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Biobanking in health care has evolved over the last few decades from simple biological sample repositories to complex and dynamic units with multi‐organizational infrastructure networks and has become an essential tool for modern medical research. Cardiovascular tissue biobanking provides a unique opportunity to utilize cardiac and vascular samples for translational research into heart failure and other related pathologies. Current techniques for diagnosis, classification, and treatment monitoring of cardiac disease relies primarily on interpretation of clinical signs, imaging, and blood biomarkers. Further research at the disease source (i.e. myocardium and blood vessels) has been limited by a relative lack of access to quality human cardiac tissue and the inherent shortcomings of most animal models of heart disease. In this review, we describe a model for cardiovascular tissue biobanking and databasing, and its potential to facilitate basic and translational research. We share techniques to procure endocardial samples from patients with hypertrophic cardiomyopathy, heart failure with reduced ejection fraction, and heart failure with preserved ejection fraction, in addition to aortic disease samples. We discuss some of the issues with respect to data collection, privacy, biobank consent, and the governance of tissue biobanking. The development of tissue biobanks as described here has significant scope to improve and facilitate translational research in multi‐omic fields such as genomics, transcriptomics, proteomics, and metabolomics. This research heralds an era of precision medicine, in which patients with cardiovascular pathology can be provided with optimized and personalized medical care for the treatment of their individual phenotype.

Background: The primary objective of this review was to explore the contribution of oxidative stress to the pathogenesis of genetically-triggered thoracic aortic aneurysm (TAA). Genetically-triggered TAAs manifest substantial variability in onset, progression, and risk of aortic dissection, posing a significant clinical management challenge. There is a need for non-invasive biomarkers that predict the natural course of TAA and therapeutics that prevent aneurysm progression. Methods: An online systematic search was conducted within PubMed, MEDLINE, Scopus and ScienceDirect databases using keywords including: oxidative stress, ROS, nitrosative stress, genetically triggered thoracic aortic aneurysm, aortic dilatation, aortic dissection, Marfan syndrome, Bicuspid Aortic Valve, familial TAAD, Loeys Dietz syndrome, and Ehlers Danlos syndrome. Results: There is extensive evidence of oxidative stress and ROS imbalance in genetically triggered TAA. Sources of ROS imbalance are variable but include dysregulation of redox mediators leading to either insufficient ROS removal or increased ROS production. Therapeutic exploitation of redox mediators is being explored in other cardiovascular conditions, with potential application to TAA warranting further investigation. Conclusion: Oxidative stress occurs in genetically triggered TAA, but the precise contribution of ROS to pathogenesis remains incompletely understood. Further research is required to define causative pathological relationships in order to develop therapeutic options.

It is well-established that variations of a CGG repeat expansion in the gene FMR1, which encodes the fragile-X mental retardation protein (FMRP), cause the neurocognitive disorder, fragile-X syndrome (FXS). However, multiple observations suggest a general and complex regulatory role of FMRP in processes outside the brain: (1) FMRP is ubiquitously expressed in the body, suggesting it functions in multiple organ systems; (2) patients with FXS can exhibit a physical phenotype that is consistent with an underlying abnormality in connective tissue; (3) different CGG repeat expansion lengths in FMR1 result in different clinical outcomes due to different pathogenic mechanisms; (4) the function of FMRP as an RNA-binding protein suggests it has a general regulatory role. This review details the complex nature of FMRP and the different CGG repeat expansion lengths and the evidence supporting the essential role of the protein in a variety of biological and pathological processes.

Summary Introduction Familial hypercholesterolaemia (FH) is a common, heritable and preventable cause of premature coronary artery disease, with significant potential for positive impact on public health and healthcare savings. New clinical practice recommendations are presented in an abridged guidance to assist practitioners in enhancing the care of all patients with FH. Main recommendations Core recommendations are made on the detection, diagnosis, assessment and management of adults, children and adolescents with FH. There is a key role for general practitioners (GPs) working in collaboration with specialists with expertise in lipidology. Advice is given on genetic and cholesterol testing and risk notification of biological relatives undergoing cascade testing for FH; all healthcare professionals should develop skills in genomic medicine. Management is under-pinned by the precepts of risk stratification, adherence to healthy lifestyles, treatment of non-cholesterol risk factors, and appropriate use of low-density lipoprotein (LDL)-cholesterol lowering therapies, including statins, ezetimibe and proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors. Recommendations on service design are provided in the full guidance. Potential impact on care of FH These recommendations need to be utilised using judicious clinical judgement and shared decision making with patients and families. Models of care need to be adapted to both local and regional needs and resources. In Australia new government funded schemes for genetic testing and use of PCSK9 inhibitors, as well as the National Health Genomics Policy Framework, will enable adoption of these recommendations. A broad implementation science strategy is, however, required to ensure that the guidance translates into benefit for all families with FH.

Familial hypercholesterolaemia (FH) is a dominant and highly penetrant monogenic disorder present from birth that markedly elevates plasma low-density lipoprotein (LDL)-cholesterol concentration and, if untreated, leads to premature atherosclerosis and coronary artery disease (CAD). There are approximately 100,000 people with FH in Australia. However, an overwhelming majority of those affected remain undetected and inadequately treated, consistent with FH being a leading challenge for public health genomics. To further address the unmet need, we provide an updated guidance, presented as a series of systematically collated recommendations, on the care of patients and families with FH. These recommendations have been informed by an exponential growth in published works and new evidence over the last 5 years and are compatible with a contemporary global call to action on FH. Recommendations are given on the detection, diagnosis, assessment and management of FH in adults and children. Recommendations are also made on genetic testing and risk notification of biological relatives who should undergo cascade testing for FH. Guidance on management is based on the concepts of risk re-stratification, adherence to heart healthy lifestyles, treatment of non-cholesterol risk factors, and safe and appropriate use of LDL-cholesterol lowering therapies, including statins, ezetimibe, proprotein convertase subtilisin/kexin type 9 inhibitors and lipoprotein apheresis. Broad recommendations are also provided for the organisation and development of health care services. Recommendations on best practice need to be underpinned by good clinical judgment and shared decision making with patients and families. Models of care for FH need to be adapted to local and regional health care needs and available resources. A comprehensive and realistic implementation strategy, informed by further research, including assessments of cost-benefit, will be required to ensure that this new guidance benefits all Australian families with or at risk of FH.

Background Non-syndromal thoracic aortic aneurysm and dissection (ns-TAAD) is a genetic aortopathy, with uncertain incidence. This study documented the incidence of ns-TAAD and outcomes of family screening over 15years. Methods Consecutive series of 2385 patients with aortic disease in prospective registry (2000 to 2014), including 675 undergoing surgery. Diagnosis of ns-TAAD included family history, aortic imaging, tissue pathology and mutation testing. Screening was offered to relatives of ns-TAAD probands, with follow-up for affected individuals. Results There were 270 ns-TAAD probands (74% males), including 116 (43%) presenting with aortic dissection. Among surgical cases, a diagnosis of ns-TAAD was established for 116 (17%). Age of probands was 50.4±14.1years, with aortic diameter of 51±12mm. Screening of 581 at-risk relatives identified 216 new ns-TAAD cases (detection rate=37%). Among 71 probands with known family history, screening identified 130 new affected relatives and among 53 probands with no family history, screening identified 86 new affected relatives. Mean age of new affected relatives at diagnosis was 44±18years, with aortic diameter of 42±7mm, including 42 with diameter>50mm. Ten-year mortality was similar for probands without dissection (7.7±3.1%) and new affected relatives (11.4±4.0%) but greater for probands surviving initial dissection (27.6±7.8%, p=0.003). Conclusions Up to 1 in 6 patients undergoing aortic surgery have features of ns-TAAD, frequently presenting as aortic dissection but at later age than other genetic aortopathies. Family screening identifies affected relatives in up to half of ns-TAAD probands, many of whom already have significant aortic dilatation.

Genetically triggered thoracic aortic aneurysms (TAAs) are usually considered to exhibit minimal levels of inflammation. However, emerging data demonstrate that specific features of an inflammatory response can be observed in TAA, and that the extent of the inflammatory response can be correlated with the severity, in both mouse models and in human studies. Myeloperoxidase (MPO) is a key mediator of the inflammatory response, via production of specific oxidative species, e.g., the hypohalous acids. Specific tissue modifications, mediated by hypohalous acids, have been documented in multiple cardiovascular pathologies, including atherosclerosis associated with coronary artery disease, abdominal aortic, and cerebral aneurysms. Similarly, data are now emerging that show the capacity of MPO-derived oxidative species to regulate mechanisms important in TAA pathogenesis, including alterations in extracellular matrix homeostasis, activation of matrix metalloproteinases, induction of endothelial dysfunction and vascular smooth muscle cell phenotypic switching, and activation of ERK1/2 signaling. The weight of evidence supports a role for inflammation in exacerbating the severity of TAA progression, expanding our understanding of the pathogenesis of TAA, identifying potential biomarkers for early detection of TAA, monitoring severity and progression, and for defining potential novel therapeutic targets.

Genetically triggered thoracic aortic aneurysms (TAAs) account for 30% of all TAAs and can result in early morbidity and mortality in affected individuals. Epigenetic factors are now recognised to influence the phenotype of many genetically triggered conditions and have become an area of interest because of the potential for therapeutic manipulation. Major epigenetic modulators include DNA methylation, histone modification and non-coding RNA. This review examines epigenetic modulators that have been significantly associated with genetically triggered TAAs and their potential utility for translation to clinical practice.

Bicuspid aortic valve (BAV) is the most common congenital heart malformation, affecting 1-2% of the population. BAV is caused by fusion of two of the three aortic valve leaflets in the heart during foetal development. Progressive dilatation of the thoracic aorta, resulting in aneurysm (TAA), develops in approximately 50% of individuals with BAV, and can be fatal. The cause of BAV-TAA is undetermined, however, current understanding suggests that it is a complex interplay between genetic susceptibility and the abnormal haemodynamic stress generated by the malformed valve. Changes in the expression of post-transcriptional genetic modifiers, such as microRNA (miRNA), can alter protein expression and disrupt normal tissue function, contributing to disease. miRNA are also viable therapeutic targets with demonstrated success in disease treatment. We hypothesised that there is altered expression of miRNA in BAV-TAA tissue that contributes to TAA development. Total RNA was isolated from aortic tissue of 11 patients with BAV-TAA (Age 54 ± 12 years; M:F 10:1), and 6 normal controls with no aortic disease (Age 35 ± 18 years; M:F 4:2). RNA was reverse transcribed with primers for 818 different miRNA and qPCR was performed using Taqman® OpenArray® Human miRNA Panels. A significant difference in miRNA expression was defined as a >±2 fold change (p

Rationale: Thoracic aortic aneurysm (TAA) is a potentially lethal condition, which can affect individuals of all ages. TAA may be complicated by the sudden onset of life-threatening dissection or rupture. The underlying mechanisms leading to TAA formation, particularly in the nonsyndromal idiopathic group of patients, are not well understood. Thus, identification of new genes and targets that are involved in TAA pathogenesis are required to help prevent and reverse the disease phenotype. Objective: Here we explore the role of ARHGAP18, a novel Rho GAP expressed by smooth muscle cells (SMCs), in the pathogenesis of TAA. Methods and Results: Using human and mouse aortic samples, we report that ARHGAP18 levels were significantly reduced in the SMC layer of aortic aneurysms. Arhgap18 global knockout ( Arhgap18 −/ − ) mice exhibited a highly synthetic, proteolytic, and proinflammatory smooth muscle phenotype under basal conditions and when challenged with angiotensin II, developed TAA with increased frequency and severity compared with littermate controls. Chromatin immunoprecipitation studies revealed this phenotype is partly associated with strong enrichment of H3K4me3 and depletion of H3K27me3 at the MMP2 and TNF-α promoters in Arhgap18 -deficient SMC. We further show that TAA formation in the Arhgap18 −/− mice is associated with loss of Akt activation. The abnormal SMC phenotype observed in the Arhgap18 −/− mice can be partially rescued by pharmacological treatment with the mTORC1 inhibitor rapamycin, which reduces the synthetic and proinflammatory phenotype of Arhgap18 -deficient SMC. Conclusion: We have identified ARHGAP18 as a novel protective gene against TAA formation and define an additional target for the future development of treatments to limit TAA pathogenesis.

Thoracic aortic aneurysm and dissection in young and middle aged patients is increasingly recognised as due to genetic aortopathy. Mutations in multiple genes affecting proteins in the extracellular matrix, microfibrillar structure, the endothelium and cell signalling pathways have been associated with thoracic aortic disease. The TGFß signalling pathway appears to play a key role in mediating abnormal aortic growth and aneurysm formation. A challenge remains in understanding how the many different gene mutations can result in deranged TGFß signalling. This review examines the functional relationships between key structural and signalling proteins, with reference to the need for maintenance of homeostasis in mechanotransduction within the aortic wall. A mechanism, through which perturbations in mechanotransduction, arising from different gene mutations, results in altered TGFß signalling is described.

Background Marfan syndrome (MFS) and familial non–syndromal thoracic aortic aneurysm and dissection (ns‐TAAD) are genetic aortopathies causing aortic dilatation with increased aortic stiffness. Left ventricular (LV) contractility and ventricular‐vascular coupling index (VVI) were compared between MFS and ns‐TAAD and determinants of VVI were investigated. Methods and Results Patients with MFS (M 57, F 47) and ns‐TAAD (M 72, F 39) were studied by echocardiography and compared with controls (M 77, F 71). Aortic geometry, hemodynamics, LV work, LV contractility (end‐systolic elastance [E es ]), and VVI were documented. Aortic sinuses were equally dilated in MFS (19.7±2.4) and ns‐TAAD (19.8±1.8) compared to controls (16.2±1.4 mm·m −2 , P P −2 P es was reduced in MFS (1.32±0.19) compared to controls (1.65±0.29 mm Hg·mL −1 , P P P Conclusions Left ventricular contractility and ventricular‐vascular coupling are abnormal in MFS but preserved in ns‐TAAD, and are independent of aortic stiffness, consistent with intrinsic impairment of myocardial contractility in MFS.

Thoracic aortic aneurysms in Marfan Syndrome (MFS) caused by mutations in FBN1 are associated with altered TGF-β signaling. Regulation of gene expression can occur at the level of microRNA, which can modify signaling pathways. We hypothesized that there would be altered microRNA expression in MFS that may alter the expression of signaling proteins. Total RNA was isolated from whole blood collected in PAXgene® tubes (PreAnalytiX), from 13 MFS patients with aortic dilatation (6F, 7M; Ao Diameter 44.4±6.0mm; Age 39±12yrs) and 10 normal controls (5F, 5M; Ao Diameter 32.3±5mm; Age 34±10yrs). The RNA was reverse transcribed with Human Pool A & B primers and qPCR was performed on the subsequent cDNA using TaqMan® OpenArray® Human miRNA Panels (2454 targets) (ThermoFisher). microRNA expression was considered to be significantly altered if there was >2 fold change (p In MFS patients, the OpenArray® identified 30 microRNA were significantly altered (22 up regulated, 8 down regulated). Of these, 12 were confirmed to be altered using targeted qPCR (Graph 1). Three of these have previously been identified as modifiers of the TGF-β signaling pathway (miR 17, miR 93, miR 93*). Three were from the let-7 family (let-7e, let-7f, let-7g), which are involved in terminal cell differentiation and have been implicated in several cardiovascular disease processes. Another three have been shown to be dysregulated in various cardiovascular disease states including atherosclerotic thoracic aortic aneurysm and left ventricular hypertrophy (miR 208, miR 486, miR 378). This study provides novel evidence for adaptive responses at the post-transcriptional level of gene expression that may modulate aneurysm development in Marfan syndrome.

Multiple genes are associated with thoracic aortic aneurysm (TAA) formation, including FBN1, TGFBR1&2, COL3A1 & 5A2, and MYH11. We hypothesized that given the population incidence of mutations in these genes it is likely that ‘double-hit’ mutations occur, which may result in an altered clinical phenotype when compared with the single gene mutation.Genomic DNA analysis of 16 genes implicated in TAA was performed on 11 patients with inherited TAA disease. Of the patients analysed, one patient (P1) was identified as having a mutation in both MYH11 (c.2517G.C (pW839C)) and FBN1 (splice donor site c.4210+1G>A). Another patient (P2) was identified as having both COL5A2 (c.3794A>G (pD1265G)) and FBN1 (c.5861T>G (p.F1954C)). All mutations were predicted by PolyPhen to be deleterious.P1 has Marfan Syndrome (MFS), caused by the FBN1 mutation, and has severe aortic dilatation while his mother (M1), who also has MFS but does not have the MHY11 mutation, developed mild aortic dilatation, suggesting that the MHY11 mutation in P1 has resulted in a more aggressive phenotype.P2, siblings S1 and S2 and father (F2) all have relatively less severe MFS with progressive moderate dilatation of the aorta. Thus, the phenotype of pedigree 2 is similar for all affected members, but only P2 has a double-hit mutation, suggesting that the presence of the COL5A2 mutation in P2 has not altered the clinical phenotype.The potential contribution of these mutations to phenotype using molecular modelling will be presented. This is the first instance where double-hit mutations have been described in familial TAA but the effect of multiple mutations on phenotype appears to be variable. Mutation analysis for individuals with familial TAA should look beyond the identification of a single gene culprit.

Upregulated TGFβ signalling plays a key role in mediating congenital thoracic aortic aneurysms (TAA), and has been implicated in bicuspid aortic valve-associated TAA (BAV-TAA). TGFβ is normally stored within the extra-cellular matrix via sequestration proteins bound to the microfibrillar protein, fibrillin. TGFβ is released in response to changes in these sequestration proteins, allowing TGFβ to exert its signalling effects. We hypothesised that in BAV-TAA the upregulation of TGFβ signalling will pathologically alter effector molecule expression, causing matrix degradation and altered TGFβ sequestration. Immunohistochemistry was used to quantify protein expression in aortic tissue from 8 human BAV-TAA and 6 normal controls. In BAV-TAA, TGFβ expression was elevated in all layers (2.5:1; p