title: Pathophysiology of Gastroesophageal Reflux Disease.
abstract: Gastroesophageal reflux disease pathophysiology is multifactorial and linked to a misbalance between the aggressiveness of the refluxate into the esophagus or adjacent organs and the failure of protective mechanisms associate or not to a defective valvular mechanism at the level of the esophagogastric junction incapable of dealing with a transdiaphragmatic pressure gradient. Antireflux mechanisms include the lower esophageal sphincter and abdominal esophagus, the diaphragm, the angle of His, the Gubaroff valve, and the phrenoesophageal membrane. Protective mechanisms include esophageal motility, saliva production, and epithelial protection. Disruption of this balance occurs most commonly due to the presence of a hiatal hernia, esophageal dysmotility, a rise in abdominal pressure (obesity), and decrease in thoracic pressure (chronic lung diseases).
authors.affiliation: Department of Surgery, State University of Londrina, Londrina, Brazil.
authors.forename: Mariano A
authors.initials: MA
authors.lastname: Menezes
authors.affiliation: Department of Surgery, Escola Paulista de Medicina, Federal University of São Paulo, Rua Diogo de Faria 1087 cj 301, São Paulo, SP, 04037-003, Brazil. herbella.dcir@epm.br.
authors.forename: Fernando A M
authors.initials: FAM
authors.lastname: Herbella
mesh_terms: D049630:Esophageal Sphincter, Lower / Q000503:physiopathology; D004943:Esophagogastric Junction / Q000503:physiopathology; D005764:Gastroesophageal Reflux / Q000209:etiology / Q000503:physiopathology*; D006551:Hernia, Hiatal / Q000503:physiopathology; D006801:Humans; D011312:Pressure