Left Ventricular Outflow Tract Obstruction Due to Cardiac Hamartoma.

Hamartoma of mature cardiac myocytes (HMCM) is a rare, benign cardiac tumor. We report a case of a 19-year-old female with an atypical presentation, including significant weight loss and abnormal electrocardiogram. A transthoracic echocardiogram (TTE) revealed a mass causing left ventricular outflow tract (LVOT) obstruction, confirmed by cardiac magnetic resonance (CMR) imaging showing a 5 x 3 cm mass contiguous with the right ventricular free wall and exhibiting heterogeneous, diffuse late gadolinium enhancement. The patient subsequently underwent sternotomy for surgical biopsy and septal myectomy, with histology of the mass being consistent with HMCM. The patient remained asymptomatic during her 6-month follow-up.

Sex differences in heart transplantation - analysis of the national inpatient sample 2012-2019.

INTRODUCTION: Advanced heart failure therapies and heart transplantation (HT) have been underutilized in women. Therefore, we aimed to explore the clinical characteristics and outcomes of HT by sex. METHODS: We conducted a retrospective analysis of adult discharges from the National Inpatient Sample (NIS) between 2012 and 2019. International Classification of Disease (ICD) procedure codes were used to identify those who underwent HT. RESULTS: A total of 20,180 HT hospitalizations were identified from 2012-2019. Among them, 28 % were female. Women undergoing HT were younger (mean age 51 vs. 54.5 years, p<0.001). HT hospitalizations among men were more likely to have atrial fibrillation, diabetes, hypertension, renal failure, dyslipidemia, smoking, and ischemic heart disease. HT hospitalizations among women were more likely to have hypothyroidism and valvular heart disease. HT hospitalizations in women were associated with no significant difference in risk of in-hospital mortality (adjusted odds ratio [OR] 0.82; 95 % confidence interval [CI] 0.58-1.16, p=0.271), no significant difference in length of stay or inflation-adjusted cost. Men were more likely to develop acute kidney injury during HT hospitalization (69.2 % vs. 59.7 %, adjusted OR 0.71, 95 % CI 0.61-0.83, p<0.001). CONCLUSIONS: HT utilization is lower in women. However, most major in-hospital outcomes for HT are similar between the sexes. Further studies are need to explore the causes of lower rates of HT in women.

MDM2 Regulation of HIF Signaling Causes Microvascular Dysfunction in Hypertrophic Cardiomyopathy.

BACKGROUND: Microvasculature dysfunction is a common finding in pathologic remodeling of the heart and is thought to play an important role in the pathogenesis of hypertrophic cardiomyopathy (HCM), a disease caused by sarcomere gene mutations. We hypothesized that microvascular dysfunction in HCM was secondary to abnormal microvascular growth and could occur independent of ventricular hypertrophy. METHODS: We used multimodality imaging methods to track the temporality of microvascular dysfunction in HCM mouse models harboring mutations in the sarcomere genes Mybpc3 (cardiac myosin binding protein C3) or Myh6 (myosin heavy chain 6). We performed complementary molecular methods to assess protein quantity, interactions, and post-translational modifications to identify mechanisms regulating this response. We manipulated select molecular pathways in vivo using both genetic and pharmacological methods to validate these mechanisms. RESULTS: We found that microvascular dysfunction in our HCM models occurred secondary to reduced myocardial capillary growth during the early postnatal time period and could occur before the onset of myocardial hypertrophy. We discovered that the E3 ubiquitin protein ligase MDM2 (murine double minute 2) dynamically regulates the protein stability of both HIF1α (hypoxia-inducible factor 1 alpha) and HIF2α (hypoxia-inducible factor 2 alpha)/EPAS1 (endothelial PAS domain protein 1) through canonical and noncanonical mechanisms. The resulting HIF imbalance leads to reduced proangiogenic gene expression during a key period of myocardial capillary growth. Reducing MDM2 protein levels by genetic or pharmacological methods normalized HIF protein levels and prevented the development of microvascular dysfunction in both HCM models. CONCLUSIONS: Our results show that sarcomere mutations induce cardiomyocyte MDM2 signaling during the earliest stages of disease, and this leads to long-term changes in the myocardial microenvironment.

A Case of Multivessel Coronary Artery Disease and Anomalous Origin of the Right Coronary Artery With a Malignant Course Presenting With Non-exertional Chest Discomfort and Brugada Phenocopy.

Coronary artery anomalies (CAAs) are an uncommon cause of chest pain in the younger population. Misdiagnosis can be detrimental and lead to sudden cardiac deaths. We present a 62-year-old male with a past medical history significant for chest pain history with a workup in 2001 presumed to be non-cardiac in origin from bronchial asthma. He presented from a Micronesian Island for the evaluation of non-exertional chest discomfort. Further workup showed a Brugada type I pattern on ECG and ST wave depressions on anterolateral and inferior leads with associated AVR elevation on exercise stress testing. Further ischemic workup with coronary angiography revealed right dominant circulation with three-vessel coronary artery disease (CAD), including mid-left anterior descending (LAD) artery chronic total occlusion (CTO) with the right to left collaterals, left circumflex, and right coronary artery (RCA) with the accompanied anomalous origin of RCA. The patient underwent surgical correction of the anomalous RCA and coronary artery bypass grafting for the multi-vessel CAD. CAAs are usually found incidentally during ischemic workups similar to this case. Patients with CAAs can be managed conservatively with caution regarding physical activity. However, high-risk patients will warrant surgical treatment to avoid sudden cardiac death. The diagnosis of CAAs can be challenging and prone to misdiagnosis and maltreatment. It may be beneficial to pursue this in younger patients with ischemia-like symptoms. Further studies should be performed to identify the true incidence and guide medical practitioners regarding the risks, costs, and benefits of diagnosing and surgically treating CAAs in the general population.

Eosinophilic Myocarditis Presenting as Cardiac Tamponade: A Diagnostic Challenge.

Eosinophilic myocarditis (EM) is a rare cause of acute heart failure. It can occur secondary to drug hypersensitivity, autoimmune diseases such as vasculitis, idiopathic hypereosinophilic syndrome (HES) or malignancy, but is often under-recognized and underdiagnosed, being confused with other causes of heart failure. While EM is associated with various clinical symptoms, it is rarely associated with cardiac tamponade that requires urgent pericardiocentesis. Here we describe a patient with EM who presented with cardiac tamponade and decompensated heart failure likely secondary to autoimmune disease. LEARNING POINTS: Work-up for hypereosinophilia should include the identification of treatable causes as well as end-organ dysfunction requiring urgent treatment.In patients presenting with acute heart failure and cardiac tamponade of unclear aetiology, eosinophilic myocarditis should be considered whether or not hypereosinophilia is present on presentation.When invoking the diagnosis of eosinophilic myocarditis, extensive efforts should be made to identify primary causes, such as autoimmune conditions including vasculitis.

Ionogels Derived from Fluorinated Ionic Liquids to Enhance Aqueous Drug Solubility for Local Drug Administration.

Gelatin is a popular biopolymer for biomedical applications due to its harmless impact with a negligible inflammatory response in the host organism. Gelatin interacts with soluble molecules in aqueous media as ionic counterparts such as ionic liquids (ILs) to be used as cosolvents to generate the so-called Ionogels. The perfluorinated IL (FIL), 1-ethyl-3-methylpyridinium perfluorobutanesulfonate, has been selected as co-hydrosolvent for fish gelatin due to its low cytotoxicity and hydrophobicity aprotic polar structure to improve the drug aqueous solubility. A series of FIL/water emulsions with different FIL content and their corresponding shark gelatin/FIL Ionogel has been designed to enhance the drug solubility whilst retaining the mechanical structure and their nanostructure was probed by simultaneous SAXS/WAXS, FTIR and Raman spectroscopy, DSC and rheological experiments. Likewise, the FIL assisted the solubility of the antitumoural Doxorubicin whilst retaining the performing mechanical properties of the drug delivery system network for the drug storage as well as the local administration by a syringe. In addition, the different controlled release mechanisms of two different antitumoral such as Doxorubicin and Mithramycin from two different Ionogels formulations were compared to previous gelatin hydrogels which proved the key structure correlation required to attain specific therapeutic dosages.

Initiation of noninvasive surveillance for allograft rejection in heart transplant patients > 1 year after transplant.

BACKGROUND: Gene expression profiling (GEP) and donor-derived, cell-free DNA (dd-cfDNA) measurement are alternative methods to endomyocardial biopsy (EMB) to monitor for rejection following heart transplantation. We aim to describe our use of GEP and dd-cfDNA in heart transplant recipients > 1-year post-transplantation. METHODS: This is a single-center, retrospective study in post-transplant recipients. For patients who were > 1-year post-transplantation and deemed to be at elevated clinical risk for rejection, we collected both GEP and dd-cfDNA every 3 months. Baseline characteristics including GEP, dd-cfDNA levels, rejection episodes, and number of biopsies were obtained. RESULTS: Since July 2019, there were 18 patients being followed with GEP and dd-cfDNA who were > 1-year post-transplantation. Nine EMBs had been performed in seven patients due to as follows; three due to elevated GEP ({greater than or equal to} 34), one due to elevated dd-cfDNA ({greater than or equal to} .20%), two due to elevations of both GEP and dd-cfDNA, two due to clinical rejection and one to follow up a post rejection episode. One of the two biopsies due to elevations of both GEP and dd-cfDNA showed acute cellular rejection grade 2R. None of the biopsies due to either an elevation in the GEP or dd-cfDNA revealed any significant rejection. CONCLUSION: In this study, the use of both GEP and dd-cfDNA led to an increased number of EMB in patients > 1-year post-transplantation. Further studies are needed to validate these findings and evaluate long-term consequences of these diagnostic tests in this population.

Mobility and versatility of the liquid bismuth promoter in the working iron catalysts for light olefin synthesis from syngas.

Liquid metals are a new emerging and rapidly growing class of materials and can be considered as efficient promoters and active phases for heterogeneous catalysts for sustainable processes. Because of low cost, high selectivity and flexibility, iron-based catalysts are the catalysts of choice for light olefin synthesis via Fischer-Tropsch reaction. Promotion of iron catalysts supported by carbon nanotubes with bismuth, which is liquid under the reaction conditions, results in a several fold increase in the reaction rate and in a much higher light olefin selectivity. In order to elucidate the spectacular enhancement of the catalytic performance, we conducted extensive in-depth characterization of the bismuth-promoted iron catalysts under the reacting gas and reaction temperatures by a combination of cutting-edge in situ techniques: in situ scanning transmission electron microscopy, near-atmospheric pressure X-ray photoelectron spectroscopy and in situ X-ray adsorption near edge structure. In situ scanning transmission electron microscopy conducted under atmospheric pressure of carbon monoxide at the temperature of catalyst activation showed iron sintering proceeding via the particle migration and coalescence mechanism. Catalyst activation in carbon monoxide and in syngas leads to liquid bismuth metallic species, which readily migrate over the catalyst surface with the formation of larger spherical bismuth droplets and iron-bismuth core-shell structures. In the working catalysts, during Fischer-Tropsch synthesis, metallic bismuth located at the interface of iron species undergoes continuous oxidation and reduction cycles, which facilitate carbon monoxide dissociation and result in the substantial increase in the reaction rate.

Non-aqueous solvent extraction of indium from an ethylene glycol feed solution by the ionic liquid Cyphos IL 101: speciation study and continuous counter-current process in mixer-settlers.

A solvometallurgical process for the separation of indium(iii) and zinc(ii) from ethylene glycol solutions using the ionic liquid extractants Cyphos IL 101 and Aliquat 336 in an aromatic diluent has been investigated. The speciation of indium(iii) in the two immiscible organic phases was investigated by Raman spectroscopy, infrared spectroscopy, EXAFS and 115In NMR spectroscopy. At low LiCl concentrations in ethylene glycol, the bridging (InCl3)2(EG)3 or mononuclear (InCl3)(EG)2 complex is proposed. At higher lithium chloride concentrations, the first coordination sphere changes to two oxygen atoms from one bidentate ethylene glycol ligand and four chloride anions ([In(EG)Cl4]-). In the less polar phase, indium(iii) is present as a tetrahedral [InCl4]- complex independent of the LiCl concentration. After the number of theoretical stages had been determined using a McCabe-Thiele diagram for extraction by Cyphos IL 101, the extraction and scrubbing processes were performed in lab-scale mixer-settlers to test the feasibility of working in continuous mode. Indium(iii) was extracted quantitatively in four stages, with 19% co-extraction of zinc(ii). The co-extracted zinc(ii) was scrubbed selectively in six stages using an indium(iii) scrub solution. Indium(iii) was recovered from the loaded less polar organic phase as indium(iii) hydroxide (98.5%) by precipitation stripping with an aqueous NaOH solution.

Predicting Transfusions During Left Ventricular Assist Device Implant.

Perioperative bleeding and transfusion cause morbidity and mortality in patients receiving left ventricular assist devices (LVADs). We assessed factors associated with transfusions within 30 days of durable LVAD implantation and the clinical outcomes associated with transfusions. A retrospective cohort study of patients undergoing initial durable LVAD implantation between 2014 and 2016 was performed. Rates of packed red blood cell (PRBC) or other blood product transfusions (platelets or fresh frozen plasma) were assessed. Ordinal multivariable regression analysis was performed to determine factors independently associated with transfusion. Analysis included 156 patients, mean age 54.6 years and 74.4% male, who received a mean of 11.7 units of PRBC and 10.0 units of other products within 30 days. Preimplant mechanical ventilation, dialysis, higher INR, previous sternotomy, higher model for end-stage liver disease score, and lower hemoglobin were associated with increased PRBC transfusion rates. Higher preoperative central venous pressure, mechanical ventilation, concomitant surgical procedures, previous sternotomy, and lower hemoglobin were associated with increased PRBC transfusion rates within 48 hours of implant (adjusted odds ratio [OR] 1.46, P = 0.013 per 5 mm Hg). There were no significant associations with ferritin (adjusted OR 1.00, P = 0.236) or transferrin saturation (adjusted OR 1.17, P = 0.068). Transfusions were associated with an increase in ventilation duration, intensive care unit length of stay, reoperation for bleeding, and all-cause mortality. In patients undergoing LVAD implantation, perioperative blood product exposure is common and associated with increased morbidity and mortality. Elevated central venous pressure and anemia are potentially modifiable factors associated with increased early PRBC transfusion rates.

A novel small molecule A2A adenosine receptor agonist, indirubin-3'-monoxime, alleviates lipid-induced inflammation and insulin resistance in 3T3-L1 adipocytes.

Saturated free fatty acid-induced adipocyte inflammation plays a pivotal role in implementing insulin resistance and type 2 diabetes. Recent reports suggest A2A adenosine receptor (A2AAR) could be an attractive choice to counteract adipocyte inflammation and insulin resistance. Thus, an effective A2AAR agonist devoid of any toxicity is highly appealing. Here, we report that indirubin-3'-monoxime (I3M), a derivative of the bisindole alkaloid indirubin, efficiently binds and activates A2AAR which leads to the attenuation of lipid-induced adipocyte inflammation and insulin resistance. Using a combination of in silico virtual screening of potential anti-diabetic candidates and in vitro study on insulin-resistant model of 3T3-L1 adipocytes, we determined I3M through A2AAR activation markedly prevents lipid-induced impairment of the insulin signaling pathway in adipocytes without any toxic effects. While I3M restrains lipid-induced adipocyte inflammation by inhibiting NF-κB dependent pro-inflammatory cytokines expression, it also augments cAMP-mediated CREB activation and anti-inflammatory state in adipocytes. However, these attributes were compromised when cells were pretreated with the A2AAR antagonist, SCH 58261 or siRNA mediated knockdown of A2AAR. I3M, therefore, could be a valuable option to intervene adipocyte inflammation and thus showing promise for the management of insulin resistance and type 2 diabetes.

Utilizing mobile technologies to improve physical activity and medication adherence in patients with heart failure and diabetes mellitus: Rationale and design of the TARGET-HF-DM Trial.

Heart failure (HF) and diabetes mellitus (DM) are major public health issues that place significant burden on patients and health care systems. Patients with both HF and DM are at higher risk of adverse cardiovascular and HF outcomes than those with either disease in isolation. Different antihyperglycemic medications (even within the same medication class) have conflicting results of benefit or harm in patients with established and incident HF. Recent data highlight the importance of a renewed focus on optimal pharmacotherapy for this population with DM and HF (or at risk for HF). Both HF and DM require major lifestyle modification for optimal management, in terms of both optimizing health behaviors (eg, physical activity, diet) and adherence to complex medical and self-care regimens. Mobile health (mHealth) technologies (eg, apps, wearables) are widely available in the community and may play a role in optimizing the health status of patients; however, there is limited and conflicting information on whether such technologies are actually beneficial in at-risk populations. In this article, we summarize current strategies, including mobile health interventions, to improve physical activity levels, drug adherence, and outcomes in patients with DM, HF, or both and describe the design and rationale for the Technologies to improve drug Adherence and Reinforce Guideline based Exercise Targets in patients with heart Failure and Diabetes Mellitus trial, which is designed to test the efficacy of using mHealth technology to improve health behaviors and outcomes in this high-risk population.

Right ventricular load adaptability metrics in patients undergoing left ventricular assist device implantation.

OBJECTIVE: Several right load adaptability metrics have been proposed as predictors of right heart failure (RHF) following left ventricular assist device implantation. This study sought to validate and compare the prognostic value of these indices. METHODS: This retrospective study included 194 patients undergoing continuous-flow left ventricular assist device implantation. The primary end point was unplanned right atrial assist device (RVAD) need within 30 days after left ventricular assist device implantation; the secondary end points included clinical RHF syndrome without RVAD need and the composite of RHF or RVAD need. Load adaptability indices or interventricular ratios were divided into surrogates of ventriculoarterial coupling (RV area change:end-systolic area), indices reflecting adaptation proportionality (Dandel's index = tricuspid regurgitation velocity-time integral normalized for average RV radius in diastole or systole), and simple ratios (eg, pulse pressure:right atrial pressure or right arterial pressure:pulmonary arterial wedge pressure). RESULTS: Mean age was 55 ± 13 years with 77% of men. RHF occurred in 75 patients with 30 patients requiring RVAD implantation. Among right heart metrics, right arterial pressure (normalized odd ratio, 1.62; 95% confidence interval, 1.15-2.38), right arterial pressure:pulmonary arterial wedge pressure (normalized odds ratio, 1.59; 95% confidence interval, 1.08-2.32) and pulse pressure:right arterial pressure < 2.0 (normalized odds ratio, 2.56; 95% confidence interval, 1.16-5.56) were associated with RVAD need (all P values < .02). These 3 metrics significantly added incremental prognostic value to the Interagency Registry for Mechanically Assisted Circulatory Support classification score in a similar range, whereas only RAP was incremental to the Michigan score. Correlates of RHF not requiring RVAD included RV end-systolic area index and the Dandel indices, which provided similar incremental value to the Interagency Registry for Mechanically Assisted Circulatory Support, Michigan, and European Registry for Patients with Mechanical Circulatory Support scores. CONCLUSIONS: Although associated with outcome, right load adaptability indices do not appear to provide strong incremental value when compared with simple metrics.

Planned Concomitant Left and Right Ventricular Assist Device Insertion to Avoid Long-term Biventricular Mechanical Support: Bridge to Right Ventricular Recovery.

INTRODUCTION: The planned use of a temporary right ventricular assist device (RVAD) at the time of left ventricular assist device (LVAD) implantation may prevent the need for a permanent biventricular assist device (BiVAD). Herein we describe our RVAD weaning protocol that was effectively employed in 4 patients to prevent the need for permanent BiVAD. METHODS: Four patients in refractory cardiogenic shock underwent planned RVAD insertion during LVAD implantation due to severely depressed right ventricular function with dilation preoperatively. A standardized RVAD weaning protocol was employed in these 4 patients in preparation for decannulation. RESULTS: Temporary RVADs were successfully placed in all 4 patients at the time of LVAD implantation. All patients survived to RVAD decannulation and discharge and were alive at the time of most recent follow-up (range, 528-742 days post-RVAD decannulation). CONCLUSION: Planned implantation of a temporary RVAD in high risk patients may avoid the need for biventricular mechanical support in the future.

Multicenter experience with durable biventricular assist devices.

BACKGROUND: Severe right ventricular failure necessitating a right ventricular assist device (RVAD) complicates 6% to 11% of left ventricular assist device (LVAD) implants. Patient outcomes for those receiving durable continuous-flow VADs in a biventricular configuration (i.e., BiVAD) have been reported in limited case series. METHODS: Data from United States centers with ≥ 6 BiVAD implants were collected. Characteristics and outcomes of patients receiving contemporaneous (i.e., same surgery) vs staged implantation of the HVAD as a BiVAD were compared. RESULTS: From 2011 to 2017, 46 patients received durable BiVADs and had the following characteristics: median age, 46 years (interquartile range [IQR], 19-67 years), non-ischemic cardiomyopathy (80%), bridge to transplant (83%), Interagency Registry for Mechanically Assisted Circulatory Support Profile 1 or 2 (92%), use of temporary circulatory support (37%), right atrial pressure 19 mm Hg (IQR, 14-23 mm Hg), and cardiac index of 1.6 liters/min/m2 (IQR, 1.2-2.1 liters/min/m2). Operative mortality was 33%. Equal numbers of patients received a right atrial or right ventricular implant. Contemporaneous BiVAD implantation occurred in 31 patients (67%), and compared with 15 patients (33%) with staged implants, these patients had a shorter intensive care unit length of stay of 12 days (IQR, 7-23 days) vs 42 days (IQR, 28-48 days, p = 0.035) and were more likely to be discharged from the hospital on BiVAD support (61% vs 27%, p = 0.04). RVAD thrombosis developed in 17 patients (37%). Patients with contemporaneous BiVAD implants had a 1-year survival of 74% compared with 40% in staged BiVAD patients (p = 0.11). CONCLUSIONS: Patients receiving durable BiVADs represent a critically ill patient population with severe biventricular failure who have high operative mortality and RVAD thrombosis rates. The 1-year survival for patients receiving contemporaneous BiVADs in experienced centers mirrors other contemporary durable biventricular support strategies.

Inflammation-induced mTORC2-Akt-mTORC1 signaling promotes macrophage foam cell formation.

The transformation of macrophages into lipid-loaded foam cells is a critical and early event in the pathogenesis of atherosclerosis. Several recent reports highlighted that induction of TLR4 signaling promotes macrophage foam cell formation; however, the underlying molecular mechanisms have not been clearly elucidated. Here, we found that the TLR4 mediated inflammatory signaling communicated with mTORC2-Akt-mTORC1 metabolic cascade in macrophage and thereby promoting lipid uptake and foam cell formation. Mechanistically, LPS treatment markedly upregulates TLR4 mediated inflammatory pathway which by activating mTORC2 induces Akt phosphorylation at serine 473 and that aggravate mTORC1 dependent scavenger receptors expression and consequent lipid accumulation in THP-1 macrophages. Inhibition of mTORC2 either by silencing Rictor expression or inhibiting its association with mTOR notably prevents LPS induced Akt activation, scavenger receptors expression, and macrophage lipid accumulation. Although suppression of mTORC1 expression by genetic knockdown of Raptor did not produce any significant change in Akt S473 phosphorylation, however, incubation with Akt activator in Rictor silenced cells failed to promote scavenger receptors expression and macrophage foam cell formation. Thus, present research explored the signaling pathway involved in inflammation-induced macrophage foam cells formation and therefore, targeting this pathway might be useful for preventing macrophage foam cell formation.

Polycapillary Optics Based Confocal Micro X-ray Fluorescence and X-ray Absorption Spectroscopy Setup at The European Synchrotron Radiation Facility Collaborative Research Group Dutch-Belgian Beamline, BM26A.

A novel plug-and-play setup based on polycapillary X-ray optics enables three-dimensional (3D) confocal X-ray fluorescence (XRF) and X-ray absorption spectroscopy down to 8 × 8 × 11 µm3 (17 keV) at the European Synchrotron Radiation Facility Collaborative Research Group Dutch-Belgian Beamline, BM26A. A complete description and analytical characterization is presented, together with two recently performed experimental cases. In Deep Earth diamond São Luiz-Frankfurt am Main 16, an olivine-rich inclusion was mapped with full 3D XRF elemental imaging. The preliminary tests on Iron Gall ink contained in an historical document, a letter from the court of King Philip II of Spain, reveal both the delicate nature of Iron Gall ink and the lack of Fe-Ni chemical bonding.

Efficacy of Video Capsule Endoscopy in the Management of Suspected Small Bowel Bleeding in Patients With Continuous Flow Left Ventricular Assist Devices.

BACKGROUND: Continuous flow left ventricular assist device (CF-LVAD) patients have a high prevalence of gastrointestinal bleeding from the small bowel. Video capsule endoscopy (VCE) is often used for diagnosis in these patients, but efficacy has yet to be determined. In this study, we evaluated the efficacy of VCE in the management of CF-LVAD patients with suspected small bowel bleeding by comparing to a non-VCE CF-LVAD control group. METHODS: We retrospectively reviewed the charts of all patients with CF-LVADs implanted at Stanford Hospital from January 2010 to October 2015. Patients were included in the study if there was a clinical suspicion of small bowel bleeding and either a negative upper endoscopy or colonoscopy. RESULTS: A total of 26 patients met inclusion criteria for a total of 15 encounters where VCE was done, and 25 where VCE was not done. There were no statistical differences when comparing these groups in terms of medical therapy use (thalidomide or octreotide), enteroscopy use (double-balloon or push), intervention on lesions, or any 30-day outcomes. There was no advantage to VCE with regard to the composite endpoint time to re-bleed or death related to re-bleeding (median 114 vs. 161 days, P = 0.15) after removing patients who did not get a VCE due to death or critical illness. CONCLUSIONS: We did not find VCE changed management or outcomes in CF-LVAD patients with suspected small bowel bleeding at our institution when compared to a non-VCE control group. Our experience is small and single center, and larger, multi-center studies could further elucidate the utility of VCE in this patient population.

Superior Stability of Au/SiO2 Compared to Au/TiO2 Catalysts for the Selective Hydrogenation of Butadiene.

Supported gold nanoparticles are highly selective catalysts for a range of both liquid-phase and gas-phase hydrogenation reactions. However, little is known about their stability during gas-phase catalysis and the influence of the support thereon. We report on the activity, selectivity, and stability of 2-4 nm Au nanoparticulate catalysts, supported on either TiO2 or SiO2, for the hydrogenation of 0.3% butadiene in the presence of 30% propene. Direct comparison of the stability of the Au catalysts was possible as they were prepared via the same method but on different supports. At full conversion of butadiene, only 0.1% of the propene was converted for both supported catalysts, demonstrating their high selectivity. The TiO2-supported catalysts showed a steady loss of activity, which was recovered by heating in air. We demonstrated that the deactivation was not caused by significant metal particle growth or strong metal-support interaction, but rather, it is related to the deposition of carbonaceous species under reaction conditions. In contrast, all the SiO2-supported catalysts were highly stable, with very limited formation of carbonaceous deposits. It shows that SiO2-supported catalysts, despite their 2-3 times lower initial activities, clearly outperform TiO2-supported catalysts within a day of run time.