Development of a Novel Hierarchically Biofabricated Blood Vessel Mimic Decorated with Three Vascular Cell Populations for the Reconstruction of Small-Diameter Arteries.

The availability of grafts to replace small-diameter arteries remains an unmet clinical need. Here, the validated methodology is reported for a novel hybrid tissue-engineered vascular graft that aims to match the natural structure of small-size arteries. The blood vessel mimic (BVM) comprises an internal conduit of co-electrospun gelatin and polycaprolactone (PCL) nanofibers (corresponding to the tunica intima of an artery), reinforced by an additional layer of PCL aligned fibers (the internal elastic membrane). Endothelial cells are deposited onto the luminal surface using a rotative bioreactor. A bioprinting system extrudes two concentric cell-laden hydrogel layers containing respectively vascular smooth muscle cells and pericytes to create the tunica media and adventitia. The semi-automated cellularization process reduces the production and maturation time to 6 days. After the evaluation of mechanical properties, cellular viability, hemocompatibility, and suturability, the BVM is successfully implanted in the left pulmonary artery of swine. Here, the BVM showed good hemostatic properties, capability to withstand blood pressure, and patency at 5 weeks post-implantation. These promising data open a new avenue to developing an artery-like product for reconstructing small-diameter blood vessels.

Machine Learning and Statistical Shape Modelling Methodologies to Assess Vascular Morphology before and after Aortic Valve Replacement.

Introduction: Statistical shape modelling (SSM) is used to analyse morphology, discover qualitatively and quantitatively unique shape features within a population, and generate mean shapes and shape modes that show morphological variability. Hierarchical agglomerative clustering is a machine learning analysis used to identify subgroups within a given population in relation to shape features. We tested the application of both methods in the clinically relevant scenario of patients undergoing aortic valve repair (AVR). Every year, around 5000 patients undergo surgical AVR in the UK. Aims: Evaluate aortic morphology and identify subgroups amongst patients who had undergone AVR, including Ozaki, Ross, and valve-sparing procedures using SSM and unsupervised hierarchical clustering analysis. This methodological framework can evaluate both pre- and post-surgical variability across subgroups undergoing different surgeries. Methods: Pre- (n = 47) and post- (n = 35) operative three-dimensional (3D) aortic models were reconstructed from computed tomography (CT) and cardiac magnetic resonance (CMR) images. Computational analyses for SSM and hierarchical clustering were run separately for the two subgroups, assessing (a) ascending aorta only and (b) the whole aorta. This allows for exploring possible variations in morphological classification related to the input shape. Results: Most patients in the Ross procedure subgroup exhibited differences in aortic morphology from other subgroups, including an elongated ascending and wide aortic arch pre-operatively, and an elongated ascending aorta with a slightly enlarged sinus post-operatively. In hierarchical clustering, the Ross aortas also appeared to cluster together compared to the other surgical procedures, both pre-operatively and post-operatively. There were significant differences between clusters in terms of clustering distance in the pre-operative analyses (p = 0.003 for ascending aortas, p = 0.016 for whole aortas). There were no significant differences between the clusters in post-operative analyses (p = 0.47 for ascending, p = 0.19 for whole aorta). Conclusions: We demonstrated the feasibility of evaluating aortic morphology before and after different aortic valve surgeries using SSM and hierarchical clustering. This framework could be used to further explore shape features associated with surgical decision-making pre-operatively and, importantly, to identify subgroups whose morphology is associated with poorer clinical outcomes post-operatively. Statistical shape modelling (SSM) and unsupervised hierarchical clustering are two statistical methods that can be used to assess morphology, show morphological variations, with the latter being able to identify subgroups within a population. These methods have been applied to the population of aortic valve replacement (AVR) patients since there are different surgical procedures (traditional AVR, Ozaki, Ross, and valve-sparing). The aim is to evaluate aortic morphology and identify subgroups within this population before and after surgery. Computed tomography and cardiac magnetic resonance images were reconstructed into 3D models of the ascending aorta and whole aorta, which were then input into SSM and hierarchical clustering. The results show that the Ross aortic morphology is quite different from the other aortas. The clustering did not classify the aortas based on the surgical procedures; however, most of the Ross group did cluster together, indicating low variability within this surgical group.

Protocol to decellularize porcine right ventricular outflow tracts using a 3D printed flow chamber.

Surgical treatment of pediatric congenital heart disease with tissue grafts is a lifesaving intervention. Decellularization to reduce immunogenicity of tissue grafts is an increasingly popular alternative to glutaraldehyde fixation. Here, we present a protocol to decellularize porcine right ventricular outflow tracts using a 3D printed flow chamber. We describe steps for 3D printing the flow rig, preparing porcine tissue, and using the flow rig to utilize shear forces for decellularization. We then detail procedures for characterizing the acellular scaffold. For complete details on the use and execution of this protocol, please refer to Vafaee et al.1.

Surgical Patching in Congenital Heart Disease: The Role of Imaging and Modelling.

In congenital heart disease, patches are not tailored to patient-specific anatomies, leading to shape mismatch with likely functional implications. The design of patches through imaging and modelling may be beneficial, as it could improve clinical outcomes and reduce the costs associated with redo procedures. Whilst attention has been paid to the material of the patches used in congenital surgery, this review outlines the current knowledge on this subject and isolated experimental work that uses modelling and imaging-derived information (including 3D printing) to inform the design of the surgical patch.

The Role of Immersive Virtual Reality and Augmented Reality in Medical Communication: A Scoping Review.

Communication between clinicians and patients and communication within clinical teams is widely recognized as a tool through which improved patient outcomes can be achieved. As emerging technologies, there is a notable lack of commentary on the role of immersive virtual reality (VR) and augmented reality (AR) in enhancing medical communication. This scoping review aims to map the current landscape of literature on this topic and highlights gaps in the evidence to inform future endeavors. A comprehensive search strategy was conducted across 3 databases (PubMed, Web of Science, and Embase), yielding 1000 articles, of which 623 were individually screened for relevance. Ultimately, 22 articles were selected for inclusion and review. Similarities across the cohort of studies included small sample sizes, observational study design, use of questionnaires, and more VR studies than AR. The majority of studies found these technologies to improve medical communication, although user tolerability limitations were identified. More studies are required, presenting more robust findings, in order to draw more definitive conclusions and stronger recommendations for use of immersive VR/AR in clinical environments.

"Please keep on beating"-Participation in a Creative Workshop Offers Unexpected Benefits to Women With Takotsubo Cardiomyopathy.

Takotsubo cardiomyopathy (TCM) or "broken heart syndrome" is a rare condition that is more common in women than men, particularly those who are postmenopausal. It mimics a myocardial infarction and psychological factors have been implicated in its etiology as well as being consequences of its presentation. As part of a public engagement project we brought together 8 women (of 12 invited) previously diagnosed with TCM to facilitate a discussion, through participation in a creative workshop-based process, about their illness experience, how they made sense of it, and the meaning it had for them in their lives, and to identify areas of unmet need. Through a range of creative activities we identified that participants had high levels of unmet need in terms of information and psychosocial support. All participants enjoyed the creative process and meeting other people with a diagnosis of TCM. The workshop overall was perceived as empowering. Exploring patient narratives during artist-facilitated workshops is one approach for providing the first steps to addressing unmet need, although the importance of ensuring psychological safety cannot be over-stated.

Reporting involvement activities with children and young people in paediatric research: a framework analysis.

BACKGROUND: The active involvement of patients and the public in the design and delivery of health research has been increasingly encouraged, if not enforced. Knowledge of how this is realised in practice, especially where children and young people (CYP) are concerned, is limited, partly due to the low level of reporting of patient and public involvement (PPI) in general. The aim of this work was to assess how researchers funded by the National Institute for Health and Care Research (NIHR) report the involvement of CYP in the design and conduct of child health research to better understand the opportunities offered to CYP, and the realities of involvement in practice. METHODS: A participation matrix, analysis framework and accompanying tools were adapted from existing frameworks, including a child-rights informed framework, the Guidance for Reporting Involvement of Patients and the Public Checklist Short Form (GRIPP2SF), and NIHR reporting expectations. Child-focused research reports were identified from the NIHR Journals Library, including any interventional or observational study involving CYP aged 0-< 24 years. In two co-design workshops with healthcare professionals and CYP, we tested and refined the participation matrix, analysis framework and accompanying tools. RESULTS: Only thirty-two NIHR reports out of 169 (19%) were identified as relevant and included reporting of PPI with CYP. We identified significant variability in the way PPI with CYP was reported. Only 4/32 (12%) reports fully met NIHR (and GRIPP2SF) reporting criteria. Only 3/32 (9%) reports formally evaluated or self-reflected on PPI activities with CYP, whilst 15/32 (47%) provided minimal information about CYP involvement. The most common approach to involving CYP (23/32, 72%) was through the medium of existing groups or networks. CONCLUSION: Despite the NIHR's commitment to increase the quality, transparency, and consistency of reporting PPI, the reporting of involvement with CYP remains sub-optimal. Neglecting to report key details of involvement methods and impacts deprives the research community of knowledge to advance the field of delivering 'meaningful' PPI with CYP. Practical guidance on how researchers can report the processes and outputs of CYP involvement more rigorously may help child health researchers to involve them more meaningfully. This research offers practical tools informed by CYP to aid the reporting process.

BACKGROUND: Children and young people can (and should) be involved in the design of child-health research. How this works in practice is limited due to the low-level reporting of involvement activities. AIM: We wanted to understand how researchers funded by the National Institute for Health and Care Research (NIHR) are reporting involvement activities with children and young people in child-health research. WHAT WE DID AND HOW WE DID IT: A team of healthcare researchers (working in child-health research), a parent, and children and young people adapted existing tools to assess how the involvement of children and young people is reported in child-health research. We looked at reports in an online library to see how researchers are meeting the reporting guidelines set by the NIHR. FINDINGS: Despite the reporting guidelines provided by the NIHR, only four out of thirty-two reports followed this. It is still unclear who is involved, why, and what outcomes and impact involvement has on the research process, on children and young people and/or on researchers. This is a missed opportunity to learn from previous experiences and to build on good practice. Further work is needed to understand why and how the NIHR, and other funders of health research collect such information, and what their plans are for sharing the findings with the wider research community.

Feasibility of Wave Intensity Analysis from 4D Cardiovascular Magnetic Resonance Imaging Data.

Congenital heart defects (CHD) introduce haemodynamic changes; e.g., bicuspid aortic valve (BAV) presents a turbulent helical flow, which activates aortic pathological processes. Flow quantification is crucial for diagnostics and to plan corrective strategies. Multiple imaging modalities exist, with phase contrast magnetic resonance imaging (PC-MRI) being the current gold standard; however, multiple predetermined site measurements may be required, while 4D MRI allows for measurements of area (A) and velocity (U) in all spatial dimensions, acquiring a single volume and enabling a retrospective analysis at multiple locations. We assessed the feasibility of gathering hemodynamic insight into aortic hemodynamics by means of wave intensity analysis (WIA) derived from 4D MRI. Data were collected in n = 12 BAV patients and n = 7 healthy controls. Following data acquisition, WIA was successfully derived at three planes (ascending, thoracic and descending aorta) in all cases. The values of wave speed were physiological and, while the small sample limited any clinical interpretation of the results, the study shows the possibility of studying wave travel and wave reflection based on 4D MRI. Below, we demonstrate for the first time the feasibility of deriving wave intensity analysis from 4D flow data and open the door to research applications in different cardiovascular scenarios.

Perspectives on medical 3D printing at the point-of-care from the new European 3D Printing Special Interest Group.

This editorial presents the vision for the newly formed (2022) European 3D Special Interest Group (EU3DSIG) in the landscape of medical 3D printing. There are four areas of work identified by the EU3DSIG in the current landscape, namely: 1) creating and fostering communication channels among researches, clinicians and industry, 2) generating awareness of hospitals point-of-care 3D technologies; 3) knowledge sharing and education; 4) regulation, registry and reimbursement models.

Assessment of post-infarct ventricular septal defects through 3D printing and statistical shape analysis.

Background: Post-infarct ventricular septal defect (PIVSD) is a serious complication of myocardial infarction. We evaluated 3D-printing models in PIVSD clinical assessment and the feasibility of statistical shape modeling for morphological analysis of the defects. Methods: Models (n = 15) reconstructed from computed tomography data were evaluated by clinicians (n = 8). Statistical shape modeling was performed on 3D meshes to calculate the mean morphological configuration of the defects. Results: Clinicians' evaluation highlighted the models' utility in displaying defects for interventional/surgical planning, education/training and device development. However, models lack dynamic representation. Morphological analysis was feasible and revealed oval-shaped (n = 12) and complex channel-like (n = 3) defects. Conclusion: 3D-PIVSD models can complement imaging data for teaching and procedural planning. Statistical shape modeling is feasible in this scenario.

Following heart attacks, the heart muscle becomes scarred and weaker, making it prone to tearing under high pressures. These tears are known as 'post-infarct ventricular septal defects'. Their shape varies greatly as the heart beats. The approach to fixing these can range from plugging them with a device or patching them by open heart surgery. We created 15 3D-printed models of hearts with these kinds of defects and made digital reconstructions of the tears to see the different sizes/shapes that they can have. Doctors agreed that 3D-printed models could help in planning repairs and training other doctors. The digital reconstructions of the tears showed that many were round, but some had irregular shapes which would mean devices used to fix them may not fit.

Biological Scaffolds for Congenital Heart Disease.

Congenital heart disease (CHD) is the most predominant birth defect and can require several invasive surgeries throughout childhood. The absence of materials with growth and remodelling potential is a limitation of currently used prosthetics in cardiovascular surgery, as well as their susceptibility to calcification. The field of tissue engineering has emerged as a regenerative medicine approach aiming to develop durable scaffolds possessing the ability to grow and remodel upon implantation into the defective hearts of babies and children with CHD. Though tissue engineering has produced several synthetic scaffolds, most of them failed to be successfully translated in this life-endangering clinical scenario, and currently, biological scaffolds are the most extensively used. This review aims to thoroughly summarise the existing biological scaffolds for the treatment of paediatric CHD, categorised as homografts and xenografts, and present the preclinical and clinical studies. Fixation as well as techniques of decellularisation will be reported, highlighting the importance of these approaches for the successful implantation of biological scaffolds that avoid prosthetic rejection. Additionally, cardiac scaffolds for paediatric CHD can be implanted as acellular prostheses, or recellularised before implantation, and cellularisation techniques will be extensively discussed.

Sex differences in patients with acute coronary syndromes and non-obstructive coronary arteries: Presentation and outcome.

BACKGROUND: A substantial number of patients present with a suspected ACS and non-obstructive coronary arteries; sex differences in these patients are not well understood. This study aims to evaluate the impact of sex on clinical presentation and outcome in patients with suspected acute coronary syndrome (ACS) and non-obstructive coronary arteries with a final diagnosis confirmed by cardiovascular magnetic resonance imaging (CMR). METHODS: Consecutive patients with ACS and non-obstructive coronary arteries (n = 719) with an unclear cause from a single tertiary centre who were referred for CMR were included. The primary endpoint was all-cause mortality. RESULTS: CMR was performed at a median time of 30 days after presentation and identified a diagnosis in 74% of patients. All-cause mortality was 9.5% over a median follow up of 4.9 years, with no significant difference between sexes (8.8% versus 10.1%; p = 0.456). Men were more likely to have non-ischaemic aetiology on CMR than women (55% v 41%, p < 0.001), but were equally likely to have an ischaemic cause (25% v 27%, p = 0.462). Age group (HR 1.58, p < 0.001) and LV ejection fraction (HR 0.98, p = 0.023) were independent predictors of mortality. CONCLUSIONS: There is no difference in all-cause mortality between sexes in patients presenting with suspected ACS and non-obstructive coronary arteries.

A Segmental Approach from Molecular Profiling to Medical Imaging to Study Bicuspid Aortic Valve Aortopathy.

Bicuspid aortic valve (BAV) patients develop ascending aortic (AAo) dilation. The pathogenesis of BAV aortopathy (genetic vs. haemodynamic) remains unclear. This study aims to identify regional changes around the AAo wall in BAV patients with aortopathy, integrating molecular data and clinical imaging. BAV patients with aortopathy (n = 15) were prospectively recruited to surgically collect aortic tissue and measure molecular markers across the AAo circumference. Dilated (anterior/right) vs. non-dilated (posterior/left) circumferential segments were profiled for whole-genomic microRNAs (next-generation RNA sequencing, miRCURY LNA PCR), protein content (tandem mass spectrometry), and elastin fragmentation and degeneration (histomorphometric analysis). Integrated bioinformatic analyses of RNA sequencing and proteomic datasets identified five microRNAs (miR-128-3p, miR-210-3p, miR-150-5p, miR-199b-5p, and miR-21-5p) differentially expressed across the AAo circumference. Among them, three miRNAs (miR-128-3p, miR-150-5p, and miR-199b-5p) were predicted to have an effect on eight common target genes, whose expression was dysregulated, according to proteomic analyses, and involved in the vascular-endothelial growth-factor signalling, Hippo signalling, and arachidonic acid pathways. Decreased elastic fibre levels and elastic layer thickness were observed in the dilated segments. Additionally, in a subset of patients n = 6/15, a four-dimensional cardiac magnetic resonance (CMR) scan was performed. Interestingly, an increase in wall shear stress (WSS) was observed at the anterior/right wall segments, concomitantly with the differentially expressed miRNAs and decreased elastic fibres. This study identified new miRNAs involved in the BAV aortic wall and revealed the concomitant expressional dysregulation of miRNAs, proteins, and elastic fibres on the anterior/right wall in dilated BAV patients, corresponding to regions of elevated WSS.

Analysing functional implications of differences in left ventricular morphology using statistical shape modelling.

Functional implications of left ventricular (LV) morphological characterization in congenital heart disease are not widely explored. This study qualitatively and quantitatively assessed LV shape associations with a) LV function and b) thoracic aortic morphology in patients with aortic coarctation (CoA) with/without bicuspid aortic valve (BAV), and healthy controls. A statistical shape modelling framework was employed to analyse three-dimensional (3D) LV shapes from cardiac magnetic resonance (CMR) data in isolated CoA (n = 25), CoA + BAV (n = 30), isolated BAV (n = 30), and healthy controls (n = 25). Average 3D templates and deformations were computed. Correlations between shape data and CMR-derived morphometric parameters (i.e., sphericity, conicity) or global and apical strain values were assessed to elucidate possible functional implications. The relationship between LV shape features and arch architecture was also explored. The LV template was shorter and more spherical in CoA patients. Sphericity was overall associated with global and apical radial (p = 0.001, R2 = 0.09; p < 0.0001, R2 = 0.17) and circumferential strain (p = 0.001, R2 = 0.10; p = 0.04, R2 = 0.04), irrespective of the presence of aortic stenosis and/or regurgitation and controlling for age and hypertension status. LV strain was not associated with arch architecture. Differences in LV morphology were observed between CoA and BAV patients. Increasing LV sphericity was associated with reduced strain, independent of aortic arch architecture and functional aortic valve disease.

Prospective multiparametric CMR characterization and MicroRNA profiling of anthracycline cardiotoxicity: A pilot translational study.

Background: Anthracycline cardiotoxicity is a significant clinical challenge. Biomarkers to improve risk stratification and identify early cardiac injury are required. Objectives: The purpose of this pilot study was to prospectively characterize anthracycline cardiotoxicity using cardiovascular magnetic resonance (CMR), echocardiography and MicroRNAs (MiRNAs), and identify baseline predictors of LVEF recovery. Methods: Twenty-four patients (age 56 range 18-75 years; 42 % female) with haematological malignancy scheduled to receive anthracycline chemotherapy (median dose 272 mg/m2 doxorubicin equivalent) were recruited and evaluated at three timepoints (baseline, completion of chemotherapy, and 6 months after completion of chemotherapy) with multiparametric 1.5 T CMR, echocardiography and circulating miRNAs sequencing. Results: Seventeen complete datasets were obtained. CMR left ventricular ejection fraction (LVEF) fell significantly between baseline and completion of chemotherapy (61 ± 3 vs 53 ± 3 %, p < 0.001), before recovering significantly at 6-month follow-up (55 ± 3 %, p = 0.018). Similar results were observed for 3D echocardiography-derived LVEF and CMR-derived longitudinal, circumferential and radial feature-tracking strain. Patients were divided into tertiles according to LVEF recovery (poor recovery, partial recovery, good recovery). CMR-derived mitral annular plane systolic excursion (MAPSE) was significantly different at baseline in patients exhibiting poor LVEF recovery (11.7 ± 1.5 mm) in comparison to partial recovery (13.7 ± 2.7 mm), and good recovery (15.7 ± 3.1 mm; p = 0.028). Furthermore, baseline miRNA-181-5p and miRNA-221-3p expression were significantly higher in this group. T2 mapping increased significantly on completion of chemotherapy compared to baseline (54.0 ± 4.6 to 57.8 ± 4.9 ms, p = 0.001), but was not predictive of LVEF recovery. No changes to LV mass, extracellular volume fraction, T1 mapping or late gadolinium enhancement were observed. Conclusions: Baseline CMR-derived MAPSE, circulating miRNA-181-5p, and miRNA-221-3p were associated with poor recovery of LVEF 6 months after completion of anthracycline chemotherapy, suggesting their potential predictive role in this context. T2 mapping increased significantly on completion of chemotherapy but was not predictive of LVEF recovery.

Relationship between Pulmonary Regurgitation and Ventriculo-Arterial Interactions in Patients with Post-Early Repair of Tetralogy of Fallot: Insights from Wave-Intensity Analysis.

This study aimed to investigate the effect of pulmonary regurgitation (PR) on left ventricular ventriculo-arterial (VA) coupling in patients with repaired tetralogy of Fallot (ToF). It was hypothesised that increasing PR severity results in a smaller forward compression wave (FCW) peak in the aortic wave intensity, because of right-to-left ventricular interactions. The use of cardiovascular magnetic resonance (CMR)-derived wave-intensity analysis provided a non-invasive comparison between patients with varying PR degrees. A total of n = 201 patients were studied and both hemodynamic and wave-intensity data were compared. Wave-intensity peaks and areas of the forward compression and forward expansion waves were calculated as surrogates of ventricular function. Any extent of PR resulted in a significant reduction in the FCW peak. A correlation was found between aortic distensibility and the FCW peak, suggesting unfavourable (VA) coupling in patients that also present stiffer ascending aortas. Data suggest that VA coupling is affected by increased impedance.

Peak Troponin and CMR to Guide Management in Suspected ACS and Nonobstructive Coronary Arteries.

BACKGROUND: Patients presenting with acute coronary syndrome (ACS) and nonobstructive coronary arteries are a diagnostic dilemma. Cardiac magnetic resonance (CMR) has an overall diagnostic yield of ∼75%; however, in ∼25% of patients, CMR does not identify any myocardial injury. Identifying the underlying diagnosis has important clinical implications for patients' management and outcome. OBJECTIVES: The authors sought to assess whether the combination of CMR and peak troponin levels in patients with ACS and nonobstructive coronary arteries would lead to increased diagnostic yield. METHODS: Consecutive patients with ACS and nonobstructive coronary arteries without an obvious cause underwent CMR. The primary endpoint of the study was the diagnostic yield of CMR. The Youden index was used to find the optimal diagnostic cut point for peak troponin T to combine with CMR to improve diagnostic yield. Logistic or Cox regression models were used to estimate predictors of a diagnosis by CMR. RESULTS: A total of 719 patients met the inclusion criteria. The peak troponin T threshold for optimal diagnostic sensitivity and specificity was 211 ng/L. Overall, CMR has a diagnostic yield of 74%. CMR performed <14 days from presentation and with a peak troponin of ≥211 ng/L (n = 198) leads to an improved diagnostic yield (94% vs 72%) compared with CMR performed ≥14 days (n = 245). When CMR was performed <14 days and with a peak troponin of <211 ng/L, the diagnostic yield was 76% (n = 86) compared with 53% (n = 190) when performed ≥14 days. An increase in 1 peak troponin decile increases the odds of the CMR identifying a diagnosis by 20% (OR: 1.20; P = 0.008, 95% CI: 1.05-1.36). CONCLUSIONS: The combination of CMR performed <14 days from presentation and peak troponin T ≥211 ng/L leads to a very high diagnostic yield (94%) on CMR. The diagnostic yield remains high (72%) even when CMR is performed ≥14 days from presentation, but reduces to 53% when peak troponin T was <211 ng/L.

Isolating the Effect of Arch Architecture on Aortic Hemodynamics Late After Coarctation Repair: A Computational Study.

Objectives: Effective management of aortic coarctation (CoA) affects long-term cardiovascular outcomes. Full appreciation of CoA hemodynamics is important. This study aimed to analyze the relationship between aortic shape and hemodynamic parameters by means of computational simulations, purposely isolating the morphological variable. Methods: Computational simulations were run in three aortic models. MRI-derived aortic geometries were generated using a statistical shape modeling methodology. Starting from n = 108 patients, the mean aortic configuration was derived in patients without CoA (n = 37, "no-CoA"), with surgically repaired CoA (n = 58, "r-CoA") and with unrepaired CoA (n = 13, "CoA"). As such, the aortic models represented average configurations for each scenario. Key hemodynamic parameters (i.e., pressure drop, aortic velocity, vorticity, wall shear stress WSS, and length and number of strong flow separations in the descending aorta) were measured in the three models at three time points (peak systole, end systole, end diastole). Results: Comparing no-CoA and CoA revealed substantial differences in all hemodynamic parameters. However, simulations revealed significant increases in vorticity at the site of CoA repair, higher WSS in the descending aorta and a 12% increase in power loss, in r-CoA compared to no-CoA, despite no clinically significant narrowing (CoA index >0.8) in the r-CoA model. Conclusions: Small alterations in aortic morphology impact on key hemodynamic indices. This may contribute to explaining phenomena such as persistent hypertension in the absence of any clinically significant narrowing. Whilst cardiovascular events in these patients may be related to hypertension, the role of arch geometry may be a contributory factor.

What Arts-and-Health Practices Teach Us About Participation, Re-presentation, and Risk.

This article explores the implications of risk in arts-and-health collaborations that represent illness narratives for the purpose of engaging the public. Based on an artist's, bioengineer's, and health psychologist's reflections from pediatric and adult group workshop practice settings, this article canvasses 8 dimensions of risk that deserve ethical attention.

Feasibility of a longitudinal statistical atlas model to study aortic growth in congenital heart disease.

Studying anatomical shape progression over time is of utmost importance to refine our understanding of clinically relevant processes. These include vascular remodeling, such as aortic dilation, which is particularly important in some congenital heart defects (CHD). A novel methodological framework for three-dimensional shape analysis has been applied for the first time in a CHD scenario, i.e., bicuspid aortic valve (BAV) disease, the most common CHD. Three-dimensional aortic shapes (n = 94) reconstructed from cardiovascular magnetic resonance imaging (MRI) data as surface meshes represented the input for a longitudinal atlas model, using multiple scans over time (n = 2-4 per patient). This model relies on diffeomorphism transformations in the absence of point-to-point correspondence, and on the right combination of initialization, estimation and registration parameters. We computed the shape trajectory of an average disease progression in our cohort, as well as time-dependent parameters, geometric variations and the average shape of the population. Results cover a spatiotemporal spectrum of visual and numerical information that can be further used to run clinical associations. This proof-of-concept study demonstrates the feasibility of applying advanced statistical shape models to track disease progression and stratify patients with CHD.