Calcific aortic stenosis--time to look more closely at the valve

Sex-dependent expression of galectin-1, a cardioprotective β-galactoside-binding lectin, in human calcific aortic stenosis

We aimed to analyze sex-related differences in galectin-1 (Gal-1), a β-galactoside-binding lectin, in aortic stenosis (AS) and its association with the inflammatory and fibrocalcific progression of AS. Gal-1 was determined in serum and aortic valves (AVs) from control and AS donors by western blot and immunohistochemistry. Differences were validated by ELISA and qPCR in AS samples. In vitro experiments were conducted in primary cultured valve interstitial cells (VICs). Serum Gal-1 was not different neither between control and AS nor between men and women. There was no association between circulating and valvular Gal-1 levels. The expression of Gal-1 in stenotic AVs was higher in men than women, even after adjusting for confounding factors, and was associated with inflammation, oxidative stress, extracellular matrix remodeling, fibrosis, and osteogenesis. Gal-1 (LGALS1) mRNA was enhanced within fibrocalcific areas of stenotic AVs, especially in men. Secretion of Gal-1 was up-regulated over a time course of 2, 4, and 8 days in men's calcifying VICs, only peaking at day 4 in women's VICs. In vitro, Gal-1 was associated with similar mechanisms to those in our clinical cohort. β-estradiol significantly up-regulated the activity of an LGALS1 promoter vector and the secretion of Gal-1, only in women's VICs. Supplementation with rGal-1 prevented the effects elicited by calcific challenge including the metabolic shift to glycolysis. In conclusion, Gal-1 is up-regulated in stenotic AVs and VICs from men in association with inflammation, oxidative stress, matrix remodeling, and osteogenesis. Estrogens can regulate Gal-1 expression with potential implications in post-menopause women. Exogenous rGal-1 can diminish calcific phenotypes in both women and men.

Clinical Implication of Consistently Strict Phosphate Control for Coronary and Valvular Calcification in Incident Patients Undergoing Hemodialysis

AIMS

Serum phosphate control is crucial for the progression of vascular and valvular calcifications. Strict phosphate control is recently suggested; however, there is a lack of convincing evidence. Therefore, we explored the effects of strict phosphate control on vascular and valvular calcifications in incident patients undergoing hemodialysis.

METHODS

A total of 64 patients undergoing hemodialysis from our previous randomized controlled trial were included in this study. Coronary artery calcification score (CACS) and cardiac valvular calcification score (CVCS) were evaluated using computed tomography and ultrasound cardiography at baseline and 18 months after the initiation of hemodialysis. The absolute changes in CACS (ΔCACS) and CVCS (ΔCVCS) and the percent change in CACS (%ΔCACS) and CVCS (%ΔCVCS) were calculated. Serum phosphate level was measured at 6, 12, and 18 months after the initiation of hemodialysis. Moreover, phosphate control status was evaluated using the area under the curve (AUC) by the amount of time spent with a serum phosphate level of ≥ 4.5 mg/dL and the extent to which this threshold exceeded over the observation period.

RESULTS

ΔCACS, %ΔCACS, ΔCVCS, and %ΔCVCS were significantly lower in the low AUC group than in the high AUC group. ΔCACS and %ΔCACS were also significantly lower. ΔCVCS and %ΔCVCS tended to be lower in patients whose serum phosphate level never exceeded 4.5 mg/dL than in those whose serum phosphate level continuously exceeded 4.5 mg/dL. AUC significantly correlated with ΔCACS and ΔCVCS.

CONCLUSION

Consistently strict phosphate control may slow the progression of coronary and valvular calcifications in incident patients undergoing hemodialysis.

Sex discrepancies in pathophysiology, presentation, treatment, and outcomes of severe aortic stenosis

This review gives an overview of sex-based differences in aortic valve stenosis, spanning from pathophysiological mechanisms and disease progression, clinical presentation, presence of comorbidities, and diagnostic assessment, to treatment and outcomes. In particular, sex-related differences in the degree of aortic valve calcification, the response of the left ventricle to pressure overload, as well as in the referral to procedures, with women being less frequently referred for surgical aortic valve replacement and experiencing longer waiting times for transcatheter procedures, will be discussed. Sex-related differences are also particularly evident in outcomes of patients with severe aortic stenosis undergoing surgical or transcatheter procedures. The apparent sex paradox seen in women undergoing transcatheter aortic valve implantation refers to the phenomenon of women experiencing higher rates of short-term mortality and bleeding events, but demonstrating improved long-term survival as compared to men. Women who undergo surgical aortic valve replacement have generally worse outcomes as compared to men, which is reflected by the inclusion of female sex in surgical risk calculation scores. Hence, a thorough understanding of sex-related differences in aortic valve stenosis is important to provide optimal and personalized patient care.

Percutaneous Coronary Intervention and Discretionary Atherectomy in Patients with Aortic Stenosis: 2016-2019 National Inpatient Sample

BACKGROUND

Patients with aortic stenosis (AS) usually have concomitant calcified coronary artery disease (CAD) requiring atherectomy to improve lesion compliance and odds of successful percutaneous coronary intervention (PCI). However, there is a paucity of data regarding PCI with or without atherectomy in patients with AS.

METHODS

The National Inpatient Sample (NIS) database was queried from 2016 through 2019 using ICD-10 codes to identify individuals with AS who underwent PCI with or without atherectomy (Orbital Atherectomy [OA], Rotational or Laser Atherectomy [non-OA]). Temporal trends, safety, outcomes, costs, and correlates of major adverse cardiovascular events (MACE) were assessed using discharge weighted data.

RESULTS

Hospitalizations of 45,420 AS patients undergoing PCI with or without atherectomy were identified and of those, 88.6 %, 2.3 %, and 9.1 % were treated with PCI-only, OA, or non-OA, respectively. There was an increase in PCIs (8855 to 10,885), atherectomy [OA (165 to 300) and non-OA (795 to 1255)], and intravascular ultrasound (IVUS) use (625 to 1000). The median cost of admission was higher in the atherectomy cohorts ($34,340.77 in OA, $32,306.2 in non-OA) as compared to the PCI-only cohort ($23,683.98). Patients tend to have decreased odds of MACE with IVUS guided atherectomy and PCI.

CONCLUSIONS

This large database revealed a significant increase in PCI with or without atherectomy in AS patients from 2016 to 2019. Considering the complex comorbidities of AS patients, the overall complication rates were well distributed among the different cohorts, suggesting that IVUS guided PCI with or without atherectomy in patients with AS is feasible and safe.

Aortic stenosis: a review on acquired pathogenesis and ominous combination with diabetes mellitus

BACKGROUND

Aortic stenosis (AS) is a progressive disease, with no pharmacological treatment. The prevalence of diabetes mellitus (DM) among AS patients is higher than in the general population. DM significantly increases the risk of AS development and progression from mild to severe. The interplay between AS and DM's mechanism is not entirely known yet.

MAIN BODY

The increased accumulation of advanced glycation end products (AGEs) was linked to increased valvular oxidative stress, inflammation, expression of coagulation factors, and signs of calcification, according to an analysis of aortic stenotic valves. It is interesting to note that in diabetic AS patients, valvular inflammation did not correlate with serum glucose levels but rather only with long-term glycemic management markers like glycated haemoglobin and fructosamine. Transcatheter aortic valve replacement, which has been shown to be safer than surgical aortic valve replacement, is advantageous for AS patients who also have concurrent diabetes. Additionally, novel anti-diabetic medications have been proposed to lower the risk of AS development in DM patients, including sodium-glucose cotransporter-2 inhibitors and glucagon-like peptide-1 receptor agonist that target reduction of AGEs-mediated oxidative stress.

CONCLUSIONS

There are little data on the effects of hyperglycemia on valvular calcification, but understanding the interactions between them is essential to develop a successful treatment strategy to stop or at least slow the progression of AS in DM patients. There is a link among AS and DM and that DM negatively impacts the quality of life and longevity of AS patients. The sole successful treatment, despite ongoing efforts to find new therapeutic modalities, involves aortic valve replacement. More research is required to find methods that can slow the advancement of these conditions, enhancing the prognosis and course of people with AS and DM.

A Straightforward Cytometry-Based Protocol for the Comprehensive Analysis of the Inflammatory Valve Infiltrate in Aortic Stenosis

Aortic stenosis (AS) is a frequent cardiac disease in old individuals, characterized by valvular calcification, fibrosis, and inflammation. Recent studies suggest that AS is an active inflammatory atherosclerotic-like process. Particularly, it has been suggested that several immune cell types, present in the valve infiltrate, contribute to its degeneration and to the progression toward stenosis. Furthermore, the infiltrating T cell subpopulations mainly consist of oligoclonal expansions, probably specific for persistent antigens. Thus, the characterization of the cells implicated in the aortic valve calcification and the analysis of the antigens to which those cells respond to is of utmost importance to develop new therapies alternative to the replacement of the valve itself. However, calcified aortic valves have been only studied so far by histological and immunohistochemical methods, unable to render an in-depth phenotypical and functional cell profiling. Here we present, for the first time, a simple and efficient cytometry-based protocol that allows the identification and quantification of infiltrating inflammatory leukocytes in aortic valve explants. Our cytometry protocol saves time and facilitates the simultaneous analysis of numerous surface and intracellular cell markers and may well be also applied to the study of other cardiac diseases with an inflammatory component.

Left Atrial Remodeling in Response to Aortic Valve Replacement: Pathophysiology and Myocardial Strain Analysis

Severe aortic stenosis (AS) is the most common valve disease in the elderly and is associated with poor prognosis if treated only medically. AS causes chronic pressure overload, concentric left ventricular (LV) hypertrophy, myocardial stiffness, and diastolic dysfunction. This adverse remodeling also affects the left atrium (LA), which dilates and develops myocardial fibrosis, with a reduction in intrinsic function and a consequent high risk of the development of atrial fibrillation. Speckle-tracking echocardiography is able to detect myocardial dysfunction before other conventional parameters, such as LV ejection fraction, and also predict clinical outcomes. This review aims at describing LV and LA remodeling in AS and before and after aortic valve replacement and the usefulness of myocardial strain analysis in this clinical setting.

Perioperative management of P2Y12 inhibitors in patients undergoing cardiac surgery within 1 year of PCI

AIMS

To evaluate the impact of perioperative P2Y12 receptor inhibitor therapy among patients undergoing cardiac surgery within 1 year of percutaneous coronary intervention (PCI).

METHODS AND RESULTS

Patients undergoing cardiac surgery in the year post-PCI at three tertiary care centres between 2011 and 2018 were stratified into those who had received at least one dose of P2Y12 inhibitor prior to surgery (within 5 days for clopidogrel or prasugrel, or within 3 days for ticagrelor) and those who had not. The outcomes of interest were major adverse cardiac and cerebrovascular events (MACCEs) and bleeding. Among 20 279 PCI patients, 359 (1.8%) underwent cardiac surgery in the ensuing year, 76.3% of whom received coronary artery bypass grafts. Overall, 33 (9.2%) MACCEs and 85 (23.7%) bleeding events occurred within 30 days post-cardiac surgery. Perioperative P2Y12 inhibition (N = 133, 37%) was not associated with the risk of MACCEs or bleeding, despite numerically lower rates of myocardial infarction or stent thrombosis (0.0% vs. 2.6%; P = 0.089). Patients who continued the P2Y12 inhibitor until the day of surgery (N = 60, 17%) had significantly higher bleeding risk [adjusted odds ratio 2.93, 95% confidence interval 1.53-5.59)]. Predictors of MACCEs included a time interval from PCI to cardiac surgery of ≤30 days and reduced ejection fraction, whereas urgent/emergent surgery predicted bleeding. Chronic kidney disease and myocardial infarction as indication for PCI predicted both MACCEs and bleeding.

CONCLUSION

Among patients undergoing cardiac surgery in the year after PCI, the perioperative risk of ischaemic and bleeding events might be influenced by P2Y12 inhibitor therapy in addition to other risk parameters, including the timing and urgency of the procedure.

Direct proteomic and high-resolution microscopy biopsy analysis identifies distinct ventricular fates in severe aortic stenosis

The incidence of aortic valve stenosis (AS), the most common reason for aortic valve replacement (AVR), increases with population ageing. While untreated AS is associated with high mortality, different hemodynamic subtypes range from normal left-ventricular function to severe heart failure. However, the molecular nature underlying four different AS subclasses, suggesting vastly different myocardial fates, is unknown. Here, we used direct proteomic analysis of small left-ventricular biopsies to identify unique protein expression profiles and subtype-specific AS mechanisms. Left-ventricular endomyocardial biopsies were harvested from patients during transcatheter AVR, and inclusion criteria were based on echocardiographic diagnosis of severe AS and guideline-defined AS-subtype classification: 1) normal ejection fraction (EF)/high-gradient; 2) low EF/high-gradient; 3) low EF/low-gradient; and 4) paradoxical low-flow/low-gradient AS. Samples from non-failing donor hearts served as control. We analyzed 25 individual left-ventricular biopsies by data-independent acquisition mass spectrometry (DIA-MS), and 26 biopsies by histomorphology and cardiomyocytes by STimulated Emission Depletion (STED) superresolution microscopy. Notably, DIA-MS reliably detected 2273 proteins throughout each individual left-ventricular biopsy, of which 160 proteins showed significant abundance changes between AS-subtype and non-failing samples including the cardiac ryanodine receptor (RyR2). Hierarchical clustering segregated unique proteotypes that identified three hemodynamic AS-subtypes. Additionally, distinct proteotypes were linked with AS-subtype specific differences in cardiomyocyte hypertrophy. Furthermore, superresolution microscopy of immunolabeled biopsy sections showed subcellular RyR2-cluster fragmentation and disruption of the functionally important association with transverse tubules, which occurred specifically in patients with systolic dysfunction and may hence contribute to depressed left-ventricular function in AS.

Preoperative hypomagnesemia as a possible predictive factor for postoperative increase of transvalvular pressure gradient in hemodialysis patients treated with transcatheter aortic valve implantation

BACKGROUND

Patients undergoing maintenance hemodialysis (HD) with severe aortic stenosis are at a high risk for bioprosthetic valve dysfunction after transcatheter aortic valve implantation (TAVI). Currently, preoperative factors that predict the occurrence of valve dysfunction after TAVI on HD patients remain to be elucidated. The aim of this study is to analyze the association between preoperative clinical factors and valve stenosis after TAVI on HD patients.

METHODS

Twenty-four of HD patients who underwent TAVI at our institution between April 2012 and January 2016 were analyzed. The mean aortic transvalvular pressure gradient (MPG) and effective orifice area index (EOAi) were assessed by serial echocardiography. Associations between preoperative clinical factors and time-series changes in MPG were examined using mixed-effects linear regression model for repeated measures.

RESULTS

Three patients developed severe structural valve deterioration with calcific valve stenosis requiring reoperation. A multivariate linear mixed-effects model showed that lower serum magnesium (sMg) levels were associated with the increase of MPG after TAVI (beta-coefficient = 0.019, p = 0.03). No correlation was observed with serum calcium, phosphorus, or intact parathyroid hormone. Time-series changes of MPG and EOAi had significant difference between lower and higher sMg group. All 3 of the patients who underwent reoperation showed lower preoperative sMgs.

CONCLUSION

Among bone-mineral metabolism markers, preoperative hypomagnesemia was associated with the increase of MPG after TAVI, suggesting that hypomagnesemia could predict post-TAVI valve dysfunction in HD patients. Further studies with larger sample sizes are warranted.

Development and analysis of a comprehensive diagnostic model for aortic valve calcification using machine learning methods and artificial neural networks

BACKGROUND

Although advanced surgical and interventional treatments are available for advanced aortic valve calcification (AVC) with severe clinical symptoms, early diagnosis, and intervention is critical in order to reduce calcification progression and improve patient prognosis. The aim of this study was to develop therapeutic targets for improving outcomes for patients with AVC.

MATERIALS AND METHODS

We used the public expression profiles of individuals with AVC (GSE12644 and GSE51472) to identify potential diagnostic markers. First, the R software was used to identify differentially expressed genes (DEGs) and perform functional enrichment analysis. Next, we combined bioinformatics techniques with machine learning methodologies such as random forest algorithms and support vector machines to screen for and identify diagnostic markers of AVC. Subsequently, artificial neural networks were employed to filter and model the diagnostic characteristics for AVC incidence. The diagnostic values were determined using the receiver operating characteristic (ROC) curves. Furthermore, CIBERSORT immune infiltration analysis was used to determine the expression of different immune cells in the AVC. Finally, the CMap database was used to predict candidate small compounds as prospective AVC therapeutics.

RESULTS

A total of 78 strong DEGs were identified. The leukocyte migration and pid integrin 1 pathways were highly enriched for AVC-specific DEGs. CXCL16, GPM6A, BEX2, S100A9, and SCARA5 genes were all regarded diagnostic markers for AVC. The model was effectively constructed using a molecular diagnostic score system with significant diagnostic value (AUC = 0.987) and verified using the independent dataset GSE83453 (AUC = 0.986). Immune cell infiltration research revealed that B cell naive, B cell memory, plasma cells, NK cell activated, monocytes, and macrophage M0 may be involved in the development of AVC. Additionally, all diagnostic characteristics may have varying degrees of correlation with immune cells. The most promising small molecule medicines for reversing AVC gene expression are Doxazosin and Terfenadine.

CONCLUSION

It was identified that CXCL16, GPM6A, BEX2, S100A9, and SCARA5 are potentially beneficial for diagnosing and treating AVC. A diagnostic model was constructed based on a molecular prognostic score system using machine learning. The aforementioned immune cell infiltration may have a significant influence on the development and incidence of AVC.

Chondroitin sulfate-based composites: a tour d'horizon of their biomedical applications

Chondroitin sulfate (CS), a natural anionic mucopolysaccharide, belonging to the glycosaminoglycan family, acts as the primary element of the extracellular matrix (ECM) of diverse organisms. It comprises repeating units of disaccharides possessing β-1,3-linked N-acetyl galactosamine (GalNAc), and β-1,4-linked D-glucuronic acid (GlcA), and exhibits antitumor, anti-inflammatory, anti-coagulant, anti-oxidant, and anti-thrombogenic activities. It is a naturally acquired bio-macromolecule with beneficial properties, such as biocompatibility, biodegradability, and immensely low toxicity, making it the center of attention in developing biomaterials for various biomedical applications. The authors have discussed the structure, unique properties, and extraction source of CS in the initial section of this review. Further, the current investigations on applications of CS-based composites in various biomedical fields, focusing on delivering active pharmaceutical compounds, tissue engineering, and wound healing, are discussed critically. In addition, the manuscript throws light on preclinical and clinical studies associated with CS composites. A short section on Chondroitinase ABC has also been canvassed. Finally, this review emphasizes the current challenges and prospects of CS in various biomedical fields.

Glycosaminoglycans affect endothelial to mesenchymal transformation, proliferation, and calcification in a 3D model of aortic valve disease

Calcific nodules form in the fibrosa layer of the aortic valve in calcific aortic valve disease (CAVD). Glycosaminoglycans (GAGs), which are normally found in the valve spongiosa, are located local to calcific nodules. Previous work suggests that GAGs induce endothelial to mesenchymal transformation (EndMT), a phenomenon described by endothelial cells’ loss of the endothelial markers, gaining of migratory properties, and expression of mesenchymal markers such as alpha smooth muscle actin (α-SMA). EndMT is known to play roles in valvulogenesis and may provide a source of activated fibroblast with a potential role in CAVD progression. In this study, a 3D collagen hydrogel co-culture model of the aortic valve fibrosa was created to study the role of EndMT-derived activated valvular interstitial cell behavior in CAVD progression. Porcine aortic valve interstitial cells (PAVIC) and porcine aortic valve endothelial cells (PAVEC) were cultured within collagen I hydrogels containing the GAGs chondroitin sulfate (CS) or hyaluronic acid (HA). The model was used to study alkaline phosphatase (ALP) enzyme activity, cellular proliferation and matrix invasion, protein expression, and calcific nodule formation of the resident cell populations. CS and HA were found to alter ALP activity and increase cell proliferation. CS increased the formation of calcified nodules without the addition of osteogenic culture medium. This model has applications in the improvement of bioprosthetic valves by making replacements more micro-compositionally dynamic, as well as providing a platform for testing new pharmaceutical treatments of CAVD.

Fluid-structure interaction simulation of calcified aortic valve stenosis

Calcified aortic valve stenosis (CAVS) is caused by calcium buildup and tissue thickening that impede the blood flow from left ventricle (LV) to aorta. In recent years, CAVS has become one of the most common cardiovascular diseases. Therefore, it is necessary to study the mechanics of aortic valve (AV) caused by calcification. In this paper, based on a previous idealized AV model, the hybrid immersed boundary/finite element method (IB/FE) is used to study AV dynamics and hemodynamic performance under normal and calcified conditions. The computational CAVS model is realized by dividing the AV leaflets into a calcified region and a healthy region, and each is described by a specific constitutive equation. Our results show that calcification can significantly affect AV dynamics. For example, the elasticity and mobility of the leaflets decrease due to calcification, leading to a smaller opening area with a high forward jet flow across the valve. The calcified valve also experiences an increase in local stress and strain. The increased loading due to AV stenosis further leads to a significant increase in left ventricular energy loss and transvalvular pressure gradients. The model predicted hemodynamic parameters are in general consistent with the risk classification of AV stenosis in the clinic. Therefore, mathematical models of AV with calcification have the potential to deepen our understanding of AV stenosis-induced ventricular dysfunction and facilitate the development of computational engineering-assisted medical diagnosis in AV related diseases.

The role of neutrophil elastase in aortic valve calcification

Background

Calcific aortic valve disease (CAVD) is the most commonly valvular disease in the western countries initiated by inflammation and abnormal calcium deposition. Currently, there is no clinical drug for CAVD. Neutrophil elastase (NE) plays a causal role in inflammation and participates actively in cardiovascular diseases. However, the effect of NE on valve calcification remains unclear. So we next explore whether it is involved in valve calcification and the molecular mechanisms involved.

Methods

NE expression and activity in calcific aortic valve stenosis (CAVD) patients (n = 58) and healthy patients (n = 30) were measured by enzyme-linked immunosorbent assay (ELISA), western blot and immunohistochemistry (IHC). Porcine aortic valve interstitial cells (pVICs) were isolated and used in vitro expriments. The effects of NE on pVICs inflammation, apoptosis and calcification were detected by TUNEL assay, MTT assay, reverse transcription polymerase chain reaction (RT-PCR) and western blot. The effects of NE knockdown and NE activity inhibitor Alvelestat on pVICs inflammation, apoptosis and calcification under osteogenic medium induction were also detected by RT-PCR, western blot, alkaline phosphatase staining and alizarin red staining. Changes of Intracellular signaling pathways after NE treatment were measured by western blot. Apolipoprotein E⁻/⁻ (APOE⁻/⁻) mice were employed in this study to establish the important role of Alvelestat in valve calcification. HE was used to detected the thickness of valve. IHC was used to detected the NE and α-SMA expression in APOE⁻/⁻ mice. Echocardiography was employed to assess the heat function of APOE⁻/⁻ mice.

Results

The level and activity of NE were evaluated in patients with CAVD and calcified valve tissues. NE promoted inflammation, apoptosis and phenotype transition in pVICs in the presence or absence of osteogenic medium. Under osteogenic medium induction, NE silencing or NE inhibitor Alvelestat both suppressed the osteogenic differentiation of pVICs. Mechanically, NE played its role in promoting osteogenic differentiation of pVICs by activating the NF-κB and AKT signaling pathway. Alvelestat alleviated valve thickening and decreased the expression of NE and α-SMA in western diet-induced APOE⁻/⁻ mice. Alvelestat also reduced NE activity and partially improved the heart function of APOE⁻/⁻mice.

Conclusions

Collectively, NE is highly involved in the pathogenesis of valve calcification. Targeting NE such as Alvelestat may be a potential treatment for CAVD.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12967-022-03363-1.

Lipoprotein(a), a Lethal Player in Calcific Aortic Valve Disease

Calcified aortic valve disease (CAVD) is the most common valvular cardiovascular disease with increasing incidence and mortality. The primary treatment for CAVD is surgical or transcatheter aortic valve replacement and there remains a lack of effective drug treatment. Recently, lipoprotein (a) (Lp(a)) has been considered to play a crucial role in CAVD pathophysiology. Multiple studies have shown that Lp(a) represents an independent risk factor for CAVD. Moreover, Lp(a) mediates the occurrence and development of CAVD by affecting aortic valve endothelial dysfunction, indirectly promoting foam cell formation through oxidized phospholipids (OxPL), inflammation, oxidative stress, and directly promotes valve calcification. However, there is a lack of clinical trials with Lp(a) reduction as a primary endpoint. This review aims to explore the relationship and mechanism between Lp(a) and CAVD, and focuses on the current drugs that can be used as potential therapeutic targets for CAVD.

Aortic Stenosis: New Insights in Diagnosis, Treatment, and Prevention

There has been an explosion of diagnostic, prognostic, and treatment data in aortic stenosis (AS). Severity of AS should be based not only on valve hemodynamics, but underlying LV dysfunction and comorbidities. Indications for aortic valve replacement continue to evolve, extending to patients with less than severe AS. There are several trials to find a medical therapy to reduce the progression of AS. An application of artificial intelligence and clinical trial results will have a major impact in identifying asymptomatic patients and optimal treatment to the right patient at the right time.

Aortic stenosis (AS) is one of the most common valvular heart diseases and the number of patients with AS is expected to increase globally as the older population is growing fast. Since the majority of patients are elderly, AS is no longer a simple valvular heart disease of left ventricular outflow obstruction but is accompanied by other cardiac and comorbid conditions. Because of the significant variations of the disease, identifying patients at high risk and even earlier detection of patients with AS before developing symptomatic severe AS is becoming increasingly important. With the proven of efficacy and safety of transcatheter aortic valve replacement (TAVR) in the severe AS population, there is a growing interest in applying TAVR in those with less than severe AS. A medical therapy to reduce or prevent the progression in AS is actively investigated by several randomized control trials. In this review, we will summarize the most recent findings in AS and discuss potential future management strategies of patients with AS.

Calcific Aortic Stenosis-A Review on Acquired Mechanisms of the Disease and Treatments

Calcific aortic stenosis is a progressive disease that has become more prevalent in recent decades. Despite advances in research to uncover underlying biomechanisms, and development of new generations of prosthetic valves and replacement techniques, management of calcific aortic stenosis still comes with unresolved complications. In this review, we highlight underlying molecular mechanisms of acquired aortic stenosis calcification in relation to hemodynamics, complications related to the disease, diagnostic methods, and evolving treatment practices for calcific aortic stenosis.

Unplanned Percutaneous Coronary Revascularization After TAVR: A Multicenter International Registry

OBJECTIVES

This study sought to evaluate the incidence and causes of percutaneous coronary intervention (PCI) at different time periods following transcatheter aortic valve replacement (TAVR).

BACKGROUND

Coronary artery disease (CAD) and aortic stenosis frequently coexist, but the optimal management of CAD following TAVR remains incompletely elucidated.

METHODS

Patients undergoing unplanned PCI after TAVR were retrospectively included in an international multicenter registry.

RESULTS

Between July 2008 and March 2019, a total of 133 patients (0.9%; from a total cohort of 15,325) underwent unplanned PCI after TAVR (36.1% after balloon-expandable bioprosthesis, 63.9% after self-expandable bioprosthesis). The median time to PCI was 191 days (interquartile range: 59 to 480 days). The daily incidence of PCI was highest during the first week after TAVR and then declined over time. Overall, the majority of patients underwent PCI due to an acute coronary syndrome, and specifically 32.3% had non-ST-segment elevation myocardial infarction, 15.4% had unstable angina, 9.8% had ST-segment elevation myocardial infarction, and 2.2% had cardiac arrest. However, chronic coronary syndromes are the main indication beyond 2 years. PCI success was reported in almost all cases (96.6%), with no significant differences between patients treated with balloon-expandable and self-expandable bioprostheses (100% vs. 94.9%; p = 0.150).

CONCLUSIONS

Unplanned PCI after TAVR is rare, with an incidence declining over time after TAVR. The main indication to PCI is acute coronary syndrome in the first 2 years after TAVR, and thereafter chronic coronary syndromes become prevalent. Unplanned PCIs are frequently successfully performed after TAVR, with no apparent differences between balloon-expandable and self-expandable bioprostheses. (Revascularization After Transcatheter Aortic Valve Implantation [REVIVAL]; NCT03283501).

Percutaneous coronary intervention of complex calcific coronary lesions utilizing orbital atherectomy prior to transcatheter aortic valve replacement

BACKGROUND

Coronary artery disease (CAD), often with severe calcification, is present in up to 75% of patients with severe aortic stenosis (AS) referred for transcatheter aortic valve replacement (TAVR). Management of CAD in such patients is challenging. Orbital atherectomy (OA) is an effective treatment of severely calcified coronary lesions prior to stent implantation. However, there is limited data on the use of OA for percutaneous coronary intervention (PCI) to treat calcific CAD patients prior to TAVR (OA PCI + TAVR).

METHODS

Retrospective analysis of patients with moderate/severe calcific CAD and moderate/severe AS who underwent staged OA PCI + TAVR at one high-volume institution. Data were analyzed to assess the 1-year major adverse cardiac events after index OA PCI [MACE: death, target lesion revascularization (TLR), and myocardial infarction (MI)].

RESULTS

There were 18 patients (mean age of 82) treated with staged OA PCI + TAVR, and of those, 10 (56%) were male, 7 (39%) Caucasian, and 11 (61%) Hispanic/Latino. The average left ventricular ejection fraction was 49% and congestive heart failure was present in 12 patients (67%). There were no angiographic complications (0%), stent thrombosis (0%), or stroke events (0%). The 30-day and 1-year MACE rates were 5.6% (0% death, 0% TLR, 5.6% MI) and 17% (0% death, 11% TLR, and 17% MI [all non-Q-wave MI]), respectively.

CONCLUSIONS

In this single-center observational cohort series, patients with heavily calcified coronary lesions treated with OA prior to TAVR had low rates of MACE at 30 days and 1 year. The results demonstrate the feasibility and safety of OA for the treatment of complex calcific coronary lesions prior to TAVR. An up-to-date literature review of atherectomy before, during, or after TAVR in patients with concomitant severe AS and calcific CAD is also provided.

TABLE OF CONTENTS SUMMARY

There is limited data on the use of orbital atherectomy (OA) for percutaneous coronary intervention (PCI) to treat calcific coronary artery disease (CAD) patients prior to transcatheter aortic valve replacement (TAVR). Our primary aim was to evaluate the feasibility, safety, and 1-year outcome of OA PCI pre-TAVR in patients with complex CAD and severe aortic stenosis (AS). We also aimed to provide a brief up-to-date literature review of atherectomy before, during, or after TAVR in patients with concomitant severe AS and calcific CAD. This retrospective cohort study found that OA is feasible and safe for the treatment of severely calcified coronary lesions before TAVR, resulting in acceptable 30-day and 1-year outcomes.

Comparison of long-term mortality in patients who underwent transcatheter aortic valve replacement with or without anti-atherosclerotic therapy

Atherosclerosis is a risk factor for both aortic stenosis (AS) and coronary artery disease. This study aimed to investigate whether anti-atherosclerotic therapy (AT), defined as the simultaneous use of antiplatelet agents, statins, and renin aldosterone system inhibitors, had long-term clinical benefits for patients who underwent transcatheter aortic valve replacement (TAVR). Between October 2013 and May 2017, 2518 patients (31% men; median age, 85 years) who underwent TAVR in 14 Japanese centers were divided into two groups: patients who were prescribed anti-atherosclerotic therapy (AT, n = 567) and patients who were not (no AT, n = 1951). The median follow-up period for this cohort was 693 days (interquartile range, 389-870 days). Compared to no AT group, AT group was associated with significantly lower 2-year all-cause mortality (11.7% vs. 16.5%; log-rank p = 0.002) and 2-year cardiovascular mortality rates (3.5% vs. 6.0%; log-rank p = 0.017). In a propensity-matched cohort (n = 495 each; median follow-up, 710 days [IQR, 394 - 896 days]), patients in AT group had a lower prevalence of 2-year cardiovascular mortality (3.8% vs. 6.2%, log-rank p = 0.024) than that in the no AT group. In the multivariate stepwise regression analysis, AT was a significant predictor of cardiovascular mortality (hazard ratio 0.45; 95% confidence interval 0.25-0.80; p = 0.007). AT may improve survival in post-TAVR patients. Future studies are necessary to identify an optimal treatment regimen to improve long-term outcomes after TAVR.

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.

Dihydrotanshinone I inhibits aortic valve interstitial cell calcification via the SMAD1/5/8/NF-κB/ERK pathway

OBJECTIVES

In calcific aortic valve disease (CAVD), the valve interstitial cells (VIC) osteogenic phenotype changes can lead to thickening and calcification of the valve leaflets，eventually lead to restricted valve movement and life-threatening. This study aims to investigate the effect and mechanism of dihydrotanshinone I (DHI) on osteogenic medium (OM) induced osteogenic phenotypic transition of porcine valve interstitial cells (PVICs), which can provide theoretical and scientific basis for clinical intervention in CAVD.

METHODS AND RESULTS

Immunohistochemical methods were used to detect the expression of osteogenic indicators Runx2, OPN and inflammation indicators IL-1β and p-NF-κB in valve specimens of CAVD patients(N = 3) and normal controls(N = 1). PVICs stimulated by osteoblastic medium (OM) were treated with or without DHI. CCK8, ALP and Alizarin Red S staining were used to detect cell growth and calcification, respectively. The results showed that under the treated with DHI, compared with OM, the formation of calcium nodules was reduced, and the expression of calcification-related markers Runx2 and OPN were down-regulated, which quantified by qRT-PCR and western blot. In addition, on the basis of OM induction, DHI also inhibited the phosphorylation of the NF-κB/ERK1/2 and SMAD1/5/8 signaling pathway.

CONCLUSION

DHI (10 μM) treatment can reverse the osteogenic phenotypic transition of PVICs induced by osteogenic medium, and the mechanism may be related to NF-κB、ERK 1/2 and Smad1/5/8 pathways.

Collagen networks within 3D PEG hydrogels support valvular interstitial cell matrix mineralization

Enzymatically degradable hydrogels were designed for the 3D culture of valvular interstitial cells (VICs), and through the incorporation of various functionalities, we aimed to investigate the role of the tissue microenvironment in promoting the osteogenic properties of VICs and matrix mineralization. Specifically, porcine VICs were encapsulated in a poly(ethylene glycol) hydrogel crosslinked with a matrix metalloproteinase (MMP)-degradable crosslinker (KCGPQG↓IWGQCK) and formed via a thiol-ene photoclick reaction in the presence or absence of collagen type I to promote matrix mineralization. VIC-laden hydrogels were treated with osteogenic medium for up to 15 days, and the osteogenic response was characterized by the expression of RUNX2 as an early marker of an osteoblast-like phenotype, osteocalcin (OCN) as a marker of a mature osteoblast-like phenotype, and vimentin (VIM) as a marker of the fibroblast phenotype. In addition, matrix mineralization was characterized histologically with Von Kossa stain for calcium phosphate. Osteogenic response was further characterized biochemically with calcium assays, and physically via optical density measurements. When the osteogenic medium was supplemented with calcium chloride, OCN expression was upregulated and mineralization was discernable at 12 days of culture. Finally, this platform was used to screen various drug therapeutics that were assessed for their efficacy in preventing mineralization using optical density as a higher throughput readout. Collectively, these results suggest that matrix composition has a key role in supporting mineralization deposition within diseased valve tissue.

Thymoquinone Protects against Hyperlipidemia-Induced Cardiac Damage in Low-Density Lipoprotein Receptor-Deficient (LDL-R-/-) Mice via Its Anti-inflammatory and Antipyroptotic Effects

Hyperlipidemia is a risk factor for cardiac damage and cardiovascular disease. Increasing evidence has shown that dyslipidemia-related cardiac damage is associated with lipid accumulation, oxidative stress, and inflammation. Thymoquinone (TQ) is the major constituent of Nigella sativa, commonly known as black seed or black cumin, and is globally used in folk (herbal) medicine for treating and preventing a number of diseases and conditions. Several studies have shown that TQ can protect against cardiac damage. This study is aimed at investigating the possible protective effects of TQ on hyperlipidemia-induced cardiac damage in low-density lipoprotein receptor-deficient (LDL-R^−/−) mice. Eight-week-old male LDL-R^−/− mice were randomly divided into normal diet (ND), high-fat diet (HFD), and HFD and TQ (HFD+TQ) groups and were fed the different diets for eight weeks. Blood samples were obtained from the inferior vena cava in serum tubes and stored at -80°C until use. Some cardiac tissues were fixed in 10% formalin and then embedded in paraffin for histological evaluation. The remainder of the cardiac tissues was snap-frozen in liquid nitrogen for mRNA preparation or immunoblotting. The levels of metabolism-related factors, such as total cholesterol (TC), low-density lipoprotein-cholesterol (LDL-c), and high-sensitivity C-reactive protein (hs-CRP), were decreased in the HFD+TQ group compared with those in the HFD group. Periodic acid-Schiff staining demonstrated that lipid deposition was lower in the HFD+TQ group than in the HFD group. The expression of pyroptosis indicators (NOD-like receptor 3 (NLRP3), interleukin- (IL-) 1β, IL-18, and caspase-1), proinflammatory factors (IL-6 and tumor necrosis factor alpha (TNF-α)), and macrophage markers (cluster of differentiation (CD) 68) was significantly downregulated in the HFD+TQ group compared with that in the HFD group. Our results indicate that TQ may serve as a potential therapeutic agent for hyperlipidemia-induced cardiac damage.

Lipoprotein-associated phospholipase A2 activity, genetics and calcific aortic valve stenosis in humans

BACKGROUND

Lipoprotein-associated phospholipase A2 (Lp-PLA2) activity has been shown to predict calcific aortic valve stenosis (CAVS) outcomes. Our objective was to test the association between plasma Lp-PLA2 activity and genetically elevated Lp-PLA2 mass/activity with CAVS in humans.

METHODS AND RESULTS

Lp-PLA2 activity was measured in 890 patients undergoing cardiac surgery, including 476 patients undergoing aortic valve replacement for CAVS and 414 control patients undergoing coronary artery bypass grafting. After multivariable adjustment, Lp-PLA2 activity was positively associated with the presence of CAVS (OR=1.21 (95% CI 1.04 to 1.41) per SD increment). We selected four single nucleotide polymorphisms (SNPs) at the PLA2G7 locus associated with either Lp-PLA2 mass or activity (rs7756935, rs1421368, rs1805017 and rs4498351). Genetic association studies were performed in eight cohorts: Quebec-CAVS (1009 cases/1017 controls), UK Biobank (1350 cases/349 043 controls), European Prospective Investigation into Cancer and Nutrition-Norfolk (504 cases/20 307 controls), Genetic Epidemiology Research on Aging (3469 cases/51 723 controls), Malmö Diet and Cancer Study (682 cases/5963 controls) and three French cohorts (3123 cases/6532 controls), totalling 10 137 CAVS cases and 434 585 controls. A fixed-effect meta-analysis using the inverse-variance weighted method revealed that none of the four SNPs was associated with CAVS (OR=0.99 (95% CI 0.96 to 1.02, p=0.55) for rs7756935, 0.97 (95% CI 0.93 to 1.01, p=0.11) for rs1421368, 1.00 (95% CI 1.00 to 1.01, p=0.29) for rs1805017, and 1.00 (95% CI 0.97 to 1.04, p=0.87) for rs4498351).

CONCLUSIONS

Higher Lp-PLA2 activity is significantly associated with the presence of CAVS and might represent a biomarker of CAVS in patients with heart disease. Results of our genetic association study suggest that Lp-PLA2 is however unlikely to represent a causal risk factor or therapeutic target for CAVS.

Genetic and In Vitro Inhibition of PCSK9 and Calcific Aortic Valve Stenosis

The authors investigated whether PCSK9 inhibition could represent a therapeutic strategy in calcific aortic valve stenosis (CAVS). A meta-analysis of 10 studies was performed to determine the impact of the PCSK9 R46L variant on CAVS, and the authors found that CAVS was less prevalent in carriers of this variant (odds ratio: 0.80 [95% confidence interval: 0.70 to 0.91]; p = 0.0011) compared with noncarriers. PCSK9 expression was higher in the aortic valves of patients CAVS compared with control patients. In human valve interstitials cells submitted to a pro-osteogenic medium, PCSK9 levels increased and a PCSK9 neutralizing antibody significantly reduced calcium accumulation.

Aortic valve calcification in the era of non-coding RNAs: The revolution to come in aortic stenosis management?

Aortic valve stenosis remains the most frequent structural heart disease, especially in the elderly. During the last decade, we noticed an important consideration and a huge number of publications related to the medical and surgical treatment of this disease. However, the molecular aspect of this degenerative issue has also been more widely studied recently. As evidenced in oncologic but also cardiac research fields, the emergence of microRNAs in the molecular screening and follow-up makes them potential biomarkers in the future, for the diagnosis, follow-up and treatment of aortic stenosis. Herein, we present a review on the implication of microRNAs in the aortic valve disease management. After listing and describing the main miRNAs of interest in the field, we provide an outline to develop miRNAs as innovative biomarkers and innovative therapeutic strategies, and describe a groundbreaking pre-clinical study using inhibitors of miR-34a in a pre-clinical model of aortic valve stenosis.

NFκB (Nuclear Factor κ-Light-Chain Enhancer of Activated B Cells) Activity Regulates Cell-Type-Specific and Context-Specific Susceptibility to Calcification in the Aortic Valve

OBJECTIVE

Although often studied independently, little is known about how aortic valve endothelial cells and valve interstitial cells interact collaborate to maintain tissue homeostasis or drive valve calcific pathogenesis. Inflammatory signaling is a recognized initiator of valve calcification, but the cell-type-specific downstream mechanisms have not been elucidated. In this study, we test how inflammatory signaling via NFκB (nuclear factor κ-light-chain enhancer of activated B cells) activity coordinates unique and shared mechanisms of valve endothelial cells and valve interstitial cells differentiation during calcific progression. Approach and Results: Activated NFκB was present throughout the calcific aortic valve disease (CAVD) process in both endothelial and interstitial cell populations in an established mouse model of hypercholesterolemia-induced CAVD and in human CAVD. NFκB activity induces endothelial to mesenchymal transformation in 3-dimensional cultured aortic valve endothelial cells and subsequent osteogenic calcification of transformed cells. Similarly, 3-dimensional cultured valve interstitial cells calcified via NFκB-mediated osteogenic differentiation. NFκB-mediated endothelial to mesenchymal transformation was directly demonstrated in vivo during CAVD via genetic lineage tracking. Genetic deletion of NFκB in either whole valves or valve endothelium only was sufficient to prevent valve-specific molecular and cellular mechanisms of CAVD in vivo despite the persistence of a CAVD inducing environment.

CONCLUSIONS

Our results identify NFκB signaling as an essential molecular regulator for both valve endothelial and interstitial participation in CAVD pathogenesis. Direct demonstration of valve endothelial cell endothelial to mesenchymal transformation transmigration in vivo during CAVD highlights a new cellular population for further investigation in CAVD morbidity. The efficacy of valve-specific NFκB modulation in inhibiting hypercholesterolemic CAVD suggests potential benefits of multicell type integrated investigation for biological therapeutic development and evaluation for CAVD.

Identification of key genes and pathways in calcific aortic valve disease by bioinformatics analysis

Background

Calcific aortic valve disease (CAVD) is the most common type of valvular heart disease in the elderly. This study is aimed to explore molecular mechanism of CAVD via bioinformatics analysis.

Methods

The gene expression profiles of GSE51472 (including 5 normal aortic valve and 5 calcified aortic valve) and GSE83453 (including 8 normal aortic valve and 19 calcified aortic valve) were downloaded from the Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs) were screened using the MetaDE package in R software. Functional and pathway enrichment analysis were performed based on Gene ontology (GO) and KEGG pathway database. Then, STRING database, Cytoscape and MCODE were applied to construct the protein-protein interaction (PPI) network and screen hub genes. Pathway enrichment analysis was further performed for hub genes and gene clusters identified via module analysis.

Results

A total of 107 DEGs were identified in CAVD (53 up-regulated genes, and 54 down-regulated genes), and they were mainly enriched in the terms of immune response, extracellular matrix organization, leukocyte transendothelial migration, cell adhesion molecules (CAMs), and fatty acid metabolism. Five hub genes including VCAM1, MMP9, ITGB2, RAC2, and vWF were identified via PPI network, which were mainly enriched in terms of leukocyte transendothelial migration and cell adhesion. An independently down-regulated protein cluster containing ALDH2, HIBCH, ACADVL, ECHDC2, VAT1L, and MAOA was also identified via PPI network.

Conclusions

The present study identified VCAM1, MMP9, ITGB2, RAC2, vWF and ALDH2 as key genes in the progression of CAVD. Immune cells infiltration might play a key role in the progression of CAVD, while ALDH2-mediated detoxification effect might play a protective role in CAVD. Further studies are needed to elucidate the pathogenesis of CAVD.

Genetic Variation in LPA, Calcific Aortic Valve Stenosis in Patients Undergoing Cardiac Surgery, and Familial Risk of Aortic Valve Microcalcification

Importance

Genetic variants at the LPA locus are associated with both calcific aortic valve stenosis (CAVS) and coronary artery disease (CAD). Whether these variants are associated with CAVS in patients with CAD vs those without CAD is unknown.

Objective

To study the associations of LPA variants with CAVS in a cohort of patients undergoing heart surgery and LPA with CAVS in patients with CAD vs those without CAD and to determine whether first-degree relatives of patients with CAVS and high lipoprotein(a) (Lp[a]) levels showed evidence of aortic valve microcalcification.

Design, Setting, and Participants

This genetic association study included patients undergoing cardiac surgery from the Genome-Wide Association Study on Calcific Aortic Valve Stenosis in Quebec (QUEBEC-CAVS) study and patients with CAD, patients without CAD, and control participants from 6 genetic association studies: the UK Biobank, the European Prospective Investigation of Cancer (EPIC)-Norfolk, and Genetic Epidemiology Research on Aging (GERA) studies and 3 French cohorts. In addition, a family study included first-degree relatives of patients with CAVS. Data were collected from January 1993 to September 2018, and analysis was completed from September 2017 to September 2018.

Exposures

Case-control studies.

Main Outcomes and Measures

Presence of CAVS according to a weighted genetic risk score based on 3 common Lp(a)-raising variants and aortic valve microcalcification, defined as the mean tissue to background ratio of 1.25 or more, measured by fluorine 18-labeled sodium fluoride positron emission tomography/computed tomography.

Results

This study included 1009 individuals undergoing cardiac surgery and 1017 control participants in the QUEBEC-CAVS cohort; 3258 individuals with CAVS and CAD, 41 100 controls with CAD, 2069 individuals with CAVS without CAD, and 380 075 control participants without CAD in the UK Biobank, EPIC-Norfolk, and GERA studies and 3 French cohorts combined; and 33 first-degree relatives of 17 patients with CAVS and high Lp(a) levels (≥60 mg/dL) and 23 control participants with normal Lp(a) levels (<60 mg/dL). In the QUEBEC-CAVS study, each SD increase of the genetic risk score was associated with a higher risk of CAVS (odds ratio [OR], 1.35 [95% CI, 1.10-1.66]; P = .003). Each SD increase of the genetic risk score was associated with a higher risk of CAVS in patients with CAD (OR, 1.30 [95% CI, 1.20-1.42]; P < .001) and without CAD (OR, 1.33 [95% CI, 1.14-1.55]; P < .001). The percentage of individuals with a tissue to background ratio of 1.25 or more or CAVS was higher in first-degree relatives of patients with CAVS and high Lp(a) (16 of 33 [49%]) than control participants (3 of 23 [13%]; P = .006).

Conclusions and Relevance

In this study, a genetically elevated Lp(a) level was associated with CAVS independently of the presence of CAD. These findings support further research on the potential usefulness of Lp(a) cascade screening in CAVS.

Incidental Findings Diagnosed during Preprocedural Evaluation of TAVR

Introduction

Transcatheter aortic valve replacement is an important therapeutic option for aortic stenosis (AS) patients who have high surgical risk. TAVR is a complex procedure. Proper preparation of the patient is of significant importance for the final success and affects the morbidity and mortality of the TAVR directly. Pre-TAVR computed tomography is one of the corner stones of these preparation steps, and many patients get some incidental diagnoses.

Materials and Methods

In this trial, we have investigated 155 patients who had underwent TAVR between February 2013 and March 2017 at Hacettepe University Adult Hospital Cardiology Clinic.

Results

Total number of incidental diagnoses was 541, and 451 of them were the first diagnoses. Total number of cardiovascular findings and noncardiovascular findings was 369 and 172, respectively. The most common cardiovascular finding is atherosclerotic heart disease (139, 89.6%). The most common noncardiovascular finding is pulmonary nodule (41, 26.4%). 143 of 155 patients had at least one incidental diagnosis after the reassessment, and 33 different diagnoses were identified with computed tomography. The mean STS-PROM was 8.38% (range 2.8% to 23%), and the mean STS-PROM was calculated 9.4% (range 3.6% to 23%) after the reassessment of computed tomography.

Conclusion

Preprocedural evaluation is one of the most important steps in TAVR. Computed tomography imaging provides extensive information, not only for procedure planning. Our findings emphasize that computed tomography has a crucial role for the preprocedural evaluation of TAVR candidates.

Coenzyme Q10 protects against hyperlipidemia-induced cardiac damage in apolipoprotein E-deficient mice

BACKGROUND

Hyperlipidemia is a well-established risk factor for cardiac damage, which can lead to cardiovascular diseases. Many studies have shown that Coenzyme Q10(CoQ10) protects against cardiac damage in vivo. The aim of this study was to investigate the possible protective effects of CoQ10 against cardiac damage in apolipoprotein E-deficient (ApoE^-/-) mice.

METHODS

Eight-week-old male C57BL/6 and ApoE^-/- mice were randomly divided into four groups: C57BL/6 mice fed a normal diet (C57BL/6 group); C57BL/6 mice fed a normal diet + CoQ10 (C57BL/6 + CoQ10 group); ApoE^-/- mice fed a high-fat diet (ApoE^-/- HD group), and ApoE^-/- mice fed a high-fat diet + CoQ10 (ApoE^-/- HD + CoQ10 group). All groups were fed the different diets for 16 weeks. Blood samples were obtained from the inferior vena cava and collected in serum tubes. The samples were then stored at - 80 °C until used. Coronal sections of heart tissues were fixed in 10% formalin and then embedded in paraffin for histological evaluation. The remainder of the heart tissues was snap-frozen in liquid nitrogen for mRNA or immunohistochemical analysis.

RESULTS

The metabolic parameters such as total cholesterol (TC), low-density lipoprotein-cholesterol (LDL-c), and triglycerides (TG) levels were lower in ApoE^-/-HD + CoQ10 mice than in ApoE^-/- HD mice. There were significant pathophysiological changes (H&E, PAS, Masson and CD68 staining) in ApoE^-/- mice in the HD group compared with those in the HD + CoQ10 group. CoQ10 reduced HD-induced cardiac tissue damage via autophagy (p62 and LC3), as evidenced by immunoblotting, immunohistochemistry, and RT-qPCR. CoQ10 also inhibited inflammation (IL-6 and TNF-α) gene expression in ApoE^-/- mice.

CONCLUSIONS

These results indicate that CoQ10 is a potential therapeutic target for cardiac damage caused by hyperlipidemia.

MicroRNA-138 Suppresses Osteoblastic Differentiation of Valvular Interstitial Cells in Degenerative Calcific Aortic Valve Disease

The aim of this study was to explore the function of miR-138 in the pathogenesis of degenerative calcific aortic valve disease (DCAVD).Aortic valve calcification tissue and normal tissue from DCAVD patients were collected to detect the expression of miR-138 by qRT-PCR, and immunohistochemical staining was performed to identify the phenotype of valve interstitial cells. QRT-PCR was performed to analyze the expression of miR-138, Runx2, MSX2, and ALP at day 7 after osteogenic differentiation. Alkaline phosphatase activity assay was performed at day 14 after osteogenic differentiation. Alizarin red staining was used to analyze the calcium nodule formation. TargetScan was used to predict potential targets of miR-138. QRT-PCR and Western blotting were performed to analyze the expression of FOXC1 in valve interstitial cells (VICs). The aortic valve calcification was evaluated by quantitative analysis of the velocity in the aortic annulus and transvalvular pressure gradients.In this study, we demonstrated the role of miR-138 in VIC osteogenesis. QRT-PCR results revealed miR-138 was significantly down-regulated in calcified aortic valves compared with non-calcified valves. MiR-138 overexpression inhibited VIC osteogenic differentiation in vitro, while down-regulation of miR-138 enhanced the process. Target prediction analysis and dual-luciferase reporter assay confirmed FOXC1 was a direct target of miR-138. Further research found FOXC1 overexpression promoted VIC osteogenic differentiation. In addition, animal experiments validated indirectly miR-138 could suppress aortic valve calcification.Our findings suggest miR-138 could function as a new inhibitor of VIC osteogenic differentiation, which may act by targeting FOXC1.

Cell Sources for Tissue Engineering Strategies to Treat Calcific Valve Disease

Cardiovascular calcification is an independent risk factor and an established predictor of adverse cardiovascular events. Despite concomitant factors leading to atherosclerosis and heart valve disease (VHD), the latter has been identified as an independent pathological entity. Calcific aortic valve stenosis is the most common form of VDH resulting of either congenital malformations or senile “degeneration.” About 2% of the population over 65 years is affected by aortic valve stenosis which represents a major cause of morbidity and mortality in the elderly. A multifactorial, complex and active heterotopic bone-like formation process, including extracellular matrix remodeling, osteogenesis and angiogenesis, drives heart valve “degeneration” and calcification, finally causing left ventricle outflow obstruction. Surgical heart valve replacement is the current therapeutic option for those patients diagnosed with severe VHD representing more than 20% of all cardiac surgeries nowadays. Tissue Engineering of Heart Valves (TEHV) is emerging as a valuable alternative for definitive treatment of VHD and promises to overcome either the chronic oral anticoagulation or the time-dependent deterioration and reintervention of current mechanical or biological prosthesis, respectively. Among the plethora of approaches and stablished techniques for TEHV, utilization of different cell sources may confer of additional properties, desirable and not, which need to be considered before moving from the bench to the bedside. This review aims to provide a critical appraisal of current knowledge about calcific VHD and to discuss the pros and cons of the main cell sources tested in studies addressing in vitro TEHV.

Association of matrix metalloproteinase 3 and endogenous inhibitors with inflammatory markers in mitral valve disease and calcification

Calcific mitral valve stenosis (MVS) is a common disease characterized by extensive remodeling of the extracellular matrix via matrix metalloproteinases (MMPs). The mechanism of calcification due to extensive matrix remodeling remains unclear. In this study, we investigated the relationship between MMP-3, tissue inhibitors of metalloproteinases (TIMPs) as well as pro-inflammatory cytokines and the phenomenon of calcification in MVS. 212 patients having rheumatic mitral stenosis (RMS) and 155 healthy control subjects were recruited in the Cardiology Department of La Rabta Hospital University. Levels of MMP-3, TIMPs, IL-6 and TNF-α were measured by ELISA sandwich assay, hs-CRP was measured by immunoturbidimetry. Plasma levels of MMP-3, TIMP-1 and MMP-3/TIMP-2 ratio were lower only in RMS women in comparison to the control group. Calcification degree correlated positively with MMP-3 in women and men. In addition, calcification was correlated positively with MMP-3/TIMPs ratio in women patients. The inflammatory parameters were positively associated with extracellular matrix turnover biomarkers in men patients. In patients, the level of MMP-3 was increased in men and women with a calcification score ≥ 5. In addition, MMP-3 level predicted the occurrence of calcification. At ROC curves analysis, the cut-off MMP-3 level was in women was 9.21 ng/ml (sensitivity 51.1%, specificity 89.3%) and in men was 12.84 ng/ml (sensitivity 78.6%, specificity 77.8%). The high levels of MMP-3 and the biomarkers of inflammation contribute to valvular remodeling and calcification of the mitral valve.

Deletion of calponin 2 attenuates the development of calcific aortic valve disease in ApoE-/- mice

Calcific aortic valve disease (CAVD) is a leading cause of cardiovascular mortality and lacks non-surgical treatment. The pathogenesis of CAVD involves perturbation of valvular cells by mechanical stimuli, including shear stress, pressure load and leaflet stretch, of which the molecular mechanism requires further elucidation. We recently demonstrated that knockout (KO) of Cnn2 gene that encodes calponin isoform 2, a mechanoregulated cytoskeleton protein, attenuates atherosclerosis in ApoE KO mice. Here we report that Cnn2 KO also decreased calcification of the aortic valve in ApoE KO mice, an established model of CAVD. Although myeloid cell-specific Cnn2 KO highly effectively attenuated vascular atherosclerosis that shares many pathogenic processes with CAVD, it did not reduce aortic valve calcification in ApoE KO mice. Indicating a function in the pathogenesis of CAVD, calponin 2 participates in myofibroblast differentiation that is a leading step in the development of CAVD. The aortic valves of ApoE KO mice exhibited increased expression of calponin 2 and smooth muscle actin (SMA), a hallmark of myofibroblasts. The expression of calponin 2 increased during myofibroblast-like differentiation of primary sheep aortic valve interstitial cells and during the osteogenic differentiation of mouse myofibroblasts. Cnn2 KO attenuated TGFβ1-induced differentiation of myofibroblasts in culture as shown by the lower expression of SMA and less calcification than that of wild type (WT) cells. These findings present calponin 2 as a novel molecular target for the treatment and prevention of CAVD.

A New Growth Model for Aortic Valve Calcification

Calcific aortic valve disease (CAVD) is a progressive disease in which minerals accumulate in the tissue of the aortic valve cusps, stiffening them and preventing valve opening and closing. The process of valve calcification was found to be similar to that of bone formation including cell differentiation to osteoblast-like cells. Studies have shown the contribution of high strains to calcification initiation and growth process acceleration. In this paper, a new strain-based calcification growth model is proposed. The model aims to explain the unique shape of the calcification and other disease characteristics. The calcification process was divided into two stages: Calcification initiation and calcification growth. The initiation locations were based on previously published findings and a reverse calcification technique (RCT), which uses computed tomography (CT) scans of patients to reveal the calcification initiation point. The calcification growth process was simulated by a finite element model of one aortic valve cusp loaded with cyclic loading. Similar to Wolff's law, describing bone response to stress, our model uses strains to drive calcification formation. The simulation grows calcification from its initiation point to its full typical stenotic shape. Study results showed that the model was able to reproduce the typical calcification growth pattern and shape, suggesting that strain is the main driving force behind calcification progression. The simulation also sheds light on other disease characteristics, such as calcification growth acceleration as the disease progresses, as well as sensitivity to hypertension.

Realistic Vascular Replicator for TAVR Procedures

Transcatheter aortic valve replacement (TAVR) is an over-the-wire procedure for treatment of severe aortic stenosis (AS). TAVR valves are conventionally tested using simplified left heart simulators (LHS). While those provide baseline performance reliably, their aortic root geometries are far from the anatomical in situ configuration, often overestimating the valves' performance. We report on a novel benchtop patient-specific arterial replicator designed for testing TAVR and training interventional cardiologists in the procedure. The Replicator is an accurate model of the human upper body vasculature for training physicians in percutaneous interventions. It comprises of fully-automated Windkessel mechanism to recreate physiological flow conditions. Calcified aortic valve models were fabricated and incorporated into the Replicator, then tested for performing TAVR procedure by an experienced cardiologist using the Inovare valve. EOA, pressures, and angiograms were monitored pre- and post-TAVR. A St. Jude mechanical valve was tested as a reference that is less affected by the AS anatomy. Results in the Replicator of both valves were compared to the performance in a commercial ISO-compliant LHS. The AS anatomy in the Replicator resulted in a significant decrease of the TAVR valve performance relative to the simplified LHS, with EOA and transvalvular pressures comparable to clinical data. Minor change was seen in the mechanical valve performance. The Replicator showed to be an effective platform for TAVR testing. Unlike a simplified geometric anatomy LHS, it conservatively provides clinically-relevant outcomes and complement it. The Replicator can be most valuable for testing new valves under challenging patient anatomies, physicians training, and procedural planning.

Toll-Like Receptors, Inflammation, and Calcific Aortic Valve Disease

Inflammation, the primary response of innate immunity, is essential to initiate the calcification process underlying calcific aortic valve disease (CAVD), the most prevalent valvulopathy in Western countries. The pathogenesis of CAVD is multifactorial and includes inflammation, hemodynamic factors, fibrosis, and active calcification. In the development of CAVD, both innate and adaptive immune responses are activated, and accumulating evidences show the central role of inflammation in the initiation and propagation phases of the disease, being the function of Toll-like receptors (TLR) particularly relevant. These receptors act as sentinels of the innate immune system by recognizing pattern molecules from both pathogens and host-derived molecules released after tissue damage. TLR mediate inflammation via NF-κB routes within and beyond the immune system, and play a crucial role in the control of infection and the maintenance of tissue homeostasis. This review outlines the current notions about the association between TLR signaling and the ensuing development of inflammation and fibrocalcific remodeling in the pathogenesis of CAVD. Recent data provide new insights into the inflammatory and osteogenic responses underlying the disease and further support the hypothesis that inflammation plays a mechanistic role in the initiation and progression of CAVD. These findings make TLR signaling a potential target for therapeutic intervention in CAVD.

Relation of an Echocardiographic-Based Cardiac Calcium Score to Mitral Stenosis Severity and Coronary Artery Disease in Patients with Severe Aortic Stenosis

Patients with calcific aortic stenosis (AS) often have diffuse cardiac calcification involving the mitral valve apparatus and coronary arteries. We examined the association between global cardiac calcification quantified by a previously validated echocardiographic calcium score (eCS) with the severity of mitral stenosis (MS) and coronary artery disease (CAD) in patients with a clinical diagnosis of severe calcific AS. In this sample of 147 patients (mean age 81 ± 9 years, 50% male), 81 patients (55%) were determined by echocardiography to have some degree of MS. Higher mean eCS was observed in patients with more severe MS (r = 0.54, p < 0.0001). Higher eCS was also inversely associated with mitral valve area (r = -0.31, p = 0.001) and positively associated with mitral valve mean pressure gradient (r = 0.46, p < 0.0001) and mitral valve peak flow velocity (r = 0.55, p < 0.0001). The area under the receiver operating characteristic curve for using eCS to predict the presence of MS was 0.76. An eCS ≥ 8 predicted MS with a sensitivity of 68%, specificity of 76%, positive predictive value of 77%, and negative predictive value of 66%. High eCS, relative to low eCS, was associated with 2.70 times the adjusted odds of CAD (odds ratio = 2.70, 95% confidence interval 1.02 to 7.17). In conclusion, global cardiac calcification is associated with MS and CAD in patients with severe calcific AS, and eCS shows ability to predict the presence of MS. This study suggests that a simple eCS may be used as part of a risk-stratification tool in patients with severe calcific aortic valve stenosis.