Valvular Calcification Research Articles

TRPM4: New actor in osteogenic differentiation of human valvular interstitial cells

Transient receptor potential melastatin 4 (TRPM4) protein, a non-selective cation channel activated by calcium, is involved in cardiac fibroblasts remodeling. Its expression was reported in human valvular interstitial cells (VIC) with similar properties than fibroblasts, and its protein expression is increased on calcified aortic valves from patients suffering of aortic stenosis. VIC osteogenic differentiation is a key element in valvular calcification, which is, at term, responsible of aortic stenosis. The purpose of this study is to evaluate the implication of TRPM4 in human VIC osteogenic differentiation. VIC are isolated by enzymatic digestion from human aortic valves obtained from patients undergoing surgical aortic valve replacement. They are maintained 14 days in procalcifying media (2.7 mM calcium/2.5 mM phosphate), with or without 9-phenanthrol, a pharmacological TRPM4 inhibitor. Channel expression and functionality were followed respectively by PCR, Western Blot and electrophysiological recordings in the inside-out configuration of the patch clamp technique. Osteogenic differentiation of VIC was evaluated by measuring hydroxyapatite crystals by Alizarin red staining and by monitoring the protein expression of the osteogenic markers, BMP2 and RUNX2. A typical TRPM4 current was detected on VIC: its current-voltage relationship was linear with a conductance of 20.3 pS; the channel exhibited similar permeability for Na+ and K+; it was more activated in positive voltages and with increasing concentrations of internal Ca2+; the current was dose-dependently inhibited by 9-phenanthrol. TRPM4 mRNA and protein expression on VIC was confirmed by PCR and Western Blot. When maintained in procalcifying media, VIC developed hydroxyapatite crystals. Application of 9-phenanthrol (3.10-6 M) reduced mineralization by 30% without affecting cell viability. Moreover, it significantly reduced BMP2 and RUNX2 expression. Thereby, TRPM4 participates in osteogenic differentiation of human VIC in culture. Next studies of our unit are to evaluate whether TRPM4 repression by shRNA confirms those results.

Abstract 340: γ-carboxylated Growth Arrest Specific Protein 6 Differentially Induces Calcification In Human Aortic Valves

Introduction: Growth arrest specific protein 6 (GAS6) is a secreted γ-carboxylated vitamin K-dependent protein with roles in cell proliferation and migration. The role of GAS6 and post-translational γ-carboxylation in calcific aortic valve disease (CAVD) has yet to be evaluated. Hypothesis: Using proteomics, we identified GAS6 as a novel protein abundant in valve tissue and valvular interstitial cells (VICs), and assessed the hypothesis that γ-carboxylated GAS6 has a mechanistic role in the development of CAVD. Methods: Whole aortic valve and tissue extracellular vesicle (EV) label-free proteomics, valve histopathology, and valvular interstitial cell isolation was performed on human specimens collected from surgical aortic valve replacements for aortic stenosis at Brigham and Women’s Hospital. EVs were isolated from whole valves using ultracentrifugation and Optiprep density gradients. Mass-spectrometry will confirm γ-carboxylation. Results: GAS6 abundance was elevated in valvular areas of calcification compared to non-diseased regions (log2 FC=5, q=4.2E-10), and were enriched in GO terms associated with exosome and vesicular transport (N=18). Due to the role of EVs in ectopic cardiovascular calcification, tissue EVs were isolated from calcified aortic valves (N=9), and proteomics identified GAS6 in the vesicle-enriched fractions. Immunohistopathology of GAS6 in CAVD specimens identified co-localization of GAS6 with inflammation and calcification. Protein expression of GAS6 from VICs was significantly increased by media supplemented with organic phosphate (β-glycerophosphate) (N=5-8, p<0.05), but markedly decreased by supplementation with inorganic phosphate (NaH 2 PO 4 ) (N=5-8, p<0.05), despite both conditions generating Alizarin red positive calcification. GAS6 knockdown prevented calcification only in the setting of organic phosphate stimulation. Conclusions: GAS6 is a novel protein of pathological significance in CAVD. EV enrichment of GAS6 and unappreciated differential mechanistic roles of phosphate sources impacts valvular calcification, potentially through γ-carboxylation regulation. GAS6 has an unrecognized role in CAVD, which may have important implications for future disease pharmacotherapy.

Capsaicin inhibits aortic valvular interstitial cell calcification via the redox-sensitive NFκB/AKT/ERK1/2 pathway

Calcific aortic valve stenosis (CAVS), the third most prevalent cardiovascular disorder is known to impose a huge social and economic burden on patients. However, no pharmacotherapy has yet been established. Aortic valve replacement is the only treatment option, although its lifelong efficacy is not guaranteed and involves inevitable complications. So, there is a crucial need to find novel pharmacological targets to delay or prevent CAVS progression. Capsaicin is well known for its anti-inflammatory and antioxidant properties and has recently been revealed to inhibit arterial calcification. We thus investigated the effect of capsaicin in attenuating aortic valve interstitial cells (VICs) calcification induced by pro-calcifying medium (PCM). Capsaicin reduced the level of calcium deposition in calcified VICs, along with reductions in gene and protein expression of the calcification markers Runx2, osteopontin, and BMP2. Based on Gene Ontology biological process and Kyoto Encyclopedia of Genes and Genomes pathway analysis oxidative stress, AKT and AGE–RAGE signaling pathways were selected. The AGE–RAGE signaling pathway activates oxidative stress and inflammation-mediated pathways including ERK and NFκB signaling pathways. Capsaicin successfully inhibited oxidative stress- and reactive oxygen species-related markers NOX2 and p22phox. The markers of the AKT, ERK1/2, and NFκB signaling pathways, namely, phosphorylated AKT, ERK1/2, NFκB, and IκBα were upregulated in calcified cells, while being significantly downregulated upon capsaicin treatment. Capsaicin attenuates VICs calcification in vitro by inhibition of redox-sensitive NFκB/AKT/ERK1/2 signaling pathway, indicating its potential as a candidate to alleviate CAVS.

Fluid-structure interaction analysis of transcatheter aortic valve implantation.

Transcatheter aortic valve implantation (TAVI) is a minimally invasive intervention for the treatment of severe aortic valve stenosis. The main cause of failure is the structural deterioration of the implanted prosthetic leaflets, possibly inducing a valvular re-stenosis 5-10 years after the implantation. Based solely on pre-implantation data, the aim of this work is to identify fluid-dynamics and structural indices that may predict the possible valvular deterioration, in order to assist the clinicians in the decision-making phase and in the intervention design. Patient-specific, pre-implantation geometries of the aortic root, the ascending aorta, and the native valvular calcifications were reconstructed from computed tomography images. The stent of the prosthesis was modeled as a hollow cylinder and virtually implanted in the reconstructed domain. The fluid-structure interaction between the blood flow, the stent, and the residual native tissue surrounding the prosthesis was simulated by a computational solver with suitable boundary conditions. Hemodynamical and structural indicators were analyzed for five different patients that underwent TAVI - three with prosthetic valve degeneration and two without degeneration - and the comparison of the results showed a correlation between the leaflets' structural degeneration and the wall shear stress distribution on the proximal aortic wall. This investigation represents a first step towards computational predictive analysis of TAVI degeneration, based on pre-implantation data and without requiring additional peri-operative or follow-up information. Indeed, being able to identify patients more likely to experience degeneration after TAVI may help to schedule a patient-specific timing of follow-up.

Relation between Sclerostin and Valvular Calcification in Hemodialysis Patients

Relation between Sclerostin and Valvular Calcification in Hemodialysis Patients

Aortic Valve Calcium Score in Patients Undergoing Aortic Valve Replacement Surgery

Introduction: The calcium score of the aortic valve is a simple and rapid method that allows to evaluate the degree of calcification emerging as a non-invasive technique in the preoperative period that allows to assess the severity of the aortic stenosis and the possible adverse events of the surgery. Methodology: A cross-sectional descriptive study was conducted in patients with aortic valve disease who underwent surgery at Provincial University Heart Center “Ernesto Guevara”, Villa Clara, from September 2019 to March 2021. Result: Patients aged 60 to 69 years (47.5%), male sex (85%), with hypertension (87.5%) and coffee consumption (77.5%) being the most frequent history and toxic habit. In (80%) of cases, the main diagnosis was aortic stenosis, and the most frequent electrocardiographic finding was sinus rhythm (97.5%). Echocardiographic variables, normal LVEF (75%). With predominance by the degree of stenosis according to the valvular area (85%), peak speed and peak gradient with (62.5%) respectively and medium gradient (65%). Conclusion: Stenosis with peak, medium and moderate peak velocity gradient presented the highest values of calcium score of the aortic valve. Most of the operated patients show moderate, severe calcium score, unrelated to the coronary calcium score. In the intraoperative variables, the very calcified aortic valve predominated, anoxic arrest and prolonged extracorporeal circulation, which were in the severe form of the valvular calcium score. The most frequent post-surgical complications are anemia, atrioventricular rhythm and conduction disorders, and pleural effusion.

Bone fragility, sarcopenia and cardiac calcifications in an elderly population: a preliminary study

Cardiovascular disease, osteoporosis and sarcopenia are very common age-related conditions. This study aimed at investigating the relationships of cardiac calcifications, as assessed by using GCCS with BMD, fragility fractures and sarcopenia in elderly subjects. In a cohort of 106 subjects (age 70.4 ± 5.8 yrs) we measured lumbar (BMD-LS), femoral BMD (femoral neck: BMD-FN, total femur: BMD-TH) and body composition (BMD-WB) with Dual-energy X-ray Absorptiometry (DXA) method. We also evaluated the presence of sarcopenia on the basis of the EWGSOP Consensus. All subjects, simultaneously, underwent to a transthoracic color doppler echocardiography exam to assess the presence of cardiac calcifications. The degree of non coronaric cardiac calcifications was evaluated using the Global Cardiac Calcium Score (GCCS). The degree of cardiac calcification assessed by GCCS was significantly higher in osteoporotic patients (p < 0.001). Furthermore, an inverse correlation emerged between BMD and GCCS, statistical significance was found at lumbar spine and femoral sub-regions in female population (p < 0.01). Moreover by dividing population according to the presence of fragility fractures, we observed that GCCS values were significantly higher in subjects with fractures in respect of non-fractured ones (p < 0.05). Multiple regression models showed that BMD-LS and BMD-FT were independently associated with cardiac calcification. GCCS values were significantly associated with BMI and ASMM in women (p < 0.01 and p < 0.05, respectively) and with handgrip strength in men (p < 0.05). Our data confirm the presence of a relationship between cardiac calcifications and decreased BMD values. It's also the first study that relates sarcopenia and valvular calcifications.

Redefying the therapeutic strategies against cardiorenal morbidity and mortality: Patient phenotypes.

Chronic kidney disease (CKD) patients face an unacceptably high morbidity and mortality, mainly from cardiovascular diseases. Diabetes mellitus, arterial hypertension and dyslipidemia are highly prevalent in CKD patients. Established therapeutic protocols for the treatment of diabetes mellitus, arterial hypertension, and dyslipidemia are not as effective in CKD patients as in the general population. The role of non-traditional risk factors (RF) has gained interest in the last decades. These entail the deranged clinical spectrum of secondary hyperparathyroidism involving vascular and valvular calcification, under the term "CKD-mineral and bone disorder" (CKD-MBD), uremia per se, inflammation and oxidative stress. Each one of these non-traditional RF have been addressed in various study designs, but the results do not exhibit any applied clinical benefit for CKD-patients. The "crusade" against cardiorenal morbidity and mortality in CKD-patients is in some instances, derailed. We propose a therapeutic paradigm advancing from isolated treatment targets, as practiced today, to precision medicine involving patient phenotypes with distinct underlying pathophysiology. In this regard we propose two steps, based on current stratification management of corona virus disease-19 and sepsis. First, select patients who are expected to have a high mortality, i.e., a prognostic enrichment. Second, select patients who are likely to respond to a specific therapy, i.e., a predictive enrichment.

Clinical and Experimental Study of High Mobility Group Box-2 and Valvular Calcification in Elderly Patients with Degenerative Heart Valve Disease

Introduction: The aim of this study was to investigate the relationship between the high mobility group box-2 (HMGB2) and valve calcification in senile degenerative heart valve disease (SDHVD). Methods: According to the echocardiographic results, patients with calcified heart valves were used as the experimental group and patients without calcified heart valves were used as the control group; blood was drawn for testing, and serum levels of HMGB2 were measured by an enzyme-linked immunosorbent assay. Human heart valve interstitial cells (hVICs) cultured in vitro were randomly divided into two groups. The calcification group was cultured with a medium containing calcification induction solution and cells were induced on days 1, 3, and 5, and the control group was cultured with a standard medium. Expression of bone morphogenetic protein 4 (BMP-4) and HMGB2 in both groups was detected by Western blot. RT-PCR was performed to detect the expression of the HMGB2 gene during calcification. The hVICs were cultured in vitro for 4 days with different concentrations of exogenous HMGB2 (0.01 μg/mL, 0.1 μg/mL, 1 μg/mL, 2 μg/mL), while the control group was cultured with a standard medium and the expression of BMP-4 and NF-κB P65 was detected by Western blot. Results: The serum level of HMGB2 was 7.90 (5.92, 12.39) μg/L, higher than that of 7.06 (5.06, 9.73) μg/L in the valve calcification group in elderly patients with degenerative valve disease (p = 0.005); the differences were statistically significant. In in vitro experiments, the cellular calcification protein BMP-4 and the HMGB2 protein were higher in the calcification group compared to the control group (p < 0.05). Exogenous stimulation of hVICs with HMGB2 was able to upregulate the expression of BMP-4 and NF-κB P65 (p < 0.05). Conclusions: HMGB2 is correlated with valvular calcification in senile degenerative heart valve disease. The HMGB2 protein may promote the process of SDHVD valve calcification by activating the NF-κB pathway and upregulating the expression of BMP-4.

Abnormal mechanical stress on bicuspid aortic valve induces valvular calcification and inhibits Notch1/NICD/Runx2 signal.

Bicuspid aortic valve (BAV) is a congenital cardiac deformity, increasing the risk of developing calcific aortic valve disease (CAVD). The disturbance of hemodynamics can induce valvular calcification, but the mechanism has not been fully identified. We constructed a finite element model (FEM) of the aortic valve based on the computed tomography angiography (CTA) data from BAV patients and tricuspid aortic valve (TAV) individuals. We analyzed the hemodynamic properties based on our model and investigated the characteristics of mechanical stimuli on BAV. Further, we detected the expression of Notch, NICD and Runx2 in valve samples and identified the association between mechanical stress and the Notch1 signaling pathway. Finite element analysis showed that at diastole phase, the equivalent stress on the root of BAV was significantly higher than that on the TAV leaflet. Correspondingly, the expression of Notch1 and NICH decreased and the expression of Runx2 elevated significantly on large BAV leaflet belly, which is associated with equivalent stress on leaflet. Our findings indicated that the root of BAV suffered higher mechanical stress due to the abnormal hemodynamic environment, and the disturbance of the Notch1/NICD/Runx2 signaling pathway caused by mechanical stimuli contributed to valvular calcification.

Predictive role of cardiac valvular calcification in all-cause mortality of Chinese initial haemodialysis patients: a follow-up study of 4 years

BackgroundCardiac valvular calcification (CVC) is prevalent in haemodialysis (HD) patients. Its association with mortality in Chinese incident haemodialysis (IHD) patients remains unknown.MethodsA total of 224 IHD patients who had just begun HD therapy at Zhongshan Hospital, Fudan University, were enrolled and divided into two groups according to the detection of cardiac valvular calcification (CVC) by echocardiography. The patients were followed for a median of 4 years for all-cause mortality and cardiovascular mortality.ResultsDuring follow-up, 56 (25.0%) patients died, including 29 (51.8%) of cardiovascular disease. The adjusted HR related to all-cause mortality was 2.14 (95% CI, 1.05–4.39) for patients with cardiac valvular calcification. However, CVC was not an independent risk factor for cardiovascular mortality in patients who had just begun HD therapy.ConclusionCVC at baseline is an independent risk factor for all-cause mortality in HD patients and makes an independent contribution to the prediction of all-cause mortality. These findings support the use of echocardiography at the beginning of HD.

Rho A/ROCK1 signaling-mediated metabolic reprogramming of valvular interstitial cells toward Warburg effect accelerates aortic valve calcification via AMPK/RUNX2 axis

The aberrant differentiation of valvular interstitial cells (VICs) to osteogenic lineages promotes calcified aortic valves disease (CAVD), partly activated by potentially destructive hemodynamic forces. These involve Rho A/ROCK1 signaling, a mechano-sensing pathway. However, how Rho A/ROCK1 signaling transduces mechanical signals into cellular responses and disrupts normal VIC homeostasis remain unclear. We examined Rho A/ROCK1 signaling in human aortic valves, and further detected how Rho A/ROCK1 signaling regulates mineralization in human VICs. Aortic valves (CAVD n = 22, normal control (NC) n = 12) from patients undergoing valve replacement were investigated. Immunostaining and western blotting analysis indicated that Rho A/ROCK1 signaling, as well as key transporters and enzymes involved in the Warburg effect, were markedly upregulated in human calcified aortic valves compared with those in the controls. In vitro, Rho A/ROCK1-induced calcification was confirmed as AMPK-dependent, via a mechanism involving metabolic reprogramming of human VICs to Warburg effect. Y-27632, a selective ROCK1 inhibitor, suppressed the Warburg effect, rescued AMPK activity and subsequently increased RUNX2 ubiquitin-proteasome degradation, leading to decreased RUNX2 protein accumulation in human VICs under pathological osteogenic stimulus. Rho A/ROCK1 signaling, which is elevated in human calcified aortic valves, plays a positive role in valvular calcification, partially through its ability to drive metabolic switching of VICs to the Warburg effect, leading to altered AMPK activity and RUNX2 protein accumulation. Thus, Rho A/ROCK1 signaling could be an important and unrecognized hub of destructive hemodynamics and cellular aerobic glycolysis that is essential to promote the CAVD process.

Network-Guided Multiomic Mapping of Aortic Valve Calcification.

Despite devastating clinical sequelae of calcific aortic valve disease that range from left ventricular remodeling to arrhythmias, heart failure, and early death, the molecular insights into disease initiation and progression are limited and pharmacotherapies remain unavailable. The pathobiology of calcific aortic valve disease is complex and comprehensive studies are challenging valvular calcification is heterogeneous and occurs preferentially on the aortic surface, along a fibrocalcific spectrum. Here, we review efforts to study (epi-)genomic, transcriptomic, proteomic, and metabolomic aspects of aortic valve calcification in combination with network medicine-/systems biology-based strategies to integrate multilayered omics datasets and prioritize druggable targets for experimental validation studies. Ultimately, such holistic approach efforts may open therapeutic avenues that go beyond invasive and costly valve replacement therapy.

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.

Sortilin enhances fibrosis and calcification in aortic valve disease by inducing interstitial cell heterogeneity.

Calcific aortic valve disease (CAVD) is the most common valve disease, which consists of a chronic interplay of inflammation, fibrosis, and calcification. In this study, sortilin (SORT1) was identified as a novel key player in the pathophysiology of CAVD, and its role in the transformation of valvular interstitial cells (VICs) into pathological phenotypes is explored. An aortic valve (AV) wire injury (AVWI) mouse model with sortilin deficiency was used to determine the effects of sortilin on AV stenosis, fibrosis, and calcification. In vitro experiments employed human primary VICs cultured in osteogenic conditions for 7, 14, and 21 days; and processed for imaging, proteomics, and transcriptomics including single-cell RNA-sequencing (scRNA-seq). The AVWI mouse model showed reduced AV fibrosis, calcification, and stenosis in sortilin-deficient mice vs. littermate controls. Protein studies identified the transition of human VICs into a myofibroblast-like phenotype mediated by sortilin. Sortilin loss-of-function decreased in vitro VIC calcification. ScRNA-seq identified 12 differentially expressed cell clusters in human VIC samples, where a novel combined inflammatory myofibroblastic-osteogenic VIC (IMO-VIC) phenotype was detected with increased expression of SORT1, COL1A1, WNT5A, IL-6, and serum amyloid A1. VICs sequenced with sortilin deficiency showed decreased IMO-VIC phenotype. Sortilin promotes CAVD by mediating valvular fibrosis and calcification, and a newly identified phenotype (IMO-VIC). This is the first study to examine the role of sortilin in valvular calcification and it may render it a therapeutic target to inhibit IMO-VIC emergence by simultaneously reducing inflammation, fibrosis, and calcification, the three key pathological processes underlying CAVD.

Myeloid CCN3 protects against aortic valve calcification

BackgroundCellular communication network factor 3 (CCN3) has been implicated in the regulation of osteoblast differentiation. However, it is not known if CCN3 can regulate valvular calcification. While macrophages have been shown to regulate valvular calcification, the molecular and cellular mechanisms of this process remain poorly understood. In the present study, we investigated the role of macrophage-derived CCN3 in the progression of calcific aortic valve disease.MethodsMyeloid-specific knockout of CCN3 (Mye-CCN3-KO) and control mice were subjected to a single tail intravenous injection of AAV encoding mutant mPCSK9 (rAAV8/D377Y-mPCSK9) to induce hyperlipidemia. AAV-injected mice were then fed a high fat diet for 40 weeks. At the conclusion of high fat diet feeding, tissues were harvested and subjected to histologic and pathologic analyses. In vitro, bone marrow-derived macrophages (BMDM) were obtained from Mye-CCN3-KO and control mice and the expression of bone morphogenic protein signaling related gene were verified via quantitative real-time PCR and Western blotting. The BMDM conditioned medium was cocultured with human valvular intersititial cells which was artificially induced calcification to test the effect of the conditioned medium via Western blotting and Alizarin red staining.ResultsEchocardiography revealed that both male and female Mye-CCN3-KO mice displayed compromised aortic valvular function accompanied by exacerbated valve thickness and cardiac dysfunction. Histologically, Alizarin-Red staining revealed a marked increase in aortic valve calcification in Mye-CCN3-KO mice when compared to the controls. In vitro, CCN3 deficiency augmented BMP2 production and secretion from bone marrow-derived macrophages. In addition, human valvular interstitial cells cultured with conditioned media from CCN3-deficient BMDMs resulted in exaggerated pro-calcifying gene expression and the consequent calcification.ConclusionOur data uncovered a novel role of myeloid CCN3 in the regulation of aortic valve calcification. Modulation of BMP2 production and secretion in macrophages might serve as a key mechanism for macrophage-derived CCN3’s anti-calcification function in the development of CAVD.9PRL6fCjY3KKJN46VmAQeQVideo

Assessment of Vascular and Valvular Calcification Improves Screening for Coronary Artery Disease Before Liver Transplantation

Coronary artery disease (CAD) is common in patients with cirrhosis who underwent orthotopic liver transplantation (OLT) evaluation and stress echocardiogram (echo) has a low sensitivity in these patients. This study aimed to assess the impact of vascular and valvular calcification on the ability to identify CAD before OLT. We performed a case-control study of 88 patients with and 97 without obstructive CAD who underwent OLT evaluation. All patients had a preoperative stress echo, abdominal computed tomography, and cardiac catheterization. A series of nested logistic regression models of CAD were fit by adding independent variables of vascular (including coronary) calcification, aortic and mitral valve calcification, age, gender, and history of diabetes mellitus requiring insulin to a baseline model of abnormal stress echo. Compared with stress echo alone, identification of the presence or absence of vascular and valvular calcification on routine preoperative computed tomography and echo improved the diagnostic performance for the detection of CAD based on coronary angiogram when combined with stress echo in patients with cirrhosis who underwent OLT evaluation (area under the curve 0.58 vs 0.73, p <0.001), which is even further improved when age, gender, and history of diabetes mellitus requiring insulin are considered (area under the curve 0.58 vs 0.80, p <0.001). Achieving target heart rate (p=0.92) or rate-pressure product >25,000 (p=0.63) did not improve the ability of stress echo to identify CAD. In conclusion, the use of abdominal vascular, coronary artery, and valvular calcification, along with stress echo, improves the ability to identify and rule out obstructive CAD before OLT compared with stress echo alone.

Diagnostic Performance of Cardiac CT and Transthoracic Echocardiography for Detection of Surgically Confirmed Bicuspid Aortic Valve: Effect of Calcium Extent and Valve Subtypes.

This study aimed to compare the diagnostic performance of cardiac CT and transthoracic echocardiogram (TTE) depending on the degree of valvular calcification and bicuspid aortic valve (BAV) subtype. This retrospective study included 266 consecutive patients (106 with BAV and 160 with tricuspid aortic valve) who underwent cardiac CT and TTE before aortic valve replacement. Cardiac CT was used to evaluate the morphology of the aortic valve, and a calcium scoring scan was used to quantify valve calcium. The aortic valves were classified into fused and two-sinus types. The diagnostic accuracy of cardiac CT and TTE was calculated using a reference standard for intraoperative inspection. CT demonstrated significantly higher sensitivity, negative predictive value, and accuracy than TTE in detecting BAV (p < 0.001, p < 0.001, and p = 0.003, respectively). The TTE sensitivity tended to decrease as valvular calcification increased. The error rate of TTE for CT was 10.9% for the two-sinus type of BAV and 28.3% for the fused type (p = 0.044). Cardiac CT had a higher diagnostic performance in detecting BAV than TTE and may help diagnose BAV, particularly in patients with severe valvular calcification.

Inactive Matrix Gla Protein in Relation to Renal and Cardiac Functions and Cardiac Valvular Calcification Among Type 2 Diabetes Patients.

Matrix Gla protein (MGP) is a robust innate suppressor of the detrimental process of vascular calcification in the human body. The interrelationship between circulating MGP levels and renal and cardiac dysfunction, besides echocardiographic calcification score (ECS) was investigated in a sample of type 2 diabetes (T2D) patients. The study included 130 subjects. They were 95 patients with T2D and 35 age- and sex-matched healthy controls. Patients were further subdivided into 52 T2D patients without DKD (eGFR ⩾ 60 ml/minute/1.73 m²) and 43 T2D persons with DKD (eGFR > 60 ml/minute/1.73 m²). Serum MGP levels, determined by ELISA, renal function tests, lipid profile, and echocardiography were studied in all participants. Significantly elevated circulating inactive MGP level was noted in individuals having T2D compared to controls. It correlated negatively with eGFR and left ventricular (LV) diastolic and systolic functions and positively with indices of LV hypertrophy. ECS was significantly increased in both T2D groups compared to controls and in DKD group compared to the diabetic group without DKD. A significant positive correlation was observed between inactive MGP and ECS. Serum inactive MGP may contribute to the development of DKD and to the associated process of cardiac valvular calcification. It may be a beneficial diagnostic marker for early prediction of cardiac calcification and preclinical LV systolic and diastolic dysfunction in T2D patients, especially in those complicated with DKD.

Prognosis of Heart Valve Calcification on Cardiovascular Events in Hemodialysis Patients without Central Venous Catheters

Introduction: Heart valvular calcification (HVC) is an important predictor of cardiovascular events (CEs) and all-cause mortality in dialysis patients. Patients in the early stage of dialysis or those with central venous catheters (CVC) are also at high risk of cardiovascular and all-cause mortality. It could be a confounding factor for the prognosis of HVC on CE. Methods: From March 2017 to April 2022, the prognosis of HVC on CE and all-cause mortality was studied retrospectively in 158 hemodialysis (HD) patients who used arteriovenous fistulas or arteriovenous grafts as vascular access and entered HD for more than 12 months. Results: Out of 158 patients, 70 (44.3%) were diagnosed with HVC via echocardiography. A total of 180 CEs occurred during follow-up. Among them, acute heart failure accounted for 62.66%, and its prevalence was significantly higher in the HVC group than that in the non-HVC group (p < 0.0001). The cumulative incidence of CE-free survival in the HVC group was significantly lower than that in the non-HVC group (p = 0.030). Only 11 patients died, and there was no significant difference in all-cause mortality between the two groups (p = 0.560). Multivariate COX regression analyses showed that HD vintage, mitral valve calcification, and aortic valve regurgitation (AR)/aortic valve stenosis (AS) but not aortic valve calcification were risk factors for CE (p < 0.05). Conclusion: After excluding the factors of the early stage of HD and CVC, HVC remained a predictor of adverse CE in HD patients.