title: Transoral endoscopic fundoplication in the treatment of gastroesophageal reflux disease: the anatomic and physiologic basis for reconstruction of the esophagogastric junction using a novel device.
abstract: OBJECTIVE
  To determine the safety, mechanism of action, immediate postprocedural anatomic impact on the esophagogastric junction, and short-term efficacy of the first entirely endolumenal antireflux procedure.
  
  
  BACKGROUND
  A safe and effective endoscopic antireflux procedure remains elusive. Transoral endolumenal surgery has enormous potential for the treatment of gastroesophageal reflux disease (GERD) and other esophagogastric diseases. A canine model was used to study a novel endoscopic device, which allows for creation of an endoluminal fundoplication.
  
  
  METHODS
  The transoral incisionless fundoplication (TIF) was performed in 21 canines in a phase I feasibility and safety study, and in 21 canines in a phase II study that included a detailed objective assessment of the effects of 2 variants of the TIF procedure (TIF 1.0 and TIF 2.0) versus sham on esophageal physiology and esophagogastric junction (EGJ) anatomy.
  
  
  RESULTS
  In phase I, TIF provided a safe and feasible endolumenal therapy for GERD, with histologic data that demonstrated serosal fusion of approximated full-thickness tissue plications and durability of the fundoplication. TIF procedures effectively reduced cardia circumference and improved Hill classification grade. In phase II, the TIF 2.0 procedure achieved normalization of distal esophageal acid exposure and increased lower esophageal sphincter (LES) pressure and length based on objective testing over a 2-week period. TIF 2.0 demonstrated superior results to TIF 1.0, and valve appearance and location exhibited similarity to the Nissen fundoplication by vector volume analysis.
  
  
  CONCLUSIONS
  The TIF procedure is safe and results in a durable and functional fundoplication as well as a platform for further development and modification of the procedure, which can be use to impact outcome. This work provides the foundation for human translation and assessment of long-term outcomes.
authors.affiliation: Division of Thoracic and Foregut Surgery, Heart, Lung and Esophageal Surgery Institute, University of Pittsburgh, Pittsburgh, Pennsylvania 15232, USA. jobeba@upmc.edu
authors.forename: Blair A
authors.initials: BA
authors.lastname: Jobe
authors.forename: Robert W
authors.initials: RW
authors.lastname: O'Rourke
authors.forename: Barry P
authors.initials: BP
authors.lastname: McMahon
authors.forename: Flemming
authors.initials: F
authors.lastname: Gravesen
authors.forename: Cedric
authors.initials: C
authors.lastname: Lorenzo
authors.forename: John G
authors.initials: JG
authors.lastname: Hunter
authors.forename: Mary
authors.initials: M
authors.lastname: Bronner
authors.forename: Stefan J M
authors.initials: SJ
authors.lastname: Kraemer
mesh_terms: D000818:Animals; D004285:Dogs; D004724:Endoscopy; D004943:Esophagogastric Junction / Q000601:surgery*; D018662:Fundoplication / Q000379:methods*; D005764:Gastroesophageal Reflux / Q000601:surgery*; D008365:Manometry