Bariatric Arterial Embolization with Calibrated Radiopaque Microspheres and an Antireflux Catheter Suppresses Weight Gain and Appetite-Stimulating Hormones in Swine.

PURPOSE: To examine safety and efficacy of bariatric arterial embolization (BAE) with x-ray-visible embolic microspheres (XEMs) and an antireflux catheter in swine. MATERIAL AND METHODS: BAE with selective infusion of XEMs (n = 6) or saline (n = 4, control) into gastric fundal arteries was performed under x-ray guidance. Weight and plasma hormone levels were measured at baseline and weekly for 4 weeks after embolization. Cone-beam CT images were acquired immediately after embolization and weekly for 4 weeks. Hormone-expressing cells in the stomach were assessed by immunohistochemical staining. RESULTS: BAE pigs lost weight 1 week after embolization followed by significantly impaired weight gain relative to control animals (14.3% vs 20.9% at 4 weeks, P = .03). Plasma ghrelin levels were significantly lower in BAE pigs than in control animals (1,221.6 pg/mL vs 1,706.2 pg/mL at 4 weeks, P < .01). XEMs were visible on x-ray and cone-beam CT during embolization, and radiopacity persisted over 4 weeks (165.5 HU at week 1 vs 158.5 HU at week 4, P = .9). Superficial mucosal ulcerations were noted in 1 of 6 BAE animals. Ghrelin-expressing cell counts were significantly lower in the gastric fundus (17.7 vs 36.8, P < .00001) and antrum (24.2 vs 46.3, P < .0001) of BAE pigs compared with control animals. Gastrin-expressing cell counts were markedly reduced in BAE pigs relative to control animals (98.5 vs 127.0, P < .02). Trichrome staining demonstrated significantly more fibrosis in BAE animals compared with control animals (13.8% vs 8.7%, P < .0001). CONCLUSIONS: XEMs enabled direct visualization of embolic material during and after embolization. BAE with XEMs and antireflux microcatheters was safe and effective.

Anatomical and Technical Considerations for Bariatric Embolization.

Obesity is a well-known major public health concern associated with significant morbidity and mortality. Bariatric arterial embolization (BAE) is a minimally invasive, image-guided therapy that targets hormones linked to obesity by defunctionalizing specific portions of the stomach with the delivery of embolics. The goal of BAE is to induce weight loss through a reduction of appetite-mediating hormones with transarterial embolization of the gastric fundus. This article will review the anatomical and technical considerations for successful BAE.

Bariatric Embolization: A Narrative Review of Clinical Data From Human Trials.

Bariatric arterial embolization (BAE) is a novel technique that is investigated as an alternative, often supplementary, method for weight management. BAE reduces blood perfusion to the gastric fundus, and thus, reduces the production of appetite-inducing hormones. No randomized controlled trial has evaluated the efficacy of BAE to date. Available evidence from published studies include retrospective evaluations of patients undergoing left gastric artery embolization for gastrointestinal bleeding, and early prospective, single-arm clinical trials. Review of clinical data from human trials suggest an average weight loss of about 8-9 kg (ranging 7.6-22.0 kg), corresponding to 8-9% (ranging 4.8-17.2%) of the patients' baseline weight. Common complications include superficial gastric ulcers. Though uncommon, gastric perforation and splenic infarct are important major complication that may arise after left gastric artery embolization. Overall, BAE is an effective, relatively safe procedure that may be associated with clinically significant weight loss in patients with obesity.

Rationale and Preclinical Data Supporting Bariatric Arterial Embolization.

The prevalence of obesity is increasing globally, leading to significantly increased morbidity, mortality, and health care costs. However, there is a lack of effective treatment options that can treat patients with obesity less invasively than with bariatric surgery. Bariatric arterial embolization (BAE) is an image-guided, minimally invasive, percutaneous procedure that is currently being investigated in preclinical animal models and early clinical trials. If successful, BAE may represent a viable interventional approach for obesity treatment. The purpose of this article is to introduce the physiological and anatomical rationale for BAE, review techniques involved in performing BAE for weight modulation, and provide up-to-date preclinical evidence that supports the translation of BAE into patients.

Bariatric Embolization of Arteries for the Treatment of Obesity (BEAT Obesity) Trial: Results at 1 Year.

Background Bariatric embolization is a new endovascular procedure to treat patients with obesity. However, the safety and efficacy of bariatric embolization are unknown. Purpose To evaluate the safety and efficacy of bariatric embolization in severely obese adults at up to 12 months after the procedure. Materials and Methods For this prospective study (NCT0216512 on ClinicalTrials.gov ), 20 participants (16 women) aged 27-68 years (mean ± standard deviation, 44 years ± 11) with mean body mass index of 45 ± 4.1 were enrolled at two institutions from June 2014 to February 2018. Transarterial embolization of the gastric fundus was performed using 300- to 500-µm embolic microspheres. Primary end points were 30-day adverse events and weight loss at up to 12 months. Secondary end points at up to 12 months included technical feasibility, health-related quality of life (Short Form-36 Health Survey ([SF-36]), impact of weight on quality of life (IWQOL-Lite), and hunger or appetite using a visual assessment scale. Analysis of outcomes was performed by using one-sample t tests and other exploratory statistics. Results Bariatric embolization was performed successfully for all participants with no major adverse events. Eight participants had a total of 11 minor adverse events. Mean excess weight loss was 8.2% (95% confidence interval [CI]: 6.3%, 10%; P < .001) at 1 month, 11.5% (95% CI: 8.7%, 14%; P < .001) at 3 months, 12.8% (95% CI: 8.3%, 17%; P < .001) at 6 months, and 11.5% (95% CI: 6.8%, 16%; P < .001) at 12 months. From baseline to 12 months, mean SF-36 scores increased (mental component summary, from 46 ± 11 to 50 ± 10, P = .44; physical component summary, from 46 ± 8.0 to 50 ± 9.3, P = .15) and mean IWQOL-Lite scores increased from 57 ± 18 to 77 ± 18 (P < .001). Hunger or appetite decreased for 4 weeks after embolization and increased thereafter, without reaching pre-embolization levels. Conclusion Bariatric embolization is well tolerated in severely obese adults, inducing appetite suppression and weight loss for up to 12 months. Published under a CC BY-NC-ND 4.0 license. Online supplemental material is available for this article.

Utility of histology for the diagnosis of portal hypertensive gastroenteropathy. Concordance between the endoscopic image and gastrointestinal biopsies. Role of the CD34 marker. / Utilidad de la histología para el diagnóstico de la gastroenteropatía por hipertensión portal. Concordancia entre la imagen endoscópica y las biopsias gastrointestinales. Papel del marcador CD34.

INTRODUCTION: Upper gastroscopy in patients with cirrhosis often reveals non-specific lesions, which are usually oriented as portal hypertensive gastropathy (PHG). However, the diagnosis of PHG can be difficult, both from an endoscopic and histological point of view. The study of CD34 expression, which enhances the endothelial cells of the microvasculature, could help the differential diagnosis. The objectives of this study were to evaluate the correlation between endoscopy and histology in the diagnosis of PHG and to assess the utility of CD34 in the diagnosis of PHG. MATERIAL AND METHODS: The results of immunostaining with CD34 gastric fundus biopsies from 100 cirrhotic patients and 20 controls were compared with the endoscopic images. RESULTS: The correlation between the histology and the endoscopic diagnosis of PHG was very low (kappa=0.15). In addition, the measurement of the diameter of the gastric vessels enhanced by the use of immunohistochemical staining (CD34) did not show good correlation with the endoscopic diagnosis (p=.26) and did not provide relevant information for the histological diagnosis of PHG either. DISCUSSION: The correlation between histology and endoscopy is low for the diagnosis of PHG. The use of immunostaining for CD34 does not seem to improve the diagnostic yield of the histological study.

Gastric varices and splenic vein obstruction during steroid treatment for autoimmune pancreatitis: A case report and literature review.

RATIONALE: Few cases of autoimmune pancreatitis (AIP) complicated by gastric varices, in the absence of splenic vein obstruction, have been described in the medical literature. The findings in this case parallel those of 3 previously described cases from Japan and support a pathologic explanation for the evolution of gastric varices in relation to early splenomegaly and the role of steroid therapy for AIP. PATIENT CONCERNS: A 50-year-old male with a history of transfusion-requiring erosive gastritis and recently diagnosed AIP on steroid therapy for 2 weeks presented with a 2-day history of lightheadedness, abdominal pain, and melena. DIAGNOSIS: Esophagogastroduodenoscopy (EGD) revealed prominent varices in the gastric fundus. An abdominal ultrasound with Doppler demonstrated patency of the splenic, hepatic, and portal veins. Review of previous imaging revealed that the splenic vein and the superior mesenteric vein (SMV) were occluded prior to the diagnosis of AIP and steroid therapy initiation. OUTCOME: Following resolution of hemodynamic instability through fluid resuscitation and blood transfusion, the remainder of his hospital course was uneventful. Subsequent to discontinuation of steroid therapy, he developed near total reocclusion of both the splenic vein and SMV. LESSON: Early steroid treatment should be considered in patients with uncomplicated AIP to prevent the occlusive vascular complications that are frequently associated with the pathophysiology of this disease process.

Optical techniques for perfusion monitoring of the gastric tube after esophagectomy: a review of technologies and thresholds.

Anastomotic leakage is one of the most severe complications after esophageal resection with gastric tube reconstruction. Impaired perfusion of the gastric fundus is seen as the main contributing factor for this complication. Optical modalities show potential in recognizing compromised perfusion in real time, when ischemia is still reversible. This review provides an overview of optical techniques with the aim to evaluate the (1) quantitative measurement of change in perfusion in gastric tube reconstruction and (2) to test which parameters are the most predictive for anastomotic leakage.A Pubmed, MEDLINE, and Embase search was performed and articles on laser Doppler flowmetry (LDF), near-infrared spectroscopy (NIRS), laser speckle contrast imaging (LSCI), fluorescence imaging (FI), sidestream darkfield microscopy (SDF), and optical coherence tomography (OCT) regarding blood flow in gastric tube surgery were reviewed. Two independent reviewers critically appraised articles and extracted the data: Primary outcome was quantitative measure of perfusion change; secondary outcome was successful prediction of necrosis or anastomotic leakage by measured perfusion parameters.Thirty-three articles (including 973 patients and 73 animals) were selected for data extraction, quality assessment, and risk of bias (QUADAS-2). LDF, NIRS, LSCI, and FI were investigated in gastric tube surgery; all had a medium level of evidence. IDEAL stage ranges from 1 to 3. Most articles were found on LDF (n = 12), which is able to measure perfusion in arbitrary perfusion units with a significant lower amount in tissue with necrosis development and on FI (n = 12). With FI blood flow routes could be observed and flow was qualitative evaluated in rapid, slow, or low flow. NIRS uses mucosal oxygen saturation and hemoglobin concentration as perfusion parameters. With LSCI, a decrease of perfusion units is observed toward the gastric fundus intraoperatively. The perfusion units (LDF, LSCI), although arbitrary and not absolute values, and low flow or length of demarcation to the anastomosis (FI) both seem predictive values for necrosis intraoperatively. SDF and OCT are able to measure microvascular flow, intraoperative prediction of necrosis is not yet described.Optical techniques aim to improve perfusion monitoring by real-time, high-resolution, and high-contrast measurements and could therefore be valuable in intraoperative perfusion mapping. LDF and LSCI use perfusion units, and are therefore subjective in interpretation. FI visualizes influx directly, but needs a quantitative parameter for interpretation during surgery.

Effect of ephedrine on gastric conduit perfusion measured by laser speckle contrast imaging after esophagectomy: a prospective in vivo cohort study.

Compromised perfusion due to ligation of arteries and veins in esophagectomy with gastric tube reconstruction often (5-20%) results in necrosis and anastomotic leakage, which relate to high morbidity and mortality (3-4%). Ephedrine is used widely in anesthesia to treat intraoperative hypotension and may improve perfusion by the increase of cardiac output and mean arterial pressure (MAP). This study tests the effect of ephedrine on perfusion of the future anastomotic site of the gastric conduit, measured by laser speckle contrast imaging (LSCI). This prospective, observational, in vivo pilot study includes 26 patients undergoing esophagectomy with gastric tube reconstruction from October 2015 to June 2016 in the Academic Medical Center (Amsterdam). Perfusion of the gastric conduit was measured with LSCI directly after reconstruction and after an increase of MAP by ephedrine 5 mg. Perfusion was quantified in flux (laser speckle perfusion units, LSPU) in four perfusion locations, from good perfusion (base of the gastric tube) toward decreased perfusion (fundus). Intrapatient differences before and after ephedrine in terms flux were statistically tested for significance with a paired t-test. LSCI was feasible to image gastric microcirculation in all patients. Flux (LSPU) was significantly higher in the base of the gastric tube (791 ± 442) compared to the fundus (328 ± 187) (P < 0.001). After administration of ephedrine, flux increased significantly in the fundus (P < 0.05) measured intrapatients. Three patients developed anastomotic leakage. In these patients, the difference between measured flux in the fundus compared to the base of the gastric tube was high. This study presents the effect of ephedrine on perfusion of the gastric tissue measured with LSCI in terms of flux (LSPU) after esophagectomy with gastric tube reconstruction. We show a small but significant difference between flux measured before and after administration of ephedrine in the future anastomotic tissue (313 ± 178 vs. 397 ± 290). We also show a significant decrease of flux toward the fundus.

Bariatric embolization: a new and effective option for the obese patient?

INTRODUCTION: Obesity is a public health epidemic in the United States, which results in significant morbidity, mortality, and cost to the healthcare system. Despite advancements in traditional therapeutic options for the obese patients, there is a treatment gap for patients in whom lifestyle modifications alone have not been successful, but for whom bariatric surgery is not a suitable option. Areas covered: This treatment gap needs to be addressed and thus, complimentary or alternative treatments to lifestyle changes and surgery are urgently needed. Recent evidence suggests that embolization of the gastric fundus ('Bariatric Embolization'), which is predominantly supplied by the left gastric artery, may affect energy homeostasis by decreasing ghrelin production. The purpose of this special report is to discuss the background, rationale and latest data on this topic, as well as provide the latest data from the ongoing BEAT Obesity clinical trial. Expert commentary: A multipronged approach is essential in the treatment of obesity. Bariatric embolization looks to treat the hormonal imbalances which contribute to obesity. If proven successful in the long-term, bariatric embolization represents a potential minimally invasive approach to treat obesity offered by interventional radiologists.

Accessory Splenic Artery: A Rare Cause of Upper Gastrointestinal Bleeding.

Variations in the origin and branching pattern of splenic artery are relatively common and asymptomatic, but the presence of an accessory splenic artery, that too symptomatic, is quite rare. This report describes a 67-year-old male, with no history of liver disease, who presented with recurrent upper gastrointestinal bleeding and was found to have an accessory splenic artery arising from the left gastric artery with submucosal intragastric course and supplying the upper pole of the spleen.

Bariatric Embolization: Pilot Study on the Impact of Gastroprotective Agents and Arterial Distribution on Ulceration Risk and Efficacy in a Porcine Model.

PURPOSE: To assess whether the number of fundal arteries embolized and use of gastroprotective agents have an impact on ghrelin suppression and gastric ulceration rates. MATERIALS AND METHODS: Twenty-two healthy, growing swine (mean, 38.4 kg; range, 30.3-47.0 kg) were evaluated. Six control swine underwent a sham procedure. Gastric embolization was performed by the infusion of 40-µm microspheres selectively into some or all gastric arteries supplying the gastric fundus. In group 1, 6 swine underwent embolization of all 4 arteries to the gastric fundus. In group 2, 5 swine underwent embolization of 2 gastric fundal arteries. In group 3, 5 swine underwent embolization of 1 gastric fundal artery. Animals in groups 2 and 3 were treated with gastroprotective agents (sucralfate and omeprazole). Weight and fasting plasma ghrelin levels were analyzed at baseline and at week 4. Upon animal euthanasia, gross analysis was performed for identification of ulcers. RESULTS: Only group 1 animals exhibited changes in serum ghrelin levels that rendered them significantly lower than those in control animals (P = .049). Group 3 animals exhibited marked elevations in serum ghrelin levels compared with control animals (P = .001). Gross pathologic evaluation revealed 0 ulcers in the control animals, 3 ulcers (50%) in group 1, 2 ulcers (40%) in group 2, and 2 ulcers (40%) in group 3. CONCLUSIONS: Administration of gastroprotective agents and embolization of fewer arteries to the gastric fundus did not prevent gastric ulceration in treated animals. Only animals that underwent embolization of all gastric arteries exhibited significant decreases in serum ghrelin levels.

A Novel Endoscopic Bariatric Procedure: Results of an Experimental Study.

BACKGROUND: Surgical treatment of obesity is characterized by both early and late complications, and thus, there is a need to develop safe and non-invasive techniques. Ghrelin is an orexigenic hormone produced by the fundus of the stomach, which may represent a novel target for obesity management. Unfortunately, numerous attempts to alter ghrelin levels have failed to present significant clinical results. We describe a novel procedure that involves modifying arterial blood flow to the gastric fundus for limiting plasma ghrelin levels. METHODS: A gastroscope was advanced into the gastric fundus of 13 healthy Yorkshire swine, and the fundus was clipped under direct visualization to restrict left gastric artery blood flow. Body weights and ghrelin levels were recorded before and once a week for 4 weeks after the procedure. RESULTS: Compared to controls, gastroscopic clipping of the fundus decreased plasma ghrelin levels and prevented further weight gain in the 4 weeks of follow-up. Immunohistochemistry and histomorphometry revealed reduced numbers of ghrelin-positive cells in the fundus of experimental animals. We also observed thrombosis in submucosal arteries and submucosal fibrosis. Histological studies demonstrated minimal gastric mucosal injury. CONCLUSION: Gastroscopic clipping of the fundus in an experimental porcine model resulted in sustained weight loss and a reduction in plasma ghrelin levels at 1 month post-procedure, with no adverse events. Further experimental studies in human patients are needed to examine the clinical utility of this procedure and to optimize a technique, which can facilitate adequate weight loss while minimizing the risk of mucosal injury.

64Cu-ATSM Hypoxia Positron Emission Tomography for Detection of Conduit Ischemia in an Experimental Rat Esophagectomy Model.

BACKGROUND: We designed a hypoxia-imaging modality to detect ischemia of the gastric conduit after esophagectomy. MATERIALS AND METHODS: A rat esophagectomy model was created using 12-16-week-old, 300-350 g male Sprague-Dawley rats. In the operation group (n=6), partial gastric devascularization was performed by ligating the left gastric artery and the short gastric arteries and an esophagogastric anastomosis was performed. In the control group (n=6), the esophageal-gastric junction was incised and suturing was performed without gastric devascularization. Positron emission tomography (PET) images were taken using a microPET rodent model scanner, 24 h after the initial operation, after injection of 200 µCi 64Cu-diacetyl-bis (N4-methylsemicarbazone) (64Cu-ATSM) and pimonidazole 120 mg/kg. After microPET imaging, autoradiography and immunohistochemistry were performed. RESULTS: The PET image revealed 64Cu-ATSM uptake at the fundus in the operation group 3 h after 64Cu-ATSM injection. The maximum percentage of the injected dose per gram of tissue was higher in the operation group (0.047±0.015 vs. 0.026±0.006, p=0.021). The fundus/liver ratio was also higher in the operation group (0.541±0.126 vs. 0.278±0.049, p=0.002). Upon autoradiography, 64Cu-ATSM uptake was observed in the fundus in the operation group, and was well-correlated to that observed on the PET image. Upon immunohistochemistry, expression of hypoxia-inducible factor 1a and pimonidazole were significantly increased at the fundus and lesser curvature compared to the greater curvature in the operation group. CONCLUSION: Hypoxia PET imaging with 64Cu-ATSM can detect ischemia in a rat esophagectomy model. Further clinical studies are needed to verify whether hypoxia imaging may be useful in humans.

[The method of miniinvasive operation for varicosely-changed veins of gastric fundus].

The laparoscopic operation method was elaborated for prophylaxis arrest of hemorrhage, originated from varicosely-changed (VCH) veins of gastric fundus. Dissection and clipping of a. gastri-ca sinistra is performed and VCH gastric vein is transsected. After gastric fundus mobilization a laparoscopic suturing apparatus is applied on him and the fundus became resected. Additionally the sutures made of nonabsorbable threads are applied above the mechanical sutures line. The method was applied in 2 patients, suffering VCH gastroesophageal veins. Application of the proposed operative intervention method have permitted to reduce significantly the occurrence rate of purulent-septic complications. While follow-up prolong 24 - 30 months the hemorrhage recurrence was not revealed. Application of modem videoendoscopic methods of operation for VCH gastric veins permits to improve significantly the operation results and safety, to reduce the patients stationary treatment time.