Yadlapati, Rena

Abstract Chicago Classification v4.0 (CCv4.0) is the updated classification scheme for esophageal motility disorders using metrics from high‐resolution manometry (HRM). Fifty‐two diverse international experts separated into seven working subgroups utilized formal validated methodologies over two‐years to develop CCv4.0. Key updates in CCv.4.0 consist of a more rigorous and expansive HRM protocol that incorporates supine and upright test positions as well as provocative testing, a refined definition of esophagogastric junction (EGJ) outflow obstruction (EGJOO), more stringent diagnostic criteria for ineffective esophageal motility and description of baseline EGJ metrics. Further, the CCv4.0 sought to define motility disorder diagnoses as conclusive and inconclusive based on associated symptoms, and findings on provocative testing as well as supportive testing with barium esophagram with tablet and/or functional lumen imaging probe. These changes attempt to minimize ambiguity in prior iterations of Chicago Classification and provide more standardized and rigorous criteria for patterns of disorders of peristalsis and obstruction at the EGJ.

The functional lumen imaging probe (FLIP) measures luminal dimensions using impedance planimetry, performed most often during sedated upper endoscopy. Mechanical properties of the esophageal wall and opening dynamics of the esophagogastric junction (EGJ) can be objectively evaluated in esophageal motor disorders, eosinophilic esophagitis, esophageal strictures, during esophageal surgery and in postsurgical symptomatic states. Distensibility index, the ratio of EGJ cross sectional area to intraballoon pressure, is the most useful FLIP metric. Secondary peristalsis from balloon distension can be displayed topographically as repetitive anterograde or retrograde contractile activity in the esophageal body, similar to high-resolution manometry. Real-time interpretation and postprocessing of FLIP metadata can complement the identification of esophageal outflow obstruction and achalasia, especially when findings are inconclusive from alternate esophageal tests in symptomatic patients. FLIP can complement the diagnosis of achalasia when manometry and barium studies are inconclusive or negative in patients with typical symptoms. FLIP can direct adequacy of disruption of the EGJ in achalasia when used during and immediately after myotomy and pneumatic dilation. Lumen diameter measured using FLIP in eosinophilic esophagitis and in complex strictures can potentially guide management. An abbreviated modification of the Grading of Recommendations Assessment, Development, and Evaluation was used to determine the quality of available evidence and recommendations regarding FLIP utilization. FLIP metrics that are diagnostic or suggestive of an abnormal motor pattern and metrics that define normal esophageal physiology were developed by consensus and are described in this review.

AbstractBackgroundAn international group of experts evaluated and revised recommendations for ambulatory reflux monitoring for the diagnosis of gastro‐esophageal reflux disease (GERD).MethodsLiterature search was focused on indications and technical recommendations for GERD testing and phenotypes definitions. Statements were proposed and discussed during several structured meetings.Key ResultsReflux testing should be performed after cessation of acid suppressive medication in patients with a low likelihood of GERD. In this setting, testing can be either catheter‐based or wireless pH‐monitoring or pH‐impedance monitoring. In patients with a high probability of GERD (esophagitis grade C and D, histology proven Barrett's mucosa >1 cm, peptic stricture, previous positive pH monitoring) and persistent symptoms, pH‐impedance monitoring should be performed on treatment. Recommendations are provided for data acquisition and analysis. Esophageal acid exposure is considered as pathological if acid exposure time (AET) is greater than 6% on pH testing. Number of reflux episodes and baseline impedance are exploratory metrics that may complement AET. Positive symptom reflux association is defined as symptom index (SI) >50% or symptom association probability (SAP) >95%. A positive symptom‐reflux association in the absence of pathological AET defines hypersensitivity to reflux.Conclusions and InferencesThe consensus group determined that grade C or D esophagitis, peptic stricture, histology proven Barrett's mucosa >1 cm, and esophageal acid exposure greater >6% are sufficient to define pathological GERD. Further testing should be considered when none of these criteria are fulfilled.

AbstractBackgroundCompetent interpretation of esophageal high‐resolution manometry (HRM) is integral to a quality study. Currently, methods to assess physician competency for the interpretation of esophageal HRM do not exist. The aim of this study was to use formal techniques to (i) develop an HRM interpretation exam, and (ii) establish minimum competence benchmarks for HRM interpretation skills at the trainee, physician interpreter, and master level.MethodsA total of 29 physicians from 8 academic centers participated in the study: 9 content experts separated into 2 study groups—expert test‐takers (n=7) and judges (n=2), and 20 HRM inexperienced trainees (“trainee test‐taker”; n=20). We designed the HRM interpretation exam based on expert consensus. Expert and trainee test‐takers (n=27) completed the exam. According to the modified Angoff method, the judges reviewed the test‐taker performance and established minimum competency cut scores for HRM interpretation skills.Key ResultsThe HRM interpretation exam consists of 22 HRM cases with 8 HRM interpretation skills per case: identification of pressure inversion point, hiatal hernia >3 cm, integrated relaxation pressure, distal contractile integral, distal latency, peristaltic integrity, pressurization pattern, and diagnosis. Based on the modified Angoff method, minimum cut scores for HRM interpretation skills at the trainee, physician interpreter, and master level ranged from 65–80%, 85–90% (with the exception of peristaltic integrity), and 90–95%, respectively.Conclusions & InferencesUsing a formal standard setting technique, we established minimum cut scores for eight HRM interpretation skills across interpreter levels. This examination and associated cut scores can be applied in clinical practice to judge competency.