Gastric supply manipulation to modulate ghrelin production and enhance vascularization to the cardia: proof of the concept in a porcine model.

INTRODUCTION: Selective embolization of the left-gastric artery (LGA) reduces levels of ghrelin and achieves significant short-term weight loss. However, embolization of the LGA would prevent the performance of bariatric procedures because the high-risk leakage area (gastroesophageal junction [GEJ]) would be devascularized. AIM: To assess an alternative vascular approach to the modulation of ghrelin levels and generate a blood flow manipulation, consequently increasing the vascular supply to the GEJ. MATERIALS AND METHODS: A total of 6 pigs underwent a laparoscopic clipping of the left gastroepiploic artery. Preoperative and postoperative CT angiographies were performed. Ghrelin levels were assessed perioperatively and then once per week for 3 weeks. Reactive oxygen species (ROS; expressed as ROS/mg of dry weight [DW]), mitochondria respiratory rate, and capillary lactates were assessed before and 1 hour after clipping (T0 and T1) and after 3 weeks of survival (T2), on seromuscular biopsies. A celiac trunk angiography was performed at 3 weeks. RESULTS: Mean (±standard deviation) ghrelin levels were significantly reduced 1 hour after clipping (1902 ± 307.8 pg/mL vs. 1084 ± 680.0; P = .04) and at 3 weeks (954.5 ± 473.2 pg/mL; P = .01). Mean ROS levels were statistically significantly decreased at the cardia at T2 when compared with T0 (0.018 ± 0.006 mg/DW vs. 0.02957 ± 0.0096 mg/DW; P = .01) and T1 (0.0376 ± 0.008 mg/DW; P = .007). Capillary lactates were significantly decreased after 3 weeks, and the mitochondria respiratory rate remained constant over time at the cardia and pylorus, showing significant regional differences. CONCLUSIONS: Manipulation of the gastric flow targeting the gastroepiploic arcade induces ghrelin reduction. An endovascular approach is currently under evaluation.

Embolization of arterial gastric supply in obesity (EMBARGO): an endovascular approach in the management of morbid obesity. proof of the concept in the porcine model.

BACKGROUND: Embolization of the left gastric artery (LGA) reduces circulating levels of ghrelin, but might prevent from further obesity surgery, particularly sleeve gastrectomy (SG), since the gastroesophageal junction (GEJ), depending on LGA, would be devascularized. Our aim was to evaluate, in an experimental animal study, an endovascular approach targeting arteries of the gastroepiploic arcade aiming to modulate ghrelin levels and to generate an increased vascular supply of the GEJ to reduce the risks of staple-line leaks after SG. METHODS: Seven pigs underwent embolization of both left and right gastroepiploic arteries (LGEA and RGEA) using 500-700-µ microspheres (embolization of arterial gastric supply in obesity (EMBARGO)-alpha). A SG was performed in six pigs 3 weeks after EMBARGO-alpha and on eight controls. Capillary lactates were measured at the cardia and pylorus. Five pigs underwent coiling of RGEA and embolization of LGEA using both coils and 100-300-µ microspheres (EMBARGO-beta). Ghrelin levels were assessed before and once per week after both EMBARGOs. Control celiac trunk angiography was performed at 3 weeks (alpha) and 4 weeks (beta). RESULTS: No significant ghrelin reduction was obtained with EMBARGO-alpha at 3 weeks when compared to baseline. Significant ghrelin reduction was found 3 weeks (p = 0.0363) and 4 weeks (p = 0.025) after EMBARGO-beta. Post-EMBARGO-alpha animals presented a significantly lower increase in cardia lactates when compared to controls after SG. Control angiography showed a significantly increased fundic vascular network in 5/6 animals after EMBARGO-alpha and in 5/5 after EMBARGO-beta. CONCLUSIONS: EMBARGO is effective to decrease ghrelin production and can enhance the vascular supply of the GEJ, preparing the vascular background for a SG.