GERD after Peroral Endoscopic Myotomy: Assessment of Incidence and Predisposing Factors

Abstract

Background: Peroral endoscopic myotomy (POEM) is an effective intervention for achalasia, but GERD is a major postoperative adverse event. This study aimed to characterize post-POEM GERD and identify preoperative or technical factors impacting development or severity of GERD.

Study design: This is a retrospective review of patients who underwent POEM at our institution. Favorable outcome was defined as postoperative Eckardt score of 3 or less. Subjective GERD was defined as symptoms consistent with reflux. Objective GERD was based on a DeMeester score greater than 14.7 or Los Angeles grade C or D esophagitis. Severe GERD was defined as a DeMeester score greater than 50.0 or Los Angeles grade D esophagitis Preoperative clinical and objective data and technical surgical elements were compared between those with and without GERD. Multivariate logistic analysis was performed to identify factors associated with each GERD definition.

Results: A total of 183 patients underwent POEM. At a mean ± SD follow-up of 21.7 ± 20.7 months, 93.4% achieved favorable outcome. Subjective, objective, and severe objective GERD were found in 38.8%, 50.5%, and 19.2% of patients, respectively. Of those with objective GERD, 24.0% had no reflux symptoms. Women were more likely to report GERD symptoms (p = 0.007), but objective GERD rates were similar between sexes (p = 0.606). The independent predictors for objective GERD were normal preoperative diameter of esophagus (odds ratio [OR] 3.4; p = 0.008) and lower esophageal sphincter (LES) pressure less than 45 mmHg (OR 1.86; p = 0.027). The independent predictors for severe objective GERD were LES pressure less than 45 mmHg (OR 6.57; p = 0.007) and obesity (OR 5.03; p = 0.005). The length of esophageal or gastric myotomy or indication of procedure had no impact on the incidence or severity of GERD.

Conclusion: The rate of pathologic GERD after POEM is higher than symptomatic GERD. A nonhypertensive preoperative LES is a predictor for post-POEM GERD. No modifiable factors impact GERD after POEM.

Graphical abstract

Figure 1.

Postoperative DeMeester score by indication of procedure. The black middle line denotes the median DeMeester score for achalasia types 1, 2, and 3, esophagogastric junction outlet obstruction (EGJOO), and jackhammer esophagus. The gold box contains the interquartile range. The black whiskers mark the 5th and 95th percentiles, and values beyond these upper limits are marked with dots.

Figure 2.

Myotomy lengths in each GERD type. Bar graphs showing differences in total, esophageal, and gastric myotomy lengths in centimeters between those with and without (A) subjective GERD, (B) objective GERD and (C) severe objective GERD. There were no significant differences in total, esophageal, or gastric myotomy lengths for any of the types of GERD (p>0.05 for all comparisons).

Figure 3.

Probability of GERD based on preoperative lower esophageal sphincter (LES) resting pressures. Bar graphs showing the predicted probability of GERD (y-axis) for preoperative LES resting pressures grouped by 10-mmHg ranges (x-axis). (A) LES resting pressure had no impact on subjective GERD. (B) The probability of objective GERD increases in a stepwise fashion with each 10-mmHg decrease in resting pressure (p < 0.0001). (C) The probability of severe objective GERD increases in a stepwise fashion with each 10-mmHg decrease in resting pressure (p < 0.0001).