RFA of gastric remnant pouch helps treat weight regain after gastric bypass

Last Updated: 2017-07-25

By Will Boggs MD

NEW YORK (Reuters Health) - Radiofrequency ablation of the gastric remnant pouch contributes to weight loss in patients who regain weight after Roux-en-Y gastric bypass (RYGB) surgery, according to results from a 25-patient study.

"After each radiofrequency ablation (RFA) treatment, patients would lose weight and then their weight would plateau," Dr. Julian A. Abrams from Columbia University Medical Center, New York told Reuters Health by email. "With each subsequent treatment, the plateaus tended to be lower than the previous weight plateaus. This suggests that RFA has significant potential to induce weight loss in this patient population and that further refinements to dosimetry and treatment intervals could result in even greater weight loss."

About 70% of patients who undergo RYGB surgery lose weight, but up to a quarter of these patients have significant weight regain, and their treatment options are limited.

Dr. Abrams and colleagues from four centers investigated the feasibility, safety, and efficacy of RFA of the gastric remnant pouch and gastrojejunal anastomosis in their open-label, single-arm study of patients with significant weight regain after RYGB.

Among the 22 patients who completed 12 months of follow-up, 18 received three RFA treatments and four were treated twice, according to the July 13 Gastrointestinal Endoscopy online report.

The entire surface area of the gastric remnant pouch was successfully ablated in 59 of the 65 RFA treatments, with no serious adverse events during the endoscopies and only minor mucosal tears with self-limited bleeding in 38 procedures (58.5%).

The median excess body weight loss at 12 months was 18.4% (31.0 pounds), and significant weight loss was observed as early as 3.5 months (median, 11.4%) and 7.5 months (median, 10.0%) after the procedures.

Four patients gained up to 5 pounds during the 12 months after the procedure.

The authors note that there was no comparator arm in the study and that participating patients may have been highly motivated to lose weight and may have made other behavioral changes in diet and exercise routines that contributed to their weight loss.

"The mechanisms underlying the observed weight loss are unclear," Dr. Abrams said. "RFA may decrease compliance of the gastric remnant pouch and increase a sensation of fullness when eating. Or RFA may have neurohormonal effects that contribute to weight loss. A better understanding of the mechanisms will be important to optimize RFA therapy in this patient population."

"Unfortunately," he said, "there are few good treatment options for patients with weight regain after RYGB. Currently, all endoscopic treatments for this patient population are experimental."

"Based on this trial, it appears that RFA may represent an effective therapy for weight loss with an acceptable safety profile," Dr. Abrams concluded. "However, further studies are needed in carefully selected populations to better define the role of RFA in the treatment paradigm."

Dr. Almantas Maleckas from Lithuanian University of Health Sciences in Kaunas, a visiting professor at University of Gothenburg, Sweden, who recently reviewed the etiology and treatment options of weight regain after RYGB, told Reuters Health by email, "The idea to use RFA for such a purpose as treatment of weight regain after RYGB is novel and very interesting. The reason why it is interesting is that it could be applied endoscopically and the mean procedure time was slightly more than 20 min. In comparison, other endoscopic procedures that intend to reduce gastric pouch or stoma after RYGB take much longer time, are more complicated, and need advanced skills."

"RFA potentially could be as an initial procedure, followed by more complex surgical procedures if RFA fails," he said. "However, we need to know at least medium-term results (3-5 years) of postprocedural weight loss before one can define the role of RFA in the treatment of weight regain after RYGB. If most of RFA patients will fail and will need surgical intervention, aggregated costs could be higher."

"Weight regain after RYGB is a complex problem," Dr. Maleckas said. "The main factors that lead to weight regain could be surgical (dilatation of pouch/stoma), lifestyle and mental health, or hormonal/metabolic imbalance. Sometimes even combinations of these factors."

"Investigation and treatment of such patients should be done at specialized centers where multidisciplinary teams could evaluate the patient and chose the most appropriate treatment method or combination of different interventions," he concluded. "RFA addresses only one factor - dilatation of pouch/stoma - and the results could be disappointing if other factors will not be addressed in the treatment."

Medtronic funded the study, employed one of the five authors, and provided research support for the other four authors. The Barrx RFA catheters used in the study are not FDA-cleared for weight loss treatment.

SOURCE: http://bit.ly/2vGipXQ

Gastrointestinal Endoscopy 2017.