Lower Esophageal Sphincter Relaxation Research Articles

Effects of Cholecystokinin on Esophageal Motor Response to Distension in Asymptomatic Volunteers.

Cholecystokinin (CCK) administration has been shown to reduce lower esophageal sphincter (LES) pressure in normal subjects in manometric studies. Functional luminal imaging probe (FLIP) panometry offers a method to assess esophageal motility in response to sustained distension though mechanisms related to this response remain unexplored. The aim of this study is to evaluate the effect of CCK-8 on the esophageal response to distension in asymptomatic volunteers using FLIP. Esophageal response to distension was studied in 7 asymptomatic volunteers (mean age ± SD [27 ± 2]; 86% female) before and after CCK-8 administration in a crossover study design. During sedated endoscopy, FLIP was performed twice with CCK-8 administered via intravenous push in one of 2 protocols: during filling (n = 4) or during emptying (n = 3). Esophagogastric junction distensibility index (EGJ-DI) at 60 mL fill volume and esophageal body contractile response patterns were analyzed. During the baseline FLIP study, all subjects had a contractile response with repetitive antegrade contractions both before and after CCK-8 administration. However, a sustained LES contraction or a sustained occluding contraction with esophageal shortening was observed in all subjects in the filling protocol, but in none during the emptying protocol. EGJ-DI was similar before and after CCK-8 during both filling (4.7 ± 1.9 mm2/mmHg vs 4.3 ± 1.8 mm2/mmHg) and emptying protocol (7.5 ± 1.4 mm2/mmHg vs 6.9 ± 0.6 mm2/mmHg). While EGJ-DI appeared unaffected by CCK-8 administration in asymptomatic volunteers, CCK induced spastic-reactive contractions of the LES during distention suggesting that exogenous CCK interferes with normal LES relaxation during secondary peristalsis.

Malaysian joint societies' consensus recommendations on diagnosis and management of disorders of esophagogastric junction outflow.

Disorders of esophagogastric junction (EGJ) outflow, including achalasia and EGJ outflow obstruction, are motility disorders characterized by inadequate relaxation of lower esophageal sphincter with or without impaired esophageal peristalsis. Current guidelines are technical and less practical in the Asia-Pacific region, and there are still massive challenges in timely diagnosis and managing these disorders effectively. Therefore, a Malaysian joint societies' task force has developed a consensus on disorders of EGJ outflow based on the latest evidence, while taking into consideration the practical relevance of local and regional context and resources. Twenty-one statements were established after a series of meetings and extensive review of literatures. The Delphi method was used in the consensus voting process. This consensus focuses on the definition, diagnostic investigations, the aims of treatment outcome, non-surgical or surgical treatment options, management of treatment failure or relapse, and the management of complications. This consensus advocates the use of high-resolution esophageal manometry for diagnosis of disorders of EGJ outflow. Myotomy, via either endoscopy or laparoscopy, is the preferred treatment option, while pneumatic dilatation can serve as a secondary option. Evaluation and management of complications including post-procedural reflux and cancer surveillance are recommended.

Altered Esophageal Smooth Muscle Phenotype in Achalasia.

Achalasia is a disorder characterized by impairment in lower esophageal sphincter relaxation and esophageal aperistalsis, caused primarily by loss of inhibitory innervation. However, little is known about associated changes in esophageal smooth muscle. We examined the contractile phenotype and innervation of the circular smooth muscle, as well as inflammatory status, and correlated these with patient-specific parameters. Circular smooth muscle biopsies were obtained in consecutive patients with achalasia undergoing peroral endoscopic myotomy. Axonal innervation and neurotransmitter subtypes were determined with immunocytochemistry, and this was used with quantitative Polymerase Chain Reaction (qPCR) to characterize smooth muscle proliferation and cellular phenotype, as well as collagen expression. These were compared to control tissue obtained at esophagectomy and correlated with patient demographic factors including age, onset of symptoms, and Eckhardt score. Biopsies of smooth muscle were obtained from 25 patients with achalasia. Overall, there was increased mast cell number and collagen deposition but increased smooth muscle cell proliferation vs control. There was a striking drop in axon density over controls, with no differences among subtypes of achalasia. Immunocytochemical analysis showed increased expression of the contractile marker α-smooth muscle actin, principally in Type 1 achalasia, that increased with disease duration, while qPCR identified increased mRNA for smoothelin with decreased myosin heavy chain and collagen 3a1, but not collagen 1a1. The thickened circular smooth muscle layer in achalasia is largely denervated, with an altered contractile phenotype and fibrosis. Biopsies obtained during peroral endoscopic myotomy provide a means to further study the pathophysiology of achalasia.

Correlation between Lower Esophageal Sphincter Metrics on High-Resolution Manometry and the Clinical Presentation of Patients with Newly Diagnosed Achalasia

Achalasia is characterized by aperistalsis with poor relaxation of the lower esophageal sphincter (LES). We aimed to systematically assess whether LES metrics on high-resolution manometry (HRM) correlate with the symptomatic or endoscopic presentation of patients with achalasia. A retrospective study was performed at two tertiary medical centers. All cases of newly diagnosed, untreated achalasia were reviewed for demographics, symptoms, and endoscopic findings. These were correlated with HRM metrics, including LES basal pressure (LESP), integrated relaxation pressure (IRP), percent LES relaxation, and esophagogastric junction (EGJ) morphology. 108 achalasia patients were included; 56 (51.9%) were men, with a mean overall age of 55.6 ± 17.9 years old. Achalasia subtypes included 23.1% with Type I, 65.7% Type II, and 11.1% Type III. Mean LESP was 40.9 ± 13.7 mmHg, IRP 26.8 ± 11.5 mmHg, with 36% ± 20% LES relaxation. On univariate analyses, a higher IRP was associated with age < 50 (p = 0.028), female sex (p = 0.030), Arab ethnicity (p < 0.001), weight loss (p = 0.016), a tortuous esophagus (p = 0.036), and resistance at the EGJ (p = 0.033). However, on multivariate regression analyses, only ethnicity remained significantly associated with IRP. No unique variables were associated with either LESP or percent LES relaxation. Achalasia subtype and Eckardt score were not associated with any LES metrics. Non-Type 1 EGJ morphology was associated with a lower LESP. LES metrics on HRM do not appear to correlate with the clinical or endoscopic presentation of patients with untreated achalasia.

Esophageal motility disorders in symptomatic patients and its relation to age

BackgroundAlthough swallowing disorders can impact individuals of any age, some are unique to the elderly, and others are frequent. Some disorders, such as achalasia, are diagnosed by esophageal manometry studies, which assess lower esophageal sphincter (LES) pressure and relaxation, peristalsis in the esophageal body, and contraction wave characteristics. This research aimed to evaluate esophageal motility dysfunction in symptomatic patients and its relation to age.MethodsConventional esophageal manometry was performed on 385 symptomatic patients who were divided into two groups; Group A (age < 65 years old) and Group B (age ≥ 65 years). The geriatric assessment for Group B included cognitive, functional, and clinical frailty scales (CFS). Additionally, a nutritional assessment was done for all patients.ResultsAbout one-third of the patients (33%) had achalasia, in which manometric results were significantly higher in Group B (43.4%) than in Group A (28.7%) (P = 0.016).The resting lower esophageal sphincter (LES) pressure, as determined by manometry examination, was significantly lower in Group A than in Group B. In contrast, complete LES relaxation percentage and normal esophageal body peristalsis were significantly higher in Group A than in Group B. Patients who exhibited evidence of achalasia in the manometric study had a significantly increased risk of established malnutrition and functional impairment.ConclusionsAchalasia is a prevalent cause of dysphagia in elderly patients, placing them at risk of malnutrition and functional impairment. Thus, a multidisciplinary approach is vital when providing care for this population.

S484 Characterizing Lower Esophageal Sphincter Dysfunction, Integrated Relaxation Pressure vs Distensibility Index: Who Gives a Flip?

Introduction: Characterizing lower esophageal sphincter dysfunction is of paramount importance when classifying disorders of esophageal motility. Integrated relaxation pressure (IRP) during high resolution impedance manometry (HRIM) has traditionally been used but has been found to be imperfect. Functional lumen impedance planimetry (FLIP) has been developed to be complementary with HRIM for discerning esophageal motility disorders. The aim of this study is to evaluate the relationship between distensibility index (DI) and IRP pertaining to LES relaxation made with FLIP compared with HRIM. Methods: A retrospective review of 227 patients was performed. Patients were classified as having normal IRP (less than 15 mmHg) or abnormal IRP (greater than or equal to 15 mmHg) as measured by HRIM. The average distensibility index as measured by FLIP for patients in both groups was compared. The patient groups were then subdivided into four groups on the basis of normal or abnormal DI using each of the common standards for abnormality (less than or equal to 2.8 mm2/mmHg and less than or equal to 2.0 mm2/mmHg). Fisher’s exact analysis was completed to determine whether abnormal IRP and abnormal DI are related. Results: In patients with a normal IRP (< 15) as measured by HRIM, the mean DI was 4.02 with a standard deviation of 2.89. In patients with abnormal IRP ( ≥ 15), the mean DI was 3.03 with a standard deviation of 2.58. The difference in the mean DIs was statistically significant (p-value = 0.0234, t-test) . Table illustrates the number of patients in each IRP and DI subgroup using both cutoff standards. There was no statistically significant difference in the observed patient frequencies of any classification than would be expected by chance. Conclusion: We found that a normal IRP (< 15mmHg) is associated with higher DIs and that an abnormal IRP (≥15 mmHg) was associated with a DI ≤ 3.1. However, abnormal DI by the standards of either cutoff was not related to having abnormal IRP. Our data supports that both a high IRP and reduced DI suggest impaired LES relaxation, but a DI of less than 2.0 and 2.8 does not predict an IRP of less than 15 mmHg, suggesting some variability between the two metrics. While the chi-squared analysis approached but did not achieve statistical significance in this study, repetition with larger sample sizes in the future may yield a clearer relationship between abnormal IRP and abnormal DI. Table 1. - Fisher's Exact Test of Number of Patients Classified By Distensbility Index (DI) and Integrated Relaxation Pressure Normality and Abnormality DI < 2.8 mm2/mmHg DI ≥ 2.8 mm2/mmHg DI < 2.0 mm2/mmHg DI ≥ 2.0 mm2/mmHg IRP< 15 mmHg 16 32 11 37 IRP ≥15 mmHg 81 83 63 101 p = 0.07 p = 0.06

EndoFLIP Topography: Motor Patterns in an Obstructed Esophagus

EndoFLIP Topography: Motor Patterns in an Obstructed Esophagus

Relationship between dysphagia, lower esophageal sphincter relaxation, and esophagogastric junction distensibility.

It is debated whether high-resolution manometric (HRM) integrated relaxation pressure (IRP) or functional lumen imaging probe (FLIP) distensibility index (DI) is the superior measure of esophagogastric junction (EGJ) opening. We examined the relationship between the DI and IRP and assessed correlations with dysphagia symptoms in patients with achalasia and EGJ outflow obstruction (EGJOO). Patients with achalasia and those with barium tablet retention at the EGJ were grouped as follows: Group 1:Achalasia (IRP≥15mmHg+complete absence of normal peristalsis); Group 2: Manometric+FLIP EGJOO (IRP≥15mmHg with some intact peristalsis+DI≤2.8mm2 /mmHg); Group 3: Abnormal DI only (DI≤2.8mm2 /mmHg+IRP <15mmHg); and Group 4: Normal IRP and DI (IRP≥15mmHg+DI>2.8mm2 /mmHg). Correlation between the DI, baseline lower esophageal sphincter pressure (BLESP), IRP, and dysphagia (Eckardt score) was assessed. Multivariable analysis was used to assess variables associated with dysphagia score ≥2. A total of 79 patients were included: Group 1 (n=31), Group 2 (n=33), Group 3 (n=14), and Group 4 (n=1). DI did not correlate with BLESP or IRP in the whole sample or subgroups. DI was the only variable associated with dysphagia score ≥2 (p=0.006). DI<1.25mm2 /mmHg had sensitivity of 87% and specificity of 52% (p=0.0003) for dysphagia score ≥2. DI does not correlate with HRM EGJ measurements and is the metric with the strongest effect on dysphagia severity. The various biological elements that may cause restrictive EGJ function should be the subject of future studies.

The Outcomes of Performing Partial Fundoplication Based on Endoflip Versus Manometric Findings.

The surgical management of gastroesophageal reflux disease (GERD) involves extensive diagnostic studies and sophisticated surgical techniques. The workup should be comprehensive and purposeful. High resolution impedance manometry (HRIM) provides valuable information regarding peristalsis and lower esophageal sphincter relaxation. The disadvantages of HRIM such as intolerance or inability to pass the catheter led to its selective use or even omission especially in laparoscopic hiatal hernia repair with partial fundoplication. This pragmatic approach risks missing motility disorders in patients with secondary reflux symptoms related to achalasia or scleroderma. Endolumenal functional lumen imaging probe (endoFLIP) can fill this void as it evaluates the dynamics of the esophagogastric junction under sedation. This study aims to compare the outcomes of preoperative use of HRIM vs endoFLIP for laparoscopic repair of hiatal hernia with partial fundoplication. This is a retrospective cohort study for consecutive patients who underwent antireflux surgery with partial fundoplication between July 2018 and February 2021. Preoperative and postoperative outcomes were compared between two cohorts of patients: those with preoperative HRIM and those with preoperative endoFLIP. A total of 72 patients were evaluated, 41 had preoperative HRIM and 31 had endoFLIP. There was no statistically significant difference in their age, sex, BMI, duration of GERD symptoms, or proton pump inhibitors use. The endoscopic findings of esophagitis, hiatal hernia, and Hill's grade were comparable. There was no difference in the American Society of Anesthesiology classification or the choice of antireflux surgery. The improvement of postoperative GERD scores and dysphagia subscore was similar between the two groups. Performing partial fundoplication based on endoFLIP evaluation of the dynamics of the esophagogastric junction is safe and does not increase postoperative dysphagia compared to preoperative manometric use. Randomized prospective studies are needed to confirm the findings of this study.

Современные представления об этиопатогенезе и лечении ахалазии

Achalasia is a chronic neuromuscular disorder of esophagus with supposed autoimmunity, genetic disturbancies and viral infection. The disease is characterized by poor relaxation of lower esophageal sphincter and absent of body peristalsis. The inflammation, eosinophilic and lymphocytic infiltration may play role in loss of inhibitory ganglion in the myenteric plexus. High resolution manometry is a gold standard for diagnosis of achalasia, because it distinguish three types of disorder. The aim of treatment of achalasia is to reduce symptoms, such as dysphagia. The most effective modality of surgical treatment are Heller myotomy and peroral endoscopy myotomy. The pneumodilation is less preferable because of short-term effect and high rate of relapse. The relapse after surgical treatment can be present and correlates increase with the time after intervention

S3379 Comparing Common Anti-Reflux Surgeries to Their Outcomes and Complications

Introduction: Gastroesophageal reflux disease (GERD) is caused by frequent relaxation of lower esophageal sphincter for multiple reasons. Laparoscopic anti-reflux surgery is an alternative treatment for patients with refractory gastro-esophageal reflux disease. Our aim is to describe the outcomes of the four more common types of anti-reflux surgeries and their associated complications in patients with a long-standing history of GERD. Methods: A retrospective review of 278 patients undergoing four different anti-reflux surgeries at a tertiary care center for esophageal reflux excellence was performed between 2015 and 2020. Primary outcomes included identifying all-cause readmission rates at 30 and 90-days, length of stay, whether they were put on anti-reflux medications postoperatively and whether they needed a secondary surgery for revisions. Secondary outcomes included analyzing postoperative complications such as bleeding requiring transfusions, infections such as urinary tract infections (UTI), pneumonias or central line associated blood stream infections (CLABSI) as well as post-operative cardiac arrythmias. Analysis included age, gender, body mass index, surgery duration, and perioperative data. STATA 14.2 was used for appropriate statistical analysis. Descriptive analysis as well as a simple and multiple regression analysis were used. Results: The laparoscopic repair of paraoesophageal hernia was the most commonly performed procedure 137/278 (49.3%), followed by laparoscopic repair of hiatal hernia in 98/278 (35.3%), the Nissen Fundoplication procedure in 31/278 (11.2%) and Redo Nissen fundoplication in 12/278 (4.3%). The average length of stay was 4.8 days (95% CI 4.5-5.2). Women were the majority of patients 207/278 (75%) and the average age was 65-year-old (95% confidence interval: 64-67). Obesity defined as BMI >30 was present in 42.9% of patients with a (95% confidence interval: 0.37-0.48). Only 12% of the patients required surgical revision (95% confidence interval: 0.09-0.17). Complications including need for surgical revision, readmission, infection, bleeding or arrythmia occurred in 73 patients (26%) of the patients. Conclusion: There was a low risk for peri-operative complications, readmission and need for repeat surgery. Different procedures were effective in treating GERD with laparoscopic repair of hiatal hernia having significantly more need for post-operative medications to treat GERD. The data includes significantly more women which could limit the generalizability to men.

Involvement of interstitial cells of Cajal in nicotinic acetylcholine receptor-induced relaxation of the porcine lower esophageal sphincter

The interstitial cells of Cajal (ICCs) play an important role in coordinated gastrointestinal motility. The present study aimed to elucidate whether or how ICCs are involved in the lower esophageal sphincter (LES) relaxation induced by stimulation of the nicotinic acetylcholine receptor. The application of 1,1-dimethyl-4-phenyl-piperazinium (DMPP; a nicotinic acetylcholine receptor agonist) induced a transient relaxation in the circular smooth muscle of the porcine LES. DMPP-induced relaxation was abolished by not only 1 μM tetrodotoxin but also the inhibition of ICC activity by pretreatment with 100 μM carbenoxolone (a gap junction inhibitor), pretreatment with 100 μM CaCCinh-A01 (an anoctamin-1 blocker acting as a calcium-activated chloride channel inhibitor), and pretreatment with Cl−-free solution. However, pretreatment with 100 μM Nω-nitro-L-arginine methyl ester had little effect on DMPP-induced relaxation. Furthermore, DMPP-induced relaxation was inhibited by pretreatment with 1 mM suramin, a purinergic P2 receptor antagonist, but not by 1 μM VIP (6–28), a vasoactive intestinal peptide (VIP) receptor antagonist. Stimulation of the purinergic P2 receptor with adenosine triphosphate (ATP) induced relaxation, which was abolished by the inhibition of ICC activity by pretreatment with CaCCinh-A01. In conclusion, membrane hyperpolarization of the ICCs via the activation of anoctamin-1 plays a central role in DMPP-induced relaxation. ATP may be a neurotransmitter for inhibitory enteric neurons, which stimulate the ICCs. The ICCs act as the interface of neurotransmission of nicotinic acetylcholine receptor in order to induce LES relaxation.

The Impact of Bariatric Procedures on Esophageal Motility

Bariatric operations may cause or cure gastroesophageal reflux disease (GERD). The comprehension of esophageal motility following different types of bariatric procedures may help understand the relationship between GERD and bariatric surgery. This review focused on the impact of bariatric procedures on esophageal motility. We found that lower esophageal sphincter resting pressure is increased after adjustable gastric banding; is unaltered or decreased after Roux-en-Y gastric bypass; and is decreased after sleeve gastrectomy. Lower esophageal sphincter relaxation may be abnormal after all these procedures. Esophageal body contractility is worsened after sleeve gastrectomy.

Ineffective Esophageal Motility: Need for Improvement in Diagnostic Criteria

Ineffective esophageal motility (IEM) is a hypomotility disorder with decreased contraction vigor and normally relaxing lower esophageal sphincter. Although IEM has been associated with poor esophageal clearance and gastroesophageal reflux, it is also seen in asymptomatic subjects and is often of unclear clinical significance. The Chicago classification version 4.0 updated the diagnostic threshold to require &gt;70% weak or fragmented swallows or ≥50% failed swallows for a conclusive diagnosis of IEM. Provocation testing are recommended in borderline cases to assess clinical relevance. Prospective trials are needed to further refine the diagnostic criteria, understand the pathophysiology, and develop an effective treatment for IEM.

Effects of codeine on esophageal peristalsis in humans using high resolution manometry.

Opioid receptors agonists have been demonstrated to impair lower esophageal sphincter (LES) relaxation and induce spastic esophageal dysmotility, but little was known for their impact on distension-induced secondary peristalsis. The aim of the study was to investigate the hypothesis whether acute administration of codeine can influence physiological characteristics of primary and secondary peristalsis in healthy adults. Eighteen healthy volunteers (13 men, mean age 27.5years, aged 20-43years) underwent high resolution manometry (HRM) with a catheter containing an injection port in mid-esophagus. Secondary peristalsis was performed with 10 and 20mL rapid air injections. Two different sessions including acute administration of codeine (60mg) or the placebo were randomly performed. Codeine significantly increased 4-s integrated relaxation pressure (IRP-4s) (P=0.003) and shortened distal latency (DL) (P=0.003) of primary peristalsis. The IRP-4s of secondary peristalsis was also significantly higher after codeine than the placebo during air injections with 10mL (P=0.048) and 20mL (P=0.047). Codeine significantly increased the frequency of secondary peristalsis during air injections with 10mL than the placebo (P=0.007), but not for air injection with 20mL (P=0.305). In addition to impair LES relaxation and reduce distal latency of primary peristalsis, codeine impairs LES relaxation of secondary peristalsis and increases secondary peristaltic frequency. Our study supports the notion in human esophagus that the impact of opioids on peristaltic physiology appears to be present in both primary and secondary peristalsis.

The Reflux Symptoms Before and After Peroral Endoscopic Myotomy of Chinese Patients With Achalasia.

Background/AimsAchalasia is a rare disease, but the incidence is increasing recently. Peroral esophageal myotomy (POEM) is an effective treatment. Regurgitation is a common symptom before and after POEM. Our aim is to investigate the factors related to preoperative and postoperative reflux symptoms.MethodsOur study was retrospective. The achalasia patients diagnosed by high-resolution manometry and gastroscopy were divided into reflux group and non-reflux group before and after POEM, respectively. General information, symptoms, POEM information, and manometric results were compared.Results(1) Ninety-six of 130 patients had reflux symptoms before POEM. The lower esophageal sphincter pressure (LESP) in the reflux group was significantly higher than the non-reflux group (P = 0.023), while integrated relaxation pressure (IRP) was similar. The reflux group had longer esophagus than the non-reflux group (P = 0.006). Reflux symptoms were not related to subtypes of achalasia. (2) Twenty-five of 84 patients had reflux symptoms after POEM. Postoperative Eckardt scores, LESP, and 4-second IRP (4sIRP) were significantly lower than the preoperative values (P < 0.001). The preoperative values and POEM information were similar between the postoperative 2 groups and there was no significant difference in the presence of preoperative reflux symptoms between 2 groups. The postoperative LESP and 4sIRP were similar between the 2 groups, however, the postoperative UESP was significantly higher in the reflux group than the non-reflux group (P = 0.042). The non-reflux group had more declines in Eckardt scores and LESP than the reflux group.ConclusionsThe reflux symptoms of achalasia patients without treatment were mainly due to food retention. The postoperative reflux symptoms were not the sign of the excessive relaxation of lower esophageal sphincter.

Optional Management of Achalasia in 2021: Dilatation or Myotomy

AbstractAchalasia cardia is a primary motility disorder of the esophagus, defined by lack of normal esophageal peristalsis along with inadequate relaxation of lower esophageal sphincter . The mainstay of management in achalasia includes pneumatic dilatation, Heller’s myotomy and peroral endoscopic myotomy (POEM). Pneumatic dilatation and Heller’s myotomy have gained maturity over several decades. The current best practice with regard to pneumatic dilatation is graded and on-demand dilatation in appropriately selected cases with type I and II achalasia. Laparoscopic Heller’s myotomy plus partial fundoplication is minimally invasive with reduced postoperative reflux and has virtually replaced open Heller’s myotomy with or without fundoplication. The subtyping of achalasia using high-resolution manometry bears prognostic significance and may help in choosing appropriate therapeutic modality in these patients. Since all the three modalities are effective for type I and II achalasia, the choice among these depends on the availability, expertise, and patient’s preferences. On the other hand, POEM is more effective than pneumatic dilatation and Heller’s myotomy and, therefore, preferred in type III achalasia. Although POEM is effective across the spectrum of esophageal motility disorders, the incidence of gastroesophageal reflux is high and needs to be considered while choosing among various options in these patients. In cases with failed POEM, redo POEM appears to be effective in alleviating symptoms.

Manometric changes of the esophagus in morbidly obese patients.

This prospective study aimed to determine the manometric pattern and the prevalence of esophageal dysmotility in 79 morbidly obese patients selected for laparoscopic sleeve gastrectomy. After clinical evaluation and upper gastrointestinal endoscopy, high-resolution esophageal manometry was performed. The esophageal peristalsis, lower esophageal sphincter (LES) basal pressure, and LES relaxation were evaluated. Demographic data showed a predominance of females (55.70%) and both females and males were in the 5th decade of life. In addition, approximately 3/4 of the patients (78.48%) were from the urban zone. The mean body mass index of the patients was 46.40±6.0069 kg/m2, with a maximum of 61 kg/m2. The LES basal pressure was normal in 59.49% of the patients, with a mean value of 31.40±18.43 mmHg. LES basal hypertonia was observed in 26.58%, and LES hypotonia in 13.93% of patients; 46.84% (37 patients) had abnormal manometric findings: 24.05% (19 patients) had EGJ outflow obstruction, 12.66% (10 patients) ineffective esophageal motility, 3.8% (3 patients) distal esophageal spasm, 3.8% (3 patients) Jackhammer esophagus, 2 cases were suggestive for type 2 achalasia but in asymptomatic patients. Ineffective esophageal motility was not associated with diabetes mellitus type 2 or erosive esophagitis according to our data. Hiatal hernia (HH) was manometrically diagnosed in 23 patients (29.11%). Preoperative high-resolution esophageal manometry in obese patients demonstrated a high prevalence of motility disorders, but in asymptomatic patients, thus in the future, we require more studies and larger cohorts to better appreciate the clinical impact.

Physiological and pathological roles of the accommodation response in lower esophageal sphincter relaxation during wet swallows

The preparatory accommodation response of lower esophageal sphincter (LES) before swallowing is one of the mechanisms involved in LES relaxation during wet swallows, however, the physiological and/or pathological roles of LES accommodation remain to be determined in humans. To address this problem, we conducted a prospective observational study of 38 patients with normal high-resolution manometry (HRM) and 23 patients with idiopathic esophagogastric junction outflow obstruction (EGJOO) to assess dry and wet swallows. The LES accommodation measurement was proposed for practical use in evaluating the LES accommodation response. Although swallow-induced LES relaxation was observed in both dry and wet swallows, LES accommodation (6.4, 3.1–11.1 mmHg) was only observed in wet swallows. The extent of LES accommodation was impaired in idiopathic EGJOO (0.6, − 0.6–6 mmHg), and the LES accommodation measurement of patients with idiopathic EGJOO (36.8, 29.5–44.3 mmHg) was significantly higher in comparison to those with normal HRM (23.8, 18–28.6 mmHg). Successful LES relaxation in wet swallowing can be achieved by LES accommodation in combination with swallow-induced LES relaxation. Impaired LES accommodation is characteristic of idiopathic EGJOO. In addition to the IRP value, the LES accommodation measurement may be useful for evaluating the LES relaxation function in clinical practice.

Role of transient receptor potential vanilloid subtype 2 in lower oesophageal sphincter in rat acid reflux oesophagitis

Gastroesophageal reflux disease (GERD) is a common gastrointestinal disorder. In the present study, we investigated TRP vanilloid subfamily member 2 (TRPV2) expression in lower oesophageal sphincter (LES) and its involvement in acid reflux oesophagitis in rats. Expression of TRPV2 and nerve growth factor mRNAs was significantly enhanced in LES of rats with reflux oesophagitis compared with normal rats. TRPV2 was mainly expressed in inhibitory motor neurons, and partly in intrinsic and extrinsic primary afferent neurons, and macrophages in LES of normal and reflux oesophagitis rats. Number of TRPV2-immunopositive nerve fibres was significantly increased, but that of nNOS-, CGRP-, and PGP9.5-nerve fibres was not changed in reflux oesophagitis compared with normal group. Probenecid produced nitric oxide production and relaxation in LES and this response was significantly enhanced in oesophagitis compared with normal group. Probenecid-induced relaxant effect was blocked by a TRPV2 inhibitor, tranilast, and a NOS inhibitor, NG-nitro-l-arginine methyl ester, in reflux oesophagitis rats. Oral administration of tranilast significantly improved body weight loss, oesophageal lesions, and epithelial thickness in oesophagitis model. These results suggest that up-regulation of TRPV2 in inhibitory motor neurons is involved in LES relaxation in oesophagitis model. TRPV2 inhibition might be beneficial for treatment of GERD.