Circulating MicroRNA-122-5p Is Associated With a Lack of Improvement in Left Ventricular Function After Transcatheter Aortic Valve Replacement and Regulates Viability of Cardiomyocytes Through Extracellular Vesicles.

BACKGROUND: Transcatheter aortic valve replacement (TAVR) is a well-established treatment option for high- and intermediate-risk patients with severe symptomatic aortic valve stenosis. A majority of patients exhibit improvements in left ventricular ejection fraction (LVEF) after TAVR in response to TAVR-associated afterload reduction. However, a specific role for circulating microRNAs (miRNAs) in the improvement of cardiac function for patients after TAVR has not yet been investigated. Here, we profiled the differential expression of miRNAs in circulating extracellular vesicles (EVs) in patients after TAVR and, in particular, the novel role of circulating miR-122-5p in cardiomyocytes. METHODS: Circulating EV-associated miRNAs were investigated by use of an unbiased Taqman-based human miRNA array. Several EV miRNAs (miR-122-5p, miR-26a, miR-192, miR-483-5p, miR-720, miR-885-5p, and miR-1274) were significantly deregulated in patients with aortic valve stenosis at day 7 after TAVR compared with the preprocedural levels in patients without LVEF improvement. The higher levels of miR-122-5p were negatively correlated with LVEF improvement at both day 7 (r=-0.264 and P=0.015) and 6 months (r=-0.328 and P=0.0018) after TAVR. RESULTS: Using of patient-derived samples and a murine aortic valve stenosis model, we observed that the expression of miR-122-5p correlates negatively with cardiac function, which is associated with LVEF. Mice with graded wire injury-induced aortic valve stenosis demonstrated a higher level of miR-122-5p, which was related to cardiomyocyte dysfunction. Murine ex vivo experiments revealed that miR-122-5p is highly enriched in endothelial cells compared with cardiomyocytes. Coculture experiments, copy-number analysis, and fluorescence microscopy with Cy3-labeled miR-122-5p demonstrated that miR-122-5p can be shuttled through large EVs from endothelial cells into cardiomyocytes. Gain- and loss-of-function experiments suggested that EV-mediated shuttling of miR-122-5p increases the level of miR-122-5p in recipient cardiomyocytes. Mechanistically, mass spectrometry, miRNA pulldown, electrophoretic mobility shift assay, and RNA immunoprecipitation experiments confirmed that miR-122-5p interacts with the RNA-binding protein hnRNPU (heterogeneous nuclear ribonucleoprotein U) in a sequence-specific manner to encapsulate miR-122-5p into large EVs. On shuttling, miR-122-5p reduces the expression of the antiapoptotic gene BCL2 by binding to its 3' untranslated region to inhibit its translation, thereby decreasing the viability of target cardiomyocytes. CONCLUSIONS: Increased levels of circulating proapoptotic EV-incorporated miR-122-5p are associated with reduced LVEF after TAVR. EV shuttling of miR-122-5p regulates the viability and apoptosis of cardiomyocytes in a BCL2-dependent manner.

Toll-like receptor-3 contributes to the development of aortic valve stenosis.

Aortic valve stenosis (AS) development is driven by distinct molecular and cellular mechanisms which include inflammatory pathways. Toll-like-receptor-3 (TLR3) is a lysosomal pattern-recognition receptor that binds double-stranded RNA and promotes pro-inflammatory cellular responses. In recent years, TLR3 has emerged as a major regulator of vascular inflammation. The exact role of TLR3 in the development of AS has not been investigated. Isolated human valvular interstitial cells (VICs) were stimulated with the TLR3-agonist polyIC and the resulting pro-inflammatory and pro-osteogenic response measured. Severe AS was induced in wildtype- and TLR3-/- mice via mechanical injury of the aortic valve with a coronary springwire. TLR3 activation was achieved by polyIC injection every 24 h after wire injury, while TLR3 inhibition was realized using Compound 4a (C4a) every 48 h after surgery. Endothelial mesenchymal transition (EndoMT) of human valvular endothelial cells (VECs) was assessed after polyIC stimulation. Stimulation of human VICs with polyIC promoted a strong inflammatory and pro-osteogenic reaction. Similarly, injection of polyIC marginally increased AS development in mice after wire injury. AS induction was significantly decreased in TLR3-/- mice, confirming the role of endogenous TLR3 ligands in AS pathology. Pharmacological inhibition of TLR3 with C4a not only prevented the upregulation of inflammatory cytokines and osteogenic markers in VICs, and EndoMT in VECs, but also significantly abolished the development of AS in vivo. Endogenous TLR3 activation significantly contributes to AS development in mice. Pharmacological inhibition of TLR3 with C4a prevented AS formation. Therefore, targeting TLR3 may be a viable treatment option.

Ceramide Metabolism in Cardiovascular Disease: A Network With High Therapeutic Potential.

Growing evidence suggests that ceramides play an important role in the development of atherosclerotic and valvular heart disease. Ceramides are biologically active sphingolipids that are produced by a complex network of enzymes. Lowering cellular and tissue levels of ceramide by inhibiting the ceramide-producing enzymes counteracts atherosclerotic and valvular heart disease development in animal models. In vascular tissues, ceramides are produced in response to hyperglycemia and TNF (tumor necrosis factor)-α signaling and are involved in NO-signaling and inflammation. In humans, elevated blood ceramide levels are associated with cardiovascular events. Furthermore, important cardiovascular risk factors, such as obesity and diabetes, have been linked to ceramide accumulation. This review summarizes the basic mechanisms of how ceramides drive cardiovascular disease locally and links these findings to the intriguing results of human studies on ceramides as biomarkers for cardiovascular events. Moreover, we discuss the current state of interventions to therapeutically influence vascular ceramide metabolism, both locally and systemically.

Analysis of circulating ceramides and hexosylceramides in patients with coronary artery disease and type II diabetes mellitus.

BACKGROUND: Cardiovascular disease (CVD) remains the leading cause of death worldwide. The main driving force behind this association is coronary artery disease (CAD), the manifestation of atherosclerosis in the coronary circulation. Cornerstones in the development of CAD are pathologies in lipid metabolism. In recent years, ongoing research has identified ceramides, a subclass of sphingolipids to be mediators of CVD. The aim of this study is to investigate the influence of type II diabetes mellitus (DM) on circulating ceramides and hexosylceramides (HexCers) in CAD patients. METHODS: 24 patients aged 40-90 years with CAD confirmed by angiography were included into a pilot study. Patients with DM were identified by analysis of discharge letters or other medical documents available at the study center. During coronary angiography, arterial blood samples were collected and quantification of sphingolipids in patient serum was performed by mass spectrometry. RESULTS: Statistical analysis showed nine significantly different HexCers in CAD patients with DM compared to patients without DM. Among the nine significantly regulated HexCers, we identified seven d18:1 HexCers. This group contributes to the fourth most abundant subgroup of total ceramides and HexCers in this dataset. HexCer-d18:1-23:1(2-OH) showed the strongest downregulation in the patient group with DM. CONCLUSION: This study suggests that levels of circulating HexCers are downregulated in patients with CAD and concomitant DM compared to patients without DM. Further research is needed to investigate the underlying mechanisms and the suitability of HexCers as possible mediators and/or prognostic markers in CAD.

Activation of neutral sphingomyelinase 2 through hyperglycemia contributes to endothelial apoptosis via vesicle-bound intercellular transfer of ceramides.

BACKGROUND: Pro-apoptotic and pro-inflammatory ceramides are crucially involved in atherosclerotic plaque development. Local cellular ceramide accumulation mediates endothelial apoptosis, especially in type 2 diabetes mellitus, which is a major cardiovascular risk factor. In recent years, large extracellular vesicles (lEVs) have been identified as an important means of intercellular communication and as regulators of cardiovascular health and disease. A potential role for lEVs as vehicles for ceramide transfer and inductors of diabetes-associated endothelial apoptosis has never been investigated. METHODS AND RESULTS: A mass-spectrometric analysis of human coronary artery endothelial cells (HCAECs) and their lEVs revealed C16 ceramide (d18:1-16:0) to be the most abundant ceramide in lEVs and to be significantly increased in lEVs after hyperglycemic injury to HCAECs. The increased packaging of ceramide into lEVs after hyperglycemic injury was shown to be dependent on neutral sphingomyelinase 2 (nSMase2), which was upregulated in glucose-treated HCAECs. lEVs from hyperglycemic HCAECs induced apoptosis in the recipient HCAECs compared to native lEVs from untreated HCAECs. Similarly, lEVs from hyperglycemic mice after streptozotocin injection induced higher rates of apoptosis in murine endothelial cells compared to lEVs from normoglycemic mice. To generate lEVs with high levels of C16 ceramide, ceramide was applied exogenously and shown to be effectively packaged into the lEVs, which then induced apoptosis in lEV-recipient HCAECs via activation of caspase 3. Intercellular transfer of ceramide through lEVs was confirmed by use of a fluorescently labeled ceramide analogue. Treatment of HCAECs with a pharmacological inhibitor of nSMases (GW4869) or siRNA-mediated downregulation of nSMase2 abrogated the glucose-mediated effect on apoptosis in lEV-recipient cells. In contrast, for small EVs (sEVs), hyperglycemic injury or GW4869 treatment had no effect on apoptosis induction in sEV-recipient cells. CONCLUSION: lEVs mediate the induction of apoptosis in endothelial cells in response to hyperglycemic injury through intercellular transfer of ceramides.

Atherosclerotic Conditions Promote the Packaging of Functional MicroRNA-92a-3p Into Endothelial Microvesicles.

RATIONALE: Microvesicle-incorporated microRNAs (miRs) are biomarkers and effectors of cardiovascular disease. Whether microvesicle-miR expression is regulated in coronary artery disease (CAD) or not is unknown. OBJECTIVE: Here, we explore the expression of circulating microvesicle-miRs in patients with CAD and investigate the role of microvesicle-miR in endothelial cells. METHODS AND RESULTS: Circulating microvesicles were isolated from patients' plasma by using ultracentrifugation. Electron microscopy was used to determine the size of the microvesicles. A Taqman miR array revealed certain microvesicle-miRs are significantly regulated in patients with stable CAD compared with patients with ACS. To validate the miR array results, 180 patients with angiographically excluded CAD (n=41), stable CAD (n=77), and acute coronary syndrome (n=62) were prospectively studied. Nine miRs involved in regulation of vascular performance-miR-126-3p, miR-222-3p, miR-let-7d-5p, miR-21-5p, miR-26a-5p, miR-92a-3p, miR-139-5p, miR-30b-5p, and miR-199a-5p-were quantified in circulating microvesicles by real-time polymerase chain reaction (PCR). Among these, miR-92a-3p was significantly increased in patients with CAD compared with non-CAD patients. Microvesicle-sorting experiments showed endothelial cells (ECs) were the major cell source for microvesicles containing miR-92a-3p. In vitro oxLDL (oxidized low-density lipoprotein) and IL-6 (interleukin-6) stimulation increased miR-92a-3p expression in parent ECs and upregulated the expression level of endothelial microvesicle (EMV)-incorporated miR-92a-3p. Labeling of miR-92a-3p and EMVs demonstrated that functional miR-92a-3p was transported into recipient ECs, which accelerated cell migration and proliferation. Knockdown of miR-92a-3p in EMVs abrogated EMV-mediated effects on EC migration, proliferation, and blocked vascular network formation in a matrigel plug. Polymerase chain reaction-based gene profiling showed that the expression of THBS1 (thrombospondin 1) protein-a target of miR-92a-3p and an inhibitor of angiogenesis-was significantly reduced in ECs by EMVs. Knockdown of miR-92a-3p in EMVs abrogated EMV-mediated inhibition of the THBS1 gene and protein expression. CONCLUSIONS: Atherosclerotic conditions promote the packaging of endothelial miR-92a-3p into EMVs. EMV-mediated transfer of functional miR-92a-3p regulates angiogenesis in recipient ECs by a THBS1-dependent mechanism.

Aortic Valve Stenosis: From Basic Mechanisms to Novel Therapeutic Targets.

Aortic valve stenosis is the most prevalent heart valve disease worldwide. Although interventional treatment options have rapidly improved in recent years, symptomatic aortic valve stenosis is still associated with high morbidity and mortality. Calcific aortic valve stenosis is characterized by a progressive fibro-calcific remodeling and thickening of the aortic valve cusps, which subsequently leads to valve obstruction. The underlying pathophysiology is complex and involves endothelial dysfunction, immune cell infiltration, myofibroblastic and osteoblastic differentiation, and, subsequently, calcification. To date, no pharmacotherapy has been established to prevent aortic valve calcification. However, novel promising therapeutic targets have been recently identified. This review summarizes the current knowledge of pathomechanisms involved in aortic valve calcification and points out novel treatment strategies.

Murine sca1/flk1-positive cells are not endothelial progenitor cells, but B2 lymphocytes.

Circulating sca1+/flk1+ cells are hypothesized to be endothelial progenitor cells (EPCs) in mice that contribute to atheroprotection by replacing dysfunctional endothelial cells. Decreased numbers of circulating sca1+/flk1+ cells correlate with increased atherosclerotic lesions and impaired reendothelialization upon electric injury of the common carotid artery. However, legitimate doubts remain about the identity of the putative EPCs and their contribution to endothelial restoration. Hence, our study aimed to establish a phenotype for sca1+/flk1+ cells to gain a better understanding of their role in atherosclerotic disease. In wild-type mice, sca1+/flk1+ cells were mobilized into the peripheral circulation by granulocyte-colony stimulating factor (G-CSF) treatment and this movement correlated with improved endothelial regeneration upon carotid artery injury. Multicolor flow cytometry analysis revealed that sca1+/flk1+ cells predominantly co-expressed surface markers of conventional B cells (B2 cells). In RAG2-deficient mice and upon B2 cell depletion, sca1+/flk1+ cells were fully depleted. In the absence of monocytes, sca1+/flk1+ cell levels were unchanged. A PCR array focused on cell surface markers and next-generation sequencing (NGS) of purified sca1+/flk1+ cells confirmed their phenotype to be predominantly that of B cells. Finally, the depletion of B2 cells, including sca1+/flk1+ cells, in G-CSF-treated wild-type mice partly abolished the endothelial regenerating effect of G-CSF, indicating an atheroprotective role for sca1+/flk1+ B2 cells. In summary, we characterized sca1+/flk1+ cells as a subset of predominantly B2 cells, which are apparently involved in endothelial regeneration.

Endothelial microparticle-promoted inhibition of vascular remodeling is abrogated under hyperglycaemic conditions.

BACKGROUND: Endothelial microparticles (EMPs) inhibit vascular remodeling by transferring functional microRNA (miRNA) into target vascular smooth muscle cells (VSMCs). Because EMPs are increased in diabetic patients and potentially linked to vascular complications in diabetes mellitus, we sought to determine whether effects of EMPs generated under high glucose concentration on vascular remodeling might differ from EMPs derived from untreated cells. METHODS AND RESULTS: EMPs were generated from human coronary endothelial cells (HCAEC) exposed to high glucose concentrations in order to mimic diabetic conditions. These EMPs were defined as 'hyperglycaemic' EMPs (hgEMPs) and their miRNA transfer capacity and functional effects were compared with EMPs generated from 'healthy' untreated HCAECs. In vitro, the intercellular transfer of antiproliferative miRNA-126-3p from ECs to VSMCs via EMPs was significantly reduced under hyperglycaemic conditions. Additionally, EMP-mediated inhibition of the miRNA-126-3p target LRP6 and of VSMC migration and proliferation was abrogated, when hgEMPs were used. In vivo, the inhibitory effect of EMPs on neointima formation, VSMC proliferation and macrophage infiltration was abolished in mice treated with hgEMPs. CONCLUSION: Pathological hyperglycaemic conditions weaken potentially protective intercellular communication mechanisms by affecting EMP content and function.

Long-term individual shear rate therapy counterpulsation enhances plasma nitrite release in patients with PAD.

BACKGROUND: Individual shear rate therapy (ISRT) has been designed as a novel non-invasive treatment option for peripheral artery disease (PAD) patients and has been shown to improve endothelial function and walking distance. The aim of this study was to elucidate the impact of ISRT on the level of nitric oxide in patient blood plasma and the expression of related molecular markers in peripheral blood mononuclear cells (PBMCs). Molecular diagnostic tests were performed for two ISRT trials. PATIENTS AND METHODS: In ISRT-1 26 healthy subjects underwent one session of treadmill training and one session of ISRT respectively in a cross-over design. In ISRT-2 14 PAD patients with a stable intermittent claudication underwent a 30 hours long-term treatment. Plasma nitrite release as well as the mRNA expression of NOS2 and key regulators of the kallikrein-kinin system were measured in PBMCs at different time points. RESULTS: Short-term ISRT revealed significantly decreased NOS2 expression in PBMCs of healthy volunteers and PAD patients. Long-term ISRT, in turn, demonstrated a significant plasma nitrite increase in PAD patients. CONCLUSIONS: We verified that long-term ISRT stimulates the vascular system and exerts a comparable effect to physical exercise in regards to NO release, which coincide with recent findings regarding an improvement of endothelial function. However, further studies are necessary to investigate the role for circulating leukocytes.
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Adaptation of external counterpulsation based on individual shear rate therapy improves endothelial function and claudication distance in peripheral artery disease.

BACKGROUND: External counterpulsation therapy enhances blood flow and was shown to improve endothelial function and quality of life in coronary artery disease patients. However, high pressures of up to 300 mmHg may lead to malperfusion of the ischaemic limb. To improve the clinical outcome of patients with peripheral artery disease (PAD), we adjusted external counterpulsation and developed a novel non-invasive approach termed individual shear rate therapy (ISRT). PATIENTS AND METHODS: In the present study, 14 patients with a Fontaine stage IIb and femoral-popliteal PAD underwent 30 hours of ISRT over 5 weeks. For ISRT, individual treatment pressures that do not exceed 160 mmHg were assessed by Doppler flow parameters during counterpulsation (individual shear rate diagnosis) in order to enhance and maximise peripheral perfusion. The study aimed to enhance peripheral perfusion and evaluate the primary clinical endpoint endothelial function, as well as to perform preliminary analysis of the ankle brachial index (ABI) and walking distance. RESULTS: Doppler flow measurements in the lower limb (ankle) validated that maximum blood flow velocity during systole and acceleration doubled during ISRT. Study results demonstrated that long-term ISRT significantly increased flow-mediated dilation (FMD) in the brachial artery (0.13+/- 0.09 mm to 0.38+/- 0.05 mm; p < 0.05), while nitromediated dilation (0.36+/- 0.10 mm to 0.45+/- 0.08 mm) remained and common femoral artery FMD did not reach statistical significance (0.38+/- 0.08 mm to 0.67+/- 0.19 mm; p<0.05). Initial claudication distance considerably improved for all patients after 30 hours of ISRT (92.6 +/- 8.2 metres to 280+/- 101.3 metres, p<0.05), just like the absolute claudication distance, which showed a more than 2.5-fold increase (167.8+/- 18.1 metres to 446.7+/- 133.3 metres; p<0.05). The ABI did not improve (0.58+/- 0.03 to 0.65+/- 0.04). CONCLUSIONS: Our data demonstrate that long-term ISRT is a potential novel non-invasive treatment to improve endothelial function and absolute pain-free walking distance for PAD patients.

Comparison of Arctic Front Advance Pro and POLARx cryoballoons for ablation therapy of atrial fibrillation: an intraprocedural analysis.

INTRODUCTION: Cryoballoon (CB) ablation has become a popular method for pulmonary vein isolation (PVI) in atrial fibrillation (AF) treatment. This study aimed to compare the intraprocedural ablation characteristics of two cryoballoons, Arctic Front Advance Pro™ (AFA-Pro, Medtronic) and POLARx™ (Boston Scientific). METHODS AND RESULTS: In this retrospective single-center study, 230 symptomatic paroxysmal or persistent AF patients underwent CB ablation with either AFA-Pro or POLARx. Propensity-score matching resulted in two cohorts of 114 patients each. Baseline and procedural characteristics were comparable between both CBs. POLARx achieved lower minimal temperatures (e.g., left superior pulmonary vein, LSPV: AFA-Pro - 49.0 °C vs. POLARx - 59.5 °C) and lower temperatures at time-to-isolation (TTI). Additionally, POLARx reached lower temperatures faster, as evidenced by lower temperatures after 40 and 60 s, and a larger mean temperature change between 20 and 40 s. POLARx also had a greater area under the curve below 0 °C and a longer thawing phase. Both CBs achieved comparable high rates of final PV-isolation. TTI, minimal esophagus temperature, and first-pass isolation rates were similar between groups. Periprocedural complications, including phrenic nerve injuries, were comparable. Troponin levels in the left atrium were elevated with both systems. Values and change in troponin were numerically higher in the POLARx group (delta troponin: AFA-Pro 36.3 (26.4, 125.4) ng/L vs. POLARx 104.9 (49.5, 122.2) ng/L), p = 0.077). CONCLUSION: AFA-Pro and POLARx are both highly effective and safe CB systems for PVI. POLARx exhibited significant faster and lower freezing characteristics, and numerically higher troponin levels might indicate greater myocardial injury. However, these differences did not translate into improved performance, procedural efficiency, or safety.

Loss of ceramide synthase 5 inhibits the development of experimentally induced aortic valve stenosis.

AIM: Inflammation and calcification are hallmarks in the development of aortic valve stenosis (AVS). Ceramides mediate inflammation and calcification in the vascular tissue. The highly abundant d18:1,16:0 ceramide (C16) has been linked to increased cardiovascular mortality and obesity. In this study, we investigate the role of ceramide synthase 5 (CerS5), a critical enzyme for C16 ceramide synthesis, in the development of AVS, particularly in conjunction with a high-fat/high-cholesterol diet (Western diet, WD). METHODS: We used wild-type (WT) and CerS5-/- mice on WD or normal chow in a wire injury model. We measured the peak velocity to determine AVS development and performed histological analysis of the aortic valve area, immune cell infiltration (CD68 staining), and calcification (von Kossa). In vitro experiments involved measuring the calcification of human aortic valvular interstitial cells (VICs) and evaluating cytokine release from THP-1 cells, a human leukemia monocytic-like cell line, following CerS5 knockdown. RESULTS: CerS5-/- mice showed a reduced peak velocity compared to WT only in the experiment with WD. Likewise, we observed reduced immune cell infiltration and calcification in the aortic valve of CerS5-/- mice, but only on WD. In vitro, calcification was reduced after knockdown of CerS5 in VICs, while THP-1 cells exhibited a decreased inflammatory response following CerS5 knockdown. CONCLUSION: We conclude that CerS5 is an important mediator for the development of AVS in mice on WD and regulates critical pathophysiological hallmarks of AVS formation. CerS5 is therefore an interesting target for pharmacological therapy and merits further investigation.

Impact of transradial versus transfemoral access for preprocedural coronary angiography on TAVR-associated complications.

Background: Vascular injury and bleeding complications remain frequent after transcatheter aortic valve replacement (TAVR). Whether the access-site of preprocedural coronary angiography (CAG) affects TAVR-related complications is not known. The aim of this study was to evaluate the impact of transradial (TRA) versus transfemoral access (TFA) for preprocedural CAG on outcomes in patients undergoing subsequent TAVR. Methods: The study cohort included 1002 patients undergoing transfemoral TAVR, of whom 39.4% (395/1002) had undergone radial and 60.6% (607/1002) femoral access for pre-TAVR CAG. The primary endpoint was a composite of 30-day mortality and major vascular complications after TAVR. Key secondary endpoints included VARC-3-defined complications. Results: The primary endpoint occurred less frequently in patients with prior TRA (3.3%) as compared to patients with prior TFA (6.3%, p = 0.04), which was mainly driven by significantly lower rates of major vascular complications (0.8% vs 2.5%, p = 0.05). Moreover, incidences of periprocedural access-related vascular injury and unplanned endovascular interventions were lower in TRA patients (13.2% vs 18.0%, p = 0.05). The rate of major bleeding tended to be lower in the TRA (1.5%) as compared to the TFA group (3.5%) but was not significantly different (p = 0.07). Moreover, the rate of life-threatening bleeding was comparable between both groups (0.5% vs 0.8%, p = 0.71). Conclusion: Transradial access for preprocedural CAG was associated with significantly lower rates of vascular complications following subsequent TAVR as compared to transfemoral access. However, despite the tendency to lower major bleedings with transradial access, no significant association was detectable between the access-site of coronary angiography and TAVR-related bleeding complications.

A prospective, randomized, controlled, multicentre trial for secondary prevention in patients with chronic coronary syndrome using a smartphone application for digital therapy: the CHANGE study protocol.

Aims: Coronary artery disease (CAD) remains the leading cause of death worldwide. 'Stable' CAD is a chronic progressive condition, which recent European guidelines recommend referring to as 'chronic coronary syndrome' (CCS). Despite therapeutic advances, morbidity and mortality among patients with CCS remain high. Optimal secondary prevention in patients with CCS includes optimization of modifiable risk factors with behavioural changes and pharmacological therapy. The CHANGE study aims to provide evidence for optimization of secondary prevention in CCS patients by using a smartphone application (app). Methods and results: The CHANGE study is designed as a prospective, randomized, controlled trial with a 1:1 allocation ratio, which is currently performed in nine centres in Germany in a parallel group design. 210 patients with CCS will be randomly allocated either to the control group (standard-of-care) or to the intervention group, who will be provided the VantisTherapy* app in addition to standard-of-care to incorporate secondary prevention into their daily life. The study will be performed in an open design. Outcomes will be assessed using objective data from three in-person visits (0, 12, and 24 weeks). Primary outcomes will involve adherence to secondary prevention recommendations and quality of life (QoL). The recruitment process started in July 2022. Conclusion: The CHANGE study will investigate whether a smartphone-guided secondary prevention app, combined with a monitor function compared with standard-of-care, has beneficial effects on overall adherence to secondary prevention guidelines and QoL in patients with CCS. Trial registration: The study is listed at the German study registry (DRKS) under the registered number DRKS00028081.

Optimal protamine-to-heparin dosing ratio for the prevention of bleeding complications in patients undergoing TAVR-A multicenter experience.

BACKGROUND: Despite major advances, transcatheter aortic valve replacement (TAVR) is still associated with procedure-specific complications. Although previous studies reported lower bleeding rates in patients receiving protamine for heparin reversal, the optimal protamine-to-heparin dosing ratio is unknown. HYPOTHESIS: The aim of this study was a comparison of two different heparin antagonization regimens for the prevention of bleeding complications after TAVR. METHODS: The study included 1446 patients undergoing TAVR, of whom 623 received partial and 823 full heparin antagonization. The primary endpoint was a composite of 30-day mortality, life-threatening, and major bleeding. Safety endpoints included stroke and myocardial infarction at 30 days. RESULTS: Full antagonization of heparin resulted in lower rates of the primary endpoint as compared to partial heparin reversal (5.6% vs. 10.4%, p < .01), which was mainly driven by lower rates of life-threatening (0.5% vs. 1.6%, p = .05) and major bleeding (3.2% vs. 7.5%, p < .01). Moreover, the incidence of major vascular complications was significantly lower in patients with full heparin reversal (3.5% vs. 7.5%, p < .01). The need for red-blood-cell transfusion was lower in patients receiving full as compared to partial heparin antagonization (10.4% vs. 15.9%, p < .01). No differences were observed in the incidence of stroke and myocardial infarction between patients with full and partial heparin reversal (2.2% vs. 2.6%, p = .73 and 0.2% vs. 0.4%, p = .64, respectively). CONCLUSIONS: Full heparin antagonization resulted in significantly lower rates of life-threatening and major bleeding after TAVR as compared to partial heparin reversal. The occurrence of stroke and myocardial infarction was low and comparable between both groups.

Transverse aortic constriction-induced heart failure leads to increased levels of circulating microparticles.

BACKGROUND: Circulating microparticles represent one type of signal transmission between cells. Previous studies revealed increased levels of circulating microparticles in patients with heart failure, while composition, temporal occurrence and biological effects are largely unknown. METHODS: Circulating microparticles were quantified by flow cytometry in mice following TAC. Microparticles were characterized by NTA and immunoblotting for Flotillin-1. Microparticle content was investigated by microRNA analyses. RESULTS: After TAC induction of heart failure could be demonstrated. Simultaneously we observed increased numbers of circulating microparticles in the first week after TAC with a rapid decline thereafter. The most relevant fraction of circulating EVs after TAC derived from lymphocytes containing has-miR-26a-5p and / -146b-5p known to be involved in inflammatory processes. CONCLUSION: This work provides a previously unknown timely limited occurrence of circulating microparticles after new onset of heart failure which might have important influence on disease development and progression and thereby are of probable therapeutic relevance.

Analysis of nocturnal, hypoxia-induced miRNAs in sleep apnea patients.

INTRODUCTION: Obstructive sleep apnea syndrome (OSAS) is associated with an increased cardiovascular risk. The underlying mechanisms are largely unclear. MicroRNAs (miRNAs) are RNAs circulating in the blood that can be released into the bloodstream during hypoxia. In the present study, we investigate if OSAS-induced hypoxia results in a release of miRNAs that may mediate OSAS-associated cardiovascular damage. METHODS: Blood was sampled from 23 OSAS patients before and after a polygraphically monitored night. Total circulating RNA was isolated from the plasma and quantified using real-time qPCR. Using a Taqman miRNA array, the levels of 384 different miRNAs were compared between evening and morning after polysomnography. The most highly upregulated miRNA (miRNA-505) and four additionally upregulated miRNAs (miRNA-127, miRNA-133a, miRNA-145, and miRNA-181a) were then quantified in a bigger patient cohort individually. RESULTS: Apnea/Hypopnea-Index (AHI) was evaluated and averaged at 26 per hour on nocturnal polygraphy. In an initial miRNA array, a total of 4 miRNAs were significantly regulated. A significant increase of miRNA-145 was observed in the larger patient cohort. No significant changes in concentration were detected for miRNA-127, miRNA-133a, miRNA-181a, and miRNA-505 in this larger cohort. CONCLUSION: OSAS results in the nocturnal release of miRNAs into the bloodstream. Our collected data may indicate a hypoxia-induced release of miRNAs into the bloodstream of OSAS-patients. In vitro experiments are needed to confirm the secretion of these miRNAs under hypoxia and evaluate the effect on the cardio vasculature.

MicroRNA-mediated vascular intercellular communication is altered in chronic kidney disease.

AIMS: Chronic kidney disease (CKD) is an independent risk factor for the development of coronary artery disease (CAD). For both, CKD and CAD, the intercellular transfer of microRNAs (miRs) through extracellular vesicles (EVs) is an important factor of disease development. Whether the combination of CAD and CKD affects endothelial function through cellular crosstalk of EV-incorporated miRs is still unknown. METHODS AND RESULTS: Out of 172 screened CAD patients, 31 patients with CAD + CKD were identified and matched with 31 CAD patients without CKD. Additionally, 13 controls without CAD and CKD were included. Large EVs from CAD + CKD patients contained significantly lower levels of the vasculo-protective miR-130a-3p and miR-126-3p compared to CAD patients and controls. Flow cytometric analysis of plasma-derived EVs revealed significantly higher numbers of endothelial cell-derived EVs in CAD and CAD + CKD patients compared to controls. EVs from CAD + CKD patients impaired target human coronary artery endothelial cell (HCAEC) proliferation upon incubation in vitro. Consistent with the clinical data, treatment with the uraemia toxin indoxyl sulfate (IS)-reduced miR-130a-3p levels in HCAEC-derived EVs. EVs from IS-treated donor HCAECs-reduced proliferation and re-endothelialization in EV-recipient cells and induced an anti-angiogenic gene expression profile. In a mouse-experiment, intravenous treatment with EVs from IS-treated endothelial cells significantly impaired endothelial regeneration. On the molecular level, we found that IS leads to an up-regulation of the heterogenous nuclear ribonucleoprotein U (hnRNPU), which retains miR-130a-3p in the cell leading to reduced vesicular miR-130a-3p export and impaired EV-recipient cell proliferation. CONCLUSION: Our findings suggest that EV-miR-mediated vascular intercellular communication is altered in patients with CAD and CKD, promoting CKD-induced endothelial dysfunction.