Manometric Changes to the Lower Esophageal Sphincter After Magnetic Sphincter Augmentation in Patients With Chronic Gastroesophageal Reflux Disease
To evaluate the manometric changes, function, and impact of magnetic sphincter augmentation (MSA) on the lower esophageal sphincter (LES).Background:
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.Methods:
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/m2, 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.Results:
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).Results:
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.Conclusion:
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.