Development and Testing of an Attachable Gastric Cuff and Small Intestinal Exclusion Sleeve As a New Flexible Endoscopic Method for Treatment of Obesity

Abstract

Background: The potential for flexible endoscopic treatments for morbid obesity are attractive since current laparoscopic surgical treatments are expensive ($25,000-40,000), and carry a substantial morbidity and significant mortality rate. More effective surgical procedures combine gastric restrictive and malabsorptive components. There has been a high failure rate for flexible endoscopic attachment methods in the obesity field. Devices and Methods: A soft flexible lightweight, non-restrictive cuff was designed for attachment to gastric tissue close to the cardio-esophageal junction (CEJ). This allowed free expansion or closure of the tissue at or below the CEJ. A new attachment method using load-spreading curved sprung bolsters placed through a hollow needle on the serosal surface was developed and tested surgically and then endoscopically. The cuff is proposed to serve as a connection to a gastro-jejunal food exclusion tube. This device is designed to restrict food intake and also to bypass a proportion of the GI tract by keeping the nutrients out of contact with the proximal jejunum. Gastric and small intestinal peristalsis moves the food in the pliable exclusion tube through stomach, duodenum and proximal jejunum. Results: In 9 pigs (99-122Kg), successful cuff attachment was achieved at in all animals (at 2 weeks in 2 animals and then at 5 weeks in 7 animals) but sometimes with 1 or more of 12 attachment points failing. The cuffs did not fall out in these experiments. Successful cuff attachment evolved through trial and error in initial experiments: More rigid cuffs all lost functional attachment within 10 days, but never completely detached. The feasibility of endoscopic method of delivery and attachment was demonstrated. The cuff could be removed with complete healing of the CEJ at repeat endoscopy at 7 days. Histology showed fibrosis around most tissue anchors suggesting secure attachment. In a smaller number of animals the food exclusion tube was attached to the cuff. Pathology evaluation of the duodenum and jejunum showed some villous congestion but little inflammatory response. Pigs with only cuffs in situ continued to gain weight. Pigs with cuffs and tubes were well with observed effect on weight as compared to cuff only animals. Conclusions: These results suggest that attachment of a cuff to the cardia with a gastrojejunal exclusion tube might be an effective method for treating obese patients at flexible endoscopy. Attachment failures can be overcome with careful attention to device and procedure design.