To the best of our knowledge, this is the first large-scale study analyzing the rate of serious complications and mortality of EGPP after RYGB for recurrent weight gain, suboptimal initial weight loss, dumping syndrome, and GERD. Using the MBSAQIP database, we found the overall rate of complications after EGPP to be relatively low with a mortality of 0%. We also found GERD to be an independent predictive factor of serious complications.

The association between GERD and serious complications is unclear and may be multifactorial. Iatrogenic trauma from the endoscopic procedure and friable gastric tissue seen in reflux and gastritis could contribute [8, 9], although we did not find a significantly higher bleeding rate in this group. It may also reflect that patients with GERD may have had prior endoscopic procedures, thus placing them at higher risk of complications with repeated endoscopy used for EGPP [10]. Finally, this could be due to the greater risk of ulceration in patients with GERD due to the higher acidity in the gastric pouch. Indeed, though RYGB is considered superior to other bariatric surgeries in terms of symptomatic control of GERD, emerging studies have also shown new onset GERD after RYGB [11]. The presence of GERD in this cohort may suggest larger pouch sizes, which have been associated with higher rates of ulcers, potentially due to the persistence of parietal cells in oversized gastric pouches. This could reduce the effectiveness and safety of gastric plication [12, 13]. Marginal ulcers are known risks of bariatric surgery and can lead to severe complications—one study demonstrated a 1.8% incidence of melena secondary to marginal ulceration [14]. It is worth noting that the variable GERD included in the MBSAQIP registry refers to the existence of a pre-operative GERD diagnosis. The methods for assigning these diagnoses lack standardization, making it difficult to ascertain specific details about the diagnostic process. It may include intermittent heartburn symptoms, reduction in symptoms with anti-secretory medications, endoscopic evidence of esophagitis or intestinal metaplasia, radiographic studies demonstrating retrograde flow of contrast, impedance studies showing acid or non-acid reflux among others. Additionally, the database does not capture information about associated hiatal hernias or their repairs, which could be important confounding factors in the relationship between GERD and post-EGPP complications. Gastric bypass reflux may be acidic or non-acidic in nature, an important distinction as these different mechanisms may impact symptom patterns, treatment outcomes, and operative compliactions. More research is needed to investigate the risks and benefits of EGPP in patients with GERD, with particular attention to clearly defined criteria for inclusion.

In our analysis, recurrent weight gain and suboptimal initial weight loss were the primary indications for EGPP. Previous studies have demonstrated EGPP to be effective for treating these. Schroder et al. found that within six months, in patients with significant weight recurrence after RYGB, EGPP led to an average loss of 32% of the weight that had been regained [14]. Jirapinyo and Thompson found that in patients with suboptimal initial weight loss or weight recurrence, EGPP led to 9.5% ± 8.5% total weight loss after 12 months, and 12.5% after 5 years [15]. These studies, as well as others in the literature, demonstrate that EGPP is successful in treating weight recurrence in the long term.

Dumping syndrome (DS) also accounted for a proportion of patients undergoing EGPP (5.5%). DS consists of a cluster of symptoms including nausea, vomiting, and loose stools, induced by the rapid transit of undigested food into the small bowel. Its clinical manifestations are graded by the Sigstad’s score—a score of > 7 suggesting a diagnosis of DS [16]. Dilation of the gastro-jejunal anastomosis (GJA) has been related to DS, along with weight recurrence, after RYGB [17], and therefore, EGPP with narrowing of the GJA is a strategy for symptom mitigation. Tsai et al. reported EGPP to be effective in significantly improving the Sigstad’s score from 13.9 to 8.6 after three months [18]. Pontecorvi et al. reported EGPP to be effective in significantly decreasing symptoms of DS from 15 to 2 by 24 months [17]. It is clear that EGPP is effective for treatment of DS both within the short and long term.

Our study found that EGPP was safe regardless of indication, with a low proportion of adverse events, and no mortalities. This is largely congruent with other studies, which report similar rates of our described complications [7, 14, 19]. Others found similarly low rates of bleeding requiring blood transfusion [20]. Low rates of GJA anastomotic stenosis were also reported in the literature, though our MBSAQIP did not evaluate this specifically. These were typically treated with balloon dilation or lumen-apposing metal stent placement [21,22,23].

There are certain weaknesses to the present study. One of these is the absence of a comparison group. However, outcomes of revisional bariatric surgery have been extensively described in the literature, and it is therefore reasonable to cite those outcomes in the absence of a comparative cohort. This dataset only included variables pre-defined by the MBSAQIP and does not include information such as the timeframe between the index bariatric surgery and the revisional EGPP and how suboptimal initial weight loss or recurrent weight gain were defined. The MBSAQIP search also did not distinguish between the various strategies for EGPP, including the use of argon plasma coagulation and the types of plication devices and techniques, which have been demonstrated in the literature to have varying effects on weight loss and dumping syndrome. Furthermore, we do not have information regarding the factors leading to weight recurrence and suboptimal initial weight loss, which may have incurred selection bias. However, the large sample of cases examined (n = 1474) is helpful in mitigating this weakness and increasing the power of the study. Finally, patients were not excluded based on their procedural or surgical history—it is possible that the complications were found in patients who had a history of repeated endoscopic dilations or other procedures that may have affected the safety or success of EGPP.

Based on our analysis, we propose several key considerations for patient selection and management of EGPP candidates. The procedure appears most appropriate for patients with weight recurrence or suboptimal initial weight loss who are poor surgical revision candidates. However, careful consideration should be given before performing EGPP in patients with GERD, given their doubled risk of complications and readmissions. The procedure is well-suited for the outpatient setting, as evidenced by the 72% same-day discharge rate. Patients should be counseled about the overall risk of serious complications (3.3%), with higher rates (5.1%) in those with GERD. For GERD patients specifically, closer post-procedure monitoring may be warranted.

Future research should focus on several key areas: long-term efficacy data comparing EGPP to surgical revision, standardized criteria for patient selection (particularly regarding GERD status), cost-effectiveness analyses, and quality of life outcomes. Additionally, studies examining technical variations in EGPP techniques and their impact on outcomes would help establish best practices. Multicenter prospective trials would be particularly valuable in addressing these knowledge gaps.