Decreased prevalence of new-onset adhesive capsulitis in patients prescribed angiotensin receptor blockers

BACKGROUND

Angiotensin receptor blockers (ARBs) are commonly prescribed antihypertensive agents that have well-known antifibrotic properties. The purpose of this study was to examine the association between ARB use and the rates of new-onset adhesive capsulitis as well as adhesive capsulitis requiring operative treatment.

METHODS

Using a large national insurance database, a randomly generated cohort of patients with at least 3 continuous months of ARB use between January 2010 and December 2019 (n = 1,000,000) was compared to a separate randomly generated cohort without ARB use (n = 3,000,000). Rates of newly diagnosed adhesive capsulitis and associated manipulation under anesthesia (MUA) and/or arthroscopic capsulotomy were calculated over a 1- and 2-year period following the completion of at least 3 continuous months of ARB therapy. Rates were compared using multivariable logistic regression to control for demographics and comorbidities. Both unadjusted and adjusted odds ratios and 95% confidence intervals were calculated and reported for each comparison. Statistical significance was set at P <.05.

RESULTS

The mean age in the ARB cohort was 61.8 years (standard deviation [SD] = 10.0), whereas in the control cohort, it was 54.8 years (SD = 12.3) (P < .001). The ARB cohort had significantly lower rates of newly diagnosed adhesive capsulitis compared with the control cohort at both 1 year (0.15% vs. 0.55%, P < .001) and 2 years (0.3% vs. 0.78%, P < .001). Similar findings were observed for the arthroscopic capsular release/MUA cohort associated with adhesive capsulitis. After adjusting for confounding factors, the lower rates of adhesive capsulitis and arthroscopic capsular release/MUA associated with adhesive capsulitis in the ARB cohort remained statistically significant (P < .001).

CONCLUSION

Patients prescribed ARBs experienced a decreased rate of newly diagnosed adhesive capsulitis, as well as adhesive capsulitis requiring surgical intervention when compared to a control cohort. These findings suggest a potential protective effect of ARBs against the development of adhesive capsulitis. Further investigations are warranted to elucidate the underlying mechanisms and establish a causal relationship.

Integrated machine learning and Mendelian randomization reveal PALMD as a prognostic biomarker for nonspecific orbital inflammation

BACKGROUND

Nonspecific Orbital Inflammation (NSOI) remains a perplexing enigma among proliferative inflammatory disorders. Its etiology is idiopathic, characterized by distinctive and polymorphous lymphoid infiltration within the orbital region. Preliminary investigations suggest that PALMD localizes within the cytosol, potentially playing a crucial role in cellular processes, including plasma membrane dynamics and myogenic differentiation. The potential of PALMD as a biomarker for NSOI warrants meticulous exploration.

METHODS

PALMD was identified through the intersection analysis of common DEGs from datasets GSE58331 and GSE105149 from the GEO database, alongside immune-related gene lists from the ImmPort database, using Lasso regression and SVM-RFE analysis. GSEA and GSVA were conducted with gene sets co-expressed with PALMD. To further investigate the correlation between PALMD and immune-related biological processes, the CIBERSORT algorithm and ESTIMATE method were employed to evaluate immune microenvironment characteristics of each sample. The expression levels of PALMD were subsequently validated using GSE105149.

RESULTS

Among the 314 DEGs identified, several showed significant differences. Lasso and SVM-RFE algorithms pinpointed 15 hub genes. Functional analysis of PALMD emphasized its involvement in cell-cell adhesion, leukocyte migration, and leukocyte-mediated immunity. Enrichment analysis revealed that gene sets positively correlated with PALMD were enriched in immune-related pathways. Immune infiltration analysis indicated that resting dendritic cells, resting mast cells, activated NK cells, and plasma cells positively associate with PALMD expression. Conversely, naive B cells, activated dendritic cells, M0 and M1 macrophages, activated mast cells, activated CD4 memory T cells, and naive CD4 T cells showed a negative correlation with PALMD expression. PALMD demonstrated significant diagnostic potential in differentiating NSOI.

CONCLUSIONS

This study identifies PALMD as a potential biomarker linked to NSOI, providing insights into its pathogenesis and offering new avenues for tracking disease progression.

Angiotensin II Receptor Blockers Are Associated With Reduced Valvular Fibrosis in Women With Aortic Stenosis

BACKGROUND

Angiotensin receptor blockers (ARBs) may slow down the progression of aortic stenosis (AS) through their antifibrotic effect. Women present more valvular fibrosis than men, so ARBs may have more effect in females. Our aim was to assess the impact of ARBs on the remodelling of the aortic valve in men and women.

METHODS

We included patients who had an aortic valve replacement with or without coronary bypass grafting from 2006 to 2013. Patients with missing echocardiographic or histologic data were excluded. Warren-Yong and fibrosis scores of the explanted valves were performed. Patients were divided into 4 phenotypes according to their Warren-Yong and fibrosis scores: mild calcification/fibrosis, severe calcification/fibrosis group, predominant fibrosis group, predominant calcification group.

RESULTS

Among the 1321 included patients, the vast majority (89%) has severe AS. Patients in the predominant fibrosis group, compared with the predominant calcium group, were more often female (39% vs 31%; P = 0.008) with bicuspid valves (44% vs 34%; P = 0.002), and less often used ARBs (25% vs 30%; P = 0.046). Female sex was independently associated with being in the predominant fibrosis group (odds ratio 1.45, 95% confidence interval 1.08-1.95; P = 0.01), with a significant interaction between female sex and ARBs. Women taking ARBs compared with women not taking ARBs had significantly lower fibrosis scores (P < 0.001). This difference was not seen in men.

CONCLUSIONS

In this large series of patients with moderate-severe AS, among the women there was a negative association between intake of ARBs and valvular fibrosis. Thus, the possible effects of ARBs may be sex specific, with a larger therapeutic role in women.

The effect of immunomodulatory drugs on aortic stenosis: a Mendelian randomisation analysis

There are currently no approved pharmacological treatment options for aortic stenosis (AS), and there are limited identified drug targets for this chronic condition. It remains unclear whether inflammation plays a role in AS pathogenesis and whether immunomodulation could become a therapeutic target. We evaluated the potentially causal association between inflammation and AS by investigating the genetically proxied effects of tocilizumab (IL6 receptor, IL6R, inhibitor), canakinumab (IL1β inhibitor) and colchicine (β-tubulin inhibitor) through a Mendelian randomisation (MR) approach. Genetic proxies for these drugs were identified as single nucleotide polymorphisms (SNPs) in the gene, enhancer or promoter regions of IL6R, IL1β or β-tubulin gene isoforms, respectively, that were significantly associated with serum C-reactive protein (CRP) in a large European genome-wide association study (GWAS; 575,531 participants). These were paired with summary statistics from a large GWAS of AS in European patients (653,867 participants) to then perform primary inverse-variance weighted random effect and sensitivity MR analyses for each exposure. This analysis showed that genetically proxied tocilizumab was associated with reduced risk of AS (OR 0.56, 95% CI 0.45-0.70 per unit decrease in genetically predicted log-transformed CRP). Genetically proxied canakinumab was not associated with risk of AS (OR 0.80, 95% CI 0.51-1.26), and only one suitable SNP was identified to proxy the effect of colchicine (OR 34.37, 95% CI 1.99-592.89). The finding that genetically proxied tocilizumab was associated with reduced risk of AS is concordant with an inflammatory hypothesis of AS pathogenesis. Inhibition of IL6R may be a promising therapeutic target for AS management.

Spontaneous Epiretinal Membrane Resolution and Angiotensin Receptor Blockers: Case Observation, Literature Review and Perspectives

INTRODUCTION

Epiretinal membrane (ERM) is a relatively common condition affecting the macula. When symptoms become apparent and compromise a patient's quality of vision, the only therapeutic approach available today is surgery with a vitrectomy and peeling of the ERM. Angiotensin receptor blockers (ARBs) and angiotensin-converting enzyme inhibitors (ACE-Is) reduce the effect of angiotensin II, limit the amount of fibrosis, and demonstrate consequences on fibrinogenesis in the human body. Case Description and Materials and Methods: A rare case of spontaneous ERM resolution with concomitant administration of ARB is reported. The patient was set on ARB treatment for migraines and arterial hypertension, and a posterior vitreous detachment was already present at the first diagnosis of ERM. The scientific literature addressing the systemic relationship between ARB, ACE-Is, and fibrosis in the past 25 years was searched in the PubMed, Medline, and EMBASE databases.

RESULTS

In total, 38 and 16 original articles have been selected for ARBs and ACE-Is, respectively, in regard to fibrosis modulation.

CONCLUSION

ARBs and ACE-Is might have antifibrotic activity on ERM formation and resolution. Further clinical studies are necessary to explore this phenomenon.

Calcific aortic valve disease: mechanisms, prevention and treatment

Calcific aortic valve disease (CAVD) is the most common disorder affecting heart valves and is characterized by thickening, fibrosis and mineralization of the aortic valve leaflets. Analyses of surgically explanted aortic valve leaflets have shown that dystrophic mineralization and osteogenic transition of valve interstitial cells co-occur with neovascularization, microhaemorrhage and abnormal production of extracellular matrix. Age and congenital bicuspid aortic valve morphology are important and unalterable risk factors for CAVD, whereas additional risk is conferred by elevated blood pressure and plasma lipoprotein(a) levels and the presence of obesity and diabetes mellitus, which are modifiable factors. Genetic and molecular studies have identified that the NOTCH, WNT-β-catenin and myocardin signalling pathways are involved in the control and commitment of valvular cells to a fibrocalcific lineage. Complex interactions between valve endothelial and interstitial cells and immune cells promote the remodelling of aortic valve leaflets and the development of CAVD. Although no medical therapy is effective for reducing or preventing the progression of CAVD, studies have started to identify actionable targets.

Cellular Senescence, Aging and Non-Aging Processes in Calcified Aortic Valve Stenosis: From Bench-Side to Bedside

Aortic valve stenosis (AS) is the most common valvular heart disease. The incidence of AS increases with age, however, a significant proportion of elderly people have no significant AS, indicating that both aging and nonaging pathways are involved in the pathomechanism of AS. Age-related and stress-induced cellular senescence accompanied by further active processes represent the key elements of AS pathomechanism. The early stage of aortic valve degeneration involves dysfunction and disruption of the valvular endothelium due to cellular senescence and mechanical stress on blood flow. These cells are replaced by circulating progenitor cells, but in an age-dependent decelerating manner. When endothelial denudation is no longer replaced by progenitor cells, the path opens for focal lipid deposition, initiating subsequent oxidation, inflammation and micromineralisation. Later stages of AS feature a complex active process with extracellular matrix remodeling, fibrosis and calcification. Echocardiography is the gold standard method for diagnosing aortic valve disease, although computed tomography and cardiac magnetic resonance are useful additional imaging methods. To date, no medical treatment has been proven to halt the progression of AS. Elucidation of differences and similarities between vascular and valvular calcification pathomechanisms may help to find effective medical therapy and reduce the increasing health burden of the disease.

IL6 gene polymorphism association with calcific aortic valve stenosis and influence on serum levels of interleukin-6

Aortic valve stenosis is the most frequent valve disease in developed countries and its prevalence will increase with population aging. There is still no pharmaceutical treatment nor biomarker to determine the susceptibility to develop aortic stenosis. Therefore, we analyzed the association of polymorphisms in risk loci with calcific aortic stenosis. Patients with aortic valve disease were genotyped for PALMD rs6702619, LPA rs10455872, and IL6 rs1800795 polymorphisms and circulating levels of interleukin-6 (IL-6) were measured. Calcium content of leaflets obtained in valve replacement surgeries was determined by micro-computed tomography. In the genotyping of 578 individuals, we found significant association between PALMD and IL6 polymorphisms and aortic stenosis in patients with tricuspid aortic valve, independently of other potentially confounding variables such as age and dyslipidemia. There was no association of these polymorphisms with valve calcium content, but this value correlated with the mean aortic pressure gradient (r = 0.44; P < 0.001). The CC genotype of IL6 polymorphism was associated with higher levels of serum IL-6 compared to other genotypes (23.5 vs. 10.5 pg/ml, respectively; P = 0.029). Therefore, patients carrying the CC genotype of IL6 rs1800795 polymorphism present higher levels of circulating IL-6 and this could contribute to the severity of the aortic valve stenosis. Our results agree with the identification of IL6 as a locus risk for stenosis and also with the intervention of this cytokine in aortic valve calcification. A more exhaustive follow-up of those patients carrying risk genotypes is therefore recommended.

Correlation Between Cardiac Computed Tomography and Histopathology for Evaluating Patients with Aortic Valve Disease

BACKGROUND

The use of cardiac computed tomography (cardiac CT) and the quantification of the Agatston score for the evaluation of calcium of the aortic valve (AVC) has increased in different clinical contexts for diagnostic and prognostic purposes. This study aims to evaluate the correlation between cardiac CT and histopathology for the quantification of AVC.

METHODS

Ninety patients diagnosed with severe aortic valve dysfunction, of any etiology and regardless of the predominant type of injury, were included. Before the surgical event, a Cardiac CT were performed with Agatston Score measurement. The removed native valve was evaluated by a Pathologist, who provided a qualitative and quantitative evaluation of valve calcium. Calcium density was also analyzed by quantifying the area in pixel units obtained from photomicrographs. Follow-up was performed for four years after the aortic valve replacement.

RESULTS

Ninety patients were analyzed. The degenerative etiology predominated 63.3% (57 patients). The calcium load was different for the gender (p = 0.01) and type of valve injury (p = 0.0013). There was a positive correlation between the Agatston score, and the percentage of calcium reported by the pathologist in a conventional qualitative way (rs = 0.75, p < 0.001) and between the AVC and the Cote et al. score (rs = 0.77, p < 0.001). There was no difference in survival after aortic valve replacement concerning valve calcium load. Left ventricular dysfunction showed a significant difference in survival (p = 0.003, Log-rank).

CONCLUSION

There is a moderately high correlation between the Agatston score quantified by Cardiac CT and the histopathological evaluation. The severity of the calcification did not prove to be a predictor of death in the postsurgical follow-up.

Towards Personalized Therapy of Aortic Stenosis

Calcific aortic stenosis (CAS) is the most common cause of acquired valvular heart disease in adults with no available pharmacological treatment to inhibit the disease progression to date. This review provides an up-to-date overview of current knowledge of molecular mechanisms underlying CAS pathobiology and the related treatment pathways. Particular attention is paid to current randomized trials investigating medical treatment of CAS, including strategies based on lipid-lowering and antihypertensive therapies, phosphate and calcium metabolism, and novel therapeutic targets such as valvular oxidative stress, coagulation proteins, matrix metalloproteinases, and accumulation of advanced glycation end products.

Contrast-enhanced computed tomography assessment of aortic stenosis

OBJECTIVES

Non-contrast CT aortic valve calcium scoring ignores the contribution of valvular fibrosis in aortic stenosis. We assessed aortic valve calcific and non-calcific disease using contrast-enhanced CT.

METHODS

This was a post hoc analysis of 164 patients (median age 71 (IQR 66-77) years, 78% male) with aortic stenosis (41 mild, 89 moderate, 34 severe; 7% bicuspid) who underwent echocardiography and contrast-enhanced CT as part of imaging studies. Calcific and non-calcific (fibrosis) valve tissue volumes were quantified and indexed to annulus area, using Hounsfield unit thresholds calibrated against blood pool radiodensity. The fibrocalcific ratio assessed the relative contributions of valve fibrosis and calcification. The fibrocalcific volume (sum of indexed non-calcific and calcific volumes) was compared with aortic valve peak velocity and, in a subgroup, histology and valve weight.

RESULTS

Contrast-enhanced CT calcium volumes correlated with CT calcium score (r=0.80, p<0.001) and peak aortic jet velocity (r=0.55, p<0.001). The fibrocalcific ratio decreased with increasing aortic stenosis severity (mild: 1.29 (0.98-2.38), moderate: 0.87 (1.48-1.72), severe: 0.47 (0.33-0.78), p<0.001) while the fibrocalcific volume increased (mild: 109 (75-150), moderate: 191 (117-253), severe: 274 (213-344) mm³/cm²). Fibrocalcific volume correlated with ex vivo valve weight (r=0.72, p<0.001). Compared with the Agatston score, fibrocalcific volume demonstrated a better correlation with peak aortic jet velocity (r=0.59 and r=0.67, respectively), particularly in females (r=0.38 and r=0.72, respectively).

CONCLUSIONS

Contrast-enhanced CT assessment of aortic valve calcific and non-calcific volumes correlates with aortic stenosis severity and may be preferable to non-contrast CT when fibrosis is a significant contributor to valve obstruction.

Calcific aortic valve disease: from molecular and cellular mechanisms to medical therapy

Calcific aortic valve disease (CAVD) is a highly prevalent condition that comprises a disease continuum, ranging from microscopic changes to profound fibro-calcific leaflet remodelling, culminating in aortic stenosis, heart failure, and ultimately premature death. Traditional risk factors, such as hypercholesterolaemia and (systolic) hypertension, are shared among atherosclerotic cardiovascular disease and CAVD, yet the molecular and cellular mechanisms differ markedly. Statin-induced low-density lipoprotein cholesterol lowering, a remedy highly effective for secondary prevention of atherosclerotic cardiovascular disease, consistently failed to impact CAVD progression or to improve patient outcomes. However, recently completed phase II trials provide hope that pharmaceutical tactics directed at other targets implicated in CAVD pathogenesis offer an avenue to alter the course of the disease non-invasively. Herein, we delineate key players of CAVD pathobiology, outline mechanisms that entail compromised endothelial barrier function, and promote lipid homing, immune-cell infiltration, and deranged phospho-calcium metabolism that collectively perpetuate a pro-inflammatory/pro-osteogenic milieu in which valvular interstitial cells increasingly adopt myofibro-/osteoblast-like properties, thereby fostering fibro-calcific leaflet remodelling and eventually resulting in left ventricular outflow obstruction. We provide a glimpse into the most promising targets on the horizon, including lipoprotein(a), mineral-binding matrix Gla protein, soluble guanylate cyclase, dipeptidyl peptidase-4 as well as candidates involved in regulating phospho-calcium metabolism and valvular angiotensin II synthesis and ultimately discuss their potential for a future therapy of this insidious disease.

Interferons Are Pro-Inflammatory Cytokines in Sheared-Stressed Human Aortic Valve Endothelial Cells

Calcific aortic valve disease (CAVD) is an athero-inflammatory process. Growing evidence supports the inflammation-driven calcification model, mediated by cytokines such as interferons (IFNs) and tumor necrosis factor (TNF)-α. Our goal was investigating IFNs' effects in human aortic valve endothelial cells (VEC) and the potential differences between aortic (aVEC) and ventricular (vVEC) side cells. The endothelial phenotype was analyzed by Western blot, qPCR, ELISA, monocyte adhesion, and migration assays. In mixed VEC populations, IFNs promoted the activation of signal transducers and activators of transcription-1 and nuclear factor-κB, and the subsequent up-regulation of pro-inflammatory molecules. Side-specific VEC were activated with IFN-γ and TNF-α in an orbital shaker flow system. TNF-α, but not IFN-γ, induced hypoxia-inducible factor (HIF)-1α stabilization or endothelial nitric oxide synthase downregulation. Additionally, IFN-γ inhibited TNF-α-induced migration of aVEC. Also, IFN-γ triggered cytokine secretion and adhesion molecule expression in aVEC and vVEC. Finally, aVEC were more prone to cytokine-mediated monocyte adhesion under multiaxial flow conditions as compared with uniaxial flow. In conclusion, IFNs promote inflammation and reduce TNF-α-mediated migration in human VEC. Moreover, monocyte adhesion was higher in inflamed aVEC sheared under multiaxial flow, which may be relevant to understanding the initial stages of CAVD.

NOTCH Signaling in Aortic Valve Development and Calcific Aortic Valve Disease

NOTCH intercellular signaling mediates the communications between adjacent cells involved in multiple biological processes essential for tissue morphogenesis and homeostasis. The NOTCH1 mutations are the first identified human genetic variants that cause congenital bicuspid aortic valve (BAV) and calcific aortic valve disease (CAVD). Genetic variants affecting other genes in the NOTCH signaling pathway may also contribute to the development of BAV and the pathogenesis of CAVD. While CAVD occurs commonly in the elderly population with tri-leaflet aortic valve, patients with BAV have a high risk of developing CAVD at a young age. This observation indicates an important role of NOTCH signaling in the postnatal homeostasis of the aortic valve, in addition to its prenatal functions during aortic valve development. Over the last decade, animal studies, especially with the mouse models, have revealed detailed information in the developmental etiology of congenital aortic valve defects. In this review, we will discuss the molecular and cellular aspects of aortic valve development and examine the embryonic pathogenesis of BAV. We will focus our discussions on the NOTCH signaling during the endocardial-to-mesenchymal transformation (EMT) and the post-EMT remodeling of the aortic valve. We will further examine the involvement of the NOTCH mutations in the postnatal development of CAVD. We will emphasize the deleterious impact of the embryonic valve defects on the homeostatic mechanisms of the adult aortic valve for the purpose of identifying the potential therapeutic targets for disease intervention.

Changing epidemiology of calcific aortic valve disease: 30-year trends of incidence, prevalence, and deaths across 204 countries and territories

Calcific aortic valve disease (CAVD) is associated with increased morbidity and mortality. We aimed to elucidate the 30-year epidemiology of CAVD globally. Global CAVD incidence, prevalence, and deaths increased 3.51-, 4.43-, and 1.38-fold from 1990 to 2019, respectively, without any decreasing trends, even after age standardization. In 2019, Slovenia had the highest age-standardized rate (ASR) of CAVD incidence (62.21/100,000 persons) and prevalence (1,080.06/100,000) whereas Cyprus had the highest ASR of deaths (8.20/100,000). Population aging was an important contributor to incidence. Compared with women, more men had CAVD and men had earlier peaks in disease prevalence. High systolic blood pressure, diet high in sodium, and lead exposure were the main risk factors for deaths owing to CAVD. The estimated annual percentage change, a measure to estimate the variation of ASR, was significantly associated with the ASR and sociodemographic index (SDI) in 2019 for incidence and prevalence across all 204 countries and territories (all p<0.0001). With increased lifespan and risk factors, the overall burden of CAVD is high and remains on the rise, with differences by sex, age, and SDI level. Our findings serve to sound the alarm for organizations, institutions, and resources whose primary purpose is to improve human health.

Current Evidence and Future Perspectives on Pharmacological Treatment of Calcific Aortic Valve Stenosis

Calcific aortic valve stenosis (CAVS), the most common heart valve disease, is characterized by the slow progressive fibro-calcific remodeling of the valve leaflets, leading to progressive obstruction to the blood flow. CAVS is an increasing health care burden and the development of an effective medical treatment is a major medical need. To date, no effective pharmacological therapies have proven to halt or delay its progression to the severe symptomatic stage and aortic valve replacement represents the only available option to improve clinical outcomes and to increase survival. In the present report, the current knowledge and latest advances in the medical management of patients with CAVS are summarized, placing emphasis on lipid-lowering agents, vasoactive drugs, and anti-calcific treatments. In addition, novel potential therapeutic targets recently identified and currently under investigation are reported.

Age, Sex, and Valve Phenotype Differences in Fibro-Calcific Remodeling of Calcified Aortic Valve

Background

In calcific aortic valve disease on tricuspid aortic valves (TAVs), men have higher aortic valve calcification and less fibrosis than women. However, little is known in bicuspid aortic valves (BAV). We thus aimed to investigate the impact of age, sex, and valve phenotype (TAVs versus BAVs) on fibro‐calcific remodeling in calcific aortic valve disease.

Methods and Results

We included 2 cohorts: 411 patients who underwent multidetector computed tomography (37% women) for aortic valve calcification density assessment and 138 explanted aortic valves (histological cohort; 50% women). The cohorts were divided in younger (<60 years old) or older patients with BAV (≥60 years old), and TAV patients. In each group, women and men were matched. Women presented less aortic valve calcification density than men in each group of the multidetector computed tomography cohort (all P≤0.01). Moreover, in women, younger patients with BAV had the lowest aortic valve calcification density (both P=0.02). In multivariate analysis, aortic valve calcification density correlated with age (β estimate±standard error: 6.5±1.8; P=0.0004) and male sex (109.2±18.4; P<0.0001), and there was a trend with TAVs (41.5±23.0; P=0.07). Women presented a higher collagen content than men (77.8±10.8 versus 69.9±12.9%; P<0.001) in the entire cohort. In women, younger patients with BAV had denser connective tissue than TAV and older patients with BAV (both P≤0.05), while no difference was observed between men.

Conclusions

In calcific aortic valve disease, women had less calcification and more fibrotic remodeling than men, regardless of the phenotype of the valve or age of the patient. Moreover, younger women with BAVs had less valve calcification. Thus, mineralization/fibrosis of the aortic valve is likely to have sex/age‐specific mechanisms and be influenced by the valve morphology.

Association of aortic valve calcification and vitamin K antagonist treatment

Aims 

Vitamin K antagonists (VKAs) are suspected of causing aortic valve calcification (AVC). The objective of this study was to clarify whether patients undergoing VKA treatment have increased AVC scores compared to patients treated with new oral anticoagulants (NOACs) and patients who never have been treated with VKA/NOAC.

Methods and results 

We included participants from the population-based DANCAVAS trial (n = 15 048). Information on confounders was collected, and the AVC scores were measured on non-contrast computed tomography scans. The participants’ medication data, including VKA and NOAC data, were collected from the Danish National Health Service Prescription Database. The final population consisted of 14 604 participants (67.4 years, 95% men) of whom 873 had been treated with VKA and 602 with NOAC. The association between AVC score and duration of anticoagulant use was investigated in an adjusted zero-inflated negative binomial regression model. For every year treated with VKA, the AVC score increased, on average, by 6% [ratio of expected counts (RECs) = 1.06; 95% confidence interval (CI) 1.02–1.10] compared to non-use. The results were consistent in sensitivity analyses excluding patients with known cardiovascular disease and statin users (REC = 1.07; 95% CI 1.02–1.11 and REC = 1.10; 95% CI 1.03–1.17, respectively). NOAC treatment was not significantly associated with AVC score in any of the corresponding models (REC = 1.03, 1.02, and 0.96).

Conclusion 

Compared to no treatment with anticoagulants, VKA use was associated with increased AVC score, while a similar association could not be established for NOAC.

Liraglutide attenuates cardiac remodeling and improves heart function after abdominal aortic constriction through blocking angiotensin II type 1 receptor in rats

Objective

Angiotensin II (Ang II) is known to contribute to the pathogenesis of heart failure by eliciting cardiac remodeling and dysfunction. The glucagon-like peptide-1 (GLP-1) has been shown to exert cardioprotective effects in animals and patients. This study investigates whether GLP-1 receptor agonist liraglutide inhibits abdominal aortic constriction (AAC)-induced cardiac fibrosis and dysfunction through blocking Ang II type 1 receptor (AT1R) signaling.

Methods

Sprague-Dawley rats were subjected to sham operation and abdominal aortic banding procedure for 16 weeks. In treated rats, liraglutide (0.3 mg/kg) was subcutaneously injected twice daily or telmisartan (10 mg/kg/day), the AT1R blocker, was administered by gastric gavage.

Results

Relative to the animals with AAC, liraglutide reduced protein level of the AT1R and upregulated the AT2R, as evidenced by reduced ratio of AT1R/AT2R (0.59±0.04 vs. 0.91±0.06, p<0.05). Furthermore, the expression of angiotensin converting enzyme 2 was upregulated, tissue levels of malondialdehyde and B-type natriuretic peptide were reduced, and superoxide dismutase activity was increased. Along with a reduction in HW/BW ratio, cardiomyocyte hypertrophy was inhibited. In coincidence with these changes, liraglutide significantly decreased the populations of macrophages and myofibroblasts in the myocardium, which were accompanied by reduced protein levels of transforming growth factor beta1, Smad2/3/4, and upregulated smad7. The synthesis of collagen I and III was inhibited and collagen-rich fibrosis was attenuated. Consistent with these findings, cardiac systolic function was preserved, as shown by increased left ventricular systolic pressure (110±5 vs. 99±2 mmHg, p<0.05), ejection fraction (83%±2% vs. 69%±4%, p<0.05) and fraction shortening (49%±2% vs. 35%±3%, p<0.05). Treatment with telmisartan provided a comparable level of protection as compared with liraglutide in all the parameters measured.

Conclusion

Taken together, liraglutide ameliorates cardiac fibrosis and dysfunction, potentially via suppressing the AT1R-mediated events. These data indicate that liraglutide might be selected as an add-on drug to prevent the progression of heart failure.

Aortic stenosis and diabetes mellitus: An ominous combination

Aortic stenosis and diabetes mellitus are both progressive diseases which, if left untreated, result in significant morbidity and mortality. There is evidence that the prevalence of diabetes is substantially increased in patients with aortic stenosis and those with diabetes have increased rates of progression from mild to severe aortic stenosis. There are good data supporting the hypothesis that aortic stenosis and diabetes mellitus are associated with diabetes mellitus being detrimental towards the quality of life and survival of patients. Thus, a thorough understanding of the pathogenesis of both of these disease processes and the relationship between them aids in designing appropriate preventive and therapeutic approaches. This review aims to give a comprehensive and up-to-date insight into the influence of diabetes mellitus on patients with degenerative aortic stenosis, as well as the prognosis and therapeutic approach to these patients.

Targeting the autotaxin - Lysophosphatidic acid receptor axis in cardiovascular diseases

Lysophosphatidic acid (LPA) is a well-characterized bioactive lipid mediator, which is involved in development, physiology, and pathological processes of the cardiovascular system. LPA can be produced both inside cells and in biological fluids. The majority of extracellularLPAis produced locally by the secreted lysophospholipase D, autotaxin (ATX), through its binding to various β integrins or heparin sulfate on cell surface and hydrolyzing various lysophospholipids. LPA initiates cellular signalling pathways upon binding to and activation of its G protein-coupled receptors (LPA1-6). LPA has potent effects on various blood cells and vascular cells involved in the development of cardiovascular diseases such as atherosclerosis and aortic valve sclerosis. LPA signalling drives cell migration and proliferation, cytokine production, thrombosis, fibrosis, as well as angiogenesis. For instance, LPA promotes activation and aggregation of platelets through LPA5, increases expression of adhesion molecules in endothelial cells, and enhances expression of tissue factor in vascular smooth muscle cells. Furthermore, LPA induces differentiation of monocytes into macrophages and stimulates oxidized low-density lipoproteins (oxLDLs) uptake by macrophages to form foam cells during formation of atherosclerotic lesions through LPA1-3. This review summarizes recent findings of the roles played by ATX, LPA and LPA receptors (LPARs) in atherosclerosis and calcific aortic valve disease. Targeting the ATX-LPAR axis may have potential applications for treatment of patients suffering from various cardiovascular diseases.

Calcific aortic valve stenosis: hard disease in the heart: A biomolecular approach towards diagnosis and treatment

Calcific aortic valve stenosis (CAVS) is common in the ageing population and set to become an increasing economic and health burden. Once present, it inevitably progresses and has a poor prognosis in symptomatic patients. No medical therapies are proven to be effective in holding or reducing disease progression. Therefore, aortic valve replacement remains the only available treatment option. Improved knowledge of the mechanisms underlying disease progression has provided us with insights that CAVS is not a passive disease. Rather, CAVS is regulated by numerous mechanisms with a key role for calcification. Aortic valve calcification (AVC) is actively regulated involving cellular and humoral factors that may offer targets for diagnosis and intervention. The discovery that the vitamin K-dependent proteins are involved in the inhibition of AVC has boosted our mechanistic understanding of this process and has opened up novel avenues in disease exploration. This review discusses processes involved in CAVS progression, with an emphasis on recent insights into calcification, methods for imaging calcification activity, and potential therapeutic options.

Degenerative Aortic Stenosis, Dyslipidemia and Possibilities of Medical Treatment

Degenerative aortic stenosis (DAS) is the most frequently diagnosed heart valve disease in Europe and North America. DAS is a chronic progressive disease which resembles development of atherosclerosis. Endothelial dysfunction, lipid infiltration, calcification and ossification are evidenced in both diseases. The same risk factors such as older age, male sex, smoking, and elevated levels of lipids are identified. The effect of smoking, visceral obesity, metabolic syndrome, hypercholesterolemia, low-density lipoprotein, high-density lipoprotein, lipoprotein(a), adiponectin and apolipoprotein(a) on development of DAS are being studied. The search for genetic ties between disorders of lipid metabolism and DAS has been started. DAS is characterized by a long symptom-free period which can last for several decades. Aortic valve replacement surgery is necessary when the symptoms occur. The lipid-lowering therapy effect on stopping or at least slowing down the progression of DAS was studied. However, the results of the conducted clinical trials are controversial. In addition, calcium homeostasis, bone metabolism and calcinosis-reducing medication are being studied. Although prospective randomized clinical trials have not demonstrated any positive effect of statins used for slowing progression of the disease, statins are still recommended for patients with dyslipidemia. Recent study has suggested that a specific modification of treatment, based on severity of disease, may have a beneficial effect in patients with aortic sclerosis and mild DAS. New clinical studies analyzing new treatment possibilities which could correct the natural course of the disease and reduce the need for aortic valve replacement by surgery or transcatheter treatment interventions are needed.

Elevated Serotonin Interacts with Angiotensin-II to Result in Altered Valve Interstitial Cell Contractility and Remodeling

While the valvulopathic effects of serotonin (5HT) and angiotensin-II (Ang-II) individually are known, it was not clear how 5HT and Ang-II might interact, specifically in the context of the mechanobiological responses due to altered valve mechanics potentiated by these molecules. In this context, the hypothesis of this study was that increased serotonin levels would result in accelerated progression toward disease in the presence of angiotensin-II-induced hypertension. C57/BL6 J mice were divided into four groups and subcutaneously implanted with osmotic pumps containing: PBS (control), 5HT (2.5 ng/kg/min), Ang-II (400 ng/kg/min), and 5HT + Ang-II (combination). Blood pressure was monitored using the tail cuff method. Echocardiography was performed on the mice before surgery and every week thereafter to assess ejection fraction. After three weeks, the mice were sacrificed and their hearts excised, embedded and sectioned for analysis of the aortic valves via histology and immunohistochemistry. In separate experiments, porcine valve interstitial cells (VICs) were directly stimulated with 5HT (10^-7 M), Ang-II (100 nM) or both and assayed for cellular contractility, cytoskeletal organization and collagen remodeling. After three weeks, average systolic blood pressure was significantly increased in the 5HT, Ang-II and combination groups compared to control. Echocardiographic analysis demonstrated significantly reduced ejection fraction in Ang-II and the combination groups. H&E staining demonstrated thicker leaflets in the combination groups, suggesting a more aggressive remodeling process. Picrosirius red staining and image analysis suggested that the Ang-II and combination groups had the largest proportion of thicker collagen fibers. VIC orientation, cellular contractility and collagen gene expression was highest for the 5HT + Ang-II combination treatment compared to all other groups. Overall, our results suggest that 5HT and Ang-II interact to result in significantly detrimental alteration of function and remodeling in the valve.

Sex-Related Discordance Between Aortic Valve Calcification and Hemodynamic Severity of Aortic Stenosis: Is Valvular Fibrosis the Explanation?

RATIONALE

Calcific aortic stenosis (AS) is characterized by calcium deposition in valve leaflets. However, women present lower aortic valve calcification loads than men for the same AS hemodynamic severity.

OBJECTIVE

We, thus, aimed to assess sex differences in aortic valve fibrocalcific remodeling.

METHODS AND RESULTS

One hundred and twenty-five patients underwent Doppler echocardiography and multidetector computed tomography within 3 months before aortic valve replacement. Explanted stenotic tricuspid aortic valves were weighed, and fibrosis degree was determined. Sixty-four men and 39 women were frequency matched for age, body mass index, hypertension, renal disease, diabetes mellitus, and AS severity. Mean age (75±9 years), mean gradient (41±18 mm Hg), and indexed aortic valve area (0.41±0.12 cm²/m²) were similar between men and women (all P≥0.18). Median aortic valve calcification (1973 [1124-3490] Agatston units) and mean valve weight (2.36±0.99 g) were lower in women compared with men (both P<0.0001). Aortic valve calcification density correlated better with valve weight in men (r²=0.57; P<0.0001) than in women (r²=0.26; P=0.0008). After adjustment for age, body mass index, aortic valve calcification density, and aortic annulus diameter, female sex was an independent risk factor for higher fibrosis score in AS valves (P=0.003). Picrosirius red staining of explanted valves showed greater amount of collagen fibers (P=0.01), and Masson trichrome staining revealed a greater proportion of dense connective tissue (P=0.02) in women compared with men.

CONCLUSIONS

In this series of patients with tricuspid aortic valve and similar AS severity, women have less valvular calcification but more fibrosis compared with men. These findings suggest that the pathophysiology of AS and thus potential targets for drug development may be different according to sex.

Pathological Investigation of Congenital Bicuspid Aortic Valve Stenosis, Compared with Atherosclerotic Tricuspid Aortic Valve Stenosis and Congenital Bicuspid Aortic Valve Regurgitation

Background

Congenital bicuspid aortic valve (CBAV) is the main cause of aortic stenosis (AS) in young adults. However, the histopathological features of AS in patients with CBAV have not been fully investigated.

Methods and Results

We examined specimens of aortic valve leaflets obtained from patients who had undergone aortic valve re/placement at our institution for severe AS with CBAV (n = 24, CBAV-AS group), severe AS with tricuspid aortic valve (n = 24, TAV-AS group), and severe aortic regurgitation (AR) with CBAV (n = 24, CBAV-AR group). We compared the histopathological features among the three groups. Pathological features were classified using semi-quantitative methods (graded on a scale 0 to 3) by experienced pathologists without knowledge of the patients’ backgrounds. The severity of inflammation, neovascularization, and calcium and cholesterol deposition did not differ between the CBAV-AS and TAV-AS groups, and these four parameters were less marked in the CBAV-AR group than in the CBAV-AS (all p<0.01). Meanwhile, the grade of valvular fibrosis was greater in the CBAV-AS group, compared with the TAV-AS and CBAV-AR groups (both p<0.01). In AS patients, thickness of fibrotic lesions was greater on the aortic side than on the ventricular side (both p<0.01). Meanwhile, thickness of fibrotic lesions was comparable between the aortic and ventricular sides in CBAV-AR patients (p = 0.35).

Conclusions

Valvular fibrosis, especially on the aortic side, was greater in patients with CBAV-AS than in those without, suggesting a difference in the pathogenesis of AS between CBAV and TAV.

The angiotensin II type 1 receptor blocker losartan attenuates bioprosthetic valve leaflet calcification in a rabbit intravascular implant model

OBJECTIVES

There is evidence that angiotensin II type I receptor blocker (ARB) could reduce structural valve deterioration. However, the anticalcification effect on the bioprosthetic heart valve (BHV) has not been investigated. Thus, we investigated the effects of losartan (an ARB) on calcification of implanted bovine pericardial tissue in a rabbit intravascular implant model.

METHODS

A total of 16 male New Zealand White rabbits (20 weeks old, 2.98-3.34 kg) were used in this study. Commercially available BHV leaflet of bovine pericardium was trimmed to the shape of a 3-mm triangle and implanted to both external jugular veins of the rabbit. The ARB group (n = 8) was given 25 mg/kg of powdered losartan daily until 6 weeks after surgery by direct administration in the buccal pouch of the animals. The control group (n = 8) was given 5 ml of normal saline by the same method. After 6 weeks, quantitative calcium determination, histological evaluation and western blot analysis of interleukin-6 (IL-6), osteopontin and bone morphogenetic protein 2 (BMP-2) were performed to investigate the mechanisms of the anticalcification effect of losartan.

RESULTS

No deaths or complications such as infection or haematoma were recorded during the experiment. All animals were euthanized on the planned date. The calcium measurement level in the ARB group (2.28 ± 0.65 mg/g) was significantly lower than that in the control group (3.68 ± 1.00 mg/g) (P = 0.0092). Immunohistochemistry analyses revealed that BMP-2-positive reactions were significantly attenuated in the ARB group. Western blot analysis showed that losartan suppressed the expression of IL-6, osteopontin and BMP-2.

CONCLUSIONS

Our results indicate that losartan significantly attenuates postimplant degenerative calcification of a bovine pericardial bioprosthesis in a rabbit intravascular implant model. Further studies are required to assess the effects of ARBs on BHV tissue in orthotopic implantations using a large animal model.

Fibrotic Aortic Valve Stenosis in Hypercholesterolemic/Hypertensive Mice

OBJECTIVE

Hypercholesterolemia and hypertension are associated with aortic valve stenosis (AVS) in humans. We have examined aortic valve function, structure, and gene expression in hypercholesterolemic/hypertensive mice.

APPROACH AND RESULTS

Control, hypertensive, hypercholesterolemic (Apoe(-/-)), and hypercholesterolemic/hypertensive mice were studied. Severe aortic stenosis (echocardiography) occurred only in hypercholesterolemic/hypertensive mice. There was minimal calcification of the aortic valve. Several structural changes were identified at the base of the valve. The intercusp raphe (or seam between leaflets) was longer in hypercholesterolemic/hypertensive mice than in other mice, and collagen fibers at the base of the leaflets were reoriented to form a mesh. In hypercholesterolemic/hypertensive mice, the cusps were asymmetrical, which may contribute to changes that produce AVS. RNA sequencing was used to identify molecular targets during the developmental phase of stenosis. Genes related to the structure of the valve were identified, which differentially expressed before fibrotic AVS developed. Both RNA and protein of a profibrotic molecule, plasminogen activator inhibitor 1, were increased greatly in hypercholesterolemic/hypertensive mice.

CONCLUSIONS

Hypercholesterolemic/hypertensive mice are the first model of fibrotic AVS. Hypercholesterolemic/hypertensive mice develop severe AVS in the absence of significant calcification, a feature that resembles AVS in children and some adults. Structural changes at the base of the valve leaflets include lengthening of the raphe, remodeling of collagen, and asymmetry of the leaflets. Genes were identified that may contribute to the development of fibrotic AVS.

Innate and Adaptive Immunity in Calcific Aortic Valve Disease

Calcific aortic valve disease (CAVD) is the most common heart valve disorder. CAVD is a chronic process characterized by a pathologic mineralization of valve leaflets. Ectopic mineralization of the aortic valve involves complex relationships with immunity. Studies have highlighted that both innate and adaptive immunity play a role in the development of CAVD. In this regard, accumulating evidence indicates that fibrocalcific remodelling of the aortic valve is associated with activation of the NF-κB pathway. The expression of TNF-α and IL-6 is increased in human mineralized aortic valves and promotes an osteogenic program as well as the mineralization of valve interstitial cells (VICs), the main cellular component of the aortic valve. Different factors, including oxidized lipid species, activate the innate immune response through the Toll-like receptors. Moreover, VICs express 5-lipoxygenase and therefore produce leukotrienes, which may amplify the inflammatory response in the aortic valve. More recently, studies have emphasized that an adaptive immune response is triggered during CAVD. Herein, we are reviewing the link between the immune response and the development of CAVD and we have tried, whenever possible, to keep a translational approach.

Circulating levels of matrix gla protein and progression of aortic stenosis: a substudy of the Aortic Stenosis Progression Observation: Measuring Effects of rosuvastatin (ASTRONOMER) trial

BACKGROUND

Matrix γ-carboxyglutamate protein is an inhibitor of cardiovascular calcification. The objective of this substudy of the Aortic Stenosis Progression Observation: Measuring Effects of Rosuvastatin (ASTRONOMER) trial was to examine the relationship between total (ie, carboxylated [active] form + uncarboxylated [inactive] form) circulating desphosphorylated matrix γ-carboxyglutamate protein (dpMGP) level and the progression rate of aortic stenosis (AS).

METHODS

Among the patients included in the ASTRONOMER trial, 215 patients had measures of baseline circulating total dpMGP level and an echocardiographic follow-up (mean follow-up: 3.5 ± 1.3 years). Progression of AS was assessed according to the measurement of the annualized increase in peak aortic jet velocity.

RESULTS

In the whole cohort, baseline dpMGP level was associated with faster progression rate of peak aortic jet velocity (r = 0.16; P = 0.02) in individual analysis but not in multivariable analysis (P = 0.40). However, there was a significant interaction (P = 0.03) between dpMGP level and age, with respect to the effect on AS progression. After dichotomization according to median value of age (ie, 57 years old), total dpMGP level was associated with faster AS progression rate (r = 0.24; P = 0.008) in the younger patients, and this association remained significant in multivariable analysis (P = 0.04), but not in the older ones. The independent correlates of dpMGP level were fasting glucose (P = 0.009) and oxidized low-density lipoprotein (P = 0.01).

CONCLUSIONS

This is the first prospective study to demonstrate a relationship between increased circulating levels of total dpMGP and faster progression rate of AS in younger individuals. Future studies are needed to determine if dpMGP is simply a marker or a contributing factor to ectopic mineralization of aortic valve.

Molecular biology of calcific aortic valve disease: towards new pharmacological therapies

Calcific aortic valve disease (CAVD) is a chronic process leading to fibrosis and mineralization of the aortic valve. Investigations in the last several years have emphasized that key underlying molecular processes are involved in the pathogenesis of CAVD. In this regard, the processing of lipids and their retention has been underlined as an important mechanism that triggers inflammation. In turn, inflammation promotes/enhances the mineralization of valve interstitial cells, the main cellular component of the aortic valve. On the other hand, transformation of valve interstitial cells into myofibroblasts and osteoblast-like cells is determined by several signaling pathways having reciprocal cross-talks. In addition, the mineralization of the aortic valve has been shown to rely on ectonucleotidase and purinergic signaling. In this review, the authors have highlighted key molecular underpinnings of CAVD that may have significant relevance for the development of novel pharmaceutical therapies.

Basic mechanisms of calcific aortic valve disease

Calcific aortic valve disease (CAVD) is the most common heart valve disorder. There is no medical treatment to prevent and/or promote the regression of CAVD. Hence, it is of foremost importance to delineate and understand the key basic underlying mechanisms involved in CAVD. In the past decade our comprehension of the underpinning processes leading to CAVD has expanded at a fast pace. Hence, our understanding of the basic pathobiological processes implicated in CAVD might lead eventually to the development of novel pharmaceutical therapies for CAVD. In this review, we discuss molecular processes that are implicated in fibrosis and mineralization of the aortic valve. Specifically, we address the role of lipid retention, inflammation, phosphate signalling and osteogenic transition in the development of CAVD. Interplays between these different processes and the key regulation pathways are discussed along with their clinical relevance.

P2Y2 receptor represses IL-6 expression by valve interstitial cells through Akt: implication for calcific aortic valve disease

Calcific aortic valve disease (CAVD) is a disorder characterized by an abnormal mineralization, which may have intricate links with inflammation. Interleukin-6 (IL-6) and its cognate cytokines are widely expressed and exert pleiotropic effects on different tissues. In this study, we examined the expression of the IL-6 family of cytokines in human CAVD by using a transcriptomic approach and we performed in-depth functional assays with valve interstitial cells (VICs) to unravel the process regulating IL-6 expression and its role during the mineralization of the aortic valve. We documented by both microarray and q-PCR analyses an elevated expression of IL-6 in human CAVD, which was correlated with the remodeling process. IL-6 was highly expressed by VICs. We found that following treatment with a phosphate-containing medium the level of IL-6 expressed by VICs increased by several-fold. Phosphate-induced expression of IL-6 relied on reduced PI3K/Akt signaling downstream of the P2Y2 receptor (P2Y2R). In this regard, we found by using transfection experiments that Akt-1 is a negative regulator of the NF-κB pathway. In addition, by using a siRNA targeting IL-6 we found that phosphate-induced mineralization was largely dependent on IL-6 expression. A transfection of Akt-1 rescued the hypermineralizing phenotype of P2Y2R(-/-) mouse VICS (MVICs). Hence, we documented a novel mechanism whereby P2Y2R and Akt modulate the NF-κB pathway and its downstream target IL-6, which is a strong promoter of the mineralization of VICs.