Edoxaban-based versus vitamin K antagonist-based antithrombotic regimen after successful coronary stenting in patients with atrial fibrillation (ENTRUST-AF PCI): a randomised, open-label, phase 3b trial

BACKGROUND

We aimed to assess the safety of edoxaban in combination with P2Y12 inhibition in patients with atrial fibrillation who had percutaneous coronary intervention (PCI).

METHODS

ENTRUST-AF PCI was a randomised, multicentre, open-label, non-inferiority phase 3b trial with masked outcome evaluation, done at 186 sites in 18 countries. Patients had atrial fibrillation requiring oral anticoagulation, were aged at least 18 years, and had a successful PCI for stable coronary artery disease or acute coronary syndrome. Participants were randomly assigned (1:1) from 4 h to 5 days after PCI using concealed, stratified, and blocked web-based central randomisation to either edoxaban (60 mg once daily) plus a P2Y12 inhibitor for 12 months or a vitamin K antagonist (VKA) in combination with a P2Y12 inhibitor and aspirin (100 mg once daily, for 1-12 months). The edoxaban dose was reduced to 30 mg per day if one or more factors (creatinine clearance 15-50 mL/min, bodyweight ≤60 kg, or concomitant use of specified potent P-glycoprotein inhibitors) were present. The primary endpoint was a composite of major or clinically relevant non-major (CRNM) bleeding within 12 months. The primary analysis was done in the intention-to-treat population and safety was assessed in all patients who received at least one dose of their assigned study drug. This trial is registered with ClinicalTrials.gov, NCT02866175, is closed to new participants, and follow-up is completed.

FINDINGS

From Feb 24, 2017, through May 7, 2018, 1506 patients were enrolled and randomly assigned to the edoxaban regimen (n=751) or VKA regimen (n=755). Median time from PCI to randomisation was 45·1 h (IQR 22·2-76·2). Major or CRNM bleeding events occurred in 128 (17%) of 751 patients (annualised event rate 20·7%) with the edoxaban regimen and 152 (20%) of 755 patients (annualised event rate 25·6%) patients with the VKA regimen; hazard ratio 0·83 (95% CI 0·65-1·05; p=0·0010 for non-inferiority, margin hazard ratio 1·20; p=0·1154 for superiority).

INTERPRETATION

In patients with atrial fibrillation who had PCI, the edoxaban-based regimen was non-inferior for bleeding compared with the VKA-based regimen, without significant differences in ischaemic events.

FUNDING

Daiichi Sankyo.

Development of a novel prohealing stent designed to deliver sirolimus from a biodegradable abluminal matrix

BACKGROUND

We aimed to demonstrate that, by separating endothelial progenitor cell capture from sirolimus delivery through the application of drug to the abluminal surface of the stent, the degree of endothelialization can be enhanced.

METHODS AND RESULTS

Stainless steel R Stents, with biodegradable SynBiosys polymer coating with sirolimus abluminally applied and surface modified with anti-CD34 antibody were prepared at 2 dosages (low-dose sirolimus [LD-Combo, 2.5 microg sirolimus/mm] and full-dose sirolimus [Combo, 5 microg sirolimus/mm). These Combo stents and the Cypher stent (10 microg sirolimus/mm) were deployed in 98 normal porcine arteries and harvested for pharmacokinetic analysis at 0.25, 1, 3, 7, 14, 28, and 35 days. The LD-Combo stents showed faster early release (50%total dose in 72 hours) than the Combo and Cypher. At 30 days, drug release was near complete with both Combo stents, whereas 20% of drug remained on the Cypher stents. To assess efficacy, a total of 50 stents (Xience V=8, Cypher=8, Genous bioengineered R stent=6, LD-Combo=14, and Combo=14) were implanted in 18 pigs for 14 and 28 days. Optical coherence tomography was performed, and stents were harvested for histology. At 28 days, there was less neointimal thickness with Combo (0.173+/-0.088 mm) compared with Cypher (0.358+/-0.225 mm), LD-Combo (0.316+/-0.228 mm), and Xience V (0.305+/-0.252 mm; P<0.00001). Immunohistochemical analysis of endothelialization showed that Genous bioengineered R stent had the highest degree of platelet endothelial cell adhesion molecule expression (87%) followed by the Combo (75%), LD-Combo (65%), and Cypher (58%).

CONCLUSIONS

Both optical coherence tomography and histology demonstrate that anti-CD34 sirolimus-eluting stents promote endothelialization while reducing neointimal formation and inflammation.

Gene set enrichment analysis identifies key innate immune pathways in primary graft dysfunction after lung transplantation

We hypothesized alterations in gene expression could identify important pathways involved in transplant lung injury. Broncho alveolar lavage fluid (BALF) was sampled from donors prior to procurement and in recipients within an hour of reperfusion as part of the NIAID Clinical Trials in Organ Transplantation Study. Twenty-three patients with Grade 3 primary graft dysfunction (PGD) were frequency matched with controls based on donor age and recipient diagnosis. RNA was analyzed using the Human Gene 1.0 ST array. Normalized mRNA expression was transformed and differences between donor and postreperfusion values were ranked then tested using Gene Set Enrichment Analysis. Three-hundred sixty-two gene sets were upregulated, with eight meeting significance (familywise-error rate, FWER p-value <0.05), including the NOD-like receptor inflammasome (NLR; p < 0.001), toll-like receptors (TLR; p < 0.001), IL-1 receptor (p = 0.001), myeloid differentiation primary response gene 88 (p = 0.001), NFkB activation by nontypeable Haemophilus influenzae (p = 0.001), TLR4 (p = 0.008) and TLR 9 (p = 0.018). The top five ranked individual transcripts from these pathways based on rank metric score are predominantly present in the NLR and TLR pathways, including IL1β (1.162), NLRP3 (1.135), IL1α (0.952), IL6 (0.931) and CCL4 (0.842). Gene set enrichment analyses implicate inflammasome-mediated and innate immune signaling pathways as key mediators of the development of PGD in lung transplant patients.

Vascular response to zotarolimus-coated balloons in injured superficial femoral arteries of the familial hypercholesterolemic Swine

BACKGROUND

Drug-coated balloons are rapidly emerging as a therapeutic alternative for the interventional treatment of peripheral vascular disease. The purpose of this study was to test the hypothesis that an angioplasty balloon coated with the mTOR inhibitor zotarolimus (ZCB) would inhibit neointimal hyperplasia in a novel injury-based superficial femoral artery model in the familial hypercholesterolemic swine.

METHODS AND RESULTS

A total of 44 familial hypercholesterolemic swine were included (12 designated to study tissue pharmacokinetics and 32 to study safety and efficacy). Fogarty balloon denudation was performed in all superficial femoral artery segments, followed by balloon angioplasty. In the pharmacokinetic study, a total of 24 ZCBs (300 μg/cm(2)) were used. Zotarolimus was detected in arterial tissue at 5 minutes (162 ng/mg of tissue), 24 hours (5.9 ng/mg of tissue), and 28 days (0.007 ng/mg of tissue) after ZCB inflation. In the safety and efficacy study, superficial femoral artery segments were randomized to either high-dose (600 μg/cm(2), n=16), low-dose (300 μg/cm(2), n=16), or paired uncoated balloons (high-dose ZCB control, n=16; low-dose ZCB control, n=16). At 28 days, the percentage of angiographic stenosis was similar among all tested groups. Histological analysis demonstrated a reduction in neointimal formation in both ZCB groups compared with controls (high-dose ZCB 44% reduction, P=0.007; low-dose ZCB 22% reduction, P=0.08). There was no evidence of delayed arterial healing or vascular toxicity in any of the ZCB groups.

CONCLUSIONS

The single delivery of zotarolimus via coated balloon is feasible, and therapeutic levels are maintained up to 28 days. The ZCB technology appears to be effective in the reduction of neointimal proliferation in the superficial femoral artery of the familial hypercholesterolemic swine.

Cardiomyocyte differentiation of bone marrow-derived Oct-4+CXCR4+SSEA-1+ very small embryonic-like stem cells

VSELs are a population of rare Oct-4+CXCR4+ CD133+lin-CD45- cells that are deposited during early embryogenesis in developing organs/tissues as a reserve population of pluripotent stem cells for regeneration. We reported recently that they are mobilized into peripheral blood during acute myocardial infarction (AMI) in mice and humans. However, although freshly isolated VSELs in experimental AMI mouse models improve cardiac function, the number of these cells is limited and an ex vivo expansion strategy is needed to employ these cells more efficiently for cardiac regeneration. The aim of this study was to establish an efficient method to expand ex vivo BM-derived very small embryonic-like stem cells (VSELs) into cardiomyocytes. VSELs, highly purified by FACS from the bone marrow of GFP transgenic mice, were expanded over C2C12 cell line myoblasts and exposed to cardiac differentiating media. The changes in gene expression during cardiac differentiation of VSELs were evaluated by RTQ-PCR, immunostaining and gene array analysis. We developed an efficient, two-step, ex vivo expansion/differentiation model of BM-derived VSELs into cardiomyocytes. First, purified GFP+ VSELs are plated over C2C12 murine cell line myoblasts, where they expand and differentiate into characteristic spheres. Subsequently, cells from these spheres are expanded on cardiac differentiating media into cardiomyocytes. This study demonstrates that murine BM-derived VSELs can be efficiently expanded in vitro and differentiated into cardiomyocytes.

Clinical Characteristics, Treatments, and Outcomes of Patients with Myocardial Infarction with Non-Obstructive Coronary Arteries (MINOCA): Results from a Multicenter National Registry

BACKGROUND

Diagnosis of myocardial infarction with non-obstructive coronary arteries (MINOCA) requires both clinical evidence of acute myocardial infarction (AMI) and demonstration of non-obstructive coronary arteries using angiography. We compared the clinical features, treatments, and three-year outcomes in patients with MINOCA and myocardial infarction with obstructive coronary artery disease (MI-CAD).

METHODS

We retrospectively analyzed data for 205,606 hospitalized patients with AMI. MINOCA was indicated as a working diagnosis in 6063 patients (2.94% of all AMI patients). For the control group we included 160,886 patients with MI-CAD. We evaluated the baseline characteristics, medication management options, outcomes, and readmission causes at 36 months follow-up.

RESULTS

Patients in the MINOCA group were younger. Females constituted a greater proportion of patients in the MINOCA group when compared to MI-CAD patients. STEMI during admission was diagnosed less frequently in the MINOCA group when compared to the MI-CAD group. All-cause mortality at 12 months was higher in the MINOCA group (10.94% vs. 9.54%, p < 0.001). At 36 months, there was no difference in the all-cause mortality rates (MINOCA 16.18% vs. MI-CAD 14.93%, p = 0.081). All-cause readmission rates were lower in the MINOCA group when compared to the MI-CAD group at both 12 months (45.19% vs. 54.33%, p < 0.001) and 36 months follow-up (56.42% vs. 66.66%, p < 0.001).

CONCLUSIONS

This is the first description of the clinical features, treatments, and three-year outcomes in a large population of Polish patients. The main finding of this study was a relatively low rate of MINOCA, with high rates of adverse events both at 12 and 36 months follow-up.

Induction of inducible nitric oxide synthase expression in ammonia-exposed cultured astrocytes is coupled to increased arginine transport by upregulated y(+)LAT2 transporter

One of the aspects of ammonia toxicity to brain cells is increased production of nitric oxide (NO) by NO synthases (NOSs). Previously we showed that ammonia increases arginine (Arg) uptake in cultured rat cortical astrocytes specifically via y(+)L amino acid transport system, by activation of its member, a heteromeric y(+)LAT2 transporter. Here, we tested the hypothesis that up-regulation of y(+)LAT2 underlies ammonia-dependent increase of NO production via inducible NOS (iNOS) induction, and protein nitration. Treatment of rat cortical astrocytes for 48 with 5 mM ammonium chloride ('ammonia') (i) increased the y(+)L-mediated Arg uptake, (ii) raised the expression of iNOS and endothelial NOS (eNOS), (iii) stimulated NO production, as manifested by increased nitrite+nitrate (Griess) and/or nitrite alone (chemiluminescence), and consequently, (iv) evoked nitration of tyrosine residues of proteins in astrocytes. Except for the increase of eNOS, all the above described effects of ammonia were abrogated by pre-treatment of astrocytes with either siRNA silencing of the Slc7a6 gene coding for y(+)LAT2 protein, or antibody to y(+)LAT2, indicating their strict coupling to y(+)LAT2 activity. Moreover, induction of y(+)LAT2 expression by ammonia was sensitive to Nf-κB inhibitor, BAY 11-7085, linking y(+)LAT2 upregulation to the Nf-κB activation in this experimental setting as reported earlier and here confirmed. Importantly, ammonia did not affect y(+)LAT2 expression nor y(+)L-mediated Arg uptake activity in the cultured cerebellar neurons, suggesting astroglia-specificity of the above described mechanism. The described coupling of up-regulation of y(+)LAT2 transporter with iNOS in ammonia-exposed astrocytes may be considered as a mechanism to ensure NO supply for protein nitration. Ammonia (NH4(+)) increases the expression and activity of the L-arginine (Arg) transporter (Arg/neutral amino acids [NAA] exchanger) y(+)LAT2 in cultured rat cortical astrocytes by a mechanism involving activation (nuclear translocation) of the transcription factor nuclear factor-Nuclear factor-κB (Nf-κB-p65). Up-regulation of y(+)LAT2 transporter is coupled with increased inducible nitric oxide synthase (iNOS) expression, which leads to increase nitric oxide (NO) synthesis and protein nitration.

Effects of intracoronary delivery of allogenic bone marrow-derived stem cells expressing heme oxygenase-1 on myocardial reperfusion injury

Heme oxygenase-1 (HO-1) decreases apoptosis, inflammation and oxidative stress. The aim of the study was to investigate the effects of intracoronary infusion of allogenic bone marrow cells (BMC) overexpressing HO-1 in the porcine model of myocardial infarction (MI). MI was produced by balloon occlusion of a coronary artery. BMC were transduced with adenoviruses encoding for HO-1 (HO-1 BMC) or GFP (GFP-BMC) genes. Prior to reperfusion animals received HO-1 BMC, control BMC (unmodified or GFP-BMC) or placebo. Left ventricular (LV) ejection fraction (EF), shortening fraction (SF), end-systolic and end-diastolic diameters (EDD, ESD) were assessed by echocardiography before, 30 minutes (min) and 14 days after reperfusion. BMC significantly improved LVEF and SF early (30 min) after reperfusion as well as after 14 days. Early after reperfusion HO-1 BMC were significantly more effective than control BMC, but after 14 days, there were no differences. There were no effect of cells on LV remodelling and diastolic function. Both HO-1 BMC and control BMC significantly reduced the infarct size vs. placebo (17.2 ± 2.7 and 18.8 ± 2.5, respectively, vs. 27.5 ± 5.1, p= 0.02) in histomorphometry. HO-1-positive donor BMC were detected in the infarct border area in pigs receiving HO-1-cells. No significant differences in expression of inflammatory genes (SDF-1, TNF-α, IL-6, miR21, miR29a and miR133a) in the myocardium were found. In conclusion, intracoronary delivery of allogeneic BMC immediately prior to reperfusion improved the LVEF and reduced the infarct size. HO-1 BMC were not superior to control cells after 14 days, however, produced faster recovery of LVEF. Transplanted cells survived in the peri-infarct zone.

Remote Supervision to Decrease Hospitalization Rate (RESULT) study in patients with implanted cardioverter-defibrillator

Aims

The number of patients with heart failure (HF) and implantable cardiac electronic devices has been growing steadily. Remote monitoring care (RC) of cardiac implantable electronic devices can facilitate patient-healthcare clinical interactions and prompt preventive activities to improve HF outcomes. However, studies that have investigated the efficacy of remote monitoring have shown mixed findings, with better results for the system including daily verification of transmission. The purpose of the RESULT study was to analyse the impact of remote monitoring on clinical outcomes in HF patients with implantable cardioverter-defibrillator [ICD/cardiac resynchronization therapy-defibrillator (CRT-D)] in real-life conditions.

Methods and results

The RESULT is a prospective, single-centre, randomized trial. Patients with HF and de novo ICD or CRT-D implantation were randomized to undergo RC vs. in-office follow-ups (SC, standard care). The primary endpoint was a composite of all-cause death and hospitalization due to cardiovascular reasons within 12 months after randomization. We randomly assigned 600 eligible patients (299 in RC vs. 301 in SC). Baseline clinical and echocardiographic characteristics were well-balanced and similar in both arms. The incidence of the primary endpoint differed significantly between RC and SC and involved 39.5% and 48.5% of patients, respectively, (P = 0.048) within the 12-month follow-up. The rate of all-cause mortality was similar between the studied groups (6% vs. 6%, P = 0.9), whereas hospitalization rate due to cardiovascular reasons was higher in SC (37.1% vs. 45.5%, P = 0.045).

Conclusion

Remote monitoring of HF patients with implanted ICD or CRT-D significantly reduced the primary endpoint rate, mostly as a result of a lower hospitalization rate in the RC arm (ClinicalTrials.gov Identifier: NCT02409225).

The dimethylarginine (ADMA)/nitric oxide pathway in the brain and periphery of rats with thioacetamide-induced acute liver failure: Modulation by histidine

Hepatic encephalopathy (HE) is related to variations in the nitric oxide (NO) synthesis and oxidative/nitrosative stress (ONS), and asymmetric dimethylarginine (ADMA) is an endogenous inhibitor of nitric oxide synthases (NOSs). In the present study we compared the effects of acute liver failure (ALF) in the rat TAA model on ADMA concentration in plasma and cerebral cortex, and on the activity and expression of the ADMA degrading enzyme, dimethylarginine dimethylaminohydrolase (DDAH), in brain and liver. ALF increased blood and brain ADMA, and the increase was correlated with decreased DDAH activity in both brain and liver. An i.p. administration of histidine (His), an amino acid reported to alleviate oxidative stress associated with HE (100 mg/kg b.w.), reversed the increase of brain ADMA, which was accompanied by the recovery of brain DDAH activity (determined ex vivo), and with an increase of the total NOS activity. His also activated DDAH ex vivo in brain homogenates derived from control and TAA rats. ALF in this model was also accompanied by increases of blood cyclooxygenase activity and blood and brain TNF-α content, markers of the inflammatory response in the periphery, but these changes were not affected by His, except for the reduction of TNF-α mRNA transcript in the brain. His increased the total antioxidant capacity of the brain cortex, but not of the blood, further documenting its direct neuroprotective power.

Comparable vascular response of a new generation sirolimus eluting stents when compared to fluoropolymer everolimus eluting stents in the porcine coronary restenosis model

BACKGROUND

Novel sirolimus eluting stents (SES) have shown non-inferior clinical outcomes when compared to everolimus eluting stents (EES), however only limited preclinical data have been published. Therefore, we evaluate vascular response of a new generation biodegradable polymer SES (BP-SES: Alex Plus, Balton) and fluoropolymer EES (EES: Xience Pro, Abbott) in the porcine coronary restenosis model.

METHODS

A total of 40 stents were implanted with 120% overstretch in coronaries of 17 domestic swine: 16 BP-SES, 16 EES and 8 bare metal controls (BMS). Following 28 and 90 days, coronary angiography and optical coherence tomography (OCT) was performed, animals sacrificed and stented segments harvested for pathological evaluation.

RESULTS

At 28 days neointimal thickness in OCT was lowest in the BP-SES when compared to EES and BMS (0.18 ± 0.1 vs. 0.39 ± 0.1 vs. 0.34 ± 0.2 mm, respectively; p = 0.04). There was no difference in the proportion of malapposed or uncovered struts, although protruding covered struts were more common in BP-SES (14.8 ± 10% vs. 4.1 ± 4% vs. 3.7 ± 6%; p = 0.03). In pathology, the lowest neointimal thickness was confirmed in BP-SES (p < 0.05). The inflammation score was significantly lower in BP-SES and EES when compared to BMS (0.24 ± 0.1 vs. 0.4 ± 0.1 vs. 0.77 ± 0.4; p < 0.01) whilst EES and BP-SES had higher fibrin scores than BMS (1.2 ± 0.4 vs. 1.3 ± 0.3 vs. 0.17 ± 0.2; p < 0.01). At 90 days neointimal coverage and thickness in OCT was comparable between groups and healing in histopathology was complete.

CONCLUSIONS

New generation, BP-SES show similar vascular healing and biocompatibility profile with marginally higher degree of restenosis inhibition, when compared to fluoropolymer EES in the porcine coronary restenosis model.

Experimental evaluation of efficacy and healing response of everolimus-eluting stents in the familial hypercholesterolemic swine model: a comparative study of bioabsorbable versus durable polymer stent platforms

BACKGROUND

The utility of animal models for the prediction of drug-eluting stent (DES) efficacy in human clinical trials is still unclear. The familial hypercholesterolemic swine (FHS) model has been shown to induce a human-like neointimal response to bare metal stent (BMS) implantation. However, its utility to discriminate efficacy signals following DES implantation is unknown. In this study, we aimed to test the efficacy and healing response of several everolimus-eluting stent (EES) platforms in the coronary territory of the FHS.

METHODS

A total of 19 EES platforms (SYNERGY=6, SYNERGY½-dose=7, and PROMUS Element=6) and an identical BMS control (Element=6) were implanted into the coronary arteries of nine FHS. All implants were performed under intravascular ultrasound guidance using a 1.2 : 1 overstretch ratio. At 30 days, the vascular response to the implant was evaluated by quantitative coronary angiography, optical coherence tomography, and histology.

RESULTS

At 28 days, all EES platforms showed a significant decrease in angiographic late lumen loss (between 27 and 37%) compared with the BMS control group. This finding was confirmed both by optical coherence tomography (mean neointimal thickness=28-42% reduction) and by histology (mean neointimal thickness=44-55% reduction). All EES platforms showed similar degrees of neointimal inhibition. The presence of moderate to severe para-strut inflammation was observed in 83% of the stent sections in the BMS group compared with 28.6% in the SYNERGY½-dose group and 0% in the SYNERGY and PROMUS groups (P=0.0002). There was a 68-95% reduction in MMP9 expression in the media in all EES platforms compared with the BMS controls. The presence of mild to moderate para-strut fibrin deposits ranged from 66.7 to 83.4% in all EES platforms compared with 16.7% in the EBMS group.

CONCLUSION

The FHS coronary injury model showed the efficacy of several EES platforms compared with an identical BMS control. Everolimus eluted from different polymeric platforms showed lower levels of inflammation and slightly higher fibrin deposits compared with BMS controls.

TNFα increases STAT3-mediated expression of glutaminase isoform KGA in cultured rat astrocytes

Glutamate related excitotoxicity and excess of cerebral levels of tumor necrosis factor alpha (TNFα) are interrelated and well documented abnormalities noticed in many central nervous system diseases. Contribution of kidney type glutaminase (KGA) and shorter alternative splicing form (GAC) to glutamine degradation in astrocytes has been recently a matter of dispute and extensive study but the regulation of the GLS isoforms by inflammatory factors is still not well known. Here we show that treatment of cultured rat cortical astrocytes with pathophysiologically relevant (50 ng/ml) concentration of TNFα specifically increases the expression of KGA but not GAC and increases activity of GLS. No changes in the expression of either of two GLS isoforms were observed following treatment with other tested cytokines IL-1β and IL-6. The TNFα mediated KGA expression was associated with increased phosphorylation of signal transducer and activator of transcription 3 (STAT3). Stimulatory effect of TNF-α on KGA expression was reduced by selective inhibition of (STAT3) but not by inhibition of STAT1 nor nuclear transcription factor kappa. Additionally, the role of miRNA in TNFα-induced expression of KGA in astrocytes was excluded, since the expression of miR-23a/b and miR-200c, potential regulators of KGA expression, was unchanged. This study documents increased KGA expression in the astrocytes under inflammatory stimulation, identifying TNFα as a cytokine mediating this response, and demonstrates the specific and selective involvement of STAT3.