Ineffective esophageal motility and the vagus: current challenges and future prospects

Esophageal Motility Abnormalities in Lung Transplant Recipients With Esophageal Acid Reflux Are Different From Matched Controls

Background/Aims

There is an increased incidence of gastroesophageal reflux disease (GERD) after lung transplantation (LT) that can be associated with graft dysfunction. It is unclear if the underlying esophageal motility changes in GERD are different following LT. This study aimed to use esophageal high-resolution manometry (HRM) to explore GERD mechanisms in LT recipients compared to matched controls.

Methods

This was a retrospective study including patients with pathologic acid reflux who underwent HRM and pH testing at our healthcare facility July 2012 to October 2019. The study included 12 LT recipients and 36 controls. Controls were matched in a 1:3 ratio for age, gender, and acid exposure time (AET).

Results

LT recipients had less hypotensive esophagogastric junction (EGJ) (mean EGJ-contractile integral 89.2 mmHg/cm in LT vs 33.9 mmHg/cm in controls, P < 0.001). AET correlated with distal contractile integral and total EGJ-contractile integral only in LT group (r = -0.79, P = 0.002 and r = -0.57, P = 0.051, respectively).

Conclusions

Following LT, acid reflux is characterized by a less hypotensive EGJ compared to controls with similar AET. The strongest correlation with AET after LT was found to be esophageal peristaltic vigor. These results add to the understanding of reflux after LT and may help tailor an individualized treatment plan.

The Relationship Between Vocal Fold Mobility Disorders and Ineffective Esophageal Motility

OBJECTIVE

Deglutition, speech production, and airway protection are extraordinarily complex, interrelated functions that are coordinated, in large part, by the motor and sensory innervation of CN X. Previous studies assessing the relationship between neurogenic voice disorders and dysphagia have focused on the risk of aspiration due to glottic insufficiency and the association of vocal fold hypomobility (VFH) with systemic neurologic disease. The purpose of this study was to investigate the relationship between VFH disorders and ineffective esophageal motility (IEM).

METHODS

Adult voice patients who underwent laryngeal electromyography (LEMG) and dual 24-hour pH impedance with high-resolution manometry (HRM) testing were included in the study. Subjects were assigned to one of two groups based on the presence or absence of moderate-to-severe RLN and/or SLN VFH (Mo-SLNH/RLNH) using results from six muscle LEMG tests. In subjects with Mo-SLNH/RLNH, there was 0-60% muscle recruitment on LEMG, whereas control subjects in the non-Mo-SLNH/RLNH group demonstrated 61-100% muscle recruitment. Analysis of mild-to-severe VFH (80% muscle recruitment or less) was also performed in a similar manner. The prevalence of IEM, defined using Chicago Classification Version 4.0 (CCv4.0), was compared between groups, as were HRM parameters.

RESULTS

One hundred sixty-two subjects were included (37.7% male/62.3% female, mean age of 43.88 ± 17.285). No differences in IEM prevalence were found when stratifying for cases of mild-to-severe VFH. However, there was significantly higher percentage of IEM in those with Mo-SLNH/RLNH. Mo-SLNH/RLNH subjects demonstrated higher rates of weak swallows and inefficient swallows, as well as lower IBP and UES residual pressures on HRM.

CONCLUSIONS

Patients with Mo-SLNH/RLNH demonstrated a significantly higher prevalence of IEM. Those with mild-to-severe VFH did not. Higher rates of ineffective and weak swallows, and lower IBP and UES residual pressures among Mo-SLNH/RLNH subjects suggest a possible connection between Mo-SLNH/RLNH and IEM disorders. These manometric differences were more prominent with sub-stratification of the Mo-SLNH/RLNH group by IEM. Additional research is advised.

Evaluation of Therapeutic Effect of Buspirone in Improving Dysphagia in Patients with GERD and Ineffective Esophageal Motility: A Randomized Clinical Trial

Background: Ineffective esophageal motility (IEM) is the most common esophageal motility disorder associated with low-to-moderate amplitude contractions in the distal esophagus in manometric evaluations. Despite recent new conceptions regarding the pathophysiology of esophageal motility and IEM, there are still no effective therapeutic interventions for the treatment of this disorder. This study aimed to investigate the effect of buspirone in the treatment of concomitant IEM and GERD. Methods and Materials: The present study was a randomized clinical trial conducted at the Imam Khomeini Hospital, Tehran. Patients with a history of gastroesophageal reflux disease and dysphagia underwent upper endoscopy to rule out any mechanical obstruction and were diagnosed with an ineffective esophageal motility disorder based on high-resolution manometry. They were given a package containing the desired medication(s); half of the packets contained 10 mg (for 30 days) of buspirone and 40 mg (for 30 days) of pantoprazole, and the other half contained only 40 mg (for 30 days) of pantoprazole. Dysphagia was scored based on the Mayo score, as well as a table of dysphagia severity. Manometric variables were recorded before and after the treatment. Results: Thirty patients (15 pantoprazole and 15 pantoprazole plus buspirone) were included. Females comprised 63.3% of the population, with a mean age of 46.33 ± 11.15. The MAYO score and resting LES pressure significantly changed after treatment. The MAYO and Swallowing Disorder Questionnaire scores significantly decreased after treatment in both groups of patients. Our results revealed that the post-intervention values of manometric variables differed significantly between the two groups after controlling for the baseline values of the variables. This analysis did not demonstrate the superiority of buspirone. Conclusion: Buspirone seems to have no superiority over PPI. Treatment with concomitant IEM and GERD using proton pump inhibitors improves the patient’s clinical condition and quality of life. However, adding buspirone to the treatment regimen did not appear to make a significant difference in patient treatment.

Can the marshmallow esophagram replace high-resolution manometry as an appropriate screening for esophageal motility prior to anti-reflux surgery?

BACKGOUND

The purpose of our study was to evaluate the use of minimally invasive Marshmallow Swallow Study (MSS) as a preoperative screening technique for patients and correlate marshmallow results with High Resolution Manometry (HRM) results and post-operative dysphagia following antireflux surgery.

METHODS

A retrospective electronic chart review of data on 61 adult patients undergoing MSS was completed. Patients were included if they completed the MSS as well as: HRM and/or antireflux surgery.

RESULTS

Sixty-one patients completed MSS. Of the 37 patients that completed HRM, 27 had abnormal results. 23 of these 27 patients who had abnormal results also failed MSS. The NPV for a failure on the MSS and abnormal HRM results is 0.767(p-value = 0.360). The PPV for a pass on the MSS and no post-operative dysphagia is 0.833 (p-value = 0.656).

CONCLUSIONS

MSS is an effective screening tool for ruling out major esophageal motility disorders and can prevent need for invasive HRM.

The Utility of the Marshmallow Barium Swallow Esophagogram for Investigation of Ineffective Esophageal Motility: A Systematic and Narrative Review

Objectives Current gold standard investigations to determine the pathology of ineffective esophageal motility (IEM) are invasive and resource-intensive. Marshmallow barium swallow esophagogram (MBSE) is emerging as a more feasible modality; however, our understanding of its role in the clinical setting is limited. Our aim was to appraise the current literature and describe the effectiveness and limitations of MBSE as a potential diagnostic tool when investigating the pathological cause of IEM.

Methods A search in PubMed was conducted on May 23, 2021. Search terms included “marshmallow” AND “barium.” We included all studies which examined MBSE in the context of esophageal disease. The primary outcome of interest was to characterize the use of MBSE in current literature.

Results A total of 12 studies were retrieved after initial search with 9 studies meeting final inclusion criteria. A total of 375 patients were included, with 296 patients (79%) having a relevant diagnosis or symptom prompting investigation with MBSE. The most common diagnoses included referral to a gastroenterology clinic for a barium swallow (44%), post-Angelchik insertion (23%), and dysphagia (13%). Esophageal disease was identified in both the MBSE and other screening tests in 63% participants, whereas in 27% participants abnormalities were only seen using the MBSE.

Conclusion There is currently limited high-quality evidence on the use of MBSE to diagnose IEM. Further large-scale studies comparing its use in patients with different pathologic causes of IEM and of older age are required to further delineate the optimal delivery of this emerging diagnostic modality.

Reduction and Resolution of a Hiatal Hernia Using Osteopathic Manipulative Treatment: A Case Report

Hiatal hernia is a condition where components of the abdominal cavity, most often a part of the stomach, penetrate through the diaphragm and into the chest cavity. The symptoms of hiatal hernias may differ secondary to their type and severity. The two main types of hiatal hernias are sliding and paraesophageal. Sliding hernias, which are more common and less of a cause for concern, are when the upper portion of the stomach and junction between the stomach and esophagus slides up into the thoracic cavity through a weakened diaphragm. These hernias account for the majority of all hiatal hernias, and their symptoms mimic those of gastroesophageal reflux disorder (GERD) due to laxity in the lower esophageal sphincter. Paraesophageal hernias occur when parts of the stomach and other abdominal organs protrude through the hiatus adjacent to an intact and in-place esophagus and stomach.

Obesity and old age are risk factors for hiatal hernias, but they can occur in patients of any age and gender. Although some hiatal hernias may be asymptomatic, patients with positive symptoms may complain of heartburn, regurgitation of liquids and food back into their mouths, dysphagia, or discomfort and pain in the stomach or esophagus. Hiatal hernias are preferentially diagnosed with proper imaging, mainly with an upper gastrointestinal barium study, or by upper gastrointestinal endoscopy. The treatment for hiatal hernias depends on their severity and surgical repairs, if needed, are mostly done laparoscopically.

In this case of a patient with a 3 cm hiatal hernia diagnosed with the help of esophagogastroduodenoscopy (EGD), the treatment did not require surgery. Instead, osteopathic manipulative treatment (OMT) was used to restore the functionality of the gastrointestinal tract and the placement of the gastroesophageal junction. The patient’s symptoms were found to have improved after the application of OMT alone, with no symptoms of hiatal hernia and resolution of her somatic dysfunctions. The results of this case study suggest that OMT can be effectively utilized to treat the symptoms of hiatal hernias and may also be effective as a curative method as well.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Glottic Insufficiency in the Vertical Plane in Patients With Unknown-Source Unilateral Vocal Fold Hypomobility

OBJECTIVE

To observe the laryngeal CT and strobe laryngoscopy signs of unilateral vocal fold hypomobility (UVFHM) in patients with well-closed glottises in the horizontal plane.

METHODS

A retrospective analysis was performed on 18 subjects with well-closed glottises in the horizontal plane using strobe laryngoscopy, 9 patients diagnosed with unilateral vocal fold hypomobility with an unknown etiology were enrolled in the UVFHM group, and 9 healthy matched subjects with symmetrical bilateral vocal fold movement were enrolled in the control group. Vertical plane distances of bilateral vocal folds and three-dimensional structural parameters of vocal folds were measured through laryngeal CT. Glottic insufficiency in the vertical plane and reflux findings scores (RFS) were assessed under laryngeal CT and strobe laryngoscopy. Reflux symptom index (RSI) were collected. SPSS25.0 software was used for statistical analysis.

RESULTS

The height differences in vertical plane and thicknesses of bilateral vocal folds in the UVFHM group were larger than those in the control (P < 0.05), while the length, width and subglottic convergence angle of the vocal folds were not statistically significant between the two groups (P > 0.05). In the UVFHM group, laryngeal CT showed that 77.78% of patients (7/9) had glottic insufficiency in the vertical plane, with height differences ranging from 0.3 to 1.9 mm and a mean of 0.76mm. However, strobe laryngoscopy showed that 33.33% (3/9) had glottic insufficiency in the vertical plane. The proportion of patients with glottic insufficiency in vertical plane in the UVFHM group was significantly higher than that in the control group (P < 0.05). RSI and RFS scores of the UVFHM group were higher than those of the control group (P < 0.05).

CONCLUSION

Glottic insufficiency in the vertical plane often occurred in patients with UVFHM with an unknown cause of hoarseness, so the presence of glottic insufficiency in the vertical plane should be considered when hoarseness is detected by clinicians. Laryngeal dynamic CT can enhance the diagnostic rate compared to strobe laryngoscopy. Unexplained UVFHM patients have higher RSI and RFS compared to control subjects, warranting further research about the relationship between UVFHM and laryngopharyngeal reflux.

Esophageal mucosal sensory nerves and potential mechanoreceptors in patients with ineffective esophageal motility

BACKGROUND

Ineffective esophageal motility (IEM) is the most common motility disorder. However, little is known about its pathophysiology. Vagal afferent nerves convey esophageal intraluminal bolus information to solitary nucleus, which is likely to be involved with esophageal primary and secondary peristalsis (SP). We hypothesized that altered mucosal sensory afferents underlie the pathogenesis of IEM.

METHODS

We prospectively collected esophageal biopsies from 38 patients with proton pump inhibitor-refractory reflux symptoms from January to December 2019. All patients underwent high-resolution manometry for the evaluation of primary and secondary peristalsis, and off-PPI 24-h impedance-pH studies. Biopsies were analyzed using immunohistochemistry for identification of calcitonin gene-related peptide-immunoreactive (CGRP-IR) nerves and qPCR for mRNA expression of potential mechanoreceptors.

KEY RESULTS

Overall 32 patients were finally analyzed which consisted of 11 patients with normal motility and 21 patients with IEM. The position of mucosal CGRP-IR nerves from the esophageal lumen did not differ between the two groups (the proximal esophagus (p = 0.52), the mid-esophagus (p = 0.92), the distal esophagus (p = 0.29)) with the similar reflux profile. No difference was seen in the position of CGRP-IR nerves between patients with successful triggering of SP and those unable to trigger SP. There was also no difference in mRNA expression of each potential mechanoreceptors (TRPA1, TRPV1, TRPV4, ASIC1, ASIC3) between the two groups.

CONCLUSIONS AND INFERENCES

Our study showed that mucosal sensory afferents nerve position and mRNA expression of potential mechanoreceptors did not correlate to weak esophageal contraction.

Contribution of tetrodotoxin-sensitive, voltage-gated sodium channels (NaV1) to action potential discharge from mouse esophageal tension mechanoreceptors

Action potentials depend on voltage-gated sodium channels (NaV1s), which have nine α subtypes. NaV1 inhibition is a target for pathologies involving excitable cells such as pain. However, because NaV1 subtypes are widely expressed, inhibitors may inhibit regulatory sensory systems. Here, we investigated specific NaV1s and their inhibition in mouse esophageal mechanoreceptors-non-nociceptive vagal sensory afferents that are stimulated by low threshold mechanical distension, which regulate esophageal motility. Using single fiber electrophysiology, we found mechanoreceptor responses to esophageal distension were abolished by tetrodotoxin. Single-cell RT-PCR revealed that esophageal-labeled TRPV1-negative vagal neurons expressed multiple tetrodotoxin-sensitive NaV1s: NaV1.7 (almost all neurons) and NaV1.1, NaV1.2, and NaV1.6 (in ∼50% of neurons). Inhibition of NaV1.7, using PF-05089771, had a small inhibitory effect on mechanoreceptor responses to distension. Inhibition of NaV1.1 and NaV1.6, using ICA-121341, had a similar small inhibitory effect. The combination of PF-05089771 and ICA-121341 inhibited but did not eliminate mechanoreceptor responses. Inhibition of NaV1.2, NaV1.6, and NaV1.7 using LSN-3049227 inhibited but did not eliminate mechanoreceptor responses. Thus, all four tetrodotoxin-sensitive NaV1s contribute to action potential initiation from esophageal mechanoreceptors terminals. This is different to those NaV1s necessary for vagal action potential conduction, as demonstrated using GCaMP6s imaging of esophageal vagal neurons during electrical stimulation. Tetrodotoxin-sensitive conduction was abolished in many esophageal neurons by PF-05089771 alone, indicating a critical role of NaV1.7. In summary, multiple NaV1 subtypes contribute to electrical signaling in esophageal mechanoreceptors. Thus, inhibition of individual NaV1s would likely have minimal effect on afferent regulation of esophageal motility.

Chicago Classification Update (v4.0): Technical review on diagnostic criteria for distal esophageal spasm

Distal esophageal spasm (DES) is defined as a manometric pattern of at least 20% of premature contractions in a context of normal esophago-gastric junction relaxation in a patient with dysphagia or non-cardiac chest pain. The definition of premature contraction requires the measurement of the distal latency and identification of the contractile deceleration point (CDP). The CDP can be difficult to localize, and alternative methods are proposed. Further, it is important to differentiate contractile activity and intrabolus pressure. Multiple rapid swallows are a useful adjunctive test to perform during high-resolution manometry to search for a lack of inhibition that is encountered in DES. The clinical relevance of the DES-manometric pattern was raised as it can be secondary to treatment with opioids or observed in patients referred for esophageal manometry before antireflux surgery in absence of dysphagia and non-cardiac chest pain. Further idiopathic DES is rare, and one can argue that when encountered, it could be part of type III achalasia spectrum. Medical treatment of DES can be challenging. Recently, endoscopic treatments with botulinum toxin and peroral endoscopic myotomy have been evaluated, with conflicting results while rigorously controlled studies are lacking. Future research is required to determine the role of contractile vigor and lower esophageal sphincter hypercontractility in the occurrence of symptoms in patients with DES. The role of impedance-combined high-resolution manometry also needs to be evaluated.

Spectrum of esophageal motility disorders in patients with liver cirrhosis

Disorders of esophageal motility have been described in patients with cirrhosis in a small number of studies. In this review, we aim to provide an overview of the available evidence on esophageal motility disorders in cirrhosis and their clinical implications. This review delves into the following concepts: (1) Gastroesophageal reflux disease is common in liver cirrhosis due to many mechanisms; however, when symptomatic it is usually nocturnal and has an atypical presentation; (2) Endoscopic band ligation is better than sclerotherapy in terms of its effect on esophageal motility and seems to correct dysmotilities resulting from the mechanical effect of esophageal varices; (3) Chronic alcoholism has no major effects on esophageal motility activity other than lower esophageal sphincter hypertension among those with alcoholic autonomic neuropathy; (4) An association between primary biliary cholangitis and scleroderma can be present and esophageal hypomotility is not uncommon in this scenario; and (5) Cyclosporin-based immunosuppression in liver transplant patients can have a neurotoxic effect on the esophageal myenteric plexus leading to reversible achalasia-like manifestations.

Esophageal Dysmotility is Common in Patients With Multiple System Atrophy

OBJECTIVES

Esophageal dysmotility (ED) in patients with multiple system atrophy (MSA) are poorly understood. This study aimed to investigate the prevalence of ED in patients with MSA and to assess the relationship of esophageal abnormalities with other clinical findings and characteristics in these patients.

METHODS

A retrospective chart review was conducted to identify patients with MSA and to compare them to the elderly controls without MSA (65+ years) who underwent a videofluorographic esophagram from 2014 to 2019. Disease type, disease severity, vocal fold mobility impairment, abnormal deglutitive proximal esophageal contraction (ADPEC), and intra-esophageal stasis (IES) were reviewed and compared between groups.

RESULTS

Thirty-seven patients with MSA were identified. The median age was 63 and 26 (70%) were male. These patients were matched to 22 elderly adults with presbylarynx but not MSA (median age 77, 68% male). In MSA patients, cerebellar variant type was predominant (59%), and ADPEC was recognized in 18 patients (49%). Disease severity level (P = 0.028) and existence of IES (P = 0.046) were associated with higher risks of developing ADPEC. The prevalence of IES was significantly higher in patients with MSA (95%) compared to controls without MSA (46%) (P < 0.001). Disease severity level and the existence of IES were significantly associated with the presence of ADPEC (p < 0.05).

CONCLUSION

ADPEC and IES were significantly more common in MSA than in elderly subjects without MSA. MSA severity is associated with the development of ADPEC. The data suggest that esophageal motility is predominantly affected in MSA.

LEVEL OF EVIDENCE

3 Laryngoscope, 131:832-838, 2021.

Neuronal Control of Esophageal Peristalsis and Its Role in Esophageal Disease

PURPOSE OF REVIEW

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

RECENT FINDINGS

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

Association of vesicoureteral reflux and gastroesophageal reflux disease in children: A population-based study

INTRODUCTION

Practitioners have anecdotally hinted at a possible association between gastroesophageal reflux disease (GERD) and vesicoureteral reflux (VUR). We sought to identify an association in diagnosis between GERD and VUR using a population-based dataset in a well-defined geographic area covered by a single-payer healthcare system.

METHODS

A retrospective review of individuals aged 0-16 years registered in the Nova Scotia Medical Service Insurance database from January 1997 to December 2012 was completed. Presence of GERD and VUR were ascertained based on billing codes. The baseline prevalence of GERD and VUR was calculated for this population for the same time period. Proportions of VUR patients with and without GERD were compared. The risk of being diagnosed with VUR in patients with GERD controlling for sex was calculated.

RESULTS

Of 404 300 patients identified, 6.6% had a diagnosis of GERD (n=27 092), 0.33% had a diagnosis of VUR (n=1348), and 0.08% were diagnosed with both (n=327). Among patients with VUR, the prevalence of GERD was 24.3% compared to 6.6% in patients without VUR (p<0.0001). Among patients with GERD, the prevalence of VUR was 1.2% compared to 0.27% in patients without (p<0.0001). The risk of being diagnosed with VUR was higher in the presence of GERD (odds ratio [OR] 4.49; 95% confidence interval [CI] 3.96-5.09; p<0.0001), irrespective of sex.

CONCLUSIONS

The odds of being diagnosed with VUR is more than 4.5 times higher in an individual with GERD. The clinical significance of this association remains to be explored.

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

BACKGROUND

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

PURPOSE

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

Evaluation of Esophageal Contraction Reserve Using HRM in Symptomatic Esophageal Disease

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

Esophageal transit scintigraphy in children: a user's guide and pictorial review

Technical and clinical aspects of esophageal transit scintigraphy in pediatric patients are reviewed via several illustrative cases that highlight its utility in evaluating primary and secondary esophageal motility disorders.

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.

In ineffective esophageal motility, failed swallows are more functionally relevant than weak swallows

BACKGROUND

Esophageal pressure topography (EPT) diagnosis of ineffective esophageal motility (IEM) can be non-specific with unclear clinical significance.

AIMS

To determine whether peristaltic vigor or lower esophageal sphincter (LES) integrity is associated with poor clearance and acid reflux in IEM.

METHODS

Bolus clearance on high-resolution impedance manometry (HRIM) and available reflux studies in patients with IEM were retrospectively reviewed. Bolus clearance was assessed using both line tracing and colored contour methods on HRIM. EPT parameters, bolus clearance, and acid reflux variables were explored.

KEY RESULTS

Eighty-eight patients with IEM were included. Bolus clearance occurred in 71% of all swallows, and 55.7% of patients had complete bolus transit (CBT, bolus clearance in ≥80% of swallows). Bolus clearance was impaired in swallows with distal contractile integral (DCI) <100 mmHg•cm•s compared to DCI 100-450 (0.43 vs 0.79, P < .0001). A cutoff at DCI 100 mmHg•cm•s was associated with clearance with an accuracy of 76% compared to 49% at DCI 450 (P = .0001 for both). A median DCI <100 was associated with a higher Eckardt score (9 vs 3, P = .03), and on reflux testing available in 47 patients, with abnormal acid exposure time (P = .002). Peristaltic reserve (PR) defined as (DCI of multiple rapid swallow/median DCI of wet swallows), integrated relaxation pressure, and resting lower esophageal sphincter pressure were not associated with clearance or acid exposure.

CONCLUSIONS & INFERENCES

Failed peristalsis, as defined by DCI <100 mmHg•cm•s, is associated with impaired bolus clearance and more severe dysphagia in IEM, and likely abnormal acid exposure.

Severity of ineffective esophageal motility is associated with utilization of skeletal muscle relaxant medications

BACKGROUND

Ineffective esophageal motility (IEM) is the most common finding on high-resolution esophageal manometry (HREM). The underlying mechanisms for IEM remain to be fully elucidated. The aim of this study was to determine if utilization of skeletal muscle relaxants is associated with IEM, and with more severe subtypes of the disorder.

METHODS

Patients with diagnosis of IEM were gender and age matched to patients with normal HREM. Demographic information, symptoms, endoscopic findings, medication usage and medical comorbidities were recorded. Patients with a diagnosis of IEM were divided into subgroups based on mean distal contractile integral (DCI) and percentage of ineffective swallows, and assessed for clinically significant differences among patients with varying severity of underlying IEM.

KEY RESULTS

A total of 118 patients were included in each group. There were no significant clinical differences between the group of patients with IEM and the group of patients with normal manometry. Within the group of IEM patients, those with mean DCI < 250 mm Hg/s/cm were more likely to be prescribed skeletal muscle relaxants (27.8% vs 11.0%, P = .044), and those using skeletal muscle relaxants had a larger mean percentage of ineffective swallows (81.1% vs 71.5%, P = .029). There were no significant differences across mean DCI subgroups in usage of any other medication, or in any of the demographic variables or disease comorbidities examined in this study.

CONCLUSIONS & INFERENCES

Use of skeletal muscle relaxants is associated with more severe IEM, which may suggest a causal association between this class of medications and weaker esophageal peristalsis.