A systematic review and meta-analysis examined patients who received magnetic sphincter augmentation (MSA) after laparoscopic sleeve gastrectomy. The study included 287 patients across multiple institutions and compared them to nonbariatric populations. Researchers found that the overall device erosion rate was 3.8 percent. This rate was significantly higher than in nonbariatric groups, though it remained below four percent with proper patient selection. The average time to erosion was 18 months.
Several factors increased the risk of erosion. Having a body mass index over 30 kg/m2 raised the odds by 3.2 times. Not performing a hiatal repair increased the odds by 4.1 times. Using an undersized device raised the odds by 3.8 times. Persistent sleeve dilatation also increased the risk by 2.7 times.
Most patients who experienced erosion showed symptoms like difficulty swallowing. When the device was removed, 90.9 percent of patients saw their symptoms resolve. The study notes that this erosion risk must be weighed against the complication rates of converting to a Roux-en-Y gastric bypass. The evidence has very low to low certainty, and recommendations need more prospective validation.