Gastric Arterial Chemical Embolization: an emerging therapy for severe obesity


Last week, I had the opportunity to watch a surgical technique that is currently being optimized for treatment of severe obesity. It was fascinating to observe, so I thought I'd share some of the highlights!

But first, some background. The general technique, which involves the delivery of an agent that blocks blood flow through the target artery via a catheter, is known as arterial embolization. This procedure is already used in other applications such as stopping internal hemorrhaging. It's a neat concept, for a few reasons. The first is that  only a minor incision is required, making it less intense compared to more invasive surgeries. Secondly, surgeons performing this procedure utilize real-time imaging techniques (such as X-rays) to guide the catheter through the cardiovascular system to deliver the drug with high precision.

Recently, teams of researchers, doctors, and veterinarians (including my mentor and CIGAT director, Dr. Kraitchman) have developed a new application of this procedure: gastric arterial chemical embolization (GACE). Their theory was that by blocking specific tissues in the gastrointestinal system, they could help the body regulate appetite and improve weight-loss in obese patients.

Why obesity? It is common knowledge that obesity can pose a severe health risk to patients. Unfortunately, while there are many existing treatment options from lifestyle changes to surgery, the most effective treatments are also the most costly, the most invasive–and the most risky. 

Recently, it was found that difficulty in losing weight for obese patients could be related to a lack of regulation of the hormone ghrelin. In addition to being the only mammalian hormone known to increase appetite, ghrelin is interesting because the majority is produced by a very specific region of stomach tissue known as the fundus. Furthermore, nutrients are delivered to this tissue by a few specific arteries that can be targeted via embolization. To do so, surgeons deliver small microbeads to block these fundal arteries.

The effects of this process are profound. Without a consistent nutrient flow, ghrelin-producing cells are unable to continue secreting hormone. This causes a dip in ghrelin, which leads to a depressed appetite and decreased weight gain. Furthermore, due to the minimal level of invasiveness and optimization of the procedure, fewer side effects have been observed compared to other surgical interventions.

In fact, in 2015 a team of researchers including Dr. Kraitchman introduced the Bariatric Embolization of Arteries for the Treatment of Obesity (BEAT Obesity), a clinical trial aimed to begin treating patients using this technique.

I must say, the operation was incredibly cool to watch. It was even more incredible considering the surgeons performing the procedure, Dr. Kraitchman and Dr. Clifford Weiss, were part of the team responsible for further developing GACE. It just goes to show that when great minds come together in the name of science and public health, incredible things can happen!


For the first application of GACE: https://pubmed.ncbi.nlm.nih.gov/17581899/

This paper demonstrated the reduction of ghrelin and decreased weight loss post-GACE: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2657856/

Here is a paper introducing the basis of BEAT Obesity: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4414740/


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