Improving the Diagnostic Yield of High-Resolution Esophageal Manometry for GERD: The "Straight Leg-Raise" International Study.

BACKGROUND & AIMS: The straight leg raise (SLR) maneuver during high-resolution manometry (HRM) can assess esophagogastric junction (EGJ) barrier function by measuring changes in intraesophageal pressure (IEP) when intra-abdominal pressure is increased. We aimed to determine whether increased esophageal pressure during SLR predicts pathologic esophageal acid exposure time (AET). METHODS: Adult patients with persistent gastroesophageal reflux disease (GERD) symptoms undergoing HRM and pH-impedance or wireless pH study off proton pump inhibitor were prospectively studied between July 2021 and March 2022. After the HRM Chicago 4.0 protocol, patients were requested to elevate 1 leg at 45º for 5 seconds while supine. The SLR maneuver was considered effective when intra-abdominal pressure increased by 50%. IEPs were recorded 5 cm above the lower esophageal sphincter at baseline and during SLR. GERD was defined as AET greater than 6%. RESULTS: The SLR was effective in 295 patients (81%), 115 (39%) of whom had an AET greater than 6%. Hiatal hernia (EGJ type 2 or 3) was seen in 135 (46%) patients. Compared with patients with an AET less than 6%, peak IEP during SLR was significantly higher in the GERD group (29.7 vs 13.9 mm Hg; P < .001). Using receiver operating characteristic analysis, an increase of 11 mm Hg of peak IEP from baseline during SLR was the optimal cut-off value to predict an AET greater than 6% (area under the receiver operating characteristic curve, 0.84; sensitivity, 79%; and specificity, 85%), regardless of the presence of hiatal hernia. On multivariable analysis, an IEP pressure increase during the SLR maneuver, EGJ contractile integral, EGJ subtype 2, and EGJ subtype 3, were found to be significant predictors of AET greater than 6% CONCLUSIONS: The SLR maneuver can predict abnormal an AET, thereby increasing the diagnostic value of HRM when GERD is suspected. CLINICALTRIALS: gov ID: NCT04813029.

Effect of Increased Intra-abdominal Pressure on the Esophagogastric Junction: A Systematic Review.

With the advent of high-resolution esophageal manometry, it is recognized that the antireflux barrier receives a contribution from both the lower esophageal sphincter (intrinsic sphincter) and the muscle of the crural diaphragm (extrinsic sphincter). Further, an increased intra-abdominal pressure is a major force responsible for an adaptive response of a competent sphincter or the disruption of the esophagogastric junction resulting in gastroesophageal reflux, especially in the presence of a hiatal hernia. This review describes how the pressure dynamics in the lower esophageal sphincter were discovered and measured over time and how this has influenced the development of antireflux surgery.

High-Pressure Tactics: Jackhammer Esophagus-Diagnosing Is Easier than Treating.

Diagnosis of esophageal disorders is well ahead of available treatment options. With HRM, for example, one can identify numerous conditions and their variants, which may lose meaning if the clinical and therapeutic implications of these subclassifications are limited. We report an exemplary case of a patient with hiatal hernia complaining of reflux, dysphagia, and chest pain refractory to medical treatment. Jackhammer esophagus was diagnosed and a hybrid approach consisting of POEM and concomitant crural repair and Dor fundoplication is proposed.

Esophageal Lipoma and Liposarcoma: A Systematic Review.

BACKGROUND: Esophageal lipomatous tumors, also reported as fibrovascular polyp, fibrolipoma, angiolipoma, and liposarcoma, account for less than 1% of all benign mesenchymal submucosal tumors of the esophagus. Clinical presentation and therapy may differ based on location, size, and morphology. A comprehensive and updated systematic review of the literature is lacking. METHODS: A systematic review of the literature was performed according to PRISMA guidelines. Pubmed, Embase, Cochrane, and Medline databases were consulted using MESH keywords. Non-English written articles and abstracts were excluded. Sex, age, symptoms at presentation, diagnosis, tumor location and size, surgical approach and technique of excision, pathology, and morphology were extracted and recorded in an electronic database. RESULTS: Sixty-seven studies for a total of 239 patients with esophageal lipoma or liposarcoma were included in the qualitative analysis. Among 176 patients with benign lipoma, the median age was 55. The main symptoms were dysphagia (64.2%), transoral polyp regurgitation (32.4%), and globus sensation (22.7%). The majority of lipomas (85.7%) were intraluminal polyps, with a stalk originating from the upper esophagus. Overall, 165 patients underwent excision of the mass through open surgery (65.5%), endoscopy (27.9%), or laparoscopy/thoracoscopy (3.6%). Only 5 (3%) of patients required esophagectomy. Of the 11 untreated patients with an intraluminal polyp, 7 died from asphyxia. Overall, liposarcoma was diagnosed in 63 patients, and 12 (19%) underwent esophagectomy. CONCLUSION: Esophageal lipomatous tumors are rare but potentially lethal when are intraluminal and originate from the cervical esophagus. Modern radiological imaging has improved diagnostic accuracy. Minimally invasive transoral and laparoscopic/thoracoscopic techniques represent the therapeutic approach of choice.

Endoscopic stapling versus laser for Zenker diverticulum: a retrospective cohort study.

PURPOSE: Despite the evolution of the endoscopic techniques for the treatment of symptomatic Zenker diverticulum, comparative studies are lacking. Aim of this observational study was to compare safety, efficacy, and outcomes of endoscopic stapling (ES) versus Laser (EL). METHODS: A prospectively collected database of patients who underwent treatment for Zenker diverticulum at a single institution was reviewed. Consecutive patients treated by ES or EL were included in the study. Demographic data, presenting symptoms, diverticulum characteristics, and intra- and postoperative data were analyzed. The Functional Outcome Swallowing Scale (FOSS) and MD Anderson Dysphagia Inventory (MDADI) questionnaires were administered to assess severity of dysphagia and quality of life before and after treatment. RESULTS: Between March 2017 and September 2018, 36 patients underwent ES or EL. In the TL group (n = 19), the diverticulum size was smaller compared to the EL group (n = 17) (p = 0.002). Two perforations occurred in the EL group, one treated conservatively and the other requiring drainage of a mediastinal abscess. At a median follow-up of 16 months, symptoms improved in both groups but the number of patients with a postoperative FOSS score ≥ 2 significantly decreased only after EL (p < 0.001). The scores of all items of the MDADI questionnaire significantly increased in both groups, but the average delta values were greater in the EL patients (p < 0.001). CONCLUSIONS: Both TL and ES are effective treatment options for Zenker diverticulum. Postoperative quality of life was significantly higher in patients undergoing EL compared to ES.

Transthyretin at Admission and Over Time as a Marker for Clinical Outcomes in Critically Ill Trauma Patients: A Prospective Single-Center Study.

BACKGROUND: Transthyretin (TTR) has been described as a predictor for outcomes in medical and surgical patients. However, the association of TTR on admission and over time on outcomes has not yet been prospectively assessed in trauma patients. METHODS: This is a prospective observational study including trauma patients admitted to the intensive care unit (ICU) of a large Level I trauma center 05/2014-05/2015. TTR levels at ICU admission and all subsequent values over time were recorded. Patients were observed for 28 days or until hospital discharge. The association of outcomes and TTR levels at admission and over time was assessed using multivariable regression and generalized estimating equation (GEE) analysis, respectively. RESULTS: A total of 237 patients with TTR obtained at admission were included, 69 of whom had repeated TTR measurements. Median age was 40.0 years and median ISS 16.0; 83.1% were male. Below-normal TTR levels at admission (41.8%) were independently associated with higher in-hospital mortality (p = 0.042), more infectious complications (p = 0.032), longer total hospital length of stay (LOS) (p = 0.013), and ICU LOS (p = 0.041). Higher TTR levels over time were independently associated with lower in-hospital mortality (p = 0.015), fewer infections complications (p = 0.028), shorter total hospital and ICU LOS (both p < 0.001), and fewer ventilator days (0.004). CONCLUSIONS: In critically ill trauma patients, below-normal TTR levels at admission were independently associated with worse outcomes and higher TTR levels over time with better outcomes, including lower in-hospital mortality, less infectious complications, shorter total hospital and ICU LOS, and fewer ventilator days. Based on these results, TTR may be considered as a prognostic marker in this patient population.

Impact of Laparoscopic Repair of Large Hiatus Hernia on Quality of Life: Observational Cohort Study.

BACKGROUND: Laparoscopic surgery has proven safe and effective in the treatment of large hiatus hernia. Differences may exist between objectively assessed surgical outcomes, symptomatic scores, and patient-reported outcomes. METHODS: An observational, single-arm cohort study was conducted in patients undergoing primary laparoscopic repair with crura mesh augmentation and Toupet fundoplication for large (> 50% of intrathoracic stomach) type III-IV hiatus hernia. Data were extracted from hospital charts and a prospectively updated research database. The main study outcome was quality of life assessed by the Gastroesophageal reflux disease Health-Related Quality of Life (GERD-HRQL) score and the Short-form 36 (SF-36). RESULTS: Between 2013 and 2016, 37 out of 49 operated patients completed the comprehensive quality-of-life evaluation at the 2-year follow-up. The GERD-HRQL score significantly decreased compared to baseline (p < 0.001). All items of the SF-36 significantly improved compared to baseline (p < 0.05). Both Physical and Mental Component Summary scores were significantly higher than preoperative scores, with a medium Cohen's effect size (-0.77 and 0.56, respectively). At the 2-year follow-up, symptoms had disappeared in the majority of patients. The use of proton-pump inhibitors significantly decreased compared to baseline (13.5 vs. 86.4%, p < 0.001). Also, the use of antidepressants and benzodiazepines significantly decreased after surgery (8.1 vs. 32.4%, p < 0.001). The overall alimentary satisfaction score was > 8 in 92% of patients. There were no safety issues related to the use of the absorbable synthetic mesh. The incidence of anatomical hernia recurrence was 5.4%, but no patient with recurrent hernia required surgical revision. CONCLUSIONS: Laparoscopic repair of large hiatus hernia with mesh and partial fundoplication is associated with symptomatic relief, no side-effects, and a significant improvement in disease-specific and generic quality of life at 2-year follow-up.

Factors affecting the caloric and protein intake over time in critically ill trauma patients.

BACKGROUND: Major trauma leads to increased nutritional requirements. However, little is known about the actual amount of calories and protein administered and the factors affecting the intake over time in critically ill trauma patients. METHODS: Prospective study including 100 trauma patients admitted to the Los Angeles County + University of Southern California Medical Center intensive care unit between March 2014 and October 2014. Inclusion criteria were age > 16 y, surgery at admission, and no oral nutrition. The caloric and protein intake was recorded, and requirements were calculated daily for 28 d. The nutritional intake and the impact of clinical factors on the intake over time were assessed using mixed model analysis. RESULTS: The caloric and protein intake significantly increased over time, but the median intake did not meet the median calculated requirements at any time. Multivariable analysis revealed a smaller increase of the nutritional intake over time in patients with an injury severity score > 45, whereas penetrating injury and laparotomy were associated with a higher increase of the intake. Body mass index scores ≥ 30 kg/m2, traumatic brain injury, and gastrointestinal tract injuries were associated with a smaller increase of the caloric intake over time. CONCLUSIONS: The median nutritional intake did not meet the median calculated requirements over time. A smaller increase of the nutritional intake over time was found in patients with a higher injury burden, whereas penetrating injury and laparotomy were associated with a higher increase of the intake. Higher body mass index scores, traumatic brain injury, and gastrointestinal tract injuries were associated with a smaller increase of the caloric intake over time. These clinical factors can help to adjust the nutritional support in critically ill trauma patients.

Removal of the Magnetic Sphincter Augmentation Device: Surgical Technique and Results of a Single-center Cohort Study.

OBJECTIVE: The aim of this study was to identify patients' characteristics that may predict failure and removal of the Linx sphincter augmentation device, and to report the results of 1-stage laparoscopic removal and fundoplication. BACKGROUND: The Linx device is a long-term magnetic implant that was developed as a less disruptive and more reproducible surgical option for patients with early-stage gastroesophageal reflux disease (GERD). Removal of the device has been shown to be feasible, but no long-term results of this procedure have been reported yet. METHODS: A review of the prospectively collected research database of antireflux surgery was performed to identify all patients who underwent a Linx implant between 2007 and 2015 in our Institution. Demographics, duration of symptoms and proton pump inhibitor (PPI) therapy, GERD-Health Related Quality of Life scores, esophageal acid exposure, lower esophageal sphincter pressure, number of beads (size) of the implanted device, concurrent crura repair, angle of inclination of the device at postoperative chest film, operative time, postoperative complications, and length of stay were recorded. Data of the explanted patients were compared with those with the device in situ in an attempt to identify factors associated with Linx removal. RESULTS: Over the study period, 164 patients underwent a laparoscopic Linx implant and had a median follow-up of 48 months [interquartile range (IQR) 36]. Eleven (6.7%) of these patients were explanted at a later date. The estimated removal-free probability at 80 months was 0.91 [confidence interval (CI) 0.86-0.96]. Supine esophageal acid exposure before the index operation was associated with Linx removal (odds ratio 1.05, CI 1.01-1.11, P = 0.037). The main presenting symptom requiring device removal was recurrence of heartburn or regurgitation in 5 patients (46%), followed by dysphagia (n = 4, 37%) and chest pain (n = 2, 18%). In 2 patients, full-thickness erosion of the esophageal wall with partial endoluminal penetration of the device occurred. The median implant duration was 20 months, with 82% of the patients being explanted between 12 and 24 months after the implant. Device removal was most commonly combined with partial fundoplication. There were no conversions to laparotomy and the postoperative course was uneventful in all patients. At the latest follow-up, ranging from 12 to 58 months, the GERD-HRQL score was within normal limits in all patients. CONCLUSIONS: Laparoscopic removal of the Linx device can be safely performed as a 1-stage procedure and in conjunction with fundoplication even in patients presenting with device erosion.

Loss of muscle mass: a significant predictor of postoperative complications in acute diverticulitis.

BACKGROUND: Severe muscle mass depletion, sarcopenia, has been shown to be associated with poor operative outcomes. However, its impact on emergency abdominal operations remains unclear. The purpose of this study was to examine the association between low muscle mass (LMM) and outcomes after emergency operations for acute diverticulitis. PATIENTS AND METHODS: Patients ≥18 y requiring an emergency operation for acute diverticulitis between January 2007 and September 2014 were included. On preoperative computed tomography, the cross-sectional area (CSA) and transverse diameter (TVD) of the right and left psoas muscle were measured at the level of the third lumbar vertebral body. Sensitivity analysis was performed to determine appropriate CSA and TVD cutoff values defining low skeletal muscle mass. Clinical outcomes of patients with low muscle mass (LMM group) were compared with the non-LMM group. RESULTS: A total of 89 patients met our inclusion criteria. Median CSA and TVD were 794 mm2 and 24 mm, respectively. There was a strong correlation between the CSA and TVD (R2 = 0.84). In univariable analysis, significantly higher rates of postoperative major complications (63% versus 37%, P = 0.027) and surgical site infection (47% versus 19%, P = 0.008) were identified in the LMM group. After adjusting for clinically important covariates in a logistic regression model, patients with LMM were significantly associated with higher odds of major complications and surgical site infection. CONCLUSIONS: Preoperative assessment of the psoas muscle CSA and TVD on computed tomography can be a practical method for identifying patients at risk for postoperative complications.

Laparoscopic management of large hiatus hernia: five-year cohort study and comparison of mesh-augmented versus standard crura repair.

OBJECTIVES: To evaluate objective and subjective outcomes of patients undergoing laparoscopic repair of large hiatal hernia, either with or without resorbable mesh augmentation. The primary outcome of the study was anatomical recurrence rate as measured by endoscopy. Secondary outcomes were safety, efficacy, and long-term quality of life. METHODS: This was an observational cohort study. Patients who underwent laparoscopic repair of large (≥5 cm) type III hiatal hernia were included. Criteria of exclusion were previously failed hiatus hernia repair and emergency procedures. Patients were stratified into mesh group (mesh-augmented crura repair plus fundoplication) and non-mesh group (standard crura repair plus fundoplication). Preoperative and postoperative symptoms were assessed using the GERD-HRQL questionnaire. Upper gastrointestinal endoscopy was routinely performed between 6 and 12 months postoperatively and was repeated over the follow-up every 1-2 years or as needed. Anatomical hernia recurrence was defined as the maximum vertical length of stomach being at least 2 cm above the diaphragm. RESULTS: A total of 84 patients, 41 in the mesh group and 43 in the non-mesh group, operated between October 2009 and October 2014, were included in the study. All surgical procedures were completed laparoscopically. The median follow-up was 24 (IQR 29) months. There were 12 endoscopic recurrences, 4 in the mesh group and 8 in the non-mesh group. The five-year recurrence-free probability was similar in the two groups, but an earlier failure rate was noted in the non-mesh group at 12 months (p = 0.299). Three of the 12 patients with anatomical recurrence were symptomatic but did not require a reoperation. Univariate Cox proportional hazard analysis indicated that Toupet fundoplication may reduce the recurrence rate compared to Nissen fundoplication. No mesh-related complications occurred. CONCLUSIONS: Laparoscopic repair of large hiatal hernia is effective and durable. Crura reinforcement with a resorbable synthetic mesh is safe and may protect from early anatomical recurrence.

Prosthesis Complications in Elderly Patients: A Case of a Swallowed Overdenture.

Swallowed or aspirated dentures may result in serious systemic complications and require multidisciplinary attention or intervention. With an increasing number of edentulous elderly patients, such situations are not uncommon occurrences in everyday dentistry. In fact, dentures are the most ingested foreign body in the elderly patient population, and this is a particular risk if the dentures are lacking in stability. The present case report discusses the swallowing of an overdenture by a 95-year-old patient, who underwent endoscopic removal of the foreign body. The aim of this article is to highlight the risks of prosthetic restoration in older patients and the importance of thorough, scrupulous follow-up.

The Milan score: A novel manometric tool for a more efficient diagnosis of gastro-esophageal reflux disease.

OBJECTIVE: A definitive diagnosis of gastroesophageal reflux disease (GERD) depends on endoscopic and/or pH-study criteria. However, high resolution manometry (HRM) can identify factors predicting GERD, such as ineffective esophageal motility (IEM), esophago-gastric junction contractile integral (EGJ-CI), evaluating esophagogastric junction (EGJ) type and straight leg raise (SLR) maneuver response. We aimed to build and externally validate a manometric score (Milan Score) to stratify the risk and severity of the disease in patients undergoing HRM for suspected GERD. METHODS: A population of 295 consecutive patients undergoing HRM and pH-study for persistent typical or atypical GERD symptoms was prospectively enrolled to build a model and a nomogram that provides a risk score for AET > 6%. Collected HRM data included IEM, EGJ-CI, EGJ type and SLR. A supplemental cohort of patients undergoing HRM and pH-study was also prospectively enrolled in 13 high-volume esophageal function laboratories across the world in order to validate the model. Discrimination and calibration were used to assess model's accuracy. Gastroesophageal reflux disease was defined as acid exposure time >6%. RESULTS: Out of the analyzed variables, SLR response and EGJ subtype 3 had the highest impact on the score (odd ratio 18.20 and 3.87, respectively). The external validation cohort consisted of 233 patients. In the validation model, the corrected Harrel c-index was 0.90. The model-fitting optimism adjusted calibration slope was 0.93 and the integrated calibration index was 0.07, indicating good calibration. CONCLUSIONS: A novel HRM score for GERD diagnosis has been created and validated. The MS might be a useful screening tool to stratify the risk and the severity of GERD, allowing a more comprehensive pathophysiologic assessment of the anti-reflux barrier. TRIAL REGISTRATION: ClinicalTrials.gov (Identifier: NCT05851482).

Transoral stapling for Zenker diverticulum: effect of the traction suture-assisted technique on long-term outcomes.

BACKGROUND: Long-term outcomes and predictors of success after transoral stapling for Zenker diverticulum are still unclear. METHODS: Between 2001 and 2010, 91 patients with Zenker diverticulum underwent transoral stapling under general anesthesia. Since 2008, the technique was modified by applying traction sutures to ease engagement of the common septum inside the stapler jaws. Perioperative variables, distribution of symptoms, and outcome of surgery were analyzed. Long-term results were compared between patients undergoing standard versus modified technique of transoral stapling. RESULTS: The transoral approach was successfully completed in 79 (86.8 %) patients with a median age of 74 years. Overall morbidity was 5 %, and there was no mortality. The median length of hospital stay was 2 days. Six patients were lost to follow-up. After a median follow-up of 53 (range, 12-114) months, an improvement of dysphagia and regurgitation scores (p < 0.001) and a reduction in the number of pneumonia episodes per year (p < 0.001) was recorded. The long-term success rate of the procedure was 80.1 %. At a median time of 12 months, 14 patients complained of recurrent symptoms, 7 of whom needed an open (n = 4) or transoral (n = 3) reoperation. Use of traction sutures resulted in a greater long-term success compared with the standard procedure (p = 0.04). CONCLUSIONS: Transoral stapling is a safe and effective technique. A repeat procedure is feasible in case of recurrent diverticulum. The use of traction sutures applied at the apex of the common septum before stapling might increase the long-term success of the technique.

Tailored endoscopic treatment of tracheo-oesophageal fistula using preoperative holographic assessment and a cardiac septal occluder.

Devices originally designed for closure of cardiac septal defects have also been proposed for the treatment of acquired tracheo-oesophageal fistula (TOF). Choosing the right occluder device to match TOF size and shape is essential for a tailored treatment. We report the successful endoscopic closure of a post-radiotherapy TOF using preprocedural CT scan with holographic three-dimensional reconstruction and an Amplatzer atrial septal device. Complete TOF sealing was achieved with resolution of respiratory symptoms, and the patient was maintaining his ability to eat at 4-month follow-up.

Ventral hernia repair under neuraxial anesthesia.

BACKGROUND: Acute strangulated ventral hernia is associated with operative morbidity and mortality. General anesthesia may increase the operative risk, especially in morbidly obese and COVID-19-positive individuals. METHODS: A 67-year-old woman with body mass index (BMI) 51 kg/m2, hospitalized for SARS-CoV-2-related interstitial pneumonia and renal failure, presented with acute abdominal pain, nausea, vomiting, and abdominal tenderness secondary to giant ventral hernia strangulation. RESULTS: Due to the suspicion of vascular bowel compromise at contrast-enhanced CT scan, urgent open surgical repair surgery was performed under spinal anesthesia and Venturi mask support. There was no need for an intensive care unit (ICU) stay. Postoperative course was uneventful, and the patient was transferred to a rehabilitation center on postoperative day 10. CONCLUSION: Although some anesthetists and surgeons may be reluctant to use regional anesthesia for both emergent and elective ventral hernia repair, this may represent an excellent option in obese patients with a high respiratory risk.

Revisional Therapy for Recurrent Symptoms After Heller Myotomy for Achalasia.

PURPOSE: Symptom recurrence after initial surgical management of esophageal achalasia occurs in 10-25% of patients. The aim of this study was to analyze safety and efficacy of revisional therapy after failed Heller myotomy (HM). METHODS: A retrospective review of a prospective database was performed searching for patients with recurrent symptoms after primary surgical therapy for achalasia. Patients with previously failed HM were considered for the final analysis. The Foregut questionnaire, and the Atkinson and Eckardt scales were used to assess severity of symptoms. Objective investigations routinely included upper gastrointestinal endoscopy and barium swallow study. Redo treatments consisted of endoscopic pneumatic dilation (PD), laparoscopic HM, hybrid Ivor Lewis esophagectomy, or stapled cardioplasty. A yearly clinical and endoscopic follow-up was scheduled in all patients. RESULTS: Over a 20-year period, 26 patients with a median age of 66 years (IQR 19.5) underwent revisional therapy after failed HM for achalasia at a tertiary-care university hospital. The median time after index procedure was 10 years (IQR 21). Revisional therapy consisted of endoscopic pneumatic dilation (n=13), laparoscopic HM and fundoplication (n=10), esophagectomy (n=2), and stapled cardioplasty and fundoplication (n=1). Nine (34.6%) of these patients required further endoscopic or surgical treatments. There was no mortality, and the overall complication rate was 7.7%. At a median follow-up of 42 months (range 10-149), a significant decrease of dysphagia, regurgitation, chest pain, respiratory symptoms, and median Eckardt score (p<0.05) was noted. CONCLUSION: In specialized and multidisciplinary centers, revisional therapy for achalasia is feasible, safe, and effective.

Reference high-resolution manometry values after magnetic sphincter augmentation.

BACKGROUND: Magnetic sphincter augmentation (MSA) is an innovative antireflux procedure that can improve lower esophageal sphincter (LES) competency and reduce symptoms of gastroesophageal reflux disease (GERD). Some patients report postoperative dysphagia. To date, no studies have described reference high-resolution manometry (HRM) values after MSA implantation. METHODS: High-resolution manometry was performed in patients free of dysphagia after MSA with or without concurrent crura repair. Reference values for all parameters of the Chicago Classification were defined as those between the 5th and 95th percentiles. The contribution of concurrent crura repair to LES competency and to reference values was also analyzed. KEY RESULTS: Eighty-four patients met the study inclusion criteria. The upper limit of normality for integrated relaxation pressure (IRP) and intrabolus pressure (IBP) was 20.2 mmHg and 30.3 mmHg, respectively. Both variables were higher after MSA compared to normative Chicago Classification v3.0 values. The Distal Contractile Integral upper limit was in the range of normality. Patients undergoing crura repair had a significantly higher IRP (p = 0.0378) and lower GERDQ-A scores (p = 0.0374) and Reflux Symptom Index (p = 0.0030) compared to those who underwent MSA device implantation alone. CONCLUSION & INFERENCES: This study provides HRM reference values for patients undergoing successful MSA implantation. Crural repair appears to be a key component of LES augmentation and is associated with improved clinical outcomes.