Safety and efficacy of magnetic sphincter augmentation dilation

The magnetic sphincter augmentation device (MSA) provides effective relief of gastroesophageal reflux symptoms. Dysphagia after MSA implantation sometimes prompts endoscopic dilation. The manufacturer's instructions are that it be performed 6 or more weeks after implantation under fluoroscopic guidance to not more than 15 mm keeping 3 or more beads closed. The purpose of this study was to assess adherence to these recommendations and explore the techniques used and outcomes after MSA dilation.

We conducted a multicenter retrospective review of patients undergoing dilation for dysphagia after MSA placement from 2012 to 2018.

A total of 144 patients underwent 245 dilations. The median size of MSA placed was 14 beads (range 12-17) and the median time to dilation was 175 days. A second dilation was performed in 67 patients, 22 patients had a third dilation and 7 patients underwent 4 or more dilations. In total, 17 devices (11.8%) were eventually explanted. The majority of dilations were performed with a balloon dilator (81%). The median dilator size was 18 mm and 73.4% were done with a dilator larger than 15 mm. There was no association between dilator size and need for subsequent dilation. Fluoroscopy was used in 28% of cases. There were no perforations or device erosions related to dilation.

There is no clinical credence to the manufacturer's recommendation for the use of fluoroscopy and limitation to 15 mm when dilating a patient for dysphagia after MSA implantation. Use of a larger size dilator was not associated with perforation or device erosion, but also did not reduce the need for repeat dilation. Given this, we would recommend that the initial dilation for any size MSA device be done using a 15 mm through-the-scope balloon dilator. Dysphagia prompting dilation after MSA implantation is associated with nearly a 12% risk of device explantation.