title: Prolonged measurement improves the assessment of the barrier function of the esophago-gastric junction by high-resolution manometry.
abstract: BACKGROUND
  Etiology of gastro-esophageal reflux disease (GERD) is multifactorial, but incompetence of the esophago-gastric junction (EGJ) appears to be of crucial importance. Established manometric parameters for assessment of EGJ barrier function are sub-optimal, potentially because they reflect only a very brief (up to 30 seconds), not necessarily representative period. This prospective, case-control study tested the performance of novel, high-resolution manometry (HRM) parameters of EGJ function in the assessment of GERD.
  
  
  METHODS
  Patients with reflux symptoms and healthy controls (HC) underwent standard HRM and 24-hour pH±impedance measurements. EGJ morphology, lower esophageal sphincter pressure integral (LES-PI), EGJ contractile integral (EGJ-CI) were compared with total-EGJ-CI, a novel parameter summarizing EGJ barrier function during the entire HRM protocol. Esophageal acid exposure ≥4.2%/24 h (A-Reflux-pos) or ≥73 reflux episodes in 24 hours (V-Reflux-pos) were considered pathological.
  
  
  RESULTS
  Sixty five HC and 452 patients completed HRM, 380 (84%) patients underwent ambulatory reflux-monitoring. LES-PI, EGJ-CI and total-EGJ-CI correlated with EGJ morphology subtypes (all P<.00001). Only total-EGJ-CI was consistently lower in A-Reflux-pos and V-Reflux-pos subjects compared with HC and patients without GERD. Total-EGJ-CI was also the single best parameter for prediction of pathological reflux (optimal cut-off 47 mmHg cm, AUC 0.746, P<.0001). This cut-off value, approximately 1 SD below the mean normal value, showed modest sensitivity 54% and positive predictive value 46%, but good specificity 85% and negative predictive value 89% for GERD diagnosis.
  
  
  CONCLUSIONS
  Total EGJ-CI, a new metric that summarizes EGJ contractility over time, allows an improved assessment of EGJ barrier function. Pathological reflux is unlikely if this metric is within the upper two-thirds of the normal range.
authors: Department of Internal Medicine, Israelitic Hospital, Academic Hospital of the University of Hamburg, Hamburg, Germany.
authors: D
authors: D
authors: Jasper
authors: Department of Gastroenterology, University of São Paulo, School of Medicine, São Paulo, Brazil.
authors: N
authors: N
authors: Freitas-Queiroz
authors: Department of Gastroenterology and Hepatology, University Hospital of Zurich, Zurich, Switzerland.
authors: M
authors: M
authors: Hollenstein
authors: Department of Gastroenterology and Hepatology, University Hospital of Zurich, Zurich, Switzerland.
authors: B
authors: B
authors: Misselwitz
authors: Department of Internal Medicine, Israelitic Hospital, Academic Hospital of the University of Hamburg, Hamburg, Germany.
authors: P
authors: P
authors: Layer
authors: Department of Gastroenterology, University of São Paulo, School of Medicine, São Paulo, Brazil.
authors: T
authors: T
authors: Navarro-Rodriguez
authors: Department of Gastroenterology and Hepatology, University Hospital of Zurich, Zurich, Switzerland.|Department of Gastroenterology, Abdominal Center, St. Claraspital, Basel, Switzerland.
authors: M
authors: M
authors: Fox
authors: Department of Internal Medicine, Israelitic Hospital, Academic Hospital of the University of Hamburg, Hamburg, Germany.
authors: J
authors: J
authors: Keller
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D004943:Esophagogastric Junction / Q000502:physiology*; D005260:Female; D005764:Gastroesophageal Reflux / Q000175:diagnosis* / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008365:Manometry / Q000379:methods* / Q000592:standards; D008875:Middle Aged; D011446:Prospective Studies; D013997:Time Factors
keywords: 
  GERD
  ; esophageal motility disorders; esophago-gastric junction; hiatal hernia; high-resolution manometry; pH-monitoring