Alternative Minimally Invasive Options: Endoluminal Bariatric Procedures

Fig. 1.

The TransOral GAstroplasty (TOGA) system (Satiety Inc, Palo Alto, CA) has been studied for endoscopic gastroplasty. The device is a flexible stapler capable of performing full-thickness tissue apposition. Vacuum is used to appose the gastric walls, and a partition is created parallel to the lesser curvature (Fig. 2). The device must be removed for reloading. Deviere et al. reported TOGA in 21 patients with BMI of 43.3 kg/m² [8]. No serious adverse events were noted, although vomiting, pain, nausea, and transient dysphagia were reported. All patients had partially or fully intact stapled sleeves at 6 months, although gaps were noted in 13 patients. Average weight loss was 12 kg after 6 months, or 24.4 % of EWL. Moreno et al. reported successful TOGA in 11 patients using a second-generation device and re-treatment to create additional distal restrictions if necessary [9]. No serious adverse events were reported. Average weight loss was 17.5 kg at 3 months and 24.0 kg at 6 months. Mean BMI decreased from 41.6 to 33.1 kg/m² after 6 months. A multicenter study including 67 patients (53 were available for follow-up) reported EWL of 52.2 % in patients with BMI ≥ 40 and 41.3 % in BMI < 40 [10]. Hemoglobin A1c decreased significantly, from 7.0 to 5.7 %; there were also significant improvements in triglyceride levels and HDL. One case of respiratory insufficiency and another of asymptomatic pneumoperitoneum were noted.

Fig. 2.

The TransOral GAstroplasty (TOGA) system was used to create a vertical stapled gastroplasty along the lesser curvature of the stomach. The anterior and posterior walls of the stomach were drawn into the suction chamber and stapled together (Courtesy of Ethicon, Cincinnati, OH, with permission).

The TERIS, or Trans-Oral Endoscopic Restrictive Implant System (BaroSense, Menlo Park, CA), is an implanted diaphragm containing a 10 mm orifice (Fig. 3). The device is stapled into the gastric cardia. De Jong et al. studied 13 patients and reported 12 successful placements [11]. One patient was unsuccessful due to gastric perforation. Two patients developed pneumoperitoneum. After these events, technical adjustments were made to the procedure, and no further complications were seen. Average procedure time was 142 min. Median BMI decreased from 42.1 to 37.9 kg/m² after 3 months. Weight loss of 16.9 kg, and EWL of 22.2 %, was reported at 3 months.

Fig. 3.

The TERIS, or Trans-Oral Endoscopic Restrictive Implant System (BaroSense, Menlo Park, CA, with permission), places a restrictive device across the gastric cardia.

Space-Occupying Devices

Space-occupying devices offer a noninvasive option for weight loss. These include balloons and polymers. Space-occupying devices result in volume displacement and gastric distention (Fig. 4). Additionally, changes in gastric motility and hormones have been noted. Notably, cholecystokinin may be released due to gastric distention, inducing pyloric constriction and delayed gastric emptying. The first intragastric balloon was approved for use in the United States in 1985, inspired by the observation that patients with bezoars lost weight. The technology has not seen widespread adoption in the United States over the past three decades. Devices in use to date, primarily in Europe, have been utilized as a bridge to definitive therapy.

Fig. 4.

Intragastric balloon.

The BioEnterics Intragastric Balloon, or BIB (Allergan, Irvine, CA), is a silicone elastomer balloon that can be implanted into the stomach endoscopically [12]. It can be filled with saline and methylene blue dye, which leaks and changes the color of urine if the balloon’s integrity is compromised. The balloon is resistant to gastric acid for approximately 6 months.

The BIB has been studied in a large number of patients compared to other endoscopic bariatric therapies. A meta-analysis of 3,698 patients reported weight loss of 14.7 kg and 32.1 % EWL after 6 months [13]. BMI decreased by 5.7 kg/m². Complications included nausea, vomiting, bowel obstruction (0.8 %), and gastric perforation (0.1 %). 4.2 % of patients had early removal. A retrospective study of 2,515 patients with mean BMI of 44.4 kg/m² reported that BIB placement resulted in two mortalities in patients with previous gastric surgery. After 6 months, there was decrease in BMI by 9.0 kg/m² [14]. There was significant improvement in blood pressure and lipid profile, and fasting glucose. Of 488 diabetics, 87.2 % had significant decrease or normalization in hemoglobin A1c.

A prospective study of the metabolic changes after BIB placement included 130 patients with BMI of 43.1 kg/m² [15]. Ten patients required early balloon removal, 6 of which were due to intolerance, abdominal pain, or vomiting. During the 6-month follow-up period, patients were kept on 1,000–1,200 kcal per day. Weight loss after 6 months was 13.1 kg, resulting in decrease of class IV obesity from 23 to 8 % in the cohort. Statistically significant metabolic improvements were noted, with decrease in prevalence of hyperglycemia from 50 to 12 %. Hypertriglyceridemia decreased from 58 to 19 %. Prevalence of severe hepatic steatosis decreased from 52 to 4 % in patients who had BMI decrease greater than 3.5 kg/m². Follow-up after balloon removal, for a median 22 months, found that 50 % of patients regained some weight.

The importance of dietitian counseling after balloon placement was studied by Tai et al. [16]. Twenty-eight patients with mean BMI of 32.4 ± 3.7 kg/m² had BIB placement for 6 months, with decrease in BMI to 28.5 ± 3.7 kg/m² at removal. Dietitian follow-up was scheduled at every week for 2 weeks, every 2 weeks for 1 month, and then monthly. Good adherence was defined as appearance for 50 % of scheduled visits. Responders were those who had at least 20 % EWL. Twenty patients were responders and 8 were nonresponders. Of the responders, 85 % had good adherence versus 25 % of nonresponders.

A prospective single-blinded study examined histologic improvement in nonalcoholic steatohepatitis [17]. Patients were randomized to BIB placement (11 patients) or sham endoscopy with gastric instillation of 500 mL of saline (10 patients). All patients were placed on the American Heart Association diet. Three BIB patients had removal due to epigastric discomfort and vomiting. BMI decreased by 1.6 kg/m² in the BIB group versus 0.8 kg/m² in the control group. At the end of treatment, NAFLD activity score was significantly lower in the BIB group (2 versus 4), and there was a trend towards improvement in median steatosis score in the BIB group. There was no change in median lobular inflammation, hepatocellular ballooning, or fibrosis. ALT and AST were not significantly changed in either group.

The effects of balloon placement on depression were studied by Deliopoulou et al. [18]. One hundred consecutive females were classified into depressed (65 patients) and non-depressed (35 patients) groups based on Beck Depression Inventory score. The groups were otherwise similar. Weight loss of 39.3 % EWL in the depressed group was similar to weight loss of 36.1 % EWL in the non-depressed group. The depressed group had decrease in depression score from 20.3 ± 8.5 to 7.9 ± 5.6 at the time of balloon removal. Additionally, 70.8 % of the patients had resolution of depression; the rate of severe depression declined from 27.7 to 1.5 %.

Repeat BIB insertion was studied prospectively by Dumonceau et al. [19]. Of 118 patients, 8 had immediate balloon reinsertion, 11 had placement after a balloon-free interval, and 99 had no balloon replacement. Patients with second balloon after a balloon-free interval regained an average 13.6 kg during that interval. The second balloon placement resulted in significantly less weight loss (9.0 kg versus 14.6 kg) and less EWL (18.2 % versus 49.3 %). The complication rate, including esophagitis and intolerance, was higher with the second balloon (26 % versus 11 %), although this was not significant. There was no difference in weight loss with second balloon placement by the third year of follow-up. Second balloon placement had no effect on the proportion of patients having ≥ 10 % weight loss or bariatric surgery during the 4.9-year follow-up period. Another study reported 112 patients with second balloon placement within 1 month of removing the first balloon [20]. Mean BMI loss was 6.5 kg/m² with the first balloon, versus 2.5 kg/m² with the second balloon.

Kotzampassi et al. studied long-term weight trends after BIB removal in 500 patients with initial BMI of 43.7 kg/m² [21]. At the time of BIB removal, 83 % of patients were classified as successful, with EWL of at least 20 %. This group had mean weight loss of 23.9 ± 9.1 kg and BMI loss of 8.3 kg/m². At 5-year follow-up, including 41 % of the original cohort, mean weight loss was 7.3 ± 5.4 kg and BMI loss was 2.5 kg/m². Twenty-three percent of patients maintained weight loss of at least 20 % of EWL.

BIB has been studied as a bridge to RYGB in super-superobese patients [22]. Sixty consecutive patients with mean BMI of 66.5 ± 3.4 kg/m² had either BIB placement (23 patients) or no BIB (37 patients). BIB was left in place for 155 ± 62 days with BMI loss of 5.5 ± 1.3 kg/m². The BIB group experienced significant decrease in systolic blood pressure and gamma-glutamyl transpeptidase. Operative time for RYGB was significantly shorter in the BIB group (146 ± 47 versus 201 ± 81 min). There were significantly fewer major adverse events, classified as conversion to laparotomy, ICU stay over 2 days, and hospital stay over 2 weeks, in the BIB group (2 versus 13). Weight loss was similar in both groups 1 year after RYGB.

BIB, filled with 500 mL saline, has been compared with Heliosphere BAG, which is filled with 950 mL of air [23]. Thirty patients with mean BMI of 46.3 kg/m² were randomized to each group. Decrease in BMI was 5.7 kg/m² in the BIB group versus 4.2 kg/m² in the Heliosphere group. Patients in the Heliosphere group did experience significantly longer extraction time and significantly more extraction discomfort during passage through the cardia and lower pharynx. A nonrandomized study by Caglar et al. compared the BIB with Heliosphere BAG [24]. Thirty-two patients nonresponsive to 6 months of medical and diet therapy had BIB placement (19 patients, BMI 45.6 ± 9 kg/m²) or Heliosphere BAG placement (13 patients, BMI 45.0 ± 8 kg/m²). After 6 months, weight loss was significantly higher in the BIB group (19.0 kg versus 13.0 kg), as was EWL (38.3 % versus 21.9 %). One patient in the BIB group had early removal due to persistent nausea and vomiting at 1 month. One patient in the BIB group died 13 days after placement due to cardiac arrest related to aspiration of gastric contents.

The silicone TransPyloric Shuttle (BAROnova, Goleta, CA) comprises a large spherical bulb connected to a smaller cylindrical bulb by a flexible tether. The sphere is too large to traverse the pylorus, while the cylinder can pass into the duodenal bulb during peristalsis. The device intermittently blocks the pylorus, reducing gastric emptying rate. The device is delivered via transoral catheter and is removed endoscopically. A prospective single-center open-label study of 20 patients with mean BMI of 36.0 kg/m² reported weight loss of 8.9 ± 5.2 kg and EWL of 31.3 ± 15.7 % after 3 months [24]. Mean weight loss was 14.6 ± 5.7 kg and 50.0 ± 26.4 % EWL after 6 months. Persistent gastric ulcer required early removal in two patients.

The Duo balloon (ReShape, San Clemente, CA) comprises two silicone spheres filled with 900 mL of saline. Deflation of one balloon alone will not result in migration. According to company data, patients have experienced loss of one-third of excess weight after 6 months. A 3-center prospective trial included balloon placements in 21 patients and 9 control patients [25]. Both groups had similar diet and exercise counseling. In the balloon group, 4 patients required readmission for nausea. Two had gastritis at balloon removal. At 48 weeks, 30 % of the balloon group reached the 25 % EWL target versus 25 % of the control group.

The SatiSphere (EndoSphere, Columbus, OH) is a preformed memory wire that self-anchors in the distal stomach and duodenum by conforming to the shape of the duodenum. The device slows the travel of food through the duodenum, altering satiety hormones and glucose metabolism. An early trial reported that all patients lost weight, with average EWL of 12 % over the first month. Another trial of 31 patients with mean BMI 41.3 kg/m² compared 10 controls with 21 implanted patients. Device migration occurred in 10 of 21 implanted patients, requiring emergency surgery in two patients. Weight loss was 6.7 kg after 3 months in patients completing the trial versus 2.2 kg in controls. The device was found to delay glucose absorption and insulin secretion and to alter GLP-1 kinetics [26].

Malabsorptive Procedures

Small intestinal bypass is a key component of many bariatric surgical procedures. It is postulated to play an especially important role in the improvement of metabolic parameters after bariatric surgery. Endoluminal devices have been developed to bypass absorption of nutrients in the small intestine.

The EndoBarrier duodenal-jejunal bypass liner, or DJBL (GI Dynamics, Lexington, Mass), is a self-expanding nickel-titanium implant attached to a 60 cm tubular polymer sleeve that extends from the duodenal bulb into the jejunum (Fig. 5). It prevents food from contacting the mucosa of the small intestine, but allows biliary and pancreatic secretions to travel along the outside of the sleeve to the jejunum. A multicenter randomized trial of 41 patients assigned 30 patients with BMI 48.9 kg/m² to DJBL placement and 11 patients with BMI 47.4 kg/m² to diet control [27]. Four patients required device removal due to migration, obstruction, pain, and dislocation of the anchor. There were no serious adverse events. After 3 months, BMI decrease was significantly higher in the DJBL group: 5.5 kg/m² versus 1.9 kg/m² in the control group. Of 8 diabetics with DJBL placement, 7 had improvement in diabetes. Gersin et al. reported an open-label randomized multicenter trial including 25 patients, with successful implantation in 21 patients [28]. Implantation was not successful in patients with a small duodenal bulb. Seven patients required device removal due to adverse events, 3 of which were bleeding presenting as hematemesis. Weight loss after 3 months was significantly higher in the DJBL group: 8.2 ± 1.3 kg versus 2.0 ± 1.1 kg in the sham group. Another randomized trial by Tarnoff et al. included 25 patients implanted with DJBL and 14 control patients [29]. All patients received baseline dietary and lifestyle counseling. After 12 weeks, EWL was 22 % for the device group versus 5 % for the control group. There was an adverse event rate of 20 %, including bleeding, migration, and obstruction.

Fig. 5.

The EndoBarrier duodenal-jejunal bypass liner, or DJBL (GI Dynamics, Lexington, Mass, with permission), is anchored in the duodenal bulb and extends 60 cm into the duodenum.

A modified version of the DJBL with a restrictive (4 mm) proximal opening was studied by Escalona et al. in ten patients with average BMI of 40.8 kg/m² [30]. Weight loss after 3 months was 16.7 ± 1.4 kg. Eight patients required balloon dilation of the restrictive orifice after developing abdominal pain, nausea, and vomiting. Gastric emptying was delayed in 84 % of patients at 3 months but generally improved after the device was removed.

Escalona et al. studied 1-year outcomes after DJBL implantation in an open-label prospective trial [30]. Thirty-nine patients with BMI 43.7 ± 5.9 kg/m² had implantation of the device; 3 patients could not be implanted due to short duodenal bulb. There were 15 early removals, due to anchor movement (8), device obstruction (3), abdominal pain (2), acute cholecystitis (1), and patient request (1). In the 24 patients with the device in place for 1 year, average weight loss was 22.1 ± 2.1 kg, BMI loss was 9.1 ± 0.9 kg/m², and EWL was 47.0 ± 4.4 %. Decrease in waist circumference from 120.5 ± 6.8 to 96.0 ± 2.6 cm was significant. Statistically significant decreases were also seen in blood pressure, hemoglobin A1c, total cholesterol, LDL, triglycerides, and in the prevalence of metabolic syndrome (83.3–41.6 % of patients).

Rodriguez et al. randomly assigned patients with type II diabetes and mean BMI of 38.9 kg/m² to DJBL or sham endoscopy [31]. After 6 months, hemoglobin A1c fell by 2.4 ± 0.7 % in the DJBL patients, versus a fall of 0.8 ± 0.4 % in the sham arm. The result did not reach significance.

Weight Regain

Bariatric Surgery

Roux-en-Y gastric bypass (RYGB), sleeve gastrectomy, adjustable gastric band, vertical banded gastroplasty, duodenal switch, and biliopancreatic diversion are the most common bariatric surgeries encountered by physicians treating weight regain [32].

Of these, RYGB is the most prevalent [33]. Additionally, RYGB can be revised endoscopically. RYGB typically results in EWL of 56.7–66.5 % over 24 months after surgery; additionally, there is commonly improvement in or resolution of diabetes in 84 %, hypertension in 68 %, obstructive sleep apnea in 81 %, and improvement in hyperlipidemia in 97 % [32–36]. The mechanisms by which RYGB induces weight loss and improvements in comorbidities are not entirely understood, but restriction induced by small gastric pouch size and stoma aperture likely results in reduced caloric intake. Bypass of portions of the gastrointestinal tract likely results in decreased calorie absorption [37].

Patients typically experience rapid weight loss for 12–18 months after RYGB and then reach a stable weight as energy intake and expenditure reach equilibrium [37, 38]. Approximately 20 % of patients fail to achieve >50 % EWL within 1 year of surgery. Additionally, 30 % of patients have had weight regain at 18–24 months postoperatively; weight regain of a mean 18 kg at 2 years has been reported [39, 40]. Another study reported weight regain in 63.6 % within 48 months [41]. The superobese (BMI > 50 kg/m²) fail to achieve BMI < 35 kg/m² in 60 % of cases [42, 43]. Weight regain can result in recurrence of comorbidities, decreased quality of life, and adverse effects on mental health.

The mechanisms of weight regain after RYGB are likely multifactorial. Long-term outcomes after RYGB are influenced by preoperative BMI and postoperative dietary adherence [44]. Neuroendocrine-metabolic dysregulation may result in a starvation response, increasing appetite and decreasing metabolic rate [45, 46]. Decreased satiety may also be secondary to loss of restriction; larger pouch size and larger diameter of the gastrojejunal anastomosis (GJA) correlate with increased postoperative weight regain [47–50]. Loss of malabsorptive bypass may be an issue if there is a gastrogastric fistula [51].

Treatment of Weight Regain

There are multiple surgical procedures to address weight regain after RYGB, including reconstruction of the gastrojejunal anastomosis, placement of adjustable gastric band over the gastric pouch, revision of the pouch, and distal gastric bypass [50]. However, none is ideal, and surgical revision is relatively uncommon compared to the number of patients with weight regain [52]. Patients requiring surgical revision are older [53]. Complication rates are high, with patients experiencing greater intraoperative blood loss and longer procedure times [53–55]. Mortality rates are over twice as high as that of the primary surgery [52]. The cost may not be covered by insurance [56].

Less invasive endoluminal revisions that reduce gastric pouches’ size and GJA diameter may have a more favorable risk profile in this population, as well as lower cost. Many techniques have been studied; of these, sclerotherapy, endoluminal suturing, and tissue plication will be discussed.

Sclerotherapy

Endoscopic injection of sclerosant, such as sodium morrhuate, around the GJA can be used to reduce GJA aperture and tissue compliance. Endoscopic sclerotherapy can be performed under conscious sedation. The procedure begins with injection of a test dose at the rim of the GJA, followed by monitoring for adverse reactions. The sclerosant is then injected into the submucosa around the circumference of the GJA until a bleb forms. Overinjection can result in bleeding; this is preceded by dark red or black discoloration. Aliquots are usually 2 mL, and the total injection is usually 10–25 mL [57]. Intravenous ciprofloxacin is usually given before the procedure and a 5-day course of liquid ciprofloxacin or trimethoprim-sulfamethoxazole should be provided. The patient should be nil per os for a day after the procedure and advance from liquid to regular diet over the following 4 weeks. Repeat sclerotherapy sessions are scheduled every 3–6 months with a goal GJA diameter of 12 mm; most patients require two or three sessions [58]. GJA measurements should be performed at the beginning of the next sclerotherapy session as the diameter immediately after injection is transiently obscured by edema [57]. Injection may be difficult during repeat procedures as tissue sclerosis can make bleb formation challenging.

Only gold members can continue reading. Log In or Register to continue