Contribution of Extra-Cardiac Cells in Murine Heart Valves is Age-Dependent

Multiscale structure and function of the aortic valve apparatus

Whereas studying the aortic valve in isolation has facilitated the development of life-saving procedures and technologies, the dynamic interplay of the aortic valve and its surrounding structures is vital to preserving their function across the wide range of conditions encountered in an active lifestyle. Our view is that these structures should be viewed as an integrated functional unit, here referred to as the aortic valve apparatus (AVA). The coupling of the aortic valve and root, left ventricular outflow tract, and blood circulation is crucial for AVA's functions: unidirectional flow out of the left ventricle, coronary perfusion, reservoir function, and support of left ventricular function. In this review, we explore the multiscale biological and physical phenomena that underlie the simultaneous fulfillment of these functions. A brief overview of the tools used to investigate the AVA, such as medical imaging modalities, experimental methods, and computational modeling, specifically fluid-structure interaction (FSI) simulations, is included. Some pathologies affecting the AVA are explored, and insights are provided on treatments and interventions that aim to maintain quality of life. The concepts explained in this article support the idea of AVA being an integrated functional unit and help identify unanswered research questions. Incorporating phenomena through the molecular, micro, meso, and whole tissue scales is crucial for understanding the sophisticated normal functions and diseases of the AVA.

Single-cell and Spatial Transcriptomics Identified Fatty Acid-binding Proteins Controlling Endothelial Glycolytic and Arterial Programming in Pulmonary Hypertension

Pulmonary arterial hypertension (PAH) is a devastating disease characterized by obliterative vascular remodeling and persistent increase of vascular resistance, leading to right heart failure and premature death. Understanding the cellular and molecular mechanisms will help develop novel therapeutic approaches for PAH patients. Single-cell RNA sequencing (scRNAseq) analysis found that both FABP4 and FABP5 were highly induced in endothelial cells (ECs) of Egln1Tie2Cre (CKO) mice, which was also observed in pulmonary arterial ECs (PAECs) from idiopathic PAH (IPAH) patients, and in whole lungs of pulmonary hypertension (PH) rats. Plasma levels of FABP4/5 were upregulated in IPAH patients and directly correlated with severity of hemodynamics and biochemical parameters using plasma proteome analysis. Genetic deletion of both Fabp4 and 5 in CKO mice (Egln1Tie2Cre/Fabp4-5-/- ,TKO) caused a reduction of right ventricular systolic pressure (RVSP) and RV hypertrophy, attenuated pulmonary vascular remodeling and prevented the right heart failure assessed by echocardiography, hemodynamic and histological analysis. Employing bulk RNA-seq and scRNA-seq, and spatial transcriptomic analysis, we showed that Fabp4/5 deletion also inhibited EC glycolysis and distal arterial programming, reduced ROS and HIF-2α expression in PH lungs. Thus, PH causes aberrant expression of FABP4/5 in pulmonary ECs which leads to enhanced ECs glycolysis and distal arterial programming, contributing to the accumulation of arterial ECs and vascular remodeling and exacerbating the disease.

Developing Cardiac Digital Twins at Scale: Insights from Personalised Myocardial Conduction Velocity

Large-cohort studies using cardiovascular imaging and diagnostic datasets have assessed cardiac anatomy, function, and outcomes, but typically do not reveal underlying biological mechanisms. Cardiac digital twins (CDTs) provide personalized physics- and physiology-constrained in-silico representations, enabling inference of multi-scale properties tied to these mechanisms. We constructed 3464 anatomically-accurate CDTs using cardiac magnetic resonance images from UK biobank and personalised their myocardial conduction velocities (CVs) from electrocardiograms (ECG), through an automated framework. We found well-known sex-specific differences in QRS duration were fully explained by myocardial anatomy, as CV remained consistent across sexes. Conversely, significant associations of CV with ageing and increased BMI suggest myocardial tissue remodelling. Novel associations were observed with left ventricular ejection fraction and mental-health phenotypes, through a phenome-wide association study, and CV was also linked with adverse clinical outcomes. Our study highlights the utility of population-based CDTs in assessing intersubject variability and uncovering strong links with mental health.

Role of community-based health clubs in promoting patients' health education for diabetes self-care management: an interventional qualitative study in a Ugandan urban setting

BACKGROUND

Self-care management support is a core component of the Chronic Care Model that emphasises the need for empowering and preparing patients to manage their healthcare. In diabetes mellitus (DM) management, health education towards self-care empowers patients to make day-to-day decisions on their own disease and live with a healthy lifestyle. Although several strategies have been undertaken to improve the management of DM in Uganda, little has been done to empower patients to manage their own health. Community-based health clubs have been suggested as a novel way of improving diabetes management especially in settings with uneven distribution of healthcare facilities and inaccessibility to healthcare services that limit patients' awareness of the disease and self-care management. This interventional study was aimed at exploring the role of community-based health clubs in promoting patients' health education for diabetes self-care management.

METHODS

A cross-sectional qualitative study was conducted among 20 participants using focus group discussions with each having six to eight members. Only patients with diabetes who seek routine diabetes healthcare services at Wakiso Health Centre IV and had participated in the 8-week community-based health clubs' health education sessions were recruited for the study. The audio-recordings were transcribed verbatim and translated into English; thematic data analysis was conducted to generate codes and themes. Similar codes were merged and a group consensus was reached on coding discrepancies.

RESULTS

Three major themes on the role of health clubs in promoting patients' health education were merged from the study. These include promoting sharing of experiences among patients, improving awareness of healthy self-care practices and offering sufficient patient-health worker interaction time.

CONCLUSIONS

This is the first publication reporting on the role of community-based health clubs in promoting patients' health education towards diabetes self-care management in Uganda. The ability to share experiences among patients, improve patients' awareness on healthy living practices and the increased health worker-patient interaction time contribute heavily to the capacity-building for self-care among patients.

Acute kidney injury after endovascular therapy in acute stroke patients: systematic review with meta-analysis

AIMS

Endovascular therapy (EVT) is a highly effective stroke treatment, but it requires the administration of contrast media which puts patients at risk of acute kidney injury (AKI). AKI is associated with increased morbidity and mortality in cardiovascular patients.

METHODS

PubMed, Scopus, ISI and the Cochrane Library were systematically searched for observational and experimental studies assessing the occurrence of AKI in adult acute stroke patients submitted to EVT. Two independent reviewers collected study data regarding study setting, period, source of data, and AKI definition and predictors, the outcomes of interest being AKI incidence and 90-day death or dependency (modified Rankin Scale score ≥3). These outcomes were pooled using random effect models, and heterogeneity was measured using the I2 statistic.

RESULTS

22 studies were identified and included in the analysis, involving 32 034 patients. Pooled incidence of AKI was 7% (95% CI 5% to 10%), but heterogeneity was high across studies (I2=98%), and not accounted for by the definition of AKI used. The most frequently reported AKI predictors were impaired baseline renal function (5 studies) and diabetes (3 studies); 3 studies (2103 patients) reported data on death and 4 studies (2424 patients) reported data on dependency. Overall, AKI was associated with both outcomes, with ORs of 6.21 (95% CI 3.52 to 10.96) and 2.86 (95% CI 1.88 to 4.37), respectively. Heterogeneity was low for both analyses (I2=0%).

CONCLUSIONS

AKI affects 7% of acute stroke patients submitted to EVT and identifies a subgroup of patients for which treatment outcomes are suboptimal, with an increased risk of death and dependency.

Disparities in Huntington Disease Severity: Analysis Using the ENROLL-HD Dataset

Background and Objectives

Social and structural determinants of health (SDOH) have been associated with disability in neurologic diseases. However, the association between these factors and disability in Huntington disease (HD) has not been studied. This study aimed to evaluate the association of racial and sociodemographic factors with disease severity in patients with HD in North America.

Methods

We conducted a cross-sectional study of genetically confirmed participants with HD (36+ CAG repeats) in the North American region using the ENROLL-HD 2020 periodic dataset. In this analysis, our exposure variable was the participant's race/ethnicity. The main outcome measure was disease severity, as measured by the Total Functional Capacity Score (TFC), which measures the level of disability of patients with HD. We used multivariate regression models to adjust for sociodemographic factors that may mediate or moderate a causal effect between race/ethnicity and disease severity.

Results

Among 4,717 gene-positive participants in the North American region, 89.5% identified as White, 3.4% as Hispanic or Latino, and 2.3% as African American/Black. The average TFC score was 10.22 (SD 3.22); 48% of participants completed either secondary education (including college) or a professional degree, and 55% lived in a city and not in a town, village, or rural location. In multivariate regression models, we found that Black participants and those with less than a high school degree entered the ENROLL-HD study with lower TFC scores than White participants. We also found that compared with those with at least a high school degree, those who completed some form of higher education or professional degree had higher TFC scores (p < 0.001). This multivariate analysis did not find an association between geographic location and TFC score.

Discussion

Our study found that Black participants in North America presented to ENROLL-HD with more advanced disease than White patients. We also found that higher education was associated with less advanced disease when entering the ENROLL-HD study. The role of race/ethnicity and education in HD symptom severity warrants further investigation. These findings underscore the importance of further studying the role of social and structural determinants of health in patients with HD, particularly those from historically marginalized communities.

Functional regeneration at the blood-biomaterial interface

The use of cardiovascular implants is commonplace in clinical practice. However, reproducing the key bioactive and adaptive properties of native cardiovascular tissues with an artificial replacement is highly challenging. Exciting new treatment strategies are under development to regenerate (parts of) cardiovascular tissues directly in situ using immunomodulatory biomaterials. Direct exposure to the bloodstream and hemodynamic loads is a particular challenge, given the risk of thrombosis and adverse remodeling that it brings. However, the blood is also a source of (immune) cells and proteins that dominantly contribute to functional tissue regeneration. This review explores the potential of the blood as a source for the complete or partial in situ regeneration of cardiovascular tissues, with a particular focus on the endothelium, being the natural blood-tissue barrier. We pinpoint the current scientific challenges to enable rational engineering and testing of blood-contacting implants to leverage the regenerative potential of the blood.

WGCNA and molecular docking identify hub genes for cardiac aging

Background

Cardiac aging and ageing-related cardiovascular diseases remain increase medical and social burden. Discovering the molecular mechanisms associated with cardiac aging is expected to provide new perspectives for delaying aging and related disease treatment.

Methods

The samples in GEO database were divided into older group and younger group based on age. Age-associated differentially expressed genes (DEGs) were identified by limma package. Gene modules significantly associated with age were mined using weighted gene co-expression network analysis (WGCNA). Protein-protein interaction networks (PPI) networks were developed using genes within modules, and topological analysis on the networks was performed to identify hub genes in cardiac aging. Pearson correlation was used to analyze the association among hub genes and immune and immune-related pathways. Molecular docking of hub genes and the anti-aging drug Sirolimus was performed to explore the potential role of hub genes in treating cardiac aging.

Results

We found a generally negative correlation between age and immunity, with a significant negative correlation between age and b_cell_receptor_signaling_pathway, fc_gamma_r_mediated_phagocytosis, chemokine signaling pathway, t-cell receptor signaling pathway, toll_like_receptor_signaling_pathway, and jak_stat_signaling_pathway, respectively. Finally, 10 cardiac aging-related hub genes including LCP2, PTPRC, RAC2, CD48, CD68, CCR2, CCL2, IL10, CCL5 and IGF1 were identified. 10-hub genes were closely associated with age and immune-related pathways. There was a strong binding interaction between Sirolimus-CCR2. CCR2 may be a key target for Sirolimus in the treatment of cardiac aging.

Conclusion

The 10 hub genes may be potential therapeutic targets for cardiac aging, and our study provided new ideas for the treatment of cardiac aging.

Macrophage-extracellular matrix interactions: Perspectives for tissue engineered heart valve remodeling

In situ heart valve tissue engineering approaches have been proposed as promising strategies to overcome the limitations of current heart valve replacements. Tissue engineered heart valves (TEHVs) generated from in vitro grown tissue engineered matrices (TEMs) aim at mimicking the microenvironmental cues from the extracellular matrix (ECM) to favor integration and remodeling of the implant. A key role of the ECM is to provide mechanical support to and attract host cells into the construct. Additionally, each ECM component plays a critical role in regulating cell adhesion, growth, migration, and differentiation potential. Importantly, the immune response to the implanted TEHV is also modulated biophysically via macrophage-ECM protein interactions. Therefore, the aim of this review is to summarize what is currently known about the interactions and signaling networks occurring between ECM proteins and macrophages, and how these interactions may impact the long-term in situ remodeling outcomes of TEMs. First, we provide an overview of in situ tissue engineering approaches and their clinical relevance, followed by a discussion on the fundamentals of the remodeling cascades. We then focus on the role of circulation-derived and resident tissue macrophages, with particular emphasis on the ramifications that ECM proteins and peptides may have in regulating the host immune response. Finally, the relevance of these findings for heart valve tissue engineering applications is discussed.

Human cytomegalovirus infection is associated with stroke in women: the US National Health and Nutrition Examination Survey 1999-2004

BACKGROUND

Increasing evidence indicated that infection factors play important roles in stroke development. Human cytomegalovirus (HCMV) infection was positively associated with atherosclerosis and hypertension which are stroke risk factors. Therefore, we aimed to explore the relationship between HCMV infection and stroke using the data of US National Health and Nutrition Examination Survey (NHANES).

METHODS

We analysed data on 2844 men and 3257 women in the NHANES 1999-2004. We included participants aged 20-49 years who had valid data on HCMV infection and stroke.

RESULTS

54.1% of participants had serological evidence of HCMV infection and 0.8% of them had a previous diagnosis of stroke. There were ethnic differences in the prevalence of HCMV seropositivity (p<0.001). There was no significant association between HCMV seropositivity and stroke in men in any of the models. In women, HCMV seropositivity was associated with stroke before adjustment (OR=3.45, 95% CI 1.09 to 10.95, p=0.036). After adjusting for race/ethnicity, the association remained significant (OR=4.40, 95% CI 1.37 to 14.09, p=0.014). After further adjustment for body mass index, diabetes, hypercholesterolaemia, hypertension, alcohol consumption, smoking and physical activity, the association still existed (OR=3.58, 95% CI 1.14 to 11.25, p=0.030). The association was significant consistently in adjusted model for age (OR=3.39, 95% CI 1.08 to 10.64, p=0.037).

CONCLUSIONS

We found a strong association between HCMV and stroke in women from the nationally representative population-based survey. This provide additional motivation for undertaking the difficult challenge to reduce the prevalence of stroke.

Myeloid leukocytes' diverse effects on cardiovascular and systemic inflammation in chronic kidney disease

Chronic kidney disease's prevalence rises globally. Whereas dialysis treatment replaces the kidney's filtering function and prolongs life, dreaded consequences in remote organs develop inevitably over time. Even milder reductions in kidney function not requiring replacement therapy associate with bacterial infections, cardiovascular and heart valve disease, which markedly limit prognosis in these patients. The array of complications is diverse and engages a wide gamut of cellular and molecular mechanisms. The innate immune system is profoundly and systemically altered in chronic kidney disease and, as a unifying element, partakes in many of the disease's complications. As such, a derailed immune system fuels cardiovascular disease progression but also elevates the propensity for serious bacterial infections. Recent data further point towards a role in developing calcific aortic valve stenosis. Here, we delineate the current state of knowledge on how chronic kidney disease affects innate immunity in cardiovascular organs and on a systemic level. We review the role of circulating myeloid cells, monocytes and neutrophils, resident macrophages, dendritic cells, ligands, and cellular pathways that are activated or suppressed when renal function is chronically impaired. Finally, we discuss myeloid cells' varying responses to uremia from a systems immunology perspective.

Bystander interventions and survival after exercise-related sudden cardiac arrest: a systematic review

OBJECTIVE

To evaluate the provision of bystander interventions and rates of survival after exercise-related sudden cardiac arrest (SCA).

DESIGN

Systematic review.

DATA SOURCES

MEDLINE, EMBASE, PubMed, CINAHL, SPORTDiscus, Cochrane Library and grey literature sources were searched from inception to November/December 2020.

STUDY ELIGIBILITY CRITERIA

Observational studies assessing a population of exercise-related SCA (out-of-hospital cardiac arrests that occurred during exercise or within 1 hour of cessation of activity), where bystander cardiopulmonary resuscitation (CPR) and/or automated external defibrillator (AED) use were reported, and survival outcomes were ascertained.

METHODS

Among all included studies, the median (IQR) proportions of bystander CPR and bystander AED use, as well as median (IQR) rate of survival to hospital discharge, were calculated.

RESULTS

A total of 29 studies were included in this review, with a median study duration of 78.7 months and a median sample size of 91. Most exercise-related SCA patients were male (median: 92%, IQR: 86%-96%), middle-aged (median: 51, IQR: 39-56 years), and presented with a shockable arrest rhythm (median: 78%, IQR: 62%-86%). Bystander CPR was initiated in a median of 71% (IQR: 59%-87%) of arrests, whereas bystander AED use occurred in a median of 31% (IQR: 19%-42%) of arrests. Among the 19 studies that reported survival to hospital discharge, the median rate of survival was 32% (IQR: 24%-49%). Studies which evaluated the relationship between bystander interventions and survival outcomes reported that both bystander CPR and AED use were associated with survival after exercise-related SCA.

CONCLUSION

Exercise-related SCA occurs predominantly in males and presents with a shockable ventricular arrhythmia in most cases, emphasising the importance of rapid access to defibrillation. Further efforts are needed to promote early recognition and a rapid bystander response to exercise-related SCA.

Tgfβ1-Cthrc1 Signaling Plays an Important Role in the Short-Term Reparative Response to Heart Valve Endothelial Injury

OBJECTIVE

Aortic valve disease is a common worldwide health burden with limited treatment options. Studies have shown that the valve endothelium is critical for structure-function relationships, and disease is associated with its dysfunction, damage, or injury. Therefore, therapeutic targets to maintain a healthy endothelium or repair damaged endothelial cells could hold promise. In this current study, we utilize a surgical mouse model of heart valve endothelial cell injury to study the short-term response at molecular and cellular levels. The goal is to determine if the native heart valve exhibits a reparative response to injury and identify the mechanisms underlying this process. Approach and Results: Mild aortic valve endothelial injury and abrogated function was evoked by inserting a guidewire down the carotid artery of young (3 months) and aging (16-18 months) wild-type mice. Short-term cellular responses were examined at 6 hours, 48 hours, and 4 weeks following injury, whereas molecular profiles were determined after 48 hours by RNA-sequencing. Within 48 hours following endothelial injury, young wild-type mice restore endothelial barrier function in association with increased cell proliferation, and upregulation of transforming growth factor beta 1 (Tgfβ1) and the glycoprotein, collagen triple helix repeat containing 1 (Cthrc1). Interestingly, this beneficial response to injury was not observed in aging mice with known underlying endothelial dysfunction.

CONCLUSIONS

Data from this study suggests that the healthy valve has the capacity to respond to mild endothelial injury, which in short term has beneficial effects on restoring endothelial barrier function through acute activation of the Tgfβ1-Cthrc1 signaling axis and cell proliferation.

Outcomes in patients with a first episode of chest pain undergoing early coronary CT imaging

Objectives

To investigate the impact of a CT-first strategy on all-cause and cardiovascular mortality in patients presenting with chest pain in outpatient cardiology clinics.

Methods

Patients with a first presentation of suspected angina pectoris were identified and their data linked to the registrations of Statistics Netherlands for information on mortality. The linked database consisted of 33 068 patients. CT-first patients were defined as patients with a CT calcium score and coronary CT angiography, within 6 weeks after their initial visit. Propensity score matching (1:5) was used to match patients with and without a CT-first strategy. After matching, 12 545 patients were included of which 2308 CT-first patients and 10 237 patients that underwent usual care.

Results

Mean age was 57 years, 56.3% were women and median follow-up was 4.9 years. All-cause mortality was significantly lower in CT-first patients (n=43, 1.9%) compared with patients without CT (n=363, 3.5%) (HR: 0.51, 95% CI 0.37 to 0.70). Furthermore, CT-first patients were more likely to receive cardiovascular preventative and antianginal medication (aspirin: 44.9% vs 27.1%, statins: 48.7% vs 30.3%, beta-blockers: 37.8% vs 25.5%, in CT-first and without CT-first patients, respectively) and to undergo downstream diagnostics and interventions (coronary interventions: 8.5% vs 5.7%, coronary angiography: 16.2% vs 10.6% in CT-first and without CT-first patients, respectively).

Conclusions

In a real-world regular care database, a CT-first strategy in patients suspected of angina pectoris was associated with a lowering of all-cause mortality.

Immuno-regenerative biomaterials for in situ cardiovascular tissue engineering - Do patient characteristics warrant precision engineering?

In situ tissue engineering using bioresorbable material implants - or scaffolds - that harness the patient's immune response while guiding neotissue formation at the site of implantation is emerging as a novel therapy to regenerate human tissues. For the cardiovascular system, the use of such implants, like blood vessels and heart valves, is gradually entering the stage of clinical translation. This opens up the question if and to what extent patient characteristics influence tissue outcomes, necessitating the precision engineering of scaffolds to guide patient-specific neo-tissue formation. Because of the current scarcity of human in vivo data, herein we review and evaluate in vitro and preclinical investigations to predict the potential role of patient-specific parameters like sex, age, ethnicity, hemodynamics, and a multifactorial disease profile, with special emphasis on their contribution to the inflammation-driven processes of in situ tissue engineering. We conclude that patient-specific conditions have a strong impact on key aspects of in situ cardiovascular tissue engineering, including inflammation, hemodynamic conditions, scaffold resorption, and tissue remodeling capacity, suggesting that a tailored approach may be required to engineer immuno-regenerative biomaterials for safe and predictive clinical applicability.

Surgical aortic valve replacement in the era of transcatheter aortic valve implantation: a review of the UK national database

OBJECTIVES

To date the reported outcomes of surgical aortic valve replacement (SAVR) are mainly in the settings of trials comparing it with evolving transcatheter aortic valve implantation. We set out to examine characteristics and outcomes in people who underwent SAVR reflecting a national cohort and therefore 'real-world' practice.

DESIGN

Retrospective analysis of prospectively collected data of consecutive people who underwent SAVR with or without coronary artery bypass graft (CABG) surgery between April 2013 and March 2018 in the UK. This included elective, urgent and emergency operations. Participants' demographics, preoperative risk factors, operative data, in-hospital mortality, postoperative complications and effect of the addition of CABG to SAVR were analysed.

SETTING

27 (90%) tertiary cardiac surgical centres in the UK submitted their data for analysis.

PARTICIPANTS

31 277 people with AVR were identified. 19 670 (62.9%) had only SAVR and 11 607 (37.1%) had AVR+CABG.

RESULTS

In-hospital mortality for isolated SAVR was 1.9% (95% CI 1.6% to 2.1%) and was 2.4% for AVR+CABG. Mortality by age category for SAVR only were: <60 years=2.0%, 60-75 years=1.5%, >75 years=2.2%. For SAVR+CABG these were; 2.2%, 1.8% and 3.1%. For different categories of EuroSCORE, mortality for SAVR in low risk people was 1.3%, in intermediate risk 1% and for high risk 3.9%. 74.3% of the operations were elective, 24% urgent and 1.7% emergency/salvage. The incidences of resternotomy for bleeding and stroke were 3.9% and 1.1%, respectively. Multivariable analyses provided no evidence that concomitant CABG influenced outcome. However, urgency of the operation, poor ventricular function, higher EuroSCORE and longer cross clamp and cardiopulmonary bypass times adversely affected outcomes.

CONCLUSIONS

Surgical SAVR±CABG has low mortality risk and a low level of complications in the UK in people of all ages and risk factors. These results should inform consideration of treatment options in people with aortic valve disease.

Inflammaging as a link between autoimmunity and cardiovascular disease: the case of rheumatoid arthritis

Currently, traditional and non-traditional risk factors for cardiovascular disease have been established. The first group includes age, which constitutes one of the most important factors in the development of chronic diseases. The second group includes inflammation, the pathophysiology of which contributes to an accelerated process of vascular remodelling and atherogenesis in autoimmune diseases. Indeed, the term inflammaging has been used to refer to the inflammatory origin of ageing, explicitly due to the chronic inflammatory process associated with age (in healthy individuals). Taking this into account, it can be inferred that people with autoimmune diseases are likely to have an early acceleration of vascular ageing (vascular stiffness) as evidenced in the alteration of non-invasive cardiovascular tests such as pulse wave velocity. Thus, an association is created between autoimmunity and high morbidity and mortality rates caused by cardiovascular disease in this population group. The beneficial impact of the treatments for rheumatoid arthritis at the cardiovascular level has been reported, opening new opportunities for pharmacotherapy.

Inflammatory and Biomechanical Drivers of Endothelial-Interstitial Interactions in Calcific Aortic Valve Disease

Calcific aortic valve disease is dramatically increasing in global burden, yet no therapy exists outside of prosthetic replacement. The increasing proportion of younger and more active patients mandates alternative therapies. Studies suggest a window of opportunity for biologically based diagnostics and therapeutics to alleviate or delay calcific aortic valve disease progression. Advancement, however, has been hampered by limited understanding of the complex mechanisms driving calcific aortic valve disease initiation and progression towards clinically relevant interventions.

Association among age, gender, menopausal status and small dense low-density lipoprotein cholesterol: a cross-sectional study

OBJECTIVES

Small dense low-density lipoprotein cholesterol (sdLDL-C) might be a better cardiovascular disease (CVD) indicator than low-density lipoprotein cholesterol (LDL-C); however, details regarding its epidemiology remain elusive. The present study aimed at evaluating the association between the demographic factors, such as age, gender and menopausal status, and sdLDL-C levels and sdLDL-C/LDL-C ratio in the Japanese population.

DESIGN

This was a cross-sectional study.

SETTING

13 rural districts in Japan, 2010-2017.

PARTICIPANTS

This study included 5208 participants (2397 men and 2811 women), who underwent the health mass screening that was conducted in accordance with the medical care system for the elderly and obtained informed consent for this study.

RESULTS

In total, 517 premenopausal women (mean age ±SD, 45.1±4.2 years), 2294 postmenopausal women (66.5±8.8 years) and 2397 men (64.1±11.2 years) were analysed. In men, the sdLDL-C levels and sdLDL-C/LDL-C ratio increased during younger adulthood, peaked (36.4 mg/dL, 0.35) at 50-54 years, and then decreased. In women, relatively regular increasing trends of sdLDL-C level and sdLDL-C/LDL-C ratio until approximately 65 years (32.7 mg/dL, 0.28), followed by a downward or pleated trend. Given the beta value of age, body mass index, fasting glucose and smoking and drinking status by multiple linear regression analysis, standardised sdLDL-C levels and sdLDL-C/LDL-C ratio in 50-year-old men, premenopausal women and postmenopausal women were 26.6, 22.7 and 27.4 mg/dL and 0.24, 0.15 and 0.23, respectively. The differences between premenopausal and postmenopausal women were significant (p<0.001).

CONCLUSIONS

SdLDL-C and sdLDL-C/LDL-C ratios showed different distributions by age, gender and menopausal status. A subgroup-specific approach would be necessary to implement sdLDL-C for CVD prevention strategies, fully considering age-related trends, gender differences and menopausal status.

The Endocardium and Heart Valves

Endocardial cells are specialized endothelial cells that, during embryogenesis, form a lining on the inside of the developing heart, which is maintained throughout life. Endocardial cells are an essential source for several lineages of the cardiovascular system including coronary endothelium, endocardial cushion mesenchyme, cardiomyocytes, mural cells, fibroblasts, liver vasculature, adipocytes, and hematopoietic cells. Alterations in the differentiation programs that give rise to these lineages has detrimental effects, including premature lethality or significant structural malformations present at birth. Here, we will review the literature pertaining to the contribution of endocardial cells to valvular, and nonvalvular lineages and highlight critical pathways required for these processes. The lineage differentiation potential of embryonic, and possibly adult, endocardial cells has therapeutic potential in the regeneration of damaged cardiac tissue or treatment of cardiovascular diseases.

Strategies for enhancing the initiation of cholesterol lowering medication among patients at high cardiovascular disease risk: a qualitative descriptive exploration of patient and general practitioners' perspectives on a facilitated relay intervention in Alberta, Canada

OBJECTIVE

The objective of our study was to explore the perspectives of patients and general practitioners (GPs) regarding interventions to increase initiation of cholesterol lowering medication (or statins), including a proposed laboratory-based facilitated relay intervention.

DESIGN

Qualitative descriptive study using interviews and focus groups for data collection, and thematic analysis for data analysis.

SETTING

Primary care providers and patients in Calgary, Alberta, Canada.

PARTICIPANTS

17 GPs with primarily community-based, non-academic practices with at least 1 year of practice experience participated in semistructured interviews. 14 patients at high risk of cardiovascular disease participated in focus groups.

MAIN OUTCOME MEASURES

Exploration of strategies that might be used to enhance the prescription of, and adherence to statin therapy for patients with statin-indicated conditions.

RESULTS

GPs proposed a variety of interventions to improve statin prescription, including electronic record audit solutions, GP directed education, and patient-oriented campaigns. Patients expressed that they may benefit from being provided access to their laboratory test results, as well as targeted education. Both parties provided positive feedback on the proposed laboratory-based facilitated relay intervention, while pointing out areas for improvement. Notably, GPs were concerned that the patient-directed component of the intervention might jeopardise therapeutic relationships, and patients were concerned about accidental disclosure of personal health information. Important considerations for the design of facilitated relay messaging should include brevity, simplicity and the provision of contact information for inquiries.

CONCLUSIONS

GPs and patients described several suggestions for increasing statin initiation and welcomed the proposal of a laboratory-based facilitated relay strategy. These findings support further testing of this intervention which may enhance GPs' ability to successfully engage patients in cardiovascular risk reduction through statin therapy.

Epilepsy risk among survivors of intensive care unit hospitalization for sepsis

OBJECTIVE

To determine whether survivors of intensive care unit (ICU) hospitalizations with sepsis experience higher epilepsy risk than survivors of ICU hospitalizations without sepsis, and to identify sepsis survivors at highest risk.

METHODS

We used linked, administrative health care databases to conduct a population-based, retrospective matched cohort study of adult Ontario residents discharged from an ICU between January 1, 2010, and December 31, 2015, identified using the Discharge Abstract Database. We used propensity scores to match patients who experienced sepsis during their index ICU hospitalization with up to 4 patients who did not experience sepsis. We applied marginal Cox proportional hazards regression to estimate the risk of epilepsy within 2 years following the index ICU hospitalization. Among sepsis survivors, Cox proportional hazards regression was used to identify factors associated with epilepsy.

RESULTS

A total of 143,892 patients were included, 32,252 (22.4%) of whom were exposed. Sepsis survivors were at significantly higher epilepsy risk (hazard ratio [HR] 1.44, 95% confidence interval [CI] 1.15-1.80). The risk of epilepsy marginally decreased with increasing age (HR 0.97, 95% CI 0.96-0.99); patients with chronic kidney disease (HR 2.25, 95% CI 1.48-3.43) were at highest risk.

CONCLUSIONS

In this real-world analysis, sepsis survivors, particularly those who are younger and have chronic kidney disease, are at significantly higher epilepsy risk. These findings indicate that sepsis may be an unrecognized epilepsy risk factor.

Troponin T but not C reactive protein is associated with future surgery for aortic stenosis: a population-based nested case-referent study

AIMS

High-sensitivity troponin T (hs-TnT) and high-sensitivity C reactive protein (hs-CRP) may convey prognostic information in patients with aortic stenosis (AS). This study evaluated if hs-TnT and hs-CRP associate with myocardial mass, and risk of future surgery for AS.

METHODS

In total, 336 patients (48% women) with surgery for AS with previous participation in large population surveys were identified. Preoperatively, myocardial mass and the presence of coronary artery disease (CAD) were assessed. Two matched referents were allocated for each case, and hs-TnT and hs-CRP were determined in stored plasma from the baseline survey. Conditional logistic regression analysis was used to estimate the risk (OR (95% CI)) related to one (natural logarithm) SD increase in hs-TnT and hs-CRP. Kaplan-Mayer and Cox regression analyses were used to evaluate time to surgery.

RESULTS

Median age (IQR) was 59.8 (10.3) years at survey, and median time between survey and surgery was 10.9 (9.3) years. Hs-TnT was independently associated with surgery for AS (1.24 (1.06-1.44)) irrespective of CAD, whereas Hs-CRP was not (1.05 (0.90-1.22)). Elevated hs-TnT levels at survey associated with shorter time to surgery (p<0.001), and with increased myocardial mass (p=0.002). Hs-CRP did not associate with time to surgery or with myocardial mass.

CONCLUSIONS

Hs-TnT-but not hs-CRP-was associated with increased risk of-and shorter time to-future surgery for AS. Hs-TnT associated with myocardial mass at surgery which indicates that hs-TnT could be a potential biomarker for determining intervention.

New Concepts in the Development and Malformation of the Arterial Valves

Although in many ways the arterial and atrioventricular valves are similar, both being derived for the most part from endocardial cushions, we now know that the arterial valves and their surrounding structures are uniquely dependent on progenitors from both the second heart field (SHF) and neural crest cells (NCC). Here, we will review aspects of arterial valve development, highlighting how our appreciation of NCC and the discovery of the SHF have altered our developmental models. We will highlight areas of research that have been particularly instructive for understanding how the leaflets form and remodel, as well as those with limited or conflicting results. With this background, we will explore how this developmental knowledge can help us to understand human valve malformations, particularly those of the bicuspid aortic valve (BAV). Controversies and the current state of valve genomics will be indicated.

Secreted Factors From Proinflammatory Macrophages Promote an Osteoblast-Like Phenotype in Valvular Interstitial Cells

OBJECTIVE

Resident valvular interstitial cells (VICs) activate to myofibroblasts during aortic valve stenosis progression, which further promotes fibrosis or even differentiate into osteoblast-like cells that can lead to calcification of valve tissue. Inflammation is a hallmark of aortic valve stenosis, so we aimed to determine proinflammatory cytokines secreted from M1 macrophages that give rise to a transient VIC phenotype that leads to calcification of valve tissue. Approach and Results: We designed hydrogel biomaterials as valve extracellular matrix mimics enabling the culture of VICs in either their quiescent fibroblast or activated myofibroblast phenotype in response to the local matrix stiffness. When VIC fibroblasts and myofibroblasts were treated with conditioned media from THP-1-derived M1 macrophages, we observed robust reduction of αSMA (alpha smooth muscle actin) expression, reduced stress fiber formation, and increased proliferation, suggesting a potent antifibrotic effect. We further identified TNF (tumor necrosis factor)-α and IL (interleukin)-1β as 2 cytokines in M1 media that cause the observed antifibrotic effect. After 7 days of culture in M1 conditioned media, VICs began differentiating into osteoblast-like cells, as measured by increased expression of RUNX2 (runt-related transcription factor 2) and osteopontin. We also identified and validated IL-6 as a critical mediator of the observed pro-osteogenic effect.

CONCLUSIONS

Proinflammatory cytokines in M1 conditioned media inhibit myofibroblast activation in VICs (eg, TNF-α and IL-1β) and promote their osteogenic differentiation (eg, IL-6). Together, our work suggests inflammatory M1 macrophages may drive a myofibroblast-to-osteogenic intermediate VIC phenotype, which may mediate the switch from fibrosis to calcification during aortic valve stenosis progression.

Is improvement in depression in patients attending cardiac rehabilitation with new-onset depressive symptoms determined by patient characteristics?

BACKGROUND

Patients with cardiovascular disease (CVD) commonly experience depressive symptoms which is associated with adverse outcome and increased mortality. Examining the baseline characteristics of cardiac rehabilitation (CR) patients that determine Hospital Anxiety and Depression Scale (HADS) depression outcome may facilitate adjustments in CR programme delivery. This study aims to investigate whether comorbidities, demographic and clinical characteristics of patients, with new-onset post-cardiac event depressive symptoms, determine change in their depression following CR.

METHODS

Analysing the routine practice data of British Heart Foundation National Audit of Cardiac Rehabilitation between April 2012 and March 2018, an observational study was conducted. Patients with new-onset post-cardiac event depressive symptoms and no previous documented history of depression constituted the study population.

RESULTS

The analyses included 64 658 CR patients (66.24±10.69 years, 75% male) with new-onset HADS measures, excluding patients with a history of depression. The comorbidities determining reduced likelihood of improvement in depression outcomes after CR were angina, diabetes, stroke, emphysema and chronic back problems. In addition, higher total number of comorbidities, increased weight, a higher HADS anxiety score, smoking at baseline, physical inactivity, presence of heart failure and being single were other significant determinants. However, receiving coronary artery bypass graft treatment was associated with better improvement.

CONCLUSION

The study identified specific baseline comorbid conditions of patients with new-onset depressive symptoms including angina, diabetes, stroke, emphysema and chronic back problems that were determinants of poorer mental health outcomes (HADS) following CR. Higher total number of comorbidities, increased weight, physical inactivity, smoking, presence of heart failure and being single were other determinants of a negative change in depression. These findings could help CR programmes focus on tailoring the CR intervention around comorbidity, physical activity status, weight management and smoking cessation in patients with new-onset depressive symptoms.

Macrophages Promote Aortic Valve Cell Calcification and Alter STAT3 Splicing

OBJECTIVE

Macrophages have been described in calcific aortic valve disease, but it is unclear if they promote or counteract calcification. We aimed to determine how macrophages are involved in calcification using the Notch1+/- model of calcific aortic valve disease. Approach and Results: Macrophages in wild-type and Notch1+/- murine aortic valves were characterized by flow cytometry. Macrophages in Notch1+/- aortic valves had increased expression of MHCII (major histocompatibility complex II). We then used bone marrow transplants to test if differences in Notch1+/- macrophages drive disease. Notch1+/- mice had increased valve thickness, macrophage infiltration, and proinflammatory macrophage maturation regardless of transplanted bone marrow genotype. In vitro approaches confirm that Notch1+/- aortic valve cells promote macrophage invasion as quantified by migration index and proinflammatory phenotypes as quantified by Ly6C and CCR2 positivity independent of macrophage genotype. Finally, we found that macrophage interaction with aortic valve cells promotes osteogenic, but not dystrophic, calcification and decreases abundance of the STAT3β isoform.

CONCLUSIONS

This study reveals that Notch1+/- aortic valve disease involves increased macrophage recruitment and maturation driven by altered aortic valve cell secretion, and that increased macrophage recruitment promotes osteogenic calcification and alters STAT3 splicing. Further investigation of STAT3 and macrophage-driven inflammation as therapeutic targets in calcific aortic valve disease is warranted.

Relationship between socioeconomic status and incidence of out-of-hospital cardiac arrest is dependent on age

Background

The association between socioeconomic status (SES) and incidence of out-of-hospital cardiac arrest (OHCA) is not fully understood. The aim of this study was to see if area-level socioeconomic differences, measured in terms of area-level income and education, are associated with the incidence of OHCA, and if this relationship is dependent on age.

Methods

We included OHCAs that occurred in Stockholm County between the 1st of January 2006 and the 31st of December 2017, the victims being confirmed residents (n=10 574). We linked the home address to a matching neighbourhood (base unit) via available socioeconomic and demographic information. Socioeconomic variables and incidence rates were assessed by using cross-sectional values at the end of each year. We used zero-inflated negative binomial regression to calculate incidence rate ratios (IRRs).

Results

Among 1349 areas with complete SES information, 10 503 OHCAs occurred between 2006 and 2017. The IRR in the highest versus the lowest SES area was 0.61 (0.50–0.75) among persons in the 0–44 age group. Among patients in the 45–64 age group, the corresponding IRR was 0.55 (0.47–0.65). The highest SES areas versus the lowest showed an IRR of 0.59 (0.50–0.70) in the 65–74 age group. In the two highest age groups, no significant association was seen (75–84 age group: 0.93 (0.80–1.08); 85+ age group: 1.05 (0.84–1.23)). Similar crude patterns were seen among both men and women.

Conclusions

Areas characterised by high SES showed a significantly lower incidence of OHCA. This relationship was seen up to the age of 75, after which the relationship disappeared, suggesting a levelling effect.

Macrophage lineages in heart valve development and disease

Heterogeneous macrophage lineages are present in the aortic and mitral valves of the heart during development and disease. These populations include resident macrophages of embryonic origins and recruited monocyte-derived macrophages prevalent in disease. Soon after birth, macrophages from haematopoietic lineages are recruited to the heart valves, and bone marrow transplantation studies in mice demonstrate that haematopoietic-derived macrophages continue to invest adult valves. During myxomatous heart valve disease, monocyte-derived macrophages are recruited to the heart valves and they contribute to valve degeneration in a mouse model of Marfan syndrome. Here, we review recent studies of macrophage lineages in heart valve development and disease with discussion of clinical significance and therapeutic applications.

Adaptive immune cells in calcific aortic valve disease

Calcific aortic valve disease (CAVD) is highly prevalent and has no pharmaceutical treatment. Surgical replacement of the aortic valve has proved effective in advanced disease but is costly, time limited, and in many cases not optimal for elderly patients. This has driven an increasing interest in noninvasive therapies for patients with CAVD. Adaptive immune cell signaling in the aortic valve has shown potential as a target for such a therapy. Up to 15% of cells in the healthy aortic valve are hematopoietic in origin, and these cells, which include macrophages, T lymphocytes, and B lymphocytes, are increased further in calcified specimens. Additionally, cytokine signaling has been shown to play a causative role in aortic valve calcification both in vitro and in vivo. This review summarizes the physiological presence of hematopoietic cells in the valve, innate and adaptive immune cell infiltration in disease states, and the cytokine signaling pathways that play a significant role in CAVD pathophysiology and may prove to be pharmaceutical targets for this disease in the near future.

Maturation of heart valve cell populations during postnatal remodeling

Heart valve cells mediate extracellular matrix (ECM) remodeling during postnatal valve leaflet stratification, but phenotypic and transcriptional diversity of valve cells in development is largely unknown. Single cell analysis of mouse heart valve cells was used to evaluate cell heterogeneity during postnatal ECM remodeling and leaflet morphogenesis. The transcriptomic analysis of single cells from postnatal day (P)7 and P30 murine aortic (AoV) and mitral (MV) heart valves uncovered distinct subsets of melanocytes, immune and endothelial cells present at P7 and P30. By contrast, interstitial cell populations are different from P7 to P30. P7 valve leaflets exhibit two distinct collagen- and glycosaminoglycan-expressing interstitial cell clusters, and prevalent ECM gene expression. At P30, four interstitial cell clusters are apparent with leaflet specificity and differential expression of complement factors, ECM proteins and osteogenic genes. This initial transcriptomic analysis of postnatal heart valves at single cell resolution demonstrates that subpopulations of endothelial and immune cells are relatively constant throughout postnatal development, but interstitial cell subpopulations undergo changes in gene expression and cellular functions in primordial and mature valves.

The Genetic Regulation of Aortic Valve Development and Calcific Disease

Heart valves are dynamic, highly organized structures required for unidirectional blood flow through the heart. Over an average lifetime, the valve leaflets or cusps open and close over a billion times, however in over 5 million Americans, leaflet function fails due to biomechanical insufficiency in response to wear-and-tear or pathological stimulus. Calcific aortic valve disease (CAVD) is the most common valve pathology and leads to stiffening of the cusp and narrowing of the aortic orifice leading to stenosis and insufficiency. At the cellular level, CAVD is characterized by valve endothelial cell dysfunction and osteoblast-like differentiation of valve interstitial cells. These processes are associated with dysregulation of several molecular pathways important for valve development including Notch, Sox9, Tgfβ, Bmp, Wnt, as well as additional epigenetic regulators. In this review, we discuss the multifactorial mechanisms that contribute to CAVD pathogenesis and the potential of targeting these for the development of novel, alternative therapeutics beyond surgical intervention.

Development of the Myocardial Interstitium

The space between cardiac myocytes is commonly referred-to as the cardiac interstitium (CI). The CI is a unique, complex and dynamic microenvironment in which multiple cell types, extracellular matrix molecules, and instructive signals interact to crucially support heart homeostasis and promote cardiac responses to normal and pathologic stimuli. Despite the biomedical and clinical relevance of the CI, its detailed cellular structure remains to be elucidated. In this review, we will dissect the organization of the cardiac interstitium by following its changing cellular and molecular composition from embryonic developmental stages to adulthood, providing a systematic analysis of the biological components of the CI. The main goal of this review is to contribute to our understanding of the CI roles in health and disease. Anat Rec, 302:58-68, 2019. © 2018 Wiley Periodicals, Inc.

Calcific Aortic Valve Disease: a Developmental Biology Perspective

PURPOSE OF REVIEW

This review aims to highlight the past and more current literature related to the multifaceted pathogenic programs that contribute to calcific aortic valve disease (CAVD) with a focus on the contribution of developmental programs.

RECENT FINDINGS

Calcification of the aortic valve is an active process characterized by calcific nodule formation on the aortic surface leading to a less supple and more stiffened cusp, thereby limiting movement and causing clinical stenosis. The mechanisms underlying these pathogenic changes are largely unknown, but emerging studies have suggested that signaling pathways common to valvulogenesis and bone development play significant roles and include Transforming Growth Factor-β (TGF-β), bone morphogenetic protein (BMP), Wnt, Notch, and Sox9. This comprehensive review of the literature highlights the complex nature of CAVD but concurrently identifies key regulators that can be targeted in the development of mechanistic-based therapies beyond surgical intervention to improve patient outcome.

Monocytes and Macrophages in Heart Valves: Uninvited Guests or Critical Performers?

Monocytes and macrophages are critical components of the myeloid niche of the innate immune system. In addition to traditional roles as phagocytes, this subsection of innate immunity has been implicated in its ability to regulate tissue homeostasis and inflammation across diverse physiological systems. Recent emergence of discriminatory features within the monocyte/macrophage niche within the last 5 years has helped to clarify specific function(s) of the subpopulations of these cells. It is becoming increasingly aware that these cells are likely implicated in valve development and disease. This review seeks to use current literature and opinions to show the diverse roles and potential contributions of this niche throughout valvulogenic processes, adult homeostatic function, valve disease mechanisms, and tissue engineering approaches.

Conditional deletion of RB1 in the Tie2 lineage leads to aortic valve regurgitation

Objective

Aortic valve disease is a complex process characterized by valve interstitial cell activation, disruption of the extracellular matrix culminating in valve mineralization occurring over many years. We explored the function of the retinoblastoma protein (pRb) in aortic valve disease, given its critical role in mesenchymal cell differentiation including bone development and mineralization.

Approach and results

We generated a mouse model of conditional pRb knockout (cKO) in the aortic valve regulated by Tie2-Cre-mediated excision of floxed RB1 alleles. Aged pRb cKO animals showed significantly more aortic valve regurgitation by echocardiography compared to pRb het control animals. The pRb cKO aortic valves had increased leaflet thickness without increased cellular proliferation. Histologic studies demonstrated intense α-SMA expression in pRb cKO leaflets associated with disorganized extracellular matrix and increased leaflet stiffness. The pRb cKO mice also showed increased circulating cytokine levels.

Conclusions

Our studies demonstrate that pRb loss in the Tie2-lineage that includes aortic valve interstitial cells is sufficient to cause age-dependent aortic valve dysfunction.