High-Resolution Manometry Thresholds and Motor Patterns Among Asymptomatic Individuals

Ineffective esophageal motility: Characterization and outcomes across pediatric neurogastroenterology and motility centers in the United States

OBJECTIVES

Ineffective esophageal motility (IEM) on high-resolution manometry (HRM) is not consistently associated with specific clinical syndromes or outcomes. We evaluated the prevalence, clinical features, management, and outcomes of pediatric IEM patients across the United States.

METHODS

Clinical and manometric characteristics of children undergoing esophageal HRM during 2021-2022 were collected from 12 pediatric motility centers. Clinical presentation, test results, management strategies, and outcomes were compared between children with IEM and normal HRM.

RESULTS

Of 236 children (median age 15 years, 63.6% female, 79.2% Caucasian), 62 (23.6%) patients had IEM, and 174 (73.7%) patients had normal HRM, with similar demographics, medical history, clinical presentation, and median symptom duration. Reflux monitoring was performed more often for IEM patients (25.8% vs. 8.6%, p = 0.002), but other adjunctive testing was similar. Among 101 patients with follow-up, symptomatic cohorts declined in both groups in relation to the initial presentation (p > 0.107 for each comparison) with management targeting symptoms, particularly acid suppression. Though prokinetics were used more often and behavioral therapy less often in IEM (p ≤ 0.015 for each comparison), symptom outcomes were similar between IEM and normal HRM. Despite a higher proportion with residual dysphagia on follow-up in IEM (64.0% vs. 39.1%, p = 0.043), an alternate mechanism for dysphagia was identified more often in IEM (68.8%) compared to normal HRM (27.8%, p = 0.017).

CONCLUSIONS

IEM is a descriptive manometric pattern rather than a clinical diagnosis requiring specific intervention in children. Management based on clinical presentation provides consistent symptom outcomes.

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.

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.

A practical approach to ineffective esophageal motility

BACKGROUND AND PURPOSE

Ineffective esophageal motility (IEM) is the most frequently diagnosed esophageal motility abnormality and characterized by diminished esophageal peristaltic vigor and frequent weak, absent, and/or fragmented peristalsis on high-resolution esophageal manometry. Despite its commonplace occurrence, this condition can often provoke uncertainty for both patients and clinicians. Although the diagnostic criteria used to define this condition has generally become more stringent over time, it is unclear whether the updated criteria result in a more precise clinical diagnosis. While IEM is often implicated with symptoms of dysphagia and gastroesophageal reflux disease, the strength of these associations remains unclear. In this review, we share a practical approach to IEM highlighting its definition and evolution over time, commonly associated clinical symptoms, and important management and treatment considerations. We also share the significance of this condition in patients undergoing evaluation for anti-reflux surgery and consideration for lung transplantation.

Identification of Achalasia Within Absent Contractility Phenotypes on High-Resolution Manometry: Prevalence, Predictive Factors, and Treatment Outcome

INTRODUCTION

Absent contractility on high-resolution manometry (HRM) defines severe hypomotility but needs distinction from achalasia. We retrospectively identified achalasia within absent contractility using HRM provocative maneuvers, barium esophagography, and functional lumen imaging probe (FLIP).

METHODS

Adult patients with absent contractility on HRM during the 4-year study period were eligible for inclusion. Inadequate studies, achalasia after therapy, or prior foregut surgery were exclusions. Upright integrated relaxation pressure (IRP) >12 mm Hg, panesophageal pressurization, and/or elevated IRP on multiple rapid swallows and rapid drink challenge (RDC) were considered abnormal. Esophageal barium retention and abnormal esophagogastric junction distensibility index (<2.0 mm 2 /mm Hg) on FLIP defined achalasia. Clinical, endoscopic, and motor characteristics of patients with achalasia were compared with absent contractility without obstruction.

RESULTS

Of 164 patients, 20 (12.2%) had achalasia (17.9% of 112 patients with adjunctive testing), while 92 did not, and 52 did not undergo adjunctive tests. Achalasia was diagnosed regardless of IRP value, but the median supine IRP was higher (odds ratio 1.196, 95% confidence interval 1.041-1.375, P = 0.012). Patients with achalasia were more likely to present with dysphagia (80.0% vs 35.9%, P < 0.001), with obstructive features on HRM maneuvers (83.3% vs 48.9%, P = 0.039), but lower likelihood of GERD evidence (20.0% vs 47.3%, P = 0.027) or large hiatus hernia (15.0% vs 43.8%, P = 0.002). On multivariable analysis, dysphagia presentation ( P = 0.006) and pressurization on RDC ( P = 0.027) predicted achalasia, while reflux and presurgical evaluations and lack of RDC obstruction predicted absent contractility without obstruction.

DISCUSSION

Despite HRM diagnosis of absent contractility, achalasia is identified in more than 1 in 10 patients regardless of IRP value.

De Novo Gastroesophageal Reflux Disease Symptoms Are Infrequent after Sleeve Gastrectomy at 2-Year Follow-Up Using a Comprehensive Preoperative Esophageal Assessment

Pathological obesity is a growing public health concern, and its association with gastroesophageal reflux disease (GERD) poses challenges in selecting the appropriate bariatric procedure. Sleeve gastrectomy (SG) has become a popular choice due to its simplicity and effectiveness in weight loss. However, concerns regarding postoperative GERD have been raised. This study aimed to evaluate the association between preoperative assessment of esophageal function and the risk of developing postoperative GERD in patients undergoing SG. A comprehensive evaluation was conducted, including symptom assessment, upper endoscopy, high-resolution esophageal manometry (HRM), and 24 h esophageal pH impedance monitoring (MII-pH). A total of 500 obese patients were included, and their data were compared with 25 healthy volunteers. This study revealed that patients without GERD symptoms, normal endoscopy, HRM, and MII-pH were suitable candidates for SG, with low risk of developing postoperative GERD. The addition of fundoplication techniques to SG may be considered in patients with mild reflux or those at risk of developing it. This study emphasizes the importance of preoperative evaluation in selecting the appropriate bariatric procedure to minimize the risk of postoperative GERD and expand the indications for SG in obese patients.

Association between esophageal motor disorders and pulmonary involvement in patients affected by systemic sclerosis: a retrospective study

Systemic sclerosis (SSc) is a rare autoimmune disease of the connective tissue that can affect multiple organs. The esophagus is the most affected gastrointestinal tract, while interstitial lung disease (ILD) is a main feature associated with SSc. The aim of the present study was to evaluate the association and prognostic implication between motor esophageal disorders and pulmonary involvement in SSc patients. We retrospectively assessed patients with SSc who underwent both the HRM with the new Chicago Classification 4.0 and pulmonary evaluation comprehensive of function tests and high-resolution computer tomography (HrCT) with the use of Warrick score. A total score ≥ 7 was considered predictive of ILD, while a score ≥ 10 in a HrCT acquired prospectively from baseline evaluation was considered to establish significant interstitial involvement. Forty-two patients were included. We found a score ≥ 7 in 11 patients with aperistalsis, in 6 subjects with IEM and in 6 patients with a normal manometry. Otherwise, a score < 7 was observed in 3 patients with aperistalsis, and in 2 and 14 patients with IEM and with a normal contractility, respectively. Higher scores were observed in subjects with absent contractility or ineffective esophageal motility than subjects with normal motility, indeed DCI and HrCT score were inversely correlated in linear and logarithmic regression analysis. Prospectively, lower baseline LESP and greater HrCT scores at follow-up evaluation were significantly correlated. This study shows an association between motor esophageal disorder and pulmonary involvement in SSc patients: more severe is the esophageal involvement, more critical is the pulmonary disease.

Major mixed motility disorders: An important subset of esophagogastric junction outflow obstruction

BACKGROUND

Esophagogastric junction outflow obstruction (EGJOO) is an esophageal motility disorder characterized by a lack of relaxation of the esophagogastric junction (EGJ), with preserved esophageal body peristalsis. We propose new terminology for the coexistence of EGJOO with hypercontractile esophagus and distal esophageal spasm as a major mixed motility disorder (MMMD), and normal peristalsis or a minor disorder of peristalsis such as ineffective esophageal motility with EGJOO as isolated or ineffective EGJOO (IEGJOO).

METHODS

We reviewed prior diagnoses of EGJOO, stratified diagnoses as IEGJOO or MMMD, and compared their symptomatic presentations, high-resolution manometry (HRM) and endoluminal functional lumen imaging probe (EndoFLIP) metrics, and treatment responses at 2-6 months of follow-up.

RESULTS

Out of a total of 821 patients, 142 met CCv3 criteria for EGJOO. Twenty-two were confirmed by CCv4 and EndoFLIP as having EGJOO and were clinically managed. Thirteen had MMMD, and nine had IEGJOO. Groups had no difference in demographic data or presenting symptoms by Eckardt score (ES). HRM showed MMMD had greater distal contractile integral, frequency of hypercontractile swallows, and frequency of spastic swallows, and greater DI by EndoFLIP. Patients with MMMD showed greater reduction in symptoms after LES-directed intervention when measured by ES compared with IEGJOO (7.2 vs. 4.0).

CONCLUSION

Patients with MMMD and IEGJOO present similarly. Detectable differences in HRM portend different responses to endoscopic therapy. Because patients with MMMD have greater short-term prognosis, they should be considered a different diagnostic classification to guide therapy.

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.

The influence of supragastric belching severity on esophageal acid exposure and motility

BACKGROUND

Supragastric belching (SGB) is a phenomenon where air is rapidly sucked from the pharynx into the esophagus and immediately expelled through abdominal straining. It is considered a behavior disorder and is increasingly recognized not only in patients with excessive belching, but also in those with reflux-like symptoms. Increased prevalence of esophageal hypomotility and increased acid exposure were previously reported in small cohorts of SGB patients. We aimed to clarify the impact of SGB on motility, reflux, and acid exposure in a large cohort of SGB patients.

METHODS

In a single-center database study, we searched for patients with pathological SGB. MII-pH and Manometry tracings were manually re-evaluated in all patients. Demographic, clinical, motility, reflux, and SGB-related data were gathered.

KEY RESULTS

Three hundred and forty-eight patients were included. Heartburn, belching, and regurgitation were the most common symptoms. Ineffective esophageal motility (IEM) was found in 27% of patients. SGB related to 47% of all reflux and to 53.6% of acid reflux events, and accounted for 27.3% of acid exposure time (AET). In those with severe SGB, 62% of acid reflux events and 46% of AET were SGB-related.

CONCLUSIONS & INFERENCES

Supragastric belching is common, associated with higher incidence of IEM and is responsible for almost a third of esophageal acid burden. The impact of SGB is proportional to its severity. Diagnosis of SGB should be sought in patients with excessive belching and in patients with refractory reflux symptoms. Recognizing SGB and treating patients with behavioral therapy may alleviate acid exposure and improve quality of life.

Clinical Characteristics of Patients With Ineffective Esophageal Motility by Chicago Classification Version 4.0 Compared to Chicago Classification Version 3.0

Background/Aims

Chicago classification version 4.0 (CCv4.0) of esophageal motility disorders developed a more stringent diagnostic criteria for ineffective esophageal motility (IEM) than version 3.0. We studied the implications of the new diagnostic criteria on the prevalence of IEM, and clinically characterized and compared the population of patients who no longer meet diagnostic criteria for IEM to those who retain the diagnosis.

Methods

We included all consecutively performed high-resolution esophageal impedance manometries from 2014 to 2021. Three cohorts of patients with IEM were created: Patients with IEM by Chicago classification version 3.0 (CCv3.0; CC3 group), by CCv4.0 only (CC4 group), and by CCv3.0 who are now considered normal (Normal group). Demographics, manometric and reflux parameters, and clinical outcomes were compared.

Results

A total of 594 manometries were analyzed. Of those, 66 (11.1%) met criteria for IEM by CCv3.0 (CC3), 41 (62.0%) retained an IEM diagnosis using CCv4.0 criteria (CC4), while 25 (38.0%) patients no longer met criteria for IEM (Normal). The CC4 group had higher esophageal acid exposure, especially supine (% time - 18.9% vs 2.2%; P = 0.005), less adequate peristaltic reserve (22.0% vs 88.0%; P = 0.003), and higher Demeester score (49.0 vs 21.2; P = 0.017) compared to the Normal group. There was no difference in bolus clearance between the groups.

Conclusions

IEM under CCv4.0 has a stronger association with pathologic reflux, especially supine reflux, and inadequate peristaltic reserve, but impairment in bolus clearance is unchanged when compared with IEM diagnosed based on CCv3.0. Further studies are required to determine the implications of these findings on management strategies.

High-resolution manometry with additional maneuvers using the Starlet system: normative thresholds and diagnostic yields for relevant esophagogastric junction outflow disorders

BACKGROUND

Chicago classification version 4.0 suggests additional maneuvers, such as upright testing, multiple rapid swallows (MRS), and the rapid drink challenge (RDC), for high-resolution manometry (HRM) to minimize ambiguity in the diagnosis of esophageal motility disorders. The present study investigated normative thresholds for these new metrics using the Starlet system as well as their diagnostic yields for relevant esophagogastric outflow disorders (EGJOD).

METHODS

In study 1, 30 asymptomatic volunteers prospectively performed HRM including MRS and RDC in the supine/upright positions. We calculated normative thresholds for the new metrics, such as upright integrated relaxation pressure (IRP), upright intrabolus pressure (IBP), and IRP during RDC (RDC-IRP). In study 2, we retrospectively analyzed the HRM tracings of 82 patients who underwent HRM in both positions at our hospital to assess the diagnostic yields of HRM metrics.

RESULTS

Based on the results of study 1, we adopted the following normative thresholds: upright IRP < 20 mmHg, upright IBP < 21 mmHg, and RDC-IRP < 16 mmHg. In study 2, 45 patients with dysphagia or chest pain were included in the analysis to identify predictive factors for clinically relevant esophagogastric outflow disorders (true EGJOD). Supine/upright IRP, RDC-IRP, and pan-esophageal pressurization > 20 mmHg during RDC (RDC-PEP) predicted true EGJOD with RDC-PEP with the highest sensitivity of 91.7%.

CONCLUSIONS

HRM with additional maneuvers may facilitate the diagnosis of clinically relevant EGJOD.

Dysphagia Worsens With Increasing Ineffective Swallows Among Patients With Ineffective Esophageal Motility

INTRODUCTION

Ineffective esophageal motility (IEM) is the most common motility disorder identified on esophageal high-resolution manometry (HRM), but patients with this finding may be asymptomatic. Therefore, we aimed to identify specific HRM findings predictive of symptoms in IEM.

METHODS

Adult patients (≥18 y) who underwent HRM between March 2016 and July 2019 were retrospectively evaluated and reclassified according to Chicago Classification 4.0 (CC4.0). Demographic information, HRM parameters, and gastroesophageal reflux disease Health-Related Quality of Life Questionnaire responses were captured among those with normal manometry or IEM. We evaluated the association between heartburn, regurgitation, and dysphagia, with respect to HRM findings including ineffective swallows.

RESULTS

Of 379 patients, 243 (64.1%) had a normal manometry, 136 (35.9%) were on IEM spectrum, and 73 (19.3%) had conclusive IEM by CC4.0. Mean dysphagia scores were significantly higher in those with conclusive IEM compared with those with normal HRM (2.00 vs. 1.36, P=0.002), as was the percentage of individuals reporting dysphagia affecting daily activities (21.9% vs. 11.4%, P=0.02). Heartburn and regurgitation symptoms did not differ between groups. In a multivariable model of IEM patients, the percentage of ineffective swallows independently predicted a higher dysphagia burden (β regression coefficient: 0.032, P=0.04).

CONCLUSIONS

Applying the CC4.0 definition for conclusive IEM identifies a group of patients with worse dysphagia symptoms. Within this group, the percentage of ineffective swallows was an independent predictor of dysphagia severity. These findings may help practitioners and patients contextualize the heterogeneous diagnosis of IEM.

How provocative tests in addition to wet swallows during high-resolution manometry can direct clinical management

PURPOSE OF REVIEW

Provocative tests have been advocated to address limitations of high-resolution manometry (HRM) with wet swallows. We describe the commonly used provocative manometric manoeuvres [rapid drink challenge (RDC), multiple rapid swallows (MRS), solid swallows and the solid test meal (STM)], compare their diagnostic yield and accuracy to wet swallows, and outline their role in directing clinical management.

RECENT FINDINGS

Provocative testing with RDC and STM identifies a proportion of achalasia cases missed by standard testing, and RDC can play a similar role to radiology in the evaluation of treatment response. In EGJOO, provocative testing with RDC and STM not only increase the diagnostic yield, but can also help differentiate between spurious cases and those representing true outflow obstruction likely to respond to achalasia-type therapies. MRS and STM can help determine the clinical relevance (or otherwise) of ineffective oesophageal motility, and in this setting, MRS may predict the likelihood of postfundoplication dysphagia. RDC and STM can help identify cases of postfundoplication dysphagia more likely to respond to dilatation.

SUMMARY

Provocative testing has been shown to increase diagnostic yield of HRM, clarify inconclusive diagnoses, allows corroboration of dysmotility with patient symptoms and helps direct clinical management.

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.

[Chicago Classification ver. 4.0: Diagnosis of Peristaltic Disorder]

The Chicago Classification is being revised continuously for the accurate diagnosis of esophageal peristaltic disorders in which the etiology is unclear, and the disease behavior is heterogeneous. The ver. 4.0 was recently updated. A representative change in the diagnosis of esophageal peristaltic disorders of the ver. 4.0 showed that the distinction between major and minor disorders was eliminated and was divided into the following four diagnoses: absent contractility, distal esophageal spasm (DES), hypercontractile esophagus (HE), and ineffective esophageal motility. Compared to the ver. 3.0, it recommended a more detailed protocol of high-resolution esophageal manometry and methods of interpreting manometric. In addition, it emphasized the clinically relevant symptoms in diagnosing DES and HE, and presented provocative tests (e.g., multiple rapid swallow and rapid drinking challenge), as well as additional testing, including impedance, timed barium esophagogram and functional lumen imaging probe, which may provide more standardized and rigorous criteria for peristaltic patterns and to minimize the ambiguity in diagnosis. Although it will take time and effort to apply this revised Chicago Classification in clinical practice, it may help diagnose and manage patients with esophageal peristalsis disorder in the future.

Breaks in peristaltic integrity predict abnormal esophageal bolus clearance better than contraction vigor or residual pressure at the esophagogastric junction

BACKGROUND

High-resolution impedance manometry (HRIM) evaluates esophageal peristalsis and bolus transit. We used esophageal impedance integral (EII), the ratio between bolus presence before and after an expected peristaltic wave, to evaluate predictors of bolus transit.

METHODS

From HRIM studies performed on 61 healthy volunteers (median age 27 years, 48%F), standard metrics were extracted from each of 10 supine water swallows: distal contractile integral (DCI, mmHg cm s), integrated relaxation pressure (IRP, mmHg), and breaks in peristaltic integrity (cm, using 20 mmHg isobaric contour). Pressure and impedance coordinates for each swallow were exported into a dedicated, python-based program for EII calculation (EII ratio ≥ 0.3 = abnormal bolus clearance). Univariate and multivariate analyses were performed to assess predictors of abnormal bolus clearance.

KEY RESULTS

Of 591 swallows, 80.9% were intact, 10.5% were weak, and 8.6% failed. Visual analysis overestimated abnormal bolus clearance compared to EII ratio (p ≤ 0.01). Bolus clearance was complete (median EII ratio 0.0, IQR 0-0.12) in 82.0% of intact swallows in contrast to 53.3% of weak swallows (EII ratio 0.29, IQR 0.0-0.57), and 19.6% of failed swallows (EII ratio 0.5, IQR 0.34-0.73, p < 0.001). EII correlated best with break length (ρ = 0.52, p < 0.001), compared to IRP (ρ: -0.17) or DCI (ρ: -0.42). On ROC analysis, breaks predicted abnormal bolus transit better than DCI or IRP (AUC 0.79 vs. 0.25 vs. 0.44, p ≤ 0.03 for each). On logistic regression, breaks remained independently predictive of abnormal bolus transit (p < 0.001).

CONCLUSIONS & INFERENCES

Breaks in peristaltic integrity predict abnormal bolus clearance better than DCI or IRP in healthy asymptomatic subjects.

Dysphagia: Novel and Emerging Diagnostic Modalities

Among recent advances in diagnostics for dysphagia and esophageal motility disorders is the update to the Chicago Classification (version 4.0) for interpretation of high-resolution manometry (HRM) and diagnosis of esophageal motility disorders. The update incorporates application of complementary testing strategies during HRM, such as provocative HRM maneuvers, and recommendation for barium esophagram or functional luminal imaging probe (FLIP) panometry to help clarify inconclusive HRM findings. FLIP panometry also represents an emerging technology for evaluation of esophageal distensibility and motility at the time of endoscopy.

Making Sense of Nonachalasia Esophageal Motor Disorders

Achalasia is the prototypical obstructive motor disorder diagnosed using HRM, but non-achalasia motor disorders are often identified in symptomatic patients. The clinical relevance of these disorders are assessed using ancillary HRM maneuvers (multiple rapid swallows, rapid drink challenge, solid swallows) that augment the standard supine HRM evaluation by challenging peristaltic function. Finding obstructive motor physiology in non-achalasia motor disorders may raise the option of invasive management akin to achalasia. Certain non-achalasia disorders, particularly hypermotility disorders, may manifest as epiphenomena seen with esophageal hypersensitivity. Symptomatic management is offered for superimposed reflux disease, psychological disorders, functional esophageal disorders, and behavioral disorders.

Changes in the Treatment of Primary Esophageal Motility Disorders Imposed by the New Classification for Esophageal Motility Disorders on High Resolution Manometry (Chicago Classification 4.0)

The Chicago Classification is the most used classification for primary esophageal motility disorders (PEMD). This classification was recently updated to the 4.0 version. This opinion piece focuses on the possible implications for the treatment of PMED determined by the new classification. Chicago Classification 4.0 included two new concepts for the diagnosis of achalasia: (1) type III achalasia diagnosis demands 100% absent peristalsis defined as either failed peristalsis or spasm; (2) “inconclusive diagnosis of achalasia” was added as a possibility. Both may decrease unnecessary treatment. Esophagogastric junction outflow obstruction, distal esophageal spasm, and hypercontractile esophagus were only considered clinically significant when correlated to supportive testing and relevant clinical symptoms and in the absence of gastroesophageal reflux disease. This may decrease the surge of treatment, especially peroral endoscopic myotomy, based solely on manometric diagnosis.

[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.

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.

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.