DISCUSSION
The GJA review by APC is known to be a relatively safe and effective strategy to manage weight recovery after RYGB. Bleeding at the anastomotic site is an uncommon complication associated with this therapy. Another possible complication is the stenosis of the anastomosis. Endoscopic treatment is the first-line therapy for both situations [13].
In the present study, the endoscopic APC has used with the objective of reducing the diameter of GJA and, therefore, promoting weight loss after RYGB that was relapsed. The results obtained were similar to the literature. Figures 2 and 3 show the results of weight loss in both groups, with the average weight reduction in the APC group being 15.02 ± 9.63 in relation to the Sham control group after 6 months. Thus, the present study confirms the literary findings, showing that this reduction in weight that has relapsed after RYGB is closely related to the reduction of the anastomotic diameter from 34.25 ± 6.13 mm (initial) to 12.65 ± 2.11 mm (final), with a reduction of 21.60 ± 3.19 mm, considering that the liquid diet and nutritional counselling were applied in both groups.
Another important fact that the present study confirmed has in relation to the safety and efficacy of the APC outlet reduction procedure, given that there has only one complication due to stenosis after the first session of the APC, not requiring treatment. In addition, the technique has 100% successful.
According to the results of the present study, authors studied 30 patients undergoing treatment with an argon plasma, after gastric bypass, and observed after 3 endoscopic sessions of APC spaced between each other by 8 weeks, with an average weight loss of 15.0 kg. In addition, a prospective controlled longitudinal study with APC showed a success rate of 90.0% for weight loss using APC and a reduction of up to 41.0% in the relapsed weight.[19] Another study retrospective with 37 participants, the use of APC had a success rate of 50.0% for weight loss using APC and a 24.0% reduction in relapsed weight.[21]
Further, a study analyzed APC with a 3 and 6-month follow-up as anastomotic reduction therapy after RYGB and showed that in 53 patients (age 49.0 ± 1.3 years, BMI mean was 52.1 ± 10.7 kg m-2. The postoperative period, BMI mean was 29.6 ± 1.1 kg m-2. The argon plasma has performed 8.6 ± 3.4 years after RYGB, with weight recovery resulting in a BMI of 35.4 ± 1.1 kg m-2. The reduction in anastomosis was 16.1 ± 3.7 mm to 13.5. The average number of sessions was 1.3.[24] An anastomotic diameter size over 15.0 mm in the weight regain scenario may be subject to endoscopic review.[18,32,33]
Also, authors published retrospective analysis data obtained from 558 patient records with regained weight in eight bariatric centers in the USA and Brazil, who underwent APC between July 31, 2009, and March 29, 2017. The mean weight was 94.5 ± 18.6 kg and the mean BMI was 34.0 kg/m2 in the APC. When data were available, the mean of the lowest weight was 67.0 ± 23.0 kg and the mean of the lowest BMI was 24.1 kg/m2 after RYGB. The average weight loss was 6.5, 7.7 and 8.3 kg at 6, 12, and 24 months, respectively, and the changes in weight over time were statistically significant.[11]
Besides, authors evaluated the efficacy and safety of endoscopic treatment of increased GJA with APC. A randomized controlled study was performed comparing APC to exclusive multidisciplinary management after regaining weight. Forty-two patients were divided into two groups: APC (n=22) and control (n=20). After 14 months of follow-up with a crossover in 6 months, significant improvement in satiety and greater weight loss has found in the APC group and after crossing. APC has associated with significant weight loss 9.73 vs. + 1.38), reduction in anastomosis diameter, early satiety (0.77 vs. 0.59), p<0.001, and increased quality of life. Considering the average total weight loss during the entire follow-up, weight loss was similar in both groups (13.02 kg in the APC and 11.52 kg in the control).[12]
Also, another study published in 2020[14], reported ablation with argon plasma coagulation (APC) plus full-thickness endoscopic suture (FTS-APC) and ablation alone for the treatment of weight recovery. A randomized, single-pilot study with forty patients, comparing the efficacy and safety of APC alone versus FTS-APC for transoral outlet reduction. Patients weighing at least 20% recover from the nadir and GJA ≥ 15 mm were considered eligible. The primary endpoint was the percentage of total weight loss (% TWL) in 12 months. Secondary outcomes were the incidence of adverse events, improvement in laboratory metabolic parameters and improvement in the quality of life, and eating behavior. At 12 months, the mean %TWL was 8.3% ± 5.5% in the APC group alone versus 7.5% ± 7.7% in the STF-APC group. The percentage of solid pre-revision gastric retention in 1 hour was positively correlated with the probability of reaching ≥10% TWL in 12 months. Both groups experienced significant reductions in levels of low-density lipoprotein and triglycerides at 12 months.
A recent retrospective study of two hundred and seventeen patients compared the effectiveness of different APC configurations in the treatment of weight recovery. Patients who received low-dose (45-55 W) and high-dose (70-80 W) APC were compared. Of the selected patients, 116 (53.5%) patients underwent low-dose APC sessions (2.4 sessions/patient) and 101 (46.5%) patients underwent 144 APC sessions. in high doses (1.4 ± 0.7 sessions / patient). Follow-up rates were 82.9% and 75.3% at 6 and 12 months. At 6 months, the low and high dose groups showed 7.3% and 8.1% TWL, respectively. At 12 months, the low and high dose groups experienced 5.1% and 9.7% TWL, respectively. Technical success was 100%. The overall rate of AE was 8.0%, with stenosis being 4.6%. Therefore, the higher watt APC has associated with greater weight loss.[15]
In this context, the authors Heneghan et al. (2012)[25] concluded that patients with normal post-surgical anatomy regain less weight than patients with altered proximal surgical anatomy, especially in the increase in the diameter of the gastrojejunal anastomosis. In addition, the authors Abu et al[26] and Ramos et al. (2017)[27] evaluated the size of GJA and its influence on weight loss, where an anastomosis calibrated to 15.0 mm shows better results when compared to the anastomosis of 45.0 mm in a 2-year follow-up. Therefore, values ​​between 10 and 15.0 mm are the desired GJA diameter.
Thus, several methods such as endoluminal reduction of GJA such as surgery[28], suturing[29,30], and APC in gastrojejunal anastomosis have been proposed to reduce the recovered weight in patients undergoing RYGB.[12] In this scenario, surgical treatments are the most performed, however, they are associated with a higher incidence of complications and morbidity and mortality when compared to the other treatments proposed above.[28]
Besides, transoral outlet reduction (TORe) performed using a traditional suture pattern is effective in inducing short and medium-term weight loss in patients with weight recovery after RYGB.[30] In this sense, a study analyzed the technical feasibility and safety of TORe in stock markets were determined and its impact on weight and metabolic profiles has assessed. Patients with RYGB who underwent pouch TORe were included. The GJA has ablated by coagulation with argon plasma or dissected by endoscopic submucosal dissection. A suture has used to place stitches around the GJA in a continuous ring. The suture has attached to a balloon (8-12 mm). The primary endpoint was technical feasibility. Secondary outcomes were the percentage of total body weight lost (% TWL), adverse events, impact on comorbidities, and predictors of weight loss. Thus, 252 patients with RYGB were submitted to 260 TORe. They recovered 52.6 ± 46.4% of the weight lost and weighed 107.6 ± 24.6 kg. The technical success rate was 100%. At 6 and 12 months, the% TWL was 9.6 ± 6.3 and 8.4 ± 8.2. At 12 months, blood pressure, hemoglobin A1c and ALT had improved.[31]
A systematic review and meta-analysis study evaluated the effectiveness of endoscopic therapies for recovered weight after RYGB. The primary endpoints were absolute weight loss (AWL), excess weight loss (EWL), and total body weight loss (TBWL). Thirty-two studies were included in the qualitative analysis. Twenty-six full-thickness (FT) endoscopic sutures described and AWL, EWL, and TBWL combined in 3 months were 8.5 kg, 21.6 kg and 7.3 kg, respectively. At 6 months, they were 8.6 kg, 23.7 kg and 8.0 kg, respectively. At 12 months, they were 7.63 kg, 16.9 kg and 6.6 kg, respectively. Subgroup analysis showed that all results were significantly greater in the group with suture with TF combined with APC. Two articles described APC alone with an average AWL of 15.4 ± 2.0 and 15.4 ± 9.1 kg at 3 and 6 months, respectively. When performing APC before the suture, it seems to result in greater weight loss.[32]
Since the loss of gastric restriction in the bypass can be one of the main causes of obesity recurrence. Therefore, the present study showed that the use of argon plasma in reducing the gastrojejunal anastomosis diameter promoted greater weight loss compared to the control group that underwent only to upper digestive endoscopy with sedation and liquid diet.