Volume of contrast to creatinine clearance ratio predicts early mortality and AKI after TAVI.

The volume of contrast to creatinine clearance ratio (CV/CrCl) is a useful indicator of the risk of acute kidney injury (AKI) in patients undergoing percutaneous interventional procedures. Association between CV/CrCl and adverse outcome after transcatheter aortic valve implantation (TAVI) was suggested but it is not well established. A large retrospective multicenter cohort of 1381 patients treated with TAVI was analyzed to assess the association between CV/CrCl and the risk of AKI and mortality at 90 days and 1 year after TAVI. Patients receiving renal replacement therapy at the time of TAVI were excluded. CV/CrCl ≥ 2.2 was associated with the risk of AKI and 90 days mortality after TAVI after adjustment for age, sex, diabetes, baseline left ventricular function, baseline chronic kidney disease (CKD), previous myocardial infarction and peripheral vascular disease (hazard ratio [HR]: 1.16, 95% confidence interval [CI]: 1.09-1.22, p < 0.0001). Importantly, CV/CrCl was associated with the adverse outcome independently from the presence of baseline CKD (p for interaction = 0.22). CV/CrCl was independently associated with the individual components of the composite primary outcome including AKI (odds ratio: 1.18, 95% CI: 1.08-1.28, p < 0.0001) and 90 days mortality (HR: 1.90, 95% CI: 1.01-3.60, p = 0.047) after TAVI. AKI (HR: 1.94, 95% CI: 1.21-3.11, p = 0.006) but not CV/CrCl was associated with the risk of 1-year mortality after TAVI. CV/CrCl is associated with excess renal damage and early mortality after TAVI. Procedural strategies to minimize the CV/CrCl during TAVI may improve early clinical outcomes in patients undergoing TAVI.

Modeling In Vitro Osteoarthritis Phenotypes in a Vascularized Bone Model Based on a Bone-Marrow Derived Mesenchymal Cell Line and Endothelial Cells.

The subchondral bone and its associated vasculature play an important role in the onset of osteoarthritis (OA). Integration of different aspects of the OA environment into multi-cellular and complex human, in vitro models is therefore needed to properly represent the pathology. In this study, we exploited a mesenchymal stromal cell line/endothelial cell co-culture to produce an in vitro human model of vascularized osteogenic tissue. A cocktail of inflammatory cytokines, or conditioned medium from mechanically-induced OA engineered microcartilage, was administered to this vascularized bone model to mimic the inflamed OA environment, hypothesizing that these treatments could induce the onset of specific pathological traits. Exposure to the inflammatory factors led to increased network formation by endothelial cells, reminiscent of the abnormal angiogenesis found in OA subchondral bone, demineralization of the constructs, and increased collagen production, signs of OA related bone sclerosis. Furthermore, inflammation led to augmented expression of osteogenic (alkaline phosphatase (ALP) and osteocalcin (OCN)) and angiogenic (vascular endothelial growth factor (VEGF)) genes. The treatment, with a conditioned medium from the mechanically-induced OA engineered microcartilage, also caused increased demineralization and expression of ALP, OCN, ADAMTS5, and VEGF; however, changes in network formation by endothelial cells were not observed in this second case, suggesting a possible different mechanism of action in inducing OA-like phenotypes. We propose that this vascularized bone model could represent a first step for the in vitro study of bone changes under OA mimicking conditions and possibly serve as a tool in testing anti-OA drugs.

Engineered human osteoarthritic cartilage organoids.

The availability of human cell-based models capturing molecular processes of cartilage degeneration can facilitate development of disease-modifying therapies for osteoarthritis [1], a currently unmet clinical need. Here, by imposing specific inflammatory challenges upon mesenchymal stromal cells at a defined stage of chondrogenesis, we engineered a human organotypic model which recapitulates main OA pathological traits such as chondrocyte hypertrophy, cartilage matrix mineralization, enhanced catabolism and mechanical stiffening. To exemplify the utility of the model, we exposed the engineered OA cartilage organoids to factors known to attenuate pathological features, including IL-1Ra, and carried out mass spectrometry-based proteomics. We identified that IL-1Ra strongly reduced production of the transcription factor CCAAT/enhancer-binding protein beta [2] and demonstrated that inhibition of the C/EBPß-activating kinases could revert the degradative processes. Human OA cartilage organoids thus represent a relevant tool towards the discovery of new molecular drivers of cartilage degeneration and the assessment of therapeutics targeting associated pathways.

Coronary microvascular dysfunction in patients undergoing transcatheter aortic valve implantation.

OBJECTIVES: This study aimed to evaluate the prognostic value of coronary microvascular dysfunction (CMD) at long term after transcatheter aortic valve implantation (TAVI) and to explore its relationship with extravalvular cardiac damage (EVCD). Moreover, we sought to test the correlation between angiography-derived index of microcirculatory resistance (IMRangio) and invasive IMR in patients with aortic stenosis (AS). METHODS: This was a retrospective analysis of the Verona Valvular Heart Disease Registry (Italy) including 250 patients (83 (80-86) years, 53% female) with severe AS who underwent TAVI between 2019 and 2021. IMRangio was calculated offline using a computational flow model applied to coronary angiography obtained during the TAVI workup. CMD was defined as IMRangio ≥30 units.The primary endpoint was the composite of cardiovascular death and rehospitalisation for heart failure (HF). Advanced EVCD was defined as pulmonary circulation impairment, severe tricuspid regurgitation or right ventricular dysfunction.The correlation between IMR and IMRangio was prospectively assessed in 31 patients undergoing TAVI. RESULTS: The primary endpoint occurred in 28 (11.2%) patients at a median follow-up of 22 (IQR 12-30) months. Patients with CMD met the primary endpoint more frequently than those without CMD (22.9% vs 2.8%, p<0.0001). Patients with CMD were more frequently characterised by advanced EVCD (33 (31.4%) vs 27 (18.6%), p=0.024). CMD was an independent predictor of adverse outcomes (adjusted HR 6.672 (2.251 to 19.778), p=0.001) and provided incremental prognostic value compared with conventional clinical and imaging variables. IMRangio demonstrated fair correlation with IMR. CONCLUSIONS: CMD is an independent predictor of cardiovascular mortality and HF after TAVI.

Cholangiocarcinoma-on-a-chip: A human 3D platform for personalised medicine.

Background & Aims: Cholangiocarcinoma (CCA) is a primary liver tumour characterised by a poor prognosis and limited therapeutic options. Available 3D human CCA models fail to faithfully recapitulate the tumour niche. We aimed to develop an innovative patient-specific CCA-on-chip platform. Methods: A CCA tumour microenvironment was recapitulated on a microfluidic three-channel chip using primary CCA cells, cancer-associated fibroblasts (CAFs), endothelial cells, and T cells isolated from CCA specimens (n = 6). CAF and CCA cells were co-cultured in the central channel, flanked by endothelial cells in one lateral channel, recreating a tubular structure. An extensive characterisation of this platform was carried out to investigate its diffusion ability, hydrogel properties, and changes in matrix composition. Cell phenotype and functional properties were assessed. Results: Primary cells seeded on the microfluidic device were shown to reproduce the architectural structure and maintain the original phenotype and functional properties. The tumour niche underwent a deep remodelling in the 3D device, with an increase in hydrogel stiffness and extracellular matrix deposition, mimicking in vivo CCA characteristics. T cells were incorporated into the device to assess its reliability for immune cell interaction studies. Higher T cell migration was observed using cells from patients with highly infiltrated tumours. Finally, the drug trial showed the ability of the device to recapitulate different drug responses based on patient characteristics. Conclusions: We presented a 3D CCA platform that integrates the major non-immune components of the tumour microenvironment and the T cell infiltrate, reflecting the CCA niche. This CCA-on-chip represents a reliable patient-specific 3D platform that will be of help to further elucidate the biological mechanisms involved in CCA and provide an efficient tool for personalised drug testing. Impact and implications: An innovative patient-specific cholangiocarcinoma (CCA)-on-chip platform was successfully developed, integrating the major components of the tumour microenvironment (tumour cells, cancer-associated fibroblasts, endothelial cells, and immune infiltrate) and faithfully mimicking the CCA niche. This CCA-on-chip represents a powerful tool for unravelling disease-associated cellular mechanisms in CCA and provides an efficient tool for personalised drug testing.

Characterisation of coronary microvascular dysfunction in patients with severe aortic stenosis undergoing TAVI.

BACKGROUND: Microvascular resistance reserve (MRR) is a validated measure of coronary microvascular function independent of epicardial resistances. AIMS: We sought to assess whether MRR is associated with adverse cardiac remodelling, a low-flow phenotype and extravalvular cardiac damage (EVCD) in patients with severe aortic stenosis (AS) undergoing transcatheter aortic valve implantation (TAVI). METHODS: Invasive thermodilution-based assessment of the coronary microvascular function of the left anterior descending artery was performed in a prospective, multicentre cohort of patients undergoing TAVI. Coronary microvascular dysfunction (CMD) was defined as the lowest MRR tertile of the study cohort. Haemodynamic measurements were performed at baseline and then repeated immediately after TAVI. EVCD and markers of a low-flow phenotype were assessed with echocardiography. RESULTS: A total of 134 patients were included in this study. Patients with low MRR were more frequently females, had a lower estimated glomerular filtration rate and a higher rate of atrial fibrillation. MRR was significantly lower in patients with advanced EVCD (median 1.80 [1.26-3.30] vs 2.50 [1.87-3.41]; p=0.038) and in low-flow, low-gradient AS (LF LG-AS) (median 1.85 [1.20-3.04] vs 2.50 [1.87-3.40]; p=0.008). Overall, coronary microvascular function tended to improve after TAVI and, in particular, MRR increased significantly after TAVI in the subgroup with low MRR at baseline. However, MRR was significantly impaired in 38 (28.4%) patients immediately after TAVI. Advanced EVCD (adjusted odds ratio 3.08 [1.22-7.76]; p=0.017) and a low-flow phenotype (adjusted odds ratio 3.36 [1.08-10.47]; p=0.036) were significant predictors of CMD. CONCLUSIONS: In this observational, hypothesis-generating study, CMD was associated with extravalvular cardiac damage and a low-flow phenotype in patients with severe AS undergoing TAVI.

One-year clinical outcomes of transcatheter aortic valve implantation with the latest iteration of self-expanding or balloonexpandable devices: insights from the OPERA-TAVI registry.

BACKGROUND: Midterm comparative analyses of the latest iterations of the most used Evolut and SAPIEN platforms for transcatheter aortic valve implantation (TAVI) are lacking. AIMS: We aimed to compare 1-year clinical outcomes of TAVI patients receiving Evolut PRO/PRO+ (PRO) or SAPIEN 3 Ultra (ULTRA) devices in current real-world practice. METHODS: Among patients enrolled in the OPERA-TAVI registry, patients with complete 1-year follow-up were considered for the purpose of this analysis. One-to-one propensity score matching was used to compare TAVI patients receiving PRO or ULTRA devices. The primary endpoint was a composite of 1-year all-cause death, disabling stroke and rehospitalisation for heart failure. Five prespecified subgroups of patients were considered according to leaflet and left ventricular outflow tract calcifications, annulus dimensions and angulation, and leaflet morphology. RESULTS: Among a total of 1,897 patients, 587 matched pairs of patients with similar clinical and anatomical characteristics were compared. The primary composite endpoint did not differ between patients receiving PRO or ULTRA devices (Kaplan-Meier [KM] estimates 14.0% vs 11.9%; log-rank p=0.27). Patients receiving PRO devices had higher rates of 1-year disabling stroke (KM estimates 2.6% vs 0.4%; log-rank p=0.001), predominantly occurring within 30 days after TAVI (1.4% vs 0.0%; p=0.004). Outcomes were consistent across all the prespecified subsets of anatomical scenarios (all pinteraction>0.10). CONCLUSIONS: One-year clinical outcomes of patients undergoing transfemoral TAVI and receiving PRO or ULTRA devices in the current clinical practice were similar, but PRO patients had higher rates of disabling stroke. Outcomes did not differ across the different anatomical subsets of the aortic root.

Evolut PRO and SAPIEN ULTRA Performance in Small Aortic Annuli: The OPERA-TAVI Registry.

BACKGROUND: The performance of latest iteration transcatheter aortic valve replacement platforms in patients with small aortic anatomy remains underexplored. OBJECTIVES: The aim of this study was to evaluate effectiveness and performance between the self-expanding (SE) Evolut PRO and PRO+ and the balloon-expandable (BE) SAPIEN ULTRA in patients with small aortic annuli. METHODS: Data from the OPERA-TAVI (Comparative Analysis of Evolut PRO vs. SAPIEN 3 ULTRA Valves for Transfemoral Transcatheter Aortic Valve Implantation) registry were used, with 1:1 propensity score matching. Primary endpoints included 1-year effectiveness composite (all-cause mortality, disabling stroke, or heart failure hospitalization) and 30-day device-related (hemodynamic structural valve dysfunction and nonstructural valve dysfunction) outcomes. RESULTS: Among 3,516 patients, 251 matched pairs with aortic annular area <430 mm2 were assessed. The 1-year primary effectiveness outcome did not differ significantly between cohorts (SE 10.8% vs BE 11.2%; P = 0.91). The 30-day device-oriented composite outcome was more favorable in the Evolut PRO group (SE 4.8% vs BE 10.4%; P = 0.027). Notably, SE valve recipients showed higher rates of disabling stroke (SE 4.0% vs BE 0.0%; P < 0.01) and paravalvular leaks (mild or greater: SE 48.5% vs BE 18.6% [P < 0.001]; moderate: SE 4.5% vs BE 1.2% [P = 0.070]). The BE group had higher rates of prosthesis-patient mismatch (moderate or greater: SE 16.0% vs BE 47.1% [P < 0.001]; severe: SE 1.3% vs BE 5.7% [P = 0.197]) and more patients with residual mean gradients >20 mm Hg (SE 1.0% vs BE 13.5%; P < 0.001). CONCLUSIONS: In patients with small aortic annuli, transcatheter aortic valve replacement with latest iteration devices is safe. SE platforms are associated with more favorable device performance in terms of hemodynamic structural and nonstructural dysfunction. Randomized data are needed to validate these findings and guide informed device selection.

Sex-Related Outcomes of Transcatheter Aortic Valve Implantation With Self-Expanding or Balloon-Expandable Valves: Insights from the OPERA-TAVI Registry.

Evidence regarding gender-related differences in response to transcatheter aortic valve implantation according to the valve type is lacking. This study aimed to evaluate the impact of gender on the treatment effect of Evolut PRO/PRO+ (PRO) or SAPIEN 3 Ultra (ULTRA) devices on clinical outcomes. The Comparative Analysis of Evolut PRO vs SAPIEN 3 Ultra Valves for Transfemoral Transcatheter Aortic Valve Implantation (OPERA-TAVI) is a multicenter, multinational registry including patients who underwent the latest-iteration PRO or ULTRA implantation. Overall, 1,174 of 1,897 patients were matched based on valve type and compared according to gender, whereas 470 men and 630 women were matched and compared according to valve type. The 30-day and 1-year outcomes were evaluated. In the PRO and ULTRA groups, men had a higher co-morbidity burden, whereas women had smaller aortic root. The 30-day (device success [DS], early safety outcome, permanent pacemaker implantation, patient-prosthesis mismatch, paravalvular regurgitation, bleedings, vascular complications, and all-cause death) and 1-year outcomes (all-cause death, stroke, and heart failure hospitalization) did not differ according to gender in both valve groups. However, the male gender decreased the likelihood of 30-day DS with ULTRA versus PRO (p for interaction = 0.047). A higher risk of 30-day permanent pacemaker implantation and 1-year stroke and a lower risk of patient-prosthesis mismatch was observed in PRO versus ULTRA, regardless of gender. In conclusion, gender did not modify the treatment effect of PRO versus ULTRA on clinical outcomes, except for 30-day DS, which was decreased in men (vs women) who received ULTRA (vs PRO).

Proof of concept study on coronary microvascular function in low flow low gradient aortic stenosis.

OBJECTIVES: We hypothesised that low flow low gradient aortic stenosis (LFLGAS) is associated with more severe coronary microvascular dysfunction (CMD) compared with normal-flow high-gradient aortic stenosis (NFHGAS) and that CMD is related to reduced cardiac performance. METHODS: Invasive CMD assessment was performed in 41 consecutive patients with isolated severe aortic stenosis with unobstructed coronary arteries undergoing transcatheter aortic valve implantation (TAVI). The index of microcirculatory resistance (IMR), resistive reserve ratio (RRR) and coronary flow reserve (CFR) were measured in the left anterior descending artery before and after TAVI. Speckle tracking echocardiography was performed to assess cardiac function at baseline and repeated at 6 months. RESULTS: IMR was significantly higher in patients with LFLGAS compared with patients with NFHGAS (24.1 (14.6 to 39.1) vs 12.8 (8.6 to 19.2), p=0.002), while RRR was significantly lower (1.4 (1.1 to 2.1) vs 2.6 (1.5 to 3.3), p=0.020). No significant differences were observed in CFR between the two groups. High IMR was associated with low stroke volume index, low cardiac output and reduced peak atrial longitudinal strain (PALS). TAVI determined no significant variation in microvascular function (IMR: 16.0 (10.4 to 26.1) vs 16.6 (10.2 to 25.6), p=0.403) and in PALS (15.9 (9.9 to 26.5) vs 20.1 (12.3 to 26.7), p=0.222). Conversely, left ventricular (LV) global longitudinal strain increased after TAVI (-13.2 (8.4 to 16.6) vs -15.1 (9.4 to 17.8), p=0.047). In LFLGAS, LV systolic function recovered after TAVI in patients with preserved microvascular function but not in patients with CMD. CONCLUSIONS: CMD is more severe in patients with LFLGAS compared with NFHGAS and is associated with low-flow state, left atrial dysfunction and reduced cardiac performance.

Angiography-Derived and Sensor-Wire Methods to Assess Coronary Microvascular Dysfunction in Patients With Acute Myocardial Infarction.

ST-segment elevation myocardial infarction (STEMI) treatment with primary percutaneous coronary intervention has dramatically impacted prognosis. However, despite satisfactory angiographic result, occurrence or persistence of coronary microvascular dysfunction after revascularization still affects long-term outcomes. The diagnostic and therapeutic value of understanding the status of coronary microcirculation is gaining attention in the cardiology community. However, current methods to assess microvascular function (namely, cardiac magnetic resonance and invasive wire-based coronary physiology) remain, at least in part, limited by technical and logistic aspects. On the other hand, angiography-based indices of microcirculatory resistance are emerging as valid and user-friendly tools with potential impact on prognostic stratification of patients with STEMI. This review provides an overview about conventional and novel methods to assess coronary microvascular dysfunction in patients with STEMI. The authors also provide a proposed procedural algorithm to facilitate optimal use of wire-based and angiography-based indices in the acute setting of STEMI.

Comparison of different percutaneous revascularisation timing strategies in patients undergoing transcatheter aortic valve implantation.

BACKGROUND: The optimal timing to perform percutaneous coronary interventions (PCI) in transcatheter aortic valve implantation (TAVI) patients remains unknown. AIMS: We sought to compare different PCI timing strategies in TAVI patients. METHODS: The REVASC-TAVI registry is an international registry including patients undergoing TAVI with significant, stable coronary artery disease (CAD) at preprocedural workup. In this analysis, patients scheduled to undergo PCI before, after or concomitantly with TAVI were included. The main endpoints were all-cause death and a composite of all-cause death, stroke, myocardial infarction (MI) or rehospitalisation for congestive heart failure (CHF) at 2 years. Outcomes were adjusted using the inverse probability treatment weighting (IPTW) method. RESULTS: A total of 1,603 patients were included. PCI was performed before, after or concomitantly with TAVI in 65.6% (n=1,052), 9.8% (n=157) or 24.6% (n=394), respectively. At 2 years, all-cause death was significantly lower in patients undergoing PCI after TAVI as compared with PCI before or concomitantly with TAVI (6.8% vs 20.1% vs 20.6%; p<0.001). Likewise, the composite endpoint was significantly lower in patients undergoing PCI after TAVI as compared with PCI before or concomitantly with TAVI (17.4% vs 30.4% vs 30.0%; p=0.003). Results were confirmed at landmark analyses considering events from 0 to 30 days and from 31 to 720 days. CONCLUSIONS: In patients with severe aortic stenosis and stable coronary artery disease scheduled for TAVI, performance of PCI after TAVI seems to be associated with improved 2-year clinical outcomes compared with other revascularisation timing strategies. These results need to be confirmed in randomised clinical trials.

Mechanical Induction of Osteoarthritis Traits in a Cartilage-on-a-Chip Model.

The present lack of effective therapies for osteoarthritis, the most diffused musculoskeletal disease, correlates with the absence of representative in vitro disease models. Microfabrication techniques and soft lithography allow the development of organs and tissues on chip with increased mimicry of human pathophysiology. Exploitation of polydimethylsiloxane elasticity, furthermore, permits to incorporate finely controlled mechanical actuators which are of the utmost importance in a faithful representation of the intrinsically active environment of musculoskeletal districts, to increase our comprehension of the disease onset and to successfully predict the response to pharmacological therapies. Here, we portray the fabrication and operational processes for the development of a cartilage-on-a-chip model. Additionally, we describe the methodologies to induce a phenotype reminiscent of osteoarthritis solely through hyperphysiological cyclic compression. The techniques to assess achievement of such features through immunofluorescence and gene expression are also detailed.

Organ-on-Chips for Studying Tissue Barriers: Standard Techniques and a Novel Method for Including Porous Membranes Within Microfluidic Devices.

A relevant number of organ-on-chips is aimed at modeling epithelial/endothelial interfaces between tissue compartments. These barriers help tissue function either by protecting (e.g., endothelial blood-brain barrier) or by orchestrating relevant molecular exchanges (e.g., lung alveolar interface) in human organs. Models of these biological systems are aimed at characterizing the transport of molecules, drugs or drug carriers through these specific barriers. Multilayer microdevices are particularly appealing to this goal and techniques for embedding porous membranes within organ-on-chips are therefore at the basis of the development and use of such systems. Here, we discuss and provide procedures for embedding porous membranes within multilayer organ-on-chips. We present standard techniques involving both custom-made polydimethylsiloxane (PDMS) membranes and commercially available plastic membranes. In addition, we present a novel method for fabricating and bonding PDMS porous membranes by using a cost-effective epoxy resin in place of microfabricated silicon wafers as master molds.

Chondrocyte Hypertrophy in Osteoarthritis: Mechanistic Studies and Models for the Identification of New Therapeutic Strategies.

Articular cartilage shows limited self-healing ability owing to its low cellularity and avascularity. Untreated cartilage defects display an increased propensity to degenerate, leading to osteoarthritis (OA). During OA progression, articular chondrocytes are subjected to significant alterations in gene expression and phenotype, including a shift towards a hypertrophic-like state (with the expression of collagen type X, matrix metalloproteinases-13, and alkaline phosphatase) analogous to what eventuates during endochondral ossification. Present OA management strategies focus, however, exclusively on cartilage inflammation and degradation. A better understanding of the hypertrophic chondrocyte phenotype in OA might give new insights into its pathogenesis, suggesting potential disease-modifying therapeutic approaches. Recent developments in the field of cellular/molecular biology and tissue engineering proceeded in the direction of contrasting the onset of this hypertrophic phenotype, but knowledge gaps in the cause-effect of these processes are still present. In this review we will highlight the possible advantages and drawbacks of using this approach as a therapeutic strategy while focusing on the experimental models necessary for a better understanding of the phenomenon. Specifically, we will discuss in brief the cellular signaling pathways associated with the onset of a hypertrophic phenotype in chondrocytes during the progression of OA and will analyze in depth the advantages and disadvantages of various models that have been used to mimic it. Afterwards, we will present the strategies developed and proposed to impede chondrocyte hypertrophy and cartilage matrix mineralization/calcification. Finally, we will examine the future perspectives of OA therapeutic strategies.

Optimal timing for percutaneous coronary intervention in patients undergoing transcatheter aortic valve implantation.

BACKGROUND: The best timing to perform percutaneous coronary interventions (PCI) in patients undergoing TAVI is unknown. Most PCI are performed before TAVI, because of concerns about potential ischemic complications during valve implantation. In this study we aimed to compare short-and long-term outcomes of patients undergoing PCI before or after TAVI. METHODS: Patients undergoing TAVI and PCI from 2010 to 2021 were analyzed. PCI was defined as high-risk when involving unprotected left main, proximal left anterior descending, proximal dominant right coronary artery or 3-vessel disease. The primary endpoint was the cumulative incidence of any TAVI procedural complication and in-hospital adverse events (VARC-3 criteria). RESULTS: Out of 1162 patients, 144 underwent PCI, 68% after TAVI, 78.4% of which were at high-risk. The primary endpoint occurred in 28.4% of patients in PCI pre-TAVI group vs 21.4% in PCI post-TAVI group (p = 0.403) and in 34.4% vs 17.3% of patients respectively among high-risk patients (p = 0.075). A higher rate of stroke was observed in the PCI pre-TAVI group regardless of the PCI complexity (6.5% vs 0.0%, p = 0.031; 9.3% vs 0.0% p = 0.025 in the high-risk group). At 24 months, MACCE-free survival was lower in patients who underwent PCI before TAVI (84.4% vs 97.9%, adjusted HR 10.16, 95% CI 1.19-86.57, p = 0.019; and 84.4% vs 97.3%, adjusted HR 7.34 95% CI 0.78-62.28 p = 0.082 in the high-risk group). CONCLUSIONS: PCI performed after TAVI does not expose patients to higher risks of peri-procedural hazards and provides a trend towards favourable clinical outcome at mid-to-long term.

Management of Myocardial Revascularization in Patients With Stable Coronary Artery Disease Undergoing Transcatheter Aortic Valve Implantation.

BACKGROUND: The best management of stable coronary artery disease (CAD) in patients undergoing transcatheter aortic valve implantation (TAVI) is still unclear due to the marked inconsistency of the available evidence. METHODS: The REVASC-TAVI registry (Management of Myocardial Revascularization in Patients Undergoing Transcatheter Aortic Valve Implantation With Coronary Artery Disease) collected data from 30 centers worldwide on patients undergoing TAVI who had significant, stable CAD at preprocedural work-up. For the purposes of this analysis, patients with either complete or incomplete myocardial revascularization were compared in a propensity score matched analysis, to take into account of baseline confounders. The primary and co-primary outcomes were all-cause death and the composite of all-cause death, stroke, myocardial infarction, and rehospitalization for heart failure, respectively, at 2 years. RESULTS: Among 2407 patients enrolled, 675 pairs of patients achieving complete or incomplete myocardial revascularization were matched. The primary (21.6% versus 18.2%, hazard ratio' 0.88 [95% CI, 0.66-1.18]; P=0.38) and co-primary composite (29.0% versus 27.1%, hazard ratio' 0.97 [95% CI, 0.76-1.24]; P=0.83) outcome did not differ between patients achieving complete or incomplete myocardial revascularization, respectively. These results were consistent across different prespecified subgroups of patients (< or >75 years of age, Society of Thoracic Surgeons score > or <4%, angina at baseline, diabetes, left ventricular ejection fraction > or <40%, New York Heart Association class I/II or III/IV, renal failure, proximal CAD, multivessel CAD, and left main/proximal anterior descending artery CAD; all P values for interaction >0.10). CONCLUSIONS: The present analysis of the REVASC-TAVI registry showed that, among TAVI patients with significant stable CAD found during the TAVI work-up, completeness of myocardial revascularization achieved either staged or concomitantly with TAVI was similar to a strategy of incomplete revascularization in reducing the risk of all cause death, as well as the risk of death, stroke, myocardial infarction, and rehospitalization for heart failure at 2 years, regardless of the clinical and anatomical situations.

A dynamic microscale mid-throughput fibrosis model to investigate the effects of different ratios of cardiomyocytes and fibroblasts.

Cardiac fibrosis is a maladaptive remodeling of the myocardium hallmarked by contraction impairment and excessive extracellular matrix deposition (ECM). The disease progression, nevertheless, remains poorly understood and present treatments are not capable of controlling the scarring process. This is partly due to the absence of physiologically relevant, easily operable, and low-cost in vitro models, which are of the utmost importance to uncover pathological mechanisms and highlight possible targets for anti-fibrotic therapies. In classic models, fibrotic features are usually obtained using substrates with scar mimicking stiffness and/or supplementation of morphogens such as transforming growth factor ß1 (TGF-ß1). Qualities such as the interplay between activated fibroblasts (FBs) and cardiomyocytes (CMs), or the mechanically active, three-dimensional (3D) environment, are, however, neglected or obtained at the expense of the number of experimental replicates achievable. To overcome these shortcomings, we engineered a micro-physiological system (MPS) where multiple 3D cardiac micro-tissues can be subjected to cyclical stretching simultaneously. Up to six different biologically independent samples are incorporated in a single device, increasing the experimental throughput and paving the way for higher yielding drug screening campaigns. The newly developed MPS was used to co-culture different ratios of neonatal rat CMs and FBs, investigating the role of CMs in the modulation of fibrosis traits, without the addition of morphogens, and in soft substrates. The expression of contractile stress fibers and of degradative enzymes, as well as the deposition of fibronectin and type I collagen were superior in microtissues with a low amount of CMs. Moreover, high CM-based microconstructs simulating a ratio similar to that of healthy tissues, even if subjected to both cyclic stretch and TGF-ß1, did not show any of the investigated fibrotic signs, indicating a CM fibrosis modulating effect. Overall, this in vitro fibrosis model could help to uncover new pathological aspects studying, with mid-throughput and in a mechanically active, physiologically relevant environment, the crosstalk between the most abundant cell types involved in fibrosis.

Intervertebral Disc-on-a-Chip as Advanced In Vitro Model for Mechanobiology Research and Drug Testing: A Review and Perspective.

Discogenic back pain is one of the most diffused musculoskeletal pathologies and a hurdle to a good quality of life for millions of people. Existing therapeutic options are exclusively directed at reducing symptoms, not at targeting the underlying, still poorly understood, degenerative processes. Common intervertebral disc (IVD) disease models still do not fully replicate the course of degenerative IVD disease. Advanced disease models that incorporate mechanical loading are needed to investigate pathological causes and processes, as well as to identify therapeutic targets. Organs-on-chip (OoC) are microfluidic-based devices that aim at recapitulating tissue functions in vitro by introducing key features of the tissue microenvironment (e.g., 3D architecture, soluble signals and mechanical conditioning). In this review we analyze and depict existing OoC platforms used to investigate pathological alterations of IVD cells/tissues and discuss their benefits and limitations. Starting from the consideration that mechanobiology plays a pivotal role in both IVD homeostasis and degeneration, we then focus on OoC settings enabling to recapitulate physiological or aberrant mechanical loading, in conjunction with other relevant features (such as inflammation). Finally, we propose our view on design criteria for IVD-on-a-chip systems, offering a future perspective to model IVD mechanobiology.

Contrast-Induced Nephropathy in Patients Undergoing Staged Versus Concomitant Transcatheter Aortic Valve Implantation and Coronary Procedures.

Background The impact of staged versus concomitant coronary procedures on renal function in patients with aortic stenosis undergoing transcatheter aortic valve implantation (TAVI) remains unclear. Methods and Results Three-hundred thirty-nine patients undergoing coronary procedures and TAVI as a staged strategy (160, 47.2%) or concomitant strategy (179, 52.8%) were retrospectively analyzed. Contrast-induced acute kidney injury (CI-AKI) occurred in 49 patients in the staged strategy group (30.6%) and in 18 patients (10.1%) in the concomitant strategy group (P<0.001). Among the staged strategy group, 25 (15.6%) patients developed CI-AKI after coronary angiography or percutaneous coronary intervention, 17 (10.6%) after TAVI, and 7 (4.3%) after both the procedures. Staged strategy was associated with a higher risk of CI-AKI (odds ratio, 3.948; P<0.001) after adjustment for multiple confounders and regardless of the baseline renal function (P for interaction=0.4) when compared with the concomitant strategy. At a median follow-up of 24.0 months (3.0-35.3), CI-AKI was not associated with sustained renal injury (P=0.794), irrespective of the adopted strategy. The concomitant strategy did not impact the overall early safety at 30 days follow-up after TAVI compared to the staged strategy (P=0.609). Conclusions Performing coronary procedures with a staged strategy before TAVI was associated with a higher risk of CI-AKI compared with a concomitant strategy. Moreover, a concomitant strategy did not increase the risk of procedure-related complications.