title: Manometric Changes to the Lower Esophageal Sphincter After Magnetic Sphincter Augmentation in Patients With Chronic Gastroesophageal Reflux Disease.
abstract: To evaluate the manometric changes, function, and impact of magnetic sphincter augmentation (MSA) on the lower esophageal sphincter (LES).
  
  
  
  Implantation of a MSA around the gastroesophageal junction has been shown to be a safe and effective therapy for gastroesophageal reflux disease, but its effect on the LES has not been elucidated.
  
  
  
  Retrospective case control study (n = 121) evaluating manometric changes after MSA. Inclusion criteria consisted of a confirmed diagnosis of gastroesophageal reflux disease by an abnormal esophageal pH study (body mass index <35 kg/m, hiatal hernia <3 cm, and absence of endoscopic Barrett disease). Manometric changes, pH testing, and proton pump inhibitor use were assessed preoperatively and 6 and 12 months after MSA.
  
  
  
  MSA was associated with an overall increase in the median LES resting pressure (18 pre-MSA vs 23 mm Hg post-MSA; P = 0.0003), residual pressure (4 vs 9 mm Hg; P < 0.0001), and distal esophageal contraction amplitude (80 vs 90 mm Hg; P = 0.02). The percent peristalsis remained unaltered (94% vs 87%; P = 0.71).Overall, patients with a manometrically defective LES were restored 67% of the time to a normal sphincter with MSA. Those with a structurally defective or severely defective LES improved to a normal LES in 77% and 56% of patients, respectively. Only 18% of patients with a normal preoperative manometric LES deteriorated to a lower category.
  
  
  
  MSA results in significant manometric improvement of the LES without apparent deleterious effects on the esophageal body. A manometrically defective LES can be restored to normal sphincter, whereas a normal LES remains stable.
authors.affiliation: Division of Thoracic Surgery, Swedish Medical Center, Seattle, WA.
authors.forename: Heather F
authors.initials: HF
authors.lastname: Warren
authors.forename: Brian E
authors.initials: BE
authors.lastname: Louie
authors.forename: Alexander S
authors.initials: AS
authors.lastname: Farivar
authors.forename: Candice
authors.initials: C
authors.lastname: Wilshire
authors.forename: Ralph W
authors.initials: RW
authors.lastname: Aye
mesh_terms: D000328:Adult; D049630:Esophageal Sphincter, Lower / Q000503:physiopathology* / Q000601:surgery*; D005260:Female; D005764:Gastroesophageal Reflux / Q000503:physiopathology* / Q000601:surgery*; D006801:Humans; D055909:Magnetic Field Therapy / Q000295:instrumentation*; D008297:Male; D008365:Manometry; D008875:Middle Aged; D011312:Pressure; D019736:Prostheses and Implants; D012189:Retrospective Studies; D016896:Treatment Outcome