Tyler James Harris MD, Presenter: Nothing to Disclose

Timothy Patrick Murphy MD, Abstract Co-Author: Nothing to Disclose

Bryan Scott Jay MD, Abstract Co-Author: Nothing to Disclose

Christopher O'Hara Hampson MD, Abstract Co-Author: Nothing to Disclose

Abdul Mueed Zafar, Abstract Co-Author: Nothing to Disclose

Obesity is a burgeoning health epidemic with a myriad of secondary health problems. Existing surgical options are rife with potential complications and are often unsuccessful. We aim to explore the feasibility and survivability of a minimally invasive treatment for morbid obesity in a Yorkshire swine model. We will modulate blood flow in the intestine using a flow-restricting stent-graft in the superior mesenteric artery (SMA). This procedure is expected to result in pain and/or diarrhea with excess food intake. Animals are expected to reduce their food intake to avoid pain. This adaption will cause weight loss.

All work was conducted in a dedicated animal facility on hospital grounds under the approval of the Institutional Animal Care Use Committee. A cut down was performed in three Yorkshire swine with direct femoral arterial puncture. The GDA was embolized if visualized. Thereafter, a stent-graft was positioned in the proximal SMA. In one pig, simultaneous pressures were measured across the stent. Pigs were then monitored over a two to six week post-operative period and were then weighed and sacrificed. A repeat mesenteric angiogram was performed in one test pig given preliminary clinical findings.

Four stent-grafts were successfully placed in 3 test animals without fatality or unplanned euthanasia. The stent was flow limiting in one pig (#690) per intraoperative pressure gradient. In the initial post-operative period, this pig demonstrated a reduced rate of weight gain. This pig also developed diarrhea and demonstrated subjectively decreased oral intake. This reduced rate of weight gain normalized during post procedure weeks 3-8, with polynomial line of best fit demonstrating mild persistent reduction in weight gain. Follow-up angiogram on pig #690 demonstrated development of collateral blood supply from the IMA supplying the SMA territory.

Flow-reducing stent graft placement is safe and feasible. There was a modest reduction in the rate of weight gain attenuated by recruitment of unanticipated collateral flow after the initial post-procedure period. Planned further work will incorporate embolization of IMA collateral vessels.

Flow-limiting stent-graft placement in mesenteric arteries holds promise as potential therapy for morbid obesity given preliminary animal model results, and further evaluation is planned.

Harris, T, Murphy, T, Jay, B, Hampson, C, Zafar, A, Visceral Blood Flow Modulation Therapy for Morbid Obesity.  Radiological Society of North America 2011 Scientific Assembly and Annual Meeting, November 26 - December 2, 2011 ,Chicago IL. http://archive.rsna.org/2011/11016586.html