Weight loss after sleeve gastrectomy varies from patient to patient. Many factors contribute to this variation. Accelerated gastric emptying after sleeve gastrectomy is one of those contributing factors that greatly affect the degree of weight loss after bariatric surgery.
Indeed, one of the most important mechanisms of actions of sleeve gastrectomy in terms of weight loss is stimulating gut hormone secretion. Gut hormones like GLP-1 (Glucagon like peptide), is secreted by intestines in response to food emptying from stomach. GLP-1, commercially synthesized and sold under the name of Ozempic, Mounjaro… curbs appetite leading to decreased food intake and weight loss.
It is well known that dumping or accelerated gastric emptying stimulates gut hormone secretion. Therefore, gastric sleeve surgery that best accelerates gastric emptying is associated with best weight loss outcome.
An interesting publication titled “Delayed gastric emptying after sleeve gastrectomy is associated with poor weight loss” was published in 2022 in Obesity surgery journal. The authors demonstrated a strong correlation between poor weight loss following sleeve gastrectomy and gastric emptying rate. They showed a pattern of meal retention in the proximal sleeve lumen in most patients with poor weight loss after sleeve gastrectomy. This is most likely due to narrowing of incisura angularis (the natural stomach angulation between its horizontal and vertical parts), a common mistake among bariatric surgeons. Narrowing of the incisura angularis secondary to aggressive stomach resection over a small bougie size leads to neo-fundus formation. Neo-fundus is the dilation of the proximal gastric sleeve lumen due to functional narrowing of sleeve lumen most commonly at the incisura angularis. From a weight loss mechanistic point of view, this finding is quite significant. It basically shows that bariatric surgeons who aggressively resect the stomach to achieve the best weight loss, end up with the poorest weight loss outcomes. For the mechanism of action of sleeve gastrectomy does not rely on mechanical restriction secondary to stomach volume reduction. Rather, physiological changes in gut neuro-hormone signaling secondary to accelerated food emptying from stomach into intestines lead to weight loss after sleeve gastrectomy.
From this perspective, the best weight loss after sleeve gastrectomy is achieved by resecting the stomach in a way that best accelerates gastric emptying. Consequently, avoiding a narrowed incisura angularis is strongly recommended during sleeve surgery to achieve best weight loss. At Houston Weight loss Surgery Center, we have adopted this approach since 2014. Not only did we achieve great weight loss results in our sleeve gastrectomy patient population, but we have also achieved a 0% rate of post-sleeve gastrectomy staple line leak and acid reflux. Indeed, by avoiding a narrowed incisura angularis, the risk of staple line leak at the upper part of the sleeve lumen goes down to zero. The risk of post-op GERD also greatly diminishes with this approach. At Houston Weight Loss Surgery Center, pre-operative acid reflux and hiatal hernia are not contraindication for sleeve gastrectomy. Our data clearly show resolution of GERD following a properly performed hiatal hernia repair and sleeve gastrectomy. A sleeve gastrectomy that does not narrow the incisura angularis, thus leading to accelerated gastric emptying.