title: Vigor of peristalsis during multiple rapid swallows is inversely correlated with acid exposure time in patients with NERD.
abstract: BACKGROUND
  Multiple rapid swallowing (MRS) during high-resolution manometry (HRM) is increasingly utilized as provocative test to assess esophageal peristaltic reserve. The aim of this study was to evaluate the correlation between MRS response and impedance and pH (MII-pH) parameters in endoscopy negative heartburn (ENH) patients.
  
  
  METHODS
  We enrolled consecutive ENH patients, who underwent HRM and MII-pH study, with a selected MII-pH profile: abnormal MII-pH (pH+/MII+); normal MII-pH (pH-/MII-). HRM was performed with 10 wet swallows (WS) and one MRS. Mean distal contractile integral (DCI) during WS and MRS were calculated. MII-pH parameters including acid exposure time (AET), reflux events, baseline impedance levels (BI) and the efficacy of chemical clearance evaluated with the postreflux swallow-induced peristaltic wave (PSPW) index were measured.
  
  
  RESULTS
  We analyzed 103 patients: 49 MII+/pH+ (27 male), and 54 MII-/pH- (19 male). Mean age was similar between the two groups. As expected, mean AET and number of refluxes were higher in pH+/MII+ (p < 0.05). HRM was normal in all selected patients. Mean DCI-WS was similar between two groups (p = n.s.). Mean DCI-MRS- was higher in MII-/pH- vs MII+/pH+ (p < 0.05). The increase in DCI-MRS was inversely correlated with AET (-0.699; p < 0.001) and directly correlated with BI values (0.631; p < 0.001) and PSPW index (0.626; p < 0.001).
  
  
  CONCLUSIONS
  Following MRS, patients with abnormal impedance-pH test showed suboptimal contraction response as compared with those with normal impedance-pH test. Moreover, MRS response was inversely correlated with AET and directly correlated with BI values and PSPW index.
authors.affiliation: Division of Gastroenterology, Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy.
authors.forename: I
authors.initials: I
authors.lastname: Martinucci
authors.affiliation: Division of Gastroenterology, Department of Surgery, Oncology and Gastroenterology, University of Padua, Padua, Italy.
authors.forename: E V
authors.initials: EV
authors.lastname: Savarino
authors.affiliation: Gastroenterology Unit, Department of Internal Medicine, Northwest University, Chicago, IL, USA.
authors.forename: J E
authors.initials: JE
authors.lastname: Pandolfino
authors.affiliation: Division of Gastroenterology, Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Russo
authors.affiliation: Division of Gastroenterology, Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Bellini
authors.affiliation: Division of Surgery, Department of Surgery, Second University of Naples, Naples, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Tolone
authors.affiliation: Gastroenterology Unit, University Hospital of Bern, Bern, Switzerland.
authors.forename: R
authors.initials: R
authors.lastname: Tutuian
authors.affiliation: Digestive Physiology, Hospices Civil de Lyon and Lyon I University, Lyon, France.
authors.forename: S
authors.initials: S
authors.lastname: Roman
authors.affiliation: Division of Gastroenterology, Department of Internal Medicine (DIMI), University of Genoa, Genoa, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Furnari
authors.affiliation: Gastroenterology Digestive Pathophysiology Unit, Baggiovara Hospital, Modena, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Frazzoni
authors.affiliation: Gastroenterology Unit, University Hospital of Bern, Bern, Switzerland.
authors.forename: L
authors.initials: L
authors.lastname: Macchia
authors.affiliation: Division of Gastroenterology, Department of Internal Medicine (DIMI), University of Genoa, Genoa, Italy.
authors.forename: V
authors.initials: V
authors.lastname: Savarino
authors.affiliation: Division of Gastroenterology, Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Marchi
authors.affiliation: Division of Gastroenterology, Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy.
authors.forename: N
authors.initials: N
authors.lastname: de Bortoli
mesh_terms: D000328:Adult; D003679:Deglutition / Q000502:physiology*; D017097:Electric Impedance; D050782:Esophageal pH Monitoring; D005260:Female; D005764:Gastroesophageal Reflux / Q000503:physiopathology*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008297:Male; D008365:Manometry; D008875:Middle Aged; D010528:Peristalsis / Q000502:physiology*
keywords: acid exposure time; gastro-esophageal reflux disease; high-resolution manometry; multiple rapid swallow