Aortic valve sclerosis and clinical outcomes: moving toward a definition

Association between serum phosphate, magnesium, calcium and aortic valve sclerosis: a propensity score-matched case-control study

OBJECTIVES

Aortic valve sclerosis has been proposed to signify greater cardiovascular risk; the correlation between serum trace elements and aortic valve sclerosis has been reported. Therefore, an in-depth exploration of the risk factors for aortic valve sclerosis and early intervention may reduce the risk of cardiovascular disease.

METHODS

In this study, Patients with aortic valve sclerosis and non-aortic valve sclerosis who underwent echocardiographic diagnosis in the People's Hospital of Xinjiang Uygur Autonomous Region during the period from 2019 to 2021 were selected for this study. The correlation between aortic valve sclerosis and serum phosphorus, calcium, and magnesium levels was explored using the propensity score matching technique by pairing the two groups of patients 1:1.

RESULTS

A total of 1,533 non-aortic valve sclerosis and 1,533 aortic valve sclerosis patients were included. Logistic regression analysis showed that serum magnesium [OR: 0.346; 95%CI: 0.227, 0.528] and serum calcium [OR: 7.022; 95%CI: 4.755, 10.369] were influential factors. Patients with low, intermediate, and high serum magnesium levels had a significantly lower risk of aortic valve sclerosis compared to patients with very low micronutrient levels (p < 0.05). Comparatively, patients with low or high serum calcium levels had an elevated risk of aortic valve sclerosis (p < 0.05).

CONCLUSION

Serum magnesium may have a protective role against aortic valve sclerosis, while both low and high levels of serum calcium could be risk factor for the condition. These serum micronutrients may be indications of cardiovascular disease risk prediction or prevention, and more research is required.

Relationship between peak aortic jet velocity and progression of aortic stenosis in patients undergoing hemodialysis

BACKGROUND

The natural history of aortic stenosis (AS) progression, especially before severe AS development, is not well documented. We aimed to investigate the time course of peak aortic jet velocity (Vmax) and AS progression risk according to baseline Vmax, particularly whether there is a Vmax threshold.

METHODS

In a retrospective multicenter cohort study of patients on hemodialysis with aortic valve calcification, we investigated the time series of Vmax and the relationship between the baseline Vmax and progression to severe AS by analyzing longitudinal echocardiographic data.

RESULTS

Among 758 included patients (mean age, 71 years; 65% male), patients with Vmax <1.5, 1.5-1.9, 2.0-2.4, 2.5-2.9, and 3.0-3.9 m/s were 395 (52%), 216 (29%), 85 (11%), 39 (5.1%), and 23 (3.0%), respectively. The Vmax slope was gradual (mean 0.05-0.07 m/s/year) at Vmax <2 m/s, but steeper (mean 0.13-0.21 m/s/year) at Vmax ≥2 m/s. During a median 3.2-year follow-up, 52 (6.9%) patients developed severe AS. While patients with Vmax <2 m/s rarely developed severe AS, the risk of those with Vmax ≥2 m/s increased remarkably with an increasing baseline Vmax; the adjusted incidence rates in patients with Vmax <1.5, 1.5-1.9, 2.0-2.4, 2.5-2.9, and 3.0-3.9 m/s were 0.59, 0.57, 4.25, 13.8, and 56.1 per 100 person-years, respectively; the adjusted hazard ratio per 0.2 m/s increase in the baseline Vmax was 1.49 (95% confidence interval: 1.32-1.68) when Vmax ≥2 m/s.

CONCLUSIONS

The risk of progression to severe AS increased with the baseline Vmax primarily at ≥2 m/s; a Vmax threshold of 2 m/s was observed.

Non-stenotic fibro-calcific aortic valve as a predictor of myocardial infarction recurrence

BACKGROUND

Patients with acute myocardial infarction (AMI) are at increased risk of recurrent cardiovascular events. Non-stenotic aortic valve fibro-calcific remodeling (AVSc), reflecting systemic damage, may serve as a new marker of risk.

OBJECTIVES

To stratify subgroups of AMI patients with specific probabilities of recurrent AMI and to evaluate the importance of AVSc in this setting.

METHODS

Consecutive AMI patients (n = 2530) were admitted at Centro Cardiologico Monzino (2010-2019) and followed up for 5 years. Patients were divided into study (n = 1070) and test (n = 966) cohorts. Topological data analysis (TDA) was used to stratify patient subgroups, while Kaplan-Meier and Cox regressions analyses were used to evaluate the significance of baseline characteristics.

RESULTS

TDA identified 11 subgroups of AMI patients with specific baseline characteristics. Two subgroups showed the highest rate of reinfarction after 5 years from the indexed AMI with a combined hazard ratio (HR) of 3.8 (95%CI: 2.7-5.4) compared to the other subgroups. This was confirmed in the test cohort (HR = 3.1; 95%CI: 2.2-4.3). These two subgroups were mostly men, with hypertension and dyslipidemia, who exhibit higher prevalence of AVSc, higher levels of high-sensitive c-reactive protein and creatinine. In the year-by-year analysis, AVSc, adjusted for all confounders, showed an independent association with the increased risk of reinfarction (odds ratio of ∼2 at all time-points), in both the study and the test cohorts (all p < 0.01).

CONCLUSIONS

AVSc is a crucial variable for identifying AMI patients at high risk of recurrent AMI and its presence should be considered when assessing the management of AMI patients. The inclusion of AVSc in risk stratification models may improve the accuracy of predicting the likelihood of recurrent AMI, leading to more personalized treatment decisions.

Whole-Blood Transcriptome Unveils Altered Immune Response in Acute Myocardial Infarction Patients With Aortic Valve Sclerosis

BACKGROUND

Aortic valve sclerosis (AVSc) presents similar pathogenetic mechanisms to coronary artery disease and is associated with short- and long-term mortality in patients with coronary artery disease. Evidence of AVSc-specific pathophysiological traits in acute myocardial infarction (AMI) is currently lacking. Thus, we aimed to identify a blood-based transcriptional signature that could differentiate AVSc from no-AVSc patients during AMI.

METHODS

Whole-blood transcriptome of AVSc (n=44) and no-AVSc (n=66) patients with AMI was assessed by RNA sequencing on hospital admission. Feature selection, differential expression, and enrichment analyses were performed to identify gene expression patterns discriminating AVSc from no-AVSc and infer functional associations. Multivariable Cox regression analysis was used to estimate the hazard ratios of cardiovascular events in AVSc versus no-AVSc patients.

RESULTS

This cross-sectional study identified a panel of 100 informative genes capable of distinguishing AVSc from no-AVSc patients with 94% accuracy. Further analysis revealed significant mean differences in 143 genes, of which 30 genes withstood correction for age and previous AMI or coronary interventions. Functional inference unveiled a significant association between AVSc and key biological processes, including acute inflammatory responses, type I IFN (interferon) response, platelet activation, and hemostasis. Notably, patients with AMI with AVSc exhibited a significantly higher incidence of adverse cardiovascular events during a 10-year follow-up period, with a full adjusted hazard ratio of 2.4 (95% CI, 1.3-4.5).

CONCLUSIONS

Our findings shed light on the molecular mechanisms underlying AVSc and provide potential prognostic insights for patients with AMI with AVSc. During AMI, patients with AVSc showed increased type I IFN (interferon) response and earlier adverse cardiovascular outcomes. Novel pharmacological therapies aiming at limiting type I IFN response during or immediately after AMI might improve poor cardiovascular outcomes of patients with AMI with AVSc.

FIB-4 liver fibrosis index correlates with aortic valve sclerosis in non-alcoholic population

AIM

Hepatic fibrosis, a progressive scarring of liver tissue, is commonly caused by non-alcoholic fatty liver disease (NAFLD), which increases the risk of cardiovascular disease. The Fibrosis-4 (FIB-4) index is a non-invasive tool used to assess liver fibrosis in patients with NAFLD. Aortic valve sclerosis (AVS), a degenerative disorder characterized by thickening and calcification of valve leaflets, is prevalent in the elderly and associated with increased cardiovascular morbidity and mortality. Recent studies have suggested that AVS may also be linked to other systemic diseases such as liver fibrosis. This study aimed to investigate the relationship between the FIB-4 index and AVS in a non-alcoholic population, with the hypothesis that the FIB-4 index could serve as a potential marker for AVS.

METHOD

A total of 92 patients were included in this study. AVS was detected using transthoracic echocardiography, and patients were divided into groups according to the presence of AVS. The FIB-4 index was calculated for all patients and compared between the groups.

RESULTS

A total of 17 (18.4%) patients were diagnosed AVS. Patients with AVS had higher rates of diabetes mellitus, older age, hypertension, angiotensin-converting enzyme inhibitor use, higher systolic blood pressure (BP) and diastolic BP in the office, coronary artery disease prevalence, left atrial volume index (LAVI), left ventricular mass index (LVMI), and late diastolic peak flow velocity (A) compared to those without AVS. Moreover, AVS patients had significantly higher creatinine levels and lower estimated glomerular filtration rate. Remarkably, the FIB-4 index was significantly higher in patients with AVS. In univariate and multivariate analyses, higher systolic BP in the office (OR, 1.044; 95% CI 1.002-1.080, p = .024) and higher FIB-4 index (1.46 ± .6 vs. .91 ± .46, p < .001) were independently associated with AVS.

CONCLUSION

Our findings suggest that the FIB-4 index is associated with AVS in non-alcoholic individuals. Our results highlight the potential utility of the FIB-4 index as a non-invasive tool for identifying individuals at an increased risk of developing AVS.

Open-Heart Cardio-Thoracic Biological Valve Replacement Following Complicated Transcatheter Aortic Valve Implantation

Transcatheter aortic valve implantation (TAVI) is currently becoming the method of choice in high-risk patients with severe aortic valve stenosis. Post-TAVI complications are more common owing to the increasing use of the method. The majority of TAVI complications derive from concomitant aortic stenosis with moderate/severe aortic insufficiency, paravalvular leak, and atrioventricular block. The contemporary TAVI qualification process includes a thorough echocardiography and angio-CT of the aorta, which is crucial in assessing valve measurements, determining the position of the coronary arteries branching from the aorta, and choosing the optimal valve size. We present the case report of an 81-year-old patient admitted to our hospital because of exacerbation of the clinical condition and development of pulmonary edema a few days after TAVI. Despite the reduction of the initial leak, an echocardiographic examination revealed the remaining severe paravalvular aortic leakage. We performed open-heart cardio-thoracic surgery, explanted the TAVI valve, and implanted the biological prosthesis (Edwards Perimount Magna size 25). Introduction of new interventional treatment approaches and the availability of imaging tools have substantially reduced the incidence of significant paravalvular leak and offered a better prognosis for patients undergoing TAVI.

Risk score for coronary heart disease (CHD-RISK) and hemodynamically significant aortic valve stenosis

BACKGROUND AND AIM

Multiple studies have investigated the association between coronary heart disease (CHD) risk factors and aortic valve stenosis (AS). However, limited studies have explored the relationship between CHD risk scores and AS. Whether incident risk scores for coronary heart disease (CHD-RISK) may be applied to predict AS remains unclear. We aim to investigate the association between AS and CHD-RISK.

METHODS AND RESULTS

We included 4791 participants (age 54.6 ± 5.0 yrs, 58.7% women, 81% were of European origin), and CHD-RISK was estimated in 1990-1992. The participants were then followed-up until December 31, 2013. The primary outcome was hemodynamic significant AS identified by Doppler echocardiography in 2011-2013. We used multivariate-logistic regression models to assess the associations between CHD-RISK and AS. During follow-up, 963 (20.1%) cases of AS were identified. Per-standard deviation (6%) increase in CHD-RISK was associated with OR 95% Cl [1.194, 95% CI 1.068 to 1.335, p = 0.002] risk of AS in the fully adjusted models. Results were similar when stratified by quintiles of CHD-RISK, using the lowest quintiles <0.94% of CHD-RISK as the reference, 0.94%-2.26%, 2.26%-4.83%, 4.83%-9.21%, and >9.21% were; 1.33 (95% CI, 0.99-1.78, p = 0.055), 1.64 (95% CI, 1.17-2.29, p = 0.004), 2.23 (95% CI, 1.49-3.32, p = <0.001), 2.66 (95% CI, 1.65-4.31, p = <0.001) respectively.

CONCLUSIONS

CHD-RISK was associated with AS. CHD-RISK and AS were high in females, age ≥55 yrs, current smokers, and BMI ≥ 30 kg/m². This investigation suggests CHD-RISK may be applied to forecast AS risk similar to CHD. Future studies are required to detect, manage, and establish better treatment strategies in these high-risk subgroups.

Role of follistatin-like 1 levels and functions in calcific aortic stenosis

Background

Calcific aortic valve disease (CAVD) is a progressive disease resulting in severe calcific aortic stenosis (AS), and there is increasing interest in the discovery of novel biomarkers to identify patients with potential future calcific AS at an early stage. This study aimed to determine whether follistatin-like 1 (FSTL1) is associated with calcific AS events and its exact role in aortic valve calcification.

Methods

A prospective observational cohort study involving 656 patients was performed to investigate the relationship between serum FSTL1 and calcific AS incidence during a follow-up of 5 years. Furthermore, we detected FSTL1 levels in valvular interstitial cells (VICs) from calcified valves and explored the effects of FSTL1 on VIC osteogenic differentiation in vitro as well as the signaling pathways involved.

Results

During a median follow-up of 5 years, lower FSTL1 levels were associated with a significantly higher risk of calcific AS events (log rank test, P = 0.007). In addition, Cox multivariable regression analyses verified the predictive value of FSTL1 after adjusting for both demographic features and laboratory confounders. Consistent with our results for serum, a lower concentration of FSTL1 was observed in calcified human valves (n = 11) and mainly colocalized with VICs. Recombinant human FSTL1 (rhFSTL1) stimulation inhibited calcium deposition, alkaline phosphatase (ALP) activity, and osteogenic gene expression partly through the downregulation of the ERK1/2 pathway.

Conclusion

Taken together, this study provides a strong rationale to consider FSTL1 as a potential therapeutic target for calcific AS.

Application of a Novel Two-Dimensional Echocardiographic Calcium Quantification Method to Assess All Severities of Aortic Stenosis

BACKGROUND

Aortic valve (AV) calcification (AVC) is a strong predictor of aortic stenosis (AS) severity. The two-dimensional AVC (2D-AVC) ratio, a gain-independent ratio composed of the average pixel density of the AV and the aortic annulus, has previously shown strong correlations with two-dimensional (2D) echocardiographic hemodynamic parameters for severe AS and AVC by cardiac computed tomography. We hypothesize that the 2D-AVC ratio correlates with hemodynamic parameters in all severities of AS.

METHODS

A total of 285 patients with a normal AV (n = 49), aortic sclerosis (n = 75), or mild (n = 38), moderate (n = 72), or severe (n = 51) AS undergoing 2D echocardiography were retrospectively evaluated, and the 2D-AVC ratios were correlated to mean AV gradient, peak AV velocity, AV area, and dimensionless index. The 2D-AVC ratios of various AS severities were compared against each other via area under the curve (AUC) analysis.

RESULTS

The 2D-AVC ratio is strongly correlated with mean AV gradient (r = 0.79, P < .0001) and peak AV velocity (r = 0.78, P < .0001). There was moderate correlation with the AV area (r = -0.58, P < .0001) and dimensionless index (r = -0.67, P < .0001) across all AS severities. The 2D-AVC ratio also distinguished nonmoderate AS (mild AS + normal AV) from moderate or greater (moderate + severe) AS (AUC = 0.93) and moderate versus severe AS (AUC = 0.88).

CONCLUSION

The 2D-AVC ratio exhibits moderate to strong correlation with 2D echocardiographic hemodynamic parameters across all severities of AS.

Enduring Reactive Oxygen Species Emission Causes Aberrant Protein S-Glutathionylation Transitioning Human Aortic Valve Cells from a Sclerotic to a Stenotic Phenotype

Aims: During calcific aortic valve stenosis (CAVS) progression, oxidative stress and endothelial dysfunction mark the initial pathogenic steps with a parallel dysregulation of the antioxidant systems. Here, we tested whether oxidation-induced protein S-glutathionylation (P-SSG) accounts for a phenotypic switch in human aortic valvular tissue, eventually leading to calcium deposition. Next, we tested whether countering this reactive oxygen species (ROS) surge would prevent these perturbations. Results: We employed state-of-the-art technologies, such as electron paramagnetic resonance (EPR), liquid chromatography-tandem mass spectrometry, imaging flow-cytometry, and live-cell imaging on human excised aortic valves and primary valve endothelial cells (VECs). We observed that a net rise in EPR-detected ROS emission marked the transition from fibrotic to calcific in human CAVS specimens, coupled to a progressive increment in P-SSG deposition. In human VECs (hVECs), treatment with 2-acetylamino-3-[4-(2-acetylamino-2-carboxyethylsulfanylthiocarbonylamino)phenylthiocarbamoylsulfanyl]propionic acid triggered highly oxidizing conditions prompting P-SSG accumulation, damaging mitochondria, and inducing endothelial nitric oxide synthase uncoupling. All the events conjured up in morphing these cells from their native endothelial phenotype into a damaged calcification-inducing one. As proof of principle, the use of the antioxidant N-acetyl-L-cysteine prevented these alterations. Innovation: Borne as a compensatory system to face excessive oxidative burden, with time, P-SSG contributes to the morphing of hVECs from their innate phenotype into a damaged one, paving the way to calcium deposition. Conclusion: Our data suggest that, in the human aortic valve, unremitted ROS emission along with a P-SSG build-up occurs and accounts, at least in part, for the morphological/functional changes leading to CAVS. Antioxid. Redox Signal. 37, 1051-1071.

NAFLD in Cardiovascular Diseases: A Contributor or Comorbidity?

Nonalcoholic fatty liver disease (NAFLD) and cardiovascular diseases are both highly prevalent conditions around the world, and emerging data have shown an association between them. This review found several longitudinal and cross-sectional studies showing that NAFLD was associated with coronary artery disease, cardiac remodeling, aortic valve remodeling, mitral annulus valve calcifications, diabetic cardiomyopathy, diastolic cardiac dysfunction, arrhythmias, and stroke. Although the specific underlying mechanisms are not clear, many hypotheses have been suggested, including that metabolic syndrome might act as an upstream metabolic defect, leading to end-organ manifestations in both the heart and liver. Management of NAFLD includes weight loss through lifestyle interventions or bariatric surgery, and pharmacological interventions, often targeting comorbidities. Although there are no Food and Drug Administration-approved nonalcoholic steatohepatitis-specific therapies, several drug candidates have demonstrated effect in the improvement in fibrosis or nonalcoholic steatohepatitis resolution. Further studies are needed to assess the effect of those interventions on cardiovascular outcomes, the major cause of mortality in patients with NAFLD. In conclusion, a more comprehensive, multidisciplinary approach to diagnosis and management of patients with NAFLD and cardiovascular diseases is needed to optimize clinical outcomes.

Association of the Heart Rate Variability Response to Active Standing with the Severity of Calcific Aortic Valve Disease: Novel Insights of a Neurocardiovascular Pathology

The aim of this work was to obtain insights of the participation of the autonomic nervous system in different stages of calcific aortic valve disease (CAVD) by heart rate variability (HRV) analysis. Studying subjects with no valve impairments and CAVD patients, we also sought to quantify the independent contribution or explanatory capacity of the aortic valve echocardiographic parameters involved in the HRV changes caused by active standing using hierarchical partitioning models to consider other variables or potential confounders. We detected smaller adjustments of the cardiac autonomic response at active standing caused specifically by the aortic valve deterioration. The highest association (i.e., the highest percentage of independent exploratory capacity) was found between the aortic valve area and the active standing changes in the short-term HRV scaling exponent α₁ (4.591%). The valve’s maximum pressure gradient echocardiographic parameter was present in most models assessed (in six out of eight models of HRV indices that included a valve parameter as an independent variable). Overall, our study provides insights with a wider perspective to explore and consider CAVD as a neurocardiovascular pathology. This pathology involves autonomic-driven compensatory mechanisms that seem generated by the aortic valve deterioration.

Aort Kapak Sklerozunun Öngörülmesinde Yeni Hematolojik İnflamatuar Parametrelerin Önemi

Aim: Inflammatory process plays a critical role in the progression of aortic valve sclerosis (AVS). This study aims to evaluate the haematological and biochemical inflammatory markers in AVS patients.Methods: A retrospective observational study was included consecutive 557 patients who underwent an echocardiogram between June 2021 and September 2021. The study population was divided into two groups according to the presence of AVS. The groups were compared in terms of C-reactive protein (CRP), Neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR), and monocyte-HDL cholesterol ratio (MHR).Results: The mean age was 63 ± 10 years. C-reactive protein (CRP), NLR, PLR and MHR were significantly higher in patients with AVS. The best cut-off values of the NLR were 1.4 (a sensitivity of 84%, a specificity of 74%), PLR was 116 (a sensitivity of 75%, a specificity of 54%), and MHR was 9.5 (a sensitivity of 78%, a specificity of 75%). CRP (OR: 1.246, 95% CI: 1.117 – 1.389; p &lt; 0.001), NLR (OR: 2.10, 95% CI: 1.456 – 3.032; p &lt; 0.001), and MHR (OR: 1.227, 95% CI: 1.125 – 1.339; p &lt; 0.001) were independent predictors of the AVS when NLR and MHR analysed as a continuous variable. Using a cut off level of NLR &gt; 1.4 (OR: 4.825, 95% CI: 2.430 – 9.583; p &lt; 0.001) and MHR &gt; 9.5 (OR: 13.937, 95% CI: 7.464 – 26.023; p &lt; 0.001) were independent predictors of the AVS.Conclusion: Increased CRP levels, NLR and MHR were found to be independent predictors for AVS. Hematological inflammatory biomarkers are cost effective and helpful approach for prediction of AVS presence.

Purinergic Receptor P2Y2 Stimulation Averts Aortic Valve Interstitial Cell Calcification and Myofibroblastic Activation

Rationale—Calcific aortic valve stenosis (CAVS) is a pathological condition of the aortic valve with a prevalence of 3% in the general population. It is characterized by massive rearrangement of the extracellular matrix, mostly due to the accumulation of fibro-calcific deposits driven by valve interstitial cells (VIC), and no pharmacological treatment is currently available. The aim of this study was to evaluate the effects of P2Y2 receptor (P2RY2) activation on fibro-calcific remodeling of CAVS. Methods—We employed human primary VICs isolated from CAVS leaflets treated with 2-thiouridine-5′-triphosphate (2ThioUTP, 10 µM), an agonist of P2RY2. The calcification was induced by inorganic phosphate (2 mM) and ascorbic acid (50 µg/mL) for 7 or 14 days, while the 2ThioUTP was administered starting from the seventh day. 2ThioUTP was chronically administered for 5 days to evaluate myofibroblastic activation. Results—P2RY2 activation, under continuous or interrupted pro-calcific stimuli, led to a significant inhibition of VIC calcification potential (p < 0.01). Moreover, 2ThioUTP treatment was able to significantly reduce pro-fibrotic gene expression (p < 0.05), as well as that of protein α-smooth muscle actin (p = 0.004). Conclusions—Our data suggest that P2RY2 activation should be further investigated as a pharmacological target for the prevention of CAVS progression, acting on both calcification and myofibroblastic activation.

Aortic Valve Sclerosis in High-Risk Coronary Artery Disease Patients

Background: Current knowledge regarding the relationship between aortic valve sclerosis (AVSc), cardiovascular risk factors, and mortality in patients with known coronary artery disease (CAD) is still unclear. The present study aimed at investigating the prevalence of AVSc as well as its association with long-term all-cause mortality in high-risk CAD patients that has never been explored in large cohorts thus far.

Methods and Results: In this retrospective and observational cohort study we enrolled high-risk CAD patients, hospitalized at Centro Cardiologico Monzino (CCM), Milan, Italy, between January 2006 and December 2016. The morphology and function of the aortic valve were assessed from the recorded echocardiographic images to evaluate the presence of AVSc, defined as a non-uniform thickening of the aortic leaflets with no consequences on hemodynamics. Data on 5-year all-cause mortality was retrieved from a Regional database. Of the 5,489 patients initially screened, 4,938 (mean age 67 ± 11 years, 3,954 [80%] men) were enrolled in the study. In the overall population, AVSc was detected in 2,138 (43%) patients. Multivariable LASSO regression revealed that age, female gender, diabetes mellitus, previous MI, and left ventricular ejection fraction were independently associated with AVSc. All-cause mortality (adjusted hazard ratio: 1.29, 95%CI: 1.05–1.58) was significantly higher in AVSc than in non-AVSc patients.

Conclusions: AVSc is frequently detected in high-risk CAD patients and is associated with long-term mortality. Our findings corroborate the hypothesis that AVSc is an underestimated marker of systemic cardiovascular risk. Thus, AVSc detection may be used to improve long-term risk stratification of high-risk CAD patients.

All-cause and cardiovascular mortality in patients undergoing hemodialysis with aortic sclerosis and mild-to-moderate aortic stenosis: A cohort study

BACKGROUND AND AIMS

Mild-to-moderate aortic stenosis (AS) and aortic sclerosis, a precursor of AS, are associated with mortality in the general population; however, their association in patients undergoing hemodialysis with higher morbidity of AS is unknown. Thus, we investigated the mortality of aortic sclerosis and mild-to-moderate AS in patients undergoing hemodialysis.

METHODS

This was a retrospective multicenter cohort study of consecutive patients undergoing hemodialysis at nine dialysis facilities who underwent screening echocardiography between January 2008 and December 2019. We investigated the mortality of patients with aortic sclerosis or mild-to-moderate AS using multivariable Cox proportional hazards regression.

RESULTS

Among 1,878 patients undergoing hemodialysis, those with normal aortic valves, aortic sclerosis, mild AS, moderate AS, severe AS, and prosthetic aortic valves were 844 (45%), 793 (42%), 161 (8.6%), 38 (2.0%), 11 (0.6%), and 31 (1.7%), respectively. After excluding patients with severe AS and prosthetic aortic valves, we performed comparative analysis on 1,836 patients (mean age, 67 years; 66% male). In a median follow-up of 3.6 years, crude death rates (per 100 person-years) were 5.2, 10.6, and 13.0 in patients with normal aortic valves, aortic sclerosis, and mild-to-moderate AS, respectively. Compared with normal aortic valves, both aortic sclerosis and mild-to-moderate AS were associated with all-cause and cardiovascular death: adjusted hazard ratios (95% confidence intervals) were 1.36 (1.13-1.65) and 1.36 (1.02-1.80) for all-cause death; and 1.52 (1.06-2.17) and 1.74 (1.04-2.92) for cardiovascular death, respectively.

CONCLUSIONS

Aortic sclerosis and mild-to-moderate AS were independent risk factors for all-cause and cardiovascular death in patients undergoing hemodialysis.

Discordant severity criteria in patients with moderate aortic stenosis: prognostic implications

Background

The criteria to define the grade of aortic stenosis (AS)—aortic valve area (AVA) and mean gradient (MG) or peak jet velocity—do not always coincide into one grade. Although in severe AS, this discrepancy is well characterised, in moderate AS, the phenomenon of discordant grading has not been investigated and its prognostic implications are unknown.

Objectives

To investigate the occurrence of discordant grading in patients with moderate AS (defined by an AVA between 1.0 cm² and 1.5 cm² but with an MG <20 mm Hg) and how these patients compare with those with concordant grading moderate AS (AVA between 1.0 cm² and 1.5 cm² and MG ≥20 mm Hg) in terms of clinical outcomes.

Methods

From an ongoing registry of patients with AS, patients with moderate AS based on AVA were selected and classified into discordant or concordant grading (MG <20 mm Hg or ≥20 mm Hg, respectively). The clinical endpoint was all-cause mortality.

Results

Of 790 patients with moderate AS, 150 (19.0%) had discordant grading, moderate AS. Patients with discordant grading were older, had higher prevalence of previous myocardial infarction and left ventricular (LV) hypertrophy, larger LV end-diastolic and end-systolic volume index, higher LV filling pressure and lower LV ejection fraction and stroke volume index as compared with their counterparts. After a median follow-up of 4.9 years (IQR 3.0–8.2), patients with discordant grading had lower aortic valve replacement rates (26.7% vs 44.1%, p<0.001) and higher mortality rates (60.0% vs 43.1%, p<0.001) as compared with patients with concordant grading. Discordant grading moderate AS, combined with low LV ejection fraction, presented the higher risk of mortality (HR 2.78 (2.00–3.87), p<0.001).

Conclusion

Discordant-grading moderate AS is not uncommon and, when combined with low LV ejection fraction, is associated with high risk of mortality.

Aortic Valve Sclerosis as an Important Predictor of Long-Term Mortality in Patients With Carotid Atheromatous Plaque Requiring Carotid Endarterectomy

Background: A strong association between aortic valve sclerosis (AVSc), the earliest manifestation of calcific aortic valve disease, and atherosclerosis exists. The aim of the study was to evaluate the predictive capabilities of AVSc on long-term all-cause mortality, in patients requiring carotid endarterectomy (CEA).

Methods and Results: 806 consecutive CEA patients were enrolled. Preoperative echocardiography was used to assess AVSc. Computed tomography angiography was applied for plaque characterization. Kaplan-Meier curves, Cox linear regression, and area under the receiving operator characteristic (AUC) curve analyses were used to evaluate the predictive capability of AVSc. Overall, 348 of 541 patients had AVSc (64%). Age, diabetes, and estimated glomerular filtration rate (eGFR) were associated with AVSc. In the 5-year follow-up, AVSc group had a mortality rate of 16.7% while in no-AVSc group was 7.8%. Independent predictors of all-cause mortality were age, sex, eGFR, left ventricular ejection fraction, and AVSc. After adjustments, AVSc was associated with a significant increase in all-cause mortality risk (hazard ratio, HR = 1.9; 95%CI: 1.04–3.54; p = 0.038). We stratify our cohort based on carotid atheromatous plaque-type: soft, calcified, and mixed-fibrotic. In patients with mixed-fibrotic plaques, the mortality rate of AVSc patients was 15.5% compared to 2.4% in no-AVSc patients. In this group, AVSc was associated with an increased long-term all-cause mortality risk with an adjusted HR of 12.8 (95%CI: 1.71–96.35; p = 0.013), and the AUC, combing eGFR and AVSc was 0.77 (p < 0.001).

Conclusions: Our findings indicate that AVSc together with eGFR may be used to improve long-term risk stratification of patients undergoing CEA surgery.

Dissecting Calcific Aortic Valve Disease-The Role, Etiology, and Drivers of Valvular Fibrosis

Calcific aortic valve disease (CAVD) is a highly prevalent and progressive disorder that ultimately causes gradual narrowing of the left ventricular outflow orifice with ensuing devastating hemodynamic effects on the heart. Calcific mineral accumulation is the hallmark pathology defining this process; however, fibrotic extracellular matrix (ECM) remodeling that leads to extensive deposition of fibrous connective tissue and distortion of the valvular microarchitecture similarly has major biomechanical and functional consequences for heart valve function. Significant advances have been made to unravel the complex mechanisms that govern these active, cell-mediated processes, yet the interplay between fibrosis and calcification and the individual contribution to progressive extracellular matrix stiffening require further clarification. Specifically, we discuss (1) the valvular biomechanics and layered ECM composition, (2) patterns in the cellular contribution, temporal onset, and risk factors for valvular fibrosis, (3) imaging valvular fibrosis, (4) biomechanical implications of valvular fibrosis, and (5) molecular mechanisms promoting fibrotic tissue remodeling and the possibility of reverse remodeling. This review explores our current understanding of the cellular and molecular drivers of fibrogenesis and the pathophysiological role of fibrosis in CAVD.

Optical coherence tomography and multiphoton microscopy offer new options for the quantification of fibrotic aortic valve disease in ApoE-/- mice

Aortic valve sclerosis is characterized as the thickening of the aortic valve without obstruction of the left ventricular outflow. It has a prevalence of 30% in people over 65 years old. Aortic valve sclerosis represents a cardiovascular risk marker because it may progress to moderate or severe aortic valve stenosis. Thus, the early recognition and management of aortic valve sclerosis are of cardinal importance. We examined the aortic valve geometry and structure from healthy C57Bl6 wild type and age-matched hyperlipidemic ApoE-/- mice with aortic valve sclerosis using optical coherence tomography (OCT) and multiphoton microscopy (MPM) and compared results with histological analyses. Early fibrotic thickening, especially in the tip region of the native aortic valve leaflets from the ApoE-/- mice, was detectable in a precise spatial resolution using OCT. Evaluation of the second harmonic generation signal using MPM demonstrated that collagen content decreased in all aortic valve leaflet regions in the ApoE-/- mice. Lipid droplets and cholesterol crystals were detected using coherent anti-Stokes Raman scattering in the tissue from the ApoE-/- mice. Here, we demonstrated that OCT and MPM, which are fast and precise contactless imaging approaches, are suitable for defining early morphological and structural alterations of sclerotic murine aortic valves.

Heart valve calcification and cardiac hemodynamics

PURPOSE

Heart valve calcification (VC) is associated with increased cardiovascular risk, but the hemodynamic and functional profile of patients affected by VC has not been fully explored.

METHODS

The study population was formed by consecutive unselected patients included in seven echocardiographic laboratories in a 2-week period. A comprehensive echocardiographic examination was performed. VC was defined by the presence of calcification on at least one valve.

RESULTS

Population was formed of 1098 patients (mean age 65 ± 15 years; 47% female). VC was present in 31% of the overall population. Compared with subjects without VC, VC patients were older (60 ± 14 vs 75 ± 9; P < .0001), had more hypertension (40% vs 57%; P = .0005), diabetes (11% vs 18%; P = .002), coronary artery disease (22% vs 38%; P = .04), and chronic kidney disease (4% vs 8%; P = .007). Furthermore, VC patients had lower ejection fraction (55 ± 14 vs 53 ± 25; P < .0001), worse diastolic function (E/e' 8.5 ± 4.6 vs 13.0 ± 7.1; P < .0001) and higher pulmonary artery pressure (29 ± 9 vs 37 ± 12; P < .0001). The association between VC and EF was not independent of etiology (p for VC 0.13), whereas the association with E/e' and PASP was independent in a full multivariate model (P < .0001 and P = .0002, respectively).

CONCLUSION

Heart valve calcification patients were characterized by a worse functional and hemodynamic profile compared to patients with normal valve. The association between VC and diastolic function and PASP were independent in comprehensive multivariate models.

Relation of p - wave dispersion with presystolic a - wave and aortic valve sclerosis in asymptomatic subjects

BACKGROUND

P-wave duration and P-wave dispersion (PWD) are thought to be the surrogate marker of devoloping atrial fibrillation (AF). The main purpose of present study was to investigate the association between presystolic wave (PSW), aortic valve sclerosis, and PWD.

PATIENTS AND METHODS

Patients with sinus rhythm admitted to the cardiology outpatient clinic were consecutively enrolled. Maximum (Pmax) and minimum (Pmin) P-wave duration and PWD were measured. Echocardiography was used to assess the aortic valve morphology and presence of PSW. The patients were divided into two groups according to presence or absence of AVSc and PSW.

RESULTS

A total of 100 patients were enrolled consecutively. Patients with both PSW and AVSc had higher PWD values compared with those without PSW (42 ± 15 vs 65 ± 20) and AVSc (52 ± 21 vs 69 ± 19). The patients were categorized on the basis of median PWD values. According to univariate analysis, there was significant association between PWD and presence of PSW (P: .004), presence of AVS (P: .011), hypertension (P: .01) interventricular septal thickness (IVST) (P: .026), and posterior wall thickness (PWT) (P: .022). Multivariate logistic regression analyses demonstrated presence of PSW (95% confidence interval (1.058-6.505, P: .037) as an independent determinant of PWD.

CONCLUSION

Assessment of presystolic A-wave on echocardiography examination may provide important information regarding the atrial conduction velocities that is a electrophysiological cause of AF. While there was a significant association between AVSc and PWD in univariate analysis, this significance disappeared in multivariate analysis.

Clinical Relevance of Plasma Endogenous Tissue-Plasminogen Activator and Aortic Valve Sclerosis: Performance as a Diagnostic Biomarker

Background: Aortic valve sclerosis (AVSc), a common precursor to calcific aortic valve disease, may progress into advanced aortic stenosis with hemodynamic instability. However, plasma biomarkers of such a subclinical condition remain lacking. Since impaired fibrinolysis featuring dysregulated tissue plasminogen activator (t-PA) is involved in several cardiovascular diseases, we investigated whether endogenous t-PA was also associated with AVSc.

Methods: Plasma t-PA levels were measured in 295 consecutive patients undergoing standard echocardiography and Doppler flow imaging. Multiple logistic regression analyses were used to assess the association between t-PA and AVSc. Receiver operating characteristic curve analysis was performed for determining the diagnostic value of t-PA for AVSc. The performance of adding t-PA to clinical signatures of AVSc was evaluated. Concentration of t-PA was assessed in human sclerotic and non-sclerotic aortic valves by histology and immunohistochemistry analysis.

Results: Plasma t-PA was higher in patients with AVSc than in non-AVSc counterparts (median, 2063.10 vs. 1403.17 pg/mL, p < 0.01). C-statistics of plasma t-PA for discriminating AVSc was 0.698 (95%CI: 0.639–0.758). The performance of t-PA for identifying AVSc was better among male and non-hypertensive patients [C-statistics (95%CI): 0.712 (0.634–0.790) and 0.805 (0.693–0.916), respectively]. Combination of t-PA and clinical factors improved classification of the patients (category-free NRI: 0.452, p < 0.001; IDI: 0.020, p = 0.012). The concentration of t-PA was three times higher in sclerotic compared to non-sclerotic aortic valves.

Conclusion: Elevated circulating t-PA level confers an increased risk for AVSc. Further prospective studies with larger sample size are needed to examine if t-PA could serve as a diagnostic clinical marker for AVSc.

Are there any subclinical myocardial dysfunctions in subjects with aortic valve sclerosis? A 3D-speckle tracking echocardiography study

Aortic valve sclerosis (AVS) is defined as calcified and thickened aortic leaflets without restriction of leaflet motion. We have not found any studies that previously assessed the effect of AVS on myocardial functions with three dimensional-speckle tracking echocardiography (3D-STE). Therefore, we aimed to identify any early changes in left atrial (LA) myocardial dynamics and/or left ventricular (LV) systolic functions in patients with AVS using 3D-STE. Seventy-five patients with AVS and 80 age- and gender-matched controls were enrolled into the study. The baseline clinical characteristics of the study patients were recorded. Conventional 2D echocardiographic and 3D-STE analyses were performed. The LV-global longitudinal strain (LV-GLS) and LV-global circumferential strain (LV-GCS) were significantly decreased in the AVS (+) group than in the control group (p < 0.001 and p = 0.013, respectively). In multivariate logistic regression analysis; LV-GLS (p < 0.001, odds ratio (OR) = 3.16, 95% confidence interval (CI) 1.42-5.63) and Triglyceride (TG) (p = 0.033, OR = 1.29, 95% CI 1.11-1.72) were found to be independent predictors of AVS. ROC analysis was performed to find out the ideal LV-GLS cut-off value for predicting the AVS. A LV-GLS value of > - 18 has 85.8% sensitivity, 67.5% specificity for the prediction of the AVS. Our results support that subjects with AVS may have subclinical LV deformation abnormalities even though they have not LV pressure overload. According to our findings, patients with AVS should be investigated in terms of atherosclerotic risk factors, their dysmetabolic status should be evaluated and closely followed up for their progression to calcific aortic stenosis.

Characteristics and Prognosis of Patients With Moderate Aortic Stenosis and Preserved Left Ventricular Ejection Fraction

Background

Moderate aortic stenosis (MAS) has not been extensively studied and characterized, as no published study has been specifically devoted to this condition.

Methods and Results

We aimed to describe the characteristics of patients with MAS and to evaluate their long‐term survival compared with that of the general population. This study included 508 patients (mean±SD age, 75±11 years) with MAS (aortic valve area between 1 and 1.5 cm²; mean±SD aortic valve area, 1.2±0.15 cm²) and preserved left ventricular ejection fraction. Patients were mostly (86.4%) asymptomatic or minimally symptomatic, 78.3% had hypertension, 36.2% were diabetics, and 48.3% had dyslipidemia. Each patient with MAS was matched for the average survival (per year) of all patients of the same age and same sex from our region (Somme department, north of France). During follow‐up (median 47 months), 113 patients (22.2%) underwent aortic valve replacement for severe AS. The mean±SD time between inclusion and surgery was 37±22 months. During follow‐up, 255 patients (50.2%) died. The 6‐year survival of patients with MAS was lower than the expected survival (53±2% versus 65%). In multivariate analysis, age (hazard ratio, 1.04 [95% CI, 1.02–1.05]; P<0.001), prior atrial fibrillation (hazard ratio, 1.35 [95% CI, 1.05–1.73]; P=0.019), and Charlson comorbidity index (hazard ratio, 1.11 [95% CI, 1.05–1.18]; P=0.002) were associated with increased mortality. Aortic valve replacement was associated with better survival (hazard ratio, 0.38 [95% CI, 0.27–0.54]; P<0.001).

Conclusions

The results of this study show that patients with MAS present many cardiovascular risk factors, a high rate of surgery during follow‐up, and increased mortality compared with the general population mainly related to associated comorbidities. Patients with MAS should, therefore, be managed for their cardiovascular risk factors and comorbidities. They require close follow‐up, especially when the aortic valve area is close to 1 cm², as aortic valve replacement performed when patients transition to severe AS and develop indications for surgery during follow‐up is associated with better survival.

Aortic valve microcalcification and cardiovascular risk: an exploratory study using sodium fluoride in high cardiovascular risk patients

18F-sodium fluoride (18F-NaF) has been used to access aortic stenosis in clinical research setting. It is known that its uptake is related with microcalcification. The purpose of this study was to assess the relationship between 18F-NaF uptake by the aortic valve and cardiovascular risk. Twenty-five patients with risk factors for cardiovascular disease, without known cardiovascular disease or aortic stenosis underwent PET-CT with 18F-NaF. Cardiovascular risk was assessed through the ASCVD (Atherosclerotic Cardiovascular Disease) risk calculator. Aortic valve 18F-NaF (AoVCUL) uptake was evaluated through the corrected uptake per lesion (CUL = max SUV - mean blood-pool SUV). Calcium score was obtained through cardiac CT. The patients present a mean age of 63.90 ± 8.60 years and 56% males. The mean ASCVD was of 28.76 ± 18.96 (M 25, IQR 38.50). The mean aortic valve calcium score (AoVCaSc) was of 53.24 ± 164.38 (M 6; IQR 29.75) and the AoVCUL was of 0.50 ± 0.10 (M 0.52, IQR 0.15). The patients were classified according to the ASCVD: patients with a risk greater or equal than the 50th percentile of the ASCVD risk and patients with a risk lower than the 50th percentile. The AoVCUL was evaluated in both groups: AoVCUL = 0.56 ± 0.10 vs 0.42 ± 0.15, p = 0.02; AoVCaSc was of 0 in 11 patients (44%) and those with an ASCVD greater or equal than the 50th percentile had a mean AoVCaSc of 8.00 ± 13.80, and those with an ASCVD risk lower than the 50th percentile had a mean AoVCaSc of 95.00 ± 223.45; p = 0.09. In this study microcalcification, evaluated through 18F-NaF on PET-CT, was related with cardiovascular risk. Although the score of calcium seems to be higher in higher cardiovascular risk patients, no significant difference was found between groups.

Porphyrin-Based SOD Mimic MnTnBu OE -2-PyP5+ Inhibits Mechanisms of Aortic Valve Remodeling in Human and Murine Models of Aortic Valve Sclerosis

Background

Aortic valve sclerosis (AVSc), the early asymptomatic presentation of calcific aortic valve (AV) disease, affects 25% to 30% of patients aged >65 years. In vitro and ex vivo experiments with antioxidant strategies and antagonists of osteogenic differentiation revealed that AVSc is reversible. In this study, we characterized the underlying changes in the extracellular matrix architecture and valve interstitial cell activation in AVSc and tested in vitro and in vivo the activity of a clinically approved SOD (superoxide dismutase) mimic and redox‐active drug MnTnBuOE‐2‐PyP⁵⁺ (BMX‐001).

Methods and Results

After receiving informed consent, samples from patients with AVSc, AV stenosis, and controls were collected. Uniaxial mechanical stimulation and in vitro studies on human valve interstitial cells were performed. An angiotensin II chronic infusion model was used to impose AV thickening and remodeling. We characterized extracellular matrix structures by small‐angle light scattering, scanning electron microscopy, histology, and mass spectrometry. Diseased human valves showed altered collagen fiber alignment and ultrastructural changes in AVSc, accumulation of oxidized cross‐linking products in AV stenosis, and reversible expression of extracellular matrix regulators ex vivo. We demonstrated that MnTnBuOE‐2‐PyP⁵⁺ inhibits human valve interstitial cell activation and extracellular matrix remodeling in a murine model (C57BL/6J) of AVSc by electron microscopy and histology.

Conclusions

AVSc is associated with architectural remodeling despite marginal effects on the mechanical properties in both human and mice. MnTnBuOE‐2‐PyP⁵⁺ controls AV thickening in a murine model of AVSc. Because this compound has been approved recently for clinical use, this work could shift the focus for the treatment of calcific AV disease, moving from AV stenosis to an earlier presentation (AVSc) that could be more responsive to medical therapies.

Aortic Valve Sclerosis Adds to Prediction of Short-Term Mortality in Patients with Documented Coronary Atherosclerosis

Aims: Aortic valve sclerosis (AVSc), a non-uniform thickening of leaflets with an unrestricted opening, is characterized by inflammation, lipoprotein deposition, and matrix degradation. In the general population, AVSc predicts long-term cardiovascular mortality (+50%) even after adjustment for vascular risk factors and clinical atherosclerosis. We have hypothesized that AVSc is a risk-multiplier able to predict even short-term mortality. To address this issue, we retrospectively analyzed 90-day mortality of all patients who underwent isolated coronary artery bypass grafting (CABG) at Centro Cardiologico Monzino over a ten-year period (2006–2016). Methods: We analyzed 2246 patients and 90-day all-cause mortality was 1.5% (31 deaths). We selected only patients deceased from cardiac causes (n = 29) and compared to alive patients (n = 2215). A cardiologist classified the aortic valve as no-AVSc (n = 1352) or AVSc (n = 892). Cox linear regression and integrated discrimination improvement (IDI) analyses were used to evaluate AVSc in predicting 90-day mortality. Results: AVSc 90-day survival (97.6%) was lower than in no-AVSc (99.4%; p < 0.0001) with a hazard ratio (HR) of 4.0 (95%CI: 1.78, 9.05; p < 0.0001). The HR for AVSc, adjusted for propensity score, was 2.7 (95%CI: 1.17, 6.23; p = 0.02) and IDI statistics confirmed that AVSc significantly adds (p < 0.001) to the identification of high-risk patients than EuroSCORE II alone. Conclusion: Our data supports the hypothesis that a risk stratification strategy based on AVSc, added to ESII, may allow better recognition of patients at high-risk of short-term mortality after isolated surgical myocardial revascularization. Results from this study warrant further confirmation.

Cardiovascular morbidity and mortality in patients with aortic valve sclerosis: A systematic review and meta-analysis

AIMS

The association between aortic valve sclerosis (AVSc) and cardiovascular (CV) events is not consistent among different studies. We have performed a meta-analysis evaluating the association between AVSc and fatal and/or non-fatal CV and cerebrovascular events.

METHODS AND RESULTS

A systematic search was performed in the electronic databases (PubMed, Web of Science, Scopus, EMBASE). Studies evaluating coronary artery disease (CAD), stroke and CV mortality in AVSc patients and controls were included. Differences among cases and controls were expressed as Odds Ratio (OR) with pertinent 95% Confidence Intervals (CI). Thirty-one studies on 10,537 AVSc patients and 25,005 controls were included in the final analysis. The absolute risk of CAD was 45.8% (95% CI: 32.9-59.3) in AVSc patients and 29.4% (95% CI: 21.8-38.5) in controls with an OR of 2.02 (95% CI: 1.67-2.44) and an attributable risk of 35.8%. Moreover, stroke was reported in 11.8% (95% CI: 4.4-27.7) of AVSc patients and 7.9% (95% CI: 2.5-22.7) of controls (OR: 1.41, 95% CI: 1.16-1.71) with an attributable risk of 33.0%. CV mortality was 6.2% (95% CI: 2.7-13.5) in AVSc patients and 2.0% (95% CI: 0.5-7.9) in controls (OR: 2.70, 95% CI: 1.45-5.01), with an attributable risk of 67.7%. Results were confirmed when pooling together ORs for CAD, stroke and CV mortality obtained by means of multivariate analysis.

CONCLUSIONS

AVSc is associated with CAD, stroke and CV mortality. Taken together, these data suggest that patients with AVSc may benefit from a stricter CV risk monitoring and that AVSc screening may be included in the frame of CV risk stratification protocols.

Which prognostic factors should be used in pulmonary arterial hypertension in elderly patients?

In recent times, the prevalence of pulmonary arterial hypertension (PAH) is more commonly seen among elderly populations. The increased prevalence of hypertension, diabetes, obesity, arterial stiffness, as well as diastolic dysfunction, may cause endothelial dysfunction and affect pulmonary vasculature. Furthermore, older patients have certain differences in clinical characteristics and outcomes. In this article, the special characteristics of aging in PAH patients have been reviewed, while the risk predictors of elderly patients are also discussed.

Heart Valve Biomechanics and Underlying Mechanobiology

Heart valves control unidirectional blood flow within the heart during the cardiac cycle. They have a remarkable ability to withstand the demanding mechanical environment of the heart, achieving lifetime durability by processes involving the ongoing remodeling of the extracellular matrix. The focus of this review is on heart valve functional physiology, with insights into the link between disease-induced alterations in valve geometry, tissue stress, and the subsequent cell mechanobiological responses and tissue remodeling. We begin with an overview of the fundamentals of heart valve physiology and the characteristics and functions of valve interstitial cells (VICs). We then provide an overview of current experimental and computational approaches that connect VIC mechanobiological response to organ- and tissue-level deformations and improve our understanding of the underlying functional physiology of heart valves. We conclude with a summary of future trends and offer an outlook for the future of heart valve mechanobiology, specifically, multiscale modeling approaches, and the potential directions and possible challenges of research development. © 2016 American Physiological Society. Compr Physiol 6:1743-1780, 2016.

Markers of subclinical atherosclerosis in patients with aortic valve sclerosis: A meta-analysis of literature studies

OBJECTIVE

Growing evidence suggested an association between aortic valve sclerosis (AVSc) and cardiovascular (CV) events. However, little is known about the association of AVSc with major markers of subclinical atherosclerosis. We performed a meta-analysis of literature studies to address this issue.

METHODS

Studies on the relationship between AVSc and common carotid artery intima-media thickness (IMT), prevalence of carotid plaques (CPs), flow-mediated dilation (FMD), aortic pulse wave velocity (PWV) and augmentation index (AIx) were systematically searched in electronic databases. Thirteen studies enrolling 1086 AVSc patients and 2124 controls were included.

RESULTS

Compared to controls, AVSc patients showed higher IMT (MD: 0.32mm; 95%CI: 0.07, 0.58; p=0.014), and higher prevalence of CPs (OR: 4.06; 95%CI: 2.38, 6.93; p<0.001). Moreover, lower FMD (MD: -4.48%; 95%CI: -7.23, -1.74; p=0.001) and higher PWV (MD: 0.96%; 95%CI: 0.11, 1.81; p=0.027) were found in AVSc subjects than in controls, with no differences in AIx (MD: 0.76%; 95%CI: -0.97, 2.49; p=0.389). In meta-regression analyses, body mass index and triglyceride levels have an impact on the difference in IMT between cases and controls, while male gender and smoking habit were associated with the difference in the prevalence of CPs between the two groups.

CONCLUSIONS

AVSc is significantly associated with altered markers of subclinical atherosclerosis, thus supporting the concept that AVSc and atherosclerosis share common etiopathological mechanism and/or risk factors.

Aortic valve sclerosis as a marker of atherosclerosis: Novel insights from hepatic steatosis

BACKGROUND

Nowadays, aortic valve sclerosis (AVSc) might be considered an atherosclerosis-like process due to significant association with age, male gender and some major features of metabolic syndrome. Nonalcoholic fatty liver disease (NAFLD) has been recognized as a clinical expression of the metabolic syndrome and as a predictor of cardiovascular events. We aim, with this meta-analysis, to evaluate the correlation between NAFLD and AVSc; this finding might suggest new insights and interactions among NAFLD, AVSc and the atherosclerotic process.

METHODS AND RESULTS

A detailed search was conducted according to Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines to identify all studies providing data about the association between AVSc and NAFLD. 3 studies enrolling a total of 1172 patients with NAFLD and 1467 controls without NAFLD were included in the meta-analysis. The prevalence of AVSc was 41.3% (95% CI: 32.0%, 51.4%) in NAFLD patients and 24.6% (18.4%, 32.0%) in subjects without NAFLD with a corresponding OR of 2.28 (95% CI: 1.21, 4.28, p=0.01, I(2): 77.6%, p=0.011). A meta-regression analysis showed that age, prevalence of male gender, hypertension, body mass index, and dyslipidemia were directly and significantly associated with the difference in the prevalence of AVSc between patients with NAFLD and those without.

CONCLUSIONS

In conclusion, our meta-analysis shows a significant association between NAFLD and AVSc. However, further evidence is needed to validate these findings and find out if there is a real link or just a mere association.

Regeneration ability of valvular interstitial cells from diseased heart valve leaflets

Valvular interstitial cells from diseased aortic valve leaflets show their ability to regenerate–to proliferate and grow, to express appropriate genes and to deposit suitable proteins–in a non-degenerative nanofibrous substrate.

Coupled Simulation of Heart Valves: Applications to Clinical Practice

The last few decades have seen great advances in the understanding of heart valves, and consequently, in the development of novel treatment modalities and surgical procedures for valves afflicted by disease. This is due in part to the profound advancements in computing technology and noninvasive medical imaging techniques that have made it possible to numerically model the complex heart valve systems characterized by distinct features at different length scales and various interacting processes. In this article, we highlight the importance of explicitly coupling these multiple scales and diverse processes to accurately simulate the true behavior of the heart valves, in health and disease. We examine some of the computational modeling studies that have a direct consequence on clinical practice.

Cardiac valve cells and their microenvironment--insights from in vitro studies

During every heartbeat, cardiac valves open and close coordinately to control the unidirectional flow of blood. In this dynamically challenging environment, resident valve cells actively maintain homeostasis, but the signalling between cells and their microenvironment is complex. When homeostasis is disrupted and the valve opening obstructed, haemodynamic profiles can be altered and lead to impaired cardiac function. Currently, late stages of cardiac valve diseases are treated surgically, because no drug therapies exist to reverse or halt disease progression. Consequently, investigators have sought to understand the molecular and cellular mechanisms of valvular diseases using in vitro cell culture systems and biomaterial scaffolds that can mimic the extracellular microenvironment. In this Review, we describe how signals in the extracellular matrix regulate valve cell function. We propose that the cellular context is a critical factor when studying the molecular basis of valvular diseases in vitro, and one should consider how the surrounding matrix might influence cell signalling and functional outcomes in the valve. Investigators need to build a systems-level understanding of the complex signalling network involved in valve regulation, to facilitate drug target identification and promote in situ or ex vivo heart valve regeneration.

Osteopontin-CD44v6 interaction mediates calcium deposition via phospho-Akt in valve interstitial cells from patients with noncalcified aortic valve sclerosis

OBJECTIVE

The activation of valve interstitial cells (VICs) toward an osteogenic phenotype characterizes aortic valve sclerosis, the early asymptomatic phase of calcific aortic valve disease. Osteopontin is a phosphorylated acidic glycoprotein that accumulates within the aortic leaflets and labels VIC activation even in noncalcified asymptomatic patients. Despite this, osteopontin protects VICs against in vitro calcification. Here, we hypothesize that the specific interaction of osteopontin with CD44v6, and the related intracellular pathway, prevents calcium deposition in human-derived VICs from patients with aortic valve sclerosis.

APPROACH AND RESULTS

On informed consent, 23 patients and 4 controls were enrolled through the cardiac surgery and heart transplant programs. Human aortic valves and VICs were tested for osteogenic transdifferentiation, ex vivo and in vitro. Osteopontin-CD44 interaction was analyzed using proximity ligation assay and the signaling pathways investigated. A murine model based on angiotensin II infusion was used to mimic early pathological remodeling of the aortic valves. We report osteopontin-CD44 functional interaction as a hallmark of early stages of calcific aortic valve disease. We demonstrated that osteopontin-CD44 interaction mediates calcium deposition via phospho-Akt in VICs from patients with noncalcified aortic valve sclerosis. Finally, microdissection analysis of murine valves shows increased cusp thickness in angiotensin II-treated mice versus saline infused along with colocalization of osteopontin and CD44 as seen in human lesions.

CONCLUSIONS

Here, we unveil a specific protein-protein association and intracellular signaling mechanisms of osteopontin. Understanding the molecular mechanisms of early VIC activation and calcium deposition in asymptomatic stage of calcific aortic valve disease could open new prospective for diagnosis and therapeutic intervention.

The prevalence, incidence, progression, and risks of aortic valve sclerosis: a systematic review and meta-analysis

OBJECTIVES

The aim of this study was to comprehensively review the epidemiology of aortic sclerosis (ASc) and its association with cardiovascular events.

BACKGROUND

ASc, which is defined as thickening or calcification of the aortic valve without significant obstruction of blood flow, is a common finding on cardiac imaging.

METHODS

We searched MEDLINE and EMBASE from inception to April 2013 for studies describing the epidemiology of ASc and performed a meta-analysis of the risk of adverse events using a random effects model.

RESULTS

Twenty-two studies were identified from the systematic review. The prevalence of ASc increased in proportion to the average age of study participants, ranging from 9% in a study in which the mean age was 54 years to 42% in a study in which the mean age was 81 years. In total, 1.8% to 1.9% of participants with ASc had progression to clinical aortic stenosis per year. There was a 68% increased risk of coronary events in subjects with ASc (hazard ratio [HR]: 1.68; 95% confidence interval [CI]: 1.31 to 2.15), a 27% increased risk of stroke (HR: 1.27; 95% CI: 1.01 to 1.60), a 69% increased risk of cardiovascular mortality (HR: 1.69; 95% CI: 1.32 to 2.15), and a 36% increased risk of all-cause mortality (HR: 1.36; 95% CI: 1.17 to 1.59).

CONCLUSIONS

ASc is a common finding that is more prevalent with older age. Despite low rates of progression to ASc, there is an independent increase in morbidity and mortality associated with the condition.

Mitral and aortic valve sclerosis/calcification and carotid atherosclerosis: results from 1065 patients

This study assesses whether aortic valve sclerosis (AVS) and mitral annulus calcification (MAC) are associated with carotid artery atherosclerosis, independently of traditional cardiovascular risk factors. A total of 1065 patients underwent both echocardiography and carotid artery ultrasound scanning. AVS and MAC were defined as focal areas of increased echogenicity and thickening of the aortic leaflets or mitral valve annulus. Carotid artery atherosclerosis was defined as presence/absence of any atherosclerotic plaque or presence/absence of plaque >50 %. Of 1065 patients (65 ± 9 years; 38 % female) who comprised the study population, 642 (60 %) had at least one atherosclerotic plaque. AVS, but not mitral valve sclerosis; was associated with the presence of carotid atherosclerosis (odds ratio (OR) 1.9, 95 % confidence interval (CI) 1.2-3.9; P = 0.005) and the degree of carotid atherosclerosis (OR 2.1, 95 % CI 1.2-3.9; P = 0.01) in a multivariate model including age, gender, previous ischemic heart disease, hypertension, dyslipidemia, smoking, diabetes, family cardiovascular history, left ventricular size, mass, and ejection fraction, and left atrial size. AVS is a significant predictor of carotid atherosclerosis, independently of other cardiovascular clinical and echocardiographic risk factors.

Noggin attenuates the osteogenic activation of human valve interstitial cells in aortic valve sclerosis

AIMS

Aortic valve sclerosis (AVSc) is a hallmark of several cardiovascular conditions ranging from chronic heart failure and myocardial infarction to calcific aortic valve stenosis (AVS). AVSc, present in 25-30% of patients over 65 years of age, is characterized by thickening of the leaflets with marginal effects on the mechanical proprieties of the valve making its presentation asymptomatic. Despite its clinical prevalence, few studies have investigated the pathogenesis of this disease using human AVSc specimens. Here, we investigate in vitro and ex vivo BMP4-mediated transdifferentiation of human valve interstitial cells (VICs) towards an osteogenic-like phenotype in AVSc.

METHODS AND RESULTS

Human specimens from 60 patients were collected at the time of aortic valve replacement (AVS) or through the heart transplant programme (Controls and AVSc). We show that non-calcified leaflets from AVSc patients can be induced to express markers of osteogenic transdifferentiation and biomineralization through the combinatory effect of BMP4 and mechanical stimulation. We show that BMP4 antagonist Noggin attenuates VIC activation and biomineralization. Additionally, patient-derived VICs were induced to transdifferentiate using either cell culture or a Tissue Engineering (TE) Aortic Valve model. We determine that while BMP4 alone is not sufficient to induce osteogenic transdifferentiation of AVSc-derived cells, the combinatory effect of BMP4 and mechanical stretch induces VIC activation towards a phenotype typical of late calcified stage of the disease.

CONCLUSION

This work demonstrates, for the first time using AVSc specimens, that human sclerotic aortic valves can be induced to express marker of osteogenic-like phenotype typical of advanced severe aortic stenosis.

Antioxidant enzymes reduce DNA damage and early activation of valvular interstitial cells in aortic valve sclerosis

OBJECTIVE

Accumulation of reactive oxygen species (ROS) and remodeling of the microstructure of the cusp characterize aortic valve sclerosis, the early phase of calcific aortic valve disease. These events are associated with activation of valvular interstitial cells (VICs) toward an osteogenic-like phenotype. Because ROS cause DNA damage and transcriptional activation we investigated the relationship between ROS, DNA damage response, and transdifferentiation of VICs.

METHODS AND RESULTS

Human aortic valve cusps and patient-matched VICs were collected from 39 patients both with and without calcific aortic valve disease. VICs were exposed to hydrogen peroxide (0.1-1 mmol/L) after cell transduction with extracellular superoxide dismutase/catalase adenoviruses and characterized for DNA-damage response, osteogenic transdifferentiation, and calcification. ROS induce relocalization of phosphorylated γH2AX, MRE11, and XRCC1 proteins with expression of osteogenic signaling molecule RUNX2 via AKT. We report a sustained activation of γH2AX in aortic valve sclerosis-derived VICs suggesting their impaired ability to repair DNA damage. Adenovirus superoxide dismutase/catalase transduction decreases ROS-induced DNA damage and VIC transdifferentiation in aortic valve sclerosis-derived cells. Finally, adenoviral transduction with catalase reverts ROS-mediated calcification and cellular transdifferentiation.

CONCLUSIONS

We conclude that the ROS-induced DNA damage response is dysfunctional in early asymptomatic stages of calcific aortic valve disease. We unveiled an association among ROS, DNA-damage response, and cellular transdifferentiation, reversible by antioxidant enzymes delivery.

Aortic and mitral annular calcifications are predictive of all-cause and cardiovascular mortality in patients with type 2 diabetes

OBJECTIVE

To examine the association of aortic valve sclerosis (AVS) and mitral annulus calcification (MAC) with all-cause and cardiovascular mortality in type 2 diabetic individuals.

RESEARCH DESIGN AND METHODS

We retrospectively analyzed the data from 902 type 2 diabetic outpatients, who had undergone a transthoracic echocardiography for clinical reasons during the years 1992-2007. AVS and MAC were diagnosed by echocardiography, and a heart valve calcium (HVC) score was calculated by summing up the AVS and MAC variables. The study outcomes were all-cause and cardiovascular mortality.

RESULTS

At baseline, 477 (52.9%) patients had no heart valves affected (HVC-0), 304 (33.7%) had one valve affected (HVC-1), and 121 (13.4%) had both valves affected (HVC-2). During a mean follow-up of 9 years, 137 (15.2%) patients died, 78 of them from cardiovascular causes. Compared with patients with HVC-0, those with HVC-2 had the highest risk of all-cause and cardiovascular mortality, whereas those with HVC-1 had an intermediate risk (P < 0.0001 by the log-rank test). After adjustment for sex, age, BMI, systolic blood pressure, diabetes duration, A1C, LDL cholesterol, estimated glomerular filtration rate, smoking, history of myocardial infarction, and use of antihypertensive and lipid-lowering drugs, the hazard ratio of all-cause mortality was 2.3 (95% CI 1.1-4.9; P < 0.01) for patients with HVC-1 and 9.3 (3.9-17.4; P < 0.001) for those with HVC-2. Similar results were found for cardiovascular mortality.

CONCLUSIONS

Our findings indicate that AVS and MAC, singly or in combination, are independently associated with all-cause and cardiovascular mortality in type 2 diabetic patients.