Need for frequent dilations after magnetic sphincter augmentation: an assessment of associated factors and outcomes

Background: Dysphagia is the most common complaint after magnetic sphincter augmentation (MSA), with nearly one-third of patients requiring at least one dilation following MSA. A subset of patients require frequent dilations, but there is a paucity of data on the characteristics of this population. This study aimed to identify predictors of the need for frequent dilations within the first year after implant and to assess these patients' outcomes.

Methods: This is a retrospective review of prospectively collected data of patients who underwent MSA over an 8-year period. Frequent dilations were defined as 2 or more dilations within 1 year of surgery. Patients completed baseline and 1-year postoperative GERD-HRQL questionnaires and objective physiology testing. Baseline demographic, clinical characteristics, and objective testing data were compared between patients who did and did not require frequent dilations.

Results: A total of 697 (62.7% female) patients underwent MSA, with 62 (8.9%) patients requiring frequent dilation. At a mean (SD) of 12.3 (3.4) months follow-up, the frequent dilation group had higher median GERD-HRQL total scores (21.0 vs. 5.0, p < 0.001), PPI use (20.8% vs.10.1%, p = 0.023), dissatisfaction (46.7% vs. 11.6%, p < 0.001), and device removal (25.8% vs. 2.2%, p < 0.001) rates. Acid normalization was comparable (p = 0.997). Independent predictors of frequent dilation included preoperative odynophagia (OR 2.85; p = 0.001), IRP > 15 mmHg (OR 2.88; p = 0.006), and > 30% incomplete bolus clearance (OR 1.94; p = 0.004). At a mean (SD) of 15.7 (10.7) months, 28 (45.1%) patients underwent device removal after frequent dilation. Independent predictors of device removal after frequent dilation within 5 years of surgery were preoperative odynophagia (OR 7.18; p = 0.042), LES resting pressure > 45 mmHg (OR 28.5; p = 0.005), and ≥ 10% failed swallows (OR 23.5; p < 0.001).

Conclusions: The need for frequent dilations after MSA is a marker for poor symptom control, dissatisfaction, and device removal. Patients with preoperative odynophagia, high LES pressures, and poor esophageal motility should be counseled of their risk for these poor outcomes.