Due to fear of complications and other factors, less than 1 percent of individuals who qualify for bariatric surgery undergo this procedure in the U.S. In the last decade, endoscopic techniques have emerged as a third option – beyond pharmacological therapy and bariatric surgery – that offer some patients unique benefits.
Weight loss surgeons at Vanderbilt University Medical Center are now offering endoscopic sleeve gastrectomy (ESG), a minimally invasive procedure comparable to gold standard bariatric surgery, as an alternative to traditional obesity therapies.
“Medication therapies and traditional surgery are not available to some people,” said Matthew Spann, M.D., a bariatric surgeon in Vanderbilt ’s surgical weight loss program. “Endoscopic sleeve gastrectomy fills the gap.”
“Medication therapies and traditional surgery are not available to some people. Endoscopic sleeve gastrectomy fills the gap.”
Bariatric Surgeries vs. ESG
Of the four types of bariatric gastric surgery – adjustable gastric banding, vertical sleeve gastrectomy (VSG), Roux-en y gastric bypass (RYGB), and biliopancreatic diversion – VSG is currently the most commonly performed procedure at 61.4 percent.
“Vertical sleeve gastrectomy is often considered less invasive. However, because it surgically removes about 80 percent of the stomach it is not for everyone,” said Julianna Yang, M.D., an assistant professor in the division of Gastroenterology, Hepatology and Nutrition at Vanderbilt.
In comparison, Spann says, ESG offers lower complication rates and lower costs relative to traditional bariatric surgeries. It requires no incision and minimal downtime, though it occasionally requires an overnight hospital observation stay.
One potential disadvantage is that ESG does not introduce the hormonal changes that contribute to glycemic control in traditional bariatric surgery.
“The top portion of the stomach produces about 90 percent of ghrelin, the hormone involved in the hunger cycle. Removing that portion of the stomach can contribute to dramatically reduced hunger with sleeve gastrectomy and gastric bypass,” Spann said. “With ESG, we don’t necessarily get the hormonal advantage.”
Evidence for Effectiveness
In the ESG procedure, Vanderbilt surgeons use endoscopy and the OverStitch™ Endoscopic Suturing System to place sutures in two rows along the greater curvature of the stomach, resulting in a gastric cavity that forms a tubular sleeve along the lesser curvature. The greater curvature is closed off from the gastroesophageal junction to the prepyloric antrum.
“ESG changes the shape of the stomach; it is folded into itself and is not able to expand to the same degree,” Yang explained, “and because it is done with sutures, it’s reversible.”
ESG has been shown to reduce gastric volume out to two years post-procedure, and increase time required for 50 percent gastric emptying of solids by 90 minutes. In the largest study to date, at six months post-procedure 1,000 patients had lost an average 64 percent of excess body weight and maintained this loss at 18 months. Said Yang, “ESG was beneficial in metabolic outcomes, and patients showed a significant decrease in diabetes, hypertension and hypertriglyceridemia.”
“There is a need for more prospective trials,” Yang noted, “especially comparing ESG plus diet and lifestyle versus diet and lifestyle alone.”
“There is a need for more prospective trials, especially comparing ESG plus diet and lifestyle vs. diet and lifestyle alone.”
Expanding Portfolio of Options
In addition to ESG, Vanderbilt is now performing transoral outlet reduction to treat both weight regain and refractory dumping syndrome following RYGB.
“Providing these procedures under the umbrella of our comprehensive center helps us deliver the best outcomes,” Spann said. “We can continue to monitor patients after the procedure to ensure we’re supporting them on the nutrition and medication side of things.”