.5) Visual Analogue Scale, p<0.001) during acid perfusion. They also had a lower threshold for mechanical stimulation.

CONCLUSION

Reflux symptoms in treated achalasia are rarely caused by gastro-oesophageal reflux and most instances of oesophageal acidification are not reflux related. Instead, achalasia patients with post-treatment reflux symptoms demonstrate oesophageal hypersensitivity to chemical and mechanical stimuli, which may determine symptom generation.

Normative reference values for esophageal high-resolution manometry in healthy adults: A systematic review

Establishing normative values of high-resolution esophageal manometry is necessary for accurate interpretation and comparison of measurements. In this systematic review, we aimed to summarize normal values for different esophageal high-resolution manometry systems. Moreover, we assessed the effect of body position, bolus consistency, and provocative maneuvers on these normative thresholds. We searched Medline, Embase, and the Cochrane Library from January 1st, 2006, to January 20th, 2020, for studies that reported normative data of high-resolution manometry in healthy volunteers. We assessed methodological quality of the included studies and planned a descriptive analysis. We analyzed data from 54 articles describing normative thresholds in high-resolution manometry using solid-state or water-perfused systems. Forty-six studies performed the manometry study in the supine position with liquid swallows, whereas sixteen studies described normative values in the upright position. Twelve studies assessed normative values for different bolus consistencies, and nine studies evaluated different provocative maneuvers. There is a considerable variety of normative values for esophageal high-resolution manometry depending on the equipment used and the protocols performed to obtain measurements. This should be taken into account when evaluating measurements in clinical practice and when comparing results of published research studies.

Esophageal motility disorders on high-resolution manometry: Chicago classification version 4.0©

Chicago Classification v4.0 (CCv4.0) is the updated classification scheme for esophageal motility disorders using metrics from high-resolution manometry (HRM). Fifty-two diverse international experts separated into seven working subgroups utilized formal validated methodologies over two-years to develop CCv4.0. Key updates in CCv.4.0 consist of a more rigorous and expansive HRM protocol that incorporates supine and upright test positions as well as provocative testing, a refined definition of esophagogastric junction (EGJ) outflow obstruction (EGJOO), more stringent diagnostic criteria for ineffective esophageal motility and description of baseline EGJ metrics. Further, the CCv4.0 sought to define motility disorder diagnoses as conclusive and inconclusive based on associated symptoms, and findings on provocative testing as well as supportive testing with barium esophagram with tablet and/or functional lumen imaging probe. These changes attempt to minimize ambiguity in prior iterations of Chicago Classification and provide more standardized and rigorous criteria for patterns of disorders of peristalsis and obstruction at the EGJ.

Esophageal Baseline Impedance From High-resolution Impedance Manometry Correlates With Mean Nocturnal Baseline Impedance From pH-impedance Monitoring

Background/Aims

Esophageal baseline impedance (BI) can be extracted from pH-impedance tracings as mean nocturnal baseline impedance (MNBI), and from high-resolution impedance manometry (HRIM), but it is unknown if values are similar between acquisition methods across HRIM manufacturers. We aim to assess correlations between MNBI and BI from HRIM (BI-HRIM) from 2 HRIM manufacturers in the setting of physiologic acid exposure time (AET).

Methods

HRIM and pH-impedance monitoring demonstrating physiologic AET (< 4%) off proton pump inhibitors were required. BI-HRIM was extracted as the average from 5 cm and 10 cm above the lower esophageal sphincter. Distal BI-HRIM (DBI-HRIM) was also extracted from the most distal channel (Medtronic studies). MNBI was extracted from 6 channels. Concordance between BI-HRIM across manufacturers with MNBI was analyzed.

Results

Thirty-six patients met the inclusion criteria (59.6 ± 1.7 years; 22% female; body mass index 30.5 ± 0.7; AET 1.6 ± 0.2%). Although MNBI was similar at all channels (P ≥ 0.18), Diversatek BI-HRIM was lower than Medtronic BI-HRIM (P = 0.003). Overall, BI-HRIM correlated with MNBI at corresponding recording sites, 7 cm and 9 cm (P < 0.05), but not at other sites (P ≥ 0.19). Pearson’s correlations > 0.5 were seen at MNBI at 7 cm for both systems, and at 9 cm for Medtronic. DBI-HRIM correlated with MNBI at 3 cm and 5 cm (P < 0.03), but not at other locations (P > 0.1).

Conclusions

While numeric differences exist between manufacturers, BI-HRIM correlates with MNBI from corresponding channels in patients with physiologic AET. Comparison with AET elevation is needed to determine correlations between pathologic MNBI with BI-HRIM across manufacturers. The optimal HRIM channels from which BI values should be extracted also warrants further study.

Recommendations of the Russian Gastroenterological Association on Clinical Use of High-Resolution Manometry in Diagnosis of Esophageal Disorders

Aim. Current recommendations of the Russian Gastroenterological Association on clinical use of high-resolution manometry in diagnosis of esophageal disorders are intended to assist in clinical decision making, terminology standardisation and interpretation of clinical data.

Key points. In 2018, a joint meeting of the Russian Gastroenterological Association and Russian Neurogastroenterology and Motility Group approved unified terminology and classification of esophageal motor function disorders for high-resolution manometry diagnosis.

Gastrointestinal patient complaints typically concern esophageal disorders such as dysphagia, regurgitation, heart-burn, chest pain or belching. To exclude erosive and ulcerative lesions, eosinophilic esophagitis and organic changes, esophagogastroduodenoscopy and biopsy are recommended in pre-treatment. Upon excluding mucosal lesions and esophageal lumen obstruction as causal for symptoms, use of high-resolution manometry is recommended. This method of esophageal examination has become the “gold standard” in diagnosis of motor disorders.

High-resolution manometry enables detailed investigation of integral quantitative and qualitative characteristics of esophagus motor function and specific related disorders, analysis of esophageal contractile propagation and strictly coordinated synchronous peristalsis of upper esophageal sphincter, esophagus and lower esophageal sphincter, which malfunction may provoke development of achalasia, esophagospasm, hiatal hernia, ineffective eso pha geal motility and other motor disorders.

Conclusion. High-resolution manometry is a relatively new method for study of esophagus motor function gaining increasingly wide application in clinical practice. It enables a medical professional to obtain evidence that may critically affect the choice of optimal patient care strategy and effective treatment. Current recommendations are based on an extensive review of up-to-date information and will be updated with new corpus of clinical data and assessment emerging in evidential medicine to provide gastroenterologists country-wide with latest scientific and practical guidelines.

Effect of Body Position on High-resolution Esophageal Manometry Variables and Final Manometric Diagnosis

Background/Aims

According to the Chicago classification version 3.0, high-resolution manometry (HRM) should be performed in the supine position. However, with the patient in the upright/sitting position, the test could more closely simulate real-life behavior and may be better tolerated. We performed a systematic review of the literature to search whether the manometric variables and the final diagnosis are affected by positional changes.

Methods

A literature search was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement. Studies published in English that compared HRM results in different body positions were included. Moreover, the change in diagnosis of esophageal motility disorders according to the shift of body position was investigated.

Results

Seventeen studies including 1714 patients and healthy volunteers met the inclusion criteria. Six studies showed a significant increase in lower esophageal sphincter basal pressure in the supine position. Integrated relaxation pressure was significantly higher in the supine position in 10 of 13 studies. Distal contractile index was higher in the supine position in 9 out of 10 studies. One hundred and fifty-one patients (16.4%) out of 922 with normal HRM in the supine position were diagnosed with ineffective esophageal motility (IEM) when the test was performed in the upright position (P < 0.001).

Conclusions

Performing HRM in the upright position affects some variables and may change the final manometric diagnosis. Further studies to determine the normal values in the sitting position are needed.

NORMAL VALUES OF ESOPHAGEAL HIGH-RESOLUTION MANOMETRY: A BRAZILIAN MULTICENTER STUDY

ABSTRACT BACKGROUND: The high-resolution manometry has been a significant advance in esophageal diagnostics. There are different types of catheter and systems devices to capture esophageal pressures that generate variable data related to Chicago Classification (CC) and consequently influence normal values results. There are not normative data for the 24-channel water-perfused high-resolution manometry system most used in Brazil with healthy volunteers in supine posture. OBJECTIVE: To determine manometric esophageal normative values for a 24-channel water-perfused high-resolution manometry catheter in supine posture using healthy volunteers according to CC 3.0 parameters. METHODS: A total of 92 volunteers with no gastrointestinal symptoms or medications affecting GI motility underwent esophageal high-resolution manometry by standard protocol. Age, gender and manometry parameters analyzed using Alacer software were collected. The median, range, and 5th and 95th percentiles (where applicable) were obtained for all high-resolution manometry metrics. Normal value percentiles were defined as 95th integrated relaxation pressure, 5th-100th distal contractile integral, and 5th distal latency. RESULTS: The mean age was 40.5±13.2 years. Our normative metrics were integrated relaxation pressure <16 mmHg and distal contractile integral (708-4111 mmHg.cm.s) distal latency was <6 s and peristaltic break size (>4 cm). For EGJ-CI the range 5th-95th was 21.7-86.9 mmHg.cm.s. CONCLUSION: This is the first report of normative data for the 24-channel water-perfused system in supine posture. It revealed higher integrated relaxation pressure and distal latency duration which suggest the need to change CC 3.0 cutoffs for this system. It is observed that there is a tendency that DCI >7000 mmHg.cm.s may represent the lower limit of hypercontractility, and when <700 mmHg.cm.s (<5% percentile) interpreted as ineffective esophageal motility or failcontraction. Also compared to Chicago 3.0, higher integrated relaxation pressure and duration of distal latency were found. We emphasize that these data must be confirmed by future studies.

Durability of Esophageal Motor Disorders Identified on High-Resolution Esophageal Manometry: A Case Series

Background/Aim

Diagnosis of esophageal motor disorders using high-resolution esophageal manometry (HREM) may result in medical, endoscopic or surgical intervention. However, prior to any intervention, durability of the HREM findings should be established. The aim of this case series was to assess 25 patients who had undergone HREM twice, at least 6 months apart, and to determine the durability of the initial manometric diagnosis.

Methods and Patients

This is a case series of 25 patients who underwent HREM at least twice, 6 months apart, at a large safety net hospital. All patients were evaluated in between the tests for any clinical intervention. Demographics, patients’ indication for HREM and clinical presentation were documented as well.

Results

Of the 25 patients, HREM results improved in 32%, worsened in 20% and were unchanged in 48%. Some interventions were employed between the first and second HREM diagnosis. Those associated with an improved diagnosis included doubling the proton pump inhibitor (PPI) dose, re-starting a PPI, adding a histamine 2 blocker (H2 blocker) and use of empiric dilation.

Conclusions

In this case series, about half of the patients undergoing two esophageal manometries, at least 6 months apart, demonstrated lack of durability of their initially diagnosed esophageal motor disorder.

On the nature of high-amplitude propagating pressure waves in the human colon

Characterization of high-amplitude propagating pressure waves (HAPWs or HAPCs) plays a key role in diagnosis of colon dysmotility using any type of colonic manometry. With the introduction of high-resolution manometry, more insight is gained into this most prominent propulsive motor pattern. Here, we use a water-perfused catheter with 84 sensors with intervals between measuring points of 1 cm throughout the colon, for 6-8 h, in 19 healthy subjects. The catheter contained a balloon to evoke distention. We explored as stimuli a meal, balloon distention, oral prucalopride, and bisacodyl injection, with a goal to optimally evoke HAPWs. We developed a quantitative measure of HAPW activity, the "HAPW Index." Our protocol elicited 290 HAPWs. 21% of HAPWs were confined to the proximal colon with an average amplitude of 75.3 ± 3.3 mmHg and an average HAPW Index of 440 ± 58 mmHg·m·s. 29% of HAPWs started in the proximal colon and ended in the transverse or descending colon, with an average amplitude of 87.9 ± 3.1 mmHg and an average HAPW Index of 3,344 ± 356 mmHg·m·s. Forty-nine percent of HAPWs started and ended in the transverse or descending colon with an average amplitude of 109.3 ± 3.3 mmHg and an average HAPW Index of 2,071 ± 195 mmHg·m·s. HAPWs with and without simultaneous pressure waves (SPWs) initiated the colo-anal reflex, often abolishing 100% of anal sphincter pressure. Rectal bisacodyl and proximal balloon distention were the most optimal stimuli to evoke HAPWs. These measures now allow for a confident diagnosis of abnormal motility in patients with colonic motor dysfunction.NEW & NOTEWORTHY High-amplitude propagating pressure waves (HAPWs) were characterized using 84 sensors throughout the entire colon in healthy subjects, taking note of site of origin, site of termination, amplitude, and velocity, and to identify optimal stimuli to evoke HAPWs. Three categories of HAPWs were identified, including the associated colo-anal reflex. Proximal balloon distention and rectal bisacodyl were recognized as reliable stimuli for evoking HAPWs, and a HAPW Index was devised to quantify this essential colonic motor pattern.

Normal study or minor motor disorders detected on high-resolution oesophageal manometry - are they relevant?

Introduction

The clinical significance of normal motility or minor peristaltic disorders, noted on esophageal manometry, in symptomatic patients is unclear.

Aim

To determine the clinical presentation, response to treatment, and outcomes at 2-year follow-up in symptomatic patients with normal manometry and minor peristaltic disorders.

Material and methods

This prospective cohort study included patients between 18 and 80 years old. Patients with previous upper gastrointestinal surgery, prior dilation or myotomy, and major motility disorders or EGJ outflow obstruction as per CC v 3.0 were excluded. The cohort was divided into two groups: normal manometry (Gp1) and minor peristaltic defects (Gp2). Study subjects were contacted for follow-up at 6, 12, and 24 months from the date of initial high-resolution oesophageal manometry study. Details of drug use, symptom control, and requirement of anti-reflux procedures in both groups were obtained.

Results

Fifty-six patients (median age: 42.3 years, males 72%) formed the study cohort: Gp1 - 35 (62.5%) and Gp2 - 21 (37.5%). The patients in the two groups were comparable in terms of symptoms (p = 0.94) and treatment (p = 0.15) at presentation. On follow-up, the majority of the cases (76.8%) reported improvement in symptoms at 2 years. None required anti-reflux procedures. There were no significant differences in the symptom profile and drug use in patients in the two groups at various time periods.

Conclusions

Patients with normal and minor oesophageal motor function abnormalities do not worsen over time.

ALTERED ESOPHAGEAL MOTILITY DURING PERCEPTION OF BOLUS TRANSIT IN HEALTHY VOLUNTEERS

BACKGROUND

The perception of bolus transit through the thoracic esophagus may be caused by altered esophageal anatomy and function.

OBJECTIVE

To evaluate the hypothesis that, in healthy volunteers, swallows followed by perception of esophageal bolus transit are associated with changes in esophageal motility.

METHODS

Simultaneous evaluation of motility and perception of esophageal bolus transit was performed in 22 healthy volunteers. Esophageal motility was evaluated by high-resolution manometry with a 32-channel solid state catheter. Each volunteer performed, in the sitting position, 10 swallows of a 5 mL bolus of saline and 10 swallows of pieces of 1 cm3 of bread, with an interval of at least 30 seconds between swallows. After each swallow the volunteers were asked about the perception of bolus transit through the esophagus.

RESULTS

Perception of bolus transit occurred in 11.7% of liquid swallows and in 48.1% of solid swallows. In liquid swallows the perception was associated with higher distal contractile integral and shorter proximal contraction length. Perception of solid bolus transit was associated with a longer distal latency, longer proximal contraction length, lower proximal contractile integral and shorter proximal contraction duration.

CONCLUSION

The perception of swallowed bolus transit through the esophagus in healthy individuals is more frequent with solid than liquid swallows and is associated with changes in proximal esophageal contractions.

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.

How I Approach Dysphagia

PURPOSE OF REVIEW

This review presents an overview of the diagnostic approach to esophageal dysphagia and summarizes recent epidemiological trends and technical advancements.

RECENT FINDINGS

The evaluation of dysphagia begins with a detailed history followed by endoscopy to evaluate for any structural abnormalities including malignancy. This is especially true given the emergence of eosinophilic esophagitis (EoE) as a dominant cause of esophageal dysphagia. In fact, it is now standard practice to obtain esophageal biopsies during endoscopy performed to evaluate dysphagia, since EoE can present without the characteristic mucosal features of rings, furrows, and exudate. Achalasia is also more frequently encountered since the introduction of high-resolution manometry (HRM) and the Chicago Classification into clinical practice. The Chicago Classification provides a stepwise diagnostic algorithm for evaluating HRM studies and systematically diagnosing esophageal motility disorders. Lastly, the functional lumen imaging probe (FLIP) is a novel technology that has added insight into both achalasia and EoE. Measuring esophageal distensibility with FLIP has useful prognostic implications for both diseases, and FLIP can identify motility abnormalities in achalasics not detected with HRM. A careful history is key to the efficient evaluation of dysphagia, and endoscopy is usually the first diagnostic study to obtain. For patients with prominent reflux symptoms, an empiric trial with proton pump inhibitors is reasonable then because reflux disease is such a common cause of dysphagia. Thereafter, patients should undergo HRM to evaluate for a motility disorder, and FLIP can provide complementary data to guide management.

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 differences in the esophageal motility between liquid and solid bolus swallows: A multicenter high-resolution manometry study in Chinese asymptomatic volunteers

BACKGROUND

The results of the esophageal body motility differences between liquid and solid swallows from high-resolution manometry (HRM) studies are not consistent. The information of the frequency of ineffective liquid and solid bolus swallows in healthy individuals during HRM procedure is limited. The normative values of the HRM parameters of both liquid and solid swallows for Chinese population are lacking.

METHODS

The esophageal HRM data of 101 healthy volunteers from multicenters in China were analyzed. The values of the HRM parameters were summarized and compared between liquid and solid swallows. The frequencies of ineffective liquid and solid swallows were summarized.

RESULTS

Esophagus contracted stronger and slower in solid bolus swallows than water swallows with HREM. Ineffective water swallow (DCI < 450 mm Hg.s.cm) and ineffective bread swallow (DCI < 800 mm Hg.s.cm) were frequently seen in asymptomatic individuals. The adding of bread swallows to the HREM procedure might cause diagnostic change in about 15.8% (16/101) of the asymptomatic individuals.

CONCLUSIONS

The vigor and velocity of the esophageal peristalsis between liquid and solid bolus swallows are different. Ineffective water and solid bolus swallows are not rare. Adding solid bolus swallows brings diagnostic change, and it may be needed routinely for the HRM procedure.

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.

Utility of Esophageal High-Resolution Manometry in Clinical Practice: First, Do HRM

Esophageal high-resolution manometry (HRM) has advanced the understanding of esophageal motor function and the ability to diagnose and manage disorders of esophageal motility. In this review, we describe the indications for and the technical performance of HRM. The Chicago classification of esophageal motor function, now in its third iteration, streamlines and standardizes the nomenclature and basic interpretation of HRM data depicted as Clouse topographic plots. In clinical practice, HRM is an important diagnostic test for patients with dysphagia as well as patients with suspected gastroesophageal reflux disease (GERD), particularly in those patients with a suboptimal symptomatic response to antisecretory therapy. HRM can support diagnoses such as achalasia, as well as provide evidence for behavioral disorders such as rumination syndrome or supragastric belching with the assistance of postprandial HRM with impedance. Further, the GERD classification of motor function introduces a three-part hierarchical evaluation of esophageal motor function in GERD, highlighting the value of assessment of esophageal contractile reserve through provocative maneuvers during HRM such as multiple rapid swallows.

Improving High-resolution Impedance Manometry Using Novel Viscous and Super-viscous Substrates in the Supine and Upright Positions: A Pilot Study

Background/Aims

Swallows with viscous or solid boluses in different body positions alter esophageal manometry patterns. Limitations of previous studies include lack of standardized viscous substrates and the need for chewing prior to swallowing solid boluses. We hypothesize that high-resolution impedance manometry (HRiM) using standardized viscous and super-viscous swallows in supine and upright positions improves sensitivity for detecting esophageal motility abnormalities when compared with traditional saline swallows. To establish normative values for these novel substrates, we recruited healthy volunteers and performed HRiM.

Methods

Standardized viscous and super-viscous substrates were prepared using “Thick-It” food thickener and a rotational viscometer. All swallows were administered in 5-mL increments in both supine and upright positions. HRiM metrics and impedance (bolus transit) were calculated. We used a paired two-tailed t test to compare all metrics by position and substrate.

Results

The 5-g, 7-g, and 10-g substrates measured 5000, 36 200, and 64 700 mPa sec, respectively. In 18 volunteers, we observed that the integrated relaxation pressure was lower when upright than when supine for all substrates (P < 0.01). The 10-g substrate significantly increased integrated relaxation pressure when compared to saline in the supine position (P < 0.01). Substrates and positions also affected distal contractile integral, distal latency, and impedance values.

Conclusions

We examined HRiM values using novel standardized viscous and super-viscous substrates in healthy subjects for both supine and upright positions. We found that viscosity and position affected HRiM Chicago metrics and have potential to increase the sensitivity of esophageal manometry.

Evaluation of symptomatic esophagogastric junction outflow obstruction

BACKGROUND AND AIM

Esophagogastric junction outflow obstruction (EGJOO) may be due to anatomical abnormalities, but it is unclear how to evaluate them after high-resolution manometry. We aimed to determine (i) clinical and high-resolution manometry parameters differentiating anatomical EGJOO from functional EGJOO, (ii) investigations chosen and yield for anatomical EGJOO, and (iii) clinical outcomes of functional EGJOO.

METHODS

Medical records of consecutive patients with symptomatic EGJOO from February 2012 to December 2015 were reviewed. EGJOO was defined as anatomical if investigations identified a macroscopic or microscopic pathology accounting for EGJOO.

RESULTS

Forty of 292 (13.7%) had EGJOO, of which 6/40 (15%) had anatomical EGJOO (two PPI-responsive esophageal eosinophilia, two infiltrating cancers, and two external compressions). Anatomical EGJOO was more likely to present with dysphagia (100% vs 29.4%, P = 0.001) and less likely with regurgitation (0% vs 41.2%, P = 0.05). Anatomical EGJOO had higher frequencies of premature contraction (50% vs 5.9%, P = 0.003) and lower mean values of distal latency (5.6 +/- 1.3 vs 6.7 +/- 1.2, P = 0.004). Computed tomography scans revealed 50% (3/6) of etiologies of anatomical EGJOO. Approximately, 73.5% (25/34) of patients with functional EGJOO had spontaneous resolution of their symptoms. One underwent pneumatic dilatation with symptom resolution while remaining eight with persistent symptoms were attributed to gastroesophageal reflux disease.

CONCLUSION

Anatomical causes are present in 15% of EGJOO. Evaluation is warranted especially in patients presenting with dysphagia. Esophageal biopsies, barium swallows, computed tomography scans, and endoscopic ultrasound are complementary in EGJOO evaluation. In patients with non-obstructive symptoms and no anatomical etiologies, monitoring for spontaneous resolution is an option.

Changes in Swallowing Symptoms and Esophageal Motility After Thyroid Surgery: A Prospective Cohort Study

INTRODUCTION

Swallowing difficulties, the pathophysiology behind which is incompletely understood, have been reported in 47-83% of goiter patients referred for thyroidectomy. We aimed at examining the influence of thyroid surgery on swallowing symptoms and esophageal motility.

METHODS

Thirty-three patients with benign nodular goiter undergoing thyroid surgery were included. All completed high-resolution esophageal manometry examinations and the goiter symptom scale score, assessed by the thyroid-specific patient-reported outcome measure. The evaluations were performed before and 6 months after surgery.

RESULTS

Before surgery, the goiter symptom score was median 39 points (range 2-61), which improved to median five points (range 1-52) after surgery (p < 0.001). The motility parameters were within the limits of normal swallowing physiology, both before and after surgery. Only the upper esophageal sphincter (UES) pressure increased significantly from 70.6 ± 27.7 to 87.7 ± 43.2 mmHg after surgery (p = 0.04). Using regression analyses, there was no significant correlation between change in goiter symptoms and weight of the removed goiter, motility parameters, or motility disturbances. However, patients undergoing total thyroidectomy experienced a larger reduction in pressure in the area of the UES and former thyroid gland after surgery in comparison with patients undergoing less extensive surgery.

CONCLUSIONS

Goiter symptoms improved significantly after thyroidectomy, but without correlation to esophageal motility disturbances. This information is essential when interpreting dysphagia in patients with nodular goiter, and when balancing patients' expectations to surgical goiter therapy.

REGISTRATION NUMBER

NCT03100357 ( www.clinicaltrials.org ).

NORMATIVE VALUES FOR A NEW WATER-PERFUSED HIGH RESOLUTION MANOMETRY SYSTEM

BACKGROUND

Esophageal manometry is the most reliable method to evaluate esophageal motility. High resolution manometry (HRM) provides topographic contour colored plots (Clouse Plots) with simultaneous analysis from the pharynx to the stomach. Both solid state and water-perfused systems are available.

OBJECTIVE

This study aims to determinate the normative data for a new water-perfused HRM.

METHODS

HRM was made in 32 healthy volunteers after 8 hours fasting. HRM system used consisted of a 24-channel water-perfused catheter (Multiplex, Alacer Biomedica, São Paulo, Brazil). The reusable catheter is made of polyvinyl chloride (PVC) with 4.7 mm of diameter. Side holes connected to pressure transducers are spaced 2 cm for the analysis from the pharynx to the lower esophageal sphincter (LES). Holes are spaced 5 mm and 120° in a spiral disposition in the LES area. The sensors encompass 34 cm in total. Upper esophageal sphincter (UES) parameters studied were basal and relaxation pressures. Esophageal body parameters were distal contractile integral (DCI), distal latency (DL) and break. LES parameters studied were basal pressure, integrated residual pressure (IRP), total and abdominal length. Variables are expressed as mean ± standard deviation, median (interquartile range) and percentiles 5-95th.

RESULTS

All volunteers (17 males, aged 22-62 years) completed the study and tolerated the HRM procedure well. Percentiles 5-95th range were calculated: Upper Esophageal Sphincter (UES) basal pressure 16.7-184.37 (mmHg), DL: 6.2-9.1 (s), DCI: 82.72-3836.61 (mmHg.s.cm), break: <7.19 (cm), LES basal pressure: 4.89-37.16 (mmHg), IRP: 0.55-15.45 (mmHg).

CONCLUSION

The performance and normative values obtained for this low-cost water-perfused HRM seems to be adequate for clinical use.

Normative values and factors affecting water-perfused esophageal high-resolution impedance manometry for a Chinese population

BACKGROUND

Combined esophageal high-resolution impedance manometry (HRIM) measures multiple pressures and bolus transit simultaneously, facilitating detailed assessment of esophageal motility. Currently, normative values for water-perfused HRIM systems for Chinese populations are lacking.

METHODS

Healthy volunteers were enrolled for comprehensive anthropometric measures, blood biochemistry tests, and an HRIM study using 22 water-perfused pressure sensors and 12 impedance channels. Ten 5-mL liquid swallows of saline at 30-second intervals were conducted. The following parameters were calculated: distal contractile integral (DCI), distal latency (DL), lower esophageal sphincter (LES) basal pressure, 4-second integrated relaxation pressure (IRP-4s), and complete bolus transit percentage. Normal values were established based on the 5th and 95th percentiles.

KEY RESULTS

All 66 participants (34 male, 32 female, aged 21-64 years) completed the study and tolerated the HRIM procedure well. The upper normal limit (95th percentile) of IRP-4 second was 20 mmHg. The 5th-95th percentile range for DCI, DL, and complete bolus transit was 99-2186 mmHg●s●cm, 6.2-11.3 second, and 50%-100%, respectively. Age was negatively correlated with DL. Females had significantly higher upper limits for IRP-4s and median DCI than males. Multivariate analyses confirmed that IRP-4s was higher in females, and that higher body mass index and waist circumference were associated with reduced DL and better bolus transit, respectively.

CONCLUSIONS AND INFERENCES

We established normative values for the water-perfused HRIM system for a Chinese population. Gender and anthropometric factors may affect various major HRIM parameters and should be taken into account when interpreting HRIM results in clinical practice.

Gastric accommodation in healthy subjects studied by ultrasound, manometry, and impedancemetry

BACKGROUND

Gastric accommodation to a meal may be important in the pathogenesis of upper gastrointestinal disorders, but has been difficult to investigate in a minimally invasive fashion.

METHODS

We studied gastric and lower esophageal physiology during food intake, combining transabdominal ultrasound, multichannel high-resolution impedance-manometry (HRIM) and a symptom questionnaire. A HRIM catheter was distally positioned at incisura angularis and 300 mL saline with 75 g glucose was ingested. Target variables were recorded for 30 min after fluid intake.

KEY RESULTS

Fifteen healthy subjects' participated (11W/4M, median age 23.8 y) and all accepted the meal with few symptoms. At incisura angularis maximum change in pressure from pre-intake values was -7.4 mmHg after 60 s (P < .0001), rising to pre-intake values within 20 min. The corresponding area increased significantly from pre-intake values of 8.0 cm² to 14.1 cm² shortly after intake (P = .0012), peaked at 5 min and slowly decreased towards 30 min. The corresponding maximum change in stress from pre-intake pressure values was -59.2 mmHg shortly after (P < .0001), reaching pre-intake values within 20 min. Strain rose from 0 shortly before to 0.36 shortly after (P < .0001), peaking at 5 min. At incisura angularis, fullness was positively correlated with area and to strain, while fullness, area, and stress were negatively correlated with pressure.

CONCLUSIONS & INFERENCES

The multimodal method enabled assessment of the gastric accommodation reflex, stress and strain in the stomach. It triggered few symptoms in healthy volunteers. We propose it to be a more physiological replacement of the barostat technique.

Clinicomanometric factors associated with clinically relevant esophagogastric junction outflow obstruction from the Sandhill high-resolution manometry system

BACKGROUND

Integrated relaxation pressure (IRP) is a key metric for diagnosing esophagogastric junction outflow obstruction (EGJOO). However, its normal value might be different according to the manufacturer of high-resolution manometry (HRM). This study aimed to investigate optimal value of IRP for diagnosing EGJOO in Sandhill HRM and to find clinicomanometric variables to segregate clinically relevant EGJOO.

METHODS

We analyzed 262 consecutive subjects who underwent HRM between June 2011 and December 2016 showing elevated median IRP (> 15 mm Hg) but did not satisfy criteria for achalasia. Clinically relevant subjects were defined as follows: (i) subsequent HRM met achalasia criteria during follow-up (early achalasia); (ii) Eckardt score was decreased at least two points without exceeding a score of 3 after pneumatic dilatation (variant achalasia); and (iii) significant passage disturbance on esophagogram without structural abnormality (possible achalasia).

KEY RESULTS

Seven subjects were clinically relevant, including two subjects with early achalasia, four subjects with variant achalasia, and one subject with possible achalasia. All clinically relevant subjects had IRP 20 mm Hg or above. Among subjects (n = 122) with IRP 20 mm Hg or more, clinically relevant group (n = 7) had significantly higher rate of dysphagia (100% vs 24.3%, P < .001) and compartmentalized pressurization (85.7% vs 21.7%, P = .001) compared to clinically non-relevant group (n = 115).

CONCLUSIONS & INFERENCES

Our results suggest that IRP of 20 mm Hg or higher could segregate clinically relevant subjects showing EGJOO in Sandhill HRM. Additionally, if subjects have both dysphagia and compartmentalized pressurization, careful follow-up is essential.

Normal Values of High-Resolution Manometry in Supine and Upright Positions in a Thai Population

BACKGROUND

Although cut-off values used in high-resolution manometry (HRM) to diagnose esophageal motility disorders are based on representative samples of the US population and assume a supine position, differences in population and body positioning can reportedly affect results.

AIMS

To establish normal HRM values for Thai people in both supine and upright positions.

METHODS

Forty-one healthy subjects were recruited, each of whom underwent solid-state HRM with ten 5-mL swallows of water in both the supine and upright positions. Measuring parameters according to the Chicago classification criteria (CC v3.0) were included, for which the mean, median and 5th and 95th percentiles (PCTLs) were calculated.

RESULTS

The results corresponded with the CC v3.0 criteria, except for the mean, and 5th PCTL of the distal contractile integral (DCI), which were lower for this population. In the upright position, the mean and median values for DCI, intrabolus pressure and integrated relaxation pressure were significantly decreased, whereas the length of the transitional zone was significantly increased. The limitations of this study include: (1) the relatively low number of participants, (2) the limited recruitment of participants only at Ramathibodi Hospital and (3) the limited recruitment of only young and middle-aged participants.

CONCLUSIONS

We established normal values for the HRM parameters in a representative sample of the Thai population. Our supine results still prove that the use of the CC v3.0 is preferable. HRM testing in patients measured in the upright position should be analyzed based on the normative values obtained from upright swallow studies.

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.

High-resolution Impedance Manometry after Sleeve Gastrectomy: Increased Intragastric Pressure and Reflux are Frequent Events

INTRODUCTION AND PURPOSE

Sleeve gastrectomy (SG) is gaining ground in the field of bariatric surgery. Data are scarce on its impact on esophagogastric physiology. Our aim was to evaluate the impact of SG on esophagogastric motility with high-resolution impedance manometry (HRIM) and to assess the usefulness of HRIM in patients with upper gastrointestinal (GI) symptoms after SG.

METHODS

A retrospective analysis of 53 cases of HRIM performed after SG was conducted. Upper GI symptoms at the time of HRIM were scored. HRIM was analyzed according to the Chicago classification v3.0. A special attention was devoted to the occurrence of increased intragastric pressure (IIGP) after water swallows and reflux episodes as detected with impedance. A measurement of sleeve volume and diameter was performed with CT scan in a subgroup of patients.

RESULTS

IIGP occurred very frequently in patients after SG (77 %) and was not associated with any upper GI symptoms, specific esophageal manometric profile, or impedance reflux. Impedance reflux episodes were also frequently observed after SG (52 %): they were significantly associated with gastroesophageal reflux (GER) symptoms and ineffective esophageal motility. The sleeve volume and diameters were also significantly smaller in patients with impedance reflux episodes (p < 0.01).

CONCLUSION

SG significantly modified esophagogastric motility. IIGP is frequent, not correlated to symptoms, and should be regarded as a HRIM marker of SG. Impedance reflux episodes were also frequent, associated with GER symptoms and esophageal dysmotility. HRIM may thus have a clinical impact on the management of patients with upper GI symptoms after SG.