Mitral transcatheter edge-to-edge repair vs. isolated mitral surgery for severe mitral regurgitation: a French nationwide study.

BACKGROUND AND AIMS: Mitral valve surgery and, more recently, mitral transcatheter edge-to-edge repair (TEER) are the two treatments of severe mitral regurgitation in eligible patients. Clinical comparison of both therapies remains limited by the number of patients analysed. The objective of this study was to analyse the outcomes of mitral TEER vs. isolated mitral valve surgery at a nationwide level in France. METHODS: Based on the French administrative hospital discharge database, the study collected information for all consecutive patients treated for mitral regurgitation with isolated TEER or isolated mitral valve surgery between 2012 and 2022. Propensity score matching was used for the analysis of outcomes. RESULTS: A total of 57 030 patients were found in the database. After matching on baseline characteristics, 2160 patients were analysed in each arm. At 3-year follow-up, TEER was associated with significantly lower incidence of cardiovascular death (hazard ratio 0.685, 95% confidence interval 0.563-0.832; P = .0001), pacemaker implantation, and stroke. Non-cardiovascular death (hazard ratio 1.562, 95% confidence interval 1.238-1.971; P = .0002), recurrent pulmonary oedema, and cardiac arrest were more frequent after TEER. No significant differences between the two groups were observed regarding all-cause death (hazard ratio 0.967, 95% confidence interval 0.835-1.118; P = .65), endocarditis, major bleeding, atrial fibrillation, and myocardial infarction. CONCLUSIONS: Our results suggest that TEER for severe mitral regurgitation was associated with lower cardiovascular mortality than mitral surgery at long-term follow-up. Pacemaker implantation and stroke were less frequently observed after TEER.

Antithrombotic Therapy Following Structural Heart Disease Interventions: Current Status and Future Directions.

Interventions in structural heart disease cover many catheter-based procedures for congenital and acquired conditions including valvular diseases, septal defects, arterial or venous obstructions, and fistulas. Among the available procedures, the most common are aortic valve implantation, mitral or tricuspid valve repair/implantation, left atrial appendage occlusion, and patent foramen ovale closure. Antithrombotic therapy for transcatheter structural heart disease interventions aims to prevent thromboembolic events and reduce the risk of short-term and long-term complications. The specific approach to antithrombotic therapy depends on the type of intervention and individual patient factors. In this review, we synopsize contemporary evidence on antithrombotic therapies for structural heart disease interventions and highlight the importance of a personalized approach. These recommendations may evolve over time as new evidence emerges and clinical guidelines are updated. Therefore, it's crucial for healthcare professionals to stay updated on the most recent guidelines and individualize therapy based on patient-specific factors and procedural considerations.

Remote proctoring during structural heart procedures: Toward a widespread diffusion of knowledge using mixed reality.

BACKGROUND: Despite its wide diffusion in surgical procedures, very few experiences are reported so far about the possible applications of remote proctoring (RP) in structural heart interventions. AIMS: Our aim was to demonstrate the feasibility, safety, and efficacy of RP during transcatheter edge-to-edge repair using a mixed reality-based head-mounted display (HMD). METHODS: Two users (a doctor and a proctor), wearing HMDs, were connected through a 5G network, allowing them to share audio and video signals. During the procedure, the proctor was located in a contiguous room, without any direct connection with the operator. The primary endpoint was noninferiority of HMD-mediated interaction if compared with direct in-person interaction. It was assessed using an operator-proctor interaction test based on six questions asked by the doctor to the proctor on six key procedural steps. RESULTS: Between September 2021 and April 2022, nine patients were enrolled in the study (15 clips delivered). The primary endpoint was reached in 9/15 clips implanted (60%). The first three failures were due to a chat software problem, and the others were linked with a 5G network malfunction. However, the HMD and its mixed reality tools were well tolerated by the operators, and no interference with the procedure was registered in any of the cases. CONCLUSIONS: In our experience, RP during structural heart interventions is feasible and efficacious. Wearing the HMD is comfortable and does not affect safety and effectiveness of interventional procedures. However, especially if considering a wide geographic use of this tool, a stable internet connection is imperative.

Minimum information for reporting on the TEER (trans-epithelial/endothelial electrical resistance) assay (MIRTA).

Standard information reporting helps to ensure that assay conditions and data are consistently reported and to facilitate inter-laboratory comparisons. Here, we present recommendations on minimum information for reporting on the TEER (trans-epithelial/endothelial electrical resistance) assay (MIRTA). The TEER assay is extensively used to evaluate the health of an epithelial/endothelial cell culture model and as an indicator of the potential toxicity of a test substance. This publication is the result of an international collaboration─called the RespTox (Respiratory Toxicity) Collaborative─through which twelve laboratories shared their protocols for assessing the barrier function of respiratory epithelial cells using the TEER assay following exposure to substances. The protocols from each laboratory were reviewed to identify general steps for performing the TEER assay, interlaboratory differences between steps, the rationale for differences, whether these differences impact results or cross-laboratory comparisons between TEER measurements. While the MIRTA recommendations are focused on respiratory epithelial cell systems, these recommendations can be adapted for other cell systems that form barriers. The use of these recommendations will support data transparency and reproducibility, reduce challenges in data interpretation, enable cross-laboratory comparisons, help assess study quality, and facilitate the incorporation of the TEER assay into national and international testing guidance.

Guideline-endorsed follow-up after percutaneous valve therapies-non-attendance of TAVI and MitraClip patients.

BACKGROUND: Percutaneous valve therapies (PVT) are performed on a large number of patients. With increasing procedural volume, the need for follow-up has also increased. Follow-up in the heart valve clinic is endorsed by recent guidelines but utilization is unknown, making resource allocation in the clinic difficult. Central follow-up in valve centers may not be feasible for all patients in the future. METHODS: In our center, follow-up for PVT patients is scheduled at 1 month and 12 months after the index procedure. Patients are reminded of their appointment by invitation letters or phone calls. We analyzed 150 consecutive patients who underwent transcutaneous aortic valve implantation (TAVI) and MitraClip implantation (n = 300) at our center. RESULTS: At 1 month, 72.7% of patients attended their follow-up, while at 12 months the rate dropped to 58%. Patients who underwent TAVI were older than the MitraClip patients (82.7 vs. 76.1 years) but had lower mean logEuroSCORE (22.6% vs. 25.9%). There was no significant difference in 1­year mortality between TAVI and MitraClip patients (20% vs. 17.3%). By contrast, the rate of missed follow-up visits was higher for TAVI compared to MitraClip patients (52% vs. 33.3%; p = 0.002). Female patients less frequently attended follow-up (p = 0.005), whereas age, EuroSCORE, NYHA class, ejection fraction, and health status (EQ-5DVAS) were not predictors of attendance in multivariable analysis. Although the result of the EQ-5D assessment was not associated with mortality or attendance, completing the questionnaire was associated with overall survival (p < 0.001). CONCLUSION: In our heart valve clinic, we observed a high percentage of missed follow-up appointments (42% at 12 months) despite a structured follow-up plan. Factors significantly associated with non-attendance in multivariable analysis were female gender and having a TAVI rather than MitraClip. Future follow-up concepts should take such findings into account, and decentralized approaches need to be explored.

Cerebral Embolic Protection: Is There a Benefit for Left Atrial and Mitral Valve Procedures?

PURPOSE OF REVIEW: This review aims to highlight the current evidence on the use of cerebral embolic protection devices (CEPD) in left atrial and transcatheter mitral valve procedures. It also aims to summarize the antithrombotic management of patients undergoing such procedures. RECENT FINDINGS: Ischemic stroke is one of the most devastating complications of structural heart procedures. The manifestation of periprocedural stroke can range from asymptomatic and detectable only through brain imaging to major stroke with neurological deficits. CEP devices were initially developed to mitigate the risk of stroke associated with transcatheter aortic valve replacement (TAVR). However, the efficacy of such devices during different cardiac interventions is yet to be fully demonstrated, especially in left atrial appendage closure (LAAO), and mitral valve interventions. Few studies demonstrated that the risk of periprocedural strokes after LAAO and mitral valve interventions is not negligible and is highest during the periprocedural period and then falls. The majority of patients undergoing those procedures have cerebral ischemic injuries detected on diffusion-weighted magnetic resonance imaging (DW-MRI). Moreover, a reasonable number of those patients had debris embolization on the filters of the CEPD. Pharmacological therapy with antithrombotic agents before, during, or after structural heart interventions is crucial and should be tailored to each patient's risk of bleeding and ischemia. Close monitoring that includes a full neurological assessment and frequent follow-up visits with cardiac echocardiography are important. The risk of periprocedural stroke in left atrial and transcatheter mitral valve procedures is not negligible. Pharmacological therapy with antithrombotic agents before, during, or after structural heart interventions is important to mitigate the risk of stroke, especially the long-term risk. More prospective studies are needed to assess the efficacy of CEPD in such procedures.

Neutrophil Extracellular Traps Affect Human Inner Ear Vascular Permeability.

The integrity of the blood-labyrinth barrier (BLB) is essential for inner ear homeostasis, regulating the ionic composition of endolymph and perilymph and preventing harmful substance entry. Endothelial hyperpermeability, central in inflammatory and immune responses, is managed through complex intercellular communication and molecular signaling pathways. Recent studies link BLB permeability dysregulation to auditory pathologies like acoustic trauma, autoimmune inner ear diseases, and presbycusis. Polymorphonuclear granulocytes (PMNs), or neutrophils, significantly modulate vascular permeability, impacting endothelial barrier properties. Neutrophil extracellular traps (NETs) are involved in diseases with autoimmune and autoinflammatory bases. The present study evaluated the impact of NETs on a BLB cellular model using a Transwell® setup. Our findings revealed a concentration-dependent impact of NETs on human inner ear-derived endothelial cells. In particular, endothelial permeability markers increased, as indicated by reduced transepithelial electrical resistance, enhanced dextran permeability, and downregulated junctional gene expression (ZO1, OCL, and CDH5). Changes in cytoskeletal architecture were also observed. These preliminary results pave the way for further research into the potential involvement of NETs in BLB impairment and implications for auditory disorders.

Bowel Inflammation and Nutrient Supplementation: Effects of a Fixed Combination of Probiotics, Vitamins, and Herbal Extracts in an In Vitro Model of Intestinal Epithelial Barrier Dysfunction.

The gut microbiota is a very important factor in the state of health of an individual, its alteration implies a situation of "dysbiosis," which can be connected to functional gastrointestinal disorders and pathological conditions, such as Inflammatory Bowel Disease (IBD), Irritable Bowel Syndrome (IBS), Ulcerative Colitis (UC) and Crohn's Disease (CD), and Colorectal Cancer (CRC). In this work, we studied the effect of a food supplement called ENTERO-AD containing a mix of probiotics (Lactobacillus acidophilus LA1, L. reuteri LR92, Bifidobacterium breve Bbr8), Matricaria Chamomilla, and B group vitamins (B1, B2, B6) on intestinal inflammation. The in vitro model used for the study is the Caco-2 cell, a culture derived from human intestinal adenocarcinoma; the inflammatory condition was achieved with treatment with Lipopolysaccharide (LPS) and the association between Tumor necrosis factor α/Interferon γ (TNF-α/IFN-γ) [1,2]. The effect of ENTERO-AD was evaluated by cell viability, measures of Transepithelial Electrical Resistance (TEER), paracellular permeability, and immunofluorescence. Results of the study have shown that ENTERO-AD has a favorable effect on Caco-2 cells in inflammatory conditions. It improves the integrity of Occludin and Zonula Occludens-1 (ZO-1) proteins, leading to an improvement in terms of TEER values and a reduction of paracellular permeability. This evidence underlines the protective effect of ENTERO-AD and its components in intestinal inflammation.

Fingolimod (FTY720), an FDA-approved sphingosine 1-phosphate (S1P) receptor agonist, restores endothelial hyperpermeability in cellular and animal models of dengue virus serotype 2 infection.

Extensive vascular leakage and shock is a major cause of dengue-associated mortality. At present, there are no specific treatments available. Sphingolipid pathway is a key player in the endothelial barrier integrity; and is mediated through the five sphingosine-1-phosphate receptors (S1PR1-S1PR5). Signaling through S1PR2 promotes barrier disruption; and in Dengue virus (DENV)-infection, there is overexpression of this receptor. Fingolimod (FTY720) is a specific agonist that targets the remaining barrier-protective S1P receptors, without targeting S1PR2. In the present study, we explored whether FTY720 treatment can alleviate DENV-induced endothelial hyperpermeability. In functional assays, in both in vitro systems and in AG129 animal models, FTY720 treatment was found effective. Upon treatment, there was complete restoration of the monolayer integrity in DENV serotype 2-infected human microvascular endothelial cells (HMEC-1). At the molecular level, the treatment reversed activation of the S1P pathway. It significantly reduced the phosphorylation of the key molecules such as PTEN, RhoA, and VE-Cadherin; and also, the expression levels of S1PR2. In DENV2-infected AG129 mice treated with FTY720, there was significant improvement in weight gain, in overall clinical symptoms, and in survival. Whereas 100% of the DENV2-infected, untreated animals died by day-10 post-infection, 70% of the FTY720-treated animals were alive; and at the end of the 15-day post-infection observation period, 30% of them were still surviving. There was a significant reduction in the Evan's-blue dye permeability in the organs of FTY720-treated, DENV-2 infected animals; and also improvement in the hemogram, with complete restoration of thrombocytopenia and hepatic function. Our results show that the FDA-approved molecule Fingolimod (FTY720) is a promising therapeutic intervention in severe dengue.

Phloretin suppresses intestinal inflammation and maintained epithelial tight junction integrity by modulating cytokines secretion in in vitro model of gut inflammation.

Ulcerative colitis is a type of inflammatory bowel disease which in long run can lead to colorectal cancer (CRC). Chronic inflammation can be a key factor for the occurrence of CRC thus mitigating an inflammation can be a preventive strategy for the occurrence of CRC. In this study we have explored the anti-inflammatory potential of phloretin, in in vitro gut inflammation model, developed by co-culture of Caco2 (intestinal epithelial) cells and RAW264.7 macrophages (immune cells). Phloretin is a dihydrochalcone present in apple, pear and strawberries. An anti-inflammatory effect of phloretin in reducing LPS induced inflammation and maintenance of transepithelial electric resistance (TEER) in Caco2 cells was examined. Paracellular permeability assay was performed using Lucifer yellow dye to evaluate the effect of phloretin in inhibiting gut leakiness caused by inflammatory mediators secreted by activated macrophages. Phloretin attenuated LPS induced nitric oxide levels, oxidative stress, depolarization of mitochondrial membrane potential in Caco2 cells as evidenced by reduction in reactive oxygen species (ROS), and enhancement of MMP, and decrease in inflammatory cytokines IL8, TNFα, IL1ß and IL6. It exhibited anti-inflammatory activity by inhibiting the expression of NFκB, iNOS and Cox2. Phloretin maintained the epithelial integrity by regulating the expression of tight junction proteins ZO1, occludin, Claudin1 and JAM. Phloretin reduced LPS induced levels of Cox2 along with the reduction in Src expression which further regulated an expression of tight junction protein occludin. Phloretin in combination to sodium pyruvate exhibited potential anti-inflammatory activity via targeting NFkB signaling. Our findings paved a way to position phloretin as nutraceutical in preventing the occurrence of colitis and culmination of disease into colitis associated colorectal cancer.

Papillary muscle rupture after transcatheter aortic valve implantation: A case report and literature review.

We present a case of posterior papillary muscle rupture associated with severe eccentric mitral regurgitation following transcatheter aortic valve implantation, that was successfully treated with transcatheter edge to edge mitral repair and review similar cases in literature.

Impact of concomitant tricuspid regurgitation on outcome after edge-to-edge mitral valve repair.

AIMS: To evaluate the impact of tricuspid regurgitation (TR) on echocardiographic and functional outcome after mitral valve transcatheter edge-to-edge-repair (M-TEER). METHODS AND RESULTS: A total of 740 patients underwent M-TEER at our center from 2010 to 2021. Patients were analyzed according to severity of concomitant TR at the time of M-TEER procedure: low-grade TR (grade ≤I [trace-mild], 279 patients [37.7%]), moderate TR (grade II, 170 patients [23.0%]) and high-grade TR (grade III-V [severe-torrential], 291 patients [39.3%]). Patients with moderate to high-grade TR had higher morbidity. Procedural success of M-TEER was achieved similarly in all groups (98.2% vs. 97.6% vs. 95.9%, p = 0.22). TR severity decreased rapidly and consistently after M-TEER to only 48.0% of high-grade TR patients after 3 months (p < 0.001) and to 46.8% after 12 months (p = 0.99). High-grade TR patients had significantly higher mortality (21.5% vs. 18.2% vs. 11.1%, p = 0.003) up to 12 months after M-TEER. However, high-grade TR did not independently predict mortality (HR 1.302, 95% CI 0.937-1.810; p = 0.116). Echocardiographic and functional outcome was similar in both secondary and primary MR patients. CONCLUSIONS: High-grade concomitant TR did not independently predict adverse outcome following M-TEER. A wait-and-observe approach for these patients is reasonable.

Postprocedural trans-mitral gradient in patients with degenerative mitral regurgitation undergoing mitral valve transcatheter edge-to-edge repair.

BACKGROUND: The relationship between high postprocedural mean gradient (ppMG) and clinical events following mitral valve transcatheter edge-to-edge repair (MV-TEER) in patients with degenerative mitral regurgitation (DMR) is still debated. AIM: The purpose of this study was to evaluate the effect of elevated ppMG after MV-TEER on clinical events in patients with DMR at 1-year follow-up. METHODS: The study included 371 patients with DMR treated with MV-TEER enrolled in the "Multi-center Italian Society of Interventional Cardiology (GISE) registry of trans-catheter treatment of mitral valve regurgitation" (GIOTTO) registry. Patients were stratified in tertiles according to ppMG. Primary endpoint was a composite of all-cause death and hospitalization due to heart failure at 1-year follow-up. RESULTS: Patients were stratified as follows: 187 with a ppMG ≤ 3 mmHg, 77 with a ppMG > 3/=4 mmHg, and 107 with a ppMG > 4 mmHg. Clinical follow-up was available in all subjects. At multivariate analysis, neither a ppMG > 4 mmHg nor a ppMG ≥ 5 mmHg were independently associated with the outcome. Notably, the risk of elevated residual MR (rMR > 2+) was significantly higher in patients belonging to the highest tertile of ppMG (p = 0.009). The association of ppMG > 4 mmHg and rMR ≥ 2+ was strongly and independently associated with adverse events (hazard ratio: 1.98; 95% confidence interval: [1.10-3.58]). CONCLUSIONS: In a real-world cohort of patients suffering DMR and treated with MV-TEER, isolated ppMG was not associated with the outcome at 1-year follow-up. A high proportion of patients showed both elevated ppMG and rMR and their combination appeared to be a strong predictor of adverse events.

Basic Fibroblast Growth Factor Opens and Closes the Endothelial Blood-Brain Barrier in a Concentration-Dependent Manner.

Multiple paracrine factors are implicated in the regulation of barrier properties of human brain endothelial cells (BECs) in different physiologic and pathologic settings. We have recently demonstrated that autocrine secretion of basic fibroblast growth factor (bFGF) by BECs is necessary for the establishment of endothelial barrier (as demonstrated by high trans-endothelial electric resistance, TEER), whereas exogenous bFGF inhibits TEER in a concentration-dependent manner. In the present study we analysed the contribution of MAPK/ERK and STAT3 signalling pathways to the inhibitory effects of exogenous bFGF. Treatment with bFGF (8 ng/ml) for 3 days increased phosphorylation of ERK1/2 and STAT3. Treatment with FGF receptor 1 (FGFR1) inhibitor PD173074 (15 µM) suppressed both basal and bFGF-induced activation of ERK1/2 and STAT3. Suppression of STAT signalling with Janus kinase inhibitor JAKi (15 nM) alone or in the presence of bFGF did not change TEER in BEC monolayers. Exposure to JAKi affected neither proliferation, nor expression and distribution of tight junction (TJ) proteins claudin-5, occludin and zonula occludens-1 (ZO-1). In contrast, treatment with MEK 1/2 inhibitor U0126 (10 µM) partially neutralised inhibitory effect of bFGF thus increasing TEER, whereas U0126 alone did not affect resistance of endothelial barrier. Our findings demonstrate that MAPK/ERK signalling pathway does not affect autocrine bFGF signalling-dependent BECs barrier function but is largely responsible for the disruptive effects of the exogenous bFGF. We speculate that bFGF may (depending on concentration and possibly origin) dynamically regulate permeability of the endothelial blood-brain barrier.

Three-year outcomes for transcatheter repair in patients with mitral regurgitation from the CLASP study.

BACKGROUND: Mitral valve transcatheter edge-to-edge repair (M-TEER) is an effective option for treatment of mitral regurgitation (MR). We previously reported favorable 2-year outcomes for the PASCAL transcatheter valve repair system. OBJECTIVES: We report 3-year outcomes from the multinational, prospective, single-arm CLASP study with analysis by functional MR (FMR) and degenerative MR (DMR). METHODS: Patients with core-lab determined MR ≥ 3+ were deemed candidates for M-TEER by the local heart team. Major adverse events were assessed by an independent clinical events committee to 1 year and by sites thereafter. Echocardiographic outcomes were evaluated by the core laboratory to 3 years. RESULTS: The study enrolled 124 patients, 69% FMR; 31% DMR (60% NYHA class III-IVa, 100% MR ≥ 3+). The 3-year Kaplan-Meier estimate for survival was 75% (66% FMR; 92% DMR) and freedom from heart failure hospitalization (HFH) was 73% (64% FMR; 91% DMR), with 85% reduction in annualized HFH rate (81% FMR; 96% DMR) (p < 0.001). MR ≤ 2+ was achieved and maintained in 93% of patients (93% FMR; 94% DMR) and MR ≤ 1+ in 70% of patients (71% FMR; 67% DMR) (p < 0.001). The mean left ventricular end-diastolic volume (181 mL at baseline) decreased progressively by 28 mL [p < 0.001]. NYHA class I/II was achieved in 89% of patients (p < 0.001). CONCLUSIONS: The 3-year results from the CLASP study demonstrated favorable and durable outcomes with the PASCAL transcatheter valve repair system in patients with clinically significant MR. These results add to the growing body of evidence establishing the PASCAL system as a valuable therapy for patients with significant symptomatic MR.

Beneficial effects of GABA-producing potential probiotic Limosilactobacillus fermentum L18 of human origin on intestinal permeability and human gut microbiota.

BACKGROUND: Gamma-aminobutyric acid (GABA) is a non-protein amino acid with neuroinhibitory, antidiabetic, and antihypertensive properties and is used as a drug for treating anxiety and depression. Some strains of lactobacilli are known to produce GABA and strengthen the gut barrier function which play an important role in ameliorating the effects caused by the pathogen on the gut barrier. The probiotic bacteria are also known to modulate the human fecal microbiota, however, the role of GABA-producing strains on the gut epithelium permeability and gut microbiota is not known. RESULTS: In this study, we report the production of high levels of GABA by potential probiotic bacterium Limosilactobacillus fermentum L18 for the first time. The kinetics of the production of GABA by L18 showed that the maximum production of GABA in the culture supernatant (CS) occurred at 24 h, whereas in fermented milk it took 48 h of fermentation. The effect of L18 on the restoration of lipopolysaccharide (LPS)-disrupted intestinal cell membrane permeability in Caco-2 monolayers showed that it significantly restored the transepithelial electrical resistance (TEER) values, by significantly increasing the levels of junction proteins, occludin and E-cadherin in L18 and LPS-treated Caco-2 cells as compared to only LPS-treated cells. The effect of GABA-secreting L18 on the metataxonome of human stool samples from healthy individuals was investigated by a batch fermentor that mimics the conditions of the human colon. Although, no differences were observed in the α and ß diversities of the L18-treated and untreated samples at 24 h, the relative abundances of bacterial families Lactobacillaceae and Bifidobacteriaceae increased in the L18-treated group, but both decreased in the untreated groups. On the other hand, the relative abundance of Enterobacteriaceae decreased in the L18 samples but it increased in the untreated samples. CONCLUSION: These results indicate that Li. fermentum L18 is a promising GABA-secreting strain that strengthens the gut epithelial barrier by increasing junction protein concentrations and positively modulating the gut microbiota. It has the potential to be used as a psychobiotic or for the production of functional foods for the management of anxiety-related illnesses.

BBB-on-a-chip with integrated micro-TEER for permeability evaluation of multi-functionalized gold nanorods against Alzheimer's disease.

BACKGROUND: The lack of predictive models that mimic the blood-brain barrier (BBB) hinders the development of effective drugs for neurodegenerative diseases. Animal models behave differently from humans, are expensive and have ethical constraints. Organ-on-a-chip (OoC) platforms offer several advantages to resembling physiological and pathological conditions in a versatile, reproducible, and animal-free manner. In addition, OoC give us the possibility to incorporate sensors to determine cell culture features such as trans-endothelial electrical resistance (TEER). Here, we developed a BBB-on-a-chip (BBB-oC) platform with a TEER measurement system in close distance to the barrier used for the first time for the evaluation of the permeability performance of targeted gold nanorods for theranostics of Alzheimer's disease. GNR-PEG-Ang2/D1 is a therapeutic nanosystem previously developed by us consisting of gold nanorods (GNR) functionalized with polyethylene glycol (PEG), angiopep-2 peptide (Ang2) to overcome the BBB and the D1 peptide as beta amyloid fibrillation inhibitor, finally obtaining GNR-PEG-Ang2/D1 which showed to be useful for disaggregation of the amyloid in in vitro and in vivo models. In this work, we evaluated its cytotoxicity, permeability, and some indications of its impact on the brain endothelium by employing an animal-free device based on neurovascular human cells. RESULTS: In this work, we fabricated a BBB-oC with human astrocytes, pericytes and endothelial cells and a TEER measuring system (TEER-BBB-oC) integrated at a micrometric distance of the endothelial barrier. The characterization displayed a neurovascular network and the expression of tight junctions in the endothelium. We produced GNR-PEG-Ang2/D1 and determined its non-cytotoxic range (0.05-0.4 nM) for plated cells included in the BBB-oC and confirmed its harmless effect at the highest concentration (0.4 nM) in the microfluidic device. The permeability assays revealed that GNR-PEG-Ang2/D1 cross the BBB and this entry is facilitated by Ang2 peptide. Parallel to the permeability analysis of GNR-PEG-Ang2/D1, an interesting behavior of the TJs expression was observed after its administration probably related to the ligands on the nanoparticle surface. CONCLUSIONS: BBB-oC with a novel TEER integrated setup which allow a correct read-out and cell imaging monitoring was proven as a functional and throughput platform to evaluate the brain permeability performance of nanotherapeutics in a physiological environment with human cells, putting forward a viable alternative to animal experimentation.

[Interventional treatment of heart failure : Stents and valves]. / Interventionelle Therapie der Herzinsuffizienz : Stents und Klappen.

The pharmacotherapy of heart failure has evolved in recent years and with the aid of new classes of drugs symptomatic and prognostic improvements can be achieved in patients with heart failure. Heart failure is particularly frequently associated with coronary artery disease or higher grade, often functional valve defects. In the context of the underlying disease, the operative risk is often increased, so that interventional treatment is preferred over surgical treatment options in interdisciplinary heart teams. Promising approaches with very different challenges are emerging for interventional myocardial revascularization and percutaneous correction of high-grade aortic valve stenosis or functional mitral or tricuspid valve regurgitation. It has consistently been shown that an elaborate diagnostic work-up and differentiated patient selection are decisive to achieve a prognostic or symptomatic benefit in these patients using interventional treatment. While awaiting further study data on this topic, the integration of a multidisciplinary heart team is essential to ensure a complementary and balanced therapeutic approach for patient-centered care in this complex patient population.

Update on Transcatheter Treatment of Mitral and Tricuspid Valve Regurgitation.

PURPOSE OF REVIEW: Mitral and tricuspid regurgitation represents a clinical challenge. They are associated with a poor prognosis, and many patients are not eligible for conventional surgery. Transcatheter therapies have been the focus of numerous studies and devices over the past decade. Here, we provide a summary of current options for transcatheter treatment of these 2 entities. RECENT FINDINGS: Recent studies have demonstrated the benefits of edge-to-edge repair for increasing numbers of patients. Encouraging early results with transcatheter valve replacement are also becoming available. To date, transcatheter edge-to-edge repair is currently the first-line transcatheter treatment for both mitral and tricuspid regurgitation for many patients who are not candidates for surgery. A number of transcatheter replacement devices are under development and clinical investigation but, for the most part, their current use is limited to compassionate cases or clinical trials.

Establishing Co-Culture Blood-Brain Barrier Models for Different Neurodegeneration Conditions to Understand Its Effect on BBB Integrity.

The blood-brain barrier (BBB) is a functional interface that provides selective permeability, protection from toxic substances, transport of nutrients, and clearance of brain metabolites. Additionally, BBB disruption has been shown to play a role in many neurodegenerative conditions and diseases. Therefore, the aim of this study was to establish a functional, convenient, and efficient in vitro co-cultured BBB model that can be used for several physiological conditions related to BBB disruption. Mouse brain-derived endothelial (bEnd.3) and astrocyte (C8-D1A) cells were co-cultured on transwell membranes to establish an intact and functional in vitro model. The co-cultured model and its effects on different neurological diseases and stress conditions, including Alzheimer's disease (AD), neuroinflammation, and obesity, have been examined by transendothelial electrical resistance (TEER), fluorescein isothiocyanate (FITC) dextran, and tight junction protein analyses. Scanning electron microscope images showed evidence of astrocyte end-feet processes passing through the membrane of the transwell. Moreover, the co-cultured model showed effective barrier properties in the TEER, FITC, and solvent persistence and leakage tests when compared to the mono-cultured model. Additionally, the immunoblot results showed that the expression of tight junction proteins such as zonula occludens-1 (ZO-1), claudin-5, and occludin-1 was enhanced in the co-culture. Lastly, under disease conditions, the BBB structural and functional integrity was decreased. The present study demonstrated that the co-cultured in vitro model mimicked the BBB's structural and functional integrity and, under disease conditions, the co-cultured model showed similar BBB damages. Therefore, the present in vitro BBB model can be used as a convenient and efficient experimental tool to investigate a wide range of BBB-related pathological and physiological studies.