Bariatric embolization using large calibrated spheres (300-500 μm): safety and long-term efficacy in a swine model

No: LB01 Bariatric embolization of arteries for the treatment of obesity (BEAT obesity): study design and initial safety/efficacy data C.R. Weiss, L. Cheskin, A.M. Fischman, B. Holly, R.S. Patel, K. Paudel, E. Shin, K. Steele, T.H. Moran, D.L. Kraitchman, A. Arepally; Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, United States; School of Public Health, Johns Hopkins University, Baltimore, MD, United States; Radiology, Mount Sinai, New York, NY, United States; Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, United States; Surgery, Johns Hopkins University School of Medicine, Baltimore, MD, United States; Psychiatry, Johns Hopkins University School of Medicine, Baltimore, MD, United States; Radiology, Piedmont Healthcare, Atlanta, GA, United States. Purpose: Bariatric embolization is a new endovascular procedure that has been developed for the treatment of obesity. This procedure, in which the gastric fundus is embolized with small particles via the left gastric artery, has shown great promise in animal studies. BEAT obesity is an investigator initiated IDE, approved by the FDA designed to assess the safety and efficacy of bariatric embolization to treat morbidly obese patients using 300-500 micron embospheres. Materials: This single-arm prospective pilot study enrolls morbidly obese (BMI of 40-60 and weight o400 lbs) adult patients without comorbid conditions. Exclusion criteria includes: history of malignancy, vascular disease, prior abdominal surgery, diabetes, variant gastric arterial anatomy, and peptic ulcer disease are excluded from this study. Primary endpoints include: weight loss and 30-day adverse events. Secondary endpoints (12 months of follow-up) include: blood pressure, lipid profile, serum obesity hormones (Ghrelin, Leptin, GLP-1, PYY), eating and hunger/satiety assessments, Quality of Life Parameters, results from endoscopy and gastric emptying studies. Key aspects of the study design include: 1) Preprocedural CTA, upper endoscopy, gastric emptying study, gastric hormone panels, well as quality of life and obesityrelated psychological assessment; 2) post-procedural endoscopy (week 2, month 3) and gastric emptying studies (month 1, month 6), full lab and gastric hormone panels, well as quality of life and obesity-related psychological assessments (weeks 1, 2 and months 1,3,6,12). The procedure specifics include celiac and selective left gastric artery DSA and cone beam CTs, followed by embolization with 300-500 micron embospheres. Results: As of this submission we have enrolled 4 of our 5 initial patients. We will present initial 30-day safety data, including procedural details, laboratory, endoscopy and gastric emptying results. Conclusions: BEAT obesity is an investigator initiated IDE, approved by the FDA, designed to assess the safety and efficacy of bariatric embolization to treat the morbidly obese. We have enrolled 4 of our initial 5 patients and the primary endpoint of 30-day safety and efficacy will be presented. Abstract No: LB02 Bariatric embolization using large calibrated spheres (300-500 μm): safety and long-term efficacy in a swine model C.R. Weiss, A. Arepally, K. Paudel, J. Singh, C. Hu, E. Shin, R. Anders, T.H. Moran, D.L. Kraitchman; Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, United States; Biomedical Engineering, Johns Hopkins University, Baltimore, MD, United States; Radiology, Piedmont Healthcare, Atlanta, GA, United States; Material Science and Engineering, Johns Hopkins University, Baltimore, MD, United States; Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, United States; Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, United States; Pathology, Johns Hopkins University School of Medicine, Baltimore, MD, United States; Molecular and Comparative Pathobiology, Johns Hopkins University, Baltimore, MD, United States. Purpose: Preclinical studies of bariatric arterial embolization (BAE) with small calibrated spheres in growing swine have been effective in preventing weight gain and altering gastric hormone profiles. To date no studies have examined the effectiveness of larger size embolic beads. The current study examines the use of larger microspheres (300-500mm) in combination with C-arm cone beam CT (CBCT) and an anti-reflux catheter in growing pigs to investigate the effects on weight gain, gastric motility, and the gastric neuro-hormonal axis. Materials: Fundal artery targeting using CBCT (dynaCT, Siemens AXIOM Artis Zee, 8s DSA, 2101 rotation, 0.51/step) was performed in 55-60lb juvenile farm pigs (n1⁄45 BAE, n1⁄45 sham). From a celiac DSA, two of the three fundal arteries were selected with a SureFire mt catheter (SureFire Medical) and 0.016 Fathom wire (Boston Scientific). At each location a pre-embolization DSA and CBCT (20-25% contrast IA for 8 s @ 2-3cc/s) were performed. In the BAE group, 300-500mm Embospheres (Merit Medical) were delivered until stasis; the sham group received saline. Weights and blood samples (for ghrelin, GLP-1, PYY) were collected serially for 16 weeks. Upper endoscopy was performed at 1 week post-BAE and gastric emptying (oral acetaminophen technique) was performed at 3-5 weeks post-BAE. Statistical analysis was performed (STATA, Po0.05 considered statistically significant). Results: Weight gain was not different in BAE animals relative to sham pigs at any time point (0.32 2.7 vs. 1.14 2.7lb @1 week; 12.98 6.23 vs. 11.54 5.6lb @ 4 weeks; 47.72 5.9 vs. 51.42 3.7lb @ 16 weeks, BAE vs. sham, respectively). Gastric emptying was not altered by BAE. GLP-1 in response to feeding did not significantly differ between treated and sham pigs. Superficial mucosal ulcers in the gastric fundus were present in 2 of 5 pigs. Conclusions: Bariatric embolization using larger beads (300500mm) did not produce significant weight loss, changes in gastric emptying, or changes in GLP-1. This suggests that a smaller caliber bead size may be more effective for bariatric embolization.