Sex differences in aortic valve calcification measured by multidetector computed tomography in aortic stenosis

Association of aortic valve size with the degree of aortic valve calcification in severe high-gradient aortic stenosis

AIMS

Less pronounced calcification of the aortic valve (AVC) was observed in women with aortic stenosis (AS) when compared with men. Since women have smaller aortic valves (AVs), this could explain a lower calcium load. We aimed to analyse the association of AV size with AVC independent from sex.

METHODS AND RESULTS

Consecutive patients with high-gradient AS, who underwent cardiac computed tomography (CT), were assessed. AV annulus area and AVC with the Agatston score were measured on CT. In total, 601 patients (mean age 80 ± 7 years, 45% female) were included. Women had smaller AV annulus areas (4.12 ± 0.67 vs. 5.15 ± 0.78 cm2, P < 0.001) and lower Agatston scores [2018 (1456-3017) vs. 3394 (2562-4530), P < 0.001] than men. We found a significant correlation (r = 0.594, P < 0.001) and independent association (β = 926.20, P < 0.001) of AV annulus area with AVC. On separate regression analyses for men and women, AVC was independently associated with AV annulus area in both sexes (βmen = 887.77; βwomen = 863.48, both P < 0.001). When patients were stratified into AV size quartiles, patients in the lower quartiles were more likely to have AVC values below recommended sex-specific AVC thresholds. In the lowest quartile, 28% of female and 27% of male patients had Agatston scores below 1200 Agatston units (AU) (women) and 2000 AU (men), while this proportion decreased to 6 and 2%, respectively, in the quartiles with the largest annulus areas.

CONCLUSION

In high-gradient AS, AVC strongly depends on AV annulus area. This association is not dependent on sex. Thus, AVC should be indexed to AV size in addition to sex.

A collagen-based laboratory model to mimic sex-specific features of calcific aortic valve disease

Calcific aortic valve disease (CAVD) shows in the deposition of calcium phosphates in the collagen-rich layer of the valve leaflets. This stiffens the leaflets and eventually leads to heart failure. Recent research suggests that CAVD follows sex-specific pathways: at the same severity of the disease, women tend to have fewer and less crystalline calcifications, and the phases of their calcifications are decidedly different than those of men; namely, dicalcium phosphate dihydrate (DCPD) - one of the mineral phases in CAVD - occurs almost exclusively in females. Furthermore, the morphologies of heart valve calcifications might be sex-specific, but the sex dependence of the morphologies has not been systematically investigated. Herein, we first show that male CAVD patients have more compact and less fibrous calcifications than females, establishing sex-dependent morphological features of heart valve calcification. We then build a model that recapitulates the sex differences of the calcifications in CAVD, which is based on a collagen gel that we calcify in simulated body fluid with varying fetuin A concentrations. With increasing fetuin A concentration, the calcifications become less crystalline and more fibrous, and more DCPD deposits in the collagen matrix, resembling the physicochemical characteristics of the calcifications in female valves. Lower fetuin A concentrations give rise to a model that replicates male-specific mineral characteristics. The models could be used to develop sex-specific detection and treatment methods for CAVD. STATEMENT OF SIGNIFICANCE: Although calcific aortic valve disease (CAVD) affects ∼10 million people globally, researchers have only discovered recently that the disease follows sex-specific pathways, and many of its sex-specific features remain unknown. To further our understanding of sex differences in CAVD and to develop better detection and treatment methods, there is an urgent need to establish models for CAVD that account for its sex-specific manifestations. In this study, we first show that CAVD calcifications in men and women take on different morphologies. Second, we present a model that can replicate physicochemical calcification characteristics of male or female valves, including morphology, and that can help to develop sex-specific detection and treatment methods for CAVD.

Calcific aortic stenosis: omics-based target discovery and therapy development

Calcific aortic valve disease (CAVD) resulting in aortic stenosis (AS) is the most common form of valvular heart disease, affecting 2% of those over age 65. Those who develop symptomatic severe AS have an average further lifespan of <2 years without valve replacement, and three-quarters of these patients will develop heart failure, undergo valve replacement, or die within 5 years. There are no approved pharmaceutical therapies for AS, due primarily to a limited understanding of the molecular mechanisms that direct CAVD progression in the complex haemodynamic environment. Here, advances in efforts to understand the pathogenesis of CAVD and to identify putative drug targets derived from recent multi-omics studies [including (epi)genomics, transcriptomics, proteomics, and metabolomics] of blood and valvular tissues are reviewed. The recent explosion of single-cell omics-based studies in CAVD and the pathobiological and potential drug discovery insights gained from the application of omics to this disease area are a primary focus. Lastly, the translation of knowledge gained in valvular pathobiology into clinical therapies is addressed, with a particular emphasis on treatment regimens that consider sex-specific, renal, and lipid-mediated contributors to CAVD, and ongoing Phase I/II/III trials aimed at the prevention/treatment of AS are described.

Trymethylamine-N-oxide, a gut-derived metabolite, induces myofibroblastic activation of valvular interstitial cells through endoplasmic reticulum stress

Calcific aortic valve disease currently lacks effective treatments beyond surgical valve replacement, due to an incomplete understanding of its pathogenesis. Emerging evidence suggests that the gut microbiome influences cardiovascular health through the production of metabolites derived from dietary components. Among them, trimethylamine-N-oxide (TMAO) has been identified as a potential causal factor for several cardiovascular conditions. However, its role in the development of aortic valve disease remains poorly understood. This study sought to investigate the impact of TMAO on valvular interstitial cells (VICs), the most abundant cell type in the aortic valve. Here, we demonstrate that TMAO activates VICs towards a myofibroblastic profibrotic phenotype. Using an in vitro protocol to generate quiescent VICs, we found that TMAO induces the upregulation of myofibroblastic markers in a sex-independent manner. These quiescent VICs were more sensitive to TMAO than conventionally cultured VICs. Treatment with TMAO also elevated extracellular matrix production and oxidative stress, phenotypic hallmarks of an activated profibrotic state. Finally, inhibition of the endoplasmic reticulum stress kinase prior to TMAO treatment blocked all effects of this metabolite. These findings suggest that TMAO contributes to the early stages of valve disease by promoting VIC activation through endoplasmic reticulum stress mechanisms. Understanding the role of TMAO and other gut-derived metabolites in the pathogenesis of valve disease could inform the development of novel preventive or therapeutic strategies to modify or delay disease progression. Furthermore, these insights underscore the importance of host-microbiome interactions and highlight the potential for targeted dietary interventions to mitigate cardiovascular disease risk.

Current Status of CT Imaging Before Common Transcatheter Interventions for Structural Heart Disease

Background: Over the past decade, several trials and observational studies have validated the use of minimally invasive cardiac interventions as viable treatment options for various cardiac diseases. Transcatheter techniques for severe aortic valve stenosis have rapidly emerged as alternatives to surgical aortic valve replacement in certain patient populations. Additionally, non-surgical treatment options have expanded for conditions affecting other cardiac valves, such as the mitral valve. These emerging minimally invasive interventions complement already well-established endovascular techniques for, among others, atrial septal defect closure, left atrial appendage occlusion and pulmonary vein isolation in patients with atrial fibrillation. Given their non-surgical nature and lack of direct visualisation of the targeted anatomy, these procedures heavily rely on precise pre-procedural radiological imaging for optimal patient selection and procedural success. Method: This paper is based on the expert opinion of the authors and an exhaustive literature research. Results: This manuscript reviews the most commonly employed minimally invasive cardiac interventions, highlighting the essential pre-procedural imaging information and key aspects that must be included in radiological reports to mitigate potential complications. Conclusion: Accurate pre-procedural imaging is crucial for ensuring safe and effective minimally invasive cardiac interventions, underscoring the importance of the radiologist in the pre-procedural work-up of these patients.

Usefulness of Aortic Valve Calcification in Patients With Low-Flow Aortic Stenosis

BACKGROUND

Aortic valve calcification (AVC) has been shown to be a powerful assessment of aortic stenosis (AS) severity and a predictor of adverse outcomes. However, its accuracy in patients with low-flow AS has not yet been proven. The objective of the study was to assess the predictive value of AVC in patients with classical low-flow (CLF, that is, low-flow reduced left ventricular ejection fraction) or paradoxical low-flow (PLF, that is, low-flow preserved left ventricular ejection fraction) AS.

METHODS

We prospectively included 641 patients, 319 (49.8%) with CLF-AS and 322 (50.2%) with PLF-AS, who underwent Doppler echocardiography and multidetector computed tomography. AVC ratio (AVCratio) was calculated as AVC divided by the sex-specific AVC threshold for AS severity; AVC score ≥2000 Agatston units in male patients and ≥1200 Agatston units in female patients. The primary end point of the study was all-cause mortality regardless of treatment.

RESULTS

Sex-specific AVC thresholds identified AS severity correctly in 137 (87%) of the patients. During a median follow-up of 4.9 (4.3-5.9) years, there were 265 deaths. After comprehensive adjustment, AVCratio was associated with all-cause mortality in patients with CLF-AS (adjusted hazard ratio, 1.25 [95% CI, 1.01-1.56]; P=0.046) and PLF-AS (adjusted hazard ratio, 1.51 [95% CI, 1.14-2.00]; P=0.004). There was an interaction (P=0.001) between AVC and AS flow patterns (ie, CLF versus PLF) with regard to the prediction of mortality. The best AVCratio threshold to predict mortality was different in patients with CLF-AS (AVCratio ≥0.7) and PLF-AS (AVCratio ≥1). After a comprehensive analysis, AVCratio as a dichotomic variable was associated with all-cause mortality in all groups (P≤0.001). The addition of AVCratio to the models improved all models' predictive value (all net reclassification index >18%; all P≤0.05).

CONCLUSIONS

In patients with CLF-AS or PLF-AS, AVC is a major predictor of mortality. Thus, AVC should be used in low-flow patients to assess AS severity and stratify risk. Importantly, in patients with reduced left ventricular ejection fraction, a nonsevere AS (ie, AVC 70% of severe) could be associated with reduced survival.

Very severe aortic valve stenosis: Diagnostic value of computed tomography aortic valve calcium scoring

BACKGROUND

(A) Very severe aortic valve stenosis (VSAS; Vmax ≥ 5 ​m/s, MPG ≥60 ​mmHg) is a critical condition with unfavorable clinical outcomes. Guidelines regard VSAS as one criterion for considering valve replacement in asymptomatic patients. (B) Guidelines recommend the use of aortic valve calcium (AVC) scoring as a parameter to differentiate between moderate and severe aortic valve stenosis (SAS). The aim of our study is to propose AVC thresholds for the discrimination between SAS and VSAS.

METHODS

Data of patients from a single center who underwent transcatheter aortic valve implantation (n ​= ​523) were retrospectively analyzed. Patients with concordant AS (n ​= ​430) were divided into SAS (n ​= ​344) and VSAS (n ​= ​86) groups and compared in terms of absolute AVC and indexed AVC (body surface area; aortic valve annulus area).

RESULTS

Mean AVC was significantly higher in men (m) than in women (w), and significantly higher in VSAS than in SAS (m: SAS 3572.0 AU; VSAS 5465.0 AU; w: SAS 2252.5 AU; VSAS 3064.5 AU; all p ​< ​0,001). ROC curve analyses showed AVC to be a predictor of VSAS in both sexes (m: AUC 0.794; p ​< ​0.001; w: AUC 0.725; p ​< ​0.001), with optimal cut-off values of 3706.5 AU (m) and 2374.5 (w). Some indexed AVC had a slightly, but not relevantly, better predictive value.

CONCLUSION

The proposed AVC thresholds - approximately 3700 AU (m) and 2400 AU (w) - showed significant predictive power to differentiate SAS from VSAS in the study cohort.

Aortic Stenosis, Heart Failure, and Aortic Valve Replacement

Importance

Heart failure (HF) and aortic stenosis (AS) frequently coexist, presenting a complex clinical challenge due to their intertwined pathophysiology and associated high morbidity and mortality. Despite numerous advancements in transcatheter and surgical aortic valve replacement (AVR), HF decompensation remains the leading cause of cardiac rehospitalization and a major predictor of mortality in patients with AS, before or after AVR. This review aims to provide a comprehensive analysis of the interplay between AS and HF, delving into myocardial changes caused by stenotic insult, the impact of AVR on these changes, and the prevalence and contributing elements of HF before and after AVR.

Observations

The prevalence of HF remains high before and after AVR, particularly among patients with left ventricular dysfunction. Increased afterload from AS causes cardiac remodeling, which is initially benign but over time these changes become maladaptive, contributing to HF and increased mortality. The progression of HF is influenced by the degree of reverse cardiac remodeling, which can be affected by comorbid conditions, the hemodynamic performance of the valve prosthesis, and vascular stiffness. Several blood and imaging biomarkers offer insights into underlying AS pathophysiology, serving as mortality predictors and predicting HF in this patient population.

Conclusions and Relevance

HF development in AS is multifactorial and its link to left ventricular dysfunction is a complex process. Delineating the determinants of HF admissions in AS is crucial for identifying individuals at high risk. Identifying the early signs of left ventricular decompensation by using surrogate markers may be the key, even before left ventricular function becomes impaired. Translating multimodality imaging techniques and biomarkers into routine clinical practice for evaluating cardiac damage and integrating these markers with patient and procedural factors that affect HF before and after AVR can facilitate timely intervention, minimizing the likelihood of HF progression and influencing future guidelines.

Dobutamine Stress Echocardiography in Low-Gradient Aortic Stenosis

IMPORTANCE

Guidelines recommend the use of dobutamine stress echocardiography (DSE) in patients with low-gradient aortic stenosis (AS) and left ventricular ejection fraction (LVEF) <50%. However, a paucity of DSE data exists when LVEF >35%.

OBJECTIVE

To examine the diagnostic accuracy of DSE in patients with low-gradient AS with a wide range of LVEF and to examine the interaction between the diagnostic accuracy of DSE and LVEF.

DESIGN, SETTING, AND PARTICIPANTS

Patients with mean gradient <40 mm Hg, aortic valve area <1.0 cm2, and stroke volume index ≤35 mL/m2 undergoing DSE and cardiac computer tomography (C-CT) were identified from 3 prospectively collected patient cohorts and stratified according to LVEF: LVEF<35%, LVEF 35% to 50%, and LVEF>50%.

EXPOSURE

Dobutamine stress echocardiography and C-CT were performed on patients with low-gradient AS.

MAIN OUTCOMES AND MEASURES

Severe AS was defined as aortic valve calcification score ≥2,000 arbitrary units (AU) among men and ≥1,200 AU for women on C-CT.

RESULTS

Of 221 patients included in the study, 78 (35%) presented with LVEF <35%, 67 (30%) with LVEF 35% to 50%, and 76 (34%) with LVEF >50%. Mean-gradient and aortic valve peak velocity during DSE showed significant diagnostic heterogeneity between LVEF groups, being most precise when LVEF <35% (both areas under the curve [AUC] = 0.90), albeit with optimal thresholds of 30 mm Hg and 377 cm/sec and a limited diagnostic yield in patients with LVEF ≥35% (AUC = 0.67 and 0.66 in LVEF 35% to 50% and AUC = 0.65 and 0.60 in LVEF ≥50%). Using guideline thresholds led to a sensitivity/specificity of 49%/84% for all patients with LVEF <50%.

CONCLUSION AND RELEVANCE

While DSE is safe and leads to an increase in stroke volume in patients with low-gradient AS regardless of LVEF, the association between DSE gradients and AS severity assessed by C-CT demonstrates important heterogeneity depending on LVEF, with the highest accuracy in patients with LVEF <35%.

Higher serum phosphate within the normal range is associated with the development of calcified aortic valve disease

Background

Despite the essential role of ectopic osteogenic calcium-phosphate metabolism in the development of calcific aortic valve disease (CAVD), the implications of high serum phosphate levels in CAVD development are not fully understood.

Methods

Asymptomatic individuals who underwent health screening using serial cardiac computed tomography (CT) and echocardiography were selected from a multicenter registry. CAVD was identified and quantified on CT images using the aortic valve calcification (AVC) score. The associations between initial serum phosphate levels and the presence of baseline CAVD, development of new CAVD, and the AVC score progression rate were investigated using multivariable regression models.

Results

A total of 736 individuals were selected for analysis, and the median interscan duration was 36.4 months. On initial CT, 83 (13.7%) participants had baseline CAVD, while 52 (7.0%) individuals developed new CAVD during follow-up. Serum phosphate levels were not associated with a higher probability of baseline CAVD but were predictive of newly developed CAVD (odds ratio per 1 mg/dl, 1.05; 95% confidence interval, 1.01-1.10; p = 0.02). Higher phosphate levels were also associated with a faster AVC score progression in those with baseline CAVD (regression coefficient per 1 mg/dl, 15.55 Agatston units/year; 95% confidence interval, 6.02-25.07; p < 0.01), an association which remained significant when the analysis was extended to include newly developed CAVD.

Conclusion

Even slight elevations in serum phosphate are associated with accelerated CAVD progression from an early stage. Further studies are needed to investigate whether the regulation of phosphate metabolism can slow the progression of CAVD to aortic stenosis.

Molecular Features of Calcific Aortic Stenosis in Female and Male Patients

Over the past 15 years, sex-related differences in aortic valve (AV) stenosis (AS) have been highlighted, affecting various aspects of AS, such as the pathophysiology, AV lesions, left ventricle remodelling, and outcomes. Female patients were found to present a more profibrotic pattern of leaflet remodelling and/or thickening, whereas male patients have a preponderance of calcification within stenosed leaflets. The understanding of these sex differences is still limited, owing to the underrepresentation of female patients in many basic and clinical research studies and trials. A better understanding of sex differences in the pathophysiology of AS may highlight new therapeutic targets that potentially could be sex-specific. This review aims to summarize sex-related differences in AS, as discovered from basic research experiments, covering aspects of the disease ranging from leaflet composition to signalling pathways, sex hormones, genetics and/or transcriptomics, and potential sex-adapted medical treatments.

Disproportionately high aortic valve calcium scores in atrial fibrillation: implications for transcatheter aortic valve replacement

AIMS

Doppler mean gradient (MG) can underestimate aortic stenosis (AS) severity in patients with atrial fibrillation (AF) compared with patients with sinus rhythm (SR), potentially delaying intervention in AF. This study compared outcomes in patients with AF and SR following transcatheter aortic valve replacement (TAVR) and investigated delay in TAVR based on computed tomography aortic valve calcium score (AVCS).

METHODS AND RESULTS

Patients who underwent TAVR from 2013 to 2017 for native valve severe AS were identified from an institutional database. Baseline characteristics and overall survival were compared between those with SR and AF. There were 820 patients (mean age 81 years; 41.6% females) included in this study. AF was present in 356 patients. Patients with AF were older (82.2 vs. 80.5, P = 0.003) and had a lower MG compared with patients with SR (42.0 vs. 44.9, P = 0.002) with similar indexed aortic valve area (0.4 vs. 0.4, P = 0.17). Median AVCS was higher in AF (males: AF 2850.0 vs. SR 2561.0, P = 0.044; females: AF 1942.0 vs. SR 1610.5, P = 0.025). Projected AVCS, assuming the same age of diagnosis, was similar between AF and SR. Median survival post-TAVR was worse in AF compared with SR (3.2 vs. 5.4 years, log rank P < 0.001). AF, lower MG, higher right ventricular systolic pressure, dialysis, diabetes, and significant tricuspid regurgitation were associated with higher mortality (P < 0.05 for all).

CONCLUSION

Older age and higher AVCS in patients with AF compared with those with SR suggest that AS was both underestimated and more advanced at TAVR referral.

Aortic balloon valvuloplasty outcome according to calcium distribution and valve geometry - The ABCD study

BACKGROUND

There is little data on the outcome of balloon aortic valvuloplasty (BAV) in relation to valve dimensions and calcification patterns. The procedure is not standardized, particularly the choice of balloon size.

METHODS

This retrospective multicenter study focused on BAV efficacy and safety by analyzing the relationship between balloon size, annulus geometry (i.e., diameters, perimeter, and area), and calcification patterns (total burden and calcium distribution over each individual leaflet). From March 2018 to March 2023, all consecutive patients who underwent clinically indicated BAV and ECG-gated multidetector computed tomography of the aorta were included, except those with a bicuspid valve. Calcium score was calculated on contrast-enhanced images based on a luminal attenuation threshold of +100 HU.

RESULTS

One hundred and fifteen patients were included. Procedural success was 82.6 %. The balloon-to-annulus ratio (BAR) relative to diameter, perimeter, and area was higher in patients with successful BAV. Patients with unsuccessful BAV had a significantly higher aortic valve calcium burden. The complication rate was 4.3 % and there was no association with valve geometry or calcium burden. A trend towards a reduced complication rate was found as calcium asymmetry increased. BAR minimum annulus diameter was the best parameter in predicting procedural success, with a cut-off at 0.85.

CONCLUSIONS

BAV efficacy is correlated directly with balloon size in relation to annulus dimension and inversely with total calcium burden. The minimum diameter of the valve may be adopted as a reference for balloon sizing.

Grading of Aortic Valve Calcification Severity and Risk Stratification in Aortic Stenosis

BACKGROUND

Thresholds of aortic valve calcification (AVC) to define hemodynamically moderate aortic stenosis (AS) from mild are lacking. We aimed to establish a novel grading classification of AVC as quantified by computed tomography and determine its prognostic value.

METHODS AND RESULTS

This study included 915 patients with at least mild AS (mean age 70±12 years, 30% women) from a multicenter prospective registry. All patients underwent Doppler-echocardiography and noncontrast computed tomography within 3 months. Primary end point was the occurrence of all-cause death. Receiver operating characteristic curves analyses were used to determine the sensitivity and specificity of sex-specific thresholds of AVC to identify hemodynamically moderate AS. Optimal thresholds (ie, with best sensitivity/specificity) of AVC to distinguish moderate (aortic valve area 1.0-1.5 cm2 and mean gradient 20-39 mm Hg) from mild AS (aortic valve area >1.5 cm2 and mean gradient <20 mm Hg) were AVC ≥360 arbitrary units in women and ≥1037 arbitrary units in men. Based on the guidelines' thresholds for severe AS and the new thresholds in our study for moderate AS, 312 (34%) patients had mild, 253 (28%) moderate, and 350 (38%) severe AVC. During a mean follow-up of 5.6±3.9 years, 183 (27%) deaths occurred. In Cox multivariable models, AVC remained associated with an increased risk of death (adjusted hazard ratio per grade increase, 1.94 [95% CI, 1.53-2.56]; P<0.001).

CONCLUSIONS

A novel grading classification of anatomic AS severity based on sex-specific thresholds of AVC provides significant prognostic value for predicting mortality. These findings support the complementarity of computed tomography-calcium scoring to Doppler-echocardiography to corroborate AS severity and enhance risk stratification in patients with AS.

Normal-Flow Low-Gradient Aortic Stenosis: Comparing the U.S. and European Guidelines

Patients with normal-flow low-gradient (NFLG) severe aortic stenosis present both diagnostic and management challenges, with debate about the whether this represents true severe stenosis and the need for valve replacement. Studies exploring the natural history without intervention have shown similar outcomes of patients with NFLG severe aortic stenosis to those with moderate aortic stenosis and better outcomes after valve replacement than those with low-flow low-gradient severe aortic stenosis. Most studies (all observational) have shown that aortic valve replacement was associated with a survival benefit vs surveillance. Based on available data, the European Society of Cardiology/European Association for Cardio-Thoracic Surgery guidelines and European Association of Cardiovascular Imaging/American Society of Echocardiography suggest that these patients are more likely to have moderate aortic stenosis. This clinical entity is not mentioned in the American Heart Association/American College of Cardiology guidelines. Here we review the definition of NFLG severe aortic stenosis, potential diagnostic algorithms and points of error, the data supporting different management strategies, and the differing guidelines and outline the unanswered questions in the diagnosis and management of these challenging patients.

Th1 cells reduce the osteoblast-like phenotype in valvular interstitial cells by inhibiting NLRP3 inflammasome activation in macrophages

BACKGROUND AND AIMS

Inflammation is initiates the propagation phase of aortic valve calcification. The activation of NLRP3 signaling in macrophages plays a crucial role in the progression of calcific aortic valve stenosis (CAVS). IFN-γ regulates NLRP3 activity in macrophages. This study aimed to explore the mechanism of IFN-γ regulation and its impact on CAVS progression and valve interstitial cell transdifferentiation.

METHODS AND RESULTS

The number of Th1 cells and the expression of IFN-γ and STAT1 in the aortic valve, spleen and peripheral blood increased significantly as CAVS progressed. To explore the mechanisms underlying the roles of Th1 cells and IFN-γ, we treated CAVS mice with IFN-γ-AAV9 or an anti-IFN-γ neutralizing antibody. While IFN-γ promoted aortic valve calcification and dysfunction, it significantly decreased NLRP3 signaling in splenic macrophages and Ly6C+ monocytes. In vitro coculture showed that Th1 cells inhibited NLPR3 activation in ox-LDL-treated macrophages through the IFN-γR1/IFN-γR2-STAT1 pathway. Compared with untreated medium, conditioned medium from Th1-treated bone marrow-derived macrophages reduced the osteogenic calcification of valvular interstitial cells.

CONCLUSION

Inhibition of the NLRP3 inflammasome by Th1 cells protects against valvular interstitial cell calcification as a negative feedback mechanism of adaptive immunity toward innate immunity. This study provides a precision medicine strategy for CAVS based on the targeting of anti-inflammatory mechanisms.

Sex Differences in Aortic Stenosis: From the Pathophysiology to the Intervention, Current Challenges, and Future Perspectives

Calcific aortic stenosis (AS) is a major cause of morbidity and mortality in high-income countries. AS presents sex-specific features impacting pathophysiology, outcomes, and management strategies. In women, AS often manifests with a high valvular fibrotic burden, small valvular annuli, concentric left ventricular (LV) remodeling/hypertrophy, and, frequently, supernormal LV ejection fraction coupled with diastolic dysfunction. Paradoxical low-flow low-gradient AS epitomizes these traits, posing significant challenges post-aortic valve replacement due to limited positive remodeling and significant risk of patient-prosthesis mismatch. Conversely, men present more commonly with LV dilatation and dysfunction, indicating the phenotype of classical low-flow low-gradient AS, i.e., with decreased LV ejection fraction. However, these distinctions have not been fully incorporated into guidelines for AS management. The only treatment for AS is aortic valve replacement; women are frequently referred late, leading to increased heart damage caused by AS. Therefore, it is important to reassess surgical planning and timing to minimize irreversible cardiac damage in women. The integrity and the consideration of sex differences in the management of AS is critical. Further research, including sufficient representation of women, is needed to investigate these differences and to develop individualized, sex-specific management strategies.

Investigating the Impact of a Gut metabolite on Valvular Interstitial Cell Activation

Calcified Aortic Valve Disease (CAVD) affects up to 13% of the U.S. population and is linked to diet-induced changes in metabolism. Recent studies suggest that the gut metabolite trimethyl amine oxide (TMAO) may be a biomarker for atherosclerosis. Given the shared risk factors between atherosclerosis and CAVD, we hypothesize that TMAO may contribute to CAVD by activating the primary cell type in the valve, valve interstitial cells (VIC). VICs are usually found in a quiescent phenotype in healthy valves; however, VICs isolated from porcine aortic valves exhibit spontaneous activation in traditional culture. Thus, to study VIC activation induced by exposure to TMAO, we first applied our lab-engineered protocol to generate quiescent VICs (qVICs). TMAO treatment led to qVIC activation, demonstrated by increased αSMA expression, proliferation, and angiogenic cytokine secretion after 3 days in culture. The response to TMAO was not sex-specific with both male and female VICs responding to treatment with this metabolite. These results demonstrate that TMAO, a gut microbiome-derived metabolite, promotes the activation of quiescent VICs toward a myofibroblastic phenotype in vitro, potentially contributing to the initiation of CAVD. Overall, these findings underscore the significance of host-microbe interactions in the progression of cardiovascular disease.

Severe aortic stenosis: secular trends of incidence and outcomes

BACKGROUND AND AIMS

Severe aortic stenosis (AS) is the guideline-based indication for aortic valve replacement (AVR), which has markedly increased with transcatheter approaches, suggesting possible increasing AS incidence. However, reported secular trends of AS incidence remain contradictory and lack quantitative Doppler echocardiographic ascertainment.

METHODS

All adults residents in Olmsted County (MN, USA) diagnosed over 20 years (1997-2016) with incident severe AS (first diagnosis) based on quantitatively defined measures (aortic valve area ≤ 1 cm2, aortic valve area index ≤ 0.6 cm2/m2, mean gradient ≥ 40 mmHg, peak velocity ≥ 4 m/s, Doppler velocity index ≤ 0.25) were counted to define trends in incidence, presentation, treatment, and outcome.

RESULTS

Incident severe AS was diagnosed in 1069 community residents. The incidence rate was 52.5 [49.4-55.8] per 100 000 patient-year, slightly higher in males vs. females and was almost unchanged after age and sex adjustment for the US population 53.8 [50.6-57.0] per 100 000 residents/year. Over 20 years, severe AS incidence remained stable (P = .2) but absolute burden of incident cases markedly increased (P = .0004) due to population growth. Incidence trend differed by sex, stable in men (incidence rate ratio 0.99, P = .7) but declining in women (incidence rate ratio 0.93, P = .02). Over the study, AS clinical characteristics remained remarkably stable and AVR performance grew and was more prompt (from 1.3 [0.1-3.3] years in 1997-2000 to 0.5 [0.2-2.1] years in 2013-16, P = .001) but undertreatment remained prominent (>40%). Early AVR was associated with survival benefit (adjusted hazard ratio 0.55 [0.42-0.71], P < .0001). Despite these improvements, overall mortality (3-month 8% and 3-year 36%), was swift, considerable and unabated (all P ≥ .4) throughout the study.

CONCLUSIONS

Over 20 years, the population incidence of severe AS remained stable with increased absolute case burden related to population growth. Despite stable severe AS presentation, AVR performance grew notably, but while declining, undertreatment remained substantial and disease lethality did not yet decline. These population-based findings have important implications for improving AS management pathways.

Cardiovascular multimodality imaging in women: a scientific statement of the European Association of Cardiovascular Imaging of the European Society of Cardiology

Cardiovascular diseases (CVD) represent an important cause of mortality and morbidity in women. It is now recognized that there are sex differences regarding the prevalence and the clinical significance of the traditional cardiovascular (CV) risk factors as well as the pathology underlying a range of CVDs. Unfortunately, women have been under-represented in most CVD imaging studies and trials regarding diagnosis, prognosis, and therapeutics. There is therefore a clear need for further investigation of how CVD affects women along their life span. Multimodality CV imaging plays a key role in the diagnosis of CVD in women as well as in prognosis, decision-making, and monitoring of therapeutics and interventions. However, multimodality imaging in women requires specific consideration given the differences in CVD between the sexes. These differences relate to physiological changes that only women experience (e.g. pregnancy and menopause) as well as variation in the underlying pathophysiology of CVD and also differences in the prevalence of certain conditions such as connective tissue disorders, Takotsubo, and spontaneous coronary artery dissection, which are all more common in women. This scientific statement on CV multimodality in women, an initiative of the European Association of Cardiovascular Imaging of the European Society of Cardiology, reviews the role of multimodality CV imaging in the diagnosis, management, and risk stratification of CVD, as well as highlights important gaps in our knowledge that require further investigation.

Virtual non-iodine photon-counting CT-angiography for aortic valve calcification scoring

Photon-counting detector (PCD)-CT allows for reconstruction of virtual non-iodine (VNI) images from contrast-enhanced datasets. This study assesses the diagnostic performance of aortic valve calcification scoring (AVCS) derived from VNI datasets generated with a 1st generation clinical dual-source PCD-CT. AVCS was evaluated in 123 patients (statistical analysis only comprising patients with aortic valve calcifications [n = 56; 63.2 ± 11.6 years]), who underwent contrast enhanced electrocardiogram-gated (either prospective or retrospective or both) cardiac CT on a clinical PCD system. Patient data was reconstructed at 70 keV employing a VNI reconstruction algorithm. True non-contrast (TNC) scans at 70 keV without quantum iterative reconstruction served as reference in all individuals. Subgroup analysis was performed in 17 patients who received both, prospectively and retrospectively gated contrast enhanced scans (n = 8 with aortic valve calcifications). VNI images with prospective/retrospective gating had an overall sensitivity of 69.2%/56.0%, specificity of 100%/100%, accuracy of 85.4%/81.0%, positive predictive value of 100%/100%, and a negative predictive value of 78.2%/75.0%. VNI images with retrospective gating achieved similar results. For both gating approaches, AVCSVNI showed high correlation (r = 0.983, P < 0.001 for prospective; r = 0.986, P < 0.001 for retrospective) with AVCSTNC. Subgroup analyses demonstrated excellent intra-individual correlation between different acquisition modes (r = 0.986, P < 0.001). Thus, VNI images derived from cardiac PCD-CT allow for excellent diagnostic performance in the assessment of AVCS, suggesting potential for the omission of true non-contrast scans in the clinical workup of patients with aortic calcifications.

The Canadian Women's Heart Health Alliance ATLAS on the Epidemiology, Diagnosis, and Management of Cardiovascular Disease in Women - Chapter 8: Knowledge Gaps and Status of Existing Research Programs in Canada

Despite significant progress in medical research and public health efforts, gaps in knowledge of women's heart health remain across epidemiology, presentation, management, outcomes, education, research, and publications. Historically, heart disease was viewed primarily as a condition in men and male individuals, leading to limited understanding of the unique risks and symptoms that women experience. These knowledge gaps are particularly problematic because globally heart disease is the leading cause of death for women. Until recently, sex and gender have not been addressed in cardiovascular research, including in preclinical and clinical research. Recruitment was often limited to male participants and individuals identifying as men, and data analysis according to sex or gender was not conducted, leading to a lack of data on how treatments and interventions might affect female patients and individuals who identify as women differently. This lack of data has led to suboptimal treatment and limitations in our understanding of the underlying mechanisms of heart disease in women, and is directly related to limited awareness and knowledge gaps in professional training and public education. Women are often unaware of their risk factors for heart disease or symptoms they might experience, leading to delays in diagnosis and treatments. Additionally, health care providers might not receive adequate training to diagnose and treat heart disease in women, leading to misdiagnosis or undertreatment. Addressing these knowledge gaps requires a multipronged approach, including education and policy change, built on evidence-based research. In this chapter we review the current state of existing cardiovascular research in Canada with a specific focus on women.

Aortic Valve Calcium Score by Computed Tomography as an Adjunct to Echocardiographic Assessment-A Review of Clinical Utility and Applications

Aortic valve stenosis (AS) is increasing in prevalence due to the aging population, and severe AS is associated with significant morbidity and mortality. Echocardiography remains the mainstay for the initial detection and diagnosis of AS, as well as for grading of severity. However, there are important subgroups of patients, for example, patients with low-flow low-gradient or paradoxical low-gradient AS, where quantification of severity of AS is challenging by echocardiography and underestimation of severity may delay appropriate management and impart a worse prognosis. Aortic valve calcium score by computed tomography has emerged as a useful clinical diagnostic test that is complimentary to echocardiography, particularly in cases where there may be conflicting data or clinical uncertainty about the degree of AS. In these situations, aortic valve calcium scoring may help re-stratify grading of severity and, therefore, further direct clinical management. This review presents the evolution of aortic valve calcium score by computed tomography, its diagnostic and prognostic value, as well as its utility in clinical care.

Association of Age and Sex With Use of Transcatheter Aortic Valve Replacement in France

BACKGROUND

Current guidelines recommend selecting surgical aortic valve replacement (SAVR) or transcatheter aortic valve replacement (TAVR) based on age, comorbidities, and surgical risk. Nevertheless, reports from the United States suggest a rapid expansion of TAVR in young patients.

OBJECTIVES

The authors sought to evaluate the trends in TAVR uptake at a nationwide level in France according to age and sex.

METHODS

Using a nationwide administrative database, we evaluated age- and sex-related trends in TAVR uptake, patient demographics, and in-hospital outcomes between 2015 and 2020.

RESULTS

A total of 107,397 patients (44.0% female) underwent an isolated aortic valve replacement (AVR) (59.1% TAVR, 40.9% SAVR). In patients <65 years of age, the proportion of TAVR increased by 63.2% (P < 0.001) from 2015 to 2020 but remained uncommon at 11.1% of all AVR by 2020 (12.4% in females, 10.6% in males) while TAVR was the dominant modality in patients ≥65 years of age. In patients undergoing TAVR, the Charlson comorbidity index (CCI) (P = 0.119 for trend) and in-hospital mortality (P = 0.740 for trend) remained unchanged in patients <65 years of age but declined in those ≥65 years of age irrespective of sex (all P < 0.001 for trends). Females were older (P < 0.001), had lower CCI (P < 0.001), were more likely to undergo TAVR (P < 0.001), and experienced higher in-hospital mortality (TAVR, P = 0.015; SAVR, P < 0.001) that persisted despite adjustment for age and CCI.

CONCLUSIONS

In France, the use of TAVR remained uncommon in young patients, predominantly restricted to those at high risk. Important sex differences were observed in patent demographics, selection of AVR modality, and patient outcomes. Additional research evaluating the long-term impact of TAVR use in young patients and prospective data evaluating sex differences in AVR modality selection and outcomes are needed.

Sex Differences in Clinical Outcomes after Aortic Valve Intervention for Isolated Severe Aortic Stenosis

There are known pathophysiologic and clinical differences according to sex in patients with aortic stenosis (AS). To evaluate if these differences persist after valve replacement, we conducted an observational study including 451 patients with symptomatic AS who survived aortic valve intervention (AVI) in two centers. Clinical data and mortality were evaluated at a mean follow-up of 5 years. 56% of patients were women. At baseline, women were older (80.6 vs. 78 years, p = 0.013), presented higher mean gradient (48 vs. 45 mmHg, p = 0.023), lower aortic valve area (0.70 vs. 0.74 cm2, p = 0.002) and higher systolic pulmonary artery pressure (36 vs. 33 mmHg, p = 0.016). They underwent percutaneous aortic valve replacement more frequently than men (47 vs. 35.9%, p = 0.017). At 5 years follow-up, women required more admissions due to heart failure (23 vs. 9%, p = 0.046) but they did not present higher cardiovascular nor overall mortality (27.7% vs. 29.8%, p = 0.741; 11.1 vs. 10.1%, p = 0.619, respectively). Female sex was an independent predictor of heart failure hospitalization at follow-up (HR 95% 1.16-4.22, p = 0.016). Women undergo AVI at a more advanced stage than men, resulting in a higher frequency of readmissions due to heart failure during the follow-up period, but not in higher mortality.

Calcium Scoring to Classify Aortic Valve Stenosis Severity: What Is the Current Data?

PURPOSE OF REVIEW

This review explores current clinical value of aortic valve calcification (AVC) in classifying aortic valve stenosis (AS) severity, refining patient's follow-up, as well as novel and potential applications of this highly accurate marker in improving outcomes for AS patients. AVC limitations and important particularities regarding sex, valve phenotype, and ethnicity will also be addressed.

RECENT FINDINGS

Sex-specific AVC cut-offs have been included in current guidelines to identify severe AS when echocardiography is inconclusive. AVC is also associated with AS progression and could help refine the timing for patient's follow-up. In patients with AS, Doppler echocardiography is the gold standard for the assessment of AS severity. However, in more than one-third of patients, echocardiographic parameters are discordant, casting shadow on the true severity of the disease. Considering active leaflet calcification is the driving mechanism of AS, quantification of AVC has been shown to be of great interest for distinguishing true-severe from pseudo-severe AS. Moreover, AVC is closely associated with AS progression and outcomes.

Alerting trends in epidemiology for calcific aortic valve disease, 1990-2019: An age-period-cohort analysis for the Global Burden of Disease Study 2019

AIMS

To assess the trends in calcific aortic valve disease (CAVD) epidemiology, with an emphasis on CAVD mortality, leading risk factors, and their associations with age, period, and birth cohort.

METHODS AND RESULTS

Prevalence, disability-adjusted life years, and mortality were derived from the Global Burden of Disease Study 2019. The age-period-cohort model was employed to study the detailed trends of CAVD mortality and its leading risk factors. Globally, CAVD showed unsatisfactory results from 1990 to 2019, with the CAVD deaths of 127 000 in 2019. CAVD mortality was substantially reduced in high socio-demographic index (SDI) countries [-1.45%, 95% confidence interval (CI) (-1.61 to -1.30)], mildly increased in high-middle SDI countries [0.22%, 95% CI (0.06-0.37)], and unchanged in other SDI quintiles. There was a noticeable transition in CAVD deaths from younger to older populations globally. The CAVD mortality increased exponentially with age, and the male had higher mortality than the female before 80 years old. Favourable period [0.69, 95% CI (0.66-0.72)] and birth effects [0.30, 95% CI (0.22-0.43)] were mainly observed in high SDI countries, while unfavourable effects were mostly noticed in high-middle SDI countries. High systolic blood pressure was the leading risk factor of CAVD deaths globally, and it showed favourable trends in high SDI regions.

CONCLUSION

Although CAVD mortality reduction was observed globally, unfavourable period, and cohort effects were found in many countries. Increase of mortality rate among the population ≥85 years was the common challenge across all SDI quintiles, stressing the necessity to further improve health care for CAVD patients worldwide.

Aortic Valvular Stenosis and Heart Failure: Advances in Diagnostic, Management, and Intervention

Up to 30% of patients with aortic stenosis (AS) present with heart failure (HF) symptoms with either reduced or preserved left ventricular ejection fraction. Many of these patients present with a low-flow state, reduced aortic-valve-area (≤1.0 cm²) with low aortic-mean-gradient and aortic-peak-velocity (<40 mm Hg and <4.0 m/s). Thus, determination of true severity is essential for correct management, and multi-imaging evaluation must be performed. Medical treatment of HF is imperative and should be optimized concurrently with the determination of AS-severity. Finally, AS should be treated according to guidelines, keeping in mind that HF and low-flow increase interventions risks.

Diagnostic role of aortic valve calcium scoring in various etiologies of aortic stenosis

Most of the studies about aortic valve calcium (AVC) score in aortic stenosis (AS) were based on degenerative or bicuspid AS but not rheumatic AS. We aimed to study the diagnostic accuracy of AVC score to determine severe AS in various etiologies. Adult patients diagnosed with mild to severe AS were enrolled. AVC score were identified from multi-detector computed tomography (MDCT) scan. The AVC score was highest in bicuspid AS (3211.9 (IQR (1100.0-4562.4) AU) compared to degenerative AS (1803.7 (IQR (1073.6-2550.6) AU)), and rheumatic AS (875.6 (IQR 453.3-1594.0) AU), p < 0.001. For the ROC curve to identify severe AS, the AVC score performed well in degenerative and bicuspid AS with the area under the ROC curve (AuROC) 0.834 (95% CI, 0.730, 0.938) in degenerative group; and 0.820 (95% CI, 0.687, 0.953) in bicuspid AS. Whereas AVC score had non-significant diagnostic accuracy with AuROC 0.667 (95% CI, 0.357, 0.976) for male and 0.60(95% CI, 0.243, 0.957) for female in rheumatic AS. The cut-off AVC score values to identify severe AS were AVCS > 2028.9AU (male) and > 1082.5AU (female) for degenerative AS, and > 2431.8AU (male) and > 1293.5AU (female) for bicuspid AS. In conclusions, AVC score is the accurate test for assessing severity in patients with degenerative and bicuspid AS but performs poorly in rheumatic AS group.

Sex-Specific Differences in Aortic Valve Calcification Between Bicuspid and Tricuspid Severe Aortic Stenosis

Sex-specific thresholds of aortic valve calcification (AVC) correlate with aortic stenosis (AS) and may complement echocardiography to determine AS severity. Importantly, current guideline-recommended thresholds of AVC scores derived by multislice computed tomography do not distinguish between bicuspid and tricuspid aortic valves. The objective of this study was to evaluate the sex-specific differences in the amount of AVC in patients with severe AS and tricuspid (TAV) versus bicuspid (BAV) aortic valve morphologies, retrospectively evaluated by 2 tertiary care institutions. The inclusion criteria comprised patients with severe AS and a left ventricular ejection fraction ≥50% and suitable imaging examinations. The study included 1,450 patients (723 men; 49.9%) with severe AS, including 1,335 patients with TAV (92.1%) and 115 with BAV (17.9%). The calculated Agatston score was higher in BAV patients (men: BAV 4,358 [2,644 to 6,005] AU vs TAV 2,643 [1,727 to 3,794] AU, p <0.01; women: BAV 2,174 [1,330 to 4,378] AU vs TAV 1,703 [964 to 2,534] AU, p <0.01), also when indexed for valve dimensions and body surface area (men: BAV 2,227 [321 to 3,105] AU/m² vs TAV 1,333 [872 to 1,913] AU/m², p <0.01; women: BAV 1,326 [782 to 2,148] AU/m² vs TAV 930 [546 to 1,456] AU/m², p <0.01). Differences between the BAV- and TAV-derived Agatston score was more prominent in concordant severe AS. In conclusion, sex-specific Agatston scores in severe AS were approximately 1/3 higher in patients with BAV than in patients with TAV for both women and men. Optimal AVC thresholds should be adjusted for BAV, also respecting considerable prognostic implications.

Aortic Stenosis Progression: A Systematic Review and Meta-Analysis

BACKGROUND

Aortic valve stenosis is a progressive disorder with variable progression rates. The factors affecting aortic stenosis (AS) progression remain largely unknown.

OBJECTIVES

This systematic review and meta-analysis sought to determine AS progression rates and to assess the impact of baseline AS severity and sex on disease progression.

METHODS

The authors searched Medline, Embase, and the Cochrane Central Register of Controlled Trials from inception to July 1, 2020, for prospective studies evaluating the progression of AS with the use of echocardiography (mean gradient [MG], peak velocity [PV], peak gradient [PG], or aortic valve area [AVA]) or computed tomography (calcium score [AVC]). Random-effects meta-analysis was performed to evaluate the rate of AS progression for each parameter stratified by baseline severity, and meta-regression was performed to determine the impact of baseline severity and of sex on AS progression rate.

RESULTS

A total of 24 studies including 5,450 patients (40% female) met inclusion criteria. The pooled annualized progression of MG was +4.10 mm Hg (95% CI: 2.80-5.41 mm Hg), AVA -0.08 cm² (95% CI: 0.06-0.10 cm²), PV +0.19 m/s (95% CI: 0.13-0.24 m/s), PG +7.86 mm Hg (95% CI: 4.98-10.75 mm Hg), and AVC +158.5 AU (95% CI: 55.0-261.9 AU). Increasing baseline severity of AS was predictive of higher rates of progression for MG (P < 0.001), PV (P = 0.001), and AVC (P < 0.001), but not AVA (P = 0.34) or PG (P = 0.21). Only 4 studies reported AS progression stratified by sex, with only PV and AVC having 3 studies to perform a meta-analysis. No difference between sex was observed for PV (P = 0.397) or AVC (P = 0.572), but the level of confidence was low.

CONCLUSIONS

This study provides progression rates for both hemodynamic and anatomic parameters of AS and shows that increasing hemodynamic and anatomic baseline severity is associated with faster AS progression. More studies are needed to determine if sex differences affect AS progression. (Aortic Valve Stenosis Progression Rate: A Systematic Review and Meta-Analysis; CRD42021207726).

Heart valve disease gender difference in the era of transcatether treatment

Available data have demonstrated important sex-related differences in patients with valvular heart  disease, regarding clinical presentation, treatment, and outcomes. Although the calcific aortic  stenosis (AS) is more frequent in men compared to women, the majority of AS patients over 80  years old are women, in whom fibrotic remodeling of aortic valve is typically found. Mitral valve  disease is more common in women. However females are under-referred or delayed referrals to  treatment, probably due to the absence of sex-based LV dimension values guiding surgical timing.  The development of transcatheter devices have revolutionized the treatment of valvular heart disease and increased the interest in this topic. In this context, the consideration of gender differences in presentation, diagnosis, treatment success, and prognosis is of great importance.    

Optimal threshold score of aortic valve calcification for identification of significant aortic stenosis on non-electrocardiographic-gated computed tomography

OBJECTIVES

This study evaluated the association between aortic valve calcification (AVC) and aortic stenosis (AS) by scoring the AVC to determine the threshold scores for significant AS on non-electrocardiographic (ECG)-gated computed tomography (CT).

METHODS

We retrospectively analyzed the AVC scores of 5385 patients on non-contrast non-ECG-gated CT, who underwent transthoracic echocardiography (TTE) from March 1, 2013, to December 26, 2019, at our institution. Multivariable logistic regression models were used to identify potential risk factors for significant AS. The thresholds for significant AS were computed using receiver operator characteristic (ROC) curves, based on the AVC scores after propensity score matching.

RESULTS

A significant association was found between AS and age (p < 0.001; odds ratio [OR], 1.04; 95% confidence interval [CI], 1.02-1.06), female sex (p < 0.001; OR, 4.5; 95% CI, 2.75-7.36), bicuspid aortic valve (p < 0.001; OR, 23.2; 95% CI, 7.35-72.9), and AVC score (AVC score/100) (p < 0.001; OR, 1.82; 95% CI, 1.71-1.95). All sex-specific AVC thresholds for significant AS (moderate and over AS severity, moderate and over AS severity without discordance, discordant severe AS, and concordant severe AS) showed high sensitivity and specificity (AUC, 0.939-0.968; sensitivity, 84.6-96%; specificity, 84.2-97.1%).

CONCLUSIONS

We determined the optimal AVC threshold scores for significant AS, which may aid in diagnosing significant asymptomatic AS on incidental detection of AVC through non-ECG-gated CT for non-cardiac indications.

KEY POINTS

• Increased frequency of non-electrocardiographic (ECG)-gated computed tomography (CT) for non-cardiac indications has led to the increased incidental identification of aortic valve calcification (AVC). • It is important to identify patients with significant aortic stenosis (AS) who require additional echocardiographic assessment on incidental detection of AVC via non-ECG-gated CT. • We determined the AVC thresholds with high sensitivity and specificity to identify significant AS on non-ECG-gated CT, which could lead to early diagnosis of asymptomatic significant AS and improved prognosis.

Sex-specific aortic valve calcifications in patients undergoing transcatheter aortic valve implantation

AIMS

To study sex-specific differences in the amount and distribution of aortic valve calcification (AVC) and to correlate the AVC load with paravalvular leakage (PVL) post-transcatheter aortic valve intervention (TAVI).

METHODS AND RESULTS

This registry included 1801 patients undergoing TAVI with a Sapien3 or Evolut valve in two tertiary care institutions. Exclusion criteria encompassed prior aortic valve replacement, suboptimal multidetector computed tomography (MDCT) quality, and suboptimal transthoracic echocardiography images. Calcium content and distribution were derived from MDCT. In this study, the median age was 81.7 (25th-75th percentile 77.5-85.3) and 54% male. Men, compared to women, were significantly younger [81.2 (25th-75th percentile 76.5-84.5) vs. 82.4 (78.2-85.9), P ≤ 0.01] and had a larger annulus area [512 mm2 (25th-75th percentile 463-570) vs. 405 mm2 (365-454), P < 0.01] and higher Agatston score [2567 (25th-75th percentile 1657-3913) vs. 1615 (25th-75th percentile 905-2484), P < 0.01]. In total, 1104 patients (61%) had none-trace PVL, 648 (36%) mild PVL, and 49 (3%) moderate PVL post-TAVI. There was no difference in the occurrence of moderate PVL between men and women (3% vs. 3%, P = 0.63). Cut-off values for the Agatston score as predictor for moderate PVL based on the receiver-operating characteristic curve were 4070 (sensitivity 0.73, specificity 0.79) for men and 2341 (sensitivity 0.74, specificity 0.73) for women.

CONCLUSION

AVC is a strong predictor for moderate PVL post-TAVI. Although the AVC load in men is higher compared to women, there is no difference in the incidence of moderate PVL. Sex-specific Agatston score cut-offs to predict moderate PVL were almost double as high in men vs. women.

Osteopontin activity modulates sex-specific calcification in engineered valve tissue mimics

Patients with aortic valve stenosis (AVS) have sexually dimorphic phenotypes in their valve tissue, where male valvular tissue adopts a calcified phenotype and female tissue becomes more fibrotic. The molecular mechanisms that regulate sex-specific calcification in valvular tissue remain poorly understood. Here, we explored the role of osteopontin (OPN), a pro-fibrotic but anti-calcific bone sialoprotein, in regulating the calcification of female aortic valve tissue. Recognizing that OPN mediates calcification processes, we hypothesized that aortic valvular interstitial cells (VICs) in female tissue have reduced expression of osteogenic markers in the presence of elevated OPN relative to male VICs. Human female valve leaflets displayed reduced and smaller microcalcifications, but increased OPN expression relative to male leaflets. To understand how OPN expression contributes to observed sex dimorphisms in valve tissue, we employed enzymatically degradable hydrogels as a 3D cell culture platform to recapitulate male or female VIC interactions with the extracellular matrix. Using this system, we recapitulated sex differences observed in human tissue, specifically demonstrating that female VICs exposed to calcifying medium have smaller mineral deposits within the hydrogel relative to male VICs. We identified a change in OPN dynamics in female VICs in the presence of calcification stimuli, where OPN deposition localized from the extracellular matrix to perinuclear regions. Additionally, exogenously delivered endothelin-1 to encapsulated VICs increased OPN gene expression in male cells, which resulted in reduced calcification. Collectively, our results suggest that increased OPN in female valve tissue may play a sex-specific role in mitigating mineralization during AVS progression.

Multimodality Imaging to Explore Sex Differences in Aortic Stenosis

The aim of this article is to review sex differences in aortic stenosis (AS) assessed with multimodality imaging. Echocardiography remains the mainstay imaging technique to diagnose AS and provides important insights into the differences between men and women in relation to valve haemodynamic and left-ventricular response. However, echocardiography does not have adequate resolution to provide important insights into sex differences in the degenerative, calcific pathophysiological process of the aortic valve. CT shows that women with AS have more fibrotic changes of the aortic valve whereas men show more calcific deposits. Cardiac magnetic resonance shows that women have left ventricles that are less hypertrophic and smaller compared with those of men, while men have more replacement myocardial fibrosis. These differences may lead to different responses to aortic valve replacement because myocardial diffuse fibrosis but not replacement myocardial fibrosis may regress after the procedure. Sex differences in the pathophysiological process of AS can be assessed using multimodality imaging, assisting in decisionmaking in these patients.

Sex-specific correlates of valvular and arterial calcification burden in patients with moderate aortic stenosis

INTRODUCTION

There are significant sex differences in the prevalence and severity of cardiac calcifying processes. Women harbour more severe mitral annular calcification (MAC), while men exhibit worse aortic valve (AVC) and coronary artery (CAC) calcification. To better understand these differences, we investigated the correlates of cardiac calcification according to sex.

METHODS

We conducted a cross-sectional study of 406 patients with ≥mild aortic stenosis (AS) defined by an aortic valve area ≤1.5 cm², a peak aortic jet velocity >2.0 m/s, or a mean transvalvular gradient >15 mm Hg. Doppler-echocardiography and non-contrast multidetector CT were performed concomitantly to assess AS and cardiac calcifications.

RESULTS

Mean age was 71±11 years and 33% were women. The AS haemodynamics were not significantly different between sexes (all p>0.50), with a mean indexed aortic valve area of 0.59±0.21 cm²/m², peak aortic jet velocity of 2.78 (2.37-3.68) m/s, and mean gradient of 17.9 (12.8-31.3) mm Hg for the whole cohort. Compared with men, women harboured lower AVC (480 (222-1191) vs 1003 (484-2329) Agatston unit, AU; p<0.0001) and CAC (366 (50-914) vs 618 (167-1357) AU; p=0.007), but more severe MAC (60 (1-887) vs 48 (0-351) AU; p=0.08) and ascending aorta calcification (227 (43-863) vs 142 (7-493) AU; p=0.03). After comprehensive adjustment, sex remained an independent predictor of each cardiac calcification subtype (all p<0.02) except for the ascending aorta (p=0.32). In multivariable analysis, certain variables, like age or bicuspid aortic valve, were associated with the calcification scores in both sexes. Sex-specific predictors of calcification burden were absence of angiotensin receptor blockers (β=-0.26; p=0.007) and renal impairment (β=0.26; p=0.003) for AVC, and bisphosphonates (β=0.20; p=0.05) for CAC in women; coronary artery disease (β=0.25; p=0.001) for AVC, and angiotensin receptor blockers (β=0.19; p=0.02) and calcium/vitamin D (β=0.15; p=0.02) for MAC in men.

CONCLUSION

In AS, factors associated with cardiac valvular and arterial calcification differ between sexes, suggesting an important contributory role of sex in the pathophysiology of these calcifying processes.

Sex-Specific Considerations in Degenerative Aortic Stenosis for Female-Tailored Transfemoral Aortic Valve Implantation Management

The impact of sex on pathophysiological processes, clinical presentation, treatment options, as well as outcomes of degenerative aortic stenosis remain poorly understood. Female patients are well represented in transfemoral aortic valve implantation (TAVI) trials and appear to derive favorable outcomes with TAVI. However, higher incidences of major bleeding, vascular complications, and stroke have been reported in women following TAVI. The anatomical characteristics and pathophysiological features of aortic stenosis in women might guide a tailored planning of the percutaneous approach. We highlight whether a sex-based TAVI management strategy might impact on clinical outcomes. This review aimed to evaluate the impact of sex from diagnosis to treatment of degenerative aortic stenosis, discussing the latest evidence on epidemiology, pathophysiology, clinical presentation, therapeutic options, and outcomes. Furthermore, we focused on technical sex-oriented considerations in TAVI including the preprocedural screening, device selection, implantation strategy, and postprocedural management.

Characterization of the sex-specific pattern of angiogenesis and lymphangiogenesis in aortic stenosis

Objective

We aim to analyze sex-related differences in angiogenesis and lymphangiogenesis in aortic valves (AVs) and valve interstitial cells (VICs) from aortic stenosis (AS) patients.

Approach and Results

Totally 230 patients (59% men) with severe AS undergoing surgical valve replacement were recruited. The density of total neovessels was higher in AVs from men as compared to women. Both small and medium neovessels were more abundant in men's AVs. Accordingly, male AVs exhibited higher CD31 and VE-cadherin expressions. The levels of the pro-angiogenic markers, such as vascular endothelial growth factor (VEGF)-A, VEGF receptor (VEGFR)1, VEGFR2, insulin-like growth factor-binding protein-2 (IGFBP-2), interleukin (IL)-8, chemerin, and fibroblast growth factor (FGF)-7, were increased in AVs from men. Transforming growth factor-β expression was higher in male AVs. The expression of antiangiogenic molecules thrombospondin (Tsp)-1, endostatin, and CD36 was upregulated in male AVs, although the levels of Tsp-2, IL-4, IL-12p70, and chondromodulin-1 were similar between both sexes. The number of lymphatic vessels and the expression of the lymphangiogenic markers Lyve-1 and D2-40 was higher in men's AV as well as VEGF-C, VEGF-D, and VEGFR3. Multivariate analyses adjusted for confounders further validated the sex-dependent expression of these targets. VICs isolated from men's AVs secreted higher amounts of the pro-angiogenic factors, VEGF-A, VEGFR1, IGFBP-2, and FGF-7, as well as the pro-lymphangiogenic factors, VEGF-C, VEGF-D, and VEGFR3, than women without changes in antiangiogenic markers.

Conclusion

Our data show that aberrant angiogenic and lymphangiogenic cues are over-represented in male AVs. Importantly, the VIC is a relevant source of multiple morphogens involved in angiogenesis and lymphangiogenesis likely endowing the AV of men with the predominant calcific AS phenotypes.

Sex differences in aortic stenosis: Identification of knowledge gaps for sex-specific personalized medicine

Objectives

This review summarizes sex-based differences in aortic stenosis (AS) and identifies knowledge gaps that should be addressed by future studies.

Background

AS is the most common valvular heart disease in developed countries. Sex-specific differences have not been fully appreciated, as a result of widespread under diagnosis of AS in women.

Summary

Studies including sex-stratified analyses have shown differences in pathophysiology with less calcification and more fibrosis in women's aortic valve. Women have impaired myocardial perfusion reserve and different compensatory response of the left ventricle (LV) to pressure overload, with concentric remodeling and more diffuse fibrosis, in contrast to men with more focal fibrosis and more dilated/eccentrically remodeled LV. There is sex difference in clinical presentation and anatomical characteristics, with women having more paradoxical low-flow/low-gradient AS, under-diagnosis and severity underestimated, with less referral to aortic valve replacement (AVR) compared to men. The response to therapies is also different: women have more adverse events with surgical AVR and greater survival benefit with transcatheter AVR. After AVR, women would have more favorable LV remodeling, but sex-related differences in changes in myocardial reserve flow need future research.

Conclusions

Investigation into these described sex-related differences in AS offers potential utility for improving prevention and treatment of AS in women and men. To better understand sex-based differences in pathophysiology, clinical presentation, and response to therapies, sex-specific critical knowledge gaps should be addressed in future research for sex-specific personalized medicine.

Sex Difference in Outcomes Following Transcatheter Aortic Valve Replacement in Bicuspid Aortic Stenosis

BACKGROUND

It is unknown whether the sex difference whereby female transcatheter aortic valve replacement (TAVR) candidates had a lower risk profile, a higher incidence of in-hospital complications, but more favorable short- and long-term survival observed in tricuspid cohorts undergoing TAVR would persist in patients with bicuspid aortic valves (BAVs).

OBJECTIVES

The aim of this study was to reexamine the impact of sex on outcomes following TAVR in patients with BAVs.

METHODS

In this single-center study, patients with BAVs undergoing TAVR for severe aortic stenosis from 2012 to 2021 were retrospectively included. Baseline characteristics, aortic root anatomy, and in-hospital and 1-year valve hemodynamic status and survival were compared between sexes.

RESULTS

A total of 510 patients with BAVs were included. At baseline, women presented with fewer comorbidities. Men had a greater proportion of Sievers type 1 BAV, higher calcium volumes (549.2 ± 408.4 mm³ vs 920.8 ± 654.3 mm³; P < 0.001), and larger aortic root structures. Women experienced more vascular complications (12.9% vs 4.9%; P = 0.002) and bleeding (11.1% vs 5.3%; P = 0.019) and higher residual gradients (16.9 ± 7.7 mm Hg vs 13.2 ± 6.4 mm Hg; P < 0.001), while men were more likely to undergo second valve implantations during index TAVR (6.3% vs 15.9%; P = 0.001). Death at 1 year was not significantly different between sexes (HR: 1.15; 95% CI: 0.56-2.35; P = 0.70). Bleeding (adjusted HR: 4.62; 95% CI: 1.51-14.12; P = 0.007) was the single independent predictor of 1-year death for women.

CONCLUSIONS

In patients with BAVs undergoing TAVR, women presented with fewer comorbidities, while men had a greater proportion of type 1 BAV, more calcification, and larger aortic roots. In-hospital outcomes favored men, with fewer complications except for the need for second valve implantation, but 1-year survival was comparable between sexes.

Sex Differences in the Impact of Aortic Valve Calcium Score on Mortality After Transcatheter Aortic Valve Replacement

BACKGROUND

Transcatheter aortic valve replacement (TAVR) is now an approved alternative to surgical aortic valve replacement for the treatment of severe aortic stenosis. As the clinical adoption of TAVR expands, it remains important to identify predictors of mortality after TAVR. We aimed to evaluate the impact of sex differences in aortic valve calcium score (AVCS) on long-term mortality following TAVR in a large patient sample.

METHODS

We included consecutive patients who successfully underwent TAVR for treatment of severe native aortic valve stenosis from June 2010 to May 2021 across all US Mayo Clinic sites with follow-up through July 2021. AVCS values were obtained from preoperative computed tomography of the chest. Additional clinical data were abstracted from medical records. Kaplan-Meier curves and Cox-proportional hazard regression models were employed to evaluate the effect of AVCS on long-term mortality.

RESULTS

A total of 2543 patients were evaluated in the final analysis. Forty-one percent were women, median age was 82 years (Q1: 76, Q3: 86), 18.4% received a permanent pacemaker following TAVR, and 88.5% received a balloon expandable valve. We demonstrate an increase in mortality risk with higher AVCS after multivariable adjustment (P<0.001). When stratified by sex, every 500-unit increase in AVCS was associated with a 7% increase in mortality risk among women (adjusted hazard ratio, 1.07 [95% CI, 1.02-1.12]) but not in men.

CONCLUSIONS

We demonstrate a notable sex difference in the association between AVCS and long-term mortality in a large TAVR patient sample. This study highlights the potential value of AVCS in preprocedural risk stratification, specifically among women undergoing TAVR. Additional studies are needed to validate this finding.

Impact of sex and sex hormones on pathophysiology and progression of aortic stenosis in a murine model

The lesions observed in AS have been shown to be sex specific, with women presenting extensive fibrotic remodeling while men developing more calcification deposit. We thus aimed to evaluate the influence of sex and sex hormones on the pathophysiology of aortic valve stenosis (AS) in our mouse model of AS. LDLr^-/- ApoB^100/100 IGF-II^+/- mice (n = 210) were separated in six different groups: (1) intact male (IM), (2) intact female (IF), (3) castrated male (CM), (4) ovariectomized females (OF), (5) CM with testosterone supplementation (CMT), and (6) OF with 17β-estradiol supplementation (OFE). Mice were fed a high-fat/high-sucrose/high-cholesterol diet for 6 months. Hemodynamic progression of AS was followed by transthoracic echocardiography (at 12 and 36 weeks) and analyzed in all mice alive at 36 weeks. Aortic valves were collected for histological and digital droplet PCR* analysis. Increases in peak velocity were comparable in IF and IM (24.2 ± 5.7 vs. 25.8 ± 5.3 cm/s; p = 0.68), but IF presented with less severe AS. Between the three groups of male mice, AS progression was more important in IM (increase in peak velocity: 24.2 ± 5.7 cm/s; p < 0.001) compared to CM (6.2 ± 1.4; p = 0.42), and CMT (15.1 ± 3.5; p = 0.002). In the three groups of female mice, there were no statistical differences in AS progression. Digital PCR analysis revealed an important upregulation of the osteogenic gene RunX2 in IM (p < 0.0001) and downregulation of the pro-calcifying gene ALPL in IF (p < 0.05). Male sex and testosterone play an important role in upregulation of pro-calcifying genes and hemodynamic progression of AS. However, female mice appeared to be protected against calcification, characterized by downregulation of pro-osteogenic genes, but presented a similar AS hemodynamic progression.

Models and Techniques to Study Aortic Valve Calcification in Vitro, ex Vivo and in Vivo. An Overview

Aortic valve stenosis secondary to aortic valve calcification is the most common valve disease in the Western world. Calcification is a result of pathological proliferation and osteogenic differentiation of resident valve interstitial cells. To develop non-surgical treatments, the molecular and cellular mechanisms of pathological calcification must be revealed. In the current overview, we present methods for evaluation of calcification in different ex vivo, in vitro and in vivo situations including imaging in patients. The latter include echocardiography, scanning with computed tomography and magnetic resonance imaging. Particular emphasis is on translational studies of calcific aortic valve stenosis with a special focus on cell culture using human primary cell cultures. Such models are widely used and suitable for screening of drugs against calcification. Animal models are presented, but there is no animal model that faithfully mimics human calcific aortic valve disease. A model of experimentally induced calcification in whole porcine aortic valve leaflets ex vivo is also included. Finally, miscellaneous methods and aspects of aortic valve calcification, such as, for instance, biomarkers are presented.

Revisiting the Aortic Valve Calcium Score in Evaluating the Severity of Aortic Stenosis in Japanese Patients - A Single-Center Study

Background: In patients with aortic stenosis (AS), measurement of aortic valve calcification (AVC) using computed tomography (CT) is recommended in cases where echocardiographic measurements are inconclusive. However, sex-specific AVC thresholds proposed in the guidelines for predicting severe AS (women: 1,200 arbitrary units [AU]; men: 2,000 AU) are based on studies from Western countries. Methods and Results: We retrospectively included 512 Japanese patients with at least moderate AS who underwent transthoracic echocardiography and CT. AVC was quantified using the Agatston method. AVC was positively correlated with peak aortic jet velocity and mean transvalvular gradient (mPG), and negatively correlated with aortic valve area (AVA) and the AVA index (AVAi). In 257 patients with concordant AS grading (152 severe AS [AVAi ≤0.6 cm2/m2, mPG ≥40 mmHg], 105 moderate AS [AVAi >0.6 cm2/m2, mPG <40 mmHg]), receiver operating characteristic curve analysis of AVC predicting severe AS yielded an area under the curve of 0.91 (95% confidence interval [CI] 0.87-0.95; P<0.001) in women and 0.86 (95% CI 0.75-0.98; P<0.001) in men. The optimal thresholds (women: 1,379 AU; men: 1,802 AU) were close to those proposed in the guidelines. The diagnostic accuracy of the thresholds in the guidelines was similar to that of the optimal thresholds. Conclusions: The sex-specific AVC thresholds proposed in international guidelines can be applied to Japanese AS patients, yielding similar diagnostic accuracy as the optimal cut-off derived from the study patients.