title: Physiology of diffuse esophageal spasm (DES)--when normal swallows are not normal.
abstract: BACKGROUND
  Diffuse esophageal spasm (DES) is characterized on manometry by a combination of simultaneous contractions and normal swallows. The aim of this study was to examine the manometric characteristics of simultaneous and 'normal' swallows in patients with DES patients compared with normal controls.
  
  
  METHODS
  Manometric studies from 69 patients with DES and 20 controls were analysed to determine the proportion of normal, hypertensive, ineffective and simultaneous contractions, and the velocity of propagation along the esophagus, the duration and amplitude of contraction and the relaxation characteristics (nadir and duration) of the lower esophageal sphincter.
  
  
  RESULTS
  The propagation velocity was the only significant difference between normal swallows and simultaneous contractions in DES patients (middle third: 49.2 VS 101.2 mm s(-1), P ≤ 0.001 lower third: 44.1 VS 88.7 mm s(-1), P ≤ 0.001). 'Normal' swallows in patients with DES had a greater velocity of propagation than those in age-matched control subjects (middle third: 49.2 VS 37.0 mm s(-1), P = 0.02, lower third: 44.1 VS 23.3 mm s(-1), P ≤ 0.001).
  
  
  CONCLUSIONS
  As expected, simultaneous contractions of DES patients differ from 'normal' swallows in DES patients mainly regarding the velocity of propagation of contraction but are similar in amplitude, however 'normal' swallows of DES patients are also more rapidly propagated along the esophagus than normal swallows of a control group suggesting that all swallows in DES are affected to some degree by the same process.
authors.affiliation: Department of Gastroenterology, The Royal Melbourne Hospital, Melbourne, Australia. claudiagruebel@bluewin.ch
authors.forename: C
authors.initials: C
authors.lastname: Krieger-Grübel
authors.forename: R
authors.initials: R
authors.lastname: Hiscock
authors.forename: S
authors.initials: S
authors.lastname: Nandurkar
authors.forename: R
authors.initials: R
authors.lastname: Heddle
authors.forename: G
authors.initials: G
authors.lastname: Hebbard
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003627:Data Interpretation, Statistical; D003679:Deglutition / Q000502:physiology*; D003680:Deglutition Disorders / Q000503:physiopathology*; D015155:Esophageal Spasm, Diffuse / Q000503:physiopathology*; D004947:Esophagus / Q000503:physiopathology; D005260:Female; D006801:Humans; D008297:Male; D008365:Manometry; D008875:Middle Aged; D009119:Muscle Contraction / Q000502:physiology; D010528:Peristalsis / Q000502:physiology; D055815:Young Adult