The esophagogastric junction

Advanced Esophageal Endoscopy

Recent advancements in endoscopy, including high-definition imaging, virtual chromoendoscopy, and optical magnification, have enhanced our ability to visualize and diagnose certain esophageal diseases. Innovative endoscopic tools and procedures have been developed to broaden the scope of therapeutic options for treating patients with various esophageal conditions. This comprehensive review aims to elucidate the esophageal anatomy and major disorders from an endoscopist's perspective and explore recent advances in endoscopic treatment.

Gastroesophageal reflux disease in chronic obstructive pulmonary disease

Gastroesophageal reflux disease (GERD) is one of the most common comorbidities of chronic obstructive pulmonary disease (COPD). Decreased lower and upper esophageal sphincter pressures, esophageal dysmotility, high transdiaphragmatic pressure, and decreased saliva secretion have been implicated as mechanisms leading to the development of GERD in COPD. Clinically, comorbid GERD in COPD is reportedly associated with worse symptoms, quality of life, and lung function, as well as a high risk of exacerbations. Aspiration of regurgitation and the cholinergic-mediated esophagobronchial reflex play a significant role in the pathophysiology. Abnormal swallowing reflexes and discoordination of swallowing can worsen aspiration. The diagnosis of GERD is not based on a single criterion; however, various approaches, including questionnaires and endoscopic evaluations, can be widely applied in clinical settings. Due to the increased risk of esophageal and gastric cancers in patients with COPD, the threshold for endoscopic examination should be low. Acid inhibitory agents, such as proton pump inhibitors and histamine H2 receptor antagonists, and prokinetic agents, including mosapride and itopride, are clinically used to treat GERD. Endoscopic fundoplication can be performed in patients with GERD refractory to medical treatment. There is still insufficient evidence, but an increasing number of studies have suggested the clinical efficacy of treatment in patients with COPD and GERD. As GERD is an evaluative and treatable common disease, and access to evaluation and treatment is relatively easy, clinicians should provide adequate care for GERD in the management of COPD.

Saliva Production and Esophageal Motility Influence Esophageal Acid Clearance Related to Post-reflux Swallow-Induced Peristaltic Wave

BACKGROUND

The post-reflux swallow-induced peristaltic wave (PSPW) brings salivary bicarbonate to neutralize residual distal esophageal mucosal acidification.

AIMS

To determine if reduced saliva production and esophageal body hypomotility would compromise PSPW-induced pH recovery in the distal esophagus.

METHODS

In this multicenter retrospective cross-sectional study, patients with confirmed Sjogren's syndrome and scleroderma/mixed connective tissue disease (MCTD) who underwent high resolution manometry (HRM) and ambulatory pH-impedance monitoring off antisecretory therapy were retrospectively identified. Patients without these disorders undergoing HRM and pH-impedance monitoring for GERD symptoms were identified from the same time-period. Acid exposure time, numbers of reflux episodes and PSPW, pH recovery with PSPW, and HRM metrics were extracted. Univariate comparisons and multivariable analysis were performed to determine predictors of pH recovery with PSPW.

RESULTS

Among Sjogren's syndrome (n = 34), scleroderma/MCTD (n = 14), and comparison patients with reflux symptoms (n = 96), the scleroderma/MCTD group had significantly higher AET, higher prevalence of hypomotility, lower detected reflux episodes, and very low numbers of PSPW (p ≤ 0.004 compared to other groups). There was no difference in pH-impedance metrics between Sjogren's syndrome, and comparison patients (p ≥ 0.481). Proportions with complete pH recovery with PSPW was lower in Sjogren's patients compared to comparison reflux patients (p = 0.009), predominantly in subsets with hypomotility (p < 0.001). On multivariable analysis, diagnosis of Sjogren's syndrome, scleroderma/MCTD or neither (p = 0.014) and esophageal hypomotility (p = 0.024) independently predicted lack of complete pH recovery with PSPW, while higher total reflux episodes trended (p = 0.051).

CONCLUSIONS

Saliva production and motor function are both important in PSPW related pH recovery.

Narrative review of relationship between chronic cough and laryngopharyngeal reflux

Gastroesophageal reflux disease (GERD) as a possible cause of chronic cough is known for decades. However, more than 75% of patients with extraoesophageal symptoms do not suffer from typical symptoms of GERD like pyrosis and regurgitations and have negative upper gastrointestinal endoscopy. For such a condition term laryngopharyngeal reflux (LPR) was introduced and is used for more than two decades. Since the comprehensive information on relationship between chronic cough and LPR is missing the aim of this paper is to summarize current knowledge based on review of published information during last 13 years. Laryngopharyngeal reflux is found in 20% of patients with chronic cough. The main and recognized diagnostic method for LPR is 24-h multichannel intraluminal impedance-pH (MII-pH) monitoring, revealing reflux episodes irritating the upper and lower respiratory tract mucosa. The treatment of LPR should be initiated with dietary and lifestyle measures, followed by proton pump inhibitor (PPI) therapy and other measures. Despite progress, more research is needed for accurate diagnosis and targeted therapies. Key areas for exploration include biomarkers for diagnosis, the impact of non-acid reflux on symptom development, and the efficacy of new drugs. Further studies with a focused population, excluding other causes like asthma, and using new diagnostic criteria for LPR are essential. It's crucial to consider LPR as a potential cause of unexplained chronic cough and to approach diagnosis and treatment with a multidisciplinary perspective.

Incidental Discovery of Asymptomatic Stage IV Hiatal Hernia With Complete Gastric Thoracic Herniation: A Case Report

Hiatal hernia is a gastrointestinal disorder characterized by abnormal displacement of a portion of the stomach into the thoracic cavity. It has multiple stages ranging from type I-IV according to severity. The more severe the hernia, the more likely it will produce symptoms, and it would be unlikely for it to be asymptomatic. In this case report, we describe a rare situation in which a 79-year-old woman's type IV hiatal hernia was incidentally found after she suffered a mechanical fall.

Pathophysiology of gastro-oesophageal reflux disease: implications for diagnosis and management

Gastro-oesophageal reflux disease (GERD) is a common gastrointestinal disorder in which retrograde flow of gastric content into the oesophagus causes uncomfortable symptoms and/or complications. It has a multifactorial and partially understood pathophysiology. GERD starts in the stomach, where the refluxate material is produced. Following the trajectory of reflux, the failure of the antireflux barrier, primarily the lower oesophageal sphincter and the crural diaphragm, enables the refluxate to reach the oesophageal lumen, triggering oesophageal or extra-oesophageal symptoms. Reflux clearance mechanisms such as primary and secondary peristalsis and the arrival of bicarbonate-rich saliva are critical to prevent mucosal damage. Alterations of the oesophageal mucosal integrity, such as macroscopic oesophagitis or microscopic changes, determine the perception of symptoms. The intensity of the symptoms is affected by peripheral and central neural and psychological mechanisms. In this Review, we describe an updated understanding of the complex and multifactorial pathophysiology of GERD. It is now recognized that different GERD phenotypes have different degrees of reflux, severity of mucosal integrity damage and type, and severity of symptoms. These variations are probably due to the occurrence of a predominant pathophysiological mechanism in each patient. We also describe the main pathophysiological mechanisms of GERD and their implications for personalized diagnosis and management.

Latin American consensus on diagnosis of gastroesophageal reflux disease

BACKGROUND

Diagnosing gastroesophageal reflux disease (GERD) can be challenging given varying symptom presentations, and complex multifactorial pathophysiology. The gold standard for GERD diagnosis is esophageal acid exposure time (AET) measured by pH-metry. A variety of additional diagnostic tools are available. The goal of this consensus was to assess the individual merits of GERD diagnostic tools based on current evidence, and provide consensus recommendations following discussion and voting by experts.

METHODS

This consensus was developed by 15 experts from nine countries, based on a systematic search of the literature, using GRADE (grading of recommendations, assessment, development and evaluation) methodology to assess the quality and strength of the evidence, and provide recommendations regarding the diagnostic utility of different GERD diagnosis tools, using AET as the reference standard.

KEY RESULTS

A proton pump inhibitor (PPI) trial is appropriate for patients with heartburn and no alarm symptoms, but nor for patients with regurgitation, chest pain, or extraesophageal presentations. Severe erosive esophagitis and abnormal reflux monitoring off PPI are clearly indicative of GERD. Esophagram, esophageal biopsies, laryngoscopy, and pharyngeal pH monitoring are not recommended to diagnose GERD. Patients with PPI-refractory symptoms and normal endoscopy require reflux monitoring by pH or pH-impedance to confirm or exclude GERD, and identify treatment failure mechanisms. GERD confounders need to be considered in some patients, pH-impedance can identify supragrastric belching, impedance-manometry can diagnose rumination.

CONCLUSIONS

Erosive esophagitis on endoscopy and abnormal pH or pH-impedance monitoring are the most appropriate methods to establish a diagnosis of GERD. Other tools may add useful complementary information.

A Mechanics-Based Perspective on the Function of Human Sphincters During Functional Luminal Imaging Probe Manometry

Functional luminal imaging probe (FLIP) is used to measure cross-sectional area (CSA) and pressure at sphincters. It consists of a catheter surrounded by a fluid filled cylindrical bag, closed on both ends. Plotting the pressure-CSA hysteresis of a sphincter during a contraction cycle, which is available through FLIP testing, offers information on its functionality, and can provide diagnostic insights. However, limited work has been done to explain the mechanics of these pressure-CSA loops. This work presents a consolidated picture of pressure-CSA loops of different sphincters. Clinical data reveal that although sphincters have a similar purpose (controlling the flow of liquids and solids by opening and closing), two different pressure-CSA loop patterns emerge: negative slope loop (NSL) and positive slope loop (PSL). We show that the loop type is the result of an interplay between (or lack thereof) two mechanical modes: (i) neurogenic mediated relaxation of the sphincter muscle or pulling applied by external forces, and (ii) muscle contraction proximal to the sphincter which causes mechanical distention. We conclude that sphincters which only function through mechanism (i) exhibition NSL whereas sphincters which open as a result of both (i) and (ii) display a PSL. This work provides a fundamental mechanical understanding of human sphincters. This can be used to identify normal and abnormal phenotypes for the different sphincters and help in creating physiomarkers based on work calculation.

Selective dysfunction of the crural diaphragm in patients with chronic restrictive and obstructive lung disease

BACKGROUND

Gastroesophageal reflux (GER) is known to be associated with chronic lung diseases. The driving force of GER is the transdiaphragmatic pressure (Pdi) generated mainly by costal and crural diaphragm contraction. The latter also enhances the esophagogastric junction (EGJ) pressure to guard against GER.

METHODS

The relationship between Pdi and EGJ pressure was determined using high resolution esophageal manometry in patients with interstitial lung disease (ILD, n = 26), obstructive lung disease (OLD, n- = 24), and healthy subjects (n = 20).

KEY RESULTS

The patient groups did not differ with respect to age, gender, BMI, and pulmonary rehabilitation history. Patients with ILD had significantly higher Pdi but lower EGJ pressures as compared to controls and OLD patients (p < 0.001). In control subjects, the increase in EGJ pressure at all-time points during inspiration was greater than Pdi. In contrast, the EGJ pressure during inspiration was less than Pdi in 14 patients with ILD and 7 patients with OLD. The drop in EGJ pressure was usually seen after the peak Pdi in ILD group (p < 0.0001) and before the peak Pdi in OLD group, (p = 0.08). Nine patients in the ILD group had sliding hiatus hernia, compared to none in control subjects (p = 0.003) and two patients in the OLD, (p = 0.04).

CONCLUSIONS AND INFERENCES

A higher Pdi and low EGJ pressure, and dissociation between Pdi and EGJ pressure temporal relationship suggests selective dysfunction of the crural diaphragm in patients with chronic lung diseases and may explain the higher prevalence of GERD in ILD as seen in previous studies.

Clinical characteristics of absent contractility and ineffective esophageal motility: a multicenter study in Japan

BACKGROUND AND AIM

Absent contractility (AC) and ineffective esophageal motility (IEM) are esophageal hypomotility disorders diagnosed using high-resolution manometry (HRM). Patient characteristics and disease course of these conditions and differential diagnosis between AC and achalasia are yet to be elucidated.

METHODS

A multicenter study involving 10 high-volume hospitals was conducted. Starlet HRM findings were compared between AC and achalasia. Patient characteristics including underlying disorders and disease courses were analyzed in AC and IEM.

RESULTS

Fifty-three patients with AC and 92 with IEM were diagnosed, while achalasia was diagnosed in 1784 patients using the Chicago classification v3.0 (CCv3.0). The cut-off integrated relaxation pressure (IRP) value at 15.7 mmHg showed maximum sensitivity (0.80) and specificity (0.87) for differential diagnosis of AC from type I achalasia. While most ACs were based on systemic disorders such as scleroderma (34%) and neuromuscular diseases (8%), 23% were sporadic cases. The symptom severity of AC was not higher than that of IEM. Regarding the diagnosis of IEM, the more stringent CCv4.0 excluded 14.1% of IEM patients than the CCv3.0, although patient characteristics did not change. In patients with the hypomotile esophagus, concomitance of reflux esophagitis was associated with low distal contractile integral and IRP values. AC and IEM transferred between each other, paralleling with the underlying disease course, although no transition to achalasia was observed.

CONCLUSION

A successful determination of the optimal cut-off IRP value was achieved using the starlet HRM system to differentiate AC and achalasia. Follow-up HRM is also useful for differentiating AC from achalasia. Symptom severity may depend on underlying diseases instead of hypomotility severity.

Study of gastroesophageal reflux. Interpretation of functional tests in the obese patient

Overweight and obesity are a public health problem and in 1997 obesity was recognized as a global epidemic by the World Health Organization (WHO). Overweight and obesity affect almost 60% of adults and one in three children in Europe according to the most recent WHO report. Objectively, gastroesophageal reflux disease (GERD) is defined as the presence of characteristic esophageal mucosal damage assessed by endoscopy and/or the demonstra-tion of pathological acid exposure by reflux monitoring studies. The prevalence of GERD is increased in obese patients In overweight and obese patients, the clinical symptoms of GERD are especially present in the supine position and this correlates with more frequent episodes of nocturnal reflux in the 24-h pH monitoring, there is also an increase in the number of refluxes with content acid. In the population with symptoms, digestive endoscopy detects data of erosive esophagitis in 50% of patients, while 24-h pH-impedanciometry diagnoses 92% of patients with non-erosive reflux disease (NERD) The presence of persistent GERD in the mucosa affects esophageal motility and patients may develop ineffective esophageal motility-type disorders, so we will review the interpre-tation of the functional tests that determine motility, which is esophageal manometry, and those that determine reflux gastroesophageal, acid and non-acid, which is the pH measure-ment with or without 24-h impedanciometry.

Gastro‑oesophageal reflux disease in liver cirrhosis: Possible pathogenesis and clinical intervention (Review)

Oesophageal variceal bleeding is a common complication of decompensated liver cirrhosis (LC). Some studies have reported that reflux oesophagitis (RE) is a risk factor for upper gastrointestinal bleeding, and greatly impacts the quality of life. However, the frequency and mechanism of gastro-oesophageal reflux disease (GERD) in LC remain unclear. The present review explored the possible pathogenesis, and analysed the advantages and disadvantages of the interventional measures and the need for implementation of these measures. By combining the comprehensive terms associated with LC, GERD and RE, EMBASE, Medline/PubMed and the Cochrane Library were systematically searched. The underlying pathological mechanism of GERD in LC was summarized: Transient relaxation of the lower oesophageal sphincter, delayed gastric emptying, increased intra-abdominal pressure, increased intragastric pressure and excessive nitric oxide production destroyed the 'anti-reflux barrier', causing gastric content reflux. Proton pump inhibitors (PPIs) have been widely used empirically to lower the risk of oesophageal venous rupture and bleeding. However, long-term use of acid inhibitors in patients with LC may induce complications, such as spontaneous bacterial peritonitis. The metabolic half-life of PPIs is prolonged in patients with severe liver function impairment. Therefore, the indications for using acid inhibitors lack clarity. However, after endoscopic oesophageal variceal eradication, additional benefits may be gained from the long-term use of PPIs in small doses.

Long versus short peroral endoscopic myotomy for the treatment of achalasia: results of a non-inferiority randomised controlled trial

OBJECTIVE

Peroral endoscopic myotomy (POEM) has become standard treatment for achalasia with comparable efficacy to surgery. In most of published series, the length of myotomy is 12-13 cm. Shorter cuts could have the advantage of shorter procedure time and possibly reduced gastro-oesophageal reflux disease (GORD) rate.

DESIGN

This single-centre, patient-blinded, randomised, non-inferiority clinical trial included 200 patients, who were randomly allocated, to receive either a long-POEM (13 cm; 101 patients) or a short-POEM (8 cm; 99 patients). Primary outcome was defined as an Eckardt symptom score of ≤3 at 24 months after the procedure; a non-inferiority design was chosen with an accepted success range of 6% between the two treatments. Secondary outcomes included operating time, complication rate, postoperative manometry, GORD rate and quality of life.

RESULTS

In the intention-to-treat analysis, clinical success rates were 89.1% in the long-POEM and 98.0% in the short-POEM group, resulting in an absolute between-group difference of -8.9% (90% CI -14.5 to -3.3).Procedure time was significantly reduced in the short-POEM as compared with the long-POEM group (40 vs 50 min, p<0.0001). Severe adverse events occurred in one patient in both groups.No differences were observed in postoperative GORD: acid exposure >6% on pH monitoring study at 6 months was seen in 34.3% (long-POEM) vs 31.1% (short-POEM), while endoscopic oesophagitis was diagnosed in 37.6% vs 51.5% at 6 months and in 21% vs 24.5% at 24 months. Regular proton pump inhibitor use was not different either (36.8% vs 37.5%).

CONCLUSIONS

Our study demonstrates non-inferiority of a shorter cut length of POEM as compared with the standard treatment, which saved some procedural time. GORD rate was not reduced by reducing cutting length.

TRIAL REGISTRATION NUMBER

NCT03450928.

A mechanics-based perspective on the function of the esophagogastric junction during functional luminal imaging probe manometry

The esophagogastric junction (EGJ) is located at the distal end of the esophagus and acts as a valve allowing swallowed food to enter the stomach and preventing acid reflux. Irregular weakening or stiffening of the EGJ muscles results in changes to its opening and closing patterns which can progress into esophageal disorders. Therefore, understanding the physics of the opening and closing cycle of the EGJ can provide mechanistic insights into its function and can help identify the underlying conditions that cause its dysfunction. Using clinical functional lumen imaging probe (FLIP) data, we plotted the pressure-cross-sectional area loops at the EGJ location and distinguished two major loop types-a pressure dominant loop and a tone dominant loop. In this study, we aimed to identify the key characteristics that define each loop type and determine what causes the inversion from one loop to another. To do so, the clinical observations are reproduced using 1D simulations of flow inside a FLIP device located in the esophagus, and the work done by the EGJ wall over time is calculated. This work is decomposed into active and passive components, which reveal the competing mechanisms that dictate the loop type. These mechanisms are esophageal stiffness, fluid viscosity, and the EGJ relaxation pattern.

Transient Hiatal Separation During Straight Leg Raise Can Predict Reflux Burden in Gastroesophageal Reflux Disease Patients With Ineffective Esophageal Motility

Background/Aims

Straight leg raise (SLR) can be utilized to evaluate the integrity of the esophagogastric junction during high-resolution manometry (HRM). We aim to assess the value of transient hiatal separation during SLR in symptomatic reflux patients.

Methods

Consecutive reflux patients undergoing esophageal HRM and pH monitoring were included. Transient hiatal separation was defined by a ≥ 1 cm separation between the lower esophageal sphincter and crural diaphragm during SLR. We compared esophageal motor patterns and reflux monitoring parameters between patients with normal, transiently abnormal and consistently abnormal esophagogastric junction morphology during SLR.

Results

Of 85 (56.3% female, mean age: 46.7 ± 12.3 years) completed SLR, esophagogastric junction morphology was normal in 31 (36.5%), transient hiatal separation in 19 (22.3%), and consistently hiatal hernia in 35 (41.2%). The values of total acid exposure time (P = 0.016), longest acid reflux episodes (P = 0.024), and DeMeester scores (P = 0.016) were higher in hiatal hernia compared to patients with non-transient hiatal separation, but there were no differences between those with and without transient hiatal separation. Within ineffective esophageal motility, the presence of transient hiatal separation during SLR significantly associated with a higher total acid exposure time (P = 0.014), higher DeMeester scores (P = 0.019), higher total acid reflux events (P = 0.037), and higher longest acid reflux episodes (P = 0.006).

Conclusion

Our work suggests that SLR may have value as a provocative test during HRM, and future outcome studies are warranted to elucidate the clinical relevance of motor abnormalities depicted from SLR.

Anatomical features for an adequate choice of the experimental animal model in biomedicine: III. Ferret, goat, sheep, and horse

The anatomical characteristics of each of the many species today employed in biomedical research are very important when selecting the correct animal model(s), especially for conducting translational research. In previous papers, these features have been considered for fish (D'Angelo et al. Ann. Anat, 2016, 205:75), the most common laboratory rodents, rabbits, and pigs (Lossi et al. 2016). I here follow this line of discussion by dealing with the importance of proper knowledge of ferrets, goats, sheep, and horses' main anatomical features in translational research.

Safety and effectiveness of sling fiber preservation POEM to reduce severe post-procedural erosive esophagitis

BACKGROUND

Peroral endoscopic myotomy (POEM) is standard treatment for achalasia. Gastroesophageal reflux disease (GERD) after POEM has been an important challenge since the early days of POEM implementation. The esophagogastric junction anti-reflux barrier consists of internal lower esophageal sphincter (LES) (i.e., intrinsic muscles of distal esophagus with sling fibers) and external LES (crural diaphragm and phrenoesophageal ligament anchors the distal esophagus to the crural diaphragm). During conventional POEM, the entire internal LES is unintentionally dissected. Preservation of the sling fiber may reduce post-POEM GERD, but its safety and effectiveness have been unclear. In this study, we investigated the safety and effectiveness of sling fiber preservation POEM (SP-POEM) for reducing severe post-procedural erosive esophagitis.

METHODS

We analyzed data of 236 patients who underwent POEM; of these, 203 patients underwent posterior myotomy without (Group 1) or with attempted (Group 2) sling fiber preservation. Group 1 (N = 79; sling fiber excision, N = 68) and Group 2 (N = 90; sling fiber preservation, N = 81) were compared. Post-procedural erosive esophagitis (Los Angeles classification) were assessed and the area (direction and length) of mucosal break was also investigated. The gastroesophageal flap valve was evaluated by Hill's classification.

RESULTS

Severe erosive esophagitis exceeding grade C (Los Angeles classification) occurred in 44.1% of patients (30/68) in Group 1 and in 18.5% of patients (15/81) in Group 2. In mapping of erosive esophagitis, mucosal breaks appeared widely in all directions in Group 1; they tended to be limited in Group 2 (especially in the 2 o'clock direction). Assessment using the Hill's classification showed that the gastroesophageal flap valve was preserved after SP-POEM.

CONCLUSION

SP-POEM is safe and effective, with a success rate of 90%. The rate of severe erosive esophagitis can be decreased by preserving sling fibers.

The effect of age and sex on esophageal hiatal surface area among normal North American adults using multidetector computed tomography

The size of the esophageal hiatus is clinically important for preserving the integrity of the lower esophageal sphincter mechanism. The purpose of this study was to systematically establish the mean hiatal surface area (HSA) for normal North American adults under physiologic conditions and assess the relationship between sex and age on HSA. Multi-Detector Computer Tomogram (MDCT) images of the esophageal hiatus in 119 healthy adult subjects (61 males and 58 females with an age range of 24-88 years) were retrospectively analyzed using the multi-planar reconstruction (MPR) technique to directly measure their hiatal length (long axis), width (short axis) and surface area at end inspiration. The mean HSA for males was 2.88 cm², with a standard deviation of 0.74 cm². The mean HSA for females was 2.51 cm², with a standard deviation of 0.68 cm². There was a statistically significant difference in HSA between males and females (p = 0.0053); however, there was no statistically significant difference between the HSA among different age groups (p = 0.8439). Similarly, significant differences between males and females were demonstrated in both the length (p = 0.0263) and width (p = 0.0311) measurements, but there was no evidence of an association of these parameters with age. For the first time, the normal size of the hiatus at end inspiration has been established noninvasively for a population of healthy adults from MDCT images.

Endoscopic Management of GERD

Gastroesophageal reflux disease (GERD) has consistently been the most frequently diagnosed gastrointestinal malady in the USA. The mainstay of therapy has traditionally been medical management, including lifestyle and dietary modifications as well as antacid medications. In those patients found to be refractory to medical management or with a contraindication to medications, the next step up has been surgical anti-reflux procedures. Recently, though innovative advancements in therapeutic endoscopy have created numerous options for the endoscopic management of GERD, in this review, we discuss the various endoscopic therapy options, as well as suggested strategies we use to recommend the most appropriate therapy for patients.

GASTROESOPHAGEAL REFLUX DISEASE: A PRACTICAL APPROACH

Gastroesophageal reflux disease (GERD) presents typical manifestations such as heartburn and/or regurgitation as well as atypical manifestations such as throat symptoms, laryngitis, hoarseness, chronic cough, asthma, and sleep alterations. There are two phenotypes of the disease: erosive GERD, when erosions are identified by upper digestive endoscopy, and non-erosive GERD, when the esophageal mucosa presents a normal endoscopic aspect. Relevant clinical findings are usually absent in the physical examination, but it should be highlighted that obesity is an important aggravating factor of reflux. The treatment is established based on clinical findings and, according to the clinical situation, on complementary exams such as upper digestive endoscopy. In dubious cases where a precise diagnosis is required, the indicated test is esophageal pHmetry or impedance-pHmetry. Clinical treatment is divided into behavioral/dietary measures and pharmacological measures. Most patients benefit from clinical treatment, but surgical treatment may be indicated in the presence of a larger hiatal hernia and complications of the disease.

Assessment of esophagogastric junction morphology by dynamic real-time MRI: comparison of imaging features to high-resolution manometry

Purpose

To assess the esophagogastric junction (EGJ) on real-time MRI and compare imaging parameters to EGJ morphology on high-resolution manometry (HRM).

Methods

A total of 105 of 117 eligible patients who underwent real-time MRI and high-resolution manometry for GERD-like symptoms between 2015 and 2018 at a single center were retrospectively evaluated (male n = 57; female n = 48; mean age 52.5 ± 15.4 years). Real-time MRI was performed at a median investigation time of 15 min (1 frame/40 ms). On HRM, EGJ morphology was assessed according to the Chicago classification of esophageal motility disorders. Real-time MRI was performed at 3 T using highly undersampled radial fast low-angle shot acquisitions with NLINV image reconstruction. A 10 mL pineapple juice bolus served as oral contrast agent at supine position. Real-time MRI films of the EGJ were acquired during swallowing events and during Valsalva maneuver. Anatomic and functional MRI parameters were compared to EGJ morphology on HRM.

Results

On HRM, n = 42 patients presented with EGJ type I (40.0%), n = 33 with EGJ type II (31.4%), and n = 30 with EGJ type III (28.6%). On real-time MRI, hiatal hernia was more common in patients with EGJ type III (66.7%) than in patients with EGJ type I (26.2%) and EGJ type II (30.3%; p < 0.001). Sliding hiatal hernia was more frequent in patients with EGJ type II (33.3%) than in patients with EGJ type III (16.7%) and EGJ type I (7.1%; p = 0.017). The mean esophagus–fundus angle of patients was 85 ± 31° at rest and increased to 101 ± 36° during Valsalva maneuver.

Conclusion

Real-time MRI is a non-invasive imaging method for assessment of the esophagogastric junction. Real-time MRI can visualize dynamic changes of the EGJ during swallowing events.

Supplementary Information

The online version contains supplementary material available at 10.1007/s11604-021-01210-9.

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.

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

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

Current Advancement on the Dynamic Mechanism of Gastroesophageal Reflux Disease

Gastroesophageal reflux disease (GERD) is a common clinical disease associated with upper gastrointestinal motility disorders. Recently, with improvements in living standards and changes in lifestyle and dietary habits, the incidence of GERD has been increasing yearly. However, the mechanism of GERD has not been fully elucidated due to its complex pathogenesis, and this had led to unsatisfactory therapeutic outcomes. Currently, the occurrence and development of GERD involve multiple factors. Its pathogenesis is mainly thought to be related to factors, such as lower esophageal sphincter pressure, transient lower esophageal sphincter relaxation, crural diaphragmatic dysfunction, hiatus hernia, and impaired esophageal clearance. Therefore, explaining the pathogenesis of GERD more clearly and systematically, exploring potential and effective therapeutic targets, and choosing the best treatment methods have gradually become the focus of scholars' attention. Herein, we reviewed current advancements in the dynamic mechanism of GERD to better counsel patients on possible treatment options.

Esophagogastric junction contractile integral abnormalities in patients with proton pump inhibitor-refractory symptoms

OBJECTIVES

Esophagogastric junction contractile integral (EGJ-CI) is a novel indicator to evaluate quantitatively the esophagogastric junction (EGJ) barrier function. We aimed to assess the role of EGJ-CI in patients with refractory gastroesophageal reflux disease (GERD) symptoms and the correlation between EGJ-CI and impedance-pH monitoring characteristics.

METHODS

In total 82 patients with proton pump inhibitors (PPIs)-refractory gastroesophageal reflux symptoms (heartburn or regurgitation) were enrolled. These patients were further divided into two groups based on their EGJ-CI value (39 mmHg·cm). The mean nocturnal baseline impedance (MNBI) was measured to explore its association with EGJ-CI.

RESULTS

The median EGJ-CI in patients with PPI-refractory symptoms was 30.8 mmHg·cm. EGJ-CI was inversely correlated with acid exposure time and reflux episodes; while it was positively correlated with MNBI, distal contractile integral, lower esophageal sphincter basal pressure and integrated relaxation pressure. Patients were further divided into the high (n = 27) and low (n = 55) EGJ-CI groups using a cut-off value of 39.0 mmHg·cm. Patients with a low EGJ-CI had a lower MNBI level than those with a high EGJ-CI (2703 Ω vs 3545 Ω, P = 0.034).

CONCLUSIONS

In patients with PPIs-refractory symptoms, EGJ-CI is associated with acid exposure and conventional high-resolution manometry parameters. EGJ-CI may play an important role in the diagnosis and treatment of patients with refractory GERD.

Endoscopic Prediction for Acid Reflux in Patients without Hiatus Hernia

Background/Aims

A diagnosis of gastroesophageal reflux disease is challenging in patients who have reflux symptoms but do not respond to proton pump inhibitors nor have reflux esophagitis and hiatal hernia (HH) on endoscopy. This study examined the predictive role of the endoscopic findings, including the flap valve grade for pathologic acid exposure (PAE) to establish an endoscopic prediction model in patients with neither reflux esophagitis nor HH.

Methods

Five hundred seventy-eight patients who underwent upper endoscopy and 24 hours pH monitoring for reflux esophageal symptoms without evidence of reflux esophagitis and HH were analyzed. The gastroesophageal flap valve (GEFV), esophageal metaplasia, and chronic atrophic gastritis were assessed. The association between the endoscopic parameters and PAE was evaluated.

Results

Four hundred ninety-four patients were enrolled. The most common complaint was chest discomfort (42.3%) followed by globus (31.8%), dysphagia (7.9%), and heartburn (7.7%). PAE was present in 43 patients (8.7%). Multivariable analysis revealed PAE to be associated with the GEFV grade (p<0.001) and inversely associated with the chronic atrophic gastritis grade (p=0.005). Using these features, a predictive model was established and showed an area under the receiver operating characteristic curve of 0.705 (95% CI 0.619-0.790). The cutoff value of 12.0 had a sensitivity and specificity of 44.0% and 84.0%, respectively.

Conclusions

A loosened GEFV is associated with a risk of PAE in patients with neither reflux esophagitis nor HH, while atrophic gastritis is preventive. On the other hand, the endoscopic predictive model revealed a low sensitivity for detecting PAE. Thus, reflux testing needs to be performed further when gastroesophageal reflux disease is suspected, even without endoscopic evidence.

Hiatal Hernia Associated with Higher Odds of Dysplasia in Patients with Barrett's Esophagus

BACKGROUND

Patients with Barrett's esophagus (BE) are more likely to have associated hiatal hernia (HH) compared to the general population. Studies show that HH are typically longer and wider in patients with BE.

AIMS

To determine whether patients with HH have associated increased odds of coexistence of BE by examining inpatient prevalence, as well as determining other inpatient outcomes.

METHODS

This was a case-control study using the NIS 2016, the largest public inpatient database in the USA. All patients with ICD10CM codes for BE were included. None were excluded. The primary outcome was determining the association between BE and HH in hospitalized patients, stratified by grade of dysplasia. Secondary outcomes included measuring use of endoscopic ablation in patients with BE and HH compared to patients with BE and no HH, determining the degree of association between HH and esophagitis in patients with or without BE, as well as the association between esophagitis and dysplasia in patients with BE and HH.

RESULTS

A total of 118,750 patients with BE were identified, of which 24,030 had associated HH. Adjusted odds of having associated BE in patients with HH was 10.9 (p < 0.01) compared to patients without HH. Patients with HH also displayed significantly higher odds of both low-grade dysplasia (aOR 34.5, p < 0.01) and high-grade dysplasia (aOR 14.7, p < 0.01). For secondary outcomes, the odds of undergoing ablation for BE was higher 4.77 (p < 0.01) in patients with HH.

CONCLUSIONS

Patients with HH have significantly higher odds of having associated BE, regardless of the level of dysplasia. Furthermore, the odds of undergoing ablation are much higher, likely reflecting higher odds of dysplasia. This highlights the importance of BE in patients with HH, and potentially consider these patients as higher risk.

Gastro-oesophageal reflux disease

Gastro-oesophageal reflux disease (GERD) is a common disorder in adults and children. The global prevalence of GERD is high and increasing. Non-erosive reflux disease is the most common phenotype of GERD. Heartburn and regurgitation are considered classic symptoms but GERD may present with various atypical and extra-oesophageal manifestations. The pathophysiology of GERD is multifactorial and different mechanisms may result in GERD symptoms, including gastric composition and motility, anti-reflux barrier, refluxate characteristics, clearance mechanisms, mucosal integrity and symptom perception. In clinical practice, the diagnosis of GERD is commonly established on the basis of response to anti-reflux treatment; however, a more accurate diagnosis requires testing that includes upper gastrointestinal tract endoscopy and reflux monitoring. New techniques and new reflux testing parameters help to better phenotype the condition. In children, the diagnosis of GERD is primarily based on history and physical examination and treatment vary with age. Treatment in adults includes a combination of lifestyle modifications with pharmacological, endoscopic or surgical intervention. In refractory GERD, optimization of proton-pump inhibitor treatment should be attempted before a series of diagnostic tests to assess the patient's phenotype.

Genetically engineered mouse models of esophageal cancer

BACKGROUND

Esophageal cancer is the most common cause of cancer-related death worldwide with a diverse geographical distribution, poor prognosis, and diagnosis in advanced stages of the disease. Identification of the mechanisms involved in esophageal cancer development is evaluative to improve outcomes for patients. Genetically engineered mouse models (GEMMs) of cancer provide the physiologic, molecular, and histologic features of the human tumors to determine the pathogenesis and treatments for cancer, hence exhibiting a source of tremendous potential for oncology research. The advancement of cancer modeling in mice has improved to the extent that researchers can observe and manipulate the disease process in a specific manner. Despite the significant differences between mice and humans, mice can be great models for human oncology researches due to similarities between them at the molecular and physiological levels. Due to most of the existing esophageal cancer GEMMs do not propose an ideal system for pathogenesis of the disease, genetic risks, and microenvironment exposure, so identification of challenges in GEM modeling and well-developed technologies are required to obtain the most value for patients. In this review, we describe the biology of human and mouse, followed by the exciting esophageal cancer mouse models with a discussion of applicability and challenges of these models for generating new GEMMs in future studies.

The Cough Reflex: The Janus of Respiratory Medicine

In clinical practice, we commonly face adversity when encountering dysfunction of the cough reflex. Similar to ancient Roman deity Janus, it often presents with one of two opposing "faces". Continual aberrant activation of the cough reflex, also known as chronic cough, can cause great detriment to quality of life and many of these patients are left misdiagnosed and undertreated. In contrast, loss of normal functioning of the cough reflex is the cause of a significant proportion of mortality in the elderly, primarily through the development of aspiration pneumonia. In this review we discuss both hyper- and hypo-activation of the cough reflex and how airway reflux and chronic aspiration may be involved in the aetiology and sequalae of both disease states. We detail the physiological and pharmacological mechanisms involved in cough, and how the recent development of P2X3 receptor antagonists may lead to the first pharmaceutical agent licensed for chronic cough. The treatment and prevention of loss of the cough reflex, which has been largely neglected, is also discussed as novel low-cost interventions could help prevent a number of hospital and domiciliary deaths from both acute and chronic aspiration.

Esophagogastric junction morphology and contractile integral on high-resolution manometry in asymptomatic healthy volunteers: An international multicenter study

BACKGROUND

Esophagogastric junction contractile integral (EGJ-CI) and EGJ morphology are high-resolution manometry (HRM) metrics that assess EGJ barrier function. Normative data standardized across world regions and HRM manufacturers are limited.

METHODS

Our aim was to determine normative EGJ metrics in a large international cohort of healthy volunteers undergoing HRM (Medtronic, Laborie, and Diversatek software) acquired from 16 countries in four world regions. EGJ-CI was calculated by the same two investigators using a distal contractile integral-like measurement across the EGJ for three respiratory cycles and corrected for respiration (mm Hg cm), using manufacturer-specific software tools. EGJ morphology was designated according to Chicago Classification v3.0. Median EGJ-CI values were calculated across age, genders, HRM systems, and regions.

RESULTS

Of 484 studies (28.0 years, 56.2% F, 60.7% Medtronic studies, 26.0% Laborie, and 13.2% Diversatek), EGJ morphology was type 1 in 97.1%. Median EGJ-CI was similar between Medtronic (37.0 mm Hg cm, IQR 23.6-53.7 mm Hg cm) and Diversatek (34.9 mm Hg cm, IQR 22.1-56.1 mm Hg cm, P = 0.87), but was significantly higher using Laborie equipment (56.5 mm Hg cm, IQR 35.0-75.3 mm Hg cm, P < 0.001). 5^th percentile EGJ-CI values ranged from 6.9 to 12.1 mm Hg cm. EGJ-CI values were consistent across world regions, but different between manufacturers even within the same world region (P ≤ 0.001). Within Medtronic studies, EGJ-CI and basal LESP were similar in younger and older individuals (P ≥ 0.3) but higher in women (P < 0.001).

CONCLUSIONS

EGJ morphology is predominantly type 1 in healthy adults. EGJ-CI varies widely in health, with significant gender influence, but is consistent within each HRM system. Manufacturer-specific normative values should be utilized for clinical HRM interpretation.

Gastroesophageal Reflux Disease in the Young Population and Its Correlation With Anxiety and Depression

Introduction Stress and anxiety may disrupt normal GI function and lead to several GI disorders, including gastroesophageal reflux disease (GERD). In this study, we aimed to predict the prevalence of GERD in young patients and its association with anxiety and depression. Material and Methods This cross-sectional study enrolled 2,500 participants from the general public, with an age range of 18 to 40 years. Diagnosis of GERD was made via the Frequency Scale for the Symptoms of GERD (FSSG) questionnaire. The Hospital Anxiety and Depression Scale (HADS) was used to assess anxiety and depression. Results GERD was diagnosis in 401 (16.0%) participants. Anxiety was significantly more common in participants with GERD compared to participants without GERD (40.3% vs. 19.5%; p < 0.01). Similarly, participants with GERD had a higher prevalence of depression compared to participants without GERD (42.6% vs. 18.3%; p < 0.01). Conclusion GERD is highly prevalent among the young population. Anxiety and depression are significantly more prevalent in patients with GERD. Hence, the young population must be thoroughly screened for GERD to minimize the risk of long-term complications. Furthermore, patients diagnosed with GERD should be screened for depression and anxiety.

Estimation of mechanical work done to open the esophagogastric junction using functional lumen imaging probe panometry

In this study, we quantify the work done by the esophagus to open the esophagogastric junction (EGJ) and create a passage for bolus flow into the stomach. Work done on the EGJ was computed using functional lumen imaging probe (FLIP) panometry. Eighty-five individuals underwent FLIP panometry with a 16-cm catheter during sedated endoscopy including asymptomatic controls (n = 14), 45 patients with achalasia (n = 15 each, three subtypes), those with gastroesophageal reflux disease (GERD; n = 13), those with eosinophilic esophagitis (EoE; n = 8), and those with systemic sclerosis (SSc; n = 5). Luminal cross-sectional area (CSA) and pressure were measured by the FLIP catheter positioned across the EGJ. Work done on the EGJ (EGJW) was computed (millijoules, mJ) at 40-mL distension. Additionally, a separate method was developed to estimate the "work required" to fully open the EGJ (EGJROW) when it did not open during the procedure. EGJW for controls had a median [interquartile range (IQR)] value of 75 (56-141) mJ. All achalasia subtypes showed low EGJW compared with controls (P < 0.001). Subjects with GERD and EoE had EGJW 54.1 (6.9-96.3) and 65.9 (10.8-102.3) mJ, similar to controls (P < 0.08 and P < 0.4, respectively). The scleroderma group showed low values of EGJW, 12 mJ (P < 0.001). For patients with achalasia, EGJROW was the greatest and had a value of 210.4 (115.2-375.4) mJ. Disease groups with minimal or absent EGJ opening showed low values of EGJW. For patients with achalasia, EGJROW significantly exceeded EGJW values of all other groups, highlighting its unique pathophysiology. Balancing the relationship between EGJW and EGJROW is potentially useful for calibrating achalasia treatments and evaluating treatment response.NEW & NOTEWORTHY Changes in pressure and diameter occur at the EGJ during esophageal emptying. Similar changes can be observed during FLIP panometry. Data from healthy and diseased individuals were used to estimate the mechanical work done on the EGJ during distension-induced relaxation or, in instances of failed opening, work required to open the EGJ. Quantifying these parameters is potentially valuable to calibrate treatments and gauge treatment efficacy for subjects with disorders of EGJ function, especially achalasia.

[Update on Endoscopic Therapies for the Treatment of GERD: GERDX, MUSE, EsophyX]

Gastroesophageal reflux disease (GERD) has been a problem for patients throughout in recent decades worldwide and its prevalence is increasing. Until 20 years ago, the established treatments were the proton pump inhibitors (PPI) and varieties of laparoscopic fundoplication (LF). Increasing experience with endoscopy and knowledge of the oesophagogastric junction (EGJ) has led to new options in the treatment of GERD. However, promising short term effects have been found with radiofrequency ablation (RFA, Stretta device), endoscopic mucosal resection (ARMS) for induction of scar tissue at the lower oesophageal sphincter (LES) and endoscopic suture devices like GERDX, MUSE and EsophyX to reconstruct the flap valve at the EGJ. Long-term follow-up data and randomised controlled studies in comparison to LF are still rare.

ESNM/ANMS consensus paper: Diagnosis and management of refractory gastro-esophageal reflux disease

Up to 40% of patients with symptoms suspicious of gastroesophageal reflux disease (GERD) do not respond completely to proton pump inhibitor (PPI) therapy. The term "refractory GERD" has been used loosely in the literature. A distinction should be made between refractory symptoms (ie, symptoms may or may not be GERD-related), refractory GERD symptoms (ie, persisting symptoms in patients with proven GERD, regardless of relationship to ongoing reflux), and refractory GERD (ie, objective evidence of GERD despite adequate medical management). The present ESNM/ANMS consensus paper proposes use the term "refractory GERD symptoms" only in patients with persisting symptoms and previously proven GERD by either endoscopy or esophageal pH monitoring. Even in this context, symptoms may or may not be reflux related. Objective evaluation, including endoscopy and esophageal physiologic testing, is requisite to provide insights into mechanisms of symptom generation and evidence of true refractory GERD. Some patients may have true ongoing refractory acid or weakly acidic reflux despite PPIs, while others have no evidence of ongoing reflux, and yet others have functional esophageal disorders (overlapping with proven GERD confirmed off therapy). In this context, attention should also be paid to supragastric belching and rumination syndrome, which may be important contributors to refractory symptoms.

Mast cell effects on esophageal smooth muscle and their potential role in eosinophilic esophagitis and achalasia

Mast cells and eosinophils are the key effector cells of allergic disorders. Although most studies on eosinophilic esophagitis (EoE), an allergic disorder of the esophagus, have focused on the role of eosinophils, recent studies suggest a major role for mast cells in causing the clinical manifestations of this disease. Cellular and animal studies have demonstrated that mast cells can cause esophageal muscle cells to proliferate and differentiate into a more contractile phenotype, and that mediators released by degranulating mast cells such as tryptase and histamine can activate smooth muscle contraction pathways. Thus, activated mast cells in the esophageal muscularis propria might cause esophageal motility abnormalities, including the failure of lower esophageal sphincter relaxation typical of achalasia. In addition, mast cells have been implicated in the pathogenesis of a number of neurodegenerative disorders of the central nervous system such as Alzheimer's and Parkinson's diseases, because degranulating mast cells release proinflammatory and cytotoxic mediators capable of damaging neurons. Such mast cell degranulation in the myenteric plexus of the esophagus could cause the loss of enteric neurons that characterizes achalasia. In this report, we review the molecular mechanisms of esophageal smooth muscle contraction, and how mast cells products might affect that muscle and cause neurodegeneration in the esophagus. Based on these data, we present our novel, conceptual model for an allergy-induced form of achalasia mediated by mast cell activation in the esophageal muscularis propria.

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.

Effects of upper airway obstruction or hypoxia on gastroesophageal reflux in newborn lambs

BACKGROUND

Although it is commonly accepted that upper airway obstruction (UAO) increases gastroesophageal reflux (GER), the link is poorly understood and insufficiently documented. In addition, while hypoxia is often encountered in infants with UAO, its consequences on GER are virtually unknown. The two aims of the present study were to characterize the effects of (1) UAO and (2) hypoxia on GER.

METHODS

Seventeen lambs underwent polysomnographic and esophageal impedance/pH-metry monitoring during UAO vs. a control condition (6 h, ten lambs) or 10% hypoxia vs. normoxic condition (3 h, seven other lambs).

RESULTS

Moderate-to-severe UAO was maintained throughout monitoring (inspiratory tracheal pressure of -13 (-15, -12) cm H₂O vs. -1 (-1, -1) cm H₂O in control condition, p = 0.005). While the number of GERs increased with UAO (2 (1, 4) vs. 0 (0, 3) in the control condition, p = 0.03), the increase was less than anticipated and inconsistent among the lambs. Also, sustained 10% hypoxia did not alter the number of GERs (2 (1, 3) vs. 0 (0, 5) in the control condition, p = 0.9).

CONCLUSIONS

The presence of an UAO for 6 h mildly increased the number of GERs, whereas hypoxia for 3 h had no significant effect.

IMPACT

The effect of upper airway obstruction and hypoxia on gastroesophageal reflux is poorly documented in the neonatal period. A moderate-to-severe upper airway obstruction for 6 h results in a mild, inconsistent increase in the number of gastroesophageal refluxes. Overall, a hypoxia of 10% for 3 h had no significant impact on gastroesophageal reflux. The prescription of an antireflux medication in infants with upper airway obstruction must not be systematic but rely on objective signs of a pathologic gastroesophageal reflux.

High-resolution manometry features of paraesophageal hernia

BACKGROUND

Paraesophageal hernias (PEH) can be associated with obstructive symptoms, but high-resolution manometry (HRM) characteristics have not been described in detail.

METHODS

HRM studies of confirmed PEH patients (n = 60, 66.3 ± 1.5 years, 76.7% F), axial hernias (n = 125, 56.1 ± 1.1 years, 58.4% F), and healthy controls (n = 20, 27.9 ± 0.7 years, 45% F) were analyzed. Axial hernias (type 1) were compared to PEH subtyped as isolated PEH (type 2), PEH with axial hernia (type 3), PEH with herniated abdominal organs (type 4), and unknown. Distal contractile integral (DCI), esophageal length, lower esophageal sphincter pressures (LESP), EGJ contractile integral (EGJ-CI), and integrated relaxation pressure (IRP) were extracted. Intra-luminal pressures were measured proximal (intrabolus pressure, IBP) and distal (intragastric pressure, IGP) to EGJ. Univariate and multivariate analyses were performed to characterize esophageal and EGJ motor physiology in PEH.

KEY RESULTS

PEH patients had LESP and EGJ-CI similar to controls; axial hernia patients had lower LESP. While IRP was within normal limits, PEH had elevated IBP and IGP, and shorter esophageal length compared to axial hernia and normal controls (P ≤ .0001 across groups). Short esophageal length was consistent across PEH subtypes (P = .06). On multivariate regression analysis, IBP remained an independent predictor of PEH (P < .0001). Within PEH subtypes, gastric pressure was higher when axial HH was also present, in contrast to isolated PEH (P = .03); other metrics did not differ.

CONCLUSIONS & INFERENCES

Luminal pressure increase both upstream and downstream of the EGJ on HRM likely represents obstructive phenomena in PEH, identification of which may support suspicion of PEH.

Belching in Gastroesophageal Reflux Disease: Literature Review

Belching is a common phenomenon. However, it becomes bothersome if excessive. Impedance–pH monitoring can classify the belching into two types: gastric belching and supragastric belching (SGB). The former is a physiological mechanism to vent swallowed air from the stomach, whereas the latter is a behavioral disorder. Gastroesophageal reflux disease (GERD) is the most relevant condition in both types of belching. Recent findings have raised awareness that excessive SGB possibly sheds light on the pathogenesis of a part of proton pump inhibitor (PPI) refractoriness in GERD. SGB could cause typical reflux symptoms such as heartburn, regurgitation or chest pain in two ways: SGB-induced gastroesophageal reflux or SGB-induced esophageal distension. In PPI-refractory GERD, it is important to detect hidden SGB as a cause of reflux symptoms since SGB requires psychological treatment instead of high dose PPIs or pain modulators. In the case of PPI-refractory GERD with excessive SGB, recent studies imply that the combination of a psychological approach and conventional treatment can improve treatment outcome.

Three-Dimensional Pressure Profile of the Lower Esophageal Sphincter and Crural Diaphragm in Patients with Achalasia Esophagus

BACKGROUND & AIMS

Smooth muscles of the lower esophageal sphincter (LES) and skeletal muscle of the crural diaphragm (esophagus hiatus) provide the sphincter mechanisms at the esophagogastric junction (EGJ). We investigated differences in the 3-dimensional (3D) pressure profile of the LES and hiatal contraction between healthy subjects and patients with achalasia esophagus.

METHODS

We performed a prospective study of 10 healthy subjects (controls; 7 male; mean age, 60 ± 15 years; mean body mass index, 25 ± 2) and 12 patients with a diagnosis of achalasia (7 male; mean age, 63 ± 13 years; mean body mass index, 26 ± 1), enrolled at a gastroenterology clinic. Participants underwent 3D high-resolution manometry (3DHRM) with a catheter equipped with 96 transducers (for the EGJ pressure recording). A 0.5-mm metal ball was taped close to the transducer number 1 of the 3DHRM catheter. EGJ pressure was recorded at end-expiration (LES pressure) and at the peak of forced inspiration (hiatal contraction). Computed tomography (CT) scans were performed to localize the circumferential location of the metal ball on the catheter. Esophagus, LES, stomach, right and left crus of the diaphragm, and spine were segmented in each CT scan slice images to construct the 3D morphology of the region.

RESULTS

The metal ball was located at the 7 o'clock position in all controls. The circumferential orientation of metal ball was displaced 45 to 90 degrees in patients with achalasia compared with controls. The 3D-pressure profile of the EGJ at end-expiration and forced inspiration revealed marked differences between the groups. The LES turns to the left as it entered from the chest into the abdomen, forming an angle between the spine and LES. The spine-LES angle was smaller in patients with achalasia (104°) compared with controls (124°). Five of the 10 subjects with achalasia had physical breaks in the left crus of the diaphragm CONCLUSIONS: Besides LES, the 3D pressure profile of the EGJ can indicate anatomic and functional abnormalities of the crural diaphragm muscle in patients with achalasia esophagus. Further studies are needed to define the nature of hiatal and crural diaphragm dysfunction in patients with achalasia of the esophagus.

Gastroesophageal Reflux Disease in the Neonatal Intensive Care Unit Neonate: Controversies, Current Understanding, and Future Directions

Gastroesophageal reflux (GER) is considered physiologic and is a normal process; whereas, when aerodigestive consequences are associated, it is often interpreted as GER disease (GERD). However, the distinction between them remains a challenge in infants in the NICU. Reflux-type of symptoms are heterogeneous, and often managed with changes in diet, feeding methods, and acid-suppressive therapy; all these empiric therapies lack objectivity; hence, practice variation is universal. We clarify the current controversies, explain the potential role of GERD in causing symptoms and complications, and highlight current advances. The evidence basis for the diagnostic strategies is discussed.

Characteristics of a Subset of Achalasia With Normal Integrated Relaxation Pressure

Background/Aims

Integrated relaxation pressure (IRP) is a critical diagnostic criterion to define achalasia. However, there are some cases with typical symptoms and signs of achalasia but with normal IRP. The aim of this study is to evaluate the clinical characteristics of patients with achalasia with normal IRP and outcomes after peroral endoscopic myotomy (POEM).

Methods

Patients with achalasia were collected in whom POEM was performed from November 2014 to April 2018 at CHA Bundang Medical Center. Achalasia with normal IRP was defined by findings compatible to achalasia in Eckardt score, endoscopy with endoscopic ultrasound, high-resolution manometry, impedance planimetry (EndoFlip), and timed esophagogram.

Results

POEM was performed in 89 patients with achalasia; among them, 24 (27%) patients were diagnosed with achalasia with normal IRP. Patients with achalasia with normal IRP were older, had longer duration of symptom, and had a more tortuous esophagus. In EndoFlip, the distensibility index and cross-sectional area were higher in patients with normal IRP. Therapeutic outcomes showed no statistically significant differences. On correlation analysis, IRP had negative correlations with age, disease duration, and distensibility index.

Conclusions

Patients with achalasia of normal IRP value were older and had longer disease duration and higher distensibility index and cross-sectional area than patients with achalasia with abnormal relaxation of lower esophageal sphincter. Therapeutic outcomes were not different between the 2 groups.