Improving efficacy of the adjustable gastric band: studies of the use of adjuvant approaches in a rodent model.

BACKGROUND: The laparoscopic adjustable gastric band (AGB) has been effective in reducing excess weight by approximately 50% for at least 16 years. However, as with all weight loss approaches, reduction in weight resulting from bariatric surgery is associated with a compensatory reduction in energy expenditure, which may confound and limit weight loss. Adjuvant therapies that reduce food intake and increase energy expenditure may be used to improve weight loss outcomes by ameliorating, or even reversing, this reduction in energy expenditure. METHODS: Rats were either fitted with an AGB or were sham operated and received one of 2 adjunctive pharmacologic treatments, (1) thyroxine or (2) bupropion/naltrexone (Contrave), at a range of doses and matched with vehicle controls (n = 6-8/group) over a 4-week period of combined treatments. Metabolic parameters including food intake, weight, fat mass, and energy expenditure in brown adipose tissue (BAT), whole body calorimetry, and physical activity were assessed. RESULTS: Inflation of the AGB caused a reduction in weight gain that was further enhanced by cotreatment with either thyroxine or Contrave (P<.05). Thyroxine completely ameliorated the reduction in AGB-induced BAT thermogenesis and significantly improved weight loss, particularly in fat mass. Contrave also augmented the loss of weight and fat mass associated with the AGB and increased BAT thermogenesis in banded rats even at doses below that required to change food intake. CONCLUSION: Adjuvant therapies can improve the efficacy of the AGB, at least in part by negating the compensatory reduction in energy expenditure, but also via a combined effect on food intake.

Closed-loop gastric electrical stimulation versus laparoscopic adjustable gastric band for the treatment of obesity: a randomized 12-month multicenter study.

OBJECTIVE: To compare the weight loss, change in quality of life (QOL) and safety of closed-loop gastric electrical stimulation (CLGES) versus adjustable gastric band (LAGB) in the treatment of obesity. METHODS: This multicenter, randomized, non-inferiority trial randomly assigned the patients in a 2:1 ratio to laparoscopic CLGES versus LAGB and followed them for 1 year. We enrolled 210 patients, of whom 50 were withdrawn preoperatively. Among 160 remaining patients (mean age=39±11 years; 75% women; mean body mass index=43±6 kg m-2) 106 received CLGES and 54 received LAGB. The first primary end point was non-inferiority of CLGES versus LAGB, ascertained by the proportion of patients who, at 1 year, fulfilled: (a) a ⩾20% excess weight loss (EWL); (b) no major device- or procedure-related adverse event (AE); and (c) no major, adverse change in QOL. Furthermore, ⩾50% of patients had to reach ⩾25% EWL. The incidence and seriousness of all AE were analyzed and compared using Mann-Whitney's U-test. RESULTS: At 1 year, the proportions of patients who reached all components of the primary study end point were 66.7 and 73.0% for the LAGB and CLGES group, respectively, with a difference of -6.3% and an upper 95% CI of 7.2%, less than the predetermined 10% margin for confirming the non-inferiority of CLGES. The second primary end point was also met, as 61.3% of patients in the CLGES group reached ⩾25% EWL (lower 95% CI=52.0%; P<0.01). QOL improved significantly and similarly in both groups. AE were significantly fewer and less severe in the CLGES than in the LAGB group (P<0.001). CONCLUSIONS AND RELEVANCE: This randomized study confirmed the non-inferiority of CLGES compared with LAGB based on the predetermined composite end point. CLGES was associated with significantly fewer major AE.

Intragastric stimulation is ineffective after failed adjustable gastric banding.

BACKGROUND: Gastric pacing has gained popularity as an effective and safe minimally invasive procedure to treat morbid obesity. This study evaluates the outcome of gastric pacing as a bariatric re-do procedure in patients who developed failure after adjustable gastric banding (AGB) due to band migration. METHODS: 8 patients were enrolled in this analysis. After implantation of an AGB, they had developed band failure due to band migration. The implantable gastric stimulator (IGS) was implanted laparoscopically as a second-line operation after gastroscopic removal of the band. RESULTS: Median time (range) from AGB complication to implantation of the IGS was 42 (10.3-50.3) months. During that time, all 8 patients had regained significant weight. All IGS devices could be implanted laparoscopically, without intra- or perioperative complications. The minimal body weight following IGS implantation was reached after 5 (0-12) months. The median observation time was 23 (11.3-27.5) months. 1 year after IGS implantation (n=7), median weight was 116 (98-165) kg, equivalent to a median BMI of 41.1 (36.055.8) kg/m(2), which is not statistically different to preoperative values and therefore prompted us to stop our ongoing trial. In all but 2 patients, the IGS device was explanted. During the same procedure, patients underwent a gastric sleeve resection (n=4) or a Roux-en-Y gastric bypass (n=2). CONCLUSION: The implantation of an IGS was an ineffective second-line operation after AGB migration.

The Stretta procedure: device, technique, and pre-clinical study data.

The initial concept of delivering RF energy to the gastroesophageal junction for the treatment of GERD was based on the well-established safety profile and scientific clinical evidence supporting the effectiveness of this technology in other disease states. As described in this article, the Stretta procedure is an endoluminal procedure inducing collagen tissue contraction, remodeling, and modulation of the triggering threshold for transient LES relaxations. The preclinical experience with this device included feasibility studies to determine optimal treatment parameters and device design. This was followed by longitudinal animal studies to elucidate the mechanism of safety and effect of this intervention as it relates to LES physiology and histopathology. In these studies, RF elevated the LES pressure and gastric yield pressure in a porcine model of botulinum toxin induced LES hypotension. The elevation in GYP more than 6 months was confirmed in a subsequent evaluation. Thickening of the LES after RF delivery has been demonstrated using histopathological evaluation and EUS. Additionally, using a canine model of triggered transient LES relaxations (tLESR), RF significantly reduced the frequency of tLESRs and reflux events. Additional evaluation was performed in human subjects undergoing esophagectomy, confirming feasibility and Histopathologic results of the treatment. Subsequent clinical trials confirm the safety and mechanism of action data of these pre-clinical studies and are presented in this publication.