title: Evaluation of esophagogastric junction relaxation by 4-second Integrated Relaxation Pressure in achalasia using High Resolution Manometry with water-perfused catheters.
abstract: BACKGROUND
  Relaxation of the esophagogastric junction (EGJ) is now evaluated calculating 4-second integrated relaxation pressure (4-s IRP) by high resolution manometry (HREPT). Solid-state catheters have been used to define abnormal values. Our aim was to evaluate 4-s IRP in esophageal achalasia using HREPT with perfused catheters.
  
  
  METHODS
  From June 2009 to June 2013, 936 HREPT studies have been performed in our unit. Of these, 194 patients having treated achalasia were excluded. Control group was constituted by 695 patients without achalasia, and 47 patients with untreated achalasia constituted the study group. HREPT was performed with water-perfused catheters. To establish the cut-off value for 4-s IRP that better discriminate patients with achalasia from all other patients, a receiver operating characteristic (ROC) analysis was performed.
  
  
  RESULTS
  Twenty three of 47 achalasia patients (49%) showed a 4-s IRP under 15 mmHg; and seven (15%) had a value under modified Chicago criteria. A cut-off value for 4-s IRP of 6.5 mmHg, calculated by ROC analysis, highly discriminates achalasia from the rest of the patients and especially from scleroderma patients (area under the curve: 0.997, 95% CI: 0.995-1.000; p < 0.001).
  
  
  CONCLUSIONS
  Cut-off values for 4-s IRP defined using HREPT with solid-state catheters are not adequate for diagnosing esophageal achalasia with water-perfused systems. A lower value, i.e., 6.5 mmHg, is suggested for this equipment. The diagnostic criteria of esophageal achalasia should be modified for HREPT performed with water-perfused systems.
authors.affiliation: Digestive Functional Disorders Unit, Gastroenterology Department, Hospital Universitari i Politècnic La Fe, Valencia, Spain.
authors.forename: V
authors.initials: V
authors.lastname: Ortiz
authors.forename: G
authors.initials: G
authors.lastname: Poppele
authors.forename: N
authors.initials: N
authors.lastname: Alonso
authors.forename: C
authors.initials: C
authors.lastname: Castellano
authors.forename: V
authors.initials: V
authors.lastname: Garrigues
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019540:Area Under Curve; D057785:Catheters; D004931:Esophageal Achalasia / Q000175:diagnosis*; D004943:Esophagogastric Junction / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D008365:Manometry / Q000295:instrumentation / Q000379:methods*; D008875:Middle Aged; D009126:Muscle Relaxation / Q000502:physiology; D009130:Muscle, Smooth / Q000503:physiopathology; D011312:Pressure; D012372:ROC Curve; D012016:Reference Values; D014867:Water; D055815:Young Adult
chemical_list: D014867:Water
keywords: achalasia; esophageal manometry; esophagogastric junction relaxation; high resolution manometry; lower esophageal sphincter relaxation; scleroderma